1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3 */
4 #include <linux/bpf.h>
5 #include <linux/bpf_trace.h>
6 #include <linux/bpf_lirc.h>
7 #include <linux/btf.h>
8 #include <linux/syscalls.h>
9 #include <linux/slab.h>
10 #include <linux/sched/signal.h>
11 #include <linux/vmalloc.h>
12 #include <linux/mmzone.h>
13 #include <linux/anon_inodes.h>
14 #include <linux/fdtable.h>
15 #include <linux/file.h>
16 #include <linux/fs.h>
17 #include <linux/license.h>
18 #include <linux/filter.h>
19 #include <linux/version.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/cred.h>
23 #include <linux/timekeeping.h>
24 #include <linux/ctype.h>
25 #include <linux/nospec.h>
26
27 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
28 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
29 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
30 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
31 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
32 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
33
34 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
35
36 DEFINE_PER_CPU(int, bpf_prog_active);
37 static DEFINE_IDR(prog_idr);
38 static DEFINE_SPINLOCK(prog_idr_lock);
39 static DEFINE_IDR(map_idr);
40 static DEFINE_SPINLOCK(map_idr_lock);
41
42 int sysctl_unprivileged_bpf_disabled __read_mostly =
43 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
44
45 static const struct bpf_map_ops * const bpf_map_types[] = {
46 #define BPF_PROG_TYPE(_id, _ops)
47 #define BPF_MAP_TYPE(_id, _ops) \
48 [_id] = &_ops,
49 #include <linux/bpf_types.h>
50 #undef BPF_PROG_TYPE
51 #undef BPF_MAP_TYPE
52 };
53
54 /*
55 * If we're handed a bigger struct than we know of, ensure all the unknown bits
56 * are 0 - i.e. new user-space does not rely on any kernel feature extensions
57 * we don't know about yet.
58 *
59 * There is a ToCToU between this function call and the following
60 * copy_from_user() call. However, this is not a concern since this function is
61 * meant to be a future-proofing of bits.
62 */
bpf_check_uarg_tail_zero(void __user * uaddr,size_t expected_size,size_t actual_size)63 int bpf_check_uarg_tail_zero(void __user *uaddr,
64 size_t expected_size,
65 size_t actual_size)
66 {
67 unsigned char __user *addr;
68 unsigned char __user *end;
69 unsigned char val;
70 int err;
71
72 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
73 return -E2BIG;
74
75 if (unlikely(!access_ok(uaddr, actual_size)))
76 return -EFAULT;
77
78 if (actual_size <= expected_size)
79 return 0;
80
81 addr = uaddr + expected_size;
82 end = uaddr + actual_size;
83
84 for (; addr < end; addr++) {
85 err = get_user(val, addr);
86 if (err)
87 return err;
88 if (val)
89 return -E2BIG;
90 }
91
92 return 0;
93 }
94
95 const struct bpf_map_ops bpf_map_offload_ops = {
96 .map_alloc = bpf_map_offload_map_alloc,
97 .map_free = bpf_map_offload_map_free,
98 .map_check_btf = map_check_no_btf,
99 };
100
find_and_alloc_map(union bpf_attr * attr)101 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
102 {
103 const struct bpf_map_ops *ops;
104 u32 type = attr->map_type;
105 struct bpf_map *map;
106 int err;
107
108 if (type >= ARRAY_SIZE(bpf_map_types))
109 return ERR_PTR(-EINVAL);
110 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
111 ops = bpf_map_types[type];
112 if (!ops)
113 return ERR_PTR(-EINVAL);
114
115 if (ops->map_alloc_check) {
116 err = ops->map_alloc_check(attr);
117 if (err)
118 return ERR_PTR(err);
119 }
120 if (attr->map_ifindex)
121 ops = &bpf_map_offload_ops;
122 map = ops->map_alloc(attr);
123 if (IS_ERR(map))
124 return map;
125 map->ops = ops;
126 map->map_type = type;
127 return map;
128 }
129
bpf_map_area_alloc(u64 size,int numa_node)130 void *bpf_map_area_alloc(u64 size, int numa_node)
131 {
132 /* We really just want to fail instead of triggering OOM killer
133 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
134 * which is used for lower order allocation requests.
135 *
136 * It has been observed that higher order allocation requests done by
137 * vmalloc with __GFP_NORETRY being set might fail due to not trying
138 * to reclaim memory from the page cache, thus we set
139 * __GFP_RETRY_MAYFAIL to avoid such situations.
140 */
141
142 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
143 void *area;
144
145 if (size >= SIZE_MAX)
146 return NULL;
147
148 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
149 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
150 numa_node);
151 if (area != NULL)
152 return area;
153 }
154
155 return __vmalloc_node_flags_caller(size, numa_node,
156 GFP_KERNEL | __GFP_RETRY_MAYFAIL |
157 flags, __builtin_return_address(0));
158 }
159
bpf_map_area_free(void * area)160 void bpf_map_area_free(void *area)
161 {
162 kvfree(area);
163 }
164
bpf_map_flags_retain_permanent(u32 flags)165 static u32 bpf_map_flags_retain_permanent(u32 flags)
166 {
167 /* Some map creation flags are not tied to the map object but
168 * rather to the map fd instead, so they have no meaning upon
169 * map object inspection since multiple file descriptors with
170 * different (access) properties can exist here. Thus, given
171 * this has zero meaning for the map itself, lets clear these
172 * from here.
173 */
174 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
175 }
176
bpf_map_init_from_attr(struct bpf_map * map,union bpf_attr * attr)177 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
178 {
179 map->map_type = attr->map_type;
180 map->key_size = attr->key_size;
181 map->value_size = attr->value_size;
182 map->max_entries = attr->max_entries;
183 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
184 map->numa_node = bpf_map_attr_numa_node(attr);
185 }
186
bpf_charge_memlock(struct user_struct * user,u32 pages)187 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
188 {
189 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
190
191 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
192 atomic_long_sub(pages, &user->locked_vm);
193 return -EPERM;
194 }
195 return 0;
196 }
197
bpf_uncharge_memlock(struct user_struct * user,u32 pages)198 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
199 {
200 if (user)
201 atomic_long_sub(pages, &user->locked_vm);
202 }
203
bpf_map_charge_init(struct bpf_map_memory * mem,u64 size)204 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
205 {
206 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
207 struct user_struct *user;
208 int ret;
209
210 if (size >= U32_MAX - PAGE_SIZE)
211 return -E2BIG;
212
213 user = get_current_user();
214 ret = bpf_charge_memlock(user, pages);
215 if (ret) {
216 free_uid(user);
217 return ret;
218 }
219
220 mem->pages = pages;
221 mem->user = user;
222
223 return 0;
224 }
225
bpf_map_charge_finish(struct bpf_map_memory * mem)226 void bpf_map_charge_finish(struct bpf_map_memory *mem)
227 {
228 bpf_uncharge_memlock(mem->user, mem->pages);
229 free_uid(mem->user);
230 }
231
bpf_map_charge_move(struct bpf_map_memory * dst,struct bpf_map_memory * src)232 void bpf_map_charge_move(struct bpf_map_memory *dst,
233 struct bpf_map_memory *src)
234 {
235 *dst = *src;
236
237 /* Make sure src will not be used for the redundant uncharging. */
238 memset(src, 0, sizeof(struct bpf_map_memory));
239 }
240
bpf_map_charge_memlock(struct bpf_map * map,u32 pages)241 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
242 {
243 int ret;
244
245 ret = bpf_charge_memlock(map->memory.user, pages);
246 if (ret)
247 return ret;
248 map->memory.pages += pages;
249 return ret;
250 }
251
bpf_map_uncharge_memlock(struct bpf_map * map,u32 pages)252 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
253 {
254 bpf_uncharge_memlock(map->memory.user, pages);
255 map->memory.pages -= pages;
256 }
257
bpf_map_alloc_id(struct bpf_map * map)258 static int bpf_map_alloc_id(struct bpf_map *map)
259 {
260 int id;
261
262 idr_preload(GFP_KERNEL);
263 spin_lock_bh(&map_idr_lock);
264 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
265 if (id > 0)
266 map->id = id;
267 spin_unlock_bh(&map_idr_lock);
268 idr_preload_end();
269
270 if (WARN_ON_ONCE(!id))
271 return -ENOSPC;
272
273 return id > 0 ? 0 : id;
274 }
275
bpf_map_free_id(struct bpf_map * map,bool do_idr_lock)276 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
277 {
278 unsigned long flags;
279
280 /* Offloaded maps are removed from the IDR store when their device
281 * disappears - even if someone holds an fd to them they are unusable,
282 * the memory is gone, all ops will fail; they are simply waiting for
283 * refcnt to drop to be freed.
284 */
285 if (!map->id)
286 return;
287
288 if (do_idr_lock)
289 spin_lock_irqsave(&map_idr_lock, flags);
290 else
291 __acquire(&map_idr_lock);
292
293 idr_remove(&map_idr, map->id);
294 map->id = 0;
295
296 if (do_idr_lock)
297 spin_unlock_irqrestore(&map_idr_lock, flags);
298 else
299 __release(&map_idr_lock);
300 }
301
302 /* called from workqueue */
bpf_map_free_deferred(struct work_struct * work)303 static void bpf_map_free_deferred(struct work_struct *work)
304 {
305 struct bpf_map *map = container_of(work, struct bpf_map, work);
306 struct bpf_map_memory mem;
307
308 bpf_map_charge_move(&mem, &map->memory);
309 security_bpf_map_free(map);
310 /* implementation dependent freeing */
311 map->ops->map_free(map);
312 bpf_map_charge_finish(&mem);
313 }
314
bpf_map_put_uref(struct bpf_map * map)315 static void bpf_map_put_uref(struct bpf_map *map)
316 {
317 if (atomic_dec_and_test(&map->usercnt)) {
318 if (map->ops->map_release_uref)
319 map->ops->map_release_uref(map);
320 }
321 }
322
323 /* decrement map refcnt and schedule it for freeing via workqueue
324 * (unrelying map implementation ops->map_free() might sleep)
325 */
__bpf_map_put(struct bpf_map * map,bool do_idr_lock)326 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
327 {
328 if (atomic_dec_and_test(&map->refcnt)) {
329 /* bpf_map_free_id() must be called first */
330 bpf_map_free_id(map, do_idr_lock);
331 btf_put(map->btf);
332 INIT_WORK(&map->work, bpf_map_free_deferred);
333 schedule_work(&map->work);
334 }
335 }
336
bpf_map_put(struct bpf_map * map)337 void bpf_map_put(struct bpf_map *map)
338 {
339 __bpf_map_put(map, true);
340 }
341 EXPORT_SYMBOL_GPL(bpf_map_put);
342
bpf_map_put_with_uref(struct bpf_map * map)343 void bpf_map_put_with_uref(struct bpf_map *map)
344 {
345 bpf_map_put_uref(map);
346 bpf_map_put(map);
347 }
348
bpf_map_release(struct inode * inode,struct file * filp)349 static int bpf_map_release(struct inode *inode, struct file *filp)
350 {
351 struct bpf_map *map = filp->private_data;
352
353 if (map->ops->map_release)
354 map->ops->map_release(map, filp);
355
356 bpf_map_put_with_uref(map);
357 return 0;
358 }
359
map_get_sys_perms(struct bpf_map * map,struct fd f)360 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
361 {
362 fmode_t mode = f.file->f_mode;
363
364 /* Our file permissions may have been overridden by global
365 * map permissions facing syscall side.
366 */
367 if (READ_ONCE(map->frozen))
368 mode &= ~FMODE_CAN_WRITE;
369 return mode;
370 }
371
372 #ifdef CONFIG_PROC_FS
bpf_map_show_fdinfo(struct seq_file * m,struct file * filp)373 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
374 {
375 const struct bpf_map *map = filp->private_data;
376 const struct bpf_array *array;
377 u32 owner_prog_type = 0;
378 u32 owner_jited = 0;
379
380 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
381 array = container_of(map, struct bpf_array, map);
382 owner_prog_type = array->owner_prog_type;
383 owner_jited = array->owner_jited;
384 }
385
386 seq_printf(m,
387 "map_type:\t%u\n"
388 "key_size:\t%u\n"
389 "value_size:\t%u\n"
390 "max_entries:\t%u\n"
391 "map_flags:\t%#x\n"
392 "memlock:\t%llu\n"
393 "map_id:\t%u\n"
394 "frozen:\t%u\n",
395 map->map_type,
396 map->key_size,
397 map->value_size,
398 map->max_entries,
399 map->map_flags,
400 map->memory.pages * 1ULL << PAGE_SHIFT,
401 map->id,
402 READ_ONCE(map->frozen));
403
404 if (owner_prog_type) {
405 seq_printf(m, "owner_prog_type:\t%u\n",
406 owner_prog_type);
407 seq_printf(m, "owner_jited:\t%u\n",
408 owner_jited);
409 }
410 }
411 #endif
412
bpf_dummy_read(struct file * filp,char __user * buf,size_t siz,loff_t * ppos)413 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
414 loff_t *ppos)
415 {
416 /* We need this handler such that alloc_file() enables
417 * f_mode with FMODE_CAN_READ.
418 */
419 return -EINVAL;
420 }
421
bpf_dummy_write(struct file * filp,const char __user * buf,size_t siz,loff_t * ppos)422 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
423 size_t siz, loff_t *ppos)
424 {
425 /* We need this handler such that alloc_file() enables
426 * f_mode with FMODE_CAN_WRITE.
427 */
428 return -EINVAL;
429 }
430
431 const struct file_operations bpf_map_fops = {
432 #ifdef CONFIG_PROC_FS
433 .show_fdinfo = bpf_map_show_fdinfo,
434 #endif
435 .release = bpf_map_release,
436 .read = bpf_dummy_read,
437 .write = bpf_dummy_write,
438 };
439
bpf_map_new_fd(struct bpf_map * map,int flags)440 int bpf_map_new_fd(struct bpf_map *map, int flags)
441 {
442 int ret;
443
444 ret = security_bpf_map(map, OPEN_FMODE(flags));
445 if (ret < 0)
446 return ret;
447
448 return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
449 flags | O_CLOEXEC);
450 }
451
bpf_get_file_flag(int flags)452 int bpf_get_file_flag(int flags)
453 {
454 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
455 return -EINVAL;
456 if (flags & BPF_F_RDONLY)
457 return O_RDONLY;
458 if (flags & BPF_F_WRONLY)
459 return O_WRONLY;
460 return O_RDWR;
461 }
462
463 /* helper macro to check that unused fields 'union bpf_attr' are zero */
464 #define CHECK_ATTR(CMD) \
465 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
466 sizeof(attr->CMD##_LAST_FIELD), 0, \
467 sizeof(*attr) - \
468 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
469 sizeof(attr->CMD##_LAST_FIELD)) != NULL
470
471 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
472 * Return 0 on success and < 0 on error.
473 */
bpf_obj_name_cpy(char * dst,const char * src)474 static int bpf_obj_name_cpy(char *dst, const char *src)
475 {
476 const char *end = src + BPF_OBJ_NAME_LEN;
477
478 memset(dst, 0, BPF_OBJ_NAME_LEN);
479 /* Copy all isalnum(), '_' and '.' chars. */
480 while (src < end && *src) {
481 if (!isalnum(*src) &&
482 *src != '_' && *src != '.')
483 return -EINVAL;
484 *dst++ = *src++;
485 }
486
487 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
488 if (src == end)
489 return -EINVAL;
490
491 return 0;
492 }
493
map_check_no_btf(const struct bpf_map * map,const struct btf * btf,const struct btf_type * key_type,const struct btf_type * value_type)494 int map_check_no_btf(const struct bpf_map *map,
495 const struct btf *btf,
496 const struct btf_type *key_type,
497 const struct btf_type *value_type)
498 {
499 return -ENOTSUPP;
500 }
501
map_check_btf(struct bpf_map * map,const struct btf * btf,u32 btf_key_id,u32 btf_value_id)502 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
503 u32 btf_key_id, u32 btf_value_id)
504 {
505 const struct btf_type *key_type, *value_type;
506 u32 key_size, value_size;
507 int ret = 0;
508
509 /* Some maps allow key to be unspecified. */
510 if (btf_key_id) {
511 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
512 if (!key_type || key_size != map->key_size)
513 return -EINVAL;
514 } else {
515 key_type = btf_type_by_id(btf, 0);
516 if (!map->ops->map_check_btf)
517 return -EINVAL;
518 }
519
520 value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
521 if (!value_type || value_size != map->value_size)
522 return -EINVAL;
523
524 map->spin_lock_off = btf_find_spin_lock(btf, value_type);
525
526 if (map_value_has_spin_lock(map)) {
527 if (map->map_flags & BPF_F_RDONLY_PROG)
528 return -EACCES;
529 if (map->map_type != BPF_MAP_TYPE_HASH &&
530 map->map_type != BPF_MAP_TYPE_ARRAY &&
531 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
532 map->map_type != BPF_MAP_TYPE_SK_STORAGE)
533 return -ENOTSUPP;
534 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
535 map->value_size) {
536 WARN_ONCE(1,
537 "verifier bug spin_lock_off %d value_size %d\n",
538 map->spin_lock_off, map->value_size);
539 return -EFAULT;
540 }
541 }
542
543 if (map->ops->map_check_btf)
544 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
545
546 return ret;
547 }
548
549 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
550 /* called via syscall */
map_create(union bpf_attr * attr)551 static int map_create(union bpf_attr *attr)
552 {
553 int numa_node = bpf_map_attr_numa_node(attr);
554 struct bpf_map_memory mem;
555 struct bpf_map *map;
556 int f_flags;
557 int err;
558
559 err = CHECK_ATTR(BPF_MAP_CREATE);
560 if (err)
561 return -EINVAL;
562
563 f_flags = bpf_get_file_flag(attr->map_flags);
564 if (f_flags < 0)
565 return f_flags;
566
567 if (numa_node != NUMA_NO_NODE &&
568 ((unsigned int)numa_node >= nr_node_ids ||
569 !node_online(numa_node)))
570 return -EINVAL;
571
572 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
573 map = find_and_alloc_map(attr);
574 if (IS_ERR(map))
575 return PTR_ERR(map);
576
577 err = bpf_obj_name_cpy(map->name, attr->map_name);
578 if (err)
579 goto free_map;
580
581 atomic_set(&map->refcnt, 1);
582 atomic_set(&map->usercnt, 1);
583
584 if (attr->btf_key_type_id || attr->btf_value_type_id) {
585 struct btf *btf;
586
587 if (!attr->btf_value_type_id) {
588 err = -EINVAL;
589 goto free_map;
590 }
591
592 btf = btf_get_by_fd(attr->btf_fd);
593 if (IS_ERR(btf)) {
594 err = PTR_ERR(btf);
595 goto free_map;
596 }
597
598 err = map_check_btf(map, btf, attr->btf_key_type_id,
599 attr->btf_value_type_id);
600 if (err) {
601 btf_put(btf);
602 goto free_map;
603 }
604
605 map->btf = btf;
606 map->btf_key_type_id = attr->btf_key_type_id;
607 map->btf_value_type_id = attr->btf_value_type_id;
608 } else {
609 map->spin_lock_off = -EINVAL;
610 }
611
612 err = security_bpf_map_alloc(map);
613 if (err)
614 goto free_map;
615
616 err = bpf_map_alloc_id(map);
617 if (err)
618 goto free_map_sec;
619
620 err = bpf_map_new_fd(map, f_flags);
621 if (err < 0) {
622 /* failed to allocate fd.
623 * bpf_map_put_with_uref() is needed because the above
624 * bpf_map_alloc_id() has published the map
625 * to the userspace and the userspace may
626 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
627 */
628 bpf_map_put_with_uref(map);
629 return err;
630 }
631
632 return err;
633
634 free_map_sec:
635 security_bpf_map_free(map);
636 free_map:
637 btf_put(map->btf);
638 bpf_map_charge_move(&mem, &map->memory);
639 map->ops->map_free(map);
640 bpf_map_charge_finish(&mem);
641 return err;
642 }
643
644 /* if error is returned, fd is released.
645 * On success caller should complete fd access with matching fdput()
646 */
__bpf_map_get(struct fd f)647 struct bpf_map *__bpf_map_get(struct fd f)
648 {
649 if (!f.file)
650 return ERR_PTR(-EBADF);
651 if (f.file->f_op != &bpf_map_fops) {
652 fdput(f);
653 return ERR_PTR(-EINVAL);
654 }
655
656 return f.file->private_data;
657 }
658
659 /* prog's and map's refcnt limit */
660 #define BPF_MAX_REFCNT 32768
661
bpf_map_inc(struct bpf_map * map,bool uref)662 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
663 {
664 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
665 atomic_dec(&map->refcnt);
666 return ERR_PTR(-EBUSY);
667 }
668 if (uref)
669 atomic_inc(&map->usercnt);
670 return map;
671 }
672 EXPORT_SYMBOL_GPL(bpf_map_inc);
673
bpf_map_get_with_uref(u32 ufd)674 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
675 {
676 struct fd f = fdget(ufd);
677 struct bpf_map *map;
678
679 map = __bpf_map_get(f);
680 if (IS_ERR(map))
681 return map;
682
683 map = bpf_map_inc(map, true);
684 fdput(f);
685
686 return map;
687 }
688
689 /* map_idr_lock should have been held */
__bpf_map_inc_not_zero(struct bpf_map * map,bool uref)690 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map,
691 bool uref)
692 {
693 int refold;
694
695 refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
696
697 if (refold >= BPF_MAX_REFCNT) {
698 __bpf_map_put(map, false);
699 return ERR_PTR(-EBUSY);
700 }
701
702 if (!refold)
703 return ERR_PTR(-ENOENT);
704
705 if (uref)
706 atomic_inc(&map->usercnt);
707
708 return map;
709 }
710
bpf_map_inc_not_zero(struct bpf_map * map,bool uref)711 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
712 {
713 spin_lock_bh(&map_idr_lock);
714 map = __bpf_map_inc_not_zero(map, uref);
715 spin_unlock_bh(&map_idr_lock);
716
717 return map;
718 }
719 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
720
bpf_stackmap_copy(struct bpf_map * map,void * key,void * value)721 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
722 {
723 return -ENOTSUPP;
724 }
725
__bpf_copy_key(void __user * ukey,u64 key_size)726 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
727 {
728 if (key_size)
729 return memdup_user(ukey, key_size);
730
731 if (ukey)
732 return ERR_PTR(-EINVAL);
733
734 return NULL;
735 }
736
737 /* last field in 'union bpf_attr' used by this command */
738 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
739
map_lookup_elem(union bpf_attr * attr)740 static int map_lookup_elem(union bpf_attr *attr)
741 {
742 void __user *ukey = u64_to_user_ptr(attr->key);
743 void __user *uvalue = u64_to_user_ptr(attr->value);
744 int ufd = attr->map_fd;
745 struct bpf_map *map;
746 void *key, *value, *ptr;
747 u32 value_size;
748 struct fd f;
749 int err;
750
751 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
752 return -EINVAL;
753
754 if (attr->flags & ~BPF_F_LOCK)
755 return -EINVAL;
756
757 f = fdget(ufd);
758 map = __bpf_map_get(f);
759 if (IS_ERR(map))
760 return PTR_ERR(map);
761 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
762 err = -EPERM;
763 goto err_put;
764 }
765
766 if ((attr->flags & BPF_F_LOCK) &&
767 !map_value_has_spin_lock(map)) {
768 err = -EINVAL;
769 goto err_put;
770 }
771
772 key = __bpf_copy_key(ukey, map->key_size);
773 if (IS_ERR(key)) {
774 err = PTR_ERR(key);
775 goto err_put;
776 }
777
778 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
779 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
780 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
781 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
782 value_size = round_up(map->value_size, 8) * num_possible_cpus();
783 else if (IS_FD_MAP(map))
784 value_size = sizeof(u32);
785 else
786 value_size = map->value_size;
787
788 err = -ENOMEM;
789 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
790 if (!value)
791 goto free_key;
792
793 if (bpf_map_is_dev_bound(map)) {
794 err = bpf_map_offload_lookup_elem(map, key, value);
795 goto done;
796 }
797
798 preempt_disable();
799 this_cpu_inc(bpf_prog_active);
800 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
801 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
802 err = bpf_percpu_hash_copy(map, key, value);
803 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
804 err = bpf_percpu_array_copy(map, key, value);
805 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
806 err = bpf_percpu_cgroup_storage_copy(map, key, value);
807 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
808 err = bpf_stackmap_copy(map, key, value);
809 } else if (IS_FD_ARRAY(map)) {
810 err = bpf_fd_array_map_lookup_elem(map, key, value);
811 } else if (IS_FD_HASH(map)) {
812 err = bpf_fd_htab_map_lookup_elem(map, key, value);
813 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
814 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
815 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
816 map->map_type == BPF_MAP_TYPE_STACK) {
817 err = map->ops->map_peek_elem(map, value);
818 } else {
819 rcu_read_lock();
820 if (map->ops->map_lookup_elem_sys_only)
821 ptr = map->ops->map_lookup_elem_sys_only(map, key);
822 else
823 ptr = map->ops->map_lookup_elem(map, key);
824 if (IS_ERR(ptr)) {
825 err = PTR_ERR(ptr);
826 } else if (!ptr) {
827 err = -ENOENT;
828 } else {
829 err = 0;
830 if (attr->flags & BPF_F_LOCK)
831 /* lock 'ptr' and copy everything but lock */
832 copy_map_value_locked(map, value, ptr, true);
833 else
834 copy_map_value(map, value, ptr);
835 /* mask lock, since value wasn't zero inited */
836 check_and_init_map_lock(map, value);
837 }
838 rcu_read_unlock();
839 }
840 this_cpu_dec(bpf_prog_active);
841 preempt_enable();
842
843 done:
844 if (err)
845 goto free_value;
846
847 err = -EFAULT;
848 if (copy_to_user(uvalue, value, value_size) != 0)
849 goto free_value;
850
851 err = 0;
852
853 free_value:
854 kfree(value);
855 free_key:
856 kfree(key);
857 err_put:
858 fdput(f);
859 return err;
860 }
861
maybe_wait_bpf_programs(struct bpf_map * map)862 static void maybe_wait_bpf_programs(struct bpf_map *map)
863 {
864 /* Wait for any running BPF programs to complete so that
865 * userspace, when we return to it, knows that all programs
866 * that could be running use the new map value.
867 */
868 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
869 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
870 synchronize_rcu();
871 }
872
873 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
874
map_update_elem(union bpf_attr * attr)875 static int map_update_elem(union bpf_attr *attr)
876 {
877 void __user *ukey = u64_to_user_ptr(attr->key);
878 void __user *uvalue = u64_to_user_ptr(attr->value);
879 int ufd = attr->map_fd;
880 struct bpf_map *map;
881 void *key, *value;
882 u32 value_size;
883 struct fd f;
884 int err;
885
886 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
887 return -EINVAL;
888
889 f = fdget(ufd);
890 map = __bpf_map_get(f);
891 if (IS_ERR(map))
892 return PTR_ERR(map);
893 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
894 err = -EPERM;
895 goto err_put;
896 }
897
898 if ((attr->flags & BPF_F_LOCK) &&
899 !map_value_has_spin_lock(map)) {
900 err = -EINVAL;
901 goto err_put;
902 }
903
904 key = __bpf_copy_key(ukey, map->key_size);
905 if (IS_ERR(key)) {
906 err = PTR_ERR(key);
907 goto err_put;
908 }
909
910 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
911 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
912 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
913 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
914 value_size = round_up(map->value_size, 8) * num_possible_cpus();
915 else
916 value_size = map->value_size;
917
918 err = -ENOMEM;
919 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
920 if (!value)
921 goto free_key;
922
923 err = -EFAULT;
924 if (copy_from_user(value, uvalue, value_size) != 0)
925 goto free_value;
926
927 /* Need to create a kthread, thus must support schedule */
928 if (bpf_map_is_dev_bound(map)) {
929 err = bpf_map_offload_update_elem(map, key, value, attr->flags);
930 goto out;
931 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
932 map->map_type == BPF_MAP_TYPE_SOCKHASH ||
933 map->map_type == BPF_MAP_TYPE_SOCKMAP) {
934 err = map->ops->map_update_elem(map, key, value, attr->flags);
935 goto out;
936 }
937
938 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
939 * inside bpf map update or delete otherwise deadlocks are possible
940 */
941 preempt_disable();
942 __this_cpu_inc(bpf_prog_active);
943 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
944 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
945 err = bpf_percpu_hash_update(map, key, value, attr->flags);
946 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
947 err = bpf_percpu_array_update(map, key, value, attr->flags);
948 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
949 err = bpf_percpu_cgroup_storage_update(map, key, value,
950 attr->flags);
951 } else if (IS_FD_ARRAY(map)) {
952 rcu_read_lock();
953 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
954 attr->flags);
955 rcu_read_unlock();
956 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
957 rcu_read_lock();
958 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
959 attr->flags);
960 rcu_read_unlock();
961 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
962 /* rcu_read_lock() is not needed */
963 err = bpf_fd_reuseport_array_update_elem(map, key, value,
964 attr->flags);
965 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
966 map->map_type == BPF_MAP_TYPE_STACK) {
967 err = map->ops->map_push_elem(map, value, attr->flags);
968 } else {
969 rcu_read_lock();
970 err = map->ops->map_update_elem(map, key, value, attr->flags);
971 rcu_read_unlock();
972 }
973 __this_cpu_dec(bpf_prog_active);
974 preempt_enable();
975 maybe_wait_bpf_programs(map);
976 out:
977 free_value:
978 kfree(value);
979 free_key:
980 kfree(key);
981 err_put:
982 fdput(f);
983 return err;
984 }
985
986 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
987
map_delete_elem(union bpf_attr * attr)988 static int map_delete_elem(union bpf_attr *attr)
989 {
990 void __user *ukey = u64_to_user_ptr(attr->key);
991 int ufd = attr->map_fd;
992 struct bpf_map *map;
993 struct fd f;
994 void *key;
995 int err;
996
997 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
998 return -EINVAL;
999
1000 f = fdget(ufd);
1001 map = __bpf_map_get(f);
1002 if (IS_ERR(map))
1003 return PTR_ERR(map);
1004 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1005 err = -EPERM;
1006 goto err_put;
1007 }
1008
1009 key = __bpf_copy_key(ukey, map->key_size);
1010 if (IS_ERR(key)) {
1011 err = PTR_ERR(key);
1012 goto err_put;
1013 }
1014
1015 if (bpf_map_is_dev_bound(map)) {
1016 err = bpf_map_offload_delete_elem(map, key);
1017 goto out;
1018 }
1019
1020 preempt_disable();
1021 __this_cpu_inc(bpf_prog_active);
1022 rcu_read_lock();
1023 err = map->ops->map_delete_elem(map, key);
1024 rcu_read_unlock();
1025 __this_cpu_dec(bpf_prog_active);
1026 preempt_enable();
1027 maybe_wait_bpf_programs(map);
1028 out:
1029 kfree(key);
1030 err_put:
1031 fdput(f);
1032 return err;
1033 }
1034
1035 /* last field in 'union bpf_attr' used by this command */
1036 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1037
map_get_next_key(union bpf_attr * attr)1038 static int map_get_next_key(union bpf_attr *attr)
1039 {
1040 void __user *ukey = u64_to_user_ptr(attr->key);
1041 void __user *unext_key = u64_to_user_ptr(attr->next_key);
1042 int ufd = attr->map_fd;
1043 struct bpf_map *map;
1044 void *key, *next_key;
1045 struct fd f;
1046 int err;
1047
1048 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1049 return -EINVAL;
1050
1051 f = fdget(ufd);
1052 map = __bpf_map_get(f);
1053 if (IS_ERR(map))
1054 return PTR_ERR(map);
1055 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1056 err = -EPERM;
1057 goto err_put;
1058 }
1059
1060 if (ukey) {
1061 key = __bpf_copy_key(ukey, map->key_size);
1062 if (IS_ERR(key)) {
1063 err = PTR_ERR(key);
1064 goto err_put;
1065 }
1066 } else {
1067 key = NULL;
1068 }
1069
1070 err = -ENOMEM;
1071 next_key = kmalloc(map->key_size, GFP_USER);
1072 if (!next_key)
1073 goto free_key;
1074
1075 if (bpf_map_is_dev_bound(map)) {
1076 err = bpf_map_offload_get_next_key(map, key, next_key);
1077 goto out;
1078 }
1079
1080 rcu_read_lock();
1081 err = map->ops->map_get_next_key(map, key, next_key);
1082 rcu_read_unlock();
1083 out:
1084 if (err)
1085 goto free_next_key;
1086
1087 err = -EFAULT;
1088 if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1089 goto free_next_key;
1090
1091 err = 0;
1092
1093 free_next_key:
1094 kfree(next_key);
1095 free_key:
1096 kfree(key);
1097 err_put:
1098 fdput(f);
1099 return err;
1100 }
1101
1102 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1103
map_lookup_and_delete_elem(union bpf_attr * attr)1104 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1105 {
1106 void __user *ukey = u64_to_user_ptr(attr->key);
1107 void __user *uvalue = u64_to_user_ptr(attr->value);
1108 int ufd = attr->map_fd;
1109 struct bpf_map *map;
1110 void *key, *value;
1111 u32 value_size;
1112 struct fd f;
1113 int err;
1114
1115 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1116 return -EINVAL;
1117
1118 f = fdget(ufd);
1119 map = __bpf_map_get(f);
1120 if (IS_ERR(map))
1121 return PTR_ERR(map);
1122 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1123 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1124 err = -EPERM;
1125 goto err_put;
1126 }
1127
1128 key = __bpf_copy_key(ukey, map->key_size);
1129 if (IS_ERR(key)) {
1130 err = PTR_ERR(key);
1131 goto err_put;
1132 }
1133
1134 value_size = map->value_size;
1135
1136 err = -ENOMEM;
1137 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1138 if (!value)
1139 goto free_key;
1140
1141 if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1142 map->map_type == BPF_MAP_TYPE_STACK) {
1143 err = map->ops->map_pop_elem(map, value);
1144 } else {
1145 err = -ENOTSUPP;
1146 }
1147
1148 if (err)
1149 goto free_value;
1150
1151 if (copy_to_user(uvalue, value, value_size) != 0) {
1152 err = -EFAULT;
1153 goto free_value;
1154 }
1155
1156 err = 0;
1157
1158 free_value:
1159 kfree(value);
1160 free_key:
1161 kfree(key);
1162 err_put:
1163 fdput(f);
1164 return err;
1165 }
1166
1167 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1168
map_freeze(const union bpf_attr * attr)1169 static int map_freeze(const union bpf_attr *attr)
1170 {
1171 int err = 0, ufd = attr->map_fd;
1172 struct bpf_map *map;
1173 struct fd f;
1174
1175 if (CHECK_ATTR(BPF_MAP_FREEZE))
1176 return -EINVAL;
1177
1178 f = fdget(ufd);
1179 map = __bpf_map_get(f);
1180 if (IS_ERR(map))
1181 return PTR_ERR(map);
1182 if (READ_ONCE(map->frozen)) {
1183 err = -EBUSY;
1184 goto err_put;
1185 }
1186 if (!capable(CAP_SYS_ADMIN)) {
1187 err = -EPERM;
1188 goto err_put;
1189 }
1190
1191 WRITE_ONCE(map->frozen, true);
1192 err_put:
1193 fdput(f);
1194 return err;
1195 }
1196
1197 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1198 #define BPF_PROG_TYPE(_id, _name) \
1199 [_id] = & _name ## _prog_ops,
1200 #define BPF_MAP_TYPE(_id, _ops)
1201 #include <linux/bpf_types.h>
1202 #undef BPF_PROG_TYPE
1203 #undef BPF_MAP_TYPE
1204 };
1205
find_prog_type(enum bpf_prog_type type,struct bpf_prog * prog)1206 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1207 {
1208 const struct bpf_prog_ops *ops;
1209
1210 if (type >= ARRAY_SIZE(bpf_prog_types))
1211 return -EINVAL;
1212 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1213 ops = bpf_prog_types[type];
1214 if (!ops)
1215 return -EINVAL;
1216
1217 if (!bpf_prog_is_dev_bound(prog->aux))
1218 prog->aux->ops = ops;
1219 else
1220 prog->aux->ops = &bpf_offload_prog_ops;
1221 prog->type = type;
1222 return 0;
1223 }
1224
1225 /* drop refcnt on maps used by eBPF program and free auxilary data */
free_used_maps(struct bpf_prog_aux * aux)1226 static void free_used_maps(struct bpf_prog_aux *aux)
1227 {
1228 enum bpf_cgroup_storage_type stype;
1229 int i;
1230
1231 for_each_cgroup_storage_type(stype) {
1232 if (!aux->cgroup_storage[stype])
1233 continue;
1234 bpf_cgroup_storage_release(aux->prog,
1235 aux->cgroup_storage[stype]);
1236 }
1237
1238 for (i = 0; i < aux->used_map_cnt; i++)
1239 bpf_map_put(aux->used_maps[i]);
1240
1241 kfree(aux->used_maps);
1242 }
1243
__bpf_prog_charge(struct user_struct * user,u32 pages)1244 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1245 {
1246 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1247 unsigned long user_bufs;
1248
1249 if (user) {
1250 user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1251 if (user_bufs > memlock_limit) {
1252 atomic_long_sub(pages, &user->locked_vm);
1253 return -EPERM;
1254 }
1255 }
1256
1257 return 0;
1258 }
1259
__bpf_prog_uncharge(struct user_struct * user,u32 pages)1260 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1261 {
1262 if (user)
1263 atomic_long_sub(pages, &user->locked_vm);
1264 }
1265
bpf_prog_charge_memlock(struct bpf_prog * prog)1266 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1267 {
1268 struct user_struct *user = get_current_user();
1269 int ret;
1270
1271 ret = __bpf_prog_charge(user, prog->pages);
1272 if (ret) {
1273 free_uid(user);
1274 return ret;
1275 }
1276
1277 prog->aux->user = user;
1278 return 0;
1279 }
1280
bpf_prog_uncharge_memlock(struct bpf_prog * prog)1281 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1282 {
1283 struct user_struct *user = prog->aux->user;
1284
1285 __bpf_prog_uncharge(user, prog->pages);
1286 free_uid(user);
1287 }
1288
bpf_prog_alloc_id(struct bpf_prog * prog)1289 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1290 {
1291 int id;
1292
1293 idr_preload(GFP_KERNEL);
1294 spin_lock_bh(&prog_idr_lock);
1295 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1296 if (id > 0)
1297 prog->aux->id = id;
1298 spin_unlock_bh(&prog_idr_lock);
1299 idr_preload_end();
1300
1301 /* id is in [1, INT_MAX) */
1302 if (WARN_ON_ONCE(!id))
1303 return -ENOSPC;
1304
1305 return id > 0 ? 0 : id;
1306 }
1307
bpf_prog_free_id(struct bpf_prog * prog,bool do_idr_lock)1308 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1309 {
1310 /* cBPF to eBPF migrations are currently not in the idr store.
1311 * Offloaded programs are removed from the store when their device
1312 * disappears - even if someone grabs an fd to them they are unusable,
1313 * simply waiting for refcnt to drop to be freed.
1314 */
1315 if (!prog->aux->id)
1316 return;
1317
1318 if (do_idr_lock)
1319 spin_lock_bh(&prog_idr_lock);
1320 else
1321 __acquire(&prog_idr_lock);
1322
1323 idr_remove(&prog_idr, prog->aux->id);
1324 prog->aux->id = 0;
1325
1326 if (do_idr_lock)
1327 spin_unlock_bh(&prog_idr_lock);
1328 else
1329 __release(&prog_idr_lock);
1330 }
1331
__bpf_prog_put_rcu(struct rcu_head * rcu)1332 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1333 {
1334 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1335
1336 kvfree(aux->func_info);
1337 free_used_maps(aux);
1338 bpf_prog_uncharge_memlock(aux->prog);
1339 security_bpf_prog_free(aux);
1340 bpf_prog_free(aux->prog);
1341 }
1342
__bpf_prog_put_noref(struct bpf_prog * prog,bool deferred)1343 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1344 {
1345 bpf_prog_kallsyms_del_all(prog);
1346 btf_put(prog->aux->btf);
1347 bpf_prog_free_linfo(prog);
1348
1349 if (deferred)
1350 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1351 else
1352 __bpf_prog_put_rcu(&prog->aux->rcu);
1353 }
1354
__bpf_prog_put(struct bpf_prog * prog,bool do_idr_lock)1355 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1356 {
1357 if (atomic_dec_and_test(&prog->aux->refcnt)) {
1358 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1359 /* bpf_prog_free_id() must be called first */
1360 bpf_prog_free_id(prog, do_idr_lock);
1361 __bpf_prog_put_noref(prog, true);
1362 }
1363 }
1364
bpf_prog_put(struct bpf_prog * prog)1365 void bpf_prog_put(struct bpf_prog *prog)
1366 {
1367 __bpf_prog_put(prog, true);
1368 }
1369 EXPORT_SYMBOL_GPL(bpf_prog_put);
1370
bpf_prog_release(struct inode * inode,struct file * filp)1371 static int bpf_prog_release(struct inode *inode, struct file *filp)
1372 {
1373 struct bpf_prog *prog = filp->private_data;
1374
1375 bpf_prog_put(prog);
1376 return 0;
1377 }
1378
bpf_prog_get_stats(const struct bpf_prog * prog,struct bpf_prog_stats * stats)1379 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1380 struct bpf_prog_stats *stats)
1381 {
1382 u64 nsecs = 0, cnt = 0;
1383 int cpu;
1384
1385 for_each_possible_cpu(cpu) {
1386 const struct bpf_prog_stats *st;
1387 unsigned int start;
1388 u64 tnsecs, tcnt;
1389
1390 st = per_cpu_ptr(prog->aux->stats, cpu);
1391 do {
1392 start = u64_stats_fetch_begin_irq(&st->syncp);
1393 tnsecs = st->nsecs;
1394 tcnt = st->cnt;
1395 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1396 nsecs += tnsecs;
1397 cnt += tcnt;
1398 }
1399 stats->nsecs = nsecs;
1400 stats->cnt = cnt;
1401 }
1402
1403 #ifdef CONFIG_PROC_FS
bpf_prog_show_fdinfo(struct seq_file * m,struct file * filp)1404 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1405 {
1406 const struct bpf_prog *prog = filp->private_data;
1407 char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1408 struct bpf_prog_stats stats;
1409
1410 bpf_prog_get_stats(prog, &stats);
1411 bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1412 seq_printf(m,
1413 "prog_type:\t%u\n"
1414 "prog_jited:\t%u\n"
1415 "prog_tag:\t%s\n"
1416 "memlock:\t%llu\n"
1417 "prog_id:\t%u\n"
1418 "run_time_ns:\t%llu\n"
1419 "run_cnt:\t%llu\n",
1420 prog->type,
1421 prog->jited,
1422 prog_tag,
1423 prog->pages * 1ULL << PAGE_SHIFT,
1424 prog->aux->id,
1425 stats.nsecs,
1426 stats.cnt);
1427 }
1428 #endif
1429
1430 const struct file_operations bpf_prog_fops = {
1431 #ifdef CONFIG_PROC_FS
1432 .show_fdinfo = bpf_prog_show_fdinfo,
1433 #endif
1434 .release = bpf_prog_release,
1435 .read = bpf_dummy_read,
1436 .write = bpf_dummy_write,
1437 };
1438
bpf_prog_new_fd(struct bpf_prog * prog)1439 int bpf_prog_new_fd(struct bpf_prog *prog)
1440 {
1441 int ret;
1442
1443 ret = security_bpf_prog(prog);
1444 if (ret < 0)
1445 return ret;
1446
1447 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1448 O_RDWR | O_CLOEXEC);
1449 }
1450
____bpf_prog_get(struct fd f)1451 static struct bpf_prog *____bpf_prog_get(struct fd f)
1452 {
1453 if (!f.file)
1454 return ERR_PTR(-EBADF);
1455 if (f.file->f_op != &bpf_prog_fops) {
1456 fdput(f);
1457 return ERR_PTR(-EINVAL);
1458 }
1459
1460 return f.file->private_data;
1461 }
1462
bpf_prog_add(struct bpf_prog * prog,int i)1463 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1464 {
1465 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1466 atomic_sub(i, &prog->aux->refcnt);
1467 return ERR_PTR(-EBUSY);
1468 }
1469 return prog;
1470 }
1471 EXPORT_SYMBOL_GPL(bpf_prog_add);
1472
bpf_prog_sub(struct bpf_prog * prog,int i)1473 void bpf_prog_sub(struct bpf_prog *prog, int i)
1474 {
1475 /* Only to be used for undoing previous bpf_prog_add() in some
1476 * error path. We still know that another entity in our call
1477 * path holds a reference to the program, thus atomic_sub() can
1478 * be safely used in such cases!
1479 */
1480 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1481 }
1482 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1483
bpf_prog_inc(struct bpf_prog * prog)1484 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1485 {
1486 return bpf_prog_add(prog, 1);
1487 }
1488 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1489
1490 /* prog_idr_lock should have been held */
bpf_prog_inc_not_zero(struct bpf_prog * prog)1491 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1492 {
1493 int refold;
1494
1495 refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1496
1497 if (refold >= BPF_MAX_REFCNT) {
1498 __bpf_prog_put(prog, false);
1499 return ERR_PTR(-EBUSY);
1500 }
1501
1502 if (!refold)
1503 return ERR_PTR(-ENOENT);
1504
1505 return prog;
1506 }
1507 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1508
bpf_prog_get_ok(struct bpf_prog * prog,enum bpf_prog_type * attach_type,bool attach_drv)1509 bool bpf_prog_get_ok(struct bpf_prog *prog,
1510 enum bpf_prog_type *attach_type, bool attach_drv)
1511 {
1512 /* not an attachment, just a refcount inc, always allow */
1513 if (!attach_type)
1514 return true;
1515
1516 if (prog->type != *attach_type)
1517 return false;
1518 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1519 return false;
1520
1521 return true;
1522 }
1523
__bpf_prog_get(u32 ufd,enum bpf_prog_type * attach_type,bool attach_drv)1524 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1525 bool attach_drv)
1526 {
1527 struct fd f = fdget(ufd);
1528 struct bpf_prog *prog;
1529
1530 prog = ____bpf_prog_get(f);
1531 if (IS_ERR(prog))
1532 return prog;
1533 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1534 prog = ERR_PTR(-EINVAL);
1535 goto out;
1536 }
1537
1538 prog = bpf_prog_inc(prog);
1539 out:
1540 fdput(f);
1541 return prog;
1542 }
1543
bpf_prog_get(u32 ufd)1544 struct bpf_prog *bpf_prog_get(u32 ufd)
1545 {
1546 return __bpf_prog_get(ufd, NULL, false);
1547 }
1548
bpf_prog_get_type_dev(u32 ufd,enum bpf_prog_type type,bool attach_drv)1549 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1550 bool attach_drv)
1551 {
1552 return __bpf_prog_get(ufd, &type, attach_drv);
1553 }
1554 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1555
1556 /* Initially all BPF programs could be loaded w/o specifying
1557 * expected_attach_type. Later for some of them specifying expected_attach_type
1558 * at load time became required so that program could be validated properly.
1559 * Programs of types that are allowed to be loaded both w/ and w/o (for
1560 * backward compatibility) expected_attach_type, should have the default attach
1561 * type assigned to expected_attach_type for the latter case, so that it can be
1562 * validated later at attach time.
1563 *
1564 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1565 * prog type requires it but has some attach types that have to be backward
1566 * compatible.
1567 */
bpf_prog_load_fixup_attach_type(union bpf_attr * attr)1568 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1569 {
1570 switch (attr->prog_type) {
1571 case BPF_PROG_TYPE_CGROUP_SOCK:
1572 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1573 * exist so checking for non-zero is the way to go here.
1574 */
1575 if (!attr->expected_attach_type)
1576 attr->expected_attach_type =
1577 BPF_CGROUP_INET_SOCK_CREATE;
1578 break;
1579 }
1580 }
1581
1582 static int
bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,enum bpf_attach_type expected_attach_type)1583 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1584 enum bpf_attach_type expected_attach_type)
1585 {
1586 switch (prog_type) {
1587 case BPF_PROG_TYPE_CGROUP_SOCK:
1588 switch (expected_attach_type) {
1589 case BPF_CGROUP_INET_SOCK_CREATE:
1590 case BPF_CGROUP_INET4_POST_BIND:
1591 case BPF_CGROUP_INET6_POST_BIND:
1592 return 0;
1593 default:
1594 return -EINVAL;
1595 }
1596 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1597 switch (expected_attach_type) {
1598 case BPF_CGROUP_INET4_BIND:
1599 case BPF_CGROUP_INET6_BIND:
1600 case BPF_CGROUP_INET4_CONNECT:
1601 case BPF_CGROUP_INET6_CONNECT:
1602 case BPF_CGROUP_UDP4_SENDMSG:
1603 case BPF_CGROUP_UDP6_SENDMSG:
1604 case BPF_CGROUP_UDP4_RECVMSG:
1605 case BPF_CGROUP_UDP6_RECVMSG:
1606 return 0;
1607 default:
1608 return -EINVAL;
1609 }
1610 case BPF_PROG_TYPE_CGROUP_SKB:
1611 switch (expected_attach_type) {
1612 case BPF_CGROUP_INET_INGRESS:
1613 case BPF_CGROUP_INET_EGRESS:
1614 return 0;
1615 default:
1616 return -EINVAL;
1617 }
1618 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1619 switch (expected_attach_type) {
1620 case BPF_CGROUP_SETSOCKOPT:
1621 case BPF_CGROUP_GETSOCKOPT:
1622 return 0;
1623 default:
1624 return -EINVAL;
1625 }
1626 default:
1627 return 0;
1628 }
1629 }
1630
1631 /* last field in 'union bpf_attr' used by this command */
1632 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt
1633
bpf_prog_load(union bpf_attr * attr,union bpf_attr __user * uattr)1634 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
1635 {
1636 enum bpf_prog_type type = attr->prog_type;
1637 struct bpf_prog *prog;
1638 int err;
1639 char license[128];
1640 bool is_gpl;
1641
1642 if (CHECK_ATTR(BPF_PROG_LOAD))
1643 return -EINVAL;
1644
1645 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
1646 BPF_F_ANY_ALIGNMENT |
1647 BPF_F_TEST_STATE_FREQ |
1648 BPF_F_TEST_RND_HI32))
1649 return -EINVAL;
1650
1651 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
1652 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
1653 !capable(CAP_SYS_ADMIN))
1654 return -EPERM;
1655
1656 /* copy eBPF program license from user space */
1657 if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1658 sizeof(license) - 1) < 0)
1659 return -EFAULT;
1660 license[sizeof(license) - 1] = 0;
1661
1662 /* eBPF programs must be GPL compatible to use GPL-ed functions */
1663 is_gpl = license_is_gpl_compatible(license);
1664
1665 if (attr->insn_cnt == 0 ||
1666 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
1667 return -E2BIG;
1668 if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1669 type != BPF_PROG_TYPE_CGROUP_SKB &&
1670 !capable(CAP_SYS_ADMIN))
1671 return -EPERM;
1672
1673 bpf_prog_load_fixup_attach_type(attr);
1674 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1675 return -EINVAL;
1676
1677 /* plain bpf_prog allocation */
1678 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1679 if (!prog)
1680 return -ENOMEM;
1681
1682 prog->expected_attach_type = attr->expected_attach_type;
1683
1684 prog->aux->offload_requested = !!attr->prog_ifindex;
1685
1686 err = security_bpf_prog_alloc(prog->aux);
1687 if (err)
1688 goto free_prog_nouncharge;
1689
1690 err = bpf_prog_charge_memlock(prog);
1691 if (err)
1692 goto free_prog_sec;
1693
1694 prog->len = attr->insn_cnt;
1695
1696 err = -EFAULT;
1697 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1698 bpf_prog_insn_size(prog)) != 0)
1699 goto free_prog;
1700
1701 prog->orig_prog = NULL;
1702 prog->jited = 0;
1703
1704 atomic_set(&prog->aux->refcnt, 1);
1705 prog->gpl_compatible = is_gpl ? 1 : 0;
1706
1707 if (bpf_prog_is_dev_bound(prog->aux)) {
1708 err = bpf_prog_offload_init(prog, attr);
1709 if (err)
1710 goto free_prog;
1711 }
1712
1713 /* find program type: socket_filter vs tracing_filter */
1714 err = find_prog_type(type, prog);
1715 if (err < 0)
1716 goto free_prog;
1717
1718 prog->aux->load_time = ktime_get_boottime_ns();
1719 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1720 if (err)
1721 goto free_prog;
1722
1723 /* run eBPF verifier */
1724 err = bpf_check(&prog, attr, uattr);
1725 if (err < 0)
1726 goto free_used_maps;
1727
1728 prog = bpf_prog_select_runtime(prog, &err);
1729 if (err < 0)
1730 goto free_used_maps;
1731
1732 err = bpf_prog_alloc_id(prog);
1733 if (err)
1734 goto free_used_maps;
1735
1736 /* Upon success of bpf_prog_alloc_id(), the BPF prog is
1737 * effectively publicly exposed. However, retrieving via
1738 * bpf_prog_get_fd_by_id() will take another reference,
1739 * therefore it cannot be gone underneath us.
1740 *
1741 * Only for the time /after/ successful bpf_prog_new_fd()
1742 * and before returning to userspace, we might just hold
1743 * one reference and any parallel close on that fd could
1744 * rip everything out. Hence, below notifications must
1745 * happen before bpf_prog_new_fd().
1746 *
1747 * Also, any failure handling from this point onwards must
1748 * be using bpf_prog_put() given the program is exposed.
1749 */
1750 bpf_prog_kallsyms_add(prog);
1751 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
1752
1753 err = bpf_prog_new_fd(prog);
1754 if (err < 0)
1755 bpf_prog_put(prog);
1756 return err;
1757
1758 free_used_maps:
1759 /* In case we have subprogs, we need to wait for a grace
1760 * period before we can tear down JIT memory since symbols
1761 * are already exposed under kallsyms.
1762 */
1763 __bpf_prog_put_noref(prog, prog->aux->func_cnt);
1764 return err;
1765 free_prog:
1766 bpf_prog_uncharge_memlock(prog);
1767 free_prog_sec:
1768 security_bpf_prog_free(prog->aux);
1769 free_prog_nouncharge:
1770 bpf_prog_free(prog);
1771 return err;
1772 }
1773
1774 #define BPF_OBJ_LAST_FIELD file_flags
1775
bpf_obj_pin(const union bpf_attr * attr)1776 static int bpf_obj_pin(const union bpf_attr *attr)
1777 {
1778 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1779 return -EINVAL;
1780
1781 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1782 }
1783
bpf_obj_get(const union bpf_attr * attr)1784 static int bpf_obj_get(const union bpf_attr *attr)
1785 {
1786 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1787 attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1788 return -EINVAL;
1789
1790 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1791 attr->file_flags);
1792 }
1793
1794 struct bpf_raw_tracepoint {
1795 struct bpf_raw_event_map *btp;
1796 struct bpf_prog *prog;
1797 };
1798
bpf_raw_tracepoint_release(struct inode * inode,struct file * filp)1799 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1800 {
1801 struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1802
1803 if (raw_tp->prog) {
1804 bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1805 bpf_prog_put(raw_tp->prog);
1806 }
1807 bpf_put_raw_tracepoint(raw_tp->btp);
1808 kfree(raw_tp);
1809 return 0;
1810 }
1811
1812 static const struct file_operations bpf_raw_tp_fops = {
1813 .release = bpf_raw_tracepoint_release,
1814 .read = bpf_dummy_read,
1815 .write = bpf_dummy_write,
1816 };
1817
1818 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1819
bpf_raw_tracepoint_open(const union bpf_attr * attr)1820 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1821 {
1822 struct bpf_raw_tracepoint *raw_tp;
1823 struct bpf_raw_event_map *btp;
1824 struct bpf_prog *prog;
1825 char tp_name[128];
1826 int tp_fd, err;
1827
1828 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1829 sizeof(tp_name) - 1) < 0)
1830 return -EFAULT;
1831 tp_name[sizeof(tp_name) - 1] = 0;
1832
1833 btp = bpf_get_raw_tracepoint(tp_name);
1834 if (!btp)
1835 return -ENOENT;
1836
1837 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1838 if (!raw_tp) {
1839 err = -ENOMEM;
1840 goto out_put_btp;
1841 }
1842 raw_tp->btp = btp;
1843
1844 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
1845 if (IS_ERR(prog)) {
1846 err = PTR_ERR(prog);
1847 goto out_free_tp;
1848 }
1849 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
1850 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
1851 err = -EINVAL;
1852 goto out_put_prog;
1853 }
1854
1855 err = bpf_probe_register(raw_tp->btp, prog);
1856 if (err)
1857 goto out_put_prog;
1858
1859 raw_tp->prog = prog;
1860 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1861 O_CLOEXEC);
1862 if (tp_fd < 0) {
1863 bpf_probe_unregister(raw_tp->btp, prog);
1864 err = tp_fd;
1865 goto out_put_prog;
1866 }
1867 return tp_fd;
1868
1869 out_put_prog:
1870 bpf_prog_put(prog);
1871 out_free_tp:
1872 kfree(raw_tp);
1873 out_put_btp:
1874 bpf_put_raw_tracepoint(btp);
1875 return err;
1876 }
1877
bpf_prog_attach_check_attach_type(const struct bpf_prog * prog,enum bpf_attach_type attach_type)1878 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1879 enum bpf_attach_type attach_type)
1880 {
1881 switch (prog->type) {
1882 case BPF_PROG_TYPE_CGROUP_SOCK:
1883 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1884 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1885 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1886 case BPF_PROG_TYPE_CGROUP_SKB:
1887 return prog->enforce_expected_attach_type &&
1888 prog->expected_attach_type != attach_type ?
1889 -EINVAL : 0;
1890 default:
1891 return 0;
1892 }
1893 }
1894
1895 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1896
1897 #define BPF_F_ATTACH_MASK \
1898 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1899
bpf_prog_attach(const union bpf_attr * attr)1900 static int bpf_prog_attach(const union bpf_attr *attr)
1901 {
1902 enum bpf_prog_type ptype;
1903 struct bpf_prog *prog;
1904 int ret;
1905
1906 if (!capable(CAP_NET_ADMIN))
1907 return -EPERM;
1908
1909 if (CHECK_ATTR(BPF_PROG_ATTACH))
1910 return -EINVAL;
1911
1912 if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1913 return -EINVAL;
1914
1915 switch (attr->attach_type) {
1916 case BPF_CGROUP_INET_INGRESS:
1917 case BPF_CGROUP_INET_EGRESS:
1918 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1919 break;
1920 case BPF_CGROUP_INET_SOCK_CREATE:
1921 case BPF_CGROUP_INET4_POST_BIND:
1922 case BPF_CGROUP_INET6_POST_BIND:
1923 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1924 break;
1925 case BPF_CGROUP_INET4_BIND:
1926 case BPF_CGROUP_INET6_BIND:
1927 case BPF_CGROUP_INET4_CONNECT:
1928 case BPF_CGROUP_INET6_CONNECT:
1929 case BPF_CGROUP_UDP4_SENDMSG:
1930 case BPF_CGROUP_UDP6_SENDMSG:
1931 case BPF_CGROUP_UDP4_RECVMSG:
1932 case BPF_CGROUP_UDP6_RECVMSG:
1933 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1934 break;
1935 case BPF_CGROUP_SOCK_OPS:
1936 ptype = BPF_PROG_TYPE_SOCK_OPS;
1937 break;
1938 case BPF_CGROUP_DEVICE:
1939 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1940 break;
1941 case BPF_SK_MSG_VERDICT:
1942 ptype = BPF_PROG_TYPE_SK_MSG;
1943 break;
1944 case BPF_SK_SKB_STREAM_PARSER:
1945 case BPF_SK_SKB_STREAM_VERDICT:
1946 ptype = BPF_PROG_TYPE_SK_SKB;
1947 break;
1948 case BPF_LIRC_MODE2:
1949 ptype = BPF_PROG_TYPE_LIRC_MODE2;
1950 break;
1951 case BPF_FLOW_DISSECTOR:
1952 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1953 break;
1954 case BPF_CGROUP_SYSCTL:
1955 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
1956 break;
1957 case BPF_CGROUP_GETSOCKOPT:
1958 case BPF_CGROUP_SETSOCKOPT:
1959 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
1960 break;
1961 default:
1962 return -EINVAL;
1963 }
1964
1965 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1966 if (IS_ERR(prog))
1967 return PTR_ERR(prog);
1968
1969 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1970 bpf_prog_put(prog);
1971 return -EINVAL;
1972 }
1973
1974 switch (ptype) {
1975 case BPF_PROG_TYPE_SK_SKB:
1976 case BPF_PROG_TYPE_SK_MSG:
1977 ret = sock_map_get_from_fd(attr, prog);
1978 break;
1979 case BPF_PROG_TYPE_LIRC_MODE2:
1980 ret = lirc_prog_attach(attr, prog);
1981 break;
1982 case BPF_PROG_TYPE_FLOW_DISSECTOR:
1983 ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1984 break;
1985 default:
1986 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1987 }
1988
1989 if (ret)
1990 bpf_prog_put(prog);
1991 return ret;
1992 }
1993
1994 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1995
bpf_prog_detach(const union bpf_attr * attr)1996 static int bpf_prog_detach(const union bpf_attr *attr)
1997 {
1998 enum bpf_prog_type ptype;
1999
2000 if (!capable(CAP_NET_ADMIN))
2001 return -EPERM;
2002
2003 if (CHECK_ATTR(BPF_PROG_DETACH))
2004 return -EINVAL;
2005
2006 switch (attr->attach_type) {
2007 case BPF_CGROUP_INET_INGRESS:
2008 case BPF_CGROUP_INET_EGRESS:
2009 ptype = BPF_PROG_TYPE_CGROUP_SKB;
2010 break;
2011 case BPF_CGROUP_INET_SOCK_CREATE:
2012 case BPF_CGROUP_INET4_POST_BIND:
2013 case BPF_CGROUP_INET6_POST_BIND:
2014 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
2015 break;
2016 case BPF_CGROUP_INET4_BIND:
2017 case BPF_CGROUP_INET6_BIND:
2018 case BPF_CGROUP_INET4_CONNECT:
2019 case BPF_CGROUP_INET6_CONNECT:
2020 case BPF_CGROUP_UDP4_SENDMSG:
2021 case BPF_CGROUP_UDP6_SENDMSG:
2022 case BPF_CGROUP_UDP4_RECVMSG:
2023 case BPF_CGROUP_UDP6_RECVMSG:
2024 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
2025 break;
2026 case BPF_CGROUP_SOCK_OPS:
2027 ptype = BPF_PROG_TYPE_SOCK_OPS;
2028 break;
2029 case BPF_CGROUP_DEVICE:
2030 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
2031 break;
2032 case BPF_SK_MSG_VERDICT:
2033 return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_MSG);
2034 case BPF_SK_SKB_STREAM_PARSER:
2035 case BPF_SK_SKB_STREAM_VERDICT:
2036 return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_SKB);
2037 case BPF_LIRC_MODE2:
2038 return lirc_prog_detach(attr);
2039 case BPF_FLOW_DISSECTOR:
2040 return skb_flow_dissector_bpf_prog_detach(attr);
2041 case BPF_CGROUP_SYSCTL:
2042 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
2043 break;
2044 case BPF_CGROUP_GETSOCKOPT:
2045 case BPF_CGROUP_SETSOCKOPT:
2046 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
2047 break;
2048 default:
2049 return -EINVAL;
2050 }
2051
2052 return cgroup_bpf_prog_detach(attr, ptype);
2053 }
2054
2055 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
2056
bpf_prog_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2057 static int bpf_prog_query(const union bpf_attr *attr,
2058 union bpf_attr __user *uattr)
2059 {
2060 if (!capable(CAP_NET_ADMIN))
2061 return -EPERM;
2062 if (CHECK_ATTR(BPF_PROG_QUERY))
2063 return -EINVAL;
2064 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
2065 return -EINVAL;
2066
2067 switch (attr->query.attach_type) {
2068 case BPF_CGROUP_INET_INGRESS:
2069 case BPF_CGROUP_INET_EGRESS:
2070 case BPF_CGROUP_INET_SOCK_CREATE:
2071 case BPF_CGROUP_INET4_BIND:
2072 case BPF_CGROUP_INET6_BIND:
2073 case BPF_CGROUP_INET4_POST_BIND:
2074 case BPF_CGROUP_INET6_POST_BIND:
2075 case BPF_CGROUP_INET4_CONNECT:
2076 case BPF_CGROUP_INET6_CONNECT:
2077 case BPF_CGROUP_UDP4_SENDMSG:
2078 case BPF_CGROUP_UDP6_SENDMSG:
2079 case BPF_CGROUP_UDP4_RECVMSG:
2080 case BPF_CGROUP_UDP6_RECVMSG:
2081 case BPF_CGROUP_SOCK_OPS:
2082 case BPF_CGROUP_DEVICE:
2083 case BPF_CGROUP_SYSCTL:
2084 case BPF_CGROUP_GETSOCKOPT:
2085 case BPF_CGROUP_SETSOCKOPT:
2086 break;
2087 case BPF_LIRC_MODE2:
2088 return lirc_prog_query(attr, uattr);
2089 case BPF_FLOW_DISSECTOR:
2090 return skb_flow_dissector_prog_query(attr, uattr);
2091 default:
2092 return -EINVAL;
2093 }
2094
2095 return cgroup_bpf_prog_query(attr, uattr);
2096 }
2097
2098 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
2099
bpf_prog_test_run(const union bpf_attr * attr,union bpf_attr __user * uattr)2100 static int bpf_prog_test_run(const union bpf_attr *attr,
2101 union bpf_attr __user *uattr)
2102 {
2103 struct bpf_prog *prog;
2104 int ret = -ENOTSUPP;
2105
2106 if (!capable(CAP_SYS_ADMIN))
2107 return -EPERM;
2108 if (CHECK_ATTR(BPF_PROG_TEST_RUN))
2109 return -EINVAL;
2110
2111 if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
2112 (!attr->test.ctx_size_in && attr->test.ctx_in))
2113 return -EINVAL;
2114
2115 if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
2116 (!attr->test.ctx_size_out && attr->test.ctx_out))
2117 return -EINVAL;
2118
2119 prog = bpf_prog_get(attr->test.prog_fd);
2120 if (IS_ERR(prog))
2121 return PTR_ERR(prog);
2122
2123 if (prog->aux->ops->test_run)
2124 ret = prog->aux->ops->test_run(prog, attr, uattr);
2125
2126 bpf_prog_put(prog);
2127 return ret;
2128 }
2129
2130 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
2131
bpf_obj_get_next_id(const union bpf_attr * attr,union bpf_attr __user * uattr,struct idr * idr,spinlock_t * lock)2132 static int bpf_obj_get_next_id(const union bpf_attr *attr,
2133 union bpf_attr __user *uattr,
2134 struct idr *idr,
2135 spinlock_t *lock)
2136 {
2137 u32 next_id = attr->start_id;
2138 int err = 0;
2139
2140 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
2141 return -EINVAL;
2142
2143 if (!capable(CAP_SYS_ADMIN))
2144 return -EPERM;
2145
2146 next_id++;
2147 spin_lock_bh(lock);
2148 if (!idr_get_next(idr, &next_id))
2149 err = -ENOENT;
2150 spin_unlock_bh(lock);
2151
2152 if (!err)
2153 err = put_user(next_id, &uattr->next_id);
2154
2155 return err;
2156 }
2157
2158 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
2159
bpf_prog_get_fd_by_id(const union bpf_attr * attr)2160 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
2161 {
2162 struct bpf_prog *prog;
2163 u32 id = attr->prog_id;
2164 int fd;
2165
2166 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
2167 return -EINVAL;
2168
2169 if (!capable(CAP_SYS_ADMIN))
2170 return -EPERM;
2171
2172 spin_lock_bh(&prog_idr_lock);
2173 prog = idr_find(&prog_idr, id);
2174 if (prog)
2175 prog = bpf_prog_inc_not_zero(prog);
2176 else
2177 prog = ERR_PTR(-ENOENT);
2178 spin_unlock_bh(&prog_idr_lock);
2179
2180 if (IS_ERR(prog))
2181 return PTR_ERR(prog);
2182
2183 fd = bpf_prog_new_fd(prog);
2184 if (fd < 0)
2185 bpf_prog_put(prog);
2186
2187 return fd;
2188 }
2189
2190 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
2191
bpf_map_get_fd_by_id(const union bpf_attr * attr)2192 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
2193 {
2194 struct bpf_map *map;
2195 u32 id = attr->map_id;
2196 int f_flags;
2197 int fd;
2198
2199 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
2200 attr->open_flags & ~BPF_OBJ_FLAG_MASK)
2201 return -EINVAL;
2202
2203 if (!capable(CAP_SYS_ADMIN))
2204 return -EPERM;
2205
2206 f_flags = bpf_get_file_flag(attr->open_flags);
2207 if (f_flags < 0)
2208 return f_flags;
2209
2210 spin_lock_bh(&map_idr_lock);
2211 map = idr_find(&map_idr, id);
2212 if (map)
2213 map = __bpf_map_inc_not_zero(map, true);
2214 else
2215 map = ERR_PTR(-ENOENT);
2216 spin_unlock_bh(&map_idr_lock);
2217
2218 if (IS_ERR(map))
2219 return PTR_ERR(map);
2220
2221 fd = bpf_map_new_fd(map, f_flags);
2222 if (fd < 0)
2223 bpf_map_put_with_uref(map);
2224
2225 return fd;
2226 }
2227
bpf_map_from_imm(const struct bpf_prog * prog,unsigned long addr,u32 * off,u32 * type)2228 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
2229 unsigned long addr, u32 *off,
2230 u32 *type)
2231 {
2232 const struct bpf_map *map;
2233 int i;
2234
2235 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
2236 map = prog->aux->used_maps[i];
2237 if (map == (void *)addr) {
2238 *type = BPF_PSEUDO_MAP_FD;
2239 return map;
2240 }
2241 if (!map->ops->map_direct_value_meta)
2242 continue;
2243 if (!map->ops->map_direct_value_meta(map, addr, off)) {
2244 *type = BPF_PSEUDO_MAP_VALUE;
2245 return map;
2246 }
2247 }
2248
2249 return NULL;
2250 }
2251
bpf_insn_prepare_dump(const struct bpf_prog * prog,const struct cred * f_cred)2252 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
2253 const struct cred *f_cred)
2254 {
2255 const struct bpf_map *map;
2256 struct bpf_insn *insns;
2257 u32 off, type;
2258 u64 imm;
2259 int i;
2260
2261 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
2262 GFP_USER);
2263 if (!insns)
2264 return insns;
2265
2266 for (i = 0; i < prog->len; i++) {
2267 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
2268 insns[i].code = BPF_JMP | BPF_CALL;
2269 insns[i].imm = BPF_FUNC_tail_call;
2270 /* fall-through */
2271 }
2272 if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2273 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2274 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2275 insns[i].code = BPF_JMP | BPF_CALL;
2276 if (!bpf_dump_raw_ok(f_cred))
2277 insns[i].imm = 0;
2278 continue;
2279 }
2280
2281 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2282 continue;
2283
2284 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2285 map = bpf_map_from_imm(prog, imm, &off, &type);
2286 if (map) {
2287 insns[i].src_reg = type;
2288 insns[i].imm = map->id;
2289 insns[i + 1].imm = off;
2290 continue;
2291 }
2292 }
2293
2294 return insns;
2295 }
2296
set_info_rec_size(struct bpf_prog_info * info)2297 static int set_info_rec_size(struct bpf_prog_info *info)
2298 {
2299 /*
2300 * Ensure info.*_rec_size is the same as kernel expected size
2301 *
2302 * or
2303 *
2304 * Only allow zero *_rec_size if both _rec_size and _cnt are
2305 * zero. In this case, the kernel will set the expected
2306 * _rec_size back to the info.
2307 */
2308
2309 if ((info->nr_func_info || info->func_info_rec_size) &&
2310 info->func_info_rec_size != sizeof(struct bpf_func_info))
2311 return -EINVAL;
2312
2313 if ((info->nr_line_info || info->line_info_rec_size) &&
2314 info->line_info_rec_size != sizeof(struct bpf_line_info))
2315 return -EINVAL;
2316
2317 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
2318 info->jited_line_info_rec_size != sizeof(__u64))
2319 return -EINVAL;
2320
2321 info->func_info_rec_size = sizeof(struct bpf_func_info);
2322 info->line_info_rec_size = sizeof(struct bpf_line_info);
2323 info->jited_line_info_rec_size = sizeof(__u64);
2324
2325 return 0;
2326 }
2327
bpf_prog_get_info_by_fd(struct file * file,struct bpf_prog * prog,const union bpf_attr * attr,union bpf_attr __user * uattr)2328 static int bpf_prog_get_info_by_fd(struct file *file,
2329 struct bpf_prog *prog,
2330 const union bpf_attr *attr,
2331 union bpf_attr __user *uattr)
2332 {
2333 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2334 struct bpf_prog_info info;
2335 u32 info_len = attr->info.info_len;
2336 struct bpf_prog_stats stats;
2337 char __user *uinsns;
2338 u32 ulen;
2339 int err;
2340
2341 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2342 if (err)
2343 return err;
2344 info_len = min_t(u32, sizeof(info), info_len);
2345
2346 memset(&info, 0, sizeof(info));
2347 if (copy_from_user(&info, uinfo, info_len))
2348 return -EFAULT;
2349
2350 info.type = prog->type;
2351 info.id = prog->aux->id;
2352 info.load_time = prog->aux->load_time;
2353 info.created_by_uid = from_kuid_munged(current_user_ns(),
2354 prog->aux->user->uid);
2355 info.gpl_compatible = prog->gpl_compatible;
2356
2357 memcpy(info.tag, prog->tag, sizeof(prog->tag));
2358 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2359
2360 ulen = info.nr_map_ids;
2361 info.nr_map_ids = prog->aux->used_map_cnt;
2362 ulen = min_t(u32, info.nr_map_ids, ulen);
2363 if (ulen) {
2364 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2365 u32 i;
2366
2367 for (i = 0; i < ulen; i++)
2368 if (put_user(prog->aux->used_maps[i]->id,
2369 &user_map_ids[i]))
2370 return -EFAULT;
2371 }
2372
2373 err = set_info_rec_size(&info);
2374 if (err)
2375 return err;
2376
2377 bpf_prog_get_stats(prog, &stats);
2378 info.run_time_ns = stats.nsecs;
2379 info.run_cnt = stats.cnt;
2380
2381 if (!capable(CAP_SYS_ADMIN)) {
2382 info.jited_prog_len = 0;
2383 info.xlated_prog_len = 0;
2384 info.nr_jited_ksyms = 0;
2385 info.nr_jited_func_lens = 0;
2386 info.nr_func_info = 0;
2387 info.nr_line_info = 0;
2388 info.nr_jited_line_info = 0;
2389 goto done;
2390 }
2391
2392 ulen = info.xlated_prog_len;
2393 info.xlated_prog_len = bpf_prog_insn_size(prog);
2394 if (info.xlated_prog_len && ulen) {
2395 struct bpf_insn *insns_sanitized;
2396 bool fault;
2397
2398 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
2399 info.xlated_prog_insns = 0;
2400 goto done;
2401 }
2402 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
2403 if (!insns_sanitized)
2404 return -ENOMEM;
2405 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2406 ulen = min_t(u32, info.xlated_prog_len, ulen);
2407 fault = copy_to_user(uinsns, insns_sanitized, ulen);
2408 kfree(insns_sanitized);
2409 if (fault)
2410 return -EFAULT;
2411 }
2412
2413 if (bpf_prog_is_dev_bound(prog->aux)) {
2414 err = bpf_prog_offload_info_fill(&info, prog);
2415 if (err)
2416 return err;
2417 goto done;
2418 }
2419
2420 /* NOTE: the following code is supposed to be skipped for offload.
2421 * bpf_prog_offload_info_fill() is the place to fill similar fields
2422 * for offload.
2423 */
2424 ulen = info.jited_prog_len;
2425 if (prog->aux->func_cnt) {
2426 u32 i;
2427
2428 info.jited_prog_len = 0;
2429 for (i = 0; i < prog->aux->func_cnt; i++)
2430 info.jited_prog_len += prog->aux->func[i]->jited_len;
2431 } else {
2432 info.jited_prog_len = prog->jited_len;
2433 }
2434
2435 if (info.jited_prog_len && ulen) {
2436 if (bpf_dump_raw_ok(file->f_cred)) {
2437 uinsns = u64_to_user_ptr(info.jited_prog_insns);
2438 ulen = min_t(u32, info.jited_prog_len, ulen);
2439
2440 /* for multi-function programs, copy the JITed
2441 * instructions for all the functions
2442 */
2443 if (prog->aux->func_cnt) {
2444 u32 len, free, i;
2445 u8 *img;
2446
2447 free = ulen;
2448 for (i = 0; i < prog->aux->func_cnt; i++) {
2449 len = prog->aux->func[i]->jited_len;
2450 len = min_t(u32, len, free);
2451 img = (u8 *) prog->aux->func[i]->bpf_func;
2452 if (copy_to_user(uinsns, img, len))
2453 return -EFAULT;
2454 uinsns += len;
2455 free -= len;
2456 if (!free)
2457 break;
2458 }
2459 } else {
2460 if (copy_to_user(uinsns, prog->bpf_func, ulen))
2461 return -EFAULT;
2462 }
2463 } else {
2464 info.jited_prog_insns = 0;
2465 }
2466 }
2467
2468 ulen = info.nr_jited_ksyms;
2469 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2470 if (ulen) {
2471 if (bpf_dump_raw_ok(file->f_cred)) {
2472 unsigned long ksym_addr;
2473 u64 __user *user_ksyms;
2474 u32 i;
2475
2476 /* copy the address of the kernel symbol
2477 * corresponding to each function
2478 */
2479 ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2480 user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2481 if (prog->aux->func_cnt) {
2482 for (i = 0; i < ulen; i++) {
2483 ksym_addr = (unsigned long)
2484 prog->aux->func[i]->bpf_func;
2485 if (put_user((u64) ksym_addr,
2486 &user_ksyms[i]))
2487 return -EFAULT;
2488 }
2489 } else {
2490 ksym_addr = (unsigned long) prog->bpf_func;
2491 if (put_user((u64) ksym_addr, &user_ksyms[0]))
2492 return -EFAULT;
2493 }
2494 } else {
2495 info.jited_ksyms = 0;
2496 }
2497 }
2498
2499 ulen = info.nr_jited_func_lens;
2500 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2501 if (ulen) {
2502 if (bpf_dump_raw_ok(file->f_cred)) {
2503 u32 __user *user_lens;
2504 u32 func_len, i;
2505
2506 /* copy the JITed image lengths for each function */
2507 ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2508 user_lens = u64_to_user_ptr(info.jited_func_lens);
2509 if (prog->aux->func_cnt) {
2510 for (i = 0; i < ulen; i++) {
2511 func_len =
2512 prog->aux->func[i]->jited_len;
2513 if (put_user(func_len, &user_lens[i]))
2514 return -EFAULT;
2515 }
2516 } else {
2517 func_len = prog->jited_len;
2518 if (put_user(func_len, &user_lens[0]))
2519 return -EFAULT;
2520 }
2521 } else {
2522 info.jited_func_lens = 0;
2523 }
2524 }
2525
2526 if (prog->aux->btf)
2527 info.btf_id = btf_id(prog->aux->btf);
2528
2529 ulen = info.nr_func_info;
2530 info.nr_func_info = prog->aux->func_info_cnt;
2531 if (info.nr_func_info && ulen) {
2532 char __user *user_finfo;
2533
2534 user_finfo = u64_to_user_ptr(info.func_info);
2535 ulen = min_t(u32, info.nr_func_info, ulen);
2536 if (copy_to_user(user_finfo, prog->aux->func_info,
2537 info.func_info_rec_size * ulen))
2538 return -EFAULT;
2539 }
2540
2541 ulen = info.nr_line_info;
2542 info.nr_line_info = prog->aux->nr_linfo;
2543 if (info.nr_line_info && ulen) {
2544 __u8 __user *user_linfo;
2545
2546 user_linfo = u64_to_user_ptr(info.line_info);
2547 ulen = min_t(u32, info.nr_line_info, ulen);
2548 if (copy_to_user(user_linfo, prog->aux->linfo,
2549 info.line_info_rec_size * ulen))
2550 return -EFAULT;
2551 }
2552
2553 ulen = info.nr_jited_line_info;
2554 if (prog->aux->jited_linfo)
2555 info.nr_jited_line_info = prog->aux->nr_linfo;
2556 else
2557 info.nr_jited_line_info = 0;
2558 if (info.nr_jited_line_info && ulen) {
2559 if (bpf_dump_raw_ok(file->f_cred)) {
2560 __u64 __user *user_linfo;
2561 u32 i;
2562
2563 user_linfo = u64_to_user_ptr(info.jited_line_info);
2564 ulen = min_t(u32, info.nr_jited_line_info, ulen);
2565 for (i = 0; i < ulen; i++) {
2566 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
2567 &user_linfo[i]))
2568 return -EFAULT;
2569 }
2570 } else {
2571 info.jited_line_info = 0;
2572 }
2573 }
2574
2575 ulen = info.nr_prog_tags;
2576 info.nr_prog_tags = prog->aux->func_cnt ? : 1;
2577 if (ulen) {
2578 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
2579 u32 i;
2580
2581 user_prog_tags = u64_to_user_ptr(info.prog_tags);
2582 ulen = min_t(u32, info.nr_prog_tags, ulen);
2583 if (prog->aux->func_cnt) {
2584 for (i = 0; i < ulen; i++) {
2585 if (copy_to_user(user_prog_tags[i],
2586 prog->aux->func[i]->tag,
2587 BPF_TAG_SIZE))
2588 return -EFAULT;
2589 }
2590 } else {
2591 if (copy_to_user(user_prog_tags[0],
2592 prog->tag, BPF_TAG_SIZE))
2593 return -EFAULT;
2594 }
2595 }
2596
2597 done:
2598 if (copy_to_user(uinfo, &info, info_len) ||
2599 put_user(info_len, &uattr->info.info_len))
2600 return -EFAULT;
2601
2602 return 0;
2603 }
2604
bpf_map_get_info_by_fd(struct file * file,struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)2605 static int bpf_map_get_info_by_fd(struct file *file,
2606 struct bpf_map *map,
2607 const union bpf_attr *attr,
2608 union bpf_attr __user *uattr)
2609 {
2610 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2611 struct bpf_map_info info;
2612 u32 info_len = attr->info.info_len;
2613 int err;
2614
2615 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2616 if (err)
2617 return err;
2618 info_len = min_t(u32, sizeof(info), info_len);
2619
2620 memset(&info, 0, sizeof(info));
2621 info.type = map->map_type;
2622 info.id = map->id;
2623 info.key_size = map->key_size;
2624 info.value_size = map->value_size;
2625 info.max_entries = map->max_entries;
2626 info.map_flags = map->map_flags;
2627 memcpy(info.name, map->name, sizeof(map->name));
2628
2629 if (map->btf) {
2630 info.btf_id = btf_id(map->btf);
2631 info.btf_key_type_id = map->btf_key_type_id;
2632 info.btf_value_type_id = map->btf_value_type_id;
2633 }
2634
2635 if (bpf_map_is_dev_bound(map)) {
2636 err = bpf_map_offload_info_fill(&info, map);
2637 if (err)
2638 return err;
2639 }
2640
2641 if (copy_to_user(uinfo, &info, info_len) ||
2642 put_user(info_len, &uattr->info.info_len))
2643 return -EFAULT;
2644
2645 return 0;
2646 }
2647
bpf_btf_get_info_by_fd(struct file * file,struct btf * btf,const union bpf_attr * attr,union bpf_attr __user * uattr)2648 static int bpf_btf_get_info_by_fd(struct file *file,
2649 struct btf *btf,
2650 const union bpf_attr *attr,
2651 union bpf_attr __user *uattr)
2652 {
2653 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2654 u32 info_len = attr->info.info_len;
2655 int err;
2656
2657 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2658 if (err)
2659 return err;
2660
2661 return btf_get_info_by_fd(btf, attr, uattr);
2662 }
2663
2664 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2665
bpf_obj_get_info_by_fd(const union bpf_attr * attr,union bpf_attr __user * uattr)2666 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2667 union bpf_attr __user *uattr)
2668 {
2669 int ufd = attr->info.bpf_fd;
2670 struct fd f;
2671 int err;
2672
2673 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2674 return -EINVAL;
2675
2676 f = fdget(ufd);
2677 if (!f.file)
2678 return -EBADFD;
2679
2680 if (f.file->f_op == &bpf_prog_fops)
2681 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
2682 uattr);
2683 else if (f.file->f_op == &bpf_map_fops)
2684 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
2685 uattr);
2686 else if (f.file->f_op == &btf_fops)
2687 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
2688 else
2689 err = -EINVAL;
2690
2691 fdput(f);
2692 return err;
2693 }
2694
2695 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2696
bpf_btf_load(const union bpf_attr * attr)2697 static int bpf_btf_load(const union bpf_attr *attr)
2698 {
2699 if (CHECK_ATTR(BPF_BTF_LOAD))
2700 return -EINVAL;
2701
2702 if (!capable(CAP_SYS_ADMIN))
2703 return -EPERM;
2704
2705 return btf_new_fd(attr);
2706 }
2707
2708 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2709
bpf_btf_get_fd_by_id(const union bpf_attr * attr)2710 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2711 {
2712 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2713 return -EINVAL;
2714
2715 if (!capable(CAP_SYS_ADMIN))
2716 return -EPERM;
2717
2718 return btf_get_fd_by_id(attr->btf_id);
2719 }
2720
bpf_task_fd_query_copy(const union bpf_attr * attr,union bpf_attr __user * uattr,u32 prog_id,u32 fd_type,const char * buf,u64 probe_offset,u64 probe_addr)2721 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2722 union bpf_attr __user *uattr,
2723 u32 prog_id, u32 fd_type,
2724 const char *buf, u64 probe_offset,
2725 u64 probe_addr)
2726 {
2727 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2728 u32 len = buf ? strlen(buf) : 0, input_len;
2729 int err = 0;
2730
2731 if (put_user(len, &uattr->task_fd_query.buf_len))
2732 return -EFAULT;
2733 input_len = attr->task_fd_query.buf_len;
2734 if (input_len && ubuf) {
2735 if (!len) {
2736 /* nothing to copy, just make ubuf NULL terminated */
2737 char zero = '\0';
2738
2739 if (put_user(zero, ubuf))
2740 return -EFAULT;
2741 } else if (input_len >= len + 1) {
2742 /* ubuf can hold the string with NULL terminator */
2743 if (copy_to_user(ubuf, buf, len + 1))
2744 return -EFAULT;
2745 } else {
2746 /* ubuf cannot hold the string with NULL terminator,
2747 * do a partial copy with NULL terminator.
2748 */
2749 char zero = '\0';
2750
2751 err = -ENOSPC;
2752 if (copy_to_user(ubuf, buf, input_len - 1))
2753 return -EFAULT;
2754 if (put_user(zero, ubuf + input_len - 1))
2755 return -EFAULT;
2756 }
2757 }
2758
2759 if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2760 put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2761 put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2762 put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2763 return -EFAULT;
2764
2765 return err;
2766 }
2767
2768 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2769
bpf_task_fd_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2770 static int bpf_task_fd_query(const union bpf_attr *attr,
2771 union bpf_attr __user *uattr)
2772 {
2773 pid_t pid = attr->task_fd_query.pid;
2774 u32 fd = attr->task_fd_query.fd;
2775 const struct perf_event *event;
2776 struct files_struct *files;
2777 struct task_struct *task;
2778 struct file *file;
2779 int err;
2780
2781 if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2782 return -EINVAL;
2783
2784 if (!capable(CAP_SYS_ADMIN))
2785 return -EPERM;
2786
2787 if (attr->task_fd_query.flags != 0)
2788 return -EINVAL;
2789
2790 rcu_read_lock();
2791 task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2792 rcu_read_unlock();
2793 if (!task)
2794 return -ENOENT;
2795
2796 files = get_files_struct(task);
2797 put_task_struct(task);
2798 if (!files)
2799 return -ENOENT;
2800
2801 err = 0;
2802 spin_lock(&files->file_lock);
2803 file = fcheck_files(files, fd);
2804 if (!file)
2805 err = -EBADF;
2806 else
2807 get_file(file);
2808 spin_unlock(&files->file_lock);
2809 put_files_struct(files);
2810
2811 if (err)
2812 goto out;
2813
2814 if (file->f_op == &bpf_raw_tp_fops) {
2815 struct bpf_raw_tracepoint *raw_tp = file->private_data;
2816 struct bpf_raw_event_map *btp = raw_tp->btp;
2817
2818 err = bpf_task_fd_query_copy(attr, uattr,
2819 raw_tp->prog->aux->id,
2820 BPF_FD_TYPE_RAW_TRACEPOINT,
2821 btp->tp->name, 0, 0);
2822 goto put_file;
2823 }
2824
2825 event = perf_get_event(file);
2826 if (!IS_ERR(event)) {
2827 u64 probe_offset, probe_addr;
2828 u32 prog_id, fd_type;
2829 const char *buf;
2830
2831 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2832 &buf, &probe_offset,
2833 &probe_addr);
2834 if (!err)
2835 err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2836 fd_type, buf,
2837 probe_offset,
2838 probe_addr);
2839 goto put_file;
2840 }
2841
2842 err = -ENOTSUPP;
2843 put_file:
2844 fput(file);
2845 out:
2846 return err;
2847 }
2848
SYSCALL_DEFINE3(bpf,int,cmd,union bpf_attr __user *,uattr,unsigned int,size)2849 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2850 {
2851 union bpf_attr attr;
2852 int err;
2853
2854 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2855 return -EPERM;
2856
2857 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2858 if (err)
2859 return err;
2860 size = min_t(u32, size, sizeof(attr));
2861
2862 /* copy attributes from user space, may be less than sizeof(bpf_attr) */
2863 memset(&attr, 0, sizeof(attr));
2864 if (copy_from_user(&attr, uattr, size) != 0)
2865 return -EFAULT;
2866
2867 err = security_bpf(cmd, &attr, size);
2868 if (err < 0)
2869 return err;
2870
2871 switch (cmd) {
2872 case BPF_MAP_CREATE:
2873 err = map_create(&attr);
2874 break;
2875 case BPF_MAP_LOOKUP_ELEM:
2876 err = map_lookup_elem(&attr);
2877 break;
2878 case BPF_MAP_UPDATE_ELEM:
2879 err = map_update_elem(&attr);
2880 break;
2881 case BPF_MAP_DELETE_ELEM:
2882 err = map_delete_elem(&attr);
2883 break;
2884 case BPF_MAP_GET_NEXT_KEY:
2885 err = map_get_next_key(&attr);
2886 break;
2887 case BPF_MAP_FREEZE:
2888 err = map_freeze(&attr);
2889 break;
2890 case BPF_PROG_LOAD:
2891 err = bpf_prog_load(&attr, uattr);
2892 break;
2893 case BPF_OBJ_PIN:
2894 err = bpf_obj_pin(&attr);
2895 break;
2896 case BPF_OBJ_GET:
2897 err = bpf_obj_get(&attr);
2898 break;
2899 case BPF_PROG_ATTACH:
2900 err = bpf_prog_attach(&attr);
2901 break;
2902 case BPF_PROG_DETACH:
2903 err = bpf_prog_detach(&attr);
2904 break;
2905 case BPF_PROG_QUERY:
2906 err = bpf_prog_query(&attr, uattr);
2907 break;
2908 case BPF_PROG_TEST_RUN:
2909 err = bpf_prog_test_run(&attr, uattr);
2910 break;
2911 case BPF_PROG_GET_NEXT_ID:
2912 err = bpf_obj_get_next_id(&attr, uattr,
2913 &prog_idr, &prog_idr_lock);
2914 break;
2915 case BPF_MAP_GET_NEXT_ID:
2916 err = bpf_obj_get_next_id(&attr, uattr,
2917 &map_idr, &map_idr_lock);
2918 break;
2919 case BPF_BTF_GET_NEXT_ID:
2920 err = bpf_obj_get_next_id(&attr, uattr,
2921 &btf_idr, &btf_idr_lock);
2922 break;
2923 case BPF_PROG_GET_FD_BY_ID:
2924 err = bpf_prog_get_fd_by_id(&attr);
2925 break;
2926 case BPF_MAP_GET_FD_BY_ID:
2927 err = bpf_map_get_fd_by_id(&attr);
2928 break;
2929 case BPF_OBJ_GET_INFO_BY_FD:
2930 err = bpf_obj_get_info_by_fd(&attr, uattr);
2931 break;
2932 case BPF_RAW_TRACEPOINT_OPEN:
2933 err = bpf_raw_tracepoint_open(&attr);
2934 break;
2935 case BPF_BTF_LOAD:
2936 err = bpf_btf_load(&attr);
2937 break;
2938 case BPF_BTF_GET_FD_BY_ID:
2939 err = bpf_btf_get_fd_by_id(&attr);
2940 break;
2941 case BPF_TASK_FD_QUERY:
2942 err = bpf_task_fd_query(&attr, uattr);
2943 break;
2944 case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2945 err = map_lookup_and_delete_elem(&attr);
2946 break;
2947 default:
2948 err = -EINVAL;
2949 break;
2950 }
2951
2952 return err;
2953 }
2954