1 // SPDX-License-Identifier: GPL-2.0-only
2 /* binder.c
3 *
4 * Android IPC Subsystem
5 *
6 * Copyright (C) 2007-2008 Google, Inc.
7 */
8
9 /*
10 * Locking overview
11 *
12 * There are 3 main spinlocks which must be acquired in the
13 * order shown:
14 *
15 * 1) proc->outer_lock : protects binder_ref
16 * binder_proc_lock() and binder_proc_unlock() are
17 * used to acq/rel.
18 * 2) node->lock : protects most fields of binder_node.
19 * binder_node_lock() and binder_node_unlock() are
20 * used to acq/rel
21 * 3) proc->inner_lock : protects the thread and node lists
22 * (proc->threads, proc->waiting_threads, proc->nodes)
23 * and all todo lists associated with the binder_proc
24 * (proc->todo, thread->todo, proc->delivered_death and
25 * node->async_todo), as well as thread->transaction_stack
26 * binder_inner_proc_lock() and binder_inner_proc_unlock()
27 * are used to acq/rel
28 *
29 * Any lock under procA must never be nested under any lock at the same
30 * level or below on procB.
31 *
32 * Functions that require a lock held on entry indicate which lock
33 * in the suffix of the function name:
34 *
35 * foo_olocked() : requires node->outer_lock
36 * foo_nlocked() : requires node->lock
37 * foo_ilocked() : requires proc->inner_lock
38 * foo_oilocked(): requires proc->outer_lock and proc->inner_lock
39 * foo_nilocked(): requires node->lock and proc->inner_lock
40 * ...
41 */
42
43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44
45 #include <linux/fdtable.h>
46 #include <linux/file.h>
47 #include <linux/freezer.h>
48 #include <linux/fs.h>
49 #include <linux/list.h>
50 #include <linux/miscdevice.h>
51 #include <linux/module.h>
52 #include <linux/mutex.h>
53 #include <linux/nsproxy.h>
54 #include <linux/poll.h>
55 #include <linux/debugfs.h>
56 #include <linux/rbtree.h>
57 #include <linux/sched/signal.h>
58 #include <linux/sched/mm.h>
59 #include <linux/seq_file.h>
60 #include <linux/string.h>
61 #include <linux/uaccess.h>
62 #include <linux/pid_namespace.h>
63 #include <linux/security.h>
64 #include <linux/spinlock.h>
65 #include <linux/ratelimit.h>
66 #include <linux/syscalls.h>
67 #include <linux/task_work.h>
68 #include <linux/sizes.h>
69 #include <linux/ktime.h>
70
71 #include <uapi/linux/sched/types.h>
72 #include <uapi/linux/android/binder.h>
73
74 #include <linux/cacheflush.h>
75
76 #include "binder_netlink.h"
77 ANDROID_KABI_DECLONLY(net);
78
79 #include "binder_internal.h"
80 #include "binder_trace.h"
81 #include <trace/hooks/binder.h>
82
83 static HLIST_HEAD(binder_deferred_list);
84 static DEFINE_MUTEX(binder_deferred_lock);
85
86 static HLIST_HEAD(binder_devices);
87 static HLIST_HEAD(binder_procs);
88 static DEFINE_MUTEX(binder_procs_lock);
89
90 static HLIST_HEAD(binder_dead_nodes);
91 static DEFINE_SPINLOCK(binder_dead_nodes_lock);
92
93 static struct dentry *binder_debugfs_dir_entry_root;
94 static struct dentry *binder_debugfs_dir_entry_proc;
95 static atomic_t binder_last_id;
96
97 static int proc_show(struct seq_file *m, void *unused);
98 DEFINE_SHOW_ATTRIBUTE(proc);
99
100 #define FORBIDDEN_MMAP_FLAGS (VM_WRITE)
101
102 enum {
103 BINDER_DEBUG_USER_ERROR = 1U << 0,
104 BINDER_DEBUG_FAILED_TRANSACTION = 1U << 1,
105 BINDER_DEBUG_DEAD_TRANSACTION = 1U << 2,
106 BINDER_DEBUG_OPEN_CLOSE = 1U << 3,
107 BINDER_DEBUG_DEAD_BINDER = 1U << 4,
108 BINDER_DEBUG_DEATH_NOTIFICATION = 1U << 5,
109 BINDER_DEBUG_READ_WRITE = 1U << 6,
110 BINDER_DEBUG_USER_REFS = 1U << 7,
111 BINDER_DEBUG_THREADS = 1U << 8,
112 BINDER_DEBUG_TRANSACTION = 1U << 9,
113 BINDER_DEBUG_TRANSACTION_COMPLETE = 1U << 10,
114 BINDER_DEBUG_FREE_BUFFER = 1U << 11,
115 BINDER_DEBUG_INTERNAL_REFS = 1U << 12,
116 BINDER_DEBUG_PRIORITY_CAP = 1U << 13,
117 BINDER_DEBUG_SPINLOCKS = 1U << 14,
118 };
119 static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
120 BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
121 module_param_named(debug_mask, binder_debug_mask, uint, 0644);
122
123 char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
124 module_param_named(devices, binder_devices_param, charp, 0444);
125
126 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
127 static int binder_stop_on_user_error;
128
binder_set_stop_on_user_error(const char * val,const struct kernel_param * kp)129 static int binder_set_stop_on_user_error(const char *val,
130 const struct kernel_param *kp)
131 {
132 int ret;
133
134 ret = param_set_int(val, kp);
135 if (binder_stop_on_user_error < 2)
136 wake_up(&binder_user_error_wait);
137 return ret;
138 }
139 module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
140 param_get_int, &binder_stop_on_user_error, 0644);
141
binder_debug(int mask,const char * format,...)142 static __printf(2, 3) void binder_debug(int mask, const char *format, ...)
143 {
144 struct va_format vaf;
145 va_list args;
146
147 if (binder_debug_mask & mask) {
148 va_start(args, format);
149 vaf.va = &args;
150 vaf.fmt = format;
151 pr_info_ratelimited("%pV", &vaf);
152 va_end(args);
153 }
154 }
155
156 #define binder_txn_error(x...) \
157 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, x)
158
binder_user_error(const char * format,...)159 static __printf(1, 2) void binder_user_error(const char *format, ...)
160 {
161 struct va_format vaf;
162 va_list args;
163
164 if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) {
165 va_start(args, format);
166 vaf.va = &args;
167 vaf.fmt = format;
168 pr_info_ratelimited("%pV", &vaf);
169 va_end(args);
170 }
171
172 if (binder_stop_on_user_error)
173 binder_stop_on_user_error = 2;
174 }
175
176 #define binder_set_extended_error(ee, _id, _command, _param) \
177 do { \
178 (ee)->id = _id; \
179 (ee)->command = _command; \
180 (ee)->param = _param; \
181 } while (0)
182
183 #define to_flat_binder_object(hdr) \
184 container_of(hdr, struct flat_binder_object, hdr)
185
186 #define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr)
187
188 #define to_binder_buffer_object(hdr) \
189 container_of(hdr, struct binder_buffer_object, hdr)
190
191 #define to_binder_fd_array_object(hdr) \
192 container_of(hdr, struct binder_fd_array_object, hdr)
193
194 static struct binder_stats binder_stats;
195
binder_stats_deleted(enum binder_stat_types type)196 static inline void binder_stats_deleted(enum binder_stat_types type)
197 {
198 atomic_inc(&binder_stats.obj_deleted[type]);
199 }
200
binder_stats_created(enum binder_stat_types type)201 static inline void binder_stats_created(enum binder_stat_types type)
202 {
203 atomic_inc(&binder_stats.obj_created[type]);
204 }
205
206 struct binder_transaction_log_entry {
207 int debug_id;
208 int debug_id_done;
209 int call_type;
210 int from_proc;
211 int from_thread;
212 int target_handle;
213 int to_proc;
214 int to_thread;
215 int to_node;
216 int data_size;
217 int offsets_size;
218 int return_error_line;
219 uint32_t return_error;
220 uint32_t return_error_param;
221 char context_name[BINDERFS_MAX_NAME + 1];
222 };
223
224 struct binder_transaction_log {
225 atomic_t cur;
226 bool full;
227 struct binder_transaction_log_entry entry[32];
228 };
229
230 static struct binder_transaction_log binder_transaction_log;
231 static struct binder_transaction_log binder_transaction_log_failed;
232
binder_transaction_log_add(struct binder_transaction_log * log)233 static struct binder_transaction_log_entry *binder_transaction_log_add(
234 struct binder_transaction_log *log)
235 {
236 struct binder_transaction_log_entry *e;
237 unsigned int cur = atomic_inc_return(&log->cur);
238
239 if (cur >= ARRAY_SIZE(log->entry))
240 log->full = true;
241 e = &log->entry[cur % ARRAY_SIZE(log->entry)];
242 WRITE_ONCE(e->debug_id_done, 0);
243 /*
244 * write-barrier to synchronize access to e->debug_id_done.
245 * We make sure the initialized 0 value is seen before
246 * memset() other fields are zeroed by memset.
247 */
248 smp_wmb();
249 memset(e, 0, sizeof(*e));
250 return e;
251 }
252
253 enum binder_deferred_state {
254 BINDER_DEFERRED_FLUSH = 0x01,
255 BINDER_DEFERRED_RELEASE = 0x02,
256 };
257
258 enum {
259 BINDER_LOOPER_STATE_REGISTERED = 0x01,
260 BINDER_LOOPER_STATE_ENTERED = 0x02,
261 BINDER_LOOPER_STATE_EXITED = 0x04,
262 BINDER_LOOPER_STATE_INVALID = 0x08,
263 BINDER_LOOPER_STATE_WAITING = 0x10,
264 BINDER_LOOPER_STATE_POLL = 0x20,
265 };
266
267 /**
268 * binder_proc_lock() - Acquire outer lock for given binder_proc
269 * @proc: struct binder_proc to acquire
270 *
271 * Acquires proc->outer_lock. Used to protect binder_ref
272 * structures associated with the given proc.
273 */
274 #define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__)
275 static void
_binder_proc_lock(struct binder_proc * proc,int line)276 _binder_proc_lock(struct binder_proc *proc, int line)
277 __acquires(&proc->outer_lock)
278 {
279 binder_debug(BINDER_DEBUG_SPINLOCKS,
280 "%s: line=%d\n", __func__, line);
281 spin_lock(&proc->outer_lock);
282 }
283
284 /**
285 * binder_proc_unlock() - Release outer lock for given binder_proc
286 * @proc: struct binder_proc to acquire
287 *
288 * Release lock acquired via binder_proc_lock()
289 */
290 #define binder_proc_unlock(proc) _binder_proc_unlock(proc, __LINE__)
291 static void
_binder_proc_unlock(struct binder_proc * proc,int line)292 _binder_proc_unlock(struct binder_proc *proc, int line)
293 __releases(&proc->outer_lock)
294 {
295 binder_debug(BINDER_DEBUG_SPINLOCKS,
296 "%s: line=%d\n", __func__, line);
297 spin_unlock(&proc->outer_lock);
298 }
299
300 /**
301 * binder_inner_proc_lock() - Acquire inner lock for given binder_proc
302 * @proc: struct binder_proc to acquire
303 *
304 * Acquires proc->inner_lock. Used to protect todo lists
305 */
306 #define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__)
307 static void
_binder_inner_proc_lock(struct binder_proc * proc,int line)308 _binder_inner_proc_lock(struct binder_proc *proc, int line)
309 __acquires(&proc->inner_lock)
310 {
311 binder_debug(BINDER_DEBUG_SPINLOCKS,
312 "%s: line=%d\n", __func__, line);
313 spin_lock(&proc->inner_lock);
314 }
315
316 /**
317 * binder_inner_proc_unlock() - Release inner lock for given binder_proc
318 * @proc: struct binder_proc to acquire
319 *
320 * Release lock acquired via binder_inner_proc_lock()
321 */
322 #define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__)
323 static void
_binder_inner_proc_unlock(struct binder_proc * proc,int line)324 _binder_inner_proc_unlock(struct binder_proc *proc, int line)
325 __releases(&proc->inner_lock)
326 {
327 binder_debug(BINDER_DEBUG_SPINLOCKS,
328 "%s: line=%d\n", __func__, line);
329 spin_unlock(&proc->inner_lock);
330 }
331
332 /**
333 * binder_node_lock() - Acquire spinlock for given binder_node
334 * @node: struct binder_node to acquire
335 *
336 * Acquires node->lock. Used to protect binder_node fields
337 */
338 #define binder_node_lock(node) _binder_node_lock(node, __LINE__)
339 static void
_binder_node_lock(struct binder_node * node,int line)340 _binder_node_lock(struct binder_node *node, int line)
341 __acquires(&node->lock)
342 {
343 binder_debug(BINDER_DEBUG_SPINLOCKS,
344 "%s: line=%d\n", __func__, line);
345 spin_lock(&node->lock);
346 }
347
348 /**
349 * binder_node_unlock() - Release spinlock for given binder_proc
350 * @node: struct binder_node to acquire
351 *
352 * Release lock acquired via binder_node_lock()
353 */
354 #define binder_node_unlock(node) _binder_node_unlock(node, __LINE__)
355 static void
_binder_node_unlock(struct binder_node * node,int line)356 _binder_node_unlock(struct binder_node *node, int line)
357 __releases(&node->lock)
358 {
359 binder_debug(BINDER_DEBUG_SPINLOCKS,
360 "%s: line=%d\n", __func__, line);
361 spin_unlock(&node->lock);
362 }
363
364 /**
365 * binder_node_inner_lock() - Acquire node and inner locks
366 * @node: struct binder_node to acquire
367 *
368 * Acquires node->lock. If node->proc also acquires
369 * proc->inner_lock. Used to protect binder_node fields
370 */
371 #define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__)
372 static void
_binder_node_inner_lock(struct binder_node * node,int line)373 _binder_node_inner_lock(struct binder_node *node, int line)
374 __acquires(&node->lock) __acquires(&node->proc->inner_lock)
375 {
376 binder_debug(BINDER_DEBUG_SPINLOCKS,
377 "%s: line=%d\n", __func__, line);
378 spin_lock(&node->lock);
379 if (node->proc)
380 binder_inner_proc_lock(node->proc);
381 else
382 /* annotation for sparse */
383 __acquire(&node->proc->inner_lock);
384 }
385
386 /**
387 * binder_node_inner_unlock() - Release node and inner locks
388 * @node: struct binder_node to acquire
389 *
390 * Release lock acquired via binder_node_lock()
391 */
392 #define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__)
393 static void
_binder_node_inner_unlock(struct binder_node * node,int line)394 _binder_node_inner_unlock(struct binder_node *node, int line)
395 __releases(&node->lock) __releases(&node->proc->inner_lock)
396 {
397 struct binder_proc *proc = node->proc;
398
399 binder_debug(BINDER_DEBUG_SPINLOCKS,
400 "%s: line=%d\n", __func__, line);
401 if (proc)
402 binder_inner_proc_unlock(proc);
403 else
404 /* annotation for sparse */
405 __release(&node->proc->inner_lock);
406 spin_unlock(&node->lock);
407 }
408
binder_worklist_empty_ilocked(struct list_head * list)409 static bool binder_worklist_empty_ilocked(struct list_head *list)
410 {
411 return list_empty(list);
412 }
413
414 /**
415 * binder_worklist_empty() - Check if no items on the work list
416 * @proc: binder_proc associated with list
417 * @list: list to check
418 *
419 * Return: true if there are no items on list, else false
420 */
binder_worklist_empty(struct binder_proc * proc,struct list_head * list)421 static bool binder_worklist_empty(struct binder_proc *proc,
422 struct list_head *list)
423 {
424 bool ret;
425
426 binder_inner_proc_lock(proc);
427 ret = binder_worklist_empty_ilocked(list);
428 binder_inner_proc_unlock(proc);
429 return ret;
430 }
431
432 /**
433 * binder_enqueue_work_ilocked() - Add an item to the work list
434 * @work: struct binder_work to add to list
435 * @target_list: list to add work to
436 *
437 * Adds the work to the specified list. Asserts that work
438 * is not already on a list.
439 *
440 * Requires the proc->inner_lock to be held.
441 */
442 static void
binder_enqueue_work_ilocked(struct binder_work * work,struct list_head * target_list)443 binder_enqueue_work_ilocked(struct binder_work *work,
444 struct list_head *target_list)
445 {
446 BUG_ON(target_list == NULL);
447 BUG_ON(work->entry.next && !list_empty(&work->entry));
448 trace_android_vh_binder_list_add_work(work, target_list);
449 list_add_tail(&work->entry, target_list);
450 }
451
452 /**
453 * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work
454 * @thread: thread to queue work to
455 * @work: struct binder_work to add to list
456 *
457 * Adds the work to the todo list of the thread. Doesn't set the process_todo
458 * flag, which means that (if it wasn't already set) the thread will go to
459 * sleep without handling this work when it calls read.
460 *
461 * Requires the proc->inner_lock to be held.
462 */
463 static void
binder_enqueue_deferred_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)464 binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread,
465 struct binder_work *work)
466 {
467 WARN_ON(!list_empty(&thread->waiting_thread_node));
468 binder_enqueue_work_ilocked(work, &thread->todo);
469 }
470
471 /**
472 * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list
473 * @thread: thread to queue work to
474 * @work: struct binder_work to add to list
475 *
476 * Adds the work to the todo list of the thread, and enables processing
477 * of the todo queue.
478 *
479 * Requires the proc->inner_lock to be held.
480 */
481 static void
binder_enqueue_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)482 binder_enqueue_thread_work_ilocked(struct binder_thread *thread,
483 struct binder_work *work)
484 {
485 WARN_ON(!list_empty(&thread->waiting_thread_node));
486 binder_enqueue_work_ilocked(work, &thread->todo);
487
488 /* (e)poll-based threads require an explicit wakeup signal when
489 * queuing their own work; they rely on these events to consume
490 * messages without I/O block. Without it, threads risk waiting
491 * indefinitely without handling the work.
492 */
493 if (thread->looper & BINDER_LOOPER_STATE_POLL &&
494 thread->pid == current->pid && !thread->process_todo)
495 wake_up_interruptible_sync(&thread->wait);
496
497 thread->process_todo = true;
498 }
499
500 /**
501 * binder_enqueue_thread_work() - Add an item to the thread work list
502 * @thread: thread to queue work to
503 * @work: struct binder_work to add to list
504 *
505 * Adds the work to the todo list of the thread, and enables processing
506 * of the todo queue.
507 */
508 static void
binder_enqueue_thread_work(struct binder_thread * thread,struct binder_work * work)509 binder_enqueue_thread_work(struct binder_thread *thread,
510 struct binder_work *work)
511 {
512 binder_inner_proc_lock(thread->proc);
513 binder_enqueue_thread_work_ilocked(thread, work);
514 binder_inner_proc_unlock(thread->proc);
515 }
516
517 static void
binder_dequeue_work_ilocked(struct binder_work * work)518 binder_dequeue_work_ilocked(struct binder_work *work)
519 {
520 list_del_init(&work->entry);
521 }
522
523 /**
524 * binder_dequeue_work() - Removes an item from the work list
525 * @proc: binder_proc associated with list
526 * @work: struct binder_work to remove from list
527 *
528 * Removes the specified work item from whatever list it is on.
529 * Can safely be called if work is not on any list.
530 */
531 static void
binder_dequeue_work(struct binder_proc * proc,struct binder_work * work)532 binder_dequeue_work(struct binder_proc *proc, struct binder_work *work)
533 {
534 binder_inner_proc_lock(proc);
535 binder_dequeue_work_ilocked(work);
536 binder_inner_proc_unlock(proc);
537 }
538
binder_dequeue_work_head_ilocked(struct list_head * list)539 static struct binder_work *binder_dequeue_work_head_ilocked(
540 struct list_head *list)
541 {
542 struct binder_work *w;
543
544 w = list_first_entry_or_null(list, struct binder_work, entry);
545 if (w)
546 list_del_init(&w->entry);
547 return w;
548 }
549
550 static void
551 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
552 static void binder_free_thread(struct binder_thread *thread);
553 static void binder_free_proc(struct binder_proc *proc);
554 static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
555
binder_has_work_ilocked(struct binder_thread * thread,bool do_proc_work)556 static bool binder_has_work_ilocked(struct binder_thread *thread,
557 bool do_proc_work)
558 {
559 bool has_work = thread->process_todo ||
560 thread->looper_need_return ||
561 (do_proc_work &&
562 !binder_worklist_empty_ilocked(&thread->proc->todo));
563 trace_android_vh_binder_has_special_work_ilocked(thread, do_proc_work, &has_work);
564 return has_work;
565 }
566
binder_has_work(struct binder_thread * thread,bool do_proc_work)567 static bool binder_has_work(struct binder_thread *thread, bool do_proc_work)
568 {
569 bool has_work;
570
571 binder_inner_proc_lock(thread->proc);
572 has_work = binder_has_work_ilocked(thread, do_proc_work);
573 binder_inner_proc_unlock(thread->proc);
574
575 return has_work;
576 }
577
binder_available_for_proc_work_ilocked(struct binder_thread * thread)578 static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread)
579 {
580 return !thread->transaction_stack &&
581 binder_worklist_empty_ilocked(&thread->todo);
582 }
583
binder_wakeup_poll_threads_ilocked(struct binder_proc * proc,bool sync)584 static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc,
585 bool sync)
586 {
587 struct rb_node *n;
588 struct binder_thread *thread;
589
590 for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
591 thread = rb_entry(n, struct binder_thread, rb_node);
592 if (thread->looper & BINDER_LOOPER_STATE_POLL &&
593 binder_available_for_proc_work_ilocked(thread)) {
594 if (sync)
595 wake_up_interruptible_sync(&thread->wait);
596 else
597 wake_up_interruptible(&thread->wait);
598 }
599 }
600 }
601
602 /**
603 * binder_select_thread_ilocked() - selects a thread for doing proc work.
604 * @proc: process to select a thread from
605 *
606 * Note that calling this function moves the thread off the waiting_threads
607 * list, so it can only be woken up by the caller of this function, or a
608 * signal. Therefore, callers *should* always wake up the thread this function
609 * returns.
610 *
611 * Return: If there's a thread currently waiting for process work,
612 * returns that thread. Otherwise returns NULL.
613 */
614 static struct binder_thread *
binder_select_thread_ilocked(struct binder_proc * proc)615 binder_select_thread_ilocked(struct binder_proc *proc)
616 {
617 struct binder_thread *thread;
618
619 assert_spin_locked(&proc->inner_lock);
620 thread = list_first_entry_or_null(&proc->waiting_threads,
621 struct binder_thread,
622 waiting_thread_node);
623
624 if (thread)
625 list_del_init(&thread->waiting_thread_node);
626
627 return thread;
628 }
629
630 /**
631 * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work.
632 * @proc: process to wake up a thread in
633 * @thread: specific thread to wake-up (may be NULL)
634 * @sync: whether to do a synchronous wake-up
635 *
636 * This function wakes up a thread in the @proc process.
637 * The caller may provide a specific thread to wake-up in
638 * the @thread parameter. If @thread is NULL, this function
639 * will wake up threads that have called poll().
640 *
641 * Note that for this function to work as expected, callers
642 * should first call binder_select_thread() to find a thread
643 * to handle the work (if they don't have a thread already),
644 * and pass the result into the @thread parameter.
645 */
binder_wakeup_thread_ilocked(struct binder_proc * proc,struct binder_thread * thread,bool sync)646 static void binder_wakeup_thread_ilocked(struct binder_proc *proc,
647 struct binder_thread *thread,
648 bool sync)
649 {
650 assert_spin_locked(&proc->inner_lock);
651
652 if (thread) {
653 if (sync)
654 wake_up_interruptible_sync(&thread->wait);
655 else
656 wake_up_interruptible(&thread->wait);
657 return;
658 }
659
660 /* Didn't find a thread waiting for proc work; this can happen
661 * in two scenarios:
662 * 1. All threads are busy handling transactions
663 * In that case, one of those threads should call back into
664 * the kernel driver soon and pick up this work.
665 * 2. Threads are using the (e)poll interface, in which case
666 * they may be blocked on the waitqueue without having been
667 * added to waiting_threads. For this case, we just iterate
668 * over all threads not handling transaction work, and
669 * wake them all up. We wake all because we don't know whether
670 * a thread that called into (e)poll is handling non-binder
671 * work currently.
672 */
673 binder_wakeup_poll_threads_ilocked(proc, sync);
674 }
675
binder_wakeup_proc_ilocked(struct binder_proc * proc)676 static void binder_wakeup_proc_ilocked(struct binder_proc *proc)
677 {
678 struct binder_thread *thread = binder_select_thread_ilocked(proc);
679
680 binder_wakeup_thread_ilocked(proc, thread, /* sync = */false);
681 }
682
is_rt_policy(int policy)683 static bool is_rt_policy(int policy)
684 {
685 return policy == SCHED_FIFO || policy == SCHED_RR;
686 }
687
is_fair_policy(int policy)688 static bool is_fair_policy(int policy)
689 {
690 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
691 }
692
binder_supported_policy(int policy)693 static bool binder_supported_policy(int policy)
694 {
695 return is_fair_policy(policy) || is_rt_policy(policy);
696 }
697
to_userspace_prio(int policy,int kernel_priority)698 static int to_userspace_prio(int policy, int kernel_priority)
699 {
700 if (is_fair_policy(policy))
701 return PRIO_TO_NICE(kernel_priority);
702 else
703 return MAX_RT_PRIO - 1 - kernel_priority;
704 }
705
to_kernel_prio(int policy,int user_priority)706 static int to_kernel_prio(int policy, int user_priority)
707 {
708 if (is_fair_policy(policy))
709 return NICE_TO_PRIO(user_priority);
710 else
711 return MAX_RT_PRIO - 1 - user_priority;
712 }
713
binder_do_set_priority(struct binder_thread * thread,const struct binder_priority * desired,bool verify)714 static void binder_do_set_priority(struct binder_thread *thread,
715 const struct binder_priority *desired,
716 bool verify)
717 {
718 struct task_struct *task = thread->task;
719 int priority; /* user-space prio value */
720 bool has_cap_nice;
721 unsigned int policy = desired->sched_policy;
722
723 if (task->policy == policy && task->normal_prio == desired->prio) {
724 spin_lock(&thread->prio_lock);
725 if (thread->prio_state == BINDER_PRIO_PENDING)
726 thread->prio_state = BINDER_PRIO_SET;
727 spin_unlock(&thread->prio_lock);
728 return;
729 }
730
731 has_cap_nice = has_capability_noaudit(task, CAP_SYS_NICE);
732
733 priority = to_userspace_prio(policy, desired->prio);
734
735 if (verify && is_rt_policy(policy) && !has_cap_nice) {
736 long max_rtprio = task_rlimit(task, RLIMIT_RTPRIO);
737
738 if (max_rtprio == 0) {
739 policy = SCHED_NORMAL;
740 priority = MIN_NICE;
741 } else if (priority > max_rtprio) {
742 priority = max_rtprio;
743 }
744 }
745
746 if (verify && is_fair_policy(policy) && !has_cap_nice) {
747 long min_nice = rlimit_to_nice(task_rlimit(task, RLIMIT_NICE));
748
749 if (min_nice > MAX_NICE) {
750 binder_user_error("%d RLIMIT_NICE not set\n",
751 task->pid);
752 return;
753 } else if (priority < min_nice) {
754 priority = min_nice;
755 }
756 }
757
758 if (policy != desired->sched_policy ||
759 to_kernel_prio(policy, priority) != desired->prio)
760 binder_debug(BINDER_DEBUG_PRIORITY_CAP,
761 "%d: priority %d not allowed, using %d instead\n",
762 task->pid, desired->prio,
763 to_kernel_prio(policy, priority));
764
765 trace_binder_set_priority(task->tgid, task->pid, task->normal_prio,
766 to_kernel_prio(policy, priority),
767 desired->prio);
768
769 spin_lock(&thread->prio_lock);
770 if (!verify && thread->prio_state == BINDER_PRIO_ABORT) {
771 /*
772 * A new priority has been set by an incoming nested
773 * transaction. Abort this priority restore and allow
774 * the transaction to run at the new desired priority.
775 */
776 spin_unlock(&thread->prio_lock);
777 binder_debug(BINDER_DEBUG_PRIORITY_CAP,
778 "%d: %s: aborting priority restore\n",
779 thread->pid, __func__);
780 return;
781 }
782
783 /* Set the actual priority */
784 if (task->policy != policy || is_rt_policy(policy)) {
785 struct sched_param params;
786
787 params.sched_priority = is_rt_policy(policy) ? priority : 0;
788
789 sched_setscheduler_nocheck(task,
790 policy | SCHED_RESET_ON_FORK,
791 ¶ms);
792 }
793 if (is_fair_policy(policy))
794 set_user_nice(task, priority);
795
796 thread->prio_state = BINDER_PRIO_SET;
797 spin_unlock(&thread->prio_lock);
798 }
799
binder_set_priority(struct binder_thread * thread,const struct binder_priority * desired)800 static void binder_set_priority(struct binder_thread *thread,
801 const struct binder_priority *desired)
802 {
803 binder_do_set_priority(thread, desired, /* verify = */ true);
804 }
805
binder_restore_priority(struct binder_thread * thread,const struct binder_priority * desired)806 static void binder_restore_priority(struct binder_thread *thread,
807 const struct binder_priority *desired)
808 {
809 binder_do_set_priority(thread, desired, /* verify = */ false);
810 }
811
binder_transaction_priority(struct binder_thread * thread,struct binder_transaction * t,struct binder_node * node)812 static void binder_transaction_priority(struct binder_thread *thread,
813 struct binder_transaction *t,
814 struct binder_node *node)
815 {
816 struct task_struct *task = thread->task;
817 struct binder_priority desired = t->priority;
818 const struct binder_priority node_prio = {
819 .sched_policy = node->sched_policy,
820 .prio = node->min_priority,
821 };
822
823 if (t->set_priority_called)
824 return;
825
826 t->set_priority_called = true;
827
828 if (!node->inherit_rt && is_rt_policy(desired.sched_policy)) {
829 desired.prio = NICE_TO_PRIO(0);
830 desired.sched_policy = SCHED_NORMAL;
831 }
832
833 if (node_prio.prio < desired.prio ||
834 (node_prio.prio == desired.prio &&
835 node_prio.sched_policy == SCHED_FIFO)) {
836 /*
837 * In case the minimum priority on the node is
838 * higher (lower value), use that priority. If
839 * the priority is the same, but the node uses
840 * SCHED_FIFO, prefer SCHED_FIFO, since it can
841 * run unbounded, unlike SCHED_RR.
842 */
843 desired = node_prio;
844 }
845
846 spin_lock(&thread->prio_lock);
847 if (thread->prio_state == BINDER_PRIO_PENDING) {
848 /*
849 * Task is in the process of changing priorities
850 * saving its current values would be incorrect.
851 * Instead, save the pending priority and signal
852 * the task to abort the priority restore.
853 */
854 t->saved_priority = thread->prio_next;
855 thread->prio_state = BINDER_PRIO_ABORT;
856 binder_debug(BINDER_DEBUG_PRIORITY_CAP,
857 "%d: saved pending priority %d\n",
858 current->pid, thread->prio_next.prio);
859 } else {
860 t->saved_priority.sched_policy = task->policy;
861 t->saved_priority.prio = task->normal_prio;
862 }
863 spin_unlock(&thread->prio_lock);
864
865 binder_set_priority(thread, &desired);
866 trace_android_vh_binder_set_priority(t, task);
867 }
868
binder_get_node_ilocked(struct binder_proc * proc,binder_uintptr_t ptr)869 static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc,
870 binder_uintptr_t ptr)
871 {
872 struct rb_node *n = proc->nodes.rb_node;
873 struct binder_node *node;
874
875 assert_spin_locked(&proc->inner_lock);
876
877 while (n) {
878 node = rb_entry(n, struct binder_node, rb_node);
879
880 if (ptr < node->ptr)
881 n = n->rb_left;
882 else if (ptr > node->ptr)
883 n = n->rb_right;
884 else {
885 /*
886 * take an implicit weak reference
887 * to ensure node stays alive until
888 * call to binder_put_node()
889 */
890 binder_inc_node_tmpref_ilocked(node);
891 return node;
892 }
893 }
894 return NULL;
895 }
896
binder_get_node(struct binder_proc * proc,binder_uintptr_t ptr)897 static struct binder_node *binder_get_node(struct binder_proc *proc,
898 binder_uintptr_t ptr)
899 {
900 struct binder_node *node;
901
902 binder_inner_proc_lock(proc);
903 node = binder_get_node_ilocked(proc, ptr);
904 binder_inner_proc_unlock(proc);
905 return node;
906 }
907
binder_init_node_ilocked(struct binder_proc * proc,struct binder_node * new_node,struct flat_binder_object * fp)908 static struct binder_node *binder_init_node_ilocked(
909 struct binder_proc *proc,
910 struct binder_node *new_node,
911 struct flat_binder_object *fp)
912 {
913 struct rb_node **p = &proc->nodes.rb_node;
914 struct rb_node *parent = NULL;
915 struct binder_node *node;
916 binder_uintptr_t ptr = fp ? fp->binder : 0;
917 binder_uintptr_t cookie = fp ? fp->cookie : 0;
918 __u32 flags = fp ? fp->flags : 0;
919 s8 priority;
920
921 assert_spin_locked(&proc->inner_lock);
922
923 while (*p) {
924
925 parent = *p;
926 node = rb_entry(parent, struct binder_node, rb_node);
927
928 if (ptr < node->ptr)
929 p = &(*p)->rb_left;
930 else if (ptr > node->ptr)
931 p = &(*p)->rb_right;
932 else {
933 /*
934 * A matching node is already in
935 * the rb tree. Abandon the init
936 * and return it.
937 */
938 binder_inc_node_tmpref_ilocked(node);
939 return node;
940 }
941 }
942 node = new_node;
943 binder_stats_created(BINDER_STAT_NODE);
944 node->tmp_refs++;
945 rb_link_node(&node->rb_node, parent, p);
946 rb_insert_color(&node->rb_node, &proc->nodes);
947 node->debug_id = atomic_inc_return(&binder_last_id);
948 node->proc = proc;
949 node->ptr = ptr;
950 node->cookie = cookie;
951 node->work.type = BINDER_WORK_NODE;
952 priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK;
953 node->sched_policy = (flags & FLAT_BINDER_FLAG_SCHED_POLICY_MASK) >>
954 FLAT_BINDER_FLAG_SCHED_POLICY_SHIFT;
955 node->min_priority = to_kernel_prio(node->sched_policy, priority);
956 node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS);
957 node->inherit_rt = !!(flags & FLAT_BINDER_FLAG_INHERIT_RT);
958 node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX);
959 spin_lock_init(&node->lock);
960 INIT_LIST_HEAD(&node->work.entry);
961 INIT_LIST_HEAD(&node->async_todo);
962 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
963 "%d:%d node %d u%016llx c%016llx created\n",
964 proc->pid, current->pid, node->debug_id,
965 (u64)node->ptr, (u64)node->cookie);
966
967 return node;
968 }
969
binder_new_node(struct binder_proc * proc,struct flat_binder_object * fp)970 static struct binder_node *binder_new_node(struct binder_proc *proc,
971 struct flat_binder_object *fp)
972 {
973 struct binder_node *node;
974 struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL);
975
976 if (!new_node)
977 return NULL;
978 binder_inner_proc_lock(proc);
979 node = binder_init_node_ilocked(proc, new_node, fp);
980 binder_inner_proc_unlock(proc);
981 if (node != new_node)
982 /*
983 * The node was already added by another thread
984 */
985 kfree(new_node);
986
987 return node;
988 }
989
binder_free_node(struct binder_node * node)990 static void binder_free_node(struct binder_node *node)
991 {
992 kfree(node);
993 binder_stats_deleted(BINDER_STAT_NODE);
994 }
995
binder_inc_node_nilocked(struct binder_node * node,int strong,int internal,struct list_head * target_list)996 static int binder_inc_node_nilocked(struct binder_node *node, int strong,
997 int internal,
998 struct list_head *target_list)
999 {
1000 struct binder_proc *proc = node->proc;
1001
1002 assert_spin_locked(&node->lock);
1003 if (proc)
1004 assert_spin_locked(&proc->inner_lock);
1005 if (strong) {
1006 if (internal) {
1007 if (target_list == NULL &&
1008 node->internal_strong_refs == 0 &&
1009 !(node->proc &&
1010 node == node->proc->context->binder_context_mgr_node &&
1011 node->has_strong_ref)) {
1012 pr_err("invalid inc strong node for %d\n",
1013 node->debug_id);
1014 return -EINVAL;
1015 }
1016 node->internal_strong_refs++;
1017 } else
1018 node->local_strong_refs++;
1019 if (!node->has_strong_ref && target_list) {
1020 struct binder_thread *thread = container_of(target_list,
1021 struct binder_thread, todo);
1022 binder_dequeue_work_ilocked(&node->work);
1023 BUG_ON(&thread->todo != target_list);
1024 binder_enqueue_deferred_thread_work_ilocked(thread,
1025 &node->work);
1026 }
1027 } else {
1028 if (!internal)
1029 node->local_weak_refs++;
1030 if (!node->has_weak_ref && list_empty(&node->work.entry)) {
1031 if (target_list == NULL) {
1032 pr_err("invalid inc weak node for %d\n",
1033 node->debug_id);
1034 return -EINVAL;
1035 }
1036 /*
1037 * See comment above
1038 */
1039 binder_enqueue_work_ilocked(&node->work, target_list);
1040 }
1041 }
1042 return 0;
1043 }
1044
binder_inc_node(struct binder_node * node,int strong,int internal,struct list_head * target_list)1045 static int binder_inc_node(struct binder_node *node, int strong, int internal,
1046 struct list_head *target_list)
1047 {
1048 int ret;
1049
1050 binder_node_inner_lock(node);
1051 ret = binder_inc_node_nilocked(node, strong, internal, target_list);
1052 binder_node_inner_unlock(node);
1053
1054 return ret;
1055 }
1056
binder_dec_node_nilocked(struct binder_node * node,int strong,int internal)1057 static bool binder_dec_node_nilocked(struct binder_node *node,
1058 int strong, int internal)
1059 {
1060 struct binder_proc *proc = node->proc;
1061
1062 assert_spin_locked(&node->lock);
1063 if (proc)
1064 assert_spin_locked(&proc->inner_lock);
1065 if (strong) {
1066 if (internal)
1067 node->internal_strong_refs--;
1068 else
1069 node->local_strong_refs--;
1070 if (node->local_strong_refs || node->internal_strong_refs)
1071 return false;
1072 } else {
1073 if (!internal)
1074 node->local_weak_refs--;
1075 if (node->local_weak_refs || node->tmp_refs ||
1076 !hlist_empty(&node->refs))
1077 return false;
1078 }
1079
1080 if (proc && (node->has_strong_ref || node->has_weak_ref)) {
1081 if (list_empty(&node->work.entry)) {
1082 binder_enqueue_work_ilocked(&node->work, &proc->todo);
1083 binder_wakeup_proc_ilocked(proc);
1084 }
1085 } else {
1086 if (hlist_empty(&node->refs) && !node->local_strong_refs &&
1087 !node->local_weak_refs && !node->tmp_refs) {
1088 if (proc) {
1089 binder_dequeue_work_ilocked(&node->work);
1090 rb_erase(&node->rb_node, &proc->nodes);
1091 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1092 "refless node %d deleted\n",
1093 node->debug_id);
1094 } else {
1095 BUG_ON(!list_empty(&node->work.entry));
1096 spin_lock(&binder_dead_nodes_lock);
1097 /*
1098 * tmp_refs could have changed so
1099 * check it again
1100 */
1101 if (node->tmp_refs) {
1102 spin_unlock(&binder_dead_nodes_lock);
1103 return false;
1104 }
1105 hlist_del(&node->dead_node);
1106 spin_unlock(&binder_dead_nodes_lock);
1107 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1108 "dead node %d deleted\n",
1109 node->debug_id);
1110 }
1111 return true;
1112 }
1113 }
1114 return false;
1115 }
1116
binder_dec_node(struct binder_node * node,int strong,int internal)1117 static void binder_dec_node(struct binder_node *node, int strong, int internal)
1118 {
1119 bool free_node;
1120
1121 binder_node_inner_lock(node);
1122 free_node = binder_dec_node_nilocked(node, strong, internal);
1123 binder_node_inner_unlock(node);
1124 if (free_node)
1125 binder_free_node(node);
1126 }
1127
binder_inc_node_tmpref_ilocked(struct binder_node * node)1128 static void binder_inc_node_tmpref_ilocked(struct binder_node *node)
1129 {
1130 /*
1131 * No call to binder_inc_node() is needed since we
1132 * don't need to inform userspace of any changes to
1133 * tmp_refs
1134 */
1135 node->tmp_refs++;
1136 }
1137
1138 /**
1139 * binder_inc_node_tmpref() - take a temporary reference on node
1140 * @node: node to reference
1141 *
1142 * Take reference on node to prevent the node from being freed
1143 * while referenced only by a local variable. The inner lock is
1144 * needed to serialize with the node work on the queue (which
1145 * isn't needed after the node is dead). If the node is dead
1146 * (node->proc is NULL), use binder_dead_nodes_lock to protect
1147 * node->tmp_refs against dead-node-only cases where the node
1148 * lock cannot be acquired (eg traversing the dead node list to
1149 * print nodes)
1150 */
binder_inc_node_tmpref(struct binder_node * node)1151 static void binder_inc_node_tmpref(struct binder_node *node)
1152 {
1153 binder_node_lock(node);
1154 if (node->proc)
1155 binder_inner_proc_lock(node->proc);
1156 else
1157 spin_lock(&binder_dead_nodes_lock);
1158 binder_inc_node_tmpref_ilocked(node);
1159 if (node->proc)
1160 binder_inner_proc_unlock(node->proc);
1161 else
1162 spin_unlock(&binder_dead_nodes_lock);
1163 binder_node_unlock(node);
1164 }
1165
1166 /**
1167 * binder_dec_node_tmpref() - remove a temporary reference on node
1168 * @node: node to reference
1169 *
1170 * Release temporary reference on node taken via binder_inc_node_tmpref()
1171 */
binder_dec_node_tmpref(struct binder_node * node)1172 static void binder_dec_node_tmpref(struct binder_node *node)
1173 {
1174 bool free_node;
1175
1176 binder_node_inner_lock(node);
1177 if (!node->proc)
1178 spin_lock(&binder_dead_nodes_lock);
1179 else
1180 __acquire(&binder_dead_nodes_lock);
1181 node->tmp_refs--;
1182 BUG_ON(node->tmp_refs < 0);
1183 if (!node->proc)
1184 spin_unlock(&binder_dead_nodes_lock);
1185 else
1186 __release(&binder_dead_nodes_lock);
1187 /*
1188 * Call binder_dec_node() to check if all refcounts are 0
1189 * and cleanup is needed. Calling with strong=0 and internal=1
1190 * causes no actual reference to be released in binder_dec_node().
1191 * If that changes, a change is needed here too.
1192 */
1193 free_node = binder_dec_node_nilocked(node, 0, 1);
1194 binder_node_inner_unlock(node);
1195 if (free_node)
1196 binder_free_node(node);
1197 }
1198
binder_put_node(struct binder_node * node)1199 static void binder_put_node(struct binder_node *node)
1200 {
1201 binder_dec_node_tmpref(node);
1202 }
1203
binder_get_ref_olocked(struct binder_proc * proc,u32 desc,bool need_strong_ref)1204 static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc,
1205 u32 desc, bool need_strong_ref)
1206 {
1207 struct rb_node *n = proc->refs_by_desc.rb_node;
1208 struct binder_ref *ref;
1209
1210 while (n) {
1211 ref = rb_entry(n, struct binder_ref, rb_node_desc);
1212
1213 if (desc < ref->data.desc) {
1214 n = n->rb_left;
1215 } else if (desc > ref->data.desc) {
1216 n = n->rb_right;
1217 } else if (need_strong_ref && !ref->data.strong) {
1218 binder_user_error("tried to use weak ref as strong ref\n");
1219 return NULL;
1220 } else {
1221 return ref;
1222 }
1223 }
1224 return NULL;
1225 }
1226
1227 /* Find the smallest unused descriptor the "slow way" */
slow_desc_lookup_olocked(struct binder_proc * proc,u32 offset)1228 static u32 slow_desc_lookup_olocked(struct binder_proc *proc, u32 offset)
1229 {
1230 struct binder_ref *ref;
1231 struct rb_node *n;
1232 u32 desc;
1233
1234 desc = offset;
1235 for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n)) {
1236 ref = rb_entry(n, struct binder_ref, rb_node_desc);
1237 if (ref->data.desc > desc)
1238 break;
1239 desc = ref->data.desc + 1;
1240 }
1241
1242 return desc;
1243 }
1244
1245 /*
1246 * Find an available reference descriptor ID. The proc->outer_lock might
1247 * be released in the process, in which case -EAGAIN is returned and the
1248 * @desc should be considered invalid.
1249 */
get_ref_desc_olocked(struct binder_proc * proc,struct binder_node * node,u32 * desc)1250 static int get_ref_desc_olocked(struct binder_proc *proc,
1251 struct binder_node *node,
1252 u32 *desc)
1253 {
1254 struct dbitmap *dmap = &proc->dmap;
1255 unsigned int nbits, offset;
1256 unsigned long *new, bit;
1257
1258 /* 0 is reserved for the context manager */
1259 offset = (node == proc->context->binder_context_mgr_node) ? 0 : 1;
1260
1261 if (!dbitmap_enabled(dmap)) {
1262 *desc = slow_desc_lookup_olocked(proc, offset);
1263 return 0;
1264 }
1265
1266 if (dbitmap_acquire_next_zero_bit(dmap, offset, &bit) == 0) {
1267 *desc = bit;
1268 return 0;
1269 }
1270
1271 /*
1272 * The dbitmap is full and needs to grow. The proc->outer_lock
1273 * is briefly released to allocate the new bitmap safely.
1274 */
1275 nbits = dbitmap_grow_nbits(dmap);
1276 binder_proc_unlock(proc);
1277 new = bitmap_zalloc(nbits, GFP_KERNEL);
1278 binder_proc_lock(proc);
1279 dbitmap_grow(dmap, new, nbits);
1280
1281 return -EAGAIN;
1282 }
1283
1284 /**
1285 * binder_get_ref_for_node_olocked() - get the ref associated with given node
1286 * @proc: binder_proc that owns the ref
1287 * @node: binder_node of target
1288 * @new_ref: newly allocated binder_ref to be initialized or %NULL
1289 *
1290 * Look up the ref for the given node and return it if it exists
1291 *
1292 * If it doesn't exist and the caller provides a newly allocated
1293 * ref, initialize the fields of the newly allocated ref and insert
1294 * into the given proc rb_trees and node refs list.
1295 *
1296 * Return: the ref for node. It is possible that another thread
1297 * allocated/initialized the ref first in which case the
1298 * returned ref would be different than the passed-in
1299 * new_ref. new_ref must be kfree'd by the caller in
1300 * this case.
1301 */
binder_get_ref_for_node_olocked(struct binder_proc * proc,struct binder_node * node,struct binder_ref * new_ref)1302 static struct binder_ref *binder_get_ref_for_node_olocked(
1303 struct binder_proc *proc,
1304 struct binder_node *node,
1305 struct binder_ref *new_ref)
1306 {
1307 struct binder_ref *ref;
1308 struct rb_node *parent;
1309 struct rb_node **p;
1310 u32 desc;
1311
1312 retry:
1313 p = &proc->refs_by_node.rb_node;
1314 parent = NULL;
1315 while (*p) {
1316 parent = *p;
1317 ref = rb_entry(parent, struct binder_ref, rb_node_node);
1318
1319 if (node < ref->node)
1320 p = &(*p)->rb_left;
1321 else if (node > ref->node)
1322 p = &(*p)->rb_right;
1323 else
1324 return ref;
1325 }
1326 if (!new_ref)
1327 return NULL;
1328
1329 /* might release the proc->outer_lock */
1330 if (get_ref_desc_olocked(proc, node, &desc) == -EAGAIN)
1331 goto retry;
1332
1333 binder_stats_created(BINDER_STAT_REF);
1334 new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
1335 new_ref->proc = proc;
1336 new_ref->node = node;
1337 rb_link_node(&new_ref->rb_node_node, parent, p);
1338 rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);
1339
1340 new_ref->data.desc = desc;
1341 p = &proc->refs_by_desc.rb_node;
1342 while (*p) {
1343 parent = *p;
1344 ref = rb_entry(parent, struct binder_ref, rb_node_desc);
1345
1346 if (new_ref->data.desc < ref->data.desc)
1347 p = &(*p)->rb_left;
1348 else if (new_ref->data.desc > ref->data.desc)
1349 p = &(*p)->rb_right;
1350 else
1351 BUG();
1352 }
1353 rb_link_node(&new_ref->rb_node_desc, parent, p);
1354 rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc);
1355
1356 binder_node_lock(node);
1357 hlist_add_head(&new_ref->node_entry, &node->refs);
1358
1359 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1360 "%d new ref %d desc %d for node %d\n",
1361 proc->pid, new_ref->data.debug_id, new_ref->data.desc,
1362 node->debug_id);
1363 trace_android_vh_binder_new_ref(proc, new_ref->data.desc, new_ref->node->debug_id);
1364 binder_node_unlock(node);
1365 return new_ref;
1366 }
1367
binder_cleanup_ref_olocked(struct binder_ref * ref)1368 static void binder_cleanup_ref_olocked(struct binder_ref *ref)
1369 {
1370 struct dbitmap *dmap = &ref->proc->dmap;
1371 bool delete_node = false;
1372
1373 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1374 "%d delete ref %d desc %d for node %d\n",
1375 ref->proc->pid, ref->data.debug_id, ref->data.desc,
1376 ref->node->debug_id);
1377
1378 if (dbitmap_enabled(dmap))
1379 dbitmap_clear_bit(dmap, ref->data.desc);
1380 rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
1381 rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
1382
1383 binder_node_inner_lock(ref->node);
1384 if (ref->data.strong)
1385 binder_dec_node_nilocked(ref->node, 1, 1);
1386
1387 hlist_del(&ref->node_entry);
1388 delete_node = binder_dec_node_nilocked(ref->node, 0, 1);
1389 binder_node_inner_unlock(ref->node);
1390 /*
1391 * Clear ref->node unless we want the caller to free the node
1392 */
1393 if (!delete_node) {
1394 /*
1395 * The caller uses ref->node to determine
1396 * whether the node needs to be freed. Clear
1397 * it since the node is still alive.
1398 */
1399 ref->node = NULL;
1400 }
1401
1402 if (ref->death) {
1403 binder_debug(BINDER_DEBUG_DEAD_BINDER,
1404 "%d delete ref %d desc %d has death notification\n",
1405 ref->proc->pid, ref->data.debug_id,
1406 ref->data.desc);
1407 binder_dequeue_work(ref->proc, &ref->death->work);
1408 binder_stats_deleted(BINDER_STAT_DEATH);
1409 }
1410
1411 if (ref->freeze) {
1412 binder_dequeue_work(ref->proc, &ref->freeze->work);
1413 binder_stats_deleted(BINDER_STAT_FREEZE);
1414 }
1415
1416 binder_stats_deleted(BINDER_STAT_REF);
1417 }
1418
1419 /**
1420 * binder_inc_ref_olocked() - increment the ref for given handle
1421 * @ref: ref to be incremented
1422 * @strong: if true, strong increment, else weak
1423 * @target_list: list to queue node work on
1424 *
1425 * Increment the ref. @ref->proc->outer_lock must be held on entry
1426 *
1427 * Return: 0, if successful, else errno
1428 */
binder_inc_ref_olocked(struct binder_ref * ref,int strong,struct list_head * target_list)1429 static int binder_inc_ref_olocked(struct binder_ref *ref, int strong,
1430 struct list_head *target_list)
1431 {
1432 int ret;
1433
1434 if (strong) {
1435 if (ref->data.strong == 0) {
1436 ret = binder_inc_node(ref->node, 1, 1, target_list);
1437 if (ret)
1438 return ret;
1439 }
1440 ref->data.strong++;
1441 } else {
1442 if (ref->data.weak == 0) {
1443 ret = binder_inc_node(ref->node, 0, 1, target_list);
1444 if (ret)
1445 return ret;
1446 }
1447 ref->data.weak++;
1448 }
1449 return 0;
1450 }
1451
1452 /**
1453 * binder_dec_ref_olocked() - dec the ref for given handle
1454 * @ref: ref to be decremented
1455 * @strong: if true, strong decrement, else weak
1456 *
1457 * Decrement the ref.
1458 *
1459 * Return: %true if ref is cleaned up and ready to be freed.
1460 */
binder_dec_ref_olocked(struct binder_ref * ref,int strong)1461 static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong)
1462 {
1463 if (strong) {
1464 if (ref->data.strong == 0) {
1465 binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
1466 ref->proc->pid, ref->data.debug_id,
1467 ref->data.desc, ref->data.strong,
1468 ref->data.weak);
1469 return false;
1470 }
1471 ref->data.strong--;
1472 if (ref->data.strong == 0)
1473 binder_dec_node(ref->node, strong, 1);
1474 } else {
1475 if (ref->data.weak == 0) {
1476 binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
1477 ref->proc->pid, ref->data.debug_id,
1478 ref->data.desc, ref->data.strong,
1479 ref->data.weak);
1480 return false;
1481 }
1482 ref->data.weak--;
1483 }
1484 if (ref->data.strong == 0 && ref->data.weak == 0) {
1485 binder_cleanup_ref_olocked(ref);
1486 return true;
1487 }
1488 return false;
1489 }
1490
1491 /**
1492 * binder_get_node_from_ref() - get the node from the given proc/desc
1493 * @proc: proc containing the ref
1494 * @desc: the handle associated with the ref
1495 * @need_strong_ref: if true, only return node if ref is strong
1496 * @rdata: the id/refcount data for the ref
1497 *
1498 * Given a proc and ref handle, return the associated binder_node
1499 *
1500 * Return: a binder_node or NULL if not found or not strong when strong required
1501 */
binder_get_node_from_ref(struct binder_proc * proc,u32 desc,bool need_strong_ref,struct binder_ref_data * rdata)1502 static struct binder_node *binder_get_node_from_ref(
1503 struct binder_proc *proc,
1504 u32 desc, bool need_strong_ref,
1505 struct binder_ref_data *rdata)
1506 {
1507 struct binder_node *node;
1508 struct binder_ref *ref;
1509
1510 binder_proc_lock(proc);
1511 ref = binder_get_ref_olocked(proc, desc, need_strong_ref);
1512 if (!ref)
1513 goto err_no_ref;
1514 node = ref->node;
1515 /*
1516 * Take an implicit reference on the node to ensure
1517 * it stays alive until the call to binder_put_node()
1518 */
1519 binder_inc_node_tmpref(node);
1520 if (rdata)
1521 *rdata = ref->data;
1522 binder_proc_unlock(proc);
1523
1524 return node;
1525
1526 err_no_ref:
1527 binder_proc_unlock(proc);
1528 return NULL;
1529 }
1530
1531 /**
1532 * binder_free_ref() - free the binder_ref
1533 * @ref: ref to free
1534 *
1535 * Free the binder_ref. Free the binder_node indicated by ref->node
1536 * (if non-NULL) and the binder_ref_death indicated by ref->death.
1537 */
binder_free_ref(struct binder_ref * ref)1538 static void binder_free_ref(struct binder_ref *ref)
1539 {
1540 trace_android_vh_binder_del_ref(ref->proc, ref->data.desc);
1541 if (ref->node)
1542 binder_free_node(ref->node);
1543 kfree(ref->death);
1544 kfree(ref->freeze);
1545 kfree(ref);
1546 }
1547
1548 /* shrink descriptor bitmap if needed */
try_shrink_dmap(struct binder_proc * proc)1549 static void try_shrink_dmap(struct binder_proc *proc)
1550 {
1551 unsigned long *new;
1552 int nbits;
1553
1554 binder_proc_lock(proc);
1555 nbits = dbitmap_shrink_nbits(&proc->dmap);
1556 binder_proc_unlock(proc);
1557
1558 if (!nbits)
1559 return;
1560
1561 new = bitmap_zalloc(nbits, GFP_KERNEL);
1562 binder_proc_lock(proc);
1563 dbitmap_shrink(&proc->dmap, new, nbits);
1564 binder_proc_unlock(proc);
1565 }
1566
1567 /**
1568 * binder_update_ref_for_handle() - inc/dec the ref for given handle
1569 * @proc: proc containing the ref
1570 * @desc: the handle associated with the ref
1571 * @increment: true=inc reference, false=dec reference
1572 * @strong: true=strong reference, false=weak reference
1573 * @rdata: the id/refcount data for the ref
1574 *
1575 * Given a proc and ref handle, increment or decrement the ref
1576 * according to "increment" arg.
1577 *
1578 * Return: 0 if successful, else errno
1579 */
binder_update_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool increment,bool strong,struct binder_ref_data * rdata)1580 static int binder_update_ref_for_handle(struct binder_proc *proc,
1581 uint32_t desc, bool increment, bool strong,
1582 struct binder_ref_data *rdata)
1583 {
1584 int ret = 0;
1585 struct binder_ref *ref;
1586 bool delete_ref = false;
1587
1588 binder_proc_lock(proc);
1589 ref = binder_get_ref_olocked(proc, desc, strong);
1590 if (!ref) {
1591 ret = -EINVAL;
1592 goto err_no_ref;
1593 }
1594 if (increment)
1595 ret = binder_inc_ref_olocked(ref, strong, NULL);
1596 else
1597 delete_ref = binder_dec_ref_olocked(ref, strong);
1598
1599 if (rdata)
1600 *rdata = ref->data;
1601 binder_proc_unlock(proc);
1602
1603 if (delete_ref) {
1604 binder_free_ref(ref);
1605 try_shrink_dmap(proc);
1606 }
1607 return ret;
1608
1609 err_no_ref:
1610 binder_proc_unlock(proc);
1611 return ret;
1612 }
1613
1614 /**
1615 * binder_dec_ref_for_handle() - dec the ref for given handle
1616 * @proc: proc containing the ref
1617 * @desc: the handle associated with the ref
1618 * @strong: true=strong reference, false=weak reference
1619 * @rdata: the id/refcount data for the ref
1620 *
1621 * Just calls binder_update_ref_for_handle() to decrement the ref.
1622 *
1623 * Return: 0 if successful, else errno
1624 */
binder_dec_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool strong,struct binder_ref_data * rdata)1625 static int binder_dec_ref_for_handle(struct binder_proc *proc,
1626 uint32_t desc, bool strong, struct binder_ref_data *rdata)
1627 {
1628 return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
1629 }
1630
1631
1632 /**
1633 * binder_inc_ref_for_node() - increment the ref for given proc/node
1634 * @proc: proc containing the ref
1635 * @node: target node
1636 * @strong: true=strong reference, false=weak reference
1637 * @target_list: worklist to use if node is incremented
1638 * @rdata: the id/refcount data for the ref
1639 *
1640 * Given a proc and node, increment the ref. Create the ref if it
1641 * doesn't already exist
1642 *
1643 * Return: 0 if successful, else errno
1644 */
binder_inc_ref_for_node(struct binder_proc * proc,struct binder_node * node,bool strong,struct list_head * target_list,struct binder_ref_data * rdata)1645 static int binder_inc_ref_for_node(struct binder_proc *proc,
1646 struct binder_node *node,
1647 bool strong,
1648 struct list_head *target_list,
1649 struct binder_ref_data *rdata)
1650 {
1651 struct binder_ref *ref;
1652 struct binder_ref *new_ref = NULL;
1653 int ret = 0;
1654
1655 binder_proc_lock(proc);
1656 ref = binder_get_ref_for_node_olocked(proc, node, NULL);
1657 if (!ref) {
1658 binder_proc_unlock(proc);
1659 new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
1660 if (!new_ref)
1661 return -ENOMEM;
1662 binder_proc_lock(proc);
1663 ref = binder_get_ref_for_node_olocked(proc, node, new_ref);
1664 }
1665 ret = binder_inc_ref_olocked(ref, strong, target_list);
1666 *rdata = ref->data;
1667 if (ret && ref == new_ref) {
1668 /*
1669 * Cleanup the failed reference here as the target
1670 * could now be dead and have already released its
1671 * references by now. Calling on the new reference
1672 * with strong=0 and a tmp_refs will not decrement
1673 * the node. The new_ref gets kfree'd below.
1674 */
1675 binder_cleanup_ref_olocked(new_ref);
1676 ref = NULL;
1677 }
1678
1679 binder_proc_unlock(proc);
1680 if (new_ref && ref != new_ref)
1681 /*
1682 * Another thread created the ref first so
1683 * free the one we allocated
1684 */
1685 kfree(new_ref);
1686 return ret;
1687 }
1688
binder_pop_transaction_ilocked(struct binder_thread * target_thread,struct binder_transaction * t)1689 static void binder_pop_transaction_ilocked(struct binder_thread *target_thread,
1690 struct binder_transaction *t)
1691 {
1692 BUG_ON(!target_thread);
1693 assert_spin_locked(&target_thread->proc->inner_lock);
1694 BUG_ON(target_thread->transaction_stack != t);
1695 BUG_ON(target_thread->transaction_stack->from != target_thread);
1696 target_thread->transaction_stack =
1697 target_thread->transaction_stack->from_parent;
1698 t->from = NULL;
1699 }
1700
1701 /**
1702 * binder_thread_dec_tmpref() - decrement thread->tmp_ref
1703 * @thread: thread to decrement
1704 *
1705 * A thread needs to be kept alive while being used to create or
1706 * handle a transaction. binder_get_txn_from() is used to safely
1707 * extract t->from from a binder_transaction and keep the thread
1708 * indicated by t->from from being freed. When done with that
1709 * binder_thread, this function is called to decrement the
1710 * tmp_ref and free if appropriate (thread has been released
1711 * and no transaction being processed by the driver)
1712 */
binder_thread_dec_tmpref(struct binder_thread * thread)1713 static void binder_thread_dec_tmpref(struct binder_thread *thread)
1714 {
1715 /*
1716 * atomic is used to protect the counter value while
1717 * it cannot reach zero or thread->is_dead is false
1718 */
1719 binder_inner_proc_lock(thread->proc);
1720 atomic_dec(&thread->tmp_ref);
1721 if (thread->is_dead && !atomic_read(&thread->tmp_ref)) {
1722 binder_inner_proc_unlock(thread->proc);
1723 binder_free_thread(thread);
1724 return;
1725 }
1726 binder_inner_proc_unlock(thread->proc);
1727 }
1728
1729 /**
1730 * binder_proc_dec_tmpref() - decrement proc->tmp_ref
1731 * @proc: proc to decrement
1732 *
1733 * A binder_proc needs to be kept alive while being used to create or
1734 * handle a transaction. proc->tmp_ref is incremented when
1735 * creating a new transaction or the binder_proc is currently in-use
1736 * by threads that are being released. When done with the binder_proc,
1737 * this function is called to decrement the counter and free the
1738 * proc if appropriate (proc has been released, all threads have
1739 * been released and not currently in-use to process a transaction).
1740 */
binder_proc_dec_tmpref(struct binder_proc * proc)1741 static void binder_proc_dec_tmpref(struct binder_proc *proc)
1742 {
1743 binder_inner_proc_lock(proc);
1744 proc->tmp_ref--;
1745 if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) &&
1746 !proc->tmp_ref) {
1747 binder_inner_proc_unlock(proc);
1748 binder_free_proc(proc);
1749 return;
1750 }
1751 binder_inner_proc_unlock(proc);
1752 }
1753
1754 /**
1755 * binder_get_txn_from() - safely extract the "from" thread in transaction
1756 * @t: binder transaction for t->from
1757 *
1758 * Atomically return the "from" thread and increment the tmp_ref
1759 * count for the thread to ensure it stays alive until
1760 * binder_thread_dec_tmpref() is called.
1761 *
1762 * Return: the value of t->from
1763 */
binder_get_txn_from(struct binder_transaction * t)1764 static struct binder_thread *binder_get_txn_from(
1765 struct binder_transaction *t)
1766 {
1767 struct binder_thread *from;
1768
1769 spin_lock(&t->lock);
1770 from = t->from;
1771 if (from)
1772 atomic_inc(&from->tmp_ref);
1773 spin_unlock(&t->lock);
1774 return from;
1775 }
1776
1777 /**
1778 * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock
1779 * @t: binder transaction for t->from
1780 *
1781 * Same as binder_get_txn_from() except it also acquires the proc->inner_lock
1782 * to guarantee that the thread cannot be released while operating on it.
1783 * The caller must call binder_inner_proc_unlock() to release the inner lock
1784 * as well as call binder_dec_thread_txn() to release the reference.
1785 *
1786 * Return: the value of t->from
1787 */
binder_get_txn_from_and_acq_inner(struct binder_transaction * t)1788 static struct binder_thread *binder_get_txn_from_and_acq_inner(
1789 struct binder_transaction *t)
1790 __acquires(&t->from->proc->inner_lock)
1791 {
1792 struct binder_thread *from;
1793
1794 from = binder_get_txn_from(t);
1795 if (!from) {
1796 __acquire(&from->proc->inner_lock);
1797 return NULL;
1798 }
1799 binder_inner_proc_lock(from->proc);
1800 if (t->from) {
1801 BUG_ON(from != t->from);
1802 return from;
1803 }
1804 binder_inner_proc_unlock(from->proc);
1805 __acquire(&from->proc->inner_lock);
1806 binder_thread_dec_tmpref(from);
1807 return NULL;
1808 }
1809
1810 /**
1811 * binder_free_txn_fixups() - free unprocessed fd fixups
1812 * @t: binder transaction for t->from
1813 *
1814 * If the transaction is being torn down prior to being
1815 * processed by the target process, free all of the
1816 * fd fixups and fput the file structs. It is safe to
1817 * call this function after the fixups have been
1818 * processed -- in that case, the list will be empty.
1819 */
binder_free_txn_fixups(struct binder_transaction * t)1820 static void binder_free_txn_fixups(struct binder_transaction *t)
1821 {
1822 struct binder_txn_fd_fixup *fixup, *tmp;
1823
1824 list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
1825 fput(fixup->file);
1826 if (fixup->target_fd >= 0)
1827 put_unused_fd(fixup->target_fd);
1828 list_del(&fixup->fixup_entry);
1829 kfree(fixup);
1830 }
1831 }
1832
binder_txn_latency_free(struct binder_transaction * t)1833 static void binder_txn_latency_free(struct binder_transaction *t)
1834 {
1835 int from_proc, from_thread, to_proc, to_thread;
1836
1837 spin_lock(&t->lock);
1838 from_proc = t->from ? t->from->proc->pid : 0;
1839 from_thread = t->from ? t->from->pid : 0;
1840 to_proc = t->to_proc ? t->to_proc->pid : 0;
1841 to_thread = t->to_thread ? t->to_thread->pid : 0;
1842 spin_unlock(&t->lock);
1843
1844 trace_binder_txn_latency_free(t, from_proc, from_thread, to_proc, to_thread);
1845 }
1846
binder_free_transaction(struct binder_transaction * t)1847 static void binder_free_transaction(struct binder_transaction *t)
1848 {
1849 struct binder_proc *target_proc = t->to_proc;
1850
1851 trace_android_vh_free_oem_binder_struct(t);
1852 if (target_proc) {
1853 binder_inner_proc_lock(target_proc);
1854 target_proc->outstanding_txns--;
1855 if (target_proc->outstanding_txns < 0)
1856 pr_warn("%s: Unexpected outstanding_txns %d\n",
1857 __func__, target_proc->outstanding_txns);
1858 if (!target_proc->outstanding_txns && target_proc->is_frozen)
1859 wake_up_interruptible_all(&target_proc->freeze_wait);
1860 if (t->buffer)
1861 t->buffer->transaction = NULL;
1862 binder_inner_proc_unlock(target_proc);
1863 }
1864 if (trace_binder_txn_latency_free_enabled())
1865 binder_txn_latency_free(t);
1866 /*
1867 * If the transaction has no target_proc, then
1868 * t->buffer->transaction has already been cleared.
1869 */
1870 binder_free_txn_fixups(t);
1871 kfree(t);
1872 binder_stats_deleted(BINDER_STAT_TRANSACTION);
1873 }
1874
binder_send_failed_reply(struct binder_transaction * t,uint32_t error_code)1875 static void binder_send_failed_reply(struct binder_transaction *t,
1876 uint32_t error_code)
1877 {
1878 struct binder_thread *target_thread;
1879 struct binder_transaction *next;
1880
1881 BUG_ON(t->flags & TF_ONE_WAY);
1882 while (1) {
1883 target_thread = binder_get_txn_from_and_acq_inner(t);
1884 if (target_thread) {
1885 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1886 "send failed reply for transaction %d to %d:%d\n",
1887 t->debug_id,
1888 target_thread->proc->pid,
1889 target_thread->pid);
1890
1891 binder_pop_transaction_ilocked(target_thread, t);
1892 if (target_thread->reply_error.cmd == BR_OK) {
1893 target_thread->reply_error.cmd = error_code;
1894 binder_enqueue_thread_work_ilocked(
1895 target_thread,
1896 &target_thread->reply_error.work);
1897 wake_up_interruptible(&target_thread->wait);
1898 } else {
1899 /*
1900 * Cannot get here for normal operation, but
1901 * we can if multiple synchronous transactions
1902 * are sent without blocking for responses.
1903 * Just ignore the 2nd error in this case.
1904 */
1905 pr_warn("Unexpected reply error: %u\n",
1906 target_thread->reply_error.cmd);
1907 }
1908 binder_inner_proc_unlock(target_thread->proc);
1909 binder_thread_dec_tmpref(target_thread);
1910 binder_free_transaction(t);
1911 return;
1912 }
1913 __release(&target_thread->proc->inner_lock);
1914 next = t->from_parent;
1915
1916 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1917 "send failed reply for transaction %d, target dead\n",
1918 t->debug_id);
1919
1920 binder_free_transaction(t);
1921 if (next == NULL) {
1922 binder_debug(BINDER_DEBUG_DEAD_BINDER,
1923 "reply failed, no target thread at root\n");
1924 return;
1925 }
1926 t = next;
1927 binder_debug(BINDER_DEBUG_DEAD_BINDER,
1928 "reply failed, no target thread -- retry %d\n",
1929 t->debug_id);
1930 }
1931 }
1932
1933 /**
1934 * binder_cleanup_transaction() - cleans up undelivered transaction
1935 * @t: transaction that needs to be cleaned up
1936 * @reason: reason the transaction wasn't delivered
1937 * @error_code: error to return to caller (if synchronous call)
1938 */
binder_cleanup_transaction(struct binder_transaction * t,const char * reason,uint32_t error_code)1939 static void binder_cleanup_transaction(struct binder_transaction *t,
1940 const char *reason,
1941 uint32_t error_code)
1942 {
1943 if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
1944 binder_send_failed_reply(t, error_code);
1945 } else {
1946 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
1947 "undelivered transaction %d, %s\n",
1948 t->debug_id, reason);
1949 binder_free_transaction(t);
1950 }
1951 }
1952
1953 /**
1954 * binder_get_object() - gets object and checks for valid metadata
1955 * @proc: binder_proc owning the buffer
1956 * @u: sender's user pointer to base of buffer
1957 * @buffer: binder_buffer that we're parsing.
1958 * @offset: offset in the @buffer at which to validate an object.
1959 * @object: struct binder_object to read into
1960 *
1961 * Copy the binder object at the given offset into @object. If @u is
1962 * provided then the copy is from the sender's buffer. If not, then
1963 * it is copied from the target's @buffer.
1964 *
1965 * Return: If there's a valid metadata object at @offset, the
1966 * size of that object. Otherwise, it returns zero. The object
1967 * is read into the struct binder_object pointed to by @object.
1968 */
binder_get_object(struct binder_proc * proc,const void __user * u,struct binder_buffer * buffer,unsigned long offset,struct binder_object * object)1969 static size_t binder_get_object(struct binder_proc *proc,
1970 const void __user *u,
1971 struct binder_buffer *buffer,
1972 unsigned long offset,
1973 struct binder_object *object)
1974 {
1975 size_t read_size;
1976 struct binder_object_header *hdr;
1977 size_t object_size = 0;
1978
1979 read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset);
1980 if (offset > buffer->data_size || read_size < sizeof(*hdr) ||
1981 !IS_ALIGNED(offset, sizeof(u32)))
1982 return 0;
1983
1984 if (u) {
1985 if (copy_from_user(object, u + offset, read_size))
1986 return 0;
1987 } else {
1988 if (binder_alloc_copy_from_buffer(&proc->alloc, object, buffer,
1989 offset, read_size))
1990 return 0;
1991 }
1992
1993 /* Ok, now see if we read a complete object. */
1994 hdr = &object->hdr;
1995 switch (hdr->type) {
1996 case BINDER_TYPE_BINDER:
1997 case BINDER_TYPE_WEAK_BINDER:
1998 case BINDER_TYPE_HANDLE:
1999 case BINDER_TYPE_WEAK_HANDLE:
2000 object_size = sizeof(struct flat_binder_object);
2001 break;
2002 case BINDER_TYPE_FD:
2003 object_size = sizeof(struct binder_fd_object);
2004 break;
2005 case BINDER_TYPE_PTR:
2006 object_size = sizeof(struct binder_buffer_object);
2007 break;
2008 case BINDER_TYPE_FDA:
2009 object_size = sizeof(struct binder_fd_array_object);
2010 break;
2011 default:
2012 return 0;
2013 }
2014 if (offset <= buffer->data_size - object_size &&
2015 buffer->data_size >= object_size)
2016 return object_size;
2017 else
2018 return 0;
2019 }
2020
2021 /**
2022 * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer.
2023 * @proc: binder_proc owning the buffer
2024 * @b: binder_buffer containing the object
2025 * @object: struct binder_object to read into
2026 * @index: index in offset array at which the binder_buffer_object is
2027 * located
2028 * @start_offset: points to the start of the offset array
2029 * @object_offsetp: offset of @object read from @b
2030 * @num_valid: the number of valid offsets in the offset array
2031 *
2032 * Return: If @index is within the valid range of the offset array
2033 * described by @start and @num_valid, and if there's a valid
2034 * binder_buffer_object at the offset found in index @index
2035 * of the offset array, that object is returned. Otherwise,
2036 * %NULL is returned.
2037 * Note that the offset found in index @index itself is not
2038 * verified; this function assumes that @num_valid elements
2039 * from @start were previously verified to have valid offsets.
2040 * If @object_offsetp is non-NULL, then the offset within
2041 * @b is written to it.
2042 */
binder_validate_ptr(struct binder_proc * proc,struct binder_buffer * b,struct binder_object * object,binder_size_t index,binder_size_t start_offset,binder_size_t * object_offsetp,binder_size_t num_valid)2043 static struct binder_buffer_object *binder_validate_ptr(
2044 struct binder_proc *proc,
2045 struct binder_buffer *b,
2046 struct binder_object *object,
2047 binder_size_t index,
2048 binder_size_t start_offset,
2049 binder_size_t *object_offsetp,
2050 binder_size_t num_valid)
2051 {
2052 size_t object_size;
2053 binder_size_t object_offset;
2054 unsigned long buffer_offset;
2055
2056 if (index >= num_valid)
2057 return NULL;
2058
2059 buffer_offset = start_offset + sizeof(binder_size_t) * index;
2060 if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
2061 b, buffer_offset,
2062 sizeof(object_offset)))
2063 return NULL;
2064 object_size = binder_get_object(proc, NULL, b, object_offset, object);
2065 if (!object_size || object->hdr.type != BINDER_TYPE_PTR)
2066 return NULL;
2067 if (object_offsetp)
2068 *object_offsetp = object_offset;
2069
2070 return &object->bbo;
2071 }
2072
2073 /**
2074 * binder_validate_fixup() - validates pointer/fd fixups happen in order.
2075 * @proc: binder_proc owning the buffer
2076 * @b: transaction buffer
2077 * @objects_start_offset: offset to start of objects buffer
2078 * @buffer_obj_offset: offset to binder_buffer_object in which to fix up
2079 * @fixup_offset: start offset in @buffer to fix up
2080 * @last_obj_offset: offset to last binder_buffer_object that we fixed
2081 * @last_min_offset: minimum fixup offset in object at @last_obj_offset
2082 *
2083 * Return: %true if a fixup in buffer @buffer at offset @offset is
2084 * allowed.
2085 *
2086 * For safety reasons, we only allow fixups inside a buffer to happen
2087 * at increasing offsets; additionally, we only allow fixup on the last
2088 * buffer object that was verified, or one of its parents.
2089 *
2090 * Example of what is allowed:
2091 *
2092 * A
2093 * B (parent = A, offset = 0)
2094 * C (parent = A, offset = 16)
2095 * D (parent = C, offset = 0)
2096 * E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset)
2097 *
2098 * Examples of what is not allowed:
2099 *
2100 * Decreasing offsets within the same parent:
2101 * A
2102 * C (parent = A, offset = 16)
2103 * B (parent = A, offset = 0) // decreasing offset within A
2104 *
2105 * Referring to a parent that wasn't the last object or any of its parents:
2106 * A
2107 * B (parent = A, offset = 0)
2108 * C (parent = A, offset = 0)
2109 * C (parent = A, offset = 16)
2110 * D (parent = B, offset = 0) // B is not A or any of A's parents
2111 */
binder_validate_fixup(struct binder_proc * proc,struct binder_buffer * b,binder_size_t objects_start_offset,binder_size_t buffer_obj_offset,binder_size_t fixup_offset,binder_size_t last_obj_offset,binder_size_t last_min_offset)2112 static bool binder_validate_fixup(struct binder_proc *proc,
2113 struct binder_buffer *b,
2114 binder_size_t objects_start_offset,
2115 binder_size_t buffer_obj_offset,
2116 binder_size_t fixup_offset,
2117 binder_size_t last_obj_offset,
2118 binder_size_t last_min_offset)
2119 {
2120 if (!last_obj_offset) {
2121 /* Nothing to fix up in */
2122 return false;
2123 }
2124
2125 while (last_obj_offset != buffer_obj_offset) {
2126 unsigned long buffer_offset;
2127 struct binder_object last_object;
2128 struct binder_buffer_object *last_bbo;
2129 size_t object_size = binder_get_object(proc, NULL, b,
2130 last_obj_offset,
2131 &last_object);
2132 if (object_size != sizeof(*last_bbo))
2133 return false;
2134
2135 last_bbo = &last_object.bbo;
2136 /*
2137 * Safe to retrieve the parent of last_obj, since it
2138 * was already previously verified by the driver.
2139 */
2140 if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0)
2141 return false;
2142 last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t);
2143 buffer_offset = objects_start_offset +
2144 sizeof(binder_size_t) * last_bbo->parent;
2145 if (binder_alloc_copy_from_buffer(&proc->alloc,
2146 &last_obj_offset,
2147 b, buffer_offset,
2148 sizeof(last_obj_offset)))
2149 return false;
2150 }
2151 return (fixup_offset >= last_min_offset);
2152 }
2153
2154 /**
2155 * struct binder_task_work_cb - for deferred close
2156 *
2157 * @twork: callback_head for task work
2158 * @fd: fd to close
2159 *
2160 * Structure to pass task work to be handled after
2161 * returning from binder_ioctl() via task_work_add().
2162 */
2163 struct binder_task_work_cb {
2164 struct callback_head twork;
2165 struct file *file;
2166 };
2167
2168 /**
2169 * binder_do_fd_close() - close list of file descriptors
2170 * @twork: callback head for task work
2171 *
2172 * It is not safe to call ksys_close() during the binder_ioctl()
2173 * function if there is a chance that binder's own file descriptor
2174 * might be closed. This is to meet the requirements for using
2175 * fdget() (see comments for __fget_light()). Therefore use
2176 * task_work_add() to schedule the close operation once we have
2177 * returned from binder_ioctl(). This function is a callback
2178 * for that mechanism and does the actual ksys_close() on the
2179 * given file descriptor.
2180 */
binder_do_fd_close(struct callback_head * twork)2181 static void binder_do_fd_close(struct callback_head *twork)
2182 {
2183 struct binder_task_work_cb *twcb = container_of(twork,
2184 struct binder_task_work_cb, twork);
2185
2186 fput(twcb->file);
2187 kfree(twcb);
2188 }
2189
2190 /**
2191 * binder_deferred_fd_close() - schedule a close for the given file-descriptor
2192 * @fd: file-descriptor to close
2193 *
2194 * See comments in binder_do_fd_close(). This function is used to schedule
2195 * a file-descriptor to be closed after returning from binder_ioctl().
2196 */
binder_deferred_fd_close(int fd)2197 static void binder_deferred_fd_close(int fd)
2198 {
2199 struct binder_task_work_cb *twcb;
2200
2201 twcb = kzalloc(sizeof(*twcb), GFP_KERNEL);
2202 if (!twcb)
2203 return;
2204 init_task_work(&twcb->twork, binder_do_fd_close);
2205 twcb->file = file_close_fd(fd);
2206 if (twcb->file) {
2207 // pin it until binder_do_fd_close(); see comments there
2208 get_file(twcb->file);
2209 filp_close(twcb->file, current->files);
2210 task_work_add(current, &twcb->twork, TWA_RESUME);
2211 } else {
2212 kfree(twcb);
2213 }
2214 }
2215
binder_transaction_buffer_release(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,binder_size_t off_end_offset,bool is_failure)2216 static void binder_transaction_buffer_release(struct binder_proc *proc,
2217 struct binder_thread *thread,
2218 struct binder_buffer *buffer,
2219 binder_size_t off_end_offset,
2220 bool is_failure)
2221 {
2222 int debug_id = buffer->debug_id;
2223 binder_size_t off_start_offset, buffer_offset;
2224
2225 binder_debug(BINDER_DEBUG_TRANSACTION,
2226 "%d buffer release %d, size %zd-%zd, failed at %llx\n",
2227 proc->pid, buffer->debug_id,
2228 buffer->data_size, buffer->offsets_size,
2229 (unsigned long long)off_end_offset);
2230
2231 if (buffer->target_node)
2232 binder_dec_node(buffer->target_node, 1, 0);
2233
2234 off_start_offset = ALIGN(buffer->data_size, sizeof(void *));
2235
2236 for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
2237 buffer_offset += sizeof(binder_size_t)) {
2238 struct binder_object_header *hdr;
2239 size_t object_size = 0;
2240 struct binder_object object;
2241 binder_size_t object_offset;
2242
2243 if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
2244 buffer, buffer_offset,
2245 sizeof(object_offset)))
2246 object_size = binder_get_object(proc, NULL, buffer,
2247 object_offset, &object);
2248 if (object_size == 0) {
2249 pr_err("transaction release %d bad object at offset %lld, size %zd\n",
2250 debug_id, (u64)object_offset, buffer->data_size);
2251 continue;
2252 }
2253 hdr = &object.hdr;
2254 switch (hdr->type) {
2255 case BINDER_TYPE_BINDER:
2256 case BINDER_TYPE_WEAK_BINDER: {
2257 struct flat_binder_object *fp;
2258 struct binder_node *node;
2259
2260 fp = to_flat_binder_object(hdr);
2261 node = binder_get_node(proc, fp->binder);
2262 if (node == NULL) {
2263 pr_err("transaction release %d bad node %016llx\n",
2264 debug_id, (u64)fp->binder);
2265 break;
2266 }
2267 binder_debug(BINDER_DEBUG_TRANSACTION,
2268 " node %d u%016llx\n",
2269 node->debug_id, (u64)node->ptr);
2270 binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER,
2271 0);
2272 binder_put_node(node);
2273 } break;
2274 case BINDER_TYPE_HANDLE:
2275 case BINDER_TYPE_WEAK_HANDLE: {
2276 struct flat_binder_object *fp;
2277 struct binder_ref_data rdata;
2278 int ret;
2279
2280 fp = to_flat_binder_object(hdr);
2281 ret = binder_dec_ref_for_handle(proc, fp->handle,
2282 hdr->type == BINDER_TYPE_HANDLE, &rdata);
2283
2284 if (ret) {
2285 pr_err("transaction release %d bad handle %d, ret = %d\n",
2286 debug_id, fp->handle, ret);
2287 break;
2288 }
2289 binder_debug(BINDER_DEBUG_TRANSACTION,
2290 " ref %d desc %d\n",
2291 rdata.debug_id, rdata.desc);
2292 } break;
2293
2294 case BINDER_TYPE_FD: {
2295 /*
2296 * No need to close the file here since user-space
2297 * closes it for successfully delivered
2298 * transactions. For transactions that weren't
2299 * delivered, the new fd was never allocated so
2300 * there is no need to close and the fput on the
2301 * file is done when the transaction is torn
2302 * down.
2303 */
2304 } break;
2305 case BINDER_TYPE_PTR:
2306 /*
2307 * Nothing to do here, this will get cleaned up when the
2308 * transaction buffer gets freed
2309 */
2310 break;
2311 case BINDER_TYPE_FDA: {
2312 struct binder_fd_array_object *fda;
2313 struct binder_buffer_object *parent;
2314 struct binder_object ptr_object;
2315 binder_size_t fda_offset;
2316 size_t fd_index;
2317 binder_size_t fd_buf_size;
2318 binder_size_t num_valid;
2319
2320 if (is_failure) {
2321 /*
2322 * The fd fixups have not been applied so no
2323 * fds need to be closed.
2324 */
2325 continue;
2326 }
2327
2328 num_valid = (buffer_offset - off_start_offset) /
2329 sizeof(binder_size_t);
2330 fda = to_binder_fd_array_object(hdr);
2331 parent = binder_validate_ptr(proc, buffer, &ptr_object,
2332 fda->parent,
2333 off_start_offset,
2334 NULL,
2335 num_valid);
2336 if (!parent) {
2337 pr_err("transaction release %d bad parent offset\n",
2338 debug_id);
2339 continue;
2340 }
2341 fd_buf_size = sizeof(u32) * fda->num_fds;
2342 if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2343 pr_err("transaction release %d invalid number of fds (%lld)\n",
2344 debug_id, (u64)fda->num_fds);
2345 continue;
2346 }
2347 if (fd_buf_size > parent->length ||
2348 fda->parent_offset > parent->length - fd_buf_size) {
2349 /* No space for all file descriptors here. */
2350 pr_err("transaction release %d not enough space for %lld fds in buffer\n",
2351 debug_id, (u64)fda->num_fds);
2352 continue;
2353 }
2354 /*
2355 * the source data for binder_buffer_object is visible
2356 * to user-space and the @buffer element is the user
2357 * pointer to the buffer_object containing the fd_array.
2358 * Convert the address to an offset relative to
2359 * the base of the transaction buffer.
2360 */
2361 fda_offset = parent->buffer - buffer->user_data +
2362 fda->parent_offset;
2363 for (fd_index = 0; fd_index < fda->num_fds;
2364 fd_index++) {
2365 u32 fd;
2366 int err;
2367 binder_size_t offset = fda_offset +
2368 fd_index * sizeof(fd);
2369
2370 err = binder_alloc_copy_from_buffer(
2371 &proc->alloc, &fd, buffer,
2372 offset, sizeof(fd));
2373 WARN_ON(err);
2374 if (!err) {
2375 binder_deferred_fd_close(fd);
2376 /*
2377 * Need to make sure the thread goes
2378 * back to userspace to complete the
2379 * deferred close
2380 */
2381 if (thread)
2382 thread->looper_need_return = true;
2383 }
2384 }
2385 } break;
2386 default:
2387 pr_err("transaction release %d bad object type %x\n",
2388 debug_id, hdr->type);
2389 break;
2390 }
2391 }
2392 }
2393
2394 /* Clean up all the objects in the buffer */
binder_release_entire_buffer(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)2395 static inline void binder_release_entire_buffer(struct binder_proc *proc,
2396 struct binder_thread *thread,
2397 struct binder_buffer *buffer,
2398 bool is_failure)
2399 {
2400 binder_size_t off_end_offset;
2401
2402 off_end_offset = ALIGN(buffer->data_size, sizeof(void *));
2403 off_end_offset += buffer->offsets_size;
2404
2405 binder_transaction_buffer_release(proc, thread, buffer,
2406 off_end_offset, is_failure);
2407 }
2408
binder_translate_binder(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2409 static int binder_translate_binder(struct flat_binder_object *fp,
2410 struct binder_transaction *t,
2411 struct binder_thread *thread)
2412 {
2413 struct binder_node *node;
2414 struct binder_proc *proc = thread->proc;
2415 struct binder_proc *target_proc = t->to_proc;
2416 struct binder_ref_data rdata;
2417 int ret = 0;
2418
2419 node = binder_get_node(proc, fp->binder);
2420 if (!node) {
2421 node = binder_new_node(proc, fp);
2422 if (!node)
2423 return -ENOMEM;
2424 }
2425 if (fp->cookie != node->cookie) {
2426 binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n",
2427 proc->pid, thread->pid, (u64)fp->binder,
2428 node->debug_id, (u64)fp->cookie,
2429 (u64)node->cookie);
2430 ret = -EINVAL;
2431 goto done;
2432 }
2433 if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2434 ret = -EPERM;
2435 goto done;
2436 }
2437
2438 ret = binder_inc_ref_for_node(target_proc, node,
2439 fp->hdr.type == BINDER_TYPE_BINDER,
2440 &thread->todo, &rdata);
2441 if (ret)
2442 goto done;
2443
2444 if (fp->hdr.type == BINDER_TYPE_BINDER)
2445 fp->hdr.type = BINDER_TYPE_HANDLE;
2446 else
2447 fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
2448 fp->binder = 0;
2449 fp->handle = rdata.desc;
2450 fp->cookie = 0;
2451
2452 trace_binder_transaction_node_to_ref(t, node, &rdata);
2453 binder_debug(BINDER_DEBUG_TRANSACTION,
2454 " node %d u%016llx -> ref %d desc %d\n",
2455 node->debug_id, (u64)node->ptr,
2456 rdata.debug_id, rdata.desc);
2457 done:
2458 binder_put_node(node);
2459 return ret;
2460 }
2461
binder_translate_handle(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2462 static int binder_translate_handle(struct flat_binder_object *fp,
2463 struct binder_transaction *t,
2464 struct binder_thread *thread)
2465 {
2466 struct binder_proc *proc = thread->proc;
2467 struct binder_proc *target_proc = t->to_proc;
2468 struct binder_node *node;
2469 struct binder_ref_data src_rdata;
2470 int ret = 0;
2471
2472 node = binder_get_node_from_ref(proc, fp->handle,
2473 fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
2474 if (!node) {
2475 binder_user_error("%d:%d got transaction with invalid handle, %d\n",
2476 proc->pid, thread->pid, fp->handle);
2477 return -EINVAL;
2478 }
2479 if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2480 ret = -EPERM;
2481 goto done;
2482 }
2483
2484 binder_node_lock(node);
2485 if (node->proc == target_proc) {
2486 if (fp->hdr.type == BINDER_TYPE_HANDLE)
2487 fp->hdr.type = BINDER_TYPE_BINDER;
2488 else
2489 fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
2490 fp->binder = node->ptr;
2491 fp->cookie = node->cookie;
2492 if (node->proc)
2493 binder_inner_proc_lock(node->proc);
2494 else
2495 __acquire(&node->proc->inner_lock);
2496 binder_inc_node_nilocked(node,
2497 fp->hdr.type == BINDER_TYPE_BINDER,
2498 0, NULL);
2499 if (node->proc)
2500 binder_inner_proc_unlock(node->proc);
2501 else
2502 __release(&node->proc->inner_lock);
2503 trace_binder_transaction_ref_to_node(t, node, &src_rdata);
2504 binder_debug(BINDER_DEBUG_TRANSACTION,
2505 " ref %d desc %d -> node %d u%016llx\n",
2506 src_rdata.debug_id, src_rdata.desc, node->debug_id,
2507 (u64)node->ptr);
2508 binder_node_unlock(node);
2509 } else {
2510 struct binder_ref_data dest_rdata;
2511
2512 binder_node_unlock(node);
2513 ret = binder_inc_ref_for_node(target_proc, node,
2514 fp->hdr.type == BINDER_TYPE_HANDLE,
2515 NULL, &dest_rdata);
2516 if (ret)
2517 goto done;
2518
2519 fp->binder = 0;
2520 fp->handle = dest_rdata.desc;
2521 fp->cookie = 0;
2522 trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
2523 &dest_rdata);
2524 binder_debug(BINDER_DEBUG_TRANSACTION,
2525 " ref %d desc %d -> ref %d desc %d (node %d)\n",
2526 src_rdata.debug_id, src_rdata.desc,
2527 dest_rdata.debug_id, dest_rdata.desc,
2528 node->debug_id);
2529 }
2530 done:
2531 binder_put_node(node);
2532 return ret;
2533 }
2534
binder_translate_fd(u32 fd,binder_size_t fd_offset,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2535 static int binder_translate_fd(u32 fd, binder_size_t fd_offset,
2536 struct binder_transaction *t,
2537 struct binder_thread *thread,
2538 struct binder_transaction *in_reply_to)
2539 {
2540 struct binder_proc *proc = thread->proc;
2541 struct binder_proc *target_proc = t->to_proc;
2542 struct binder_txn_fd_fixup *fixup;
2543 struct file *file;
2544 int ret = 0;
2545 bool target_allows_fd;
2546
2547 if (in_reply_to)
2548 target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
2549 else
2550 target_allows_fd = t->buffer->target_node->accept_fds;
2551 if (!target_allows_fd) {
2552 binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n",
2553 proc->pid, thread->pid,
2554 in_reply_to ? "reply" : "transaction",
2555 fd);
2556 ret = -EPERM;
2557 goto err_fd_not_accepted;
2558 }
2559
2560 file = fget(fd);
2561 if (!file) {
2562 binder_user_error("%d:%d got transaction with invalid fd, %d\n",
2563 proc->pid, thread->pid, fd);
2564 ret = -EBADF;
2565 goto err_fget;
2566 }
2567 ret = security_binder_transfer_file(proc->cred, target_proc->cred, file);
2568 if (ret < 0) {
2569 ret = -EPERM;
2570 goto err_security;
2571 }
2572
2573 /*
2574 * Add fixup record for this transaction. The allocation
2575 * of the fd in the target needs to be done from a
2576 * target thread.
2577 */
2578 fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
2579 if (!fixup) {
2580 ret = -ENOMEM;
2581 goto err_alloc;
2582 }
2583 fixup->file = file;
2584 fixup->offset = fd_offset;
2585 fixup->target_fd = -1;
2586 trace_binder_transaction_fd_send(t, fd, fixup->offset);
2587 list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
2588
2589 return ret;
2590
2591 err_alloc:
2592 err_security:
2593 fput(file);
2594 err_fget:
2595 err_fd_not_accepted:
2596 return ret;
2597 }
2598
2599 /**
2600 * struct binder_ptr_fixup - data to be fixed-up in target buffer
2601 * @offset offset in target buffer to fixup
2602 * @skip_size bytes to skip in copy (fixup will be written later)
2603 * @fixup_data data to write at fixup offset
2604 * @node list node
2605 *
2606 * This is used for the pointer fixup list (pf) which is created and consumed
2607 * during binder_transaction() and is only accessed locally. No
2608 * locking is necessary.
2609 *
2610 * The list is ordered by @offset.
2611 */
2612 struct binder_ptr_fixup {
2613 binder_size_t offset;
2614 size_t skip_size;
2615 binder_uintptr_t fixup_data;
2616 struct list_head node;
2617 };
2618
2619 /**
2620 * struct binder_sg_copy - scatter-gather data to be copied
2621 * @offset offset in target buffer
2622 * @sender_uaddr user address in source buffer
2623 * @length bytes to copy
2624 * @node list node
2625 *
2626 * This is used for the sg copy list (sgc) which is created and consumed
2627 * during binder_transaction() and is only accessed locally. No
2628 * locking is necessary.
2629 *
2630 * The list is ordered by @offset.
2631 */
2632 struct binder_sg_copy {
2633 binder_size_t offset;
2634 const void __user *sender_uaddr;
2635 size_t length;
2636 struct list_head node;
2637 };
2638
2639 /**
2640 * binder_do_deferred_txn_copies() - copy and fixup scatter-gather data
2641 * @alloc: binder_alloc associated with @buffer
2642 * @buffer: binder buffer in target process
2643 * @sgc_head: list_head of scatter-gather copy list
2644 * @pf_head: list_head of pointer fixup list
2645 *
2646 * Processes all elements of @sgc_head, applying fixups from @pf_head
2647 * and copying the scatter-gather data from the source process' user
2648 * buffer to the target's buffer. It is expected that the list creation
2649 * and processing all occurs during binder_transaction() so these lists
2650 * are only accessed in local context.
2651 *
2652 * Return: 0=success, else -errno
2653 */
binder_do_deferred_txn_copies(struct binder_alloc * alloc,struct binder_buffer * buffer,struct list_head * sgc_head,struct list_head * pf_head)2654 static int binder_do_deferred_txn_copies(struct binder_alloc *alloc,
2655 struct binder_buffer *buffer,
2656 struct list_head *sgc_head,
2657 struct list_head *pf_head)
2658 {
2659 int ret = 0;
2660 struct binder_sg_copy *sgc, *tmpsgc;
2661 struct binder_ptr_fixup *tmppf;
2662 struct binder_ptr_fixup *pf =
2663 list_first_entry_or_null(pf_head, struct binder_ptr_fixup,
2664 node);
2665
2666 list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2667 size_t bytes_copied = 0;
2668
2669 while (bytes_copied < sgc->length) {
2670 size_t copy_size;
2671 size_t bytes_left = sgc->length - bytes_copied;
2672 size_t offset = sgc->offset + bytes_copied;
2673
2674 /*
2675 * We copy up to the fixup (pointed to by pf)
2676 */
2677 copy_size = pf ? min(bytes_left, (size_t)pf->offset - offset)
2678 : bytes_left;
2679 if (!ret && copy_size)
2680 ret = binder_alloc_copy_user_to_buffer(
2681 alloc, buffer,
2682 offset,
2683 sgc->sender_uaddr + bytes_copied,
2684 copy_size);
2685 bytes_copied += copy_size;
2686 if (copy_size != bytes_left) {
2687 BUG_ON(!pf);
2688 /* we stopped at a fixup offset */
2689 if (pf->skip_size) {
2690 /*
2691 * we are just skipping. This is for
2692 * BINDER_TYPE_FDA where the translated
2693 * fds will be fixed up when we get
2694 * to target context.
2695 */
2696 bytes_copied += pf->skip_size;
2697 } else {
2698 /* apply the fixup indicated by pf */
2699 if (!ret)
2700 ret = binder_alloc_copy_to_buffer(
2701 alloc, buffer,
2702 pf->offset,
2703 &pf->fixup_data,
2704 sizeof(pf->fixup_data));
2705 bytes_copied += sizeof(pf->fixup_data);
2706 }
2707 list_del(&pf->node);
2708 kfree(pf);
2709 pf = list_first_entry_or_null(pf_head,
2710 struct binder_ptr_fixup, node);
2711 }
2712 }
2713 list_del(&sgc->node);
2714 kfree(sgc);
2715 }
2716 list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2717 BUG_ON(pf->skip_size == 0);
2718 list_del(&pf->node);
2719 kfree(pf);
2720 }
2721 BUG_ON(!list_empty(sgc_head));
2722
2723 return ret > 0 ? -EINVAL : ret;
2724 }
2725
2726 /**
2727 * binder_cleanup_deferred_txn_lists() - free specified lists
2728 * @sgc_head: list_head of scatter-gather copy list
2729 * @pf_head: list_head of pointer fixup list
2730 *
2731 * Called to clean up @sgc_head and @pf_head if there is an
2732 * error.
2733 */
binder_cleanup_deferred_txn_lists(struct list_head * sgc_head,struct list_head * pf_head)2734 static void binder_cleanup_deferred_txn_lists(struct list_head *sgc_head,
2735 struct list_head *pf_head)
2736 {
2737 struct binder_sg_copy *sgc, *tmpsgc;
2738 struct binder_ptr_fixup *pf, *tmppf;
2739
2740 list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2741 list_del(&sgc->node);
2742 kfree(sgc);
2743 }
2744 list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2745 list_del(&pf->node);
2746 kfree(pf);
2747 }
2748 }
2749
2750 /**
2751 * binder_defer_copy() - queue a scatter-gather buffer for copy
2752 * @sgc_head: list_head of scatter-gather copy list
2753 * @offset: binder buffer offset in target process
2754 * @sender_uaddr: user address in source process
2755 * @length: bytes to copy
2756 *
2757 * Specify a scatter-gather block to be copied. The actual copy must
2758 * be deferred until all the needed fixups are identified and queued.
2759 * Then the copy and fixups are done together so un-translated values
2760 * from the source are never visible in the target buffer.
2761 *
2762 * We are guaranteed that repeated calls to this function will have
2763 * monotonically increasing @offset values so the list will naturally
2764 * be ordered.
2765 *
2766 * Return: 0=success, else -errno
2767 */
binder_defer_copy(struct list_head * sgc_head,binder_size_t offset,const void __user * sender_uaddr,size_t length)2768 static int binder_defer_copy(struct list_head *sgc_head, binder_size_t offset,
2769 const void __user *sender_uaddr, size_t length)
2770 {
2771 struct binder_sg_copy *bc = kzalloc(sizeof(*bc), GFP_KERNEL);
2772
2773 if (!bc)
2774 return -ENOMEM;
2775
2776 bc->offset = offset;
2777 bc->sender_uaddr = sender_uaddr;
2778 bc->length = length;
2779 INIT_LIST_HEAD(&bc->node);
2780
2781 /*
2782 * We are guaranteed that the deferred copies are in-order
2783 * so just add to the tail.
2784 */
2785 list_add_tail(&bc->node, sgc_head);
2786
2787 return 0;
2788 }
2789
2790 /**
2791 * binder_add_fixup() - queue a fixup to be applied to sg copy
2792 * @pf_head: list_head of binder ptr fixup list
2793 * @offset: binder buffer offset in target process
2794 * @fixup: bytes to be copied for fixup
2795 * @skip_size: bytes to skip when copying (fixup will be applied later)
2796 *
2797 * Add the specified fixup to a list ordered by @offset. When copying
2798 * the scatter-gather buffers, the fixup will be copied instead of
2799 * data from the source buffer. For BINDER_TYPE_FDA fixups, the fixup
2800 * will be applied later (in target process context), so we just skip
2801 * the bytes specified by @skip_size. If @skip_size is 0, we copy the
2802 * value in @fixup.
2803 *
2804 * This function is called *mostly* in @offset order, but there are
2805 * exceptions. Since out-of-order inserts are relatively uncommon,
2806 * we insert the new element by searching backward from the tail of
2807 * the list.
2808 *
2809 * Return: 0=success, else -errno
2810 */
binder_add_fixup(struct list_head * pf_head,binder_size_t offset,binder_uintptr_t fixup,size_t skip_size)2811 static int binder_add_fixup(struct list_head *pf_head, binder_size_t offset,
2812 binder_uintptr_t fixup, size_t skip_size)
2813 {
2814 struct binder_ptr_fixup *pf = kzalloc(sizeof(*pf), GFP_KERNEL);
2815 struct binder_ptr_fixup *tmppf;
2816
2817 if (!pf)
2818 return -ENOMEM;
2819
2820 pf->offset = offset;
2821 pf->fixup_data = fixup;
2822 pf->skip_size = skip_size;
2823 INIT_LIST_HEAD(&pf->node);
2824
2825 /* Fixups are *mostly* added in-order, but there are some
2826 * exceptions. Look backwards through list for insertion point.
2827 */
2828 list_for_each_entry_reverse(tmppf, pf_head, node) {
2829 if (tmppf->offset < pf->offset) {
2830 list_add(&pf->node, &tmppf->node);
2831 return 0;
2832 }
2833 }
2834 /*
2835 * if we get here, then the new offset is the lowest so
2836 * insert at the head
2837 */
2838 list_add(&pf->node, pf_head);
2839 return 0;
2840 }
2841
binder_translate_fd_array(struct list_head * pf_head,struct binder_fd_array_object * fda,const void __user * sender_ubuffer,struct binder_buffer_object * parent,struct binder_buffer_object * sender_uparent,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2842 static int binder_translate_fd_array(struct list_head *pf_head,
2843 struct binder_fd_array_object *fda,
2844 const void __user *sender_ubuffer,
2845 struct binder_buffer_object *parent,
2846 struct binder_buffer_object *sender_uparent,
2847 struct binder_transaction *t,
2848 struct binder_thread *thread,
2849 struct binder_transaction *in_reply_to)
2850 {
2851 binder_size_t fdi, fd_buf_size;
2852 binder_size_t fda_offset;
2853 const void __user *sender_ufda_base;
2854 struct binder_proc *proc = thread->proc;
2855 int ret;
2856
2857 if (fda->num_fds == 0)
2858 return 0;
2859
2860 fd_buf_size = sizeof(u32) * fda->num_fds;
2861 if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2862 binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n",
2863 proc->pid, thread->pid, (u64)fda->num_fds);
2864 return -EINVAL;
2865 }
2866 if (fd_buf_size > parent->length ||
2867 fda->parent_offset > parent->length - fd_buf_size) {
2868 /* No space for all file descriptors here. */
2869 binder_user_error("%d:%d not enough space to store %lld fds in buffer\n",
2870 proc->pid, thread->pid, (u64)fda->num_fds);
2871 return -EINVAL;
2872 }
2873 /*
2874 * the source data for binder_buffer_object is visible
2875 * to user-space and the @buffer element is the user
2876 * pointer to the buffer_object containing the fd_array.
2877 * Convert the address to an offset relative to
2878 * the base of the transaction buffer.
2879 */
2880 fda_offset = parent->buffer - t->buffer->user_data +
2881 fda->parent_offset;
2882 sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer +
2883 fda->parent_offset;
2884
2885 if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) ||
2886 !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) {
2887 binder_user_error("%d:%d parent offset not aligned correctly.\n",
2888 proc->pid, thread->pid);
2889 return -EINVAL;
2890 }
2891 ret = binder_add_fixup(pf_head, fda_offset, 0, fda->num_fds * sizeof(u32));
2892 if (ret)
2893 return ret;
2894
2895 for (fdi = 0; fdi < fda->num_fds; fdi++) {
2896 u32 fd;
2897 binder_size_t offset = fda_offset + fdi * sizeof(fd);
2898 binder_size_t sender_uoffset = fdi * sizeof(fd);
2899
2900 ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd));
2901 if (!ret)
2902 ret = binder_translate_fd(fd, offset, t, thread,
2903 in_reply_to);
2904 if (ret)
2905 return ret > 0 ? -EINVAL : ret;
2906 }
2907 return 0;
2908 }
2909
binder_fixup_parent(struct list_head * pf_head,struct binder_transaction * t,struct binder_thread * thread,struct binder_buffer_object * bp,binder_size_t off_start_offset,binder_size_t num_valid,binder_size_t last_fixup_obj_off,binder_size_t last_fixup_min_off)2910 static int binder_fixup_parent(struct list_head *pf_head,
2911 struct binder_transaction *t,
2912 struct binder_thread *thread,
2913 struct binder_buffer_object *bp,
2914 binder_size_t off_start_offset,
2915 binder_size_t num_valid,
2916 binder_size_t last_fixup_obj_off,
2917 binder_size_t last_fixup_min_off)
2918 {
2919 struct binder_buffer_object *parent;
2920 struct binder_buffer *b = t->buffer;
2921 struct binder_proc *proc = thread->proc;
2922 struct binder_proc *target_proc = t->to_proc;
2923 struct binder_object object;
2924 binder_size_t buffer_offset;
2925 binder_size_t parent_offset;
2926
2927 if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT))
2928 return 0;
2929
2930 parent = binder_validate_ptr(target_proc, b, &object, bp->parent,
2931 off_start_offset, &parent_offset,
2932 num_valid);
2933 if (!parent) {
2934 binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
2935 proc->pid, thread->pid);
2936 return -EINVAL;
2937 }
2938
2939 if (!binder_validate_fixup(target_proc, b, off_start_offset,
2940 parent_offset, bp->parent_offset,
2941 last_fixup_obj_off,
2942 last_fixup_min_off)) {
2943 binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
2944 proc->pid, thread->pid);
2945 return -EINVAL;
2946 }
2947
2948 if (parent->length < sizeof(binder_uintptr_t) ||
2949 bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) {
2950 /* No space for a pointer here! */
2951 binder_user_error("%d:%d got transaction with invalid parent offset\n",
2952 proc->pid, thread->pid);
2953 return -EINVAL;
2954 }
2955
2956 buffer_offset = bp->parent_offset + parent->buffer - b->user_data;
2957
2958 return binder_add_fixup(pf_head, buffer_offset, bp->buffer, 0);
2959 }
2960
2961 /**
2962 * binder_can_update_transaction() - Can a txn be superseded by an updated one?
2963 * @t1: the pending async txn in the frozen process
2964 * @t2: the new async txn to supersede the outdated pending one
2965 *
2966 * Return: true if t2 can supersede t1
2967 * false if t2 can not supersede t1
2968 */
binder_can_update_transaction(struct binder_transaction * t1,struct binder_transaction * t2)2969 static bool binder_can_update_transaction(struct binder_transaction *t1,
2970 struct binder_transaction *t2)
2971 {
2972 if ((t1->flags & t2->flags & (TF_ONE_WAY | TF_UPDATE_TXN)) !=
2973 (TF_ONE_WAY | TF_UPDATE_TXN) || !t1->to_proc || !t2->to_proc)
2974 return false;
2975 if (t1->to_proc->tsk == t2->to_proc->tsk && t1->code == t2->code &&
2976 t1->flags == t2->flags && t1->buffer->pid == t2->buffer->pid &&
2977 t1->buffer->target_node->ptr == t2->buffer->target_node->ptr &&
2978 t1->buffer->target_node->cookie == t2->buffer->target_node->cookie)
2979 return true;
2980 return false;
2981 }
2982
2983 /**
2984 * binder_find_outdated_transaction_ilocked() - Find the outdated transaction
2985 * @t: new async transaction
2986 * @target_list: list to find outdated transaction
2987 *
2988 * Return: the outdated transaction if found
2989 * NULL if no outdated transacton can be found
2990 *
2991 * Requires the proc->inner_lock to be held.
2992 */
2993 static struct binder_transaction *
binder_find_outdated_transaction_ilocked(struct binder_transaction * t,struct list_head * target_list)2994 binder_find_outdated_transaction_ilocked(struct binder_transaction *t,
2995 struct list_head *target_list)
2996 {
2997 struct binder_work *w;
2998
2999 list_for_each_entry(w, target_list, entry) {
3000 struct binder_transaction *t_queued;
3001
3002 if (w->type != BINDER_WORK_TRANSACTION)
3003 continue;
3004 t_queued = container_of(w, struct binder_transaction, work);
3005 if (binder_can_update_transaction(t_queued, t))
3006 return t_queued;
3007 }
3008 return NULL;
3009 }
3010
3011 /**
3012 * binder_proc_transaction() - sends a transaction to a process and wakes it up
3013 * @t: transaction to send
3014 * @proc: process to send the transaction to
3015 * @thread: thread in @proc to send the transaction to (may be NULL)
3016 *
3017 * This function queues a transaction to the specified process. It will try
3018 * to find a thread in the target process to handle the transaction and
3019 * wake it up. If no thread is found, the work is queued to the proc
3020 * waitqueue.
3021 *
3022 * If the @thread parameter is not NULL, the transaction is always queued
3023 * to the waitlist of that specific thread.
3024 *
3025 * Return: 0 if the transaction was successfully queued
3026 * BR_DEAD_REPLY if the target process or thread is dead
3027 * BR_FROZEN_REPLY if the target process or thread is frozen and
3028 * the sync transaction was rejected
3029 * BR_TRANSACTION_PENDING_FROZEN if the target process is frozen
3030 * and the async transaction was successfully queued
3031 */
binder_proc_transaction(struct binder_transaction * t,struct binder_proc * proc,struct binder_thread * thread)3032 static int binder_proc_transaction(struct binder_transaction *t,
3033 struct binder_proc *proc,
3034 struct binder_thread *thread)
3035 {
3036 struct binder_node *node = t->buffer->target_node;
3037 bool oneway = !!(t->flags & TF_ONE_WAY);
3038 bool pending_async = false;
3039 struct binder_transaction *t_outdated = NULL;
3040 bool frozen = false;
3041 bool enqueue_task = true;
3042
3043 BUG_ON(!node);
3044 binder_node_lock(node);
3045
3046 if (oneway) {
3047 BUG_ON(thread);
3048 if (node->has_async_transaction)
3049 pending_async = true;
3050 else
3051 node->has_async_transaction = true;
3052 }
3053
3054 binder_inner_proc_lock(proc);
3055 if (proc->is_frozen) {
3056 frozen = true;
3057 proc->sync_recv |= !oneway;
3058 proc->async_recv |= oneway;
3059 }
3060
3061 if ((frozen && !oneway) || proc->is_dead ||
3062 (thread && thread->is_dead)) {
3063 binder_inner_proc_unlock(proc);
3064 binder_node_unlock(node);
3065 return frozen ? BR_FROZEN_REPLY : BR_DEAD_REPLY;
3066 }
3067
3068 if (!thread && !pending_async)
3069 thread = binder_select_thread_ilocked(proc);
3070
3071 trace_android_vh_binder_proc_transaction(current, proc->tsk,
3072 thread ? thread->task : NULL, node->debug_id, t,
3073 pending_async);
3074
3075 if (thread) {
3076 binder_transaction_priority(thread, t, node);
3077 binder_enqueue_thread_work_ilocked(thread, &t->work);
3078 } else if (!pending_async) {
3079 trace_android_vh_binder_special_task(t, proc, thread,
3080 &t->work, &proc->todo, !oneway, &enqueue_task);
3081 if (enqueue_task)
3082 binder_enqueue_work_ilocked(&t->work, &proc->todo);
3083 } else {
3084 if ((t->flags & TF_UPDATE_TXN) && frozen) {
3085 t_outdated = binder_find_outdated_transaction_ilocked(t,
3086 &node->async_todo);
3087 if (t_outdated) {
3088 binder_debug(BINDER_DEBUG_TRANSACTION,
3089 "txn %d supersedes %d\n",
3090 t->debug_id, t_outdated->debug_id);
3091 list_del_init(&t_outdated->work.entry);
3092 proc->outstanding_txns--;
3093 }
3094 }
3095 trace_android_vh_binder_special_task(t, proc, thread,
3096 &t->work, &node->async_todo, !oneway, &enqueue_task);
3097 if (enqueue_task)
3098 binder_enqueue_work_ilocked(&t->work, &node->async_todo);
3099 }
3100
3101 trace_android_vh_binder_proc_transaction_finish(proc, t,
3102 thread ? thread->task : NULL, pending_async, !oneway);
3103 if (!pending_async)
3104 binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */);
3105
3106 proc->outstanding_txns++;
3107 binder_inner_proc_unlock(proc);
3108 binder_node_unlock(node);
3109
3110 /*
3111 * To reduce potential contention, free the outdated transaction and
3112 * buffer after releasing the locks.
3113 */
3114 if (t_outdated) {
3115 struct binder_buffer *buffer = t_outdated->buffer;
3116
3117 t_outdated->buffer = NULL;
3118 buffer->transaction = NULL;
3119 trace_binder_transaction_update_buffer_release(buffer);
3120 binder_release_entire_buffer(proc, NULL, buffer, false);
3121 binder_alloc_free_buf(&proc->alloc, buffer);
3122 kfree(t_outdated);
3123 binder_stats_deleted(BINDER_STAT_TRANSACTION);
3124 }
3125
3126 if (oneway && frozen)
3127 return BR_TRANSACTION_PENDING_FROZEN;
3128
3129 return 0;
3130 }
3131
3132 /**
3133 * binder_get_node_refs_for_txn() - Get required refs on node for txn
3134 * @node: struct binder_node for which to get refs
3135 * @procp: returns @node->proc if valid
3136 * @error: if no @procp then returns BR_DEAD_REPLY
3137 *
3138 * User-space normally keeps the node alive when creating a transaction
3139 * since it has a reference to the target. The local strong ref keeps it
3140 * alive if the sending process dies before the target process processes
3141 * the transaction. If the source process is malicious or has a reference
3142 * counting bug, relying on the local strong ref can fail.
3143 *
3144 * Since user-space can cause the local strong ref to go away, we also take
3145 * a tmpref on the node to ensure it survives while we are constructing
3146 * the transaction. We also need a tmpref on the proc while we are
3147 * constructing the transaction, so we take that here as well.
3148 *
3149 * Return: The target_node with refs taken or NULL if no @node->proc is NULL.
3150 * Also sets @procp if valid. If the @node->proc is NULL indicating that the
3151 * target proc has died, @error is set to BR_DEAD_REPLY.
3152 */
binder_get_node_refs_for_txn(struct binder_node * node,struct binder_proc ** procp,uint32_t * error)3153 static struct binder_node *binder_get_node_refs_for_txn(
3154 struct binder_node *node,
3155 struct binder_proc **procp,
3156 uint32_t *error)
3157 {
3158 struct binder_node *target_node = NULL;
3159
3160 binder_node_inner_lock(node);
3161 if (node->proc) {
3162 target_node = node;
3163 binder_inc_node_nilocked(node, 1, 0, NULL);
3164 binder_inc_node_tmpref_ilocked(node);
3165 node->proc->tmp_ref++;
3166 *procp = node->proc;
3167 } else
3168 *error = BR_DEAD_REPLY;
3169 binder_node_inner_unlock(node);
3170
3171 return target_node;
3172 }
3173
binder_set_txn_from_error(struct binder_transaction * t,int id,uint32_t command,int32_t param)3174 static void binder_set_txn_from_error(struct binder_transaction *t, int id,
3175 uint32_t command, int32_t param)
3176 {
3177 struct binder_thread *from = binder_get_txn_from_and_acq_inner(t);
3178
3179 if (!from) {
3180 /* annotation for sparse */
3181 __release(&from->proc->inner_lock);
3182 return;
3183 }
3184
3185 /* don't override existing errors */
3186 if (from->ee.command == BR_OK)
3187 binder_set_extended_error(&from->ee, id, command, param);
3188 binder_inner_proc_unlock(from->proc);
3189 binder_thread_dec_tmpref(from);
3190 }
3191
3192 /**
3193 * binder_netlink_report() - report a transaction failure via netlink
3194 * @proc: the binder proc sending the transaction
3195 * @t: the binder transaction that failed
3196 * @data_size: the user provided data size for the transaction
3197 * @error: enum binder_driver_return_protocol returned to sender
3198 * @reply: whether the transaction is a reply
3199 */
binder_netlink_report(struct binder_proc * proc,struct binder_transaction * t,u32 data_size,u32 error,int is_reply)3200 static void binder_netlink_report(struct binder_proc *proc,
3201 struct binder_transaction *t,
3202 u32 data_size,
3203 u32 error,
3204 int is_reply)
3205 {
3206 const char *context = proc->context->name;
3207 struct sk_buff *skb;
3208 void *hdr;
3209
3210 if (!genl_has_listeners(&binder_nl_family, &init_net,
3211 BINDER_NLGRP_REPORT))
3212 return;
3213
3214 trace_binder_netlink_report(context, t, data_size, error, is_reply);
3215
3216 skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
3217 if (!skb)
3218 return;
3219
3220 hdr = genlmsg_put(skb, 0, 0, &binder_nl_family, 0, BINDER_CMD_REPORT);
3221 if (!hdr)
3222 goto free_skb;
3223
3224 if (nla_put_u32(skb, BINDER_A_REPORT_ERROR, error) ||
3225 nla_put_string(skb, BINDER_A_REPORT_CONTEXT, context) ||
3226 nla_put_u32(skb, BINDER_A_REPORT_FROM_PID, t->from_pid) ||
3227 nla_put_u32(skb, BINDER_A_REPORT_FROM_TID, t->from_tid))
3228 goto cancel_skb;
3229
3230 if (t->to_proc &&
3231 nla_put_u32(skb, BINDER_A_REPORT_TO_PID, t->to_proc->pid))
3232 goto cancel_skb;
3233
3234 if (t->to_thread &&
3235 nla_put_u32(skb, BINDER_A_REPORT_TO_TID, t->to_thread->pid))
3236 goto cancel_skb;
3237
3238 if (is_reply && nla_put_flag(skb, BINDER_A_REPORT_IS_REPLY))
3239 goto cancel_skb;
3240
3241 if (nla_put_u32(skb, BINDER_A_REPORT_FLAGS, t->flags) ||
3242 nla_put_u32(skb, BINDER_A_REPORT_CODE, t->code) ||
3243 nla_put_u32(skb, BINDER_A_REPORT_DATA_SIZE, data_size))
3244 goto cancel_skb;
3245
3246 genlmsg_end(skb, hdr);
3247 genlmsg_multicast(&binder_nl_family, skb, 0, BINDER_NLGRP_REPORT,
3248 GFP_KERNEL);
3249 return;
3250
3251 cancel_skb:
3252 genlmsg_cancel(skb, hdr);
3253 free_skb:
3254 nlmsg_free(skb);
3255 }
3256
binder_transaction(struct binder_proc * proc,struct binder_thread * thread,struct binder_transaction_data * tr,int reply,binder_size_t extra_buffers_size)3257 static void binder_transaction(struct binder_proc *proc,
3258 struct binder_thread *thread,
3259 struct binder_transaction_data *tr, int reply,
3260 binder_size_t extra_buffers_size)
3261 {
3262 int ret;
3263 struct binder_transaction *t;
3264 struct binder_work *w;
3265 struct binder_work *tcomplete;
3266 binder_size_t buffer_offset = 0;
3267 binder_size_t off_start_offset, off_end_offset;
3268 binder_size_t off_min;
3269 binder_size_t sg_buf_offset, sg_buf_end_offset;
3270 binder_size_t user_offset = 0;
3271 struct binder_proc *target_proc = NULL;
3272 struct binder_thread *target_thread = NULL;
3273 struct binder_node *target_node = NULL;
3274 struct binder_transaction *in_reply_to = NULL;
3275 struct binder_transaction_log_entry *e;
3276 uint32_t return_error = 0;
3277 uint32_t return_error_param = 0;
3278 uint32_t return_error_line = 0;
3279 binder_size_t last_fixup_obj_off = 0;
3280 binder_size_t last_fixup_min_off = 0;
3281 struct binder_context *context = proc->context;
3282 int t_debug_id = atomic_inc_return(&binder_last_id);
3283 ktime_t t_start_time = ktime_get();
3284 char *secctx = NULL;
3285 u32 secctx_sz = 0;
3286 struct list_head sgc_head;
3287 struct list_head pf_head;
3288 const void __user *user_buffer = (const void __user *)
3289 (uintptr_t)tr->data.ptr.buffer;
3290 bool is_nested = false;
3291 INIT_LIST_HEAD(&sgc_head);
3292 INIT_LIST_HEAD(&pf_head);
3293
3294 e = binder_transaction_log_add(&binder_transaction_log);
3295 e->debug_id = t_debug_id;
3296 e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
3297 e->from_proc = proc->pid;
3298 e->from_thread = thread->pid;
3299 e->target_handle = tr->target.handle;
3300 e->data_size = tr->data_size;
3301 e->offsets_size = tr->offsets_size;
3302 strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME);
3303
3304 binder_inner_proc_lock(proc);
3305 binder_set_extended_error(&thread->ee, t_debug_id, BR_OK, 0);
3306 binder_inner_proc_unlock(proc);
3307
3308 t = kzalloc(sizeof(*t), GFP_KERNEL);
3309 if (!t) {
3310 binder_txn_error("%d:%d cannot allocate transaction\n",
3311 thread->pid, proc->pid);
3312 return_error = BR_FAILED_REPLY;
3313 return_error_param = -ENOMEM;
3314 return_error_line = __LINE__;
3315 goto err_alloc_t_failed;
3316 }
3317 INIT_LIST_HEAD(&t->fd_fixups);
3318 binder_stats_created(BINDER_STAT_TRANSACTION);
3319 spin_lock_init(&t->lock);
3320 t->debug_id = t_debug_id;
3321 t->start_time = t_start_time;
3322 t->from_pid = proc->pid;
3323 t->from_tid = thread->pid;
3324 t->sender_euid = task_euid(proc->tsk);
3325 t->code = tr->code;
3326 t->flags = tr->flags;
3327 t->work.type = BINDER_WORK_TRANSACTION;
3328 if (!reply && !(tr->flags & TF_ONE_WAY))
3329 t->from = thread;
3330
3331 if (reply) {
3332 binder_inner_proc_lock(proc);
3333 in_reply_to = thread->transaction_stack;
3334 if (in_reply_to == NULL) {
3335 binder_inner_proc_unlock(proc);
3336 binder_user_error("%d:%d got reply transaction with no transaction stack\n",
3337 proc->pid, thread->pid);
3338 return_error = BR_FAILED_REPLY;
3339 return_error_param = -EPROTO;
3340 return_error_line = __LINE__;
3341 goto err_empty_call_stack;
3342 }
3343 if (in_reply_to->to_thread != thread) {
3344 spin_lock(&in_reply_to->lock);
3345 binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n",
3346 proc->pid, thread->pid, in_reply_to->debug_id,
3347 in_reply_to->to_proc ?
3348 in_reply_to->to_proc->pid : 0,
3349 in_reply_to->to_thread ?
3350 in_reply_to->to_thread->pid : 0);
3351 spin_unlock(&in_reply_to->lock);
3352 binder_inner_proc_unlock(proc);
3353 return_error = BR_FAILED_REPLY;
3354 return_error_param = -EPROTO;
3355 return_error_line = __LINE__;
3356 in_reply_to = NULL;
3357 goto err_bad_call_stack;
3358 }
3359 thread->transaction_stack = in_reply_to->to_parent;
3360 binder_inner_proc_unlock(proc);
3361 target_thread = binder_get_txn_from_and_acq_inner(in_reply_to);
3362 if (target_thread == NULL) {
3363 /* annotation for sparse */
3364 __release(&target_thread->proc->inner_lock);
3365 binder_txn_error("%d:%d reply target not found\n",
3366 thread->pid, proc->pid);
3367 return_error = BR_DEAD_REPLY;
3368 return_error_line = __LINE__;
3369 goto err_dead_binder;
3370 }
3371 if (target_thread->transaction_stack != in_reply_to) {
3372 binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n",
3373 proc->pid, thread->pid,
3374 target_thread->transaction_stack ?
3375 target_thread->transaction_stack->debug_id : 0,
3376 in_reply_to->debug_id);
3377 binder_inner_proc_unlock(target_thread->proc);
3378 return_error = BR_FAILED_REPLY;
3379 return_error_param = -EPROTO;
3380 return_error_line = __LINE__;
3381 in_reply_to = NULL;
3382 target_thread = NULL;
3383 goto err_dead_binder;
3384 }
3385 target_proc = target_thread->proc;
3386 target_proc->tmp_ref++;
3387 binder_inner_proc_unlock(target_thread->proc);
3388 trace_android_vh_binder_reply(target_proc, proc, thread, tr);
3389 } else {
3390 if (tr->target.handle) {
3391 struct binder_ref *ref;
3392
3393 /*
3394 * There must already be a strong ref
3395 * on this node. If so, do a strong
3396 * increment on the node to ensure it
3397 * stays alive until the transaction is
3398 * done.
3399 */
3400 binder_proc_lock(proc);
3401 ref = binder_get_ref_olocked(proc, tr->target.handle,
3402 true);
3403 if (ref) {
3404 target_node = binder_get_node_refs_for_txn(
3405 ref->node, &target_proc,
3406 &return_error);
3407 } else {
3408 binder_user_error("%d:%d got transaction to invalid handle, %u\n",
3409 proc->pid, thread->pid, tr->target.handle);
3410 return_error = BR_FAILED_REPLY;
3411 }
3412 binder_proc_unlock(proc);
3413 } else {
3414 mutex_lock(&context->context_mgr_node_lock);
3415 target_node = context->binder_context_mgr_node;
3416 if (target_node)
3417 target_node = binder_get_node_refs_for_txn(
3418 target_node, &target_proc,
3419 &return_error);
3420 else
3421 return_error = BR_DEAD_REPLY;
3422 mutex_unlock(&context->context_mgr_node_lock);
3423 if (target_node && target_proc->pid == proc->pid) {
3424 binder_user_error("%d:%d got transaction to context manager from process owning it\n",
3425 proc->pid, thread->pid);
3426 return_error = BR_FAILED_REPLY;
3427 return_error_param = -EINVAL;
3428 return_error_line = __LINE__;
3429 goto err_invalid_target_handle;
3430 }
3431 }
3432 if (!target_node) {
3433 binder_txn_error("%d:%d cannot find target node\n",
3434 thread->pid, proc->pid);
3435 /*
3436 * return_error is set above
3437 */
3438 return_error_param = -EINVAL;
3439 return_error_line = __LINE__;
3440 goto err_dead_binder;
3441 }
3442 e->to_node = target_node->debug_id;
3443 if (WARN_ON(proc == target_proc)) {
3444 binder_txn_error("%d:%d self transactions not allowed\n",
3445 thread->pid, proc->pid);
3446 return_error = BR_FAILED_REPLY;
3447 return_error_param = -EINVAL;
3448 return_error_line = __LINE__;
3449 goto err_invalid_target_handle;
3450 }
3451 trace_android_vh_binder_trans(target_proc, proc, thread, tr);
3452 if (security_binder_transaction(proc->cred,
3453 target_proc->cred) < 0) {
3454 binder_txn_error("%d:%d transaction credentials failed\n",
3455 thread->pid, proc->pid);
3456 return_error = BR_FAILED_REPLY;
3457 return_error_param = -EPERM;
3458 return_error_line = __LINE__;
3459 goto err_invalid_target_handle;
3460 }
3461 binder_inner_proc_lock(proc);
3462
3463 w = list_first_entry_or_null(&thread->todo,
3464 struct binder_work, entry);
3465 if (!(tr->flags & TF_ONE_WAY) && w &&
3466 w->type == BINDER_WORK_TRANSACTION) {
3467 /*
3468 * Do not allow new outgoing transaction from a
3469 * thread that has a transaction at the head of
3470 * its todo list. Only need to check the head
3471 * because binder_select_thread_ilocked picks a
3472 * thread from proc->waiting_threads to enqueue
3473 * the transaction, and nothing is queued to the
3474 * todo list while the thread is on waiting_threads.
3475 */
3476 binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n",
3477 proc->pid, thread->pid);
3478 binder_inner_proc_unlock(proc);
3479 return_error = BR_FAILED_REPLY;
3480 return_error_param = -EPROTO;
3481 return_error_line = __LINE__;
3482 goto err_bad_todo_list;
3483 }
3484
3485 if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
3486 struct binder_transaction *tmp;
3487
3488 tmp = thread->transaction_stack;
3489 if (tmp->to_thread != thread) {
3490 spin_lock(&tmp->lock);
3491 binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n",
3492 proc->pid, thread->pid, tmp->debug_id,
3493 tmp->to_proc ? tmp->to_proc->pid : 0,
3494 tmp->to_thread ?
3495 tmp->to_thread->pid : 0);
3496 spin_unlock(&tmp->lock);
3497 binder_inner_proc_unlock(proc);
3498 return_error = BR_FAILED_REPLY;
3499 return_error_param = -EPROTO;
3500 return_error_line = __LINE__;
3501 goto err_bad_call_stack;
3502 }
3503 while (tmp) {
3504 struct binder_thread *from;
3505
3506 spin_lock(&tmp->lock);
3507 from = tmp->from;
3508 if (from && from->proc == target_proc) {
3509 atomic_inc(&from->tmp_ref);
3510 target_thread = from;
3511 spin_unlock(&tmp->lock);
3512 is_nested = true;
3513 break;
3514 }
3515 spin_unlock(&tmp->lock);
3516 tmp = tmp->from_parent;
3517 }
3518 }
3519 binder_inner_proc_unlock(proc);
3520 }
3521
3522 t->to_proc = target_proc;
3523 t->to_thread = target_thread;
3524 if (target_thread)
3525 e->to_thread = target_thread->pid;
3526 e->to_proc = target_proc->pid;
3527
3528 trace_android_vh_binder_transaction_init(t);
3529
3530 tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
3531 if (tcomplete == NULL) {
3532 binder_txn_error("%d:%d cannot allocate work for transaction\n",
3533 thread->pid, proc->pid);
3534 return_error = BR_FAILED_REPLY;
3535 return_error_param = -ENOMEM;
3536 return_error_line = __LINE__;
3537 goto err_alloc_tcomplete_failed;
3538 }
3539 binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE);
3540
3541 if (reply)
3542 binder_debug(BINDER_DEBUG_TRANSACTION,
3543 "%d:%d BC_REPLY %d -> %d:%d, data %016llx-%016llx size %lld-%lld-%lld\n",
3544 proc->pid, thread->pid, t->debug_id,
3545 target_proc->pid, target_thread->pid,
3546 (u64)tr->data.ptr.buffer,
3547 (u64)tr->data.ptr.offsets,
3548 (u64)tr->data_size, (u64)tr->offsets_size,
3549 (u64)extra_buffers_size);
3550 else
3551 binder_debug(BINDER_DEBUG_TRANSACTION,
3552 "%d:%d BC_TRANSACTION %d -> %d - node %d, data %016llx-%016llx size %lld-%lld-%lld\n",
3553 proc->pid, thread->pid, t->debug_id,
3554 target_proc->pid, target_node->debug_id,
3555 (u64)tr->data.ptr.buffer,
3556 (u64)tr->data.ptr.offsets,
3557 (u64)tr->data_size, (u64)tr->offsets_size,
3558 (u64)extra_buffers_size);
3559
3560 t->is_nested = is_nested;
3561 if (!(t->flags & TF_ONE_WAY) &&
3562 binder_supported_policy(current->policy)) {
3563 /* Inherit supported policies for synchronous transactions */
3564 t->priority.sched_policy = current->policy;
3565 t->priority.prio = current->normal_prio;
3566 } else {
3567 /* Otherwise, fall back to the default priority */
3568 t->priority = target_proc->default_priority;
3569 }
3570
3571 if (target_node && target_node->txn_security_ctx) {
3572 u32 secid;
3573 size_t added_size;
3574
3575 security_cred_getsecid(proc->cred, &secid);
3576 ret = security_secid_to_secctx(secid, &secctx, &secctx_sz);
3577 if (ret) {
3578 binder_txn_error("%d:%d failed to get security context\n",
3579 thread->pid, proc->pid);
3580 return_error = BR_FAILED_REPLY;
3581 return_error_param = ret;
3582 return_error_line = __LINE__;
3583 goto err_get_secctx_failed;
3584 }
3585 added_size = ALIGN(secctx_sz, sizeof(u64));
3586 extra_buffers_size += added_size;
3587 if (extra_buffers_size < added_size) {
3588 binder_txn_error("%d:%d integer overflow of extra_buffers_size\n",
3589 thread->pid, proc->pid);
3590 return_error = BR_FAILED_REPLY;
3591 return_error_param = -EINVAL;
3592 return_error_line = __LINE__;
3593 goto err_bad_extra_size;
3594 }
3595 }
3596
3597 trace_binder_transaction(reply, t, target_node);
3598
3599 t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
3600 tr->offsets_size, extra_buffers_size,
3601 !reply && (t->flags & TF_ONE_WAY));
3602 if (IS_ERR(t->buffer)) {
3603 char *s;
3604
3605 ret = PTR_ERR(t->buffer);
3606 s = (ret == -ESRCH) ? ": vma cleared, target dead or dying"
3607 : (ret == -ENOSPC) ? ": no space left"
3608 : (ret == -ENOMEM) ? ": memory allocation failed"
3609 : "";
3610 binder_txn_error("cannot allocate buffer%s", s);
3611
3612 return_error_param = PTR_ERR(t->buffer);
3613 return_error = return_error_param == -ESRCH ?
3614 BR_DEAD_REPLY : BR_FAILED_REPLY;
3615 return_error_line = __LINE__;
3616 t->buffer = NULL;
3617 goto err_binder_alloc_buf_failed;
3618 }
3619 if (secctx) {
3620 int err;
3621 size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
3622 ALIGN(tr->offsets_size, sizeof(void *)) +
3623 ALIGN(extra_buffers_size, sizeof(void *)) -
3624 ALIGN(secctx_sz, sizeof(u64));
3625
3626 t->security_ctx = t->buffer->user_data + buf_offset;
3627 err = binder_alloc_copy_to_buffer(&target_proc->alloc,
3628 t->buffer, buf_offset,
3629 secctx, secctx_sz);
3630 if (err) {
3631 t->security_ctx = 0;
3632 WARN_ON(1);
3633 }
3634 security_release_secctx(secctx, secctx_sz);
3635 secctx = NULL;
3636 }
3637 t->buffer->debug_id = t->debug_id;
3638 t->buffer->transaction = t;
3639 t->buffer->target_node = target_node;
3640 t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF);
3641 trace_binder_transaction_alloc_buf(t->buffer);
3642 trace_android_vh_alloc_oem_binder_struct(tr, t, target_proc);
3643
3644 if (binder_alloc_copy_user_to_buffer(
3645 &target_proc->alloc,
3646 t->buffer,
3647 ALIGN(tr->data_size, sizeof(void *)),
3648 (const void __user *)
3649 (uintptr_t)tr->data.ptr.offsets,
3650 tr->offsets_size)) {
3651 binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3652 proc->pid, thread->pid);
3653 return_error = BR_FAILED_REPLY;
3654 return_error_param = -EFAULT;
3655 return_error_line = __LINE__;
3656 goto err_copy_data_failed;
3657 }
3658 if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) {
3659 binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n",
3660 proc->pid, thread->pid, (u64)tr->offsets_size);
3661 return_error = BR_FAILED_REPLY;
3662 return_error_param = -EINVAL;
3663 return_error_line = __LINE__;
3664 goto err_bad_offset;
3665 }
3666 if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) {
3667 binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
3668 proc->pid, thread->pid,
3669 (u64)extra_buffers_size);
3670 return_error = BR_FAILED_REPLY;
3671 return_error_param = -EINVAL;
3672 return_error_line = __LINE__;
3673 goto err_bad_offset;
3674 }
3675 off_start_offset = ALIGN(tr->data_size, sizeof(void *));
3676 buffer_offset = off_start_offset;
3677 off_end_offset = off_start_offset + tr->offsets_size;
3678 sg_buf_offset = ALIGN(off_end_offset, sizeof(void *));
3679 sg_buf_end_offset = sg_buf_offset + extra_buffers_size -
3680 ALIGN(secctx_sz, sizeof(u64));
3681 off_min = 0;
3682 for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
3683 buffer_offset += sizeof(binder_size_t)) {
3684 struct binder_object_header *hdr;
3685 size_t object_size;
3686 struct binder_object object;
3687 binder_size_t object_offset;
3688 binder_size_t copy_size;
3689
3690 if (binder_alloc_copy_from_buffer(&target_proc->alloc,
3691 &object_offset,
3692 t->buffer,
3693 buffer_offset,
3694 sizeof(object_offset))) {
3695 binder_txn_error("%d:%d copy offset from buffer failed\n",
3696 thread->pid, proc->pid);
3697 return_error = BR_FAILED_REPLY;
3698 return_error_param = -EINVAL;
3699 return_error_line = __LINE__;
3700 goto err_bad_offset;
3701 }
3702
3703 /*
3704 * Copy the source user buffer up to the next object
3705 * that will be processed.
3706 */
3707 copy_size = object_offset - user_offset;
3708 if (copy_size && (user_offset > object_offset ||
3709 object_offset > tr->data_size ||
3710 binder_alloc_copy_user_to_buffer(
3711 &target_proc->alloc,
3712 t->buffer, user_offset,
3713 user_buffer + user_offset,
3714 copy_size))) {
3715 binder_user_error("%d:%d got transaction with invalid data ptr\n",
3716 proc->pid, thread->pid);
3717 return_error = BR_FAILED_REPLY;
3718 return_error_param = -EFAULT;
3719 return_error_line = __LINE__;
3720 goto err_copy_data_failed;
3721 }
3722 object_size = binder_get_object(target_proc, user_buffer,
3723 t->buffer, object_offset, &object);
3724 if (object_size == 0 || object_offset < off_min) {
3725 binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n",
3726 proc->pid, thread->pid,
3727 (u64)object_offset,
3728 (u64)off_min,
3729 (u64)t->buffer->data_size);
3730 return_error = BR_FAILED_REPLY;
3731 return_error_param = -EINVAL;
3732 return_error_line = __LINE__;
3733 goto err_bad_offset;
3734 }
3735 /*
3736 * Set offset to the next buffer fragment to be
3737 * copied
3738 */
3739 user_offset = object_offset + object_size;
3740
3741 hdr = &object.hdr;
3742 off_min = object_offset + object_size;
3743 switch (hdr->type) {
3744 case BINDER_TYPE_BINDER:
3745 case BINDER_TYPE_WEAK_BINDER: {
3746 struct flat_binder_object *fp;
3747
3748 fp = to_flat_binder_object(hdr);
3749 ret = binder_translate_binder(fp, t, thread);
3750
3751 if (ret < 0 ||
3752 binder_alloc_copy_to_buffer(&target_proc->alloc,
3753 t->buffer,
3754 object_offset,
3755 fp, sizeof(*fp))) {
3756 binder_txn_error("%d:%d translate binder failed\n",
3757 thread->pid, proc->pid);
3758 return_error = BR_FAILED_REPLY;
3759 return_error_param = ret;
3760 return_error_line = __LINE__;
3761 goto err_translate_failed;
3762 }
3763 } break;
3764 case BINDER_TYPE_HANDLE:
3765 case BINDER_TYPE_WEAK_HANDLE: {
3766 struct flat_binder_object *fp;
3767
3768 fp = to_flat_binder_object(hdr);
3769 ret = binder_translate_handle(fp, t, thread);
3770 if (ret < 0 ||
3771 binder_alloc_copy_to_buffer(&target_proc->alloc,
3772 t->buffer,
3773 object_offset,
3774 fp, sizeof(*fp))) {
3775 binder_txn_error("%d:%d translate handle failed\n",
3776 thread->pid, proc->pid);
3777 return_error = BR_FAILED_REPLY;
3778 return_error_param = ret;
3779 return_error_line = __LINE__;
3780 goto err_translate_failed;
3781 }
3782 } break;
3783
3784 case BINDER_TYPE_FD: {
3785 struct binder_fd_object *fp = to_binder_fd_object(hdr);
3786 binder_size_t fd_offset = object_offset +
3787 (uintptr_t)&fp->fd - (uintptr_t)fp;
3788 int ret = binder_translate_fd(fp->fd, fd_offset, t,
3789 thread, in_reply_to);
3790
3791 fp->pad_binder = 0;
3792 if (ret < 0 ||
3793 binder_alloc_copy_to_buffer(&target_proc->alloc,
3794 t->buffer,
3795 object_offset,
3796 fp, sizeof(*fp))) {
3797 binder_txn_error("%d:%d translate fd failed\n",
3798 thread->pid, proc->pid);
3799 return_error = BR_FAILED_REPLY;
3800 return_error_param = ret;
3801 return_error_line = __LINE__;
3802 goto err_translate_failed;
3803 }
3804 } break;
3805 case BINDER_TYPE_FDA: {
3806 struct binder_object ptr_object;
3807 binder_size_t parent_offset;
3808 struct binder_object user_object;
3809 size_t user_parent_size;
3810 struct binder_fd_array_object *fda =
3811 to_binder_fd_array_object(hdr);
3812 size_t num_valid = (buffer_offset - off_start_offset) /
3813 sizeof(binder_size_t);
3814 struct binder_buffer_object *parent =
3815 binder_validate_ptr(target_proc, t->buffer,
3816 &ptr_object, fda->parent,
3817 off_start_offset,
3818 &parent_offset,
3819 num_valid);
3820 if (!parent) {
3821 binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
3822 proc->pid, thread->pid);
3823 return_error = BR_FAILED_REPLY;
3824 return_error_param = -EINVAL;
3825 return_error_line = __LINE__;
3826 goto err_bad_parent;
3827 }
3828 if (!binder_validate_fixup(target_proc, t->buffer,
3829 off_start_offset,
3830 parent_offset,
3831 fda->parent_offset,
3832 last_fixup_obj_off,
3833 last_fixup_min_off)) {
3834 binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
3835 proc->pid, thread->pid);
3836 return_error = BR_FAILED_REPLY;
3837 return_error_param = -EINVAL;
3838 return_error_line = __LINE__;
3839 goto err_bad_parent;
3840 }
3841 /*
3842 * We need to read the user version of the parent
3843 * object to get the original user offset
3844 */
3845 user_parent_size =
3846 binder_get_object(proc, user_buffer, t->buffer,
3847 parent_offset, &user_object);
3848 if (user_parent_size != sizeof(user_object.bbo)) {
3849 binder_user_error("%d:%d invalid ptr object size: %zd vs %zd\n",
3850 proc->pid, thread->pid,
3851 user_parent_size,
3852 sizeof(user_object.bbo));
3853 return_error = BR_FAILED_REPLY;
3854 return_error_param = -EINVAL;
3855 return_error_line = __LINE__;
3856 goto err_bad_parent;
3857 }
3858 ret = binder_translate_fd_array(&pf_head, fda,
3859 user_buffer, parent,
3860 &user_object.bbo, t,
3861 thread, in_reply_to);
3862 if (!ret)
3863 ret = binder_alloc_copy_to_buffer(&target_proc->alloc,
3864 t->buffer,
3865 object_offset,
3866 fda, sizeof(*fda));
3867 if (ret) {
3868 binder_txn_error("%d:%d translate fd array failed\n",
3869 thread->pid, proc->pid);
3870 return_error = BR_FAILED_REPLY;
3871 return_error_param = ret > 0 ? -EINVAL : ret;
3872 return_error_line = __LINE__;
3873 goto err_translate_failed;
3874 }
3875 last_fixup_obj_off = parent_offset;
3876 last_fixup_min_off =
3877 fda->parent_offset + sizeof(u32) * fda->num_fds;
3878 } break;
3879 case BINDER_TYPE_PTR: {
3880 struct binder_buffer_object *bp =
3881 to_binder_buffer_object(hdr);
3882 size_t buf_left = sg_buf_end_offset - sg_buf_offset;
3883 size_t num_valid;
3884
3885 if (bp->length > buf_left) {
3886 binder_user_error("%d:%d got transaction with too large buffer\n",
3887 proc->pid, thread->pid);
3888 return_error = BR_FAILED_REPLY;
3889 return_error_param = -EINVAL;
3890 return_error_line = __LINE__;
3891 goto err_bad_offset;
3892 }
3893 ret = binder_defer_copy(&sgc_head, sg_buf_offset,
3894 (const void __user *)(uintptr_t)bp->buffer,
3895 bp->length);
3896 if (ret) {
3897 binder_txn_error("%d:%d deferred copy failed\n",
3898 thread->pid, proc->pid);
3899 return_error = BR_FAILED_REPLY;
3900 return_error_param = ret;
3901 return_error_line = __LINE__;
3902 goto err_translate_failed;
3903 }
3904 /* Fixup buffer pointer to target proc address space */
3905 bp->buffer = t->buffer->user_data + sg_buf_offset;
3906 sg_buf_offset += ALIGN(bp->length, sizeof(u64));
3907
3908 num_valid = (buffer_offset - off_start_offset) /
3909 sizeof(binder_size_t);
3910 ret = binder_fixup_parent(&pf_head, t,
3911 thread, bp,
3912 off_start_offset,
3913 num_valid,
3914 last_fixup_obj_off,
3915 last_fixup_min_off);
3916 if (ret < 0 ||
3917 binder_alloc_copy_to_buffer(&target_proc->alloc,
3918 t->buffer,
3919 object_offset,
3920 bp, sizeof(*bp))) {
3921 binder_txn_error("%d:%d failed to fixup parent\n",
3922 thread->pid, proc->pid);
3923 return_error = BR_FAILED_REPLY;
3924 return_error_param = ret;
3925 return_error_line = __LINE__;
3926 goto err_translate_failed;
3927 }
3928 last_fixup_obj_off = object_offset;
3929 last_fixup_min_off = 0;
3930 } break;
3931 default:
3932 binder_user_error("%d:%d got transaction with invalid object type, %x\n",
3933 proc->pid, thread->pid, hdr->type);
3934 return_error = BR_FAILED_REPLY;
3935 return_error_param = -EINVAL;
3936 return_error_line = __LINE__;
3937 goto err_bad_object_type;
3938 }
3939 }
3940 /* Done processing objects, copy the rest of the buffer */
3941 if (binder_alloc_copy_user_to_buffer(
3942 &target_proc->alloc,
3943 t->buffer, user_offset,
3944 user_buffer + user_offset,
3945 tr->data_size - user_offset)) {
3946 binder_user_error("%d:%d got transaction with invalid data ptr\n",
3947 proc->pid, thread->pid);
3948 return_error = BR_FAILED_REPLY;
3949 return_error_param = -EFAULT;
3950 return_error_line = __LINE__;
3951 goto err_copy_data_failed;
3952 }
3953
3954 ret = binder_do_deferred_txn_copies(&target_proc->alloc, t->buffer,
3955 &sgc_head, &pf_head);
3956 if (ret) {
3957 binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3958 proc->pid, thread->pid);
3959 return_error = BR_FAILED_REPLY;
3960 return_error_param = ret;
3961 return_error_line = __LINE__;
3962 goto err_copy_data_failed;
3963 }
3964 if (t->buffer->oneway_spam_suspect) {
3965 tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT;
3966 binder_netlink_report(proc, t, tr->data_size,
3967 BR_ONEWAY_SPAM_SUSPECT, reply);
3968 } else {
3969 tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
3970 }
3971
3972 trace_android_vh_binder_transaction_record(tr, t, in_reply_to);
3973
3974 if (reply) {
3975 binder_enqueue_thread_work(thread, tcomplete);
3976 binder_inner_proc_lock(target_proc);
3977 if (target_thread->is_dead) {
3978 return_error = BR_DEAD_REPLY;
3979 binder_inner_proc_unlock(target_proc);
3980 goto err_dead_proc_or_thread;
3981 }
3982 BUG_ON(t->buffer->async_transaction != 0);
3983 binder_pop_transaction_ilocked(target_thread, in_reply_to);
3984 binder_enqueue_thread_work_ilocked(target_thread, &t->work);
3985 target_proc->outstanding_txns++;
3986 binder_inner_proc_unlock(target_proc);
3987 if (in_reply_to->is_nested) {
3988 spin_lock(&thread->prio_lock);
3989 thread->prio_state = BINDER_PRIO_PENDING;
3990 thread->prio_next = in_reply_to->saved_priority;
3991 spin_unlock(&thread->prio_lock);
3992 }
3993 wake_up_interruptible_sync(&target_thread->wait);
3994 trace_android_vh_binder_restore_priority(in_reply_to, current);
3995 binder_restore_priority(thread, &in_reply_to->saved_priority);
3996 binder_free_transaction(in_reply_to);
3997 } else if (!(t->flags & TF_ONE_WAY)) {
3998 BUG_ON(t->buffer->async_transaction != 0);
3999 binder_inner_proc_lock(proc);
4000 /*
4001 * Defer the TRANSACTION_COMPLETE, so we don't return to
4002 * userspace immediately; this allows the target process to
4003 * immediately start processing this transaction, reducing
4004 * latency. We will then return the TRANSACTION_COMPLETE when
4005 * the target replies (or there is an error).
4006 */
4007 binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete);
4008 t->need_reply = 1;
4009 t->from_parent = thread->transaction_stack;
4010 thread->transaction_stack = t;
4011 binder_inner_proc_unlock(proc);
4012 return_error = binder_proc_transaction(t,
4013 target_proc, target_thread);
4014 if (return_error) {
4015 binder_inner_proc_lock(proc);
4016 binder_pop_transaction_ilocked(thread, t);
4017 binder_inner_proc_unlock(proc);
4018 goto err_dead_proc_or_thread;
4019 }
4020 } else {
4021 BUG_ON(target_node == NULL);
4022 BUG_ON(t->buffer->async_transaction != 1);
4023 return_error = binder_proc_transaction(t, target_proc, NULL);
4024 /*
4025 * Let the caller know when async transaction reaches a frozen
4026 * process and is put in a pending queue, waiting for the target
4027 * process to be unfrozen.
4028 */
4029 if (return_error == BR_TRANSACTION_PENDING_FROZEN) {
4030 tcomplete->type = BINDER_WORK_TRANSACTION_PENDING;
4031 binder_netlink_report(proc, t, tr->data_size,
4032 return_error, reply);
4033 }
4034 binder_enqueue_thread_work(thread, tcomplete);
4035 if (return_error &&
4036 return_error != BR_TRANSACTION_PENDING_FROZEN)
4037 goto err_dead_proc_or_thread;
4038 }
4039 if (target_thread)
4040 binder_thread_dec_tmpref(target_thread);
4041 binder_proc_dec_tmpref(target_proc);
4042 if (target_node)
4043 binder_dec_node_tmpref(target_node);
4044 /*
4045 * write barrier to synchronize with initialization
4046 * of log entry
4047 */
4048 smp_wmb();
4049 WRITE_ONCE(e->debug_id_done, t_debug_id);
4050 return;
4051
4052 err_dead_proc_or_thread:
4053 binder_txn_error("%d:%d dead process or thread\n",
4054 thread->pid, proc->pid);
4055 return_error_line = __LINE__;
4056 binder_dequeue_work(proc, tcomplete);
4057 err_translate_failed:
4058 err_bad_object_type:
4059 err_bad_offset:
4060 err_bad_parent:
4061 err_copy_data_failed:
4062 binder_cleanup_deferred_txn_lists(&sgc_head, &pf_head);
4063 binder_free_txn_fixups(t);
4064 trace_binder_transaction_failed_buffer_release(t->buffer);
4065 binder_transaction_buffer_release(target_proc, NULL, t->buffer,
4066 buffer_offset, true);
4067 if (target_node)
4068 binder_dec_node_tmpref(target_node);
4069 target_node = NULL;
4070 t->buffer->transaction = NULL;
4071 binder_alloc_free_buf(&target_proc->alloc, t->buffer);
4072 err_binder_alloc_buf_failed:
4073 err_bad_extra_size:
4074 if (secctx)
4075 security_release_secctx(secctx, secctx_sz);
4076 err_get_secctx_failed:
4077 kfree(tcomplete);
4078 binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4079 err_alloc_tcomplete_failed:
4080 if (trace_binder_txn_latency_free_enabled())
4081 binder_txn_latency_free(t);
4082 err_bad_todo_list:
4083 err_bad_call_stack:
4084 err_empty_call_stack:
4085 err_dead_binder:
4086 err_invalid_target_handle:
4087 if (target_node) {
4088 binder_dec_node(target_node, 1, 0);
4089 binder_dec_node_tmpref(target_node);
4090 }
4091
4092 binder_netlink_report(proc, t, tr->data_size, return_error, reply);
4093 kfree(t);
4094 binder_stats_deleted(BINDER_STAT_TRANSACTION);
4095 err_alloc_t_failed:
4096
4097 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
4098 "%d:%d transaction %s to %d:%d failed %d/%d/%d, code %u size %lld-%lld line %d\n",
4099 proc->pid, thread->pid, reply ? "reply" :
4100 (tr->flags & TF_ONE_WAY ? "async" : "call"),
4101 target_proc ? target_proc->pid : 0,
4102 target_thread ? target_thread->pid : 0,
4103 t_debug_id, return_error, return_error_param,
4104 tr->code, (u64)tr->data_size, (u64)tr->offsets_size,
4105 return_error_line);
4106
4107 if (target_thread)
4108 binder_thread_dec_tmpref(target_thread);
4109 if (target_proc)
4110 binder_proc_dec_tmpref(target_proc);
4111
4112 {
4113 struct binder_transaction_log_entry *fe;
4114
4115 e->return_error = return_error;
4116 e->return_error_param = return_error_param;
4117 e->return_error_line = return_error_line;
4118 fe = binder_transaction_log_add(&binder_transaction_log_failed);
4119 *fe = *e;
4120 /*
4121 * write barrier to synchronize with initialization
4122 * of log entry
4123 */
4124 smp_wmb();
4125 WRITE_ONCE(e->debug_id_done, t_debug_id);
4126 WRITE_ONCE(fe->debug_id_done, t_debug_id);
4127 }
4128
4129 BUG_ON(thread->return_error.cmd != BR_OK);
4130 if (in_reply_to) {
4131 trace_android_vh_binder_restore_priority(in_reply_to, current);
4132 binder_restore_priority(thread, &in_reply_to->saved_priority);
4133 binder_set_txn_from_error(in_reply_to, t_debug_id,
4134 return_error, return_error_param);
4135 thread->return_error.cmd = BR_TRANSACTION_COMPLETE;
4136 binder_enqueue_thread_work(thread, &thread->return_error.work);
4137 binder_send_failed_reply(in_reply_to, return_error);
4138 } else {
4139 binder_inner_proc_lock(proc);
4140 binder_set_extended_error(&thread->ee, t_debug_id,
4141 return_error, return_error_param);
4142 binder_inner_proc_unlock(proc);
4143 thread->return_error.cmd = return_error;
4144 binder_enqueue_thread_work(thread, &thread->return_error.work);
4145 }
4146 }
4147
4148 static int
binder_request_freeze_notification(struct binder_proc * proc,struct binder_thread * thread,struct binder_handle_cookie * handle_cookie)4149 binder_request_freeze_notification(struct binder_proc *proc,
4150 struct binder_thread *thread,
4151 struct binder_handle_cookie *handle_cookie)
4152 {
4153 struct binder_ref_freeze *freeze;
4154 struct binder_ref *ref;
4155
4156 freeze = kzalloc(sizeof(*freeze), GFP_KERNEL);
4157 if (!freeze)
4158 return -ENOMEM;
4159 binder_proc_lock(proc);
4160 ref = binder_get_ref_olocked(proc, handle_cookie->handle, false);
4161 if (!ref) {
4162 binder_user_error("%d:%d BC_REQUEST_FREEZE_NOTIFICATION invalid ref %d\n",
4163 proc->pid, thread->pid, handle_cookie->handle);
4164 binder_proc_unlock(proc);
4165 kfree(freeze);
4166 return -EINVAL;
4167 }
4168
4169 binder_node_lock(ref->node);
4170 if (ref->freeze) {
4171 binder_user_error("%d:%d BC_REQUEST_FREEZE_NOTIFICATION already set\n",
4172 proc->pid, thread->pid);
4173 binder_node_unlock(ref->node);
4174 binder_proc_unlock(proc);
4175 kfree(freeze);
4176 return -EINVAL;
4177 }
4178
4179 binder_stats_created(BINDER_STAT_FREEZE);
4180 INIT_LIST_HEAD(&freeze->work.entry);
4181 freeze->cookie = handle_cookie->cookie;
4182 freeze->work.type = BINDER_WORK_FROZEN_BINDER;
4183 ref->freeze = freeze;
4184
4185 if (ref->node->proc) {
4186 binder_inner_proc_lock(ref->node->proc);
4187 freeze->is_frozen = ref->node->proc->is_frozen;
4188 binder_inner_proc_unlock(ref->node->proc);
4189
4190 binder_inner_proc_lock(proc);
4191 binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
4192 binder_wakeup_proc_ilocked(proc);
4193 binder_inner_proc_unlock(proc);
4194 }
4195
4196 binder_node_unlock(ref->node);
4197 binder_proc_unlock(proc);
4198 return 0;
4199 }
4200
4201 static int
binder_clear_freeze_notification(struct binder_proc * proc,struct binder_thread * thread,struct binder_handle_cookie * handle_cookie)4202 binder_clear_freeze_notification(struct binder_proc *proc,
4203 struct binder_thread *thread,
4204 struct binder_handle_cookie *handle_cookie)
4205 {
4206 struct binder_ref_freeze *freeze;
4207 struct binder_ref *ref;
4208
4209 binder_proc_lock(proc);
4210 ref = binder_get_ref_olocked(proc, handle_cookie->handle, false);
4211 if (!ref) {
4212 binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION invalid ref %d\n",
4213 proc->pid, thread->pid, handle_cookie->handle);
4214 binder_proc_unlock(proc);
4215 return -EINVAL;
4216 }
4217
4218 binder_node_lock(ref->node);
4219
4220 if (!ref->freeze) {
4221 binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION freeze notification not active\n",
4222 proc->pid, thread->pid);
4223 binder_node_unlock(ref->node);
4224 binder_proc_unlock(proc);
4225 return -EINVAL;
4226 }
4227 freeze = ref->freeze;
4228 binder_inner_proc_lock(proc);
4229 if (freeze->cookie != handle_cookie->cookie) {
4230 binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION freeze notification cookie mismatch %016llx != %016llx\n",
4231 proc->pid, thread->pid, (u64)freeze->cookie,
4232 (u64)handle_cookie->cookie);
4233 binder_inner_proc_unlock(proc);
4234 binder_node_unlock(ref->node);
4235 binder_proc_unlock(proc);
4236 return -EINVAL;
4237 }
4238 ref->freeze = NULL;
4239 /*
4240 * Take the existing freeze object and overwrite its work type. There are three cases here:
4241 * 1. No pending notification. In this case just add the work to the queue.
4242 * 2. A notification was sent and is pending an ack from userspace. Once an ack arrives, we
4243 * should resend with the new work type.
4244 * 3. A notification is pending to be sent. Since the work is already in the queue, nothing
4245 * needs to be done here.
4246 */
4247 freeze->work.type = BINDER_WORK_CLEAR_FREEZE_NOTIFICATION;
4248 if (list_empty(&freeze->work.entry)) {
4249 binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
4250 binder_wakeup_proc_ilocked(proc);
4251 } else if (freeze->sent) {
4252 freeze->resend = true;
4253 }
4254 binder_inner_proc_unlock(proc);
4255 binder_node_unlock(ref->node);
4256 binder_proc_unlock(proc);
4257 return 0;
4258 }
4259
4260 static int
binder_freeze_notification_done(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t cookie)4261 binder_freeze_notification_done(struct binder_proc *proc,
4262 struct binder_thread *thread,
4263 binder_uintptr_t cookie)
4264 {
4265 struct binder_ref_freeze *freeze = NULL;
4266 struct binder_work *w;
4267
4268 binder_inner_proc_lock(proc);
4269 list_for_each_entry(w, &proc->delivered_freeze, entry) {
4270 struct binder_ref_freeze *tmp_freeze =
4271 container_of(w, struct binder_ref_freeze, work);
4272
4273 if (tmp_freeze->cookie == cookie) {
4274 freeze = tmp_freeze;
4275 break;
4276 }
4277 }
4278 if (!freeze) {
4279 binder_user_error("%d:%d BC_FREEZE_NOTIFICATION_DONE %016llx not found\n",
4280 proc->pid, thread->pid, (u64)cookie);
4281 binder_inner_proc_unlock(proc);
4282 return -EINVAL;
4283 }
4284 binder_dequeue_work_ilocked(&freeze->work);
4285 freeze->sent = false;
4286 if (freeze->resend) {
4287 freeze->resend = false;
4288 binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
4289 binder_wakeup_proc_ilocked(proc);
4290 }
4291 binder_inner_proc_unlock(proc);
4292 return 0;
4293 }
4294
4295 /**
4296 * binder_free_buf() - free the specified buffer
4297 * @proc: binder proc that owns buffer
4298 * @buffer: buffer to be freed
4299 * @is_failure: failed to send transaction
4300 *
4301 * If buffer for an async transaction, enqueue the next async
4302 * transaction from the node.
4303 *
4304 * Cleanup buffer and free it.
4305 */
4306 static void
binder_free_buf(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)4307 binder_free_buf(struct binder_proc *proc,
4308 struct binder_thread *thread,
4309 struct binder_buffer *buffer, bool is_failure)
4310 {
4311 bool enqueue_task = true;
4312 bool has_transaction = false;
4313
4314 binder_inner_proc_lock(proc);
4315 if (buffer->transaction) {
4316 buffer->transaction->buffer = NULL;
4317 buffer->transaction = NULL;
4318 has_transaction = true;
4319 }
4320 binder_inner_proc_unlock(proc);
4321 if (buffer->async_transaction && buffer->target_node) {
4322 struct binder_node *buf_node;
4323 struct binder_work *w;
4324
4325 buf_node = buffer->target_node;
4326 binder_node_inner_lock(buf_node);
4327 BUG_ON(!buf_node->has_async_transaction);
4328 BUG_ON(buf_node->proc != proc);
4329 w = binder_dequeue_work_head_ilocked(
4330 &buf_node->async_todo);
4331 if (!w) {
4332 buf_node->has_async_transaction = false;
4333 } else {
4334 trace_android_vh_binder_special_task(NULL, proc, thread, w,
4335 &proc->todo, false, &enqueue_task);
4336 if (enqueue_task)
4337 binder_enqueue_work_ilocked(w, &proc->todo);
4338 binder_wakeup_proc_ilocked(proc);
4339 }
4340 binder_node_inner_unlock(buf_node);
4341 }
4342 trace_android_vh_binder_buffer_release(proc, thread, buffer,
4343 has_transaction);
4344 trace_binder_transaction_buffer_release(buffer);
4345 binder_release_entire_buffer(proc, thread, buffer, is_failure);
4346 binder_alloc_free_buf(&proc->alloc, buffer);
4347 }
4348
binder_thread_write(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed)4349 static int binder_thread_write(struct binder_proc *proc,
4350 struct binder_thread *thread,
4351 binder_uintptr_t binder_buffer, size_t size,
4352 binder_size_t *consumed)
4353 {
4354 uint32_t cmd;
4355 struct binder_context *context = proc->context;
4356 void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4357 void __user *ptr = buffer + *consumed;
4358 void __user *end = buffer + size;
4359
4360 while (ptr < end && thread->return_error.cmd == BR_OK) {
4361 int ret;
4362
4363 if (get_user(cmd, (uint32_t __user *)ptr))
4364 return -EFAULT;
4365 ptr += sizeof(uint32_t);
4366 trace_binder_command(cmd);
4367 if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) {
4368 atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]);
4369 atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]);
4370 atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]);
4371 }
4372 switch (cmd) {
4373 case BC_INCREFS:
4374 case BC_ACQUIRE:
4375 case BC_RELEASE:
4376 case BC_DECREFS: {
4377 uint32_t target;
4378 const char *debug_string;
4379 bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
4380 bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
4381 struct binder_ref_data rdata;
4382
4383 if (get_user(target, (uint32_t __user *)ptr))
4384 return -EFAULT;
4385
4386 ptr += sizeof(uint32_t);
4387 ret = -1;
4388 if (increment && !target) {
4389 struct binder_node *ctx_mgr_node;
4390
4391 mutex_lock(&context->context_mgr_node_lock);
4392 ctx_mgr_node = context->binder_context_mgr_node;
4393 if (ctx_mgr_node) {
4394 if (ctx_mgr_node->proc == proc) {
4395 binder_user_error("%d:%d context manager tried to acquire desc 0\n",
4396 proc->pid, thread->pid);
4397 mutex_unlock(&context->context_mgr_node_lock);
4398 return -EINVAL;
4399 }
4400 ret = binder_inc_ref_for_node(
4401 proc, ctx_mgr_node,
4402 strong, NULL, &rdata);
4403 }
4404 mutex_unlock(&context->context_mgr_node_lock);
4405 }
4406 if (ret)
4407 ret = binder_update_ref_for_handle(
4408 proc, target, increment, strong,
4409 &rdata);
4410 if (!ret && rdata.desc != target) {
4411 binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
4412 proc->pid, thread->pid,
4413 target, rdata.desc);
4414 }
4415 switch (cmd) {
4416 case BC_INCREFS:
4417 debug_string = "IncRefs";
4418 break;
4419 case BC_ACQUIRE:
4420 debug_string = "Acquire";
4421 break;
4422 case BC_RELEASE:
4423 debug_string = "Release";
4424 break;
4425 case BC_DECREFS:
4426 default:
4427 debug_string = "DecRefs";
4428 break;
4429 }
4430 if (ret) {
4431 binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
4432 proc->pid, thread->pid, debug_string,
4433 strong, target, ret);
4434 break;
4435 }
4436 binder_debug(BINDER_DEBUG_USER_REFS,
4437 "%d:%d %s ref %d desc %d s %d w %d\n",
4438 proc->pid, thread->pid, debug_string,
4439 rdata.debug_id, rdata.desc, rdata.strong,
4440 rdata.weak);
4441 break;
4442 }
4443 case BC_INCREFS_DONE:
4444 case BC_ACQUIRE_DONE: {
4445 binder_uintptr_t node_ptr;
4446 binder_uintptr_t cookie;
4447 struct binder_node *node;
4448 bool free_node;
4449
4450 if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
4451 return -EFAULT;
4452 ptr += sizeof(binder_uintptr_t);
4453 if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4454 return -EFAULT;
4455 ptr += sizeof(binder_uintptr_t);
4456 node = binder_get_node(proc, node_ptr);
4457 if (node == NULL) {
4458 binder_user_error("%d:%d %s u%016llx no match\n",
4459 proc->pid, thread->pid,
4460 cmd == BC_INCREFS_DONE ?
4461 "BC_INCREFS_DONE" :
4462 "BC_ACQUIRE_DONE",
4463 (u64)node_ptr);
4464 break;
4465 }
4466 if (cookie != node->cookie) {
4467 binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n",
4468 proc->pid, thread->pid,
4469 cmd == BC_INCREFS_DONE ?
4470 "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
4471 (u64)node_ptr, node->debug_id,
4472 (u64)cookie, (u64)node->cookie);
4473 binder_put_node(node);
4474 break;
4475 }
4476 binder_node_inner_lock(node);
4477 if (cmd == BC_ACQUIRE_DONE) {
4478 if (node->pending_strong_ref == 0) {
4479 binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n",
4480 proc->pid, thread->pid,
4481 node->debug_id);
4482 binder_node_inner_unlock(node);
4483 binder_put_node(node);
4484 break;
4485 }
4486 node->pending_strong_ref = 0;
4487 } else {
4488 if (node->pending_weak_ref == 0) {
4489 binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n",
4490 proc->pid, thread->pid,
4491 node->debug_id);
4492 binder_node_inner_unlock(node);
4493 binder_put_node(node);
4494 break;
4495 }
4496 node->pending_weak_ref = 0;
4497 }
4498 free_node = binder_dec_node_nilocked(node,
4499 cmd == BC_ACQUIRE_DONE, 0);
4500 WARN_ON(free_node);
4501 binder_debug(BINDER_DEBUG_USER_REFS,
4502 "%d:%d %s node %d ls %d lw %d tr %d\n",
4503 proc->pid, thread->pid,
4504 cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
4505 node->debug_id, node->local_strong_refs,
4506 node->local_weak_refs, node->tmp_refs);
4507 binder_node_inner_unlock(node);
4508 binder_put_node(node);
4509 break;
4510 }
4511 case BC_ATTEMPT_ACQUIRE:
4512 pr_err("BC_ATTEMPT_ACQUIRE not supported\n");
4513 return -EINVAL;
4514 case BC_ACQUIRE_RESULT:
4515 pr_err("BC_ACQUIRE_RESULT not supported\n");
4516 return -EINVAL;
4517
4518 case BC_FREE_BUFFER: {
4519 binder_uintptr_t data_ptr;
4520 struct binder_buffer *buffer;
4521
4522 if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
4523 return -EFAULT;
4524 ptr += sizeof(binder_uintptr_t);
4525
4526 buffer = binder_alloc_prepare_to_free(&proc->alloc,
4527 data_ptr);
4528 if (IS_ERR_OR_NULL(buffer)) {
4529 if (PTR_ERR(buffer) == -EPERM) {
4530 binder_user_error(
4531 "%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n",
4532 proc->pid, thread->pid,
4533 (u64)data_ptr);
4534 } else {
4535 binder_user_error(
4536 "%d:%d BC_FREE_BUFFER u%016llx no match\n",
4537 proc->pid, thread->pid,
4538 (u64)data_ptr);
4539 }
4540 break;
4541 }
4542 binder_debug(BINDER_DEBUG_FREE_BUFFER,
4543 "%d:%d BC_FREE_BUFFER u%016llx found buffer %d for %s transaction\n",
4544 proc->pid, thread->pid, (u64)data_ptr,
4545 buffer->debug_id,
4546 buffer->transaction ? "active" : "finished");
4547 binder_free_buf(proc, thread, buffer, false);
4548 break;
4549 }
4550
4551 case BC_TRANSACTION_SG:
4552 case BC_REPLY_SG: {
4553 struct binder_transaction_data_sg tr;
4554
4555 if (copy_from_user(&tr, ptr, sizeof(tr)))
4556 return -EFAULT;
4557 ptr += sizeof(tr);
4558 binder_transaction(proc, thread, &tr.transaction_data,
4559 cmd == BC_REPLY_SG, tr.buffers_size);
4560 break;
4561 }
4562 case BC_TRANSACTION:
4563 case BC_REPLY: {
4564 struct binder_transaction_data tr;
4565
4566 if (copy_from_user(&tr, ptr, sizeof(tr)))
4567 return -EFAULT;
4568 ptr += sizeof(tr);
4569 binder_transaction(proc, thread, &tr,
4570 cmd == BC_REPLY, 0);
4571 break;
4572 }
4573
4574 case BC_REGISTER_LOOPER:
4575 binder_debug(BINDER_DEBUG_THREADS,
4576 "%d:%d BC_REGISTER_LOOPER\n",
4577 proc->pid, thread->pid);
4578 binder_inner_proc_lock(proc);
4579 if (thread->looper & BINDER_LOOPER_STATE_ENTERED) {
4580 thread->looper |= BINDER_LOOPER_STATE_INVALID;
4581 binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n",
4582 proc->pid, thread->pid);
4583 } else if (proc->requested_threads == 0) {
4584 thread->looper |= BINDER_LOOPER_STATE_INVALID;
4585 binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n",
4586 proc->pid, thread->pid);
4587 } else {
4588 proc->requested_threads--;
4589 proc->requested_threads_started++;
4590 }
4591 thread->looper |= BINDER_LOOPER_STATE_REGISTERED;
4592 binder_inner_proc_unlock(proc);
4593 trace_android_vh_binder_looper_state_registered(thread, proc);
4594 break;
4595 case BC_ENTER_LOOPER:
4596 binder_debug(BINDER_DEBUG_THREADS,
4597 "%d:%d BC_ENTER_LOOPER\n",
4598 proc->pid, thread->pid);
4599 if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) {
4600 thread->looper |= BINDER_LOOPER_STATE_INVALID;
4601 binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n",
4602 proc->pid, thread->pid);
4603 }
4604 thread->looper |= BINDER_LOOPER_STATE_ENTERED;
4605 break;
4606 case BC_EXIT_LOOPER:
4607 trace_android_vh_binder_looper_exited(thread, proc);
4608 binder_debug(BINDER_DEBUG_THREADS,
4609 "%d:%d BC_EXIT_LOOPER\n",
4610 proc->pid, thread->pid);
4611 thread->looper |= BINDER_LOOPER_STATE_EXITED;
4612 break;
4613
4614 case BC_REQUEST_DEATH_NOTIFICATION:
4615 case BC_CLEAR_DEATH_NOTIFICATION: {
4616 uint32_t target;
4617 binder_uintptr_t cookie;
4618 struct binder_ref *ref;
4619 struct binder_ref_death *death = NULL;
4620
4621 if (get_user(target, (uint32_t __user *)ptr))
4622 return -EFAULT;
4623 ptr += sizeof(uint32_t);
4624 if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4625 return -EFAULT;
4626 ptr += sizeof(binder_uintptr_t);
4627 if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4628 /*
4629 * Allocate memory for death notification
4630 * before taking lock
4631 */
4632 death = kzalloc(sizeof(*death), GFP_KERNEL);
4633 if (death == NULL) {
4634 WARN_ON(thread->return_error.cmd !=
4635 BR_OK);
4636 thread->return_error.cmd = BR_ERROR;
4637 binder_enqueue_thread_work(
4638 thread,
4639 &thread->return_error.work);
4640 binder_debug(
4641 BINDER_DEBUG_FAILED_TRANSACTION,
4642 "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n",
4643 proc->pid, thread->pid);
4644 break;
4645 }
4646 }
4647 binder_proc_lock(proc);
4648 ref = binder_get_ref_olocked(proc, target, false);
4649 if (ref == NULL) {
4650 binder_user_error("%d:%d %s invalid ref %d\n",
4651 proc->pid, thread->pid,
4652 cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4653 "BC_REQUEST_DEATH_NOTIFICATION" :
4654 "BC_CLEAR_DEATH_NOTIFICATION",
4655 target);
4656 binder_proc_unlock(proc);
4657 kfree(death);
4658 break;
4659 }
4660
4661 binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4662 "%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n",
4663 proc->pid, thread->pid,
4664 cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4665 "BC_REQUEST_DEATH_NOTIFICATION" :
4666 "BC_CLEAR_DEATH_NOTIFICATION",
4667 (u64)cookie, ref->data.debug_id,
4668 ref->data.desc, ref->data.strong,
4669 ref->data.weak, ref->node->debug_id);
4670
4671 binder_node_lock(ref->node);
4672 if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4673 if (ref->death) {
4674 binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n",
4675 proc->pid, thread->pid);
4676 binder_node_unlock(ref->node);
4677 binder_proc_unlock(proc);
4678 kfree(death);
4679 break;
4680 }
4681 binder_stats_created(BINDER_STAT_DEATH);
4682 INIT_LIST_HEAD(&death->work.entry);
4683 death->cookie = cookie;
4684 ref->death = death;
4685 if (ref->node->proc == NULL) {
4686 ref->death->work.type = BINDER_WORK_DEAD_BINDER;
4687
4688 binder_inner_proc_lock(proc);
4689 binder_enqueue_work_ilocked(
4690 &ref->death->work, &proc->todo);
4691 binder_wakeup_proc_ilocked(proc);
4692 binder_inner_proc_unlock(proc);
4693 }
4694 } else {
4695 if (ref->death == NULL) {
4696 binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n",
4697 proc->pid, thread->pid);
4698 binder_node_unlock(ref->node);
4699 binder_proc_unlock(proc);
4700 break;
4701 }
4702 death = ref->death;
4703 if (death->cookie != cookie) {
4704 binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n",
4705 proc->pid, thread->pid,
4706 (u64)death->cookie,
4707 (u64)cookie);
4708 binder_node_unlock(ref->node);
4709 binder_proc_unlock(proc);
4710 break;
4711 }
4712 ref->death = NULL;
4713 binder_inner_proc_lock(proc);
4714 if (list_empty(&death->work.entry)) {
4715 death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4716 if (thread->looper &
4717 (BINDER_LOOPER_STATE_REGISTERED |
4718 BINDER_LOOPER_STATE_ENTERED))
4719 binder_enqueue_thread_work_ilocked(
4720 thread,
4721 &death->work);
4722 else {
4723 binder_enqueue_work_ilocked(
4724 &death->work,
4725 &proc->todo);
4726 binder_wakeup_proc_ilocked(
4727 proc);
4728 }
4729 } else {
4730 BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER);
4731 death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR;
4732 }
4733 binder_inner_proc_unlock(proc);
4734 }
4735 binder_node_unlock(ref->node);
4736 binder_proc_unlock(proc);
4737 } break;
4738 case BC_DEAD_BINDER_DONE: {
4739 struct binder_work *w;
4740 binder_uintptr_t cookie;
4741 struct binder_ref_death *death = NULL;
4742
4743 if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4744 return -EFAULT;
4745
4746 ptr += sizeof(cookie);
4747 binder_inner_proc_lock(proc);
4748 list_for_each_entry(w, &proc->delivered_death,
4749 entry) {
4750 struct binder_ref_death *tmp_death =
4751 container_of(w,
4752 struct binder_ref_death,
4753 work);
4754
4755 if (tmp_death->cookie == cookie) {
4756 death = tmp_death;
4757 break;
4758 }
4759 }
4760 binder_debug(BINDER_DEBUG_DEAD_BINDER,
4761 "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n",
4762 proc->pid, thread->pid, (u64)cookie,
4763 death);
4764 if (death == NULL) {
4765 binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n",
4766 proc->pid, thread->pid, (u64)cookie);
4767 binder_inner_proc_unlock(proc);
4768 break;
4769 }
4770 binder_dequeue_work_ilocked(&death->work);
4771 if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) {
4772 death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4773 if (thread->looper &
4774 (BINDER_LOOPER_STATE_REGISTERED |
4775 BINDER_LOOPER_STATE_ENTERED))
4776 binder_enqueue_thread_work_ilocked(
4777 thread, &death->work);
4778 else {
4779 binder_enqueue_work_ilocked(
4780 &death->work,
4781 &proc->todo);
4782 binder_wakeup_proc_ilocked(proc);
4783 }
4784 }
4785 binder_inner_proc_unlock(proc);
4786 } break;
4787
4788 case BC_REQUEST_FREEZE_NOTIFICATION: {
4789 struct binder_handle_cookie handle_cookie;
4790 int error;
4791
4792 if (copy_from_user(&handle_cookie, ptr, sizeof(handle_cookie)))
4793 return -EFAULT;
4794 ptr += sizeof(handle_cookie);
4795 error = binder_request_freeze_notification(proc, thread,
4796 &handle_cookie);
4797 if (error)
4798 return error;
4799 } break;
4800
4801 case BC_CLEAR_FREEZE_NOTIFICATION: {
4802 struct binder_handle_cookie handle_cookie;
4803 int error;
4804
4805 if (copy_from_user(&handle_cookie, ptr, sizeof(handle_cookie)))
4806 return -EFAULT;
4807 ptr += sizeof(handle_cookie);
4808 error = binder_clear_freeze_notification(proc, thread, &handle_cookie);
4809 if (error)
4810 return error;
4811 } break;
4812
4813 case BC_FREEZE_NOTIFICATION_DONE: {
4814 binder_uintptr_t cookie;
4815 int error;
4816
4817 if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4818 return -EFAULT;
4819
4820 ptr += sizeof(cookie);
4821 error = binder_freeze_notification_done(proc, thread, cookie);
4822 if (error)
4823 return error;
4824 } break;
4825
4826 default:
4827 pr_err("%d:%d unknown command %u\n",
4828 proc->pid, thread->pid, cmd);
4829 return -EINVAL;
4830 }
4831 *consumed = ptr - buffer;
4832 }
4833 return 0;
4834 }
4835
binder_stat_br(struct binder_proc * proc,struct binder_thread * thread,uint32_t cmd)4836 static void binder_stat_br(struct binder_proc *proc,
4837 struct binder_thread *thread, uint32_t cmd)
4838 {
4839 trace_binder_return(cmd);
4840 if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) {
4841 atomic_inc(&binder_stats.br[_IOC_NR(cmd)]);
4842 atomic_inc(&proc->stats.br[_IOC_NR(cmd)]);
4843 atomic_inc(&thread->stats.br[_IOC_NR(cmd)]);
4844 }
4845 }
4846
binder_put_node_cmd(struct binder_proc * proc,struct binder_thread * thread,void __user ** ptrp,binder_uintptr_t node_ptr,binder_uintptr_t node_cookie,int node_debug_id,uint32_t cmd,const char * cmd_name)4847 static int binder_put_node_cmd(struct binder_proc *proc,
4848 struct binder_thread *thread,
4849 void __user **ptrp,
4850 binder_uintptr_t node_ptr,
4851 binder_uintptr_t node_cookie,
4852 int node_debug_id,
4853 uint32_t cmd, const char *cmd_name)
4854 {
4855 void __user *ptr = *ptrp;
4856
4857 if (put_user(cmd, (uint32_t __user *)ptr))
4858 return -EFAULT;
4859 ptr += sizeof(uint32_t);
4860
4861 if (put_user(node_ptr, (binder_uintptr_t __user *)ptr))
4862 return -EFAULT;
4863 ptr += sizeof(binder_uintptr_t);
4864
4865 if (put_user(node_cookie, (binder_uintptr_t __user *)ptr))
4866 return -EFAULT;
4867 ptr += sizeof(binder_uintptr_t);
4868
4869 binder_stat_br(proc, thread, cmd);
4870 binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n",
4871 proc->pid, thread->pid, cmd_name, node_debug_id,
4872 (u64)node_ptr, (u64)node_cookie);
4873
4874 *ptrp = ptr;
4875 return 0;
4876 }
4877
binder_wait_for_work(struct binder_thread * thread,bool do_proc_work)4878 static int binder_wait_for_work(struct binder_thread *thread,
4879 bool do_proc_work)
4880 {
4881 DEFINE_WAIT(wait);
4882 struct binder_proc *proc = thread->proc;
4883 int ret = 0;
4884
4885 binder_inner_proc_lock(proc);
4886 for (;;) {
4887 prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE);
4888 if (binder_has_work_ilocked(thread, do_proc_work))
4889 break;
4890 if (do_proc_work)
4891 list_add(&thread->waiting_thread_node,
4892 &proc->waiting_threads);
4893 trace_android_vh_binder_wait_for_work(do_proc_work, thread, proc);
4894 binder_inner_proc_unlock(proc);
4895 schedule();
4896 binder_inner_proc_lock(proc);
4897 list_del_init(&thread->waiting_thread_node);
4898 if (signal_pending(current)) {
4899 ret = -EINTR;
4900 break;
4901 }
4902 }
4903 finish_wait(&thread->wait, &wait);
4904 binder_inner_proc_unlock(proc);
4905
4906 return ret;
4907 }
4908
4909 /**
4910 * binder_apply_fd_fixups() - finish fd translation
4911 * @proc: binder_proc associated @t->buffer
4912 * @t: binder transaction with list of fd fixups
4913 *
4914 * Now that we are in the context of the transaction target
4915 * process, we can allocate and install fds. Process the
4916 * list of fds to translate and fixup the buffer with the
4917 * new fds first and only then install the files.
4918 *
4919 * If we fail to allocate an fd, skip the install and release
4920 * any fds that have already been allocated.
4921 */
binder_apply_fd_fixups(struct binder_proc * proc,struct binder_transaction * t)4922 static int binder_apply_fd_fixups(struct binder_proc *proc,
4923 struct binder_transaction *t)
4924 {
4925 struct binder_txn_fd_fixup *fixup, *tmp;
4926 int ret = 0;
4927
4928 list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
4929 int fd = get_unused_fd_flags(O_CLOEXEC);
4930
4931 if (fd < 0) {
4932 binder_debug(BINDER_DEBUG_TRANSACTION,
4933 "failed fd fixup txn %d fd %d\n",
4934 t->debug_id, fd);
4935 ret = -ENOMEM;
4936 goto err;
4937 }
4938 binder_debug(BINDER_DEBUG_TRANSACTION,
4939 "fd fixup txn %d fd %d\n",
4940 t->debug_id, fd);
4941 trace_binder_transaction_fd_recv(t, fd, fixup->offset);
4942 fixup->target_fd = fd;
4943 if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer,
4944 fixup->offset, &fd,
4945 sizeof(u32))) {
4946 ret = -EINVAL;
4947 goto err;
4948 }
4949 }
4950 list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
4951 fd_install(fixup->target_fd, fixup->file);
4952 list_del(&fixup->fixup_entry);
4953 kfree(fixup);
4954 }
4955
4956 return ret;
4957
4958 err:
4959 binder_free_txn_fixups(t);
4960 return ret;
4961 }
4962
binder_thread_read(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed,int non_block)4963 static int binder_thread_read(struct binder_proc *proc,
4964 struct binder_thread *thread,
4965 binder_uintptr_t binder_buffer, size_t size,
4966 binder_size_t *consumed, int non_block)
4967 {
4968 void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4969 void __user *ptr = buffer + *consumed;
4970 void __user *end = buffer + size;
4971
4972 int ret = 0;
4973 bool nothing_to_do = false;
4974 bool force_spawn = false;
4975 int wait_for_proc_work;
4976
4977 if (*consumed == 0) {
4978 if (put_user(BR_NOOP, (uint32_t __user *)ptr))
4979 return -EFAULT;
4980 ptr += sizeof(uint32_t);
4981 }
4982
4983 retry:
4984 binder_inner_proc_lock(proc);
4985 wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
4986 binder_inner_proc_unlock(proc);
4987
4988 thread->looper |= BINDER_LOOPER_STATE_WAITING;
4989
4990 trace_binder_wait_for_work(wait_for_proc_work,
4991 !!thread->transaction_stack,
4992 !binder_worklist_empty(proc, &thread->todo));
4993 if (wait_for_proc_work) {
4994 if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4995 BINDER_LOOPER_STATE_ENTERED))) {
4996 binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n",
4997 proc->pid, thread->pid, thread->looper);
4998 wait_event_interruptible(binder_user_error_wait,
4999 binder_stop_on_user_error < 2);
5000 }
5001 trace_android_vh_binder_restore_priority(NULL, current);
5002 binder_restore_priority(thread, &proc->default_priority);
5003 }
5004
5005 if (non_block) {
5006 if (!binder_has_work(thread, wait_for_proc_work))
5007 ret = -EAGAIN;
5008 } else {
5009 ret = binder_wait_for_work(thread, wait_for_proc_work);
5010 }
5011
5012 thread->looper &= ~BINDER_LOOPER_STATE_WAITING;
5013
5014 if (ret)
5015 return ret;
5016
5017 while (1) {
5018 uint32_t cmd;
5019 struct binder_transaction_data_secctx tr;
5020 struct binder_transaction_data *trd = &tr.transaction_data;
5021 struct binder_work *w = NULL;
5022 struct list_head *list = NULL;
5023 struct binder_transaction *t = NULL;
5024 struct binder_thread *t_from;
5025 size_t trsize = sizeof(*trd);
5026
5027 binder_inner_proc_lock(proc);
5028 trace_android_vh_binder_select_special_worklist(&list, thread,
5029 proc, wait_for_proc_work, ¬hing_to_do);
5030 if (list)
5031 goto skip;
5032 else if (nothing_to_do)
5033 goto no_work;
5034
5035 if (!binder_worklist_empty_ilocked(&thread->todo))
5036 list = &thread->todo;
5037 else if (!binder_worklist_empty_ilocked(&proc->todo) &&
5038 wait_for_proc_work)
5039 list = &proc->todo;
5040 else {
5041 no_work:
5042 binder_inner_proc_unlock(proc);
5043
5044 /* no data added */
5045 if (ptr - buffer == 4 && !thread->looper_need_return)
5046 goto retry;
5047 break;
5048 }
5049 skip:
5050 if (end - ptr < sizeof(tr) + 4) {
5051 binder_inner_proc_unlock(proc);
5052 break;
5053 }
5054 trace_android_vh_binder_thread_read(&list, proc, thread);
5055 w = binder_dequeue_work_head_ilocked(list);
5056 if (binder_worklist_empty_ilocked(&thread->todo))
5057 thread->process_todo = false;
5058
5059 switch (w->type) {
5060 case BINDER_WORK_TRANSACTION: {
5061 binder_inner_proc_unlock(proc);
5062 t = container_of(w, struct binder_transaction, work);
5063 } break;
5064 case BINDER_WORK_RETURN_ERROR: {
5065 struct binder_error *e = container_of(
5066 w, struct binder_error, work);
5067
5068 WARN_ON(e->cmd == BR_OK);
5069 binder_inner_proc_unlock(proc);
5070 if (put_user(e->cmd, (uint32_t __user *)ptr))
5071 return -EFAULT;
5072 cmd = e->cmd;
5073 e->cmd = BR_OK;
5074 ptr += sizeof(uint32_t);
5075
5076 binder_stat_br(proc, thread, cmd);
5077 } break;
5078 case BINDER_WORK_TRANSACTION_COMPLETE:
5079 case BINDER_WORK_TRANSACTION_PENDING:
5080 case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
5081 if (proc->oneway_spam_detection_enabled &&
5082 w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
5083 cmd = BR_ONEWAY_SPAM_SUSPECT;
5084 else if (w->type == BINDER_WORK_TRANSACTION_PENDING)
5085 cmd = BR_TRANSACTION_PENDING_FROZEN;
5086 else
5087 cmd = BR_TRANSACTION_COMPLETE;
5088 binder_inner_proc_unlock(proc);
5089 kfree(w);
5090 binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
5091 if (put_user(cmd, (uint32_t __user *)ptr))
5092 return -EFAULT;
5093 ptr += sizeof(uint32_t);
5094
5095 binder_stat_br(proc, thread, cmd);
5096 binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
5097 "%d:%d BR_TRANSACTION_COMPLETE\n",
5098 proc->pid, thread->pid);
5099 } break;
5100 case BINDER_WORK_NODE: {
5101 struct binder_node *node = container_of(w, struct binder_node, work);
5102 int strong, weak;
5103 binder_uintptr_t node_ptr = node->ptr;
5104 binder_uintptr_t node_cookie = node->cookie;
5105 int node_debug_id = node->debug_id;
5106 int has_weak_ref;
5107 int has_strong_ref;
5108 void __user *orig_ptr = ptr;
5109
5110 BUG_ON(proc != node->proc);
5111 strong = node->internal_strong_refs ||
5112 node->local_strong_refs;
5113 weak = !hlist_empty(&node->refs) ||
5114 node->local_weak_refs ||
5115 node->tmp_refs || strong;
5116 has_strong_ref = node->has_strong_ref;
5117 has_weak_ref = node->has_weak_ref;
5118
5119 if (weak && !has_weak_ref) {
5120 node->has_weak_ref = 1;
5121 node->pending_weak_ref = 1;
5122 node->local_weak_refs++;
5123 }
5124 if (strong && !has_strong_ref) {
5125 node->has_strong_ref = 1;
5126 node->pending_strong_ref = 1;
5127 node->local_strong_refs++;
5128 }
5129 if (!strong && has_strong_ref)
5130 node->has_strong_ref = 0;
5131 if (!weak && has_weak_ref)
5132 node->has_weak_ref = 0;
5133 if (!weak && !strong) {
5134 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
5135 "%d:%d node %d u%016llx c%016llx deleted\n",
5136 proc->pid, thread->pid,
5137 node_debug_id,
5138 (u64)node_ptr,
5139 (u64)node_cookie);
5140 rb_erase(&node->rb_node, &proc->nodes);
5141 binder_inner_proc_unlock(proc);
5142 binder_node_lock(node);
5143 /*
5144 * Acquire the node lock before freeing the
5145 * node to serialize with other threads that
5146 * may have been holding the node lock while
5147 * decrementing this node (avoids race where
5148 * this thread frees while the other thread
5149 * is unlocking the node after the final
5150 * decrement)
5151 */
5152 binder_node_unlock(node);
5153 binder_free_node(node);
5154 } else
5155 binder_inner_proc_unlock(proc);
5156
5157 if (weak && !has_weak_ref)
5158 ret = binder_put_node_cmd(
5159 proc, thread, &ptr, node_ptr,
5160 node_cookie, node_debug_id,
5161 BR_INCREFS, "BR_INCREFS");
5162 if (!ret && strong && !has_strong_ref)
5163 ret = binder_put_node_cmd(
5164 proc, thread, &ptr, node_ptr,
5165 node_cookie, node_debug_id,
5166 BR_ACQUIRE, "BR_ACQUIRE");
5167 if (!ret && !strong && has_strong_ref)
5168 ret = binder_put_node_cmd(
5169 proc, thread, &ptr, node_ptr,
5170 node_cookie, node_debug_id,
5171 BR_RELEASE, "BR_RELEASE");
5172 if (!ret && !weak && has_weak_ref)
5173 ret = binder_put_node_cmd(
5174 proc, thread, &ptr, node_ptr,
5175 node_cookie, node_debug_id,
5176 BR_DECREFS, "BR_DECREFS");
5177 if (orig_ptr == ptr)
5178 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
5179 "%d:%d node %d u%016llx c%016llx state unchanged\n",
5180 proc->pid, thread->pid,
5181 node_debug_id,
5182 (u64)node_ptr,
5183 (u64)node_cookie);
5184 if (ret)
5185 return ret;
5186 } break;
5187 case BINDER_WORK_DEAD_BINDER:
5188 case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
5189 case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
5190 struct binder_ref_death *death;
5191 uint32_t cmd;
5192 binder_uintptr_t cookie;
5193
5194 death = container_of(w, struct binder_ref_death, work);
5195 if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION)
5196 cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
5197 else
5198 cmd = BR_DEAD_BINDER;
5199 cookie = death->cookie;
5200
5201 binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
5202 "%d:%d %s %016llx\n",
5203 proc->pid, thread->pid,
5204 cmd == BR_DEAD_BINDER ?
5205 "BR_DEAD_BINDER" :
5206 "BR_CLEAR_DEATH_NOTIFICATION_DONE",
5207 (u64)cookie);
5208 if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) {
5209 binder_inner_proc_unlock(proc);
5210 kfree(death);
5211 binder_stats_deleted(BINDER_STAT_DEATH);
5212 } else {
5213 binder_enqueue_work_ilocked(
5214 w, &proc->delivered_death);
5215 binder_inner_proc_unlock(proc);
5216 }
5217 if (put_user(cmd, (uint32_t __user *)ptr))
5218 return -EFAULT;
5219 ptr += sizeof(uint32_t);
5220 if (put_user(cookie,
5221 (binder_uintptr_t __user *)ptr))
5222 return -EFAULT;
5223 ptr += sizeof(binder_uintptr_t);
5224 binder_stat_br(proc, thread, cmd);
5225 if (cmd == BR_DEAD_BINDER)
5226 goto done; /* DEAD_BINDER notifications can cause transactions */
5227 } break;
5228
5229 case BINDER_WORK_FROZEN_BINDER: {
5230 struct binder_ref_freeze *freeze;
5231 struct binder_frozen_state_info info;
5232
5233 memset(&info, 0, sizeof(info));
5234 freeze = container_of(w, struct binder_ref_freeze, work);
5235 info.is_frozen = freeze->is_frozen;
5236 info.cookie = freeze->cookie;
5237 freeze->sent = true;
5238 binder_enqueue_work_ilocked(w, &proc->delivered_freeze);
5239 binder_inner_proc_unlock(proc);
5240
5241 if (put_user(BR_FROZEN_BINDER, (uint32_t __user *)ptr))
5242 return -EFAULT;
5243 ptr += sizeof(uint32_t);
5244 if (copy_to_user(ptr, &info, sizeof(info)))
5245 return -EFAULT;
5246 ptr += sizeof(info);
5247 binder_stat_br(proc, thread, BR_FROZEN_BINDER);
5248 goto done; /* BR_FROZEN_BINDER notifications can cause transactions */
5249 } break;
5250
5251 case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION: {
5252 struct binder_ref_freeze *freeze =
5253 container_of(w, struct binder_ref_freeze, work);
5254 binder_uintptr_t cookie = freeze->cookie;
5255
5256 binder_inner_proc_unlock(proc);
5257 kfree(freeze);
5258 binder_stats_deleted(BINDER_STAT_FREEZE);
5259 if (put_user(BR_CLEAR_FREEZE_NOTIFICATION_DONE, (uint32_t __user *)ptr))
5260 return -EFAULT;
5261 ptr += sizeof(uint32_t);
5262 if (put_user(cookie, (binder_uintptr_t __user *)ptr))
5263 return -EFAULT;
5264 ptr += sizeof(binder_uintptr_t);
5265 binder_stat_br(proc, thread, BR_CLEAR_FREEZE_NOTIFICATION_DONE);
5266 } break;
5267
5268 default:
5269 binder_inner_proc_unlock(proc);
5270 pr_err("%d:%d: bad work type %d\n",
5271 proc->pid, thread->pid, w->type);
5272 break;
5273 }
5274
5275 if (!t)
5276 continue;
5277
5278 BUG_ON(t->buffer == NULL);
5279 if (t->buffer->target_node) {
5280 struct binder_node *target_node = t->buffer->target_node;
5281
5282 trd->target.ptr = target_node->ptr;
5283 trd->cookie = target_node->cookie;
5284 binder_transaction_priority(thread, t, target_node);
5285 cmd = BR_TRANSACTION;
5286 } else {
5287 trd->target.ptr = 0;
5288 trd->cookie = 0;
5289 cmd = BR_REPLY;
5290 }
5291 trd->code = t->code;
5292 trd->flags = t->flags;
5293 trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid);
5294
5295 t_from = binder_get_txn_from(t);
5296 if (t_from) {
5297 struct task_struct *sender = t_from->proc->tsk;
5298
5299 trd->sender_pid =
5300 task_tgid_nr_ns(sender,
5301 task_active_pid_ns(current));
5302 trace_android_vh_sync_txn_recvd(thread->task, t_from->task);
5303 } else {
5304 trd->sender_pid = 0;
5305 }
5306
5307 ret = binder_apply_fd_fixups(proc, t);
5308 if (ret) {
5309 struct binder_buffer *buffer = t->buffer;
5310 bool oneway = !!(t->flags & TF_ONE_WAY);
5311 int tid = t->debug_id;
5312
5313 if (t_from)
5314 binder_thread_dec_tmpref(t_from);
5315 buffer->transaction = NULL;
5316 binder_cleanup_transaction(t, "fd fixups failed",
5317 BR_FAILED_REPLY);
5318 binder_free_buf(proc, thread, buffer, true);
5319 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
5320 "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
5321 proc->pid, thread->pid,
5322 oneway ? "async " :
5323 (cmd == BR_REPLY ? "reply " : ""),
5324 tid, BR_FAILED_REPLY, ret, __LINE__);
5325 if (cmd == BR_REPLY) {
5326 cmd = BR_FAILED_REPLY;
5327 if (put_user(cmd, (uint32_t __user *)ptr))
5328 return -EFAULT;
5329 ptr += sizeof(uint32_t);
5330 binder_stat_br(proc, thread, cmd);
5331 break;
5332 }
5333 continue;
5334 }
5335 trd->data_size = t->buffer->data_size;
5336 trd->offsets_size = t->buffer->offsets_size;
5337 trd->data.ptr.buffer = t->buffer->user_data;
5338 trd->data.ptr.offsets = trd->data.ptr.buffer +
5339 ALIGN(t->buffer->data_size,
5340 sizeof(void *));
5341
5342 tr.secctx = t->security_ctx;
5343 if (t->security_ctx) {
5344 cmd = BR_TRANSACTION_SEC_CTX;
5345 trsize = sizeof(tr);
5346 }
5347 if (put_user(cmd, (uint32_t __user *)ptr)) {
5348 if (t_from)
5349 binder_thread_dec_tmpref(t_from);
5350
5351 binder_cleanup_transaction(t, "put_user failed",
5352 BR_FAILED_REPLY);
5353
5354 return -EFAULT;
5355 }
5356 ptr += sizeof(uint32_t);
5357 if (copy_to_user(ptr, &tr, trsize)) {
5358 if (t_from)
5359 binder_thread_dec_tmpref(t_from);
5360
5361 binder_cleanup_transaction(t, "copy_to_user failed",
5362 BR_FAILED_REPLY);
5363
5364 return -EFAULT;
5365 }
5366 ptr += trsize;
5367
5368 trace_binder_transaction_received(t);
5369 trace_android_vh_binder_transaction_received(t, proc, thread, cmd);
5370 binder_stat_br(proc, thread, cmd);
5371 binder_debug(BINDER_DEBUG_TRANSACTION,
5372 "%d:%d %s %d %d:%d, cmd %u size %zd-%zd ptr %016llx-%016llx\n",
5373 proc->pid, thread->pid,
5374 (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
5375 (cmd == BR_TRANSACTION_SEC_CTX) ?
5376 "BR_TRANSACTION_SEC_CTX" : "BR_REPLY",
5377 t->debug_id, t_from ? t_from->proc->pid : 0,
5378 t_from ? t_from->pid : 0, cmd,
5379 t->buffer->data_size, t->buffer->offsets_size,
5380 (u64)trd->data.ptr.buffer,
5381 (u64)trd->data.ptr.offsets);
5382
5383 if (t_from)
5384 binder_thread_dec_tmpref(t_from);
5385 t->buffer->allow_user_free = 1;
5386 if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) {
5387 binder_inner_proc_lock(thread->proc);
5388 t->to_parent = thread->transaction_stack;
5389 t->to_thread = thread;
5390 thread->transaction_stack = t;
5391 binder_inner_proc_unlock(thread->proc);
5392 } else {
5393 binder_free_transaction(t);
5394 }
5395 break;
5396 }
5397
5398 done:
5399
5400 *consumed = ptr - buffer;
5401 binder_inner_proc_lock(proc);
5402 trace_android_vh_binder_spawn_new_thread(thread, proc, &force_spawn);
5403
5404 if (force_spawn || (proc->requested_threads == 0 &&
5405 list_empty(&thread->proc->waiting_threads) &&
5406 proc->requested_threads_started < proc->max_threads &&
5407 (thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
5408 BINDER_LOOPER_STATE_ENTERED)))/* the user-space code fails to */
5409 /*spawn a new thread if we leave this out */) {
5410 proc->requested_threads++;
5411 binder_inner_proc_unlock(proc);
5412 binder_debug(BINDER_DEBUG_THREADS,
5413 "%d:%d BR_SPAWN_LOOPER\n",
5414 proc->pid, thread->pid);
5415 if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
5416 return -EFAULT;
5417 binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
5418 } else
5419 binder_inner_proc_unlock(proc);
5420 return 0;
5421 }
5422
binder_release_work(struct binder_proc * proc,struct list_head * list)5423 static void binder_release_work(struct binder_proc *proc,
5424 struct list_head *list)
5425 {
5426 struct binder_work *w;
5427 enum binder_work_type wtype;
5428
5429 while (1) {
5430 binder_inner_proc_lock(proc);
5431 w = binder_dequeue_work_head_ilocked(list);
5432 wtype = w ? w->type : 0;
5433 binder_inner_proc_unlock(proc);
5434 if (!w)
5435 return;
5436
5437 switch (wtype) {
5438 case BINDER_WORK_TRANSACTION: {
5439 struct binder_transaction *t;
5440
5441 t = container_of(w, struct binder_transaction, work);
5442
5443 binder_cleanup_transaction(t, "process died.",
5444 BR_DEAD_REPLY);
5445 } break;
5446 case BINDER_WORK_RETURN_ERROR: {
5447 struct binder_error *e = container_of(
5448 w, struct binder_error, work);
5449
5450 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5451 "undelivered TRANSACTION_ERROR: %u\n",
5452 e->cmd);
5453 } break;
5454 case BINDER_WORK_TRANSACTION_PENDING:
5455 case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT:
5456 case BINDER_WORK_TRANSACTION_COMPLETE: {
5457 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5458 "undelivered TRANSACTION_COMPLETE\n");
5459 kfree(w);
5460 binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
5461 } break;
5462 case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
5463 case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
5464 struct binder_ref_death *death;
5465
5466 death = container_of(w, struct binder_ref_death, work);
5467 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5468 "undelivered death notification, %016llx\n",
5469 (u64)death->cookie);
5470 kfree(death);
5471 binder_stats_deleted(BINDER_STAT_DEATH);
5472 } break;
5473 case BINDER_WORK_NODE:
5474 break;
5475 case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION: {
5476 struct binder_ref_freeze *freeze;
5477
5478 freeze = container_of(w, struct binder_ref_freeze, work);
5479 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5480 "undelivered freeze notification, %016llx\n",
5481 (u64)freeze->cookie);
5482 kfree(freeze);
5483 binder_stats_deleted(BINDER_STAT_FREEZE);
5484 } break;
5485 default:
5486 pr_err("unexpected work type, %d, not freed\n",
5487 wtype);
5488 break;
5489 }
5490 }
5491
5492 }
5493
binder_get_thread_ilocked(struct binder_proc * proc,struct binder_thread * new_thread)5494 static struct binder_thread *binder_get_thread_ilocked(
5495 struct binder_proc *proc, struct binder_thread *new_thread)
5496 {
5497 struct binder_thread *thread = NULL;
5498 struct rb_node *parent = NULL;
5499 struct rb_node **p = &proc->threads.rb_node;
5500
5501 while (*p) {
5502 parent = *p;
5503 thread = rb_entry(parent, struct binder_thread, rb_node);
5504
5505 if (current->pid < thread->pid)
5506 p = &(*p)->rb_left;
5507 else if (current->pid > thread->pid)
5508 p = &(*p)->rb_right;
5509 else
5510 return thread;
5511 }
5512 if (!new_thread)
5513 return NULL;
5514 thread = new_thread;
5515 binder_stats_created(BINDER_STAT_THREAD);
5516 thread->proc = proc;
5517 thread->pid = current->pid;
5518 get_task_struct(current);
5519 thread->task = current;
5520 atomic_set(&thread->tmp_ref, 0);
5521 init_waitqueue_head(&thread->wait);
5522 INIT_LIST_HEAD(&thread->todo);
5523 rb_link_node(&thread->rb_node, parent, p);
5524 rb_insert_color(&thread->rb_node, &proc->threads);
5525 thread->looper_need_return = true;
5526 thread->return_error.work.type = BINDER_WORK_RETURN_ERROR;
5527 thread->return_error.cmd = BR_OK;
5528 thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR;
5529 thread->reply_error.cmd = BR_OK;
5530 spin_lock_init(&thread->prio_lock);
5531 thread->prio_state = BINDER_PRIO_SET;
5532 thread->ee.command = BR_OK;
5533 INIT_LIST_HEAD(&new_thread->waiting_thread_node);
5534 return thread;
5535 }
5536
binder_get_thread(struct binder_proc * proc)5537 static struct binder_thread *binder_get_thread(struct binder_proc *proc)
5538 {
5539 struct binder_thread *thread;
5540 struct binder_thread *new_thread;
5541
5542 binder_inner_proc_lock(proc);
5543 thread = binder_get_thread_ilocked(proc, NULL);
5544 binder_inner_proc_unlock(proc);
5545 if (!thread) {
5546 new_thread = kzalloc(sizeof(*thread), GFP_KERNEL);
5547 if (new_thread == NULL)
5548 return NULL;
5549 binder_inner_proc_lock(proc);
5550 thread = binder_get_thread_ilocked(proc, new_thread);
5551 binder_inner_proc_unlock(proc);
5552 if (thread != new_thread)
5553 kfree(new_thread);
5554 }
5555 return thread;
5556 }
5557
binder_free_proc(struct binder_proc * proc)5558 static void binder_free_proc(struct binder_proc *proc)
5559 {
5560 struct binder_device *device;
5561
5562 BUG_ON(!list_empty(&proc->todo));
5563 BUG_ON(!list_empty(&proc->delivered_death));
5564 if (proc->outstanding_txns)
5565 pr_warn("%s: Unexpected outstanding_txns %d\n",
5566 __func__, proc->outstanding_txns);
5567 device = container_of(proc->context, struct binder_device, context);
5568 if (refcount_dec_and_test(&device->ref)) {
5569 kfree(proc->context->name);
5570 kfree(device);
5571 }
5572 binder_alloc_deferred_release(&proc->alloc);
5573 put_task_struct(proc->tsk);
5574 put_cred(proc->cred);
5575 binder_stats_deleted(BINDER_STAT_PROC);
5576 dbitmap_free(&proc->dmap);
5577 trace_android_vh_binder_free_proc(proc);
5578 kfree(proc_wrapper(proc));
5579 }
5580
binder_free_thread(struct binder_thread * thread)5581 static void binder_free_thread(struct binder_thread *thread)
5582 {
5583 BUG_ON(!list_empty(&thread->todo));
5584 binder_stats_deleted(BINDER_STAT_THREAD);
5585 binder_proc_dec_tmpref(thread->proc);
5586 put_task_struct(thread->task);
5587 kfree(thread);
5588 }
5589
binder_thread_release(struct binder_proc * proc,struct binder_thread * thread)5590 static int binder_thread_release(struct binder_proc *proc,
5591 struct binder_thread *thread)
5592 {
5593 struct binder_transaction *t;
5594 struct binder_transaction *send_reply = NULL;
5595 int active_transactions = 0;
5596 struct binder_transaction *last_t = NULL;
5597
5598 binder_inner_proc_lock(thread->proc);
5599 /*
5600 * take a ref on the proc so it survives
5601 * after we remove this thread from proc->threads.
5602 * The corresponding dec is when we actually
5603 * free the thread in binder_free_thread()
5604 */
5605 proc->tmp_ref++;
5606 /*
5607 * take a ref on this thread to ensure it
5608 * survives while we are releasing it
5609 */
5610 atomic_inc(&thread->tmp_ref);
5611 rb_erase(&thread->rb_node, &proc->threads);
5612 t = thread->transaction_stack;
5613 if (t) {
5614 spin_lock(&t->lock);
5615 if (t->to_thread == thread)
5616 send_reply = t;
5617 } else {
5618 __acquire(&t->lock);
5619 }
5620 thread->is_dead = true;
5621
5622 while (t) {
5623 last_t = t;
5624 active_transactions++;
5625 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5626 "release %d:%d transaction %d %s, still active\n",
5627 proc->pid, thread->pid,
5628 t->debug_id,
5629 (t->to_thread == thread) ? "in" : "out");
5630
5631 if (t->to_thread == thread) {
5632 thread->proc->outstanding_txns--;
5633 t->to_proc = NULL;
5634 t->to_thread = NULL;
5635 if (t->buffer) {
5636 t->buffer->transaction = NULL;
5637 t->buffer = NULL;
5638 }
5639 t = t->to_parent;
5640 } else if (t->from == thread) {
5641 t->from = NULL;
5642 t = t->from_parent;
5643 } else
5644 BUG();
5645 spin_unlock(&last_t->lock);
5646 if (t)
5647 spin_lock(&t->lock);
5648 else
5649 __acquire(&t->lock);
5650 }
5651 /* annotation for sparse, lock not acquired in last iteration above */
5652 __release(&t->lock);
5653
5654 /*
5655 * If this thread used poll, make sure we remove the waitqueue from any
5656 * poll data structures holding it.
5657 */
5658 if (thread->looper & BINDER_LOOPER_STATE_POLL)
5659 wake_up_pollfree(&thread->wait);
5660
5661 binder_inner_proc_unlock(thread->proc);
5662
5663 /*
5664 * This is needed to avoid races between wake_up_pollfree() above and
5665 * someone else removing the last entry from the queue for other reasons
5666 * (e.g. ep_remove_wait_queue() being called due to an epoll file
5667 * descriptor being closed). Such other users hold an RCU read lock, so
5668 * we can be sure they're done after we call synchronize_rcu().
5669 */
5670 if (thread->looper & BINDER_LOOPER_STATE_POLL)
5671 synchronize_rcu();
5672
5673 if (send_reply)
5674 binder_send_failed_reply(send_reply, BR_DEAD_REPLY);
5675 binder_release_work(proc, &thread->todo);
5676 trace_android_vh_binder_thread_release(proc, thread);
5677 binder_thread_dec_tmpref(thread);
5678 return active_transactions;
5679 }
5680
binder_poll(struct file * filp,struct poll_table_struct * wait)5681 static __poll_t binder_poll(struct file *filp,
5682 struct poll_table_struct *wait)
5683 {
5684 struct binder_proc *proc = filp->private_data;
5685 struct binder_thread *thread = NULL;
5686 bool wait_for_proc_work;
5687
5688 thread = binder_get_thread(proc);
5689 if (!thread)
5690 return EPOLLERR;
5691
5692 binder_inner_proc_lock(thread->proc);
5693 thread->looper |= BINDER_LOOPER_STATE_POLL;
5694 wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
5695
5696 binder_inner_proc_unlock(thread->proc);
5697
5698 poll_wait(filp, &thread->wait, wait);
5699
5700 if (binder_has_work(thread, wait_for_proc_work))
5701 return EPOLLIN;
5702
5703 return 0;
5704 }
5705
binder_ioctl_write_read(struct file * filp,unsigned long arg,struct binder_thread * thread)5706 static int binder_ioctl_write_read(struct file *filp, unsigned long arg,
5707 struct binder_thread *thread)
5708 {
5709 int ret = 0;
5710 struct binder_proc *proc = filp->private_data;
5711 void __user *ubuf = (void __user *)arg;
5712 struct binder_write_read bwr;
5713 bool has_special_work = false;
5714
5715 if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
5716 ret = -EFAULT;
5717 goto out;
5718 }
5719 binder_debug(BINDER_DEBUG_READ_WRITE,
5720 "%d:%d write %lld at %016llx, read %lld at %016llx\n",
5721 proc->pid, thread->pid,
5722 (u64)bwr.write_size, (u64)bwr.write_buffer,
5723 (u64)bwr.read_size, (u64)bwr.read_buffer);
5724
5725 if (bwr.write_size > 0) {
5726 ret = binder_thread_write(proc, thread,
5727 bwr.write_buffer,
5728 bwr.write_size,
5729 &bwr.write_consumed);
5730 trace_binder_write_done(ret);
5731 if (ret < 0) {
5732 bwr.read_consumed = 0;
5733 if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
5734 ret = -EFAULT;
5735 goto out;
5736 }
5737 }
5738 if (bwr.read_size > 0) {
5739 ret = binder_thread_read(proc, thread, bwr.read_buffer,
5740 bwr.read_size,
5741 &bwr.read_consumed,
5742 filp->f_flags & O_NONBLOCK);
5743 trace_binder_read_done(ret);
5744 binder_inner_proc_lock(proc);
5745 trace_android_vh_binder_has_proc_work_ilocked(
5746 thread, true, &has_special_work);
5747 if (!binder_worklist_empty_ilocked(&proc->todo) || has_special_work)
5748 binder_wakeup_proc_ilocked(proc);
5749 binder_inner_proc_unlock(proc);
5750 trace_android_vh_binder_read_done(proc, thread);
5751 if (ret < 0) {
5752 if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
5753 ret = -EFAULT;
5754 goto out;
5755 }
5756 }
5757 binder_debug(BINDER_DEBUG_READ_WRITE,
5758 "%d:%d wrote %lld of %lld, read return %lld of %lld\n",
5759 proc->pid, thread->pid,
5760 (u64)bwr.write_consumed, (u64)bwr.write_size,
5761 (u64)bwr.read_consumed, (u64)bwr.read_size);
5762 if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
5763 ret = -EFAULT;
5764 goto out;
5765 }
5766 out:
5767 return ret;
5768 }
5769
binder_ioctl_set_ctx_mgr(struct file * filp,struct flat_binder_object * fbo)5770 static int binder_ioctl_set_ctx_mgr(struct file *filp,
5771 struct flat_binder_object *fbo)
5772 {
5773 int ret = 0;
5774 struct binder_proc *proc = filp->private_data;
5775 struct binder_context *context = proc->context;
5776 struct binder_node *new_node;
5777 kuid_t curr_euid = current_euid();
5778
5779 mutex_lock(&context->context_mgr_node_lock);
5780 if (context->binder_context_mgr_node) {
5781 pr_err("BINDER_SET_CONTEXT_MGR already set\n");
5782 ret = -EBUSY;
5783 goto out;
5784 }
5785 ret = security_binder_set_context_mgr(proc->cred);
5786 if (ret < 0)
5787 goto out;
5788 if (uid_valid(context->binder_context_mgr_uid)) {
5789 if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) {
5790 pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
5791 from_kuid(&init_user_ns, curr_euid),
5792 from_kuid(&init_user_ns,
5793 context->binder_context_mgr_uid));
5794 ret = -EPERM;
5795 goto out;
5796 }
5797 } else {
5798 context->binder_context_mgr_uid = curr_euid;
5799 }
5800 new_node = binder_new_node(proc, fbo);
5801 if (!new_node) {
5802 ret = -ENOMEM;
5803 goto out;
5804 }
5805 binder_node_lock(new_node);
5806 new_node->local_weak_refs++;
5807 new_node->local_strong_refs++;
5808 new_node->has_strong_ref = 1;
5809 new_node->has_weak_ref = 1;
5810 context->binder_context_mgr_node = new_node;
5811 binder_node_unlock(new_node);
5812 binder_put_node(new_node);
5813 out:
5814 mutex_unlock(&context->context_mgr_node_lock);
5815 return ret;
5816 }
5817
binder_ioctl_get_node_info_for_ref(struct binder_proc * proc,struct binder_node_info_for_ref * info)5818 static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
5819 struct binder_node_info_for_ref *info)
5820 {
5821 struct binder_node *node;
5822 struct binder_context *context = proc->context;
5823 __u32 handle = info->handle;
5824
5825 if (info->strong_count || info->weak_count || info->reserved1 ||
5826 info->reserved2 || info->reserved3) {
5827 binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
5828 proc->pid);
5829 return -EINVAL;
5830 }
5831
5832 /* This ioctl may only be used by the context manager */
5833 mutex_lock(&context->context_mgr_node_lock);
5834 if (!context->binder_context_mgr_node ||
5835 context->binder_context_mgr_node->proc != proc) {
5836 mutex_unlock(&context->context_mgr_node_lock);
5837 return -EPERM;
5838 }
5839 mutex_unlock(&context->context_mgr_node_lock);
5840
5841 node = binder_get_node_from_ref(proc, handle, true, NULL);
5842 if (!node)
5843 return -EINVAL;
5844
5845 info->strong_count = node->local_strong_refs +
5846 node->internal_strong_refs;
5847 info->weak_count = node->local_weak_refs;
5848
5849 binder_put_node(node);
5850
5851 return 0;
5852 }
5853
binder_ioctl_get_node_debug_info(struct binder_proc * proc,struct binder_node_debug_info * info)5854 static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
5855 struct binder_node_debug_info *info)
5856 {
5857 struct rb_node *n;
5858 binder_uintptr_t ptr = info->ptr;
5859
5860 memset(info, 0, sizeof(*info));
5861
5862 binder_inner_proc_lock(proc);
5863 for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
5864 struct binder_node *node = rb_entry(n, struct binder_node,
5865 rb_node);
5866 if (node->ptr > ptr) {
5867 info->ptr = node->ptr;
5868 info->cookie = node->cookie;
5869 info->has_strong_ref = node->has_strong_ref;
5870 info->has_weak_ref = node->has_weak_ref;
5871 break;
5872 }
5873 }
5874 binder_inner_proc_unlock(proc);
5875
5876 return 0;
5877 }
5878
binder_txns_pending_ilocked(struct binder_proc * proc)5879 static bool binder_txns_pending_ilocked(struct binder_proc *proc)
5880 {
5881 struct rb_node *n;
5882 struct binder_thread *thread;
5883
5884 if (proc->outstanding_txns > 0)
5885 return true;
5886
5887 for (n = rb_first(&proc->threads); n; n = rb_next(n)) {
5888 thread = rb_entry(n, struct binder_thread, rb_node);
5889 if (thread->transaction_stack)
5890 return true;
5891 }
5892 return false;
5893 }
5894
binder_add_freeze_work(struct binder_proc * proc,bool is_frozen)5895 static void binder_add_freeze_work(struct binder_proc *proc, bool is_frozen)
5896 {
5897 struct binder_node *prev = NULL;
5898 struct rb_node *n;
5899 struct binder_ref *ref;
5900
5901 binder_inner_proc_lock(proc);
5902 for (n = rb_first(&proc->nodes); n; n = rb_next(n)) {
5903 struct binder_node *node;
5904
5905 node = rb_entry(n, struct binder_node, rb_node);
5906 binder_inc_node_tmpref_ilocked(node);
5907 binder_inner_proc_unlock(proc);
5908 if (prev)
5909 binder_put_node(prev);
5910 binder_node_lock(node);
5911 hlist_for_each_entry(ref, &node->refs, node_entry) {
5912 /*
5913 * Need the node lock to synchronize
5914 * with new notification requests and the
5915 * inner lock to synchronize with queued
5916 * freeze notifications.
5917 */
5918 binder_inner_proc_lock(ref->proc);
5919 if (!ref->freeze) {
5920 binder_inner_proc_unlock(ref->proc);
5921 continue;
5922 }
5923 ref->freeze->work.type = BINDER_WORK_FROZEN_BINDER;
5924 if (list_empty(&ref->freeze->work.entry)) {
5925 ref->freeze->is_frozen = is_frozen;
5926 binder_enqueue_work_ilocked(&ref->freeze->work, &ref->proc->todo);
5927 binder_wakeup_proc_ilocked(ref->proc);
5928 } else {
5929 if (ref->freeze->sent && ref->freeze->is_frozen != is_frozen)
5930 ref->freeze->resend = true;
5931 ref->freeze->is_frozen = is_frozen;
5932 }
5933 binder_inner_proc_unlock(ref->proc);
5934 }
5935 prev = node;
5936 binder_node_unlock(node);
5937 binder_inner_proc_lock(proc);
5938 if (proc->is_dead)
5939 break;
5940 }
5941 binder_inner_proc_unlock(proc);
5942 if (prev)
5943 binder_put_node(prev);
5944 }
5945
binder_ioctl_freeze(struct binder_freeze_info * info,struct binder_proc * target_proc)5946 static int binder_ioctl_freeze(struct binder_freeze_info *info,
5947 struct binder_proc *target_proc)
5948 {
5949 int ret = 0;
5950
5951 if (!info->enable) {
5952 binder_inner_proc_lock(target_proc);
5953 target_proc->sync_recv = false;
5954 target_proc->async_recv = false;
5955 target_proc->is_frozen = false;
5956 binder_inner_proc_unlock(target_proc);
5957 binder_add_freeze_work(target_proc, false);
5958 return 0;
5959 }
5960
5961 /*
5962 * Freezing the target. Prevent new transactions by
5963 * setting frozen state. If timeout specified, wait
5964 * for transactions to drain.
5965 */
5966 binder_inner_proc_lock(target_proc);
5967 target_proc->sync_recv = false;
5968 target_proc->async_recv = false;
5969 target_proc->is_frozen = true;
5970 binder_inner_proc_unlock(target_proc);
5971
5972 if (info->timeout_ms > 0)
5973 ret = wait_event_interruptible_timeout(
5974 target_proc->freeze_wait,
5975 (!target_proc->outstanding_txns),
5976 msecs_to_jiffies(info->timeout_ms));
5977
5978 /* Check pending transactions that wait for reply */
5979 if (ret >= 0) {
5980 binder_inner_proc_lock(target_proc);
5981 if (binder_txns_pending_ilocked(target_proc))
5982 ret = -EAGAIN;
5983 binder_inner_proc_unlock(target_proc);
5984 }
5985
5986 if (ret < 0) {
5987 binder_inner_proc_lock(target_proc);
5988 target_proc->is_frozen = false;
5989 binder_inner_proc_unlock(target_proc);
5990 } else {
5991 binder_add_freeze_work(target_proc, true);
5992 }
5993
5994 return ret;
5995 }
5996
binder_ioctl_get_freezer_info(struct binder_frozen_status_info * info)5997 static int binder_ioctl_get_freezer_info(
5998 struct binder_frozen_status_info *info)
5999 {
6000 struct binder_proc *target_proc;
6001 bool found = false;
6002 __u32 txns_pending;
6003
6004 info->sync_recv = 0;
6005 info->async_recv = 0;
6006
6007 mutex_lock(&binder_procs_lock);
6008 hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
6009 if (target_proc->pid == info->pid) {
6010 found = true;
6011 binder_inner_proc_lock(target_proc);
6012 txns_pending = binder_txns_pending_ilocked(target_proc);
6013 info->sync_recv |= target_proc->sync_recv |
6014 (txns_pending << 1);
6015 info->async_recv |= target_proc->async_recv;
6016 binder_inner_proc_unlock(target_proc);
6017 }
6018 }
6019 mutex_unlock(&binder_procs_lock);
6020
6021 if (!found)
6022 return -EINVAL;
6023
6024 return 0;
6025 }
6026
binder_ioctl_get_extended_error(struct binder_thread * thread,void __user * ubuf)6027 static int binder_ioctl_get_extended_error(struct binder_thread *thread,
6028 void __user *ubuf)
6029 {
6030 struct binder_extended_error ee;
6031
6032 binder_inner_proc_lock(thread->proc);
6033 ee = thread->ee;
6034 binder_set_extended_error(&thread->ee, 0, BR_OK, 0);
6035 binder_inner_proc_unlock(thread->proc);
6036
6037 if (copy_to_user(ubuf, &ee, sizeof(ee)))
6038 return -EFAULT;
6039
6040 return 0;
6041 }
6042
binder_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)6043 static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
6044 {
6045 int ret;
6046 struct binder_proc *proc = filp->private_data;
6047 struct binder_thread *thread;
6048 void __user *ubuf = (void __user *)arg;
6049
6050 /*pr_info("binder_ioctl: %d:%d %x %lx\n",
6051 proc->pid, current->pid, cmd, arg);*/
6052
6053 binder_selftest_alloc(&proc->alloc);
6054
6055 trace_binder_ioctl(cmd, arg);
6056
6057 ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
6058 if (ret)
6059 goto err_unlocked;
6060
6061 thread = binder_get_thread(proc);
6062 if (thread == NULL) {
6063 ret = -ENOMEM;
6064 goto err;
6065 }
6066
6067 switch (cmd) {
6068 case BINDER_WRITE_READ:
6069 ret = binder_ioctl_write_read(filp, arg, thread);
6070 if (ret)
6071 goto err;
6072 break;
6073 case BINDER_SET_MAX_THREADS: {
6074 u32 max_threads;
6075
6076 if (copy_from_user(&max_threads, ubuf,
6077 sizeof(max_threads))) {
6078 ret = -EINVAL;
6079 goto err;
6080 }
6081 binder_inner_proc_lock(proc);
6082 proc->max_threads = max_threads;
6083 binder_inner_proc_unlock(proc);
6084 break;
6085 }
6086 case BINDER_SET_CONTEXT_MGR_EXT: {
6087 struct flat_binder_object fbo;
6088
6089 if (copy_from_user(&fbo, ubuf, sizeof(fbo))) {
6090 ret = -EINVAL;
6091 goto err;
6092 }
6093 ret = binder_ioctl_set_ctx_mgr(filp, &fbo);
6094 if (ret)
6095 goto err;
6096 break;
6097 }
6098 case BINDER_SET_CONTEXT_MGR:
6099 ret = binder_ioctl_set_ctx_mgr(filp, NULL);
6100 if (ret)
6101 goto err;
6102 break;
6103 case BINDER_THREAD_EXIT:
6104 binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",
6105 proc->pid, thread->pid);
6106 binder_thread_release(proc, thread);
6107 thread = NULL;
6108 break;
6109 case BINDER_VERSION: {
6110 struct binder_version __user *ver = ubuf;
6111
6112 if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
6113 &ver->protocol_version)) {
6114 ret = -EINVAL;
6115 goto err;
6116 }
6117 break;
6118 }
6119 case BINDER_GET_NODE_INFO_FOR_REF: {
6120 struct binder_node_info_for_ref info;
6121
6122 if (copy_from_user(&info, ubuf, sizeof(info))) {
6123 ret = -EFAULT;
6124 goto err;
6125 }
6126
6127 ret = binder_ioctl_get_node_info_for_ref(proc, &info);
6128 if (ret < 0)
6129 goto err;
6130
6131 if (copy_to_user(ubuf, &info, sizeof(info))) {
6132 ret = -EFAULT;
6133 goto err;
6134 }
6135
6136 break;
6137 }
6138 case BINDER_GET_NODE_DEBUG_INFO: {
6139 struct binder_node_debug_info info;
6140
6141 if (copy_from_user(&info, ubuf, sizeof(info))) {
6142 ret = -EFAULT;
6143 goto err;
6144 }
6145
6146 ret = binder_ioctl_get_node_debug_info(proc, &info);
6147 if (ret < 0)
6148 goto err;
6149
6150 if (copy_to_user(ubuf, &info, sizeof(info))) {
6151 ret = -EFAULT;
6152 goto err;
6153 }
6154 break;
6155 }
6156 case BINDER_FREEZE: {
6157 struct binder_freeze_info info;
6158 struct binder_proc **target_procs = NULL, *target_proc;
6159 int target_procs_count = 0, i = 0;
6160
6161 ret = 0;
6162
6163 if (copy_from_user(&info, ubuf, sizeof(info))) {
6164 ret = -EFAULT;
6165 goto err;
6166 }
6167
6168 mutex_lock(&binder_procs_lock);
6169 hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
6170 if (target_proc->pid == info.pid)
6171 target_procs_count++;
6172 }
6173
6174 if (target_procs_count == 0) {
6175 mutex_unlock(&binder_procs_lock);
6176 ret = -EINVAL;
6177 goto err;
6178 }
6179
6180 target_procs = kcalloc(target_procs_count,
6181 sizeof(struct binder_proc *),
6182 GFP_KERNEL);
6183
6184 if (!target_procs) {
6185 mutex_unlock(&binder_procs_lock);
6186 ret = -ENOMEM;
6187 goto err;
6188 }
6189
6190 hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
6191 if (target_proc->pid != info.pid)
6192 continue;
6193
6194 binder_inner_proc_lock(target_proc);
6195 target_proc->tmp_ref++;
6196 binder_inner_proc_unlock(target_proc);
6197
6198 target_procs[i++] = target_proc;
6199 }
6200 mutex_unlock(&binder_procs_lock);
6201
6202 for (i = 0; i < target_procs_count; i++) {
6203 if (ret >= 0)
6204 ret = binder_ioctl_freeze(&info,
6205 target_procs[i]);
6206
6207 binder_proc_dec_tmpref(target_procs[i]);
6208 }
6209
6210 kfree(target_procs);
6211
6212 if (ret < 0)
6213 goto err;
6214 break;
6215 }
6216 case BINDER_GET_FROZEN_INFO: {
6217 struct binder_frozen_status_info info;
6218
6219 if (copy_from_user(&info, ubuf, sizeof(info))) {
6220 ret = -EFAULT;
6221 goto err;
6222 }
6223
6224 ret = binder_ioctl_get_freezer_info(&info);
6225 if (ret < 0)
6226 goto err;
6227
6228 if (copy_to_user(ubuf, &info, sizeof(info))) {
6229 ret = -EFAULT;
6230 goto err;
6231 }
6232 break;
6233 }
6234 case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: {
6235 uint32_t enable;
6236
6237 if (copy_from_user(&enable, ubuf, sizeof(enable))) {
6238 ret = -EFAULT;
6239 goto err;
6240 }
6241 binder_inner_proc_lock(proc);
6242 proc->oneway_spam_detection_enabled = (bool)enable;
6243 binder_inner_proc_unlock(proc);
6244 break;
6245 }
6246 case BINDER_GET_EXTENDED_ERROR:
6247 ret = binder_ioctl_get_extended_error(thread, ubuf);
6248 if (ret < 0)
6249 goto err;
6250 break;
6251 default:
6252 ret = -EINVAL;
6253 goto err;
6254 }
6255 ret = 0;
6256 trace_android_vh_binder_ioctl_end(current, cmd, arg, thread, proc, &ret);
6257 err:
6258 if (thread)
6259 thread->looper_need_return = false;
6260 wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
6261 if (ret && ret != -EINTR)
6262 pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
6263 err_unlocked:
6264 trace_binder_ioctl_done(ret);
6265 return ret;
6266 }
6267
binder_vma_open(struct vm_area_struct * vma)6268 static void binder_vma_open(struct vm_area_struct *vma)
6269 {
6270 struct binder_proc *proc = vma->vm_private_data;
6271
6272 binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6273 "%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
6274 proc->pid, vma->vm_start, vma->vm_end,
6275 (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
6276 (unsigned long)pgprot_val(vma->vm_page_prot));
6277 }
6278
binder_vma_close(struct vm_area_struct * vma)6279 static void binder_vma_close(struct vm_area_struct *vma)
6280 {
6281 struct binder_proc *proc = vma->vm_private_data;
6282
6283 binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6284 "%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
6285 proc->pid, vma->vm_start, vma->vm_end,
6286 (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
6287 (unsigned long)pgprot_val(vma->vm_page_prot));
6288 binder_alloc_vma_close(&proc->alloc);
6289 }
6290
binder_vm_fault(struct vm_fault * vmf)6291 static vm_fault_t binder_vm_fault(struct vm_fault *vmf)
6292 {
6293 return VM_FAULT_SIGBUS;
6294 }
6295
6296 static const struct vm_operations_struct binder_vm_ops = {
6297 .open = binder_vma_open,
6298 .close = binder_vma_close,
6299 .fault = binder_vm_fault,
6300 };
6301
binder_mmap(struct file * filp,struct vm_area_struct * vma)6302 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
6303 {
6304 struct binder_proc *proc = filp->private_data;
6305
6306 if (proc->tsk != current->group_leader)
6307 return -EINVAL;
6308
6309 binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6310 "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
6311 __func__, proc->pid, vma->vm_start, vma->vm_end,
6312 (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
6313 (unsigned long)pgprot_val(vma->vm_page_prot));
6314
6315 if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
6316 pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
6317 proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
6318 return -EPERM;
6319 }
6320 vm_flags_mod(vma, VM_DONTCOPY | VM_MIXEDMAP, VM_MAYWRITE);
6321
6322 vma->vm_ops = &binder_vm_ops;
6323 vma->vm_private_data = proc;
6324
6325 return binder_alloc_mmap_handler(&proc->alloc, vma);
6326 }
6327
binder_open(struct inode * nodp,struct file * filp)6328 static int binder_open(struct inode *nodp, struct file *filp)
6329 {
6330 struct binder_proc_wrap *proc_wrap;
6331 struct binder_proc *proc, *itr;
6332 struct binder_device *binder_dev;
6333 struct binderfs_info *info;
6334 struct dentry *binder_binderfs_dir_entry_proc = NULL;
6335 bool existing_pid = false;
6336
6337 binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
6338 current->group_leader->pid, current->pid);
6339
6340 proc_wrap = kzalloc(sizeof(*proc_wrap), GFP_KERNEL);
6341 if (proc_wrap == NULL)
6342 return -ENOMEM;
6343 proc = &proc_wrap->proc;
6344
6345 dbitmap_init(&proc->dmap);
6346 spin_lock_init(&proc->inner_lock);
6347 spin_lock_init(&proc->outer_lock);
6348 get_task_struct(current->group_leader);
6349 proc->tsk = current->group_leader;
6350 proc->cred = get_cred(filp->f_cred);
6351 INIT_LIST_HEAD(&proc->todo);
6352 init_waitqueue_head(&proc->freeze_wait);
6353 if (binder_supported_policy(current->policy)) {
6354 proc->default_priority.sched_policy = current->policy;
6355 proc->default_priority.prio = current->normal_prio;
6356 } else {
6357 proc->default_priority.sched_policy = SCHED_NORMAL;
6358 proc->default_priority.prio = NICE_TO_PRIO(0);
6359 }
6360
6361 /* binderfs stashes devices in i_private */
6362 if (is_binderfs_device(nodp)) {
6363 binder_dev = nodp->i_private;
6364 info = nodp->i_sb->s_fs_info;
6365 binder_binderfs_dir_entry_proc = info->proc_log_dir;
6366 } else {
6367 binder_dev = container_of(filp->private_data,
6368 struct binder_device, miscdev);
6369 }
6370 refcount_inc(&binder_dev->ref);
6371 proc->context = &binder_dev->context;
6372 binder_alloc_init(&proc->alloc);
6373
6374 binder_stats_created(BINDER_STAT_PROC);
6375 proc->pid = current->group_leader->pid;
6376 INIT_LIST_HEAD(&proc->delivered_death);
6377 INIT_LIST_HEAD(&proc->delivered_freeze);
6378 INIT_LIST_HEAD(&proc->waiting_threads);
6379 filp->private_data = proc;
6380
6381 trace_android_vh_binder_preset(&binder_procs, &binder_procs_lock, proc);
6382 trace_android_vh_binder_data_preset(&binder_procs, &binder_procs_lock,
6383 &binder_transaction_log, &binder_transaction_log_failed,
6384 sizeof(struct binder_transaction_log));
6385 mutex_lock(&binder_procs_lock);
6386 hlist_for_each_entry(itr, &binder_procs, proc_node) {
6387 if (itr->pid == proc->pid) {
6388 existing_pid = true;
6389 break;
6390 }
6391 }
6392 hlist_add_head(&proc->proc_node, &binder_procs);
6393 mutex_unlock(&binder_procs_lock);
6394 if (binder_debugfs_dir_entry_proc && !existing_pid) {
6395 char strbuf[11];
6396
6397 snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
6398 /*
6399 * proc debug entries are shared between contexts.
6400 * Only create for the first PID to avoid debugfs log spamming
6401 * The printing code will anyway print all contexts for a given
6402 * PID so this is not a problem.
6403 */
6404 proc->debugfs_entry = debugfs_create_file(strbuf, 0444,
6405 binder_debugfs_dir_entry_proc,
6406 (void *)(unsigned long)proc->pid,
6407 &proc_fops);
6408 }
6409
6410 if (binder_binderfs_dir_entry_proc && !existing_pid) {
6411 char strbuf[11];
6412 struct dentry *binderfs_entry;
6413
6414 snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
6415 /*
6416 * Similar to debugfs, the process specific log file is shared
6417 * between contexts. Only create for the first PID.
6418 * This is ok since same as debugfs, the log file will contain
6419 * information on all contexts of a given PID.
6420 */
6421 binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc,
6422 strbuf, &proc_fops, (void *)(unsigned long)proc->pid);
6423 if (!IS_ERR(binderfs_entry)) {
6424 proc->binderfs_entry = binderfs_entry;
6425 } else {
6426 int error;
6427
6428 error = PTR_ERR(binderfs_entry);
6429 pr_warn("Unable to create file %s in binderfs (error %d)\n",
6430 strbuf, error);
6431 }
6432 }
6433
6434 return 0;
6435 }
6436
binder_flush(struct file * filp,fl_owner_t id)6437 static int binder_flush(struct file *filp, fl_owner_t id)
6438 {
6439 struct binder_proc *proc = filp->private_data;
6440
6441 binder_defer_work(proc, BINDER_DEFERRED_FLUSH);
6442
6443 return 0;
6444 }
6445
binder_deferred_flush(struct binder_proc * proc)6446 static void binder_deferred_flush(struct binder_proc *proc)
6447 {
6448 struct rb_node *n;
6449 int wake_count = 0;
6450
6451 binder_inner_proc_lock(proc);
6452 for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
6453 struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node);
6454
6455 thread->looper_need_return = true;
6456 if (thread->looper & BINDER_LOOPER_STATE_WAITING) {
6457 wake_up_interruptible(&thread->wait);
6458 wake_count++;
6459 }
6460 }
6461 binder_inner_proc_unlock(proc);
6462
6463 binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6464 "binder_flush: %d woke %d threads\n", proc->pid,
6465 wake_count);
6466 }
6467
binder_release(struct inode * nodp,struct file * filp)6468 static int binder_release(struct inode *nodp, struct file *filp)
6469 {
6470 struct binder_proc *proc = filp->private_data;
6471
6472 debugfs_remove(proc->debugfs_entry);
6473
6474 if (proc->binderfs_entry) {
6475 binderfs_remove_file(proc->binderfs_entry);
6476 proc->binderfs_entry = NULL;
6477 }
6478
6479 binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
6480
6481 return 0;
6482 }
6483
binder_node_release(struct binder_node * node,int refs)6484 static int binder_node_release(struct binder_node *node, int refs)
6485 {
6486 struct binder_ref *ref;
6487 int death = 0;
6488 struct binder_proc *proc = node->proc;
6489
6490 binder_release_work(proc, &node->async_todo);
6491
6492 binder_node_lock(node);
6493 binder_inner_proc_lock(proc);
6494 binder_dequeue_work_ilocked(&node->work);
6495 /*
6496 * The caller must have taken a temporary ref on the node,
6497 */
6498 BUG_ON(!node->tmp_refs);
6499 if (hlist_empty(&node->refs) && node->tmp_refs == 1) {
6500 binder_inner_proc_unlock(proc);
6501 binder_node_unlock(node);
6502 binder_free_node(node);
6503
6504 return refs;
6505 }
6506
6507 node->proc = NULL;
6508 node->local_strong_refs = 0;
6509 node->local_weak_refs = 0;
6510 binder_inner_proc_unlock(proc);
6511
6512 spin_lock(&binder_dead_nodes_lock);
6513 hlist_add_head(&node->dead_node, &binder_dead_nodes);
6514 spin_unlock(&binder_dead_nodes_lock);
6515
6516 hlist_for_each_entry(ref, &node->refs, node_entry) {
6517 refs++;
6518 /*
6519 * Need the node lock to synchronize
6520 * with new notification requests and the
6521 * inner lock to synchronize with queued
6522 * death notifications.
6523 */
6524 binder_inner_proc_lock(ref->proc);
6525 if (!ref->death) {
6526 binder_inner_proc_unlock(ref->proc);
6527 continue;
6528 }
6529
6530 death++;
6531
6532 BUG_ON(!list_empty(&ref->death->work.entry));
6533 ref->death->work.type = BINDER_WORK_DEAD_BINDER;
6534 binder_enqueue_work_ilocked(&ref->death->work,
6535 &ref->proc->todo);
6536 binder_wakeup_proc_ilocked(ref->proc);
6537 binder_inner_proc_unlock(ref->proc);
6538 }
6539
6540 binder_debug(BINDER_DEBUG_DEAD_BINDER,
6541 "node %d now dead, refs %d, death %d\n",
6542 node->debug_id, refs, death);
6543 binder_node_unlock(node);
6544 binder_put_node(node);
6545
6546 return refs;
6547 }
6548
binder_deferred_release(struct binder_proc * proc)6549 static void binder_deferred_release(struct binder_proc *proc)
6550 {
6551 struct binder_context *context = proc->context;
6552 struct rb_node *n;
6553 int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
6554 struct list_head *special_list = NULL;
6555
6556 mutex_lock(&binder_procs_lock);
6557 hlist_del(&proc->proc_node);
6558 mutex_unlock(&binder_procs_lock);
6559
6560 mutex_lock(&context->context_mgr_node_lock);
6561 if (context->binder_context_mgr_node &&
6562 context->binder_context_mgr_node->proc == proc) {
6563 binder_debug(BINDER_DEBUG_DEAD_BINDER,
6564 "%s: %d context_mgr_node gone\n",
6565 __func__, proc->pid);
6566 context->binder_context_mgr_node = NULL;
6567 }
6568 mutex_unlock(&context->context_mgr_node_lock);
6569 binder_inner_proc_lock(proc);
6570 /*
6571 * Make sure proc stays alive after we
6572 * remove all the threads
6573 */
6574 proc->tmp_ref++;
6575
6576 proc->is_dead = true;
6577 proc->is_frozen = false;
6578 proc->sync_recv = false;
6579 proc->async_recv = false;
6580 threads = 0;
6581 active_transactions = 0;
6582 while ((n = rb_first(&proc->threads))) {
6583 struct binder_thread *thread;
6584
6585 thread = rb_entry(n, struct binder_thread, rb_node);
6586 binder_inner_proc_unlock(proc);
6587 threads++;
6588 active_transactions += binder_thread_release(proc, thread);
6589 binder_inner_proc_lock(proc);
6590 }
6591
6592 nodes = 0;
6593 incoming_refs = 0;
6594 while ((n = rb_first(&proc->nodes))) {
6595 struct binder_node *node;
6596
6597 node = rb_entry(n, struct binder_node, rb_node);
6598 nodes++;
6599 /*
6600 * take a temporary ref on the node before
6601 * calling binder_node_release() which will either
6602 * kfree() the node or call binder_put_node()
6603 */
6604 binder_inc_node_tmpref_ilocked(node);
6605 rb_erase(&node->rb_node, &proc->nodes);
6606 binder_inner_proc_unlock(proc);
6607 incoming_refs = binder_node_release(node, incoming_refs);
6608 binder_inner_proc_lock(proc);
6609 }
6610 binder_inner_proc_unlock(proc);
6611
6612 outgoing_refs = 0;
6613 binder_proc_lock(proc);
6614 while ((n = rb_first(&proc->refs_by_desc))) {
6615 struct binder_ref *ref;
6616
6617 ref = rb_entry(n, struct binder_ref, rb_node_desc);
6618 outgoing_refs++;
6619 binder_cleanup_ref_olocked(ref);
6620 binder_proc_unlock(proc);
6621 binder_free_ref(ref);
6622 binder_proc_lock(proc);
6623 }
6624 binder_proc_unlock(proc);
6625
6626 binder_release_work(proc, &proc->todo);
6627 trace_android_vh_binder_check_special_work(proc, &special_list);
6628 if (special_list)
6629 binder_release_work(proc, special_list);
6630 binder_release_work(proc, &proc->delivered_death);
6631 binder_release_work(proc, &proc->delivered_freeze);
6632
6633 binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6634 "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n",
6635 __func__, proc->pid, threads, nodes, incoming_refs,
6636 outgoing_refs, active_transactions);
6637
6638 binder_proc_dec_tmpref(proc);
6639 }
6640
binder_deferred_func(struct work_struct * work)6641 static void binder_deferred_func(struct work_struct *work)
6642 {
6643 struct binder_proc *proc;
6644
6645 int defer;
6646
6647 do {
6648 mutex_lock(&binder_deferred_lock);
6649 if (!hlist_empty(&binder_deferred_list)) {
6650 proc = hlist_entry(binder_deferred_list.first,
6651 struct binder_proc, deferred_work_node);
6652 hlist_del_init(&proc->deferred_work_node);
6653 defer = proc->deferred_work;
6654 proc->deferred_work = 0;
6655 } else {
6656 proc = NULL;
6657 defer = 0;
6658 }
6659 mutex_unlock(&binder_deferred_lock);
6660
6661 if (defer & BINDER_DEFERRED_FLUSH)
6662 binder_deferred_flush(proc);
6663
6664 if (defer & BINDER_DEFERRED_RELEASE)
6665 binder_deferred_release(proc); /* frees proc */
6666 } while (proc);
6667 }
6668 static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
6669
6670 static void
binder_defer_work(struct binder_proc * proc,enum binder_deferred_state defer)6671 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer)
6672 {
6673 mutex_lock(&binder_deferred_lock);
6674 proc->deferred_work |= defer;
6675 if (hlist_unhashed(&proc->deferred_work_node)) {
6676 hlist_add_head(&proc->deferred_work_node,
6677 &binder_deferred_list);
6678 schedule_work(&binder_deferred_work);
6679 }
6680 mutex_unlock(&binder_deferred_lock);
6681 }
6682
print_binder_transaction_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,struct binder_transaction * t)6683 static void print_binder_transaction_ilocked(struct seq_file *m,
6684 struct binder_proc *proc,
6685 const char *prefix,
6686 struct binder_transaction *t)
6687 {
6688 struct binder_proc *to_proc;
6689 struct binder_buffer *buffer = t->buffer;
6690 ktime_t current_time = ktime_get();
6691
6692 spin_lock(&t->lock);
6693 to_proc = t->to_proc;
6694 seq_printf(m,
6695 "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %d:%d r%d elapsed %lldms",
6696 prefix, t->debug_id, t,
6697 t->from_pid,
6698 t->from_tid,
6699 to_proc ? to_proc->pid : 0,
6700 t->to_thread ? t->to_thread->pid : 0,
6701 t->code, t->flags, t->priority.sched_policy,
6702 t->priority.prio, t->need_reply,
6703 ktime_ms_delta(current_time, t->start_time));
6704 spin_unlock(&t->lock);
6705
6706 if (proc != to_proc) {
6707 /*
6708 * Can only safely deref buffer if we are holding the
6709 * correct proc inner lock for this node
6710 */
6711 seq_puts(m, "\n");
6712 return;
6713 }
6714
6715 if (buffer == NULL) {
6716 seq_puts(m, " buffer free\n");
6717 return;
6718 }
6719 if (buffer->target_node)
6720 seq_printf(m, " node %d", buffer->target_node->debug_id);
6721 seq_printf(m, " size %zd:%zd offset %lx\n",
6722 buffer->data_size, buffer->offsets_size,
6723 buffer->user_data - proc->alloc.buffer);
6724 }
6725
print_binder_work_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,const char * transaction_prefix,struct binder_work * w,bool hash_ptrs)6726 static void print_binder_work_ilocked(struct seq_file *m,
6727 struct binder_proc *proc,
6728 const char *prefix,
6729 const char *transaction_prefix,
6730 struct binder_work *w, bool hash_ptrs)
6731 {
6732 struct binder_node *node;
6733 struct binder_transaction *t;
6734
6735 switch (w->type) {
6736 case BINDER_WORK_TRANSACTION:
6737 t = container_of(w, struct binder_transaction, work);
6738 print_binder_transaction_ilocked(
6739 m, proc, transaction_prefix, t);
6740 break;
6741 case BINDER_WORK_RETURN_ERROR: {
6742 struct binder_error *e = container_of(
6743 w, struct binder_error, work);
6744
6745 seq_printf(m, "%stransaction error: %u\n",
6746 prefix, e->cmd);
6747 } break;
6748 case BINDER_WORK_TRANSACTION_COMPLETE:
6749 seq_printf(m, "%stransaction complete\n", prefix);
6750 break;
6751 case BINDER_WORK_NODE:
6752 node = container_of(w, struct binder_node, work);
6753 if (hash_ptrs)
6754 seq_printf(m, "%snode work %d: u%p c%p\n",
6755 prefix, node->debug_id,
6756 (void *)(long)node->ptr,
6757 (void *)(long)node->cookie);
6758 else
6759 seq_printf(m, "%snode work %d: u%016llx c%016llx\n",
6760 prefix, node->debug_id,
6761 (u64)node->ptr, (u64)node->cookie);
6762 break;
6763 case BINDER_WORK_DEAD_BINDER:
6764 seq_printf(m, "%shas dead binder\n", prefix);
6765 break;
6766 case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
6767 seq_printf(m, "%shas cleared dead binder\n", prefix);
6768 break;
6769 case BINDER_WORK_CLEAR_DEATH_NOTIFICATION:
6770 seq_printf(m, "%shas cleared death notification\n", prefix);
6771 break;
6772 case BINDER_WORK_FROZEN_BINDER:
6773 seq_printf(m, "%shas frozen binder\n", prefix);
6774 break;
6775 case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION:
6776 seq_printf(m, "%shas cleared freeze notification\n", prefix);
6777 break;
6778 default:
6779 seq_printf(m, "%sunknown work: type %d\n", prefix, w->type);
6780 break;
6781 }
6782 }
6783
print_binder_thread_ilocked(struct seq_file * m,struct binder_thread * thread,bool print_always,bool hash_ptrs)6784 static void print_binder_thread_ilocked(struct seq_file *m,
6785 struct binder_thread *thread,
6786 bool print_always, bool hash_ptrs)
6787 {
6788 struct binder_transaction *t;
6789 struct binder_work *w;
6790 size_t start_pos = m->count;
6791 size_t header_pos;
6792
6793 seq_printf(m, " thread %d: l %02x need_return %d tr %d\n",
6794 thread->pid, thread->looper,
6795 thread->looper_need_return,
6796 atomic_read(&thread->tmp_ref));
6797 header_pos = m->count;
6798 t = thread->transaction_stack;
6799 while (t) {
6800 if (t->from == thread) {
6801 print_binder_transaction_ilocked(m, thread->proc,
6802 " outgoing transaction", t);
6803 t = t->from_parent;
6804 } else if (t->to_thread == thread) {
6805 print_binder_transaction_ilocked(m, thread->proc,
6806 " incoming transaction", t);
6807 t = t->to_parent;
6808 } else {
6809 print_binder_transaction_ilocked(m, thread->proc,
6810 " bad transaction", t);
6811 t = NULL;
6812 }
6813 }
6814 list_for_each_entry(w, &thread->todo, entry) {
6815 print_binder_work_ilocked(m, thread->proc, " ",
6816 " pending transaction",
6817 w, hash_ptrs);
6818 }
6819 if (!print_always && m->count == header_pos)
6820 m->count = start_pos;
6821 }
6822
print_binder_node_nilocked(struct seq_file * m,struct binder_node * node,bool hash_ptrs)6823 static void print_binder_node_nilocked(struct seq_file *m,
6824 struct binder_node *node,
6825 bool hash_ptrs)
6826 {
6827 struct binder_ref *ref;
6828 struct binder_work *w;
6829 int count;
6830
6831 count = hlist_count_nodes(&node->refs);
6832
6833 if (hash_ptrs)
6834 seq_printf(m, " node %d: u%p c%p", node->debug_id,
6835 (void *)(long)node->ptr, (void *)(long)node->cookie);
6836 else
6837 seq_printf(m, " node %d: u%016llx c%016llx", node->debug_id,
6838 (u64)node->ptr, (u64)node->cookie);
6839 seq_printf(m, " pri %d:%d hs %d hw %d ls %d lw %d is %d iw %d tr %d",
6840 node->sched_policy, node->min_priority,
6841 node->has_strong_ref, node->has_weak_ref,
6842 node->local_strong_refs, node->local_weak_refs,
6843 node->internal_strong_refs, count, node->tmp_refs);
6844 if (count) {
6845 seq_puts(m, " proc");
6846 hlist_for_each_entry(ref, &node->refs, node_entry)
6847 seq_printf(m, " %d", ref->proc->pid);
6848 }
6849 seq_puts(m, "\n");
6850 if (node->proc) {
6851 list_for_each_entry(w, &node->async_todo, entry)
6852 print_binder_work_ilocked(m, node->proc, " ",
6853 " pending async transaction",
6854 w, hash_ptrs);
6855 }
6856 }
6857
print_binder_ref_olocked(struct seq_file * m,struct binder_ref * ref)6858 static void print_binder_ref_olocked(struct seq_file *m,
6859 struct binder_ref *ref)
6860 {
6861 binder_node_lock(ref->node);
6862 seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %pK\n",
6863 ref->data.debug_id, ref->data.desc,
6864 ref->node->proc ? "" : "dead ",
6865 ref->node->debug_id, ref->data.strong,
6866 ref->data.weak, ref->death);
6867 binder_node_unlock(ref->node);
6868 }
6869
6870 /**
6871 * print_next_binder_node_ilocked() - Print binder_node from a locked list
6872 * @m: struct seq_file for output via seq_printf()
6873 * @proc: struct binder_proc we hold the inner_proc_lock to (if any)
6874 * @node: struct binder_node to print fields of
6875 * @prev_node: struct binder_node we hold a temporary reference to (if any)
6876 * @hash_ptrs: whether to hash @node's binder_uintptr_t fields
6877 *
6878 * Helper function to handle synchronization around printing a struct
6879 * binder_node while iterating through @proc->nodes or the dead nodes list.
6880 * Caller must hold either @proc->inner_lock (for live nodes) or
6881 * binder_dead_nodes_lock. This lock will be released during the body of this
6882 * function, but it will be reacquired before returning to the caller.
6883 *
6884 * Return: pointer to the struct binder_node we hold a tmpref on
6885 */
6886 static struct binder_node *
print_next_binder_node_ilocked(struct seq_file * m,struct binder_proc * proc,struct binder_node * node,struct binder_node * prev_node,bool hash_ptrs)6887 print_next_binder_node_ilocked(struct seq_file *m, struct binder_proc *proc,
6888 struct binder_node *node,
6889 struct binder_node *prev_node, bool hash_ptrs)
6890 {
6891 /*
6892 * Take a temporary reference on the node so that isn't freed while
6893 * we print it.
6894 */
6895 binder_inc_node_tmpref_ilocked(node);
6896 /*
6897 * Live nodes need to drop the inner proc lock and dead nodes need to
6898 * drop the binder_dead_nodes_lock before trying to take the node lock.
6899 */
6900 if (proc)
6901 binder_inner_proc_unlock(proc);
6902 else
6903 spin_unlock(&binder_dead_nodes_lock);
6904 if (prev_node)
6905 binder_put_node(prev_node);
6906 binder_node_inner_lock(node);
6907 print_binder_node_nilocked(m, node, hash_ptrs);
6908 binder_node_inner_unlock(node);
6909 if (proc)
6910 binder_inner_proc_lock(proc);
6911 else
6912 spin_lock(&binder_dead_nodes_lock);
6913 return node;
6914 }
6915
print_binder_proc(struct seq_file * m,struct binder_proc * proc,bool print_all,bool hash_ptrs)6916 static void print_binder_proc(struct seq_file *m, struct binder_proc *proc,
6917 bool print_all, bool hash_ptrs)
6918 {
6919 struct binder_work *w;
6920 struct rb_node *n;
6921 size_t start_pos = m->count;
6922 size_t header_pos;
6923 struct binder_node *last_node = NULL;
6924 struct list_head *special_list = NULL;
6925
6926 seq_printf(m, "proc %d\n", proc->pid);
6927 seq_printf(m, "context %s\n", proc->context->name);
6928 header_pos = m->count;
6929
6930 binder_inner_proc_lock(proc);
6931 for (n = rb_first(&proc->threads); n; n = rb_next(n))
6932 print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread,
6933 rb_node), print_all, hash_ptrs);
6934
6935 for (n = rb_first(&proc->nodes); n; n = rb_next(n)) {
6936 struct binder_node *node = rb_entry(n, struct binder_node,
6937 rb_node);
6938 if (!print_all && !node->has_async_transaction)
6939 continue;
6940
6941 last_node = print_next_binder_node_ilocked(m, proc, node,
6942 last_node,
6943 hash_ptrs);
6944 }
6945 binder_inner_proc_unlock(proc);
6946 if (last_node)
6947 binder_put_node(last_node);
6948
6949 if (print_all) {
6950 binder_proc_lock(proc);
6951 for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n))
6952 print_binder_ref_olocked(m, rb_entry(n,
6953 struct binder_ref,
6954 rb_node_desc));
6955 binder_proc_unlock(proc);
6956 }
6957 binder_alloc_print_allocated(m, &proc->alloc);
6958 binder_inner_proc_lock(proc);
6959 list_for_each_entry(w, &proc->todo, entry)
6960 print_binder_work_ilocked(m, proc, " ",
6961 " pending transaction", w,
6962 hash_ptrs);
6963 trace_android_vh_binder_check_special_work(proc, &special_list);
6964 if (special_list) {
6965 list_for_each_entry(w, special_list, entry)
6966 print_binder_work_ilocked(m, proc, " ",
6967 " special pending transaction", w,
6968 hash_ptrs);
6969 }
6970 list_for_each_entry(w, &proc->delivered_death, entry) {
6971 seq_puts(m, " has delivered dead binder\n");
6972 break;
6973 }
6974 list_for_each_entry(w, &proc->delivered_freeze, entry) {
6975 seq_puts(m, " has delivered freeze binder\n");
6976 break;
6977 }
6978 binder_inner_proc_unlock(proc);
6979 if (!print_all && m->count == header_pos)
6980 m->count = start_pos;
6981 }
6982
6983 static const char * const binder_return_strings[] = {
6984 "BR_ERROR",
6985 "BR_OK",
6986 "BR_TRANSACTION",
6987 "BR_REPLY",
6988 "BR_ACQUIRE_RESULT",
6989 "BR_DEAD_REPLY",
6990 "BR_TRANSACTION_COMPLETE",
6991 "BR_INCREFS",
6992 "BR_ACQUIRE",
6993 "BR_RELEASE",
6994 "BR_DECREFS",
6995 "BR_ATTEMPT_ACQUIRE",
6996 "BR_NOOP",
6997 "BR_SPAWN_LOOPER",
6998 "BR_FINISHED",
6999 "BR_DEAD_BINDER",
7000 "BR_CLEAR_DEATH_NOTIFICATION_DONE",
7001 "BR_FAILED_REPLY",
7002 "BR_FROZEN_REPLY",
7003 "BR_ONEWAY_SPAM_SUSPECT",
7004 "BR_TRANSACTION_PENDING_FROZEN",
7005 "BR_FROZEN_BINDER",
7006 "BR_CLEAR_FREEZE_NOTIFICATION_DONE",
7007 };
7008
7009 static const char * const binder_command_strings[] = {
7010 "BC_TRANSACTION",
7011 "BC_REPLY",
7012 "BC_ACQUIRE_RESULT",
7013 "BC_FREE_BUFFER",
7014 "BC_INCREFS",
7015 "BC_ACQUIRE",
7016 "BC_RELEASE",
7017 "BC_DECREFS",
7018 "BC_INCREFS_DONE",
7019 "BC_ACQUIRE_DONE",
7020 "BC_ATTEMPT_ACQUIRE",
7021 "BC_REGISTER_LOOPER",
7022 "BC_ENTER_LOOPER",
7023 "BC_EXIT_LOOPER",
7024 "BC_REQUEST_DEATH_NOTIFICATION",
7025 "BC_CLEAR_DEATH_NOTIFICATION",
7026 "BC_DEAD_BINDER_DONE",
7027 "BC_TRANSACTION_SG",
7028 "BC_REPLY_SG",
7029 "BC_REQUEST_FREEZE_NOTIFICATION",
7030 "BC_CLEAR_FREEZE_NOTIFICATION",
7031 "BC_FREEZE_NOTIFICATION_DONE",
7032 };
7033
7034 static const char * const binder_objstat_strings[] = {
7035 "proc",
7036 "thread",
7037 "node",
7038 "ref",
7039 "death",
7040 "transaction",
7041 "transaction_complete",
7042 "freeze",
7043 };
7044
print_binder_stats(struct seq_file * m,const char * prefix,struct binder_stats * stats)7045 static void print_binder_stats(struct seq_file *m, const char *prefix,
7046 struct binder_stats *stats)
7047 {
7048 int i;
7049
7050 BUILD_BUG_ON(ARRAY_SIZE(stats->bc) !=
7051 ARRAY_SIZE(binder_command_strings));
7052 for (i = 0; i < ARRAY_SIZE(stats->bc); i++) {
7053 int temp = atomic_read(&stats->bc[i]);
7054
7055 if (temp)
7056 seq_printf(m, "%s%s: %d\n", prefix,
7057 binder_command_strings[i], temp);
7058 }
7059
7060 BUILD_BUG_ON(ARRAY_SIZE(stats->br) !=
7061 ARRAY_SIZE(binder_return_strings));
7062 for (i = 0; i < ARRAY_SIZE(stats->br); i++) {
7063 int temp = atomic_read(&stats->br[i]);
7064
7065 if (temp)
7066 seq_printf(m, "%s%s: %d\n", prefix,
7067 binder_return_strings[i], temp);
7068 }
7069
7070 BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
7071 ARRAY_SIZE(binder_objstat_strings));
7072 BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
7073 ARRAY_SIZE(stats->obj_deleted));
7074 for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) {
7075 int created = atomic_read(&stats->obj_created[i]);
7076 int deleted = atomic_read(&stats->obj_deleted[i]);
7077
7078 if (created || deleted)
7079 seq_printf(m, "%s%s: active %d total %d\n",
7080 prefix,
7081 binder_objstat_strings[i],
7082 created - deleted,
7083 created);
7084 }
7085 }
7086
print_binder_proc_stats(struct seq_file * m,struct binder_proc * proc)7087 static void print_binder_proc_stats(struct seq_file *m,
7088 struct binder_proc *proc)
7089 {
7090 struct binder_work *w;
7091 struct binder_thread *thread;
7092 struct rb_node *n;
7093 int count, strong, weak, ready_threads;
7094 size_t free_async_space =
7095 binder_alloc_get_free_async_space(&proc->alloc);
7096
7097 seq_printf(m, "proc %d\n", proc->pid);
7098 seq_printf(m, "context %s\n", proc->context->name);
7099 count = 0;
7100 ready_threads = 0;
7101 binder_inner_proc_lock(proc);
7102 for (n = rb_first(&proc->threads); n; n = rb_next(n))
7103 count++;
7104
7105 list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node)
7106 ready_threads++;
7107
7108 seq_printf(m, " threads: %d\n", count);
7109 seq_printf(m, " requested threads: %d+%d/%d\n"
7110 " ready threads %d\n"
7111 " free async space %zd\n", proc->requested_threads,
7112 proc->requested_threads_started, proc->max_threads,
7113 ready_threads,
7114 free_async_space);
7115 count = 0;
7116 for (n = rb_first(&proc->nodes); n; n = rb_next(n))
7117 count++;
7118 binder_inner_proc_unlock(proc);
7119 seq_printf(m, " nodes: %d\n", count);
7120 count = 0;
7121 strong = 0;
7122 weak = 0;
7123 binder_proc_lock(proc);
7124 for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n)) {
7125 struct binder_ref *ref = rb_entry(n, struct binder_ref,
7126 rb_node_desc);
7127 count++;
7128 strong += ref->data.strong;
7129 weak += ref->data.weak;
7130 }
7131 binder_proc_unlock(proc);
7132 seq_printf(m, " refs: %d s %d w %d\n", count, strong, weak);
7133
7134 count = binder_alloc_get_allocated_count(&proc->alloc);
7135 seq_printf(m, " buffers: %d\n", count);
7136
7137 binder_alloc_print_pages(m, &proc->alloc);
7138
7139 count = 0;
7140 binder_inner_proc_lock(proc);
7141 list_for_each_entry(w, &proc->todo, entry) {
7142 if (w->type == BINDER_WORK_TRANSACTION)
7143 count++;
7144 }
7145 binder_inner_proc_unlock(proc);
7146 seq_printf(m, " pending transactions: %d\n", count);
7147
7148 print_binder_stats(m, " ", &proc->stats);
7149 }
7150
print_binder_state(struct seq_file * m,bool hash_ptrs)7151 static void print_binder_state(struct seq_file *m, bool hash_ptrs)
7152 {
7153 struct binder_proc *proc;
7154 struct binder_node *node;
7155 struct binder_node *last_node = NULL;
7156
7157 seq_puts(m, "binder state:\n");
7158
7159 spin_lock(&binder_dead_nodes_lock);
7160 if (!hlist_empty(&binder_dead_nodes))
7161 seq_puts(m, "dead nodes:\n");
7162 hlist_for_each_entry(node, &binder_dead_nodes, dead_node)
7163 last_node = print_next_binder_node_ilocked(m, NULL, node,
7164 last_node,
7165 hash_ptrs);
7166 spin_unlock(&binder_dead_nodes_lock);
7167 if (last_node)
7168 binder_put_node(last_node);
7169
7170 mutex_lock(&binder_procs_lock);
7171 hlist_for_each_entry(proc, &binder_procs, proc_node)
7172 print_binder_proc(m, proc, true, hash_ptrs);
7173 mutex_unlock(&binder_procs_lock);
7174 }
7175
print_binder_transactions(struct seq_file * m,bool hash_ptrs)7176 static void print_binder_transactions(struct seq_file *m, bool hash_ptrs)
7177 {
7178 struct binder_proc *proc;
7179
7180 seq_puts(m, "binder transactions:\n");
7181 mutex_lock(&binder_procs_lock);
7182 hlist_for_each_entry(proc, &binder_procs, proc_node)
7183 print_binder_proc(m, proc, false, hash_ptrs);
7184 mutex_unlock(&binder_procs_lock);
7185 }
7186
state_show(struct seq_file * m,void * unused)7187 static int state_show(struct seq_file *m, void *unused)
7188 {
7189 print_binder_state(m, false);
7190 return 0;
7191 }
7192
state_hashed_show(struct seq_file * m,void * unused)7193 static int state_hashed_show(struct seq_file *m, void *unused)
7194 {
7195 print_binder_state(m, true);
7196 return 0;
7197 }
7198
stats_show(struct seq_file * m,void * unused)7199 static int stats_show(struct seq_file *m, void *unused)
7200 {
7201 struct binder_proc *proc;
7202
7203 seq_puts(m, "binder stats:\n");
7204
7205 print_binder_stats(m, "", &binder_stats);
7206
7207 mutex_lock(&binder_procs_lock);
7208 hlist_for_each_entry(proc, &binder_procs, proc_node)
7209 print_binder_proc_stats(m, proc);
7210 mutex_unlock(&binder_procs_lock);
7211
7212 return 0;
7213 }
7214
transactions_show(struct seq_file * m,void * unused)7215 static int transactions_show(struct seq_file *m, void *unused)
7216 {
7217 print_binder_transactions(m, false);
7218 return 0;
7219 }
7220
transactions_hashed_show(struct seq_file * m,void * unused)7221 static int transactions_hashed_show(struct seq_file *m, void *unused)
7222 {
7223 print_binder_transactions(m, true);
7224 return 0;
7225 }
7226
proc_show(struct seq_file * m,void * unused)7227 static int proc_show(struct seq_file *m, void *unused)
7228 {
7229 struct binder_proc *itr;
7230 int pid = (unsigned long)m->private;
7231
7232 mutex_lock(&binder_procs_lock);
7233 hlist_for_each_entry(itr, &binder_procs, proc_node) {
7234 if (itr->pid == pid) {
7235 seq_puts(m, "binder proc state:\n");
7236 print_binder_proc(m, itr, true, false);
7237 }
7238 }
7239 mutex_unlock(&binder_procs_lock);
7240
7241 return 0;
7242 }
7243
print_binder_transaction_log_entry(struct seq_file * m,struct binder_transaction_log_entry * e)7244 static void print_binder_transaction_log_entry(struct seq_file *m,
7245 struct binder_transaction_log_entry *e)
7246 {
7247 int debug_id = READ_ONCE(e->debug_id_done);
7248 /*
7249 * read barrier to guarantee debug_id_done read before
7250 * we print the log values
7251 */
7252 smp_rmb();
7253 seq_printf(m,
7254 "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d",
7255 e->debug_id, (e->call_type == 2) ? "reply" :
7256 ((e->call_type == 1) ? "async" : "call "), e->from_proc,
7257 e->from_thread, e->to_proc, e->to_thread, e->context_name,
7258 e->to_node, e->target_handle, e->data_size, e->offsets_size,
7259 e->return_error, e->return_error_param,
7260 e->return_error_line);
7261 /*
7262 * read-barrier to guarantee read of debug_id_done after
7263 * done printing the fields of the entry
7264 */
7265 smp_rmb();
7266 seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ?
7267 "\n" : " (incomplete)\n");
7268 }
7269
transaction_log_show(struct seq_file * m,void * unused)7270 static int transaction_log_show(struct seq_file *m, void *unused)
7271 {
7272 struct binder_transaction_log *log = m->private;
7273 unsigned int log_cur = atomic_read(&log->cur);
7274 unsigned int count;
7275 unsigned int cur;
7276 int i;
7277
7278 count = log_cur + 1;
7279 cur = count < ARRAY_SIZE(log->entry) && !log->full ?
7280 0 : count % ARRAY_SIZE(log->entry);
7281 if (count > ARRAY_SIZE(log->entry) || log->full)
7282 count = ARRAY_SIZE(log->entry);
7283 for (i = 0; i < count; i++) {
7284 unsigned int index = cur++ % ARRAY_SIZE(log->entry);
7285
7286 print_binder_transaction_log_entry(m, &log->entry[index]);
7287 }
7288 return 0;
7289 }
7290
7291 const struct file_operations binder_fops = {
7292 .owner = THIS_MODULE,
7293 .poll = binder_poll,
7294 .unlocked_ioctl = binder_ioctl,
7295 .compat_ioctl = compat_ptr_ioctl,
7296 .mmap = binder_mmap,
7297 .open = binder_open,
7298 .flush = binder_flush,
7299 .release = binder_release,
7300 };
7301
7302 DEFINE_SHOW_ATTRIBUTE(state);
7303 DEFINE_SHOW_ATTRIBUTE(state_hashed);
7304 DEFINE_SHOW_ATTRIBUTE(stats);
7305 DEFINE_SHOW_ATTRIBUTE(transactions);
7306 DEFINE_SHOW_ATTRIBUTE(transactions_hashed);
7307 DEFINE_SHOW_ATTRIBUTE(transaction_log);
7308
7309 const struct binder_debugfs_entry binder_debugfs_entries[] = {
7310 {
7311 .name = "state",
7312 .mode = 0444,
7313 .fops = &state_fops,
7314 .data = NULL,
7315 },
7316 {
7317 .name = "state_hashed",
7318 .mode = 0444,
7319 .fops = &state_hashed_fops,
7320 .data = NULL,
7321 },
7322 {
7323 .name = "stats",
7324 .mode = 0444,
7325 .fops = &stats_fops,
7326 .data = NULL,
7327 },
7328 {
7329 .name = "transactions",
7330 .mode = 0444,
7331 .fops = &transactions_fops,
7332 .data = NULL,
7333 },
7334 {
7335 .name = "transactions_hashed",
7336 .mode = 0444,
7337 .fops = &transactions_hashed_fops,
7338 .data = NULL,
7339 },
7340 {
7341 .name = "transaction_log",
7342 .mode = 0444,
7343 .fops = &transaction_log_fops,
7344 .data = &binder_transaction_log,
7345 },
7346 {
7347 .name = "failed_transaction_log",
7348 .mode = 0444,
7349 .fops = &transaction_log_fops,
7350 .data = &binder_transaction_log_failed,
7351 },
7352 {} /* terminator */
7353 };
7354
init_binder_device(const char * name)7355 static int __init init_binder_device(const char *name)
7356 {
7357 int ret;
7358 struct binder_device *binder_device;
7359
7360 binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL);
7361 if (!binder_device)
7362 return -ENOMEM;
7363
7364 binder_device->miscdev.fops = &binder_fops;
7365 binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
7366 binder_device->miscdev.name = name;
7367
7368 refcount_set(&binder_device->ref, 1);
7369 binder_device->context.binder_context_mgr_uid = INVALID_UID;
7370 binder_device->context.name = name;
7371 mutex_init(&binder_device->context.context_mgr_node_lock);
7372
7373 ret = misc_register(&binder_device->miscdev);
7374 if (ret < 0) {
7375 kfree(binder_device);
7376 return ret;
7377 }
7378
7379 hlist_add_head(&binder_device->hlist, &binder_devices);
7380
7381 return ret;
7382 }
7383
binder_init(void)7384 static int __init binder_init(void)
7385 {
7386 int ret;
7387 char *device_name, *device_tmp;
7388 struct binder_device *device;
7389 struct hlist_node *tmp;
7390 char *device_names = NULL;
7391 const struct binder_debugfs_entry *db_entry;
7392
7393 ret = binder_alloc_shrinker_init();
7394 if (ret)
7395 return ret;
7396
7397 atomic_set(&binder_transaction_log.cur, ~0U);
7398 atomic_set(&binder_transaction_log_failed.cur, ~0U);
7399
7400 binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL);
7401
7402 binder_for_each_debugfs_entry(db_entry)
7403 debugfs_create_file(db_entry->name,
7404 db_entry->mode,
7405 binder_debugfs_dir_entry_root,
7406 db_entry->data,
7407 db_entry->fops);
7408
7409 binder_debugfs_dir_entry_proc = debugfs_create_dir("proc",
7410 binder_debugfs_dir_entry_root);
7411
7412 if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
7413 strcmp(binder_devices_param, "") != 0) {
7414 /*
7415 * Copy the module_parameter string, because we don't want to
7416 * tokenize it in-place.
7417 */
7418 device_names = kstrdup(binder_devices_param, GFP_KERNEL);
7419 if (!device_names) {
7420 ret = -ENOMEM;
7421 goto err_alloc_device_names_failed;
7422 }
7423
7424 device_tmp = device_names;
7425 while ((device_name = strsep(&device_tmp, ","))) {
7426 ret = init_binder_device(device_name);
7427 if (ret)
7428 goto err_init_binder_device_failed;
7429 }
7430 }
7431
7432 ret = genl_register_family(&binder_nl_family);
7433 if (ret)
7434 goto err_init_binder_device_failed;
7435
7436 ret = init_binderfs();
7437 if (ret)
7438 goto err_init_binderfs_failed;
7439
7440 return ret;
7441
7442 err_init_binderfs_failed:
7443 genl_unregister_family(&binder_nl_family);
7444
7445 err_init_binder_device_failed:
7446 hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) {
7447 misc_deregister(&device->miscdev);
7448 hlist_del(&device->hlist);
7449 kfree(device);
7450 }
7451
7452 kfree(device_names);
7453
7454 err_alloc_device_names_failed:
7455 debugfs_remove_recursive(binder_debugfs_dir_entry_root);
7456 binder_alloc_shrinker_exit();
7457
7458 return ret;
7459 }
7460
7461 device_initcall(binder_init);
7462
7463 int binder_use_rust;
7464 EXPORT_SYMBOL_GPL(binder_use_rust);
7465 int binder_loaded;
7466 EXPORT_SYMBOL_GPL(binder_loaded);
7467
7468 static DEFINE_MUTEX(binder_use_rust_lock);
7469
7470 /*
7471 * Called by Rust Binder to unload the C Binder driver.
7472 */
unload_binder(void)7473 int unload_binder(void)
7474 {
7475 int ret = 0;
7476
7477 if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS))
7478 return -EINVAL;
7479
7480 mutex_lock(&binder_use_rust_lock);
7481 if (binder_loaded || !binder_use_rust)
7482 ret = -EINVAL;
7483 else
7484 binder_loaded = true;
7485 mutex_unlock(&binder_use_rust_lock);
7486
7487 if (!ret) {
7488 unload_binderfs();
7489 debugfs_remove_recursive(binder_debugfs_dir_entry_root);
7490 binder_alloc_shrinker_exit();
7491 }
7492
7493 return ret;
7494 }
7495 EXPORT_SYMBOL_GPL(unload_binder);
7496
on_binderfs_mount(void)7497 int on_binderfs_mount(void)
7498 {
7499 int ret = 0;
7500
7501 mutex_lock(&binder_use_rust_lock);
7502
7503 if (binder_loaded && binder_use_rust) {
7504 ret = -EINVAL;
7505 goto out;
7506 }
7507
7508 /*
7509 * C binder was mounted before loading the Rust Binder module. In this
7510 * case, we fall back to using C Binder even if Rust Binder was
7511 * requested.
7512 */
7513 if (binder_use_rust)
7514 pr_warn("Using C Binder even though binder.impl=rust is set.\n");
7515
7516 binder_use_rust = false;
7517 binder_loaded = true;
7518
7519 out:
7520 mutex_unlock(&binder_use_rust_lock);
7521 return ret;
7522 }
7523
binder_impl_param_set(const char * buffer,const struct kernel_param * kp)7524 static int binder_impl_param_set(const char *buffer, const struct kernel_param *kp)
7525 {
7526 int ret = 0;
7527
7528 mutex_lock(&binder_use_rust_lock);
7529
7530 if (binder_loaded) {
7531 ret = -EPERM;
7532 goto out;
7533 }
7534
7535 if (!strcmp(buffer, "rust"))
7536 binder_use_rust = true;
7537 else if (!strcmp(buffer, "c"))
7538 binder_use_rust = false;
7539 else
7540 ret = -EINVAL;
7541
7542 out:
7543 mutex_unlock(&binder_use_rust_lock);
7544 return ret;
7545 }
7546
binder_impl_param_get(char * buffer,const struct kernel_param * kp)7547 static int binder_impl_param_get(char *buffer, const struct kernel_param *kp)
7548 {
7549 /* The buffer is 4k bytes, so this will not overflow. */
7550 return sprintf(buffer, "%s\n", binder_use_rust ? "rust" : "c");
7551 }
7552
7553 static const struct kernel_param_ops binder_impl_param_ops = {
7554 .set = binder_impl_param_set,
7555 .get = binder_impl_param_get,
7556 };
7557
7558 module_param_cb(impl, &binder_impl_param_ops, NULL, 0644);
7559
7560 #define CREATE_TRACE_POINTS
7561 #include "binder_trace.h"
7562 EXPORT_TRACEPOINT_SYMBOL_GPL(binder_transaction_received);
7563
7564 MODULE_LICENSE("GPL v2");
7565