1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
3 * Copyright (c) 2016 Facebook
4 */
5 #include <linux/kernel.h>
6 #include <linux/types.h>
7 #include <linux/slab.h>
8 #include <linux/bpf.h>
9 #include <linux/bpf_perf_event.h>
10 #include <linux/btf.h>
11 #include <linux/filter.h>
12 #include <linux/uaccess.h>
13 #include <linux/ctype.h>
14 #include <linux/kprobes.h>
15 #include <linux/spinlock.h>
16 #include <linux/syscalls.h>
17 #include <linux/error-injection.h>
18 #include <linux/btf_ids.h>
19 #include <linux/bpf_lsm.h>
20 #include <linux/fprobe.h>
21 #include <linux/bsearch.h>
22 #include <linux/sort.h>
23 #include <linux/key.h>
24 #include <linux/verification.h>
25
26 #include <net/bpf_sk_storage.h>
27
28 #include <uapi/linux/bpf.h>
29 #include <uapi/linux/btf.h>
30
31 #include <asm/tlb.h>
32
33 #include "trace_probe.h"
34 #include "trace.h"
35
36 #define CREATE_TRACE_POINTS
37 #include "bpf_trace.h"
38
39 #define bpf_event_rcu_dereference(p) \
40 rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
41
42 #ifdef CONFIG_MODULES
43 struct bpf_trace_module {
44 struct module *module;
45 struct list_head list;
46 };
47
48 static LIST_HEAD(bpf_trace_modules);
49 static DEFINE_MUTEX(bpf_module_mutex);
50
bpf_get_raw_tracepoint_module(const char * name)51 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
52 {
53 struct bpf_raw_event_map *btp, *ret = NULL;
54 struct bpf_trace_module *btm;
55 unsigned int i;
56
57 mutex_lock(&bpf_module_mutex);
58 list_for_each_entry(btm, &bpf_trace_modules, list) {
59 for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
60 btp = &btm->module->bpf_raw_events[i];
61 if (!strcmp(btp->tp->name, name)) {
62 if (try_module_get(btm->module))
63 ret = btp;
64 goto out;
65 }
66 }
67 }
68 out:
69 mutex_unlock(&bpf_module_mutex);
70 return ret;
71 }
72 #else
bpf_get_raw_tracepoint_module(const char * name)73 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
74 {
75 return NULL;
76 }
77 #endif /* CONFIG_MODULES */
78
79 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
80 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
81
82 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
83 u64 flags, const struct btf **btf,
84 s32 *btf_id);
85 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
86 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
87
88 /**
89 * trace_call_bpf - invoke BPF program
90 * @call: tracepoint event
91 * @ctx: opaque context pointer
92 *
93 * kprobe handlers execute BPF programs via this helper.
94 * Can be used from static tracepoints in the future.
95 *
96 * Return: BPF programs always return an integer which is interpreted by
97 * kprobe handler as:
98 * 0 - return from kprobe (event is filtered out)
99 * 1 - store kprobe event into ring buffer
100 * Other values are reserved and currently alias to 1
101 */
trace_call_bpf(struct trace_event_call * call,void * ctx)102 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
103 {
104 unsigned int ret;
105
106 cant_sleep();
107
108 if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
109 /*
110 * since some bpf program is already running on this cpu,
111 * don't call into another bpf program (same or different)
112 * and don't send kprobe event into ring-buffer,
113 * so return zero here
114 */
115 ret = 0;
116 goto out;
117 }
118
119 /*
120 * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
121 * to all call sites, we did a bpf_prog_array_valid() there to check
122 * whether call->prog_array is empty or not, which is
123 * a heuristic to speed up execution.
124 *
125 * If bpf_prog_array_valid() fetched prog_array was
126 * non-NULL, we go into trace_call_bpf() and do the actual
127 * proper rcu_dereference() under RCU lock.
128 * If it turns out that prog_array is NULL then, we bail out.
129 * For the opposite, if the bpf_prog_array_valid() fetched pointer
130 * was NULL, you'll skip the prog_array with the risk of missing
131 * out of events when it was updated in between this and the
132 * rcu_dereference() which is accepted risk.
133 */
134 rcu_read_lock();
135 ret = bpf_prog_run_array(rcu_dereference(call->prog_array),
136 ctx, bpf_prog_run);
137 rcu_read_unlock();
138
139 out:
140 __this_cpu_dec(bpf_prog_active);
141
142 return ret;
143 }
144
145 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
BPF_CALL_2(bpf_override_return,struct pt_regs *,regs,unsigned long,rc)146 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
147 {
148 regs_set_return_value(regs, rc);
149 override_function_with_return(regs);
150 return 0;
151 }
152
153 static const struct bpf_func_proto bpf_override_return_proto = {
154 .func = bpf_override_return,
155 .gpl_only = true,
156 .ret_type = RET_INTEGER,
157 .arg1_type = ARG_PTR_TO_CTX,
158 .arg2_type = ARG_ANYTHING,
159 };
160 #endif
161
162 static __always_inline int
bpf_probe_read_user_common(void * dst,u32 size,const void __user * unsafe_ptr)163 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
164 {
165 int ret;
166
167 ret = copy_from_user_nofault(dst, unsafe_ptr, size);
168 if (unlikely(ret < 0))
169 memset(dst, 0, size);
170 return ret;
171 }
172
BPF_CALL_3(bpf_probe_read_user,void *,dst,u32,size,const void __user *,unsafe_ptr)173 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
174 const void __user *, unsafe_ptr)
175 {
176 return bpf_probe_read_user_common(dst, size, unsafe_ptr);
177 }
178
179 const struct bpf_func_proto bpf_probe_read_user_proto = {
180 .func = bpf_probe_read_user,
181 .gpl_only = true,
182 .ret_type = RET_INTEGER,
183 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
184 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
185 .arg3_type = ARG_ANYTHING,
186 };
187
188 static __always_inline int
bpf_probe_read_user_str_common(void * dst,u32 size,const void __user * unsafe_ptr)189 bpf_probe_read_user_str_common(void *dst, u32 size,
190 const void __user *unsafe_ptr)
191 {
192 int ret;
193
194 /*
195 * NB: We rely on strncpy_from_user() not copying junk past the NUL
196 * terminator into `dst`.
197 *
198 * strncpy_from_user() does long-sized strides in the fast path. If the
199 * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
200 * then there could be junk after the NUL in `dst`. If user takes `dst`
201 * and keys a hash map with it, then semantically identical strings can
202 * occupy multiple entries in the map.
203 */
204 ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
205 if (unlikely(ret < 0))
206 memset(dst, 0, size);
207 return ret;
208 }
209
BPF_CALL_3(bpf_probe_read_user_str,void *,dst,u32,size,const void __user *,unsafe_ptr)210 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
211 const void __user *, unsafe_ptr)
212 {
213 return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
214 }
215
216 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
217 .func = bpf_probe_read_user_str,
218 .gpl_only = true,
219 .ret_type = RET_INTEGER,
220 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
221 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
222 .arg3_type = ARG_ANYTHING,
223 };
224
225 static __always_inline int
bpf_probe_read_kernel_common(void * dst,u32 size,const void * unsafe_ptr)226 bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
227 {
228 int ret;
229
230 ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
231 if (unlikely(ret < 0))
232 memset(dst, 0, size);
233 return ret;
234 }
235
BPF_CALL_3(bpf_probe_read_kernel,void *,dst,u32,size,const void *,unsafe_ptr)236 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
237 const void *, unsafe_ptr)
238 {
239 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
240 }
241
242 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
243 .func = bpf_probe_read_kernel,
244 .gpl_only = true,
245 .ret_type = RET_INTEGER,
246 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
247 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
248 .arg3_type = ARG_ANYTHING,
249 };
250
251 static __always_inline int
bpf_probe_read_kernel_str_common(void * dst,u32 size,const void * unsafe_ptr)252 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
253 {
254 int ret;
255
256 /*
257 * The strncpy_from_kernel_nofault() call will likely not fill the
258 * entire buffer, but that's okay in this circumstance as we're probing
259 * arbitrary memory anyway similar to bpf_probe_read_*() and might
260 * as well probe the stack. Thus, memory is explicitly cleared
261 * only in error case, so that improper users ignoring return
262 * code altogether don't copy garbage; otherwise length of string
263 * is returned that can be used for bpf_perf_event_output() et al.
264 */
265 ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
266 if (unlikely(ret < 0))
267 memset(dst, 0, size);
268 return ret;
269 }
270
BPF_CALL_3(bpf_probe_read_kernel_str,void *,dst,u32,size,const void *,unsafe_ptr)271 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
272 const void *, unsafe_ptr)
273 {
274 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
275 }
276
277 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
278 .func = bpf_probe_read_kernel_str,
279 .gpl_only = true,
280 .ret_type = RET_INTEGER,
281 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
282 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
283 .arg3_type = ARG_ANYTHING,
284 };
285
286 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
BPF_CALL_3(bpf_probe_read_compat,void *,dst,u32,size,const void *,unsafe_ptr)287 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
288 const void *, unsafe_ptr)
289 {
290 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
291 return bpf_probe_read_user_common(dst, size,
292 (__force void __user *)unsafe_ptr);
293 }
294 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
295 }
296
297 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
298 .func = bpf_probe_read_compat,
299 .gpl_only = true,
300 .ret_type = RET_INTEGER,
301 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
302 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
303 .arg3_type = ARG_ANYTHING,
304 };
305
BPF_CALL_3(bpf_probe_read_compat_str,void *,dst,u32,size,const void *,unsafe_ptr)306 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
307 const void *, unsafe_ptr)
308 {
309 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
310 return bpf_probe_read_user_str_common(dst, size,
311 (__force void __user *)unsafe_ptr);
312 }
313 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
314 }
315
316 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
317 .func = bpf_probe_read_compat_str,
318 .gpl_only = true,
319 .ret_type = RET_INTEGER,
320 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
321 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
322 .arg3_type = ARG_ANYTHING,
323 };
324 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
325
BPF_CALL_3(bpf_probe_write_user,void __user *,unsafe_ptr,const void *,src,u32,size)326 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
327 u32, size)
328 {
329 /*
330 * Ensure we're in user context which is safe for the helper to
331 * run. This helper has no business in a kthread.
332 *
333 * access_ok() should prevent writing to non-user memory, but in
334 * some situations (nommu, temporary switch, etc) access_ok() does
335 * not provide enough validation, hence the check on KERNEL_DS.
336 *
337 * nmi_uaccess_okay() ensures the probe is not run in an interim
338 * state, when the task or mm are switched. This is specifically
339 * required to prevent the use of temporary mm.
340 */
341
342 if (unlikely(in_interrupt() ||
343 current->flags & (PF_KTHREAD | PF_EXITING)))
344 return -EPERM;
345 if (unlikely(!nmi_uaccess_okay()))
346 return -EPERM;
347
348 return copy_to_user_nofault(unsafe_ptr, src, size);
349 }
350
351 static const struct bpf_func_proto bpf_probe_write_user_proto = {
352 .func = bpf_probe_write_user,
353 .gpl_only = true,
354 .ret_type = RET_INTEGER,
355 .arg1_type = ARG_ANYTHING,
356 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
357 .arg3_type = ARG_CONST_SIZE,
358 };
359
bpf_get_probe_write_proto(void)360 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
361 {
362 if (!capable(CAP_SYS_ADMIN))
363 return NULL;
364
365 pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
366 current->comm, task_pid_nr(current));
367
368 return &bpf_probe_write_user_proto;
369 }
370
371 #define MAX_TRACE_PRINTK_VARARGS 3
372 #define BPF_TRACE_PRINTK_SIZE 1024
373
BPF_CALL_5(bpf_trace_printk,char *,fmt,u32,fmt_size,u64,arg1,u64,arg2,u64,arg3)374 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
375 u64, arg2, u64, arg3)
376 {
377 u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
378 struct bpf_bprintf_data data = {
379 .get_bin_args = true,
380 .get_buf = true,
381 };
382 int ret;
383
384 ret = bpf_bprintf_prepare(fmt, fmt_size, args,
385 MAX_TRACE_PRINTK_VARARGS, &data);
386 if (ret < 0)
387 return ret;
388
389 ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
390
391 trace_bpf_trace_printk(data.buf);
392
393 bpf_bprintf_cleanup(&data);
394
395 return ret;
396 }
397
398 static const struct bpf_func_proto bpf_trace_printk_proto = {
399 .func = bpf_trace_printk,
400 .gpl_only = true,
401 .ret_type = RET_INTEGER,
402 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY,
403 .arg2_type = ARG_CONST_SIZE,
404 };
405
__set_printk_clr_event(void)406 static void __set_printk_clr_event(void)
407 {
408 /*
409 * This program might be calling bpf_trace_printk,
410 * so enable the associated bpf_trace/bpf_trace_printk event.
411 * Repeat this each time as it is possible a user has
412 * disabled bpf_trace_printk events. By loading a program
413 * calling bpf_trace_printk() however the user has expressed
414 * the intent to see such events.
415 */
416 if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
417 pr_warn_ratelimited("could not enable bpf_trace_printk events");
418 }
419
bpf_get_trace_printk_proto(void)420 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
421 {
422 __set_printk_clr_event();
423 return &bpf_trace_printk_proto;
424 }
425
BPF_CALL_4(bpf_trace_vprintk,char *,fmt,u32,fmt_size,const void *,args,u32,data_len)426 BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, args,
427 u32, data_len)
428 {
429 struct bpf_bprintf_data data = {
430 .get_bin_args = true,
431 .get_buf = true,
432 };
433 int ret, num_args;
434
435 if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
436 (data_len && !args))
437 return -EINVAL;
438 num_args = data_len / 8;
439
440 ret = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
441 if (ret < 0)
442 return ret;
443
444 ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
445
446 trace_bpf_trace_printk(data.buf);
447
448 bpf_bprintf_cleanup(&data);
449
450 return ret;
451 }
452
453 static const struct bpf_func_proto bpf_trace_vprintk_proto = {
454 .func = bpf_trace_vprintk,
455 .gpl_only = true,
456 .ret_type = RET_INTEGER,
457 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY,
458 .arg2_type = ARG_CONST_SIZE,
459 .arg3_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
460 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
461 };
462
bpf_get_trace_vprintk_proto(void)463 const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
464 {
465 __set_printk_clr_event();
466 return &bpf_trace_vprintk_proto;
467 }
468
BPF_CALL_5(bpf_seq_printf,struct seq_file *,m,char *,fmt,u32,fmt_size,const void *,args,u32,data_len)469 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
470 const void *, args, u32, data_len)
471 {
472 struct bpf_bprintf_data data = {
473 .get_bin_args = true,
474 };
475 int err, num_args;
476
477 if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
478 (data_len && !args))
479 return -EINVAL;
480 num_args = data_len / 8;
481
482 err = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
483 if (err < 0)
484 return err;
485
486 seq_bprintf(m, fmt, data.bin_args);
487
488 bpf_bprintf_cleanup(&data);
489
490 return seq_has_overflowed(m) ? -EOVERFLOW : 0;
491 }
492
493 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
494
495 static const struct bpf_func_proto bpf_seq_printf_proto = {
496 .func = bpf_seq_printf,
497 .gpl_only = true,
498 .ret_type = RET_INTEGER,
499 .arg1_type = ARG_PTR_TO_BTF_ID,
500 .arg1_btf_id = &btf_seq_file_ids[0],
501 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
502 .arg3_type = ARG_CONST_SIZE,
503 .arg4_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
504 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
505 };
506
BPF_CALL_3(bpf_seq_write,struct seq_file *,m,const void *,data,u32,len)507 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
508 {
509 return seq_write(m, data, len) ? -EOVERFLOW : 0;
510 }
511
512 static const struct bpf_func_proto bpf_seq_write_proto = {
513 .func = bpf_seq_write,
514 .gpl_only = true,
515 .ret_type = RET_INTEGER,
516 .arg1_type = ARG_PTR_TO_BTF_ID,
517 .arg1_btf_id = &btf_seq_file_ids[0],
518 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
519 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
520 };
521
BPF_CALL_4(bpf_seq_printf_btf,struct seq_file *,m,struct btf_ptr *,ptr,u32,btf_ptr_size,u64,flags)522 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
523 u32, btf_ptr_size, u64, flags)
524 {
525 const struct btf *btf;
526 s32 btf_id;
527 int ret;
528
529 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
530 if (ret)
531 return ret;
532
533 return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
534 }
535
536 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
537 .func = bpf_seq_printf_btf,
538 .gpl_only = true,
539 .ret_type = RET_INTEGER,
540 .arg1_type = ARG_PTR_TO_BTF_ID,
541 .arg1_btf_id = &btf_seq_file_ids[0],
542 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
543 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
544 .arg4_type = ARG_ANYTHING,
545 };
546
547 static __always_inline int
get_map_perf_counter(struct bpf_map * map,u64 flags,u64 * value,u64 * enabled,u64 * running)548 get_map_perf_counter(struct bpf_map *map, u64 flags,
549 u64 *value, u64 *enabled, u64 *running)
550 {
551 struct bpf_array *array = container_of(map, struct bpf_array, map);
552 unsigned int cpu = smp_processor_id();
553 u64 index = flags & BPF_F_INDEX_MASK;
554 struct bpf_event_entry *ee;
555
556 if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
557 return -EINVAL;
558 if (index == BPF_F_CURRENT_CPU)
559 index = cpu;
560 if (unlikely(index >= array->map.max_entries))
561 return -E2BIG;
562
563 ee = READ_ONCE(array->ptrs[index]);
564 if (!ee)
565 return -ENOENT;
566
567 return perf_event_read_local(ee->event, value, enabled, running);
568 }
569
BPF_CALL_2(bpf_perf_event_read,struct bpf_map *,map,u64,flags)570 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
571 {
572 u64 value = 0;
573 int err;
574
575 err = get_map_perf_counter(map, flags, &value, NULL, NULL);
576 /*
577 * this api is ugly since we miss [-22..-2] range of valid
578 * counter values, but that's uapi
579 */
580 if (err)
581 return err;
582 return value;
583 }
584
585 static const struct bpf_func_proto bpf_perf_event_read_proto = {
586 .func = bpf_perf_event_read,
587 .gpl_only = true,
588 .ret_type = RET_INTEGER,
589 .arg1_type = ARG_CONST_MAP_PTR,
590 .arg2_type = ARG_ANYTHING,
591 };
592
BPF_CALL_4(bpf_perf_event_read_value,struct bpf_map *,map,u64,flags,struct bpf_perf_event_value *,buf,u32,size)593 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
594 struct bpf_perf_event_value *, buf, u32, size)
595 {
596 int err = -EINVAL;
597
598 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
599 goto clear;
600 err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
601 &buf->running);
602 if (unlikely(err))
603 goto clear;
604 return 0;
605 clear:
606 memset(buf, 0, size);
607 return err;
608 }
609
610 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
611 .func = bpf_perf_event_read_value,
612 .gpl_only = true,
613 .ret_type = RET_INTEGER,
614 .arg1_type = ARG_CONST_MAP_PTR,
615 .arg2_type = ARG_ANYTHING,
616 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
617 .arg4_type = ARG_CONST_SIZE,
618 };
619
620 static __always_inline u64
__bpf_perf_event_output(struct pt_regs * regs,struct bpf_map * map,u64 flags,struct perf_sample_data * sd)621 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
622 u64 flags, struct perf_sample_data *sd)
623 {
624 struct bpf_array *array = container_of(map, struct bpf_array, map);
625 unsigned int cpu = smp_processor_id();
626 u64 index = flags & BPF_F_INDEX_MASK;
627 struct bpf_event_entry *ee;
628 struct perf_event *event;
629
630 if (index == BPF_F_CURRENT_CPU)
631 index = cpu;
632 if (unlikely(index >= array->map.max_entries))
633 return -E2BIG;
634
635 ee = READ_ONCE(array->ptrs[index]);
636 if (!ee)
637 return -ENOENT;
638
639 event = ee->event;
640 if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
641 event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
642 return -EINVAL;
643
644 if (unlikely(event->oncpu != cpu))
645 return -EOPNOTSUPP;
646
647 return perf_event_output(event, sd, regs);
648 }
649
650 /*
651 * Support executing tracepoints in normal, irq, and nmi context that each call
652 * bpf_perf_event_output
653 */
654 struct bpf_trace_sample_data {
655 struct perf_sample_data sds[3];
656 };
657
658 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
659 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
BPF_CALL_5(bpf_perf_event_output,struct pt_regs *,regs,struct bpf_map *,map,u64,flags,void *,data,u64,size)660 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
661 u64, flags, void *, data, u64, size)
662 {
663 struct bpf_trace_sample_data *sds;
664 struct perf_raw_record raw = {
665 .frag = {
666 .size = size,
667 .data = data,
668 },
669 };
670 struct perf_sample_data *sd;
671 int nest_level, err;
672
673 preempt_disable();
674 sds = this_cpu_ptr(&bpf_trace_sds);
675 nest_level = this_cpu_inc_return(bpf_trace_nest_level);
676
677 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
678 err = -EBUSY;
679 goto out;
680 }
681
682 sd = &sds->sds[nest_level - 1];
683
684 if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
685 err = -EINVAL;
686 goto out;
687 }
688
689 perf_sample_data_init(sd, 0, 0);
690 sd->raw = &raw;
691 sd->sample_flags |= PERF_SAMPLE_RAW;
692
693 err = __bpf_perf_event_output(regs, map, flags, sd);
694 out:
695 this_cpu_dec(bpf_trace_nest_level);
696 preempt_enable();
697 return err;
698 }
699
700 static const struct bpf_func_proto bpf_perf_event_output_proto = {
701 .func = bpf_perf_event_output,
702 .gpl_only = true,
703 .ret_type = RET_INTEGER,
704 .arg1_type = ARG_PTR_TO_CTX,
705 .arg2_type = ARG_CONST_MAP_PTR,
706 .arg3_type = ARG_ANYTHING,
707 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
708 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
709 };
710
711 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
712 struct bpf_nested_pt_regs {
713 struct pt_regs regs[3];
714 };
715 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
716 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
717
bpf_event_output(struct bpf_map * map,u64 flags,void * meta,u64 meta_size,void * ctx,u64 ctx_size,bpf_ctx_copy_t ctx_copy)718 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
719 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
720 {
721 struct perf_raw_frag frag = {
722 .copy = ctx_copy,
723 .size = ctx_size,
724 .data = ctx,
725 };
726 struct perf_raw_record raw = {
727 .frag = {
728 {
729 .next = ctx_size ? &frag : NULL,
730 },
731 .size = meta_size,
732 .data = meta,
733 },
734 };
735 struct perf_sample_data *sd;
736 struct pt_regs *regs;
737 int nest_level;
738 u64 ret;
739
740 preempt_disable();
741 nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
742
743 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
744 ret = -EBUSY;
745 goto out;
746 }
747 sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
748 regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
749
750 perf_fetch_caller_regs(regs);
751 perf_sample_data_init(sd, 0, 0);
752 sd->raw = &raw;
753 sd->sample_flags |= PERF_SAMPLE_RAW;
754
755 ret = __bpf_perf_event_output(regs, map, flags, sd);
756 out:
757 this_cpu_dec(bpf_event_output_nest_level);
758 preempt_enable();
759 return ret;
760 }
761
BPF_CALL_0(bpf_get_current_task)762 BPF_CALL_0(bpf_get_current_task)
763 {
764 return (long) current;
765 }
766
767 const struct bpf_func_proto bpf_get_current_task_proto = {
768 .func = bpf_get_current_task,
769 .gpl_only = true,
770 .ret_type = RET_INTEGER,
771 };
772
BPF_CALL_0(bpf_get_current_task_btf)773 BPF_CALL_0(bpf_get_current_task_btf)
774 {
775 return (unsigned long) current;
776 }
777
778 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
779 .func = bpf_get_current_task_btf,
780 .gpl_only = true,
781 .ret_type = RET_PTR_TO_BTF_ID,
782 .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
783 };
784
BPF_CALL_1(bpf_task_pt_regs,struct task_struct *,task)785 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
786 {
787 return (unsigned long) task_pt_regs(task);
788 }
789
790 BTF_ID_LIST(bpf_task_pt_regs_ids)
791 BTF_ID(struct, pt_regs)
792
793 const struct bpf_func_proto bpf_task_pt_regs_proto = {
794 .func = bpf_task_pt_regs,
795 .gpl_only = true,
796 .arg1_type = ARG_PTR_TO_BTF_ID,
797 .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
798 .ret_type = RET_PTR_TO_BTF_ID,
799 .ret_btf_id = &bpf_task_pt_regs_ids[0],
800 };
801
BPF_CALL_2(bpf_current_task_under_cgroup,struct bpf_map *,map,u32,idx)802 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
803 {
804 struct bpf_array *array = container_of(map, struct bpf_array, map);
805 struct cgroup *cgrp;
806
807 if (unlikely(idx >= array->map.max_entries))
808 return -E2BIG;
809
810 cgrp = READ_ONCE(array->ptrs[idx]);
811 if (unlikely(!cgrp))
812 return -EAGAIN;
813
814 return task_under_cgroup_hierarchy(current, cgrp);
815 }
816
817 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
818 .func = bpf_current_task_under_cgroup,
819 .gpl_only = false,
820 .ret_type = RET_INTEGER,
821 .arg1_type = ARG_CONST_MAP_PTR,
822 .arg2_type = ARG_ANYTHING,
823 };
824
825 struct send_signal_irq_work {
826 struct irq_work irq_work;
827 struct task_struct *task;
828 u32 sig;
829 enum pid_type type;
830 };
831
832 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
833
do_bpf_send_signal(struct irq_work * entry)834 static void do_bpf_send_signal(struct irq_work *entry)
835 {
836 struct send_signal_irq_work *work;
837
838 work = container_of(entry, struct send_signal_irq_work, irq_work);
839 group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
840 put_task_struct(work->task);
841 }
842
bpf_send_signal_common(u32 sig,enum pid_type type)843 static int bpf_send_signal_common(u32 sig, enum pid_type type)
844 {
845 struct send_signal_irq_work *work = NULL;
846
847 /* Similar to bpf_probe_write_user, task needs to be
848 * in a sound condition and kernel memory access be
849 * permitted in order to send signal to the current
850 * task.
851 */
852 if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
853 return -EPERM;
854 if (unlikely(!nmi_uaccess_okay()))
855 return -EPERM;
856 /* Task should not be pid=1 to avoid kernel panic. */
857 if (unlikely(is_global_init(current)))
858 return -EPERM;
859
860 if (irqs_disabled()) {
861 /* Do an early check on signal validity. Otherwise,
862 * the error is lost in deferred irq_work.
863 */
864 if (unlikely(!valid_signal(sig)))
865 return -EINVAL;
866
867 work = this_cpu_ptr(&send_signal_work);
868 if (irq_work_is_busy(&work->irq_work))
869 return -EBUSY;
870
871 /* Add the current task, which is the target of sending signal,
872 * to the irq_work. The current task may change when queued
873 * irq works get executed.
874 */
875 work->task = get_task_struct(current);
876 work->sig = sig;
877 work->type = type;
878 irq_work_queue(&work->irq_work);
879 return 0;
880 }
881
882 return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
883 }
884
BPF_CALL_1(bpf_send_signal,u32,sig)885 BPF_CALL_1(bpf_send_signal, u32, sig)
886 {
887 return bpf_send_signal_common(sig, PIDTYPE_TGID);
888 }
889
890 static const struct bpf_func_proto bpf_send_signal_proto = {
891 .func = bpf_send_signal,
892 .gpl_only = false,
893 .ret_type = RET_INTEGER,
894 .arg1_type = ARG_ANYTHING,
895 };
896
BPF_CALL_1(bpf_send_signal_thread,u32,sig)897 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
898 {
899 return bpf_send_signal_common(sig, PIDTYPE_PID);
900 }
901
902 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
903 .func = bpf_send_signal_thread,
904 .gpl_only = false,
905 .ret_type = RET_INTEGER,
906 .arg1_type = ARG_ANYTHING,
907 };
908
BPF_CALL_3(bpf_d_path,struct path *,path,char *,buf,u32,sz)909 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
910 {
911 struct path copy;
912 long len;
913 char *p;
914
915 if (!sz)
916 return 0;
917
918 /*
919 * The path pointer is verified as trusted and safe to use,
920 * but let's double check it's valid anyway to workaround
921 * potentially broken verifier.
922 */
923 len = copy_from_kernel_nofault(©, path, sizeof(*path));
924 if (len < 0)
925 return len;
926
927 p = d_path(©, buf, sz);
928 if (IS_ERR(p)) {
929 len = PTR_ERR(p);
930 } else {
931 len = buf + sz - p;
932 memmove(buf, p, len);
933 }
934
935 return len;
936 }
937
938 BTF_SET_START(btf_allowlist_d_path)
939 #ifdef CONFIG_SECURITY
BTF_ID(func,security_file_permission)940 BTF_ID(func, security_file_permission)
941 BTF_ID(func, security_inode_getattr)
942 BTF_ID(func, security_file_open)
943 #endif
944 #ifdef CONFIG_SECURITY_PATH
945 BTF_ID(func, security_path_truncate)
946 #endif
947 BTF_ID(func, vfs_truncate)
948 BTF_ID(func, vfs_fallocate)
949 BTF_ID(func, dentry_open)
950 BTF_ID(func, vfs_getattr)
951 BTF_ID(func, filp_close)
952 BTF_SET_END(btf_allowlist_d_path)
953
954 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
955 {
956 if (prog->type == BPF_PROG_TYPE_TRACING &&
957 prog->expected_attach_type == BPF_TRACE_ITER)
958 return true;
959
960 if (prog->type == BPF_PROG_TYPE_LSM)
961 return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
962
963 return btf_id_set_contains(&btf_allowlist_d_path,
964 prog->aux->attach_btf_id);
965 }
966
967 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
968
969 static const struct bpf_func_proto bpf_d_path_proto = {
970 .func = bpf_d_path,
971 .gpl_only = false,
972 .ret_type = RET_INTEGER,
973 .arg1_type = ARG_PTR_TO_BTF_ID,
974 .arg1_btf_id = &bpf_d_path_btf_ids[0],
975 .arg2_type = ARG_PTR_TO_MEM,
976 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
977 .allowed = bpf_d_path_allowed,
978 };
979
980 #define BTF_F_ALL (BTF_F_COMPACT | BTF_F_NONAME | \
981 BTF_F_PTR_RAW | BTF_F_ZERO)
982
bpf_btf_printf_prepare(struct btf_ptr * ptr,u32 btf_ptr_size,u64 flags,const struct btf ** btf,s32 * btf_id)983 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
984 u64 flags, const struct btf **btf,
985 s32 *btf_id)
986 {
987 const struct btf_type *t;
988
989 if (unlikely(flags & ~(BTF_F_ALL)))
990 return -EINVAL;
991
992 if (btf_ptr_size != sizeof(struct btf_ptr))
993 return -EINVAL;
994
995 *btf = bpf_get_btf_vmlinux();
996
997 if (IS_ERR_OR_NULL(*btf))
998 return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
999
1000 if (ptr->type_id > 0)
1001 *btf_id = ptr->type_id;
1002 else
1003 return -EINVAL;
1004
1005 if (*btf_id > 0)
1006 t = btf_type_by_id(*btf, *btf_id);
1007 if (*btf_id <= 0 || !t)
1008 return -ENOENT;
1009
1010 return 0;
1011 }
1012
BPF_CALL_5(bpf_snprintf_btf,char *,str,u32,str_size,struct btf_ptr *,ptr,u32,btf_ptr_size,u64,flags)1013 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
1014 u32, btf_ptr_size, u64, flags)
1015 {
1016 const struct btf *btf;
1017 s32 btf_id;
1018 int ret;
1019
1020 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
1021 if (ret)
1022 return ret;
1023
1024 return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
1025 flags);
1026 }
1027
1028 const struct bpf_func_proto bpf_snprintf_btf_proto = {
1029 .func = bpf_snprintf_btf,
1030 .gpl_only = false,
1031 .ret_type = RET_INTEGER,
1032 .arg1_type = ARG_PTR_TO_MEM,
1033 .arg2_type = ARG_CONST_SIZE,
1034 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1035 .arg4_type = ARG_CONST_SIZE,
1036 .arg5_type = ARG_ANYTHING,
1037 };
1038
BPF_CALL_1(bpf_get_func_ip_tracing,void *,ctx)1039 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
1040 {
1041 /* This helper call is inlined by verifier. */
1042 return ((u64 *)ctx)[-2];
1043 }
1044
1045 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
1046 .func = bpf_get_func_ip_tracing,
1047 .gpl_only = true,
1048 .ret_type = RET_INTEGER,
1049 .arg1_type = ARG_PTR_TO_CTX,
1050 };
1051
1052 #ifdef CONFIG_X86_KERNEL_IBT
get_entry_ip(unsigned long fentry_ip)1053 static unsigned long get_entry_ip(unsigned long fentry_ip)
1054 {
1055 u32 instr;
1056
1057 /* Being extra safe in here in case entry ip is on the page-edge. */
1058 if (get_kernel_nofault(instr, (u32 *) fentry_ip - 1))
1059 return fentry_ip;
1060 if (is_endbr(instr))
1061 fentry_ip -= ENDBR_INSN_SIZE;
1062 return fentry_ip;
1063 }
1064 #else
1065 #define get_entry_ip(fentry_ip) fentry_ip
1066 #endif
1067
BPF_CALL_1(bpf_get_func_ip_kprobe,struct pt_regs *,regs)1068 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
1069 {
1070 struct kprobe *kp = kprobe_running();
1071
1072 if (!kp || !(kp->flags & KPROBE_FLAG_ON_FUNC_ENTRY))
1073 return 0;
1074
1075 return get_entry_ip((uintptr_t)kp->addr);
1076 }
1077
1078 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
1079 .func = bpf_get_func_ip_kprobe,
1080 .gpl_only = true,
1081 .ret_type = RET_INTEGER,
1082 .arg1_type = ARG_PTR_TO_CTX,
1083 };
1084
BPF_CALL_1(bpf_get_func_ip_kprobe_multi,struct pt_regs *,regs)1085 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
1086 {
1087 return bpf_kprobe_multi_entry_ip(current->bpf_ctx);
1088 }
1089
1090 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
1091 .func = bpf_get_func_ip_kprobe_multi,
1092 .gpl_only = false,
1093 .ret_type = RET_INTEGER,
1094 .arg1_type = ARG_PTR_TO_CTX,
1095 };
1096
BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi,struct pt_regs *,regs)1097 BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs)
1098 {
1099 return bpf_kprobe_multi_cookie(current->bpf_ctx);
1100 }
1101
1102 static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
1103 .func = bpf_get_attach_cookie_kprobe_multi,
1104 .gpl_only = false,
1105 .ret_type = RET_INTEGER,
1106 .arg1_type = ARG_PTR_TO_CTX,
1107 };
1108
BPF_CALL_1(bpf_get_attach_cookie_trace,void *,ctx)1109 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
1110 {
1111 struct bpf_trace_run_ctx *run_ctx;
1112
1113 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1114 return run_ctx->bpf_cookie;
1115 }
1116
1117 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
1118 .func = bpf_get_attach_cookie_trace,
1119 .gpl_only = false,
1120 .ret_type = RET_INTEGER,
1121 .arg1_type = ARG_PTR_TO_CTX,
1122 };
1123
BPF_CALL_1(bpf_get_attach_cookie_pe,struct bpf_perf_event_data_kern *,ctx)1124 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
1125 {
1126 return ctx->event->bpf_cookie;
1127 }
1128
1129 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
1130 .func = bpf_get_attach_cookie_pe,
1131 .gpl_only = false,
1132 .ret_type = RET_INTEGER,
1133 .arg1_type = ARG_PTR_TO_CTX,
1134 };
1135
BPF_CALL_1(bpf_get_attach_cookie_tracing,void *,ctx)1136 BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx)
1137 {
1138 struct bpf_trace_run_ctx *run_ctx;
1139
1140 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1141 return run_ctx->bpf_cookie;
1142 }
1143
1144 static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = {
1145 .func = bpf_get_attach_cookie_tracing,
1146 .gpl_only = false,
1147 .ret_type = RET_INTEGER,
1148 .arg1_type = ARG_PTR_TO_CTX,
1149 };
1150
BPF_CALL_3(bpf_get_branch_snapshot,void *,buf,u32,size,u64,flags)1151 BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
1152 {
1153 #ifndef CONFIG_X86
1154 return -ENOENT;
1155 #else
1156 static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1157 u32 entry_cnt = size / br_entry_size;
1158
1159 entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
1160
1161 if (unlikely(flags))
1162 return -EINVAL;
1163
1164 if (!entry_cnt)
1165 return -ENOENT;
1166
1167 return entry_cnt * br_entry_size;
1168 #endif
1169 }
1170
1171 static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
1172 .func = bpf_get_branch_snapshot,
1173 .gpl_only = true,
1174 .ret_type = RET_INTEGER,
1175 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
1176 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
1177 };
1178
BPF_CALL_3(get_func_arg,void *,ctx,u32,n,u64 *,value)1179 BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
1180 {
1181 /* This helper call is inlined by verifier. */
1182 u64 nr_args = ((u64 *)ctx)[-1];
1183
1184 if ((u64) n >= nr_args)
1185 return -EINVAL;
1186 *value = ((u64 *)ctx)[n];
1187 return 0;
1188 }
1189
1190 static const struct bpf_func_proto bpf_get_func_arg_proto = {
1191 .func = get_func_arg,
1192 .ret_type = RET_INTEGER,
1193 .arg1_type = ARG_PTR_TO_CTX,
1194 .arg2_type = ARG_ANYTHING,
1195 .arg3_type = ARG_PTR_TO_LONG,
1196 };
1197
BPF_CALL_2(get_func_ret,void *,ctx,u64 *,value)1198 BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
1199 {
1200 /* This helper call is inlined by verifier. */
1201 u64 nr_args = ((u64 *)ctx)[-1];
1202
1203 *value = ((u64 *)ctx)[nr_args];
1204 return 0;
1205 }
1206
1207 static const struct bpf_func_proto bpf_get_func_ret_proto = {
1208 .func = get_func_ret,
1209 .ret_type = RET_INTEGER,
1210 .arg1_type = ARG_PTR_TO_CTX,
1211 .arg2_type = ARG_PTR_TO_LONG,
1212 };
1213
BPF_CALL_1(get_func_arg_cnt,void *,ctx)1214 BPF_CALL_1(get_func_arg_cnt, void *, ctx)
1215 {
1216 /* This helper call is inlined by verifier. */
1217 return ((u64 *)ctx)[-1];
1218 }
1219
1220 static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
1221 .func = get_func_arg_cnt,
1222 .ret_type = RET_INTEGER,
1223 .arg1_type = ARG_PTR_TO_CTX,
1224 };
1225
1226 #ifdef CONFIG_KEYS
1227 __diag_push();
1228 __diag_ignore_all("-Wmissing-prototypes",
1229 "kfuncs which will be used in BPF programs");
1230
1231 /**
1232 * bpf_lookup_user_key - lookup a key by its serial
1233 * @serial: key handle serial number
1234 * @flags: lookup-specific flags
1235 *
1236 * Search a key with a given *serial* and the provided *flags*.
1237 * If found, increment the reference count of the key by one, and
1238 * return it in the bpf_key structure.
1239 *
1240 * The bpf_key structure must be passed to bpf_key_put() when done
1241 * with it, so that the key reference count is decremented and the
1242 * bpf_key structure is freed.
1243 *
1244 * Permission checks are deferred to the time the key is used by
1245 * one of the available key-specific kfuncs.
1246 *
1247 * Set *flags* with KEY_LOOKUP_CREATE, to attempt creating a requested
1248 * special keyring (e.g. session keyring), if it doesn't yet exist.
1249 * Set *flags* with KEY_LOOKUP_PARTIAL, to lookup a key without waiting
1250 * for the key construction, and to retrieve uninstantiated keys (keys
1251 * without data attached to them).
1252 *
1253 * Return: a bpf_key pointer with a valid key pointer if the key is found, a
1254 * NULL pointer otherwise.
1255 */
bpf_lookup_user_key(u32 serial,u64 flags)1256 struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
1257 {
1258 key_ref_t key_ref;
1259 struct bpf_key *bkey;
1260
1261 if (flags & ~KEY_LOOKUP_ALL)
1262 return NULL;
1263
1264 /*
1265 * Permission check is deferred until the key is used, as the
1266 * intent of the caller is unknown here.
1267 */
1268 key_ref = lookup_user_key(serial, flags, KEY_DEFER_PERM_CHECK);
1269 if (IS_ERR(key_ref))
1270 return NULL;
1271
1272 bkey = kmalloc(sizeof(*bkey), GFP_KERNEL);
1273 if (!bkey) {
1274 key_put(key_ref_to_ptr(key_ref));
1275 return NULL;
1276 }
1277
1278 bkey->key = key_ref_to_ptr(key_ref);
1279 bkey->has_ref = true;
1280
1281 return bkey;
1282 }
1283
1284 /**
1285 * bpf_lookup_system_key - lookup a key by a system-defined ID
1286 * @id: key ID
1287 *
1288 * Obtain a bpf_key structure with a key pointer set to the passed key ID.
1289 * The key pointer is marked as invalid, to prevent bpf_key_put() from
1290 * attempting to decrement the key reference count on that pointer. The key
1291 * pointer set in such way is currently understood only by
1292 * verify_pkcs7_signature().
1293 *
1294 * Set *id* to one of the values defined in include/linux/verification.h:
1295 * 0 for the primary keyring (immutable keyring of system keys);
1296 * VERIFY_USE_SECONDARY_KEYRING for both the primary and secondary keyring
1297 * (where keys can be added only if they are vouched for by existing keys
1298 * in those keyrings); VERIFY_USE_PLATFORM_KEYRING for the platform
1299 * keyring (primarily used by the integrity subsystem to verify a kexec'ed
1300 * kerned image and, possibly, the initramfs signature).
1301 *
1302 * Return: a bpf_key pointer with an invalid key pointer set from the
1303 * pre-determined ID on success, a NULL pointer otherwise
1304 */
bpf_lookup_system_key(u64 id)1305 struct bpf_key *bpf_lookup_system_key(u64 id)
1306 {
1307 struct bpf_key *bkey;
1308
1309 if (system_keyring_id_check(id) < 0)
1310 return NULL;
1311
1312 bkey = kmalloc(sizeof(*bkey), GFP_ATOMIC);
1313 if (!bkey)
1314 return NULL;
1315
1316 bkey->key = (struct key *)(unsigned long)id;
1317 bkey->has_ref = false;
1318
1319 return bkey;
1320 }
1321
1322 /**
1323 * bpf_key_put - decrement key reference count if key is valid and free bpf_key
1324 * @bkey: bpf_key structure
1325 *
1326 * Decrement the reference count of the key inside *bkey*, if the pointer
1327 * is valid, and free *bkey*.
1328 */
bpf_key_put(struct bpf_key * bkey)1329 void bpf_key_put(struct bpf_key *bkey)
1330 {
1331 if (bkey->has_ref)
1332 key_put(bkey->key);
1333
1334 kfree(bkey);
1335 }
1336
1337 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1338 /**
1339 * bpf_verify_pkcs7_signature - verify a PKCS#7 signature
1340 * @data_ptr: data to verify
1341 * @sig_ptr: signature of the data
1342 * @trusted_keyring: keyring with keys trusted for signature verification
1343 *
1344 * Verify the PKCS#7 signature *sig_ptr* against the supplied *data_ptr*
1345 * with keys in a keyring referenced by *trusted_keyring*.
1346 *
1347 * Return: 0 on success, a negative value on error.
1348 */
bpf_verify_pkcs7_signature(struct bpf_dynptr_kern * data_ptr,struct bpf_dynptr_kern * sig_ptr,struct bpf_key * trusted_keyring)1349 int bpf_verify_pkcs7_signature(struct bpf_dynptr_kern *data_ptr,
1350 struct bpf_dynptr_kern *sig_ptr,
1351 struct bpf_key *trusted_keyring)
1352 {
1353 int ret;
1354
1355 if (trusted_keyring->has_ref) {
1356 /*
1357 * Do the permission check deferred in bpf_lookup_user_key().
1358 * See bpf_lookup_user_key() for more details.
1359 *
1360 * A call to key_task_permission() here would be redundant, as
1361 * it is already done by keyring_search() called by
1362 * find_asymmetric_key().
1363 */
1364 ret = key_validate(trusted_keyring->key);
1365 if (ret < 0)
1366 return ret;
1367 }
1368
1369 return verify_pkcs7_signature(data_ptr->data,
1370 bpf_dynptr_get_size(data_ptr),
1371 sig_ptr->data,
1372 bpf_dynptr_get_size(sig_ptr),
1373 trusted_keyring->key,
1374 VERIFYING_UNSPECIFIED_SIGNATURE, NULL,
1375 NULL);
1376 }
1377 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
1378
1379 __diag_pop();
1380
1381 BTF_SET8_START(key_sig_kfunc_set)
1382 BTF_ID_FLAGS(func, bpf_lookup_user_key, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE)
1383 BTF_ID_FLAGS(func, bpf_lookup_system_key, KF_ACQUIRE | KF_RET_NULL)
1384 BTF_ID_FLAGS(func, bpf_key_put, KF_RELEASE)
1385 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1386 BTF_ID_FLAGS(func, bpf_verify_pkcs7_signature, KF_SLEEPABLE)
1387 #endif
1388 BTF_SET8_END(key_sig_kfunc_set)
1389
1390 static const struct btf_kfunc_id_set bpf_key_sig_kfunc_set = {
1391 .owner = THIS_MODULE,
1392 .set = &key_sig_kfunc_set,
1393 };
1394
bpf_key_sig_kfuncs_init(void)1395 static int __init bpf_key_sig_kfuncs_init(void)
1396 {
1397 return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING,
1398 &bpf_key_sig_kfunc_set);
1399 }
1400
1401 late_initcall(bpf_key_sig_kfuncs_init);
1402 #endif /* CONFIG_KEYS */
1403
1404 static const struct bpf_func_proto *
bpf_tracing_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1405 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1406 {
1407 switch (func_id) {
1408 case BPF_FUNC_map_lookup_elem:
1409 return &bpf_map_lookup_elem_proto;
1410 case BPF_FUNC_map_update_elem:
1411 return &bpf_map_update_elem_proto;
1412 case BPF_FUNC_map_delete_elem:
1413 return &bpf_map_delete_elem_proto;
1414 case BPF_FUNC_map_push_elem:
1415 return &bpf_map_push_elem_proto;
1416 case BPF_FUNC_map_pop_elem:
1417 return &bpf_map_pop_elem_proto;
1418 case BPF_FUNC_map_peek_elem:
1419 return &bpf_map_peek_elem_proto;
1420 case BPF_FUNC_map_lookup_percpu_elem:
1421 return &bpf_map_lookup_percpu_elem_proto;
1422 case BPF_FUNC_ktime_get_ns:
1423 return &bpf_ktime_get_ns_proto;
1424 case BPF_FUNC_ktime_get_boot_ns:
1425 return &bpf_ktime_get_boot_ns_proto;
1426 case BPF_FUNC_tail_call:
1427 return &bpf_tail_call_proto;
1428 case BPF_FUNC_get_current_pid_tgid:
1429 return &bpf_get_current_pid_tgid_proto;
1430 case BPF_FUNC_get_current_task:
1431 return &bpf_get_current_task_proto;
1432 case BPF_FUNC_get_current_task_btf:
1433 return &bpf_get_current_task_btf_proto;
1434 case BPF_FUNC_task_pt_regs:
1435 return &bpf_task_pt_regs_proto;
1436 case BPF_FUNC_get_current_uid_gid:
1437 return &bpf_get_current_uid_gid_proto;
1438 case BPF_FUNC_get_current_comm:
1439 return &bpf_get_current_comm_proto;
1440 case BPF_FUNC_trace_printk:
1441 return bpf_get_trace_printk_proto();
1442 case BPF_FUNC_get_smp_processor_id:
1443 return &bpf_get_smp_processor_id_proto;
1444 case BPF_FUNC_get_numa_node_id:
1445 return &bpf_get_numa_node_id_proto;
1446 case BPF_FUNC_perf_event_read:
1447 return &bpf_perf_event_read_proto;
1448 case BPF_FUNC_current_task_under_cgroup:
1449 return &bpf_current_task_under_cgroup_proto;
1450 case BPF_FUNC_get_prandom_u32:
1451 return &bpf_get_prandom_u32_proto;
1452 case BPF_FUNC_probe_write_user:
1453 return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
1454 NULL : bpf_get_probe_write_proto();
1455 case BPF_FUNC_probe_read_user:
1456 return &bpf_probe_read_user_proto;
1457 case BPF_FUNC_probe_read_kernel:
1458 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1459 NULL : &bpf_probe_read_kernel_proto;
1460 case BPF_FUNC_probe_read_user_str:
1461 return &bpf_probe_read_user_str_proto;
1462 case BPF_FUNC_probe_read_kernel_str:
1463 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1464 NULL : &bpf_probe_read_kernel_str_proto;
1465 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1466 case BPF_FUNC_probe_read:
1467 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1468 NULL : &bpf_probe_read_compat_proto;
1469 case BPF_FUNC_probe_read_str:
1470 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1471 NULL : &bpf_probe_read_compat_str_proto;
1472 #endif
1473 #ifdef CONFIG_CGROUPS
1474 case BPF_FUNC_get_current_cgroup_id:
1475 return &bpf_get_current_cgroup_id_proto;
1476 case BPF_FUNC_get_current_ancestor_cgroup_id:
1477 return &bpf_get_current_ancestor_cgroup_id_proto;
1478 #endif
1479 case BPF_FUNC_send_signal:
1480 return &bpf_send_signal_proto;
1481 case BPF_FUNC_send_signal_thread:
1482 return &bpf_send_signal_thread_proto;
1483 case BPF_FUNC_perf_event_read_value:
1484 return &bpf_perf_event_read_value_proto;
1485 case BPF_FUNC_get_ns_current_pid_tgid:
1486 return &bpf_get_ns_current_pid_tgid_proto;
1487 case BPF_FUNC_ringbuf_output:
1488 return &bpf_ringbuf_output_proto;
1489 case BPF_FUNC_ringbuf_reserve:
1490 return &bpf_ringbuf_reserve_proto;
1491 case BPF_FUNC_ringbuf_submit:
1492 return &bpf_ringbuf_submit_proto;
1493 case BPF_FUNC_ringbuf_discard:
1494 return &bpf_ringbuf_discard_proto;
1495 case BPF_FUNC_ringbuf_query:
1496 return &bpf_ringbuf_query_proto;
1497 case BPF_FUNC_jiffies64:
1498 return &bpf_jiffies64_proto;
1499 case BPF_FUNC_get_task_stack:
1500 return &bpf_get_task_stack_proto;
1501 case BPF_FUNC_copy_from_user:
1502 return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
1503 case BPF_FUNC_copy_from_user_task:
1504 return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL;
1505 case BPF_FUNC_snprintf_btf:
1506 return &bpf_snprintf_btf_proto;
1507 case BPF_FUNC_per_cpu_ptr:
1508 return &bpf_per_cpu_ptr_proto;
1509 case BPF_FUNC_this_cpu_ptr:
1510 return &bpf_this_cpu_ptr_proto;
1511 case BPF_FUNC_task_storage_get:
1512 return &bpf_task_storage_get_proto;
1513 case BPF_FUNC_task_storage_delete:
1514 return &bpf_task_storage_delete_proto;
1515 case BPF_FUNC_for_each_map_elem:
1516 return &bpf_for_each_map_elem_proto;
1517 case BPF_FUNC_snprintf:
1518 return &bpf_snprintf_proto;
1519 case BPF_FUNC_get_func_ip:
1520 return &bpf_get_func_ip_proto_tracing;
1521 case BPF_FUNC_get_branch_snapshot:
1522 return &bpf_get_branch_snapshot_proto;
1523 case BPF_FUNC_find_vma:
1524 return &bpf_find_vma_proto;
1525 case BPF_FUNC_trace_vprintk:
1526 return bpf_get_trace_vprintk_proto();
1527 default:
1528 return bpf_base_func_proto(func_id);
1529 }
1530 }
1531
1532 static const struct bpf_func_proto *
kprobe_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1533 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1534 {
1535 switch (func_id) {
1536 case BPF_FUNC_perf_event_output:
1537 return &bpf_perf_event_output_proto;
1538 case BPF_FUNC_get_stackid:
1539 return &bpf_get_stackid_proto;
1540 case BPF_FUNC_get_stack:
1541 return &bpf_get_stack_proto;
1542 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1543 case BPF_FUNC_override_return:
1544 return &bpf_override_return_proto;
1545 #endif
1546 case BPF_FUNC_get_func_ip:
1547 return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
1548 &bpf_get_func_ip_proto_kprobe_multi :
1549 &bpf_get_func_ip_proto_kprobe;
1550 case BPF_FUNC_get_attach_cookie:
1551 return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
1552 &bpf_get_attach_cookie_proto_kmulti :
1553 &bpf_get_attach_cookie_proto_trace;
1554 default:
1555 return bpf_tracing_func_proto(func_id, prog);
1556 }
1557 }
1558
1559 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
kprobe_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1560 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1561 const struct bpf_prog *prog,
1562 struct bpf_insn_access_aux *info)
1563 {
1564 if (off < 0 || off >= sizeof(struct pt_regs))
1565 return false;
1566 if (type != BPF_READ)
1567 return false;
1568 if (off % size != 0)
1569 return false;
1570 /*
1571 * Assertion for 32 bit to make sure last 8 byte access
1572 * (BPF_DW) to the last 4 byte member is disallowed.
1573 */
1574 if (off + size > sizeof(struct pt_regs))
1575 return false;
1576
1577 return true;
1578 }
1579
1580 const struct bpf_verifier_ops kprobe_verifier_ops = {
1581 .get_func_proto = kprobe_prog_func_proto,
1582 .is_valid_access = kprobe_prog_is_valid_access,
1583 };
1584
1585 const struct bpf_prog_ops kprobe_prog_ops = {
1586 };
1587
BPF_CALL_5(bpf_perf_event_output_tp,void *,tp_buff,struct bpf_map *,map,u64,flags,void *,data,u64,size)1588 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1589 u64, flags, void *, data, u64, size)
1590 {
1591 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1592
1593 /*
1594 * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1595 * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1596 * from there and call the same bpf_perf_event_output() helper inline.
1597 */
1598 return ____bpf_perf_event_output(regs, map, flags, data, size);
1599 }
1600
1601 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1602 .func = bpf_perf_event_output_tp,
1603 .gpl_only = true,
1604 .ret_type = RET_INTEGER,
1605 .arg1_type = ARG_PTR_TO_CTX,
1606 .arg2_type = ARG_CONST_MAP_PTR,
1607 .arg3_type = ARG_ANYTHING,
1608 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1609 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1610 };
1611
BPF_CALL_3(bpf_get_stackid_tp,void *,tp_buff,struct bpf_map *,map,u64,flags)1612 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1613 u64, flags)
1614 {
1615 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1616
1617 /*
1618 * Same comment as in bpf_perf_event_output_tp(), only that this time
1619 * the other helper's function body cannot be inlined due to being
1620 * external, thus we need to call raw helper function.
1621 */
1622 return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1623 flags, 0, 0);
1624 }
1625
1626 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1627 .func = bpf_get_stackid_tp,
1628 .gpl_only = true,
1629 .ret_type = RET_INTEGER,
1630 .arg1_type = ARG_PTR_TO_CTX,
1631 .arg2_type = ARG_CONST_MAP_PTR,
1632 .arg3_type = ARG_ANYTHING,
1633 };
1634
BPF_CALL_4(bpf_get_stack_tp,void *,tp_buff,void *,buf,u32,size,u64,flags)1635 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1636 u64, flags)
1637 {
1638 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1639
1640 return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1641 (unsigned long) size, flags, 0);
1642 }
1643
1644 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1645 .func = bpf_get_stack_tp,
1646 .gpl_only = true,
1647 .ret_type = RET_INTEGER,
1648 .arg1_type = ARG_PTR_TO_CTX,
1649 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1650 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1651 .arg4_type = ARG_ANYTHING,
1652 };
1653
1654 static const struct bpf_func_proto *
tp_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1655 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1656 {
1657 switch (func_id) {
1658 case BPF_FUNC_perf_event_output:
1659 return &bpf_perf_event_output_proto_tp;
1660 case BPF_FUNC_get_stackid:
1661 return &bpf_get_stackid_proto_tp;
1662 case BPF_FUNC_get_stack:
1663 return &bpf_get_stack_proto_tp;
1664 case BPF_FUNC_get_attach_cookie:
1665 return &bpf_get_attach_cookie_proto_trace;
1666 default:
1667 return bpf_tracing_func_proto(func_id, prog);
1668 }
1669 }
1670
tp_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1671 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1672 const struct bpf_prog *prog,
1673 struct bpf_insn_access_aux *info)
1674 {
1675 if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1676 return false;
1677 if (type != BPF_READ)
1678 return false;
1679 if (off % size != 0)
1680 return false;
1681
1682 BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1683 return true;
1684 }
1685
1686 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1687 .get_func_proto = tp_prog_func_proto,
1688 .is_valid_access = tp_prog_is_valid_access,
1689 };
1690
1691 const struct bpf_prog_ops tracepoint_prog_ops = {
1692 };
1693
BPF_CALL_3(bpf_perf_prog_read_value,struct bpf_perf_event_data_kern *,ctx,struct bpf_perf_event_value *,buf,u32,size)1694 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1695 struct bpf_perf_event_value *, buf, u32, size)
1696 {
1697 int err = -EINVAL;
1698
1699 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1700 goto clear;
1701 err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1702 &buf->running);
1703 if (unlikely(err))
1704 goto clear;
1705 return 0;
1706 clear:
1707 memset(buf, 0, size);
1708 return err;
1709 }
1710
1711 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1712 .func = bpf_perf_prog_read_value,
1713 .gpl_only = true,
1714 .ret_type = RET_INTEGER,
1715 .arg1_type = ARG_PTR_TO_CTX,
1716 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1717 .arg3_type = ARG_CONST_SIZE,
1718 };
1719
BPF_CALL_4(bpf_read_branch_records,struct bpf_perf_event_data_kern *,ctx,void *,buf,u32,size,u64,flags)1720 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1721 void *, buf, u32, size, u64, flags)
1722 {
1723 static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1724 struct perf_branch_stack *br_stack = ctx->data->br_stack;
1725 u32 to_copy;
1726
1727 if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1728 return -EINVAL;
1729
1730 if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
1731 return -ENOENT;
1732
1733 if (unlikely(!br_stack))
1734 return -ENOENT;
1735
1736 if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1737 return br_stack->nr * br_entry_size;
1738
1739 if (!buf || (size % br_entry_size != 0))
1740 return -EINVAL;
1741
1742 to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1743 memcpy(buf, br_stack->entries, to_copy);
1744
1745 return to_copy;
1746 }
1747
1748 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1749 .func = bpf_read_branch_records,
1750 .gpl_only = true,
1751 .ret_type = RET_INTEGER,
1752 .arg1_type = ARG_PTR_TO_CTX,
1753 .arg2_type = ARG_PTR_TO_MEM_OR_NULL,
1754 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1755 .arg4_type = ARG_ANYTHING,
1756 };
1757
1758 static const struct bpf_func_proto *
pe_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1759 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1760 {
1761 switch (func_id) {
1762 case BPF_FUNC_perf_event_output:
1763 return &bpf_perf_event_output_proto_tp;
1764 case BPF_FUNC_get_stackid:
1765 return &bpf_get_stackid_proto_pe;
1766 case BPF_FUNC_get_stack:
1767 return &bpf_get_stack_proto_pe;
1768 case BPF_FUNC_perf_prog_read_value:
1769 return &bpf_perf_prog_read_value_proto;
1770 case BPF_FUNC_read_branch_records:
1771 return &bpf_read_branch_records_proto;
1772 case BPF_FUNC_get_attach_cookie:
1773 return &bpf_get_attach_cookie_proto_pe;
1774 default:
1775 return bpf_tracing_func_proto(func_id, prog);
1776 }
1777 }
1778
1779 /*
1780 * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1781 * to avoid potential recursive reuse issue when/if tracepoints are added
1782 * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1783 *
1784 * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1785 * in normal, irq, and nmi context.
1786 */
1787 struct bpf_raw_tp_regs {
1788 struct pt_regs regs[3];
1789 };
1790 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1791 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
get_bpf_raw_tp_regs(void)1792 static struct pt_regs *get_bpf_raw_tp_regs(void)
1793 {
1794 struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1795 int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1796
1797 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1798 this_cpu_dec(bpf_raw_tp_nest_level);
1799 return ERR_PTR(-EBUSY);
1800 }
1801
1802 return &tp_regs->regs[nest_level - 1];
1803 }
1804
put_bpf_raw_tp_regs(void)1805 static void put_bpf_raw_tp_regs(void)
1806 {
1807 this_cpu_dec(bpf_raw_tp_nest_level);
1808 }
1809
BPF_CALL_5(bpf_perf_event_output_raw_tp,struct bpf_raw_tracepoint_args *,args,struct bpf_map *,map,u64,flags,void *,data,u64,size)1810 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1811 struct bpf_map *, map, u64, flags, void *, data, u64, size)
1812 {
1813 struct pt_regs *regs = get_bpf_raw_tp_regs();
1814 int ret;
1815
1816 if (IS_ERR(regs))
1817 return PTR_ERR(regs);
1818
1819 perf_fetch_caller_regs(regs);
1820 ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1821
1822 put_bpf_raw_tp_regs();
1823 return ret;
1824 }
1825
1826 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1827 .func = bpf_perf_event_output_raw_tp,
1828 .gpl_only = true,
1829 .ret_type = RET_INTEGER,
1830 .arg1_type = ARG_PTR_TO_CTX,
1831 .arg2_type = ARG_CONST_MAP_PTR,
1832 .arg3_type = ARG_ANYTHING,
1833 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1834 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1835 };
1836
1837 extern const struct bpf_func_proto bpf_skb_output_proto;
1838 extern const struct bpf_func_proto bpf_xdp_output_proto;
1839 extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
1840
BPF_CALL_3(bpf_get_stackid_raw_tp,struct bpf_raw_tracepoint_args *,args,struct bpf_map *,map,u64,flags)1841 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1842 struct bpf_map *, map, u64, flags)
1843 {
1844 struct pt_regs *regs = get_bpf_raw_tp_regs();
1845 int ret;
1846
1847 if (IS_ERR(regs))
1848 return PTR_ERR(regs);
1849
1850 perf_fetch_caller_regs(regs);
1851 /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1852 ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1853 flags, 0, 0);
1854 put_bpf_raw_tp_regs();
1855 return ret;
1856 }
1857
1858 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1859 .func = bpf_get_stackid_raw_tp,
1860 .gpl_only = true,
1861 .ret_type = RET_INTEGER,
1862 .arg1_type = ARG_PTR_TO_CTX,
1863 .arg2_type = ARG_CONST_MAP_PTR,
1864 .arg3_type = ARG_ANYTHING,
1865 };
1866
BPF_CALL_4(bpf_get_stack_raw_tp,struct bpf_raw_tracepoint_args *,args,void *,buf,u32,size,u64,flags)1867 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1868 void *, buf, u32, size, u64, flags)
1869 {
1870 struct pt_regs *regs = get_bpf_raw_tp_regs();
1871 int ret;
1872
1873 if (IS_ERR(regs))
1874 return PTR_ERR(regs);
1875
1876 perf_fetch_caller_regs(regs);
1877 ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1878 (unsigned long) size, flags, 0);
1879 put_bpf_raw_tp_regs();
1880 return ret;
1881 }
1882
1883 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1884 .func = bpf_get_stack_raw_tp,
1885 .gpl_only = true,
1886 .ret_type = RET_INTEGER,
1887 .arg1_type = ARG_PTR_TO_CTX,
1888 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1889 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1890 .arg4_type = ARG_ANYTHING,
1891 };
1892
1893 static const struct bpf_func_proto *
raw_tp_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1894 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1895 {
1896 switch (func_id) {
1897 case BPF_FUNC_perf_event_output:
1898 return &bpf_perf_event_output_proto_raw_tp;
1899 case BPF_FUNC_get_stackid:
1900 return &bpf_get_stackid_proto_raw_tp;
1901 case BPF_FUNC_get_stack:
1902 return &bpf_get_stack_proto_raw_tp;
1903 default:
1904 return bpf_tracing_func_proto(func_id, prog);
1905 }
1906 }
1907
1908 const struct bpf_func_proto *
tracing_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1909 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1910 {
1911 const struct bpf_func_proto *fn;
1912
1913 switch (func_id) {
1914 #ifdef CONFIG_NET
1915 case BPF_FUNC_skb_output:
1916 return &bpf_skb_output_proto;
1917 case BPF_FUNC_xdp_output:
1918 return &bpf_xdp_output_proto;
1919 case BPF_FUNC_skc_to_tcp6_sock:
1920 return &bpf_skc_to_tcp6_sock_proto;
1921 case BPF_FUNC_skc_to_tcp_sock:
1922 return &bpf_skc_to_tcp_sock_proto;
1923 case BPF_FUNC_skc_to_tcp_timewait_sock:
1924 return &bpf_skc_to_tcp_timewait_sock_proto;
1925 case BPF_FUNC_skc_to_tcp_request_sock:
1926 return &bpf_skc_to_tcp_request_sock_proto;
1927 case BPF_FUNC_skc_to_udp6_sock:
1928 return &bpf_skc_to_udp6_sock_proto;
1929 case BPF_FUNC_skc_to_unix_sock:
1930 return &bpf_skc_to_unix_sock_proto;
1931 case BPF_FUNC_skc_to_mptcp_sock:
1932 return &bpf_skc_to_mptcp_sock_proto;
1933 case BPF_FUNC_sk_storage_get:
1934 return &bpf_sk_storage_get_tracing_proto;
1935 case BPF_FUNC_sk_storage_delete:
1936 return &bpf_sk_storage_delete_tracing_proto;
1937 case BPF_FUNC_sock_from_file:
1938 return &bpf_sock_from_file_proto;
1939 case BPF_FUNC_get_socket_cookie:
1940 return &bpf_get_socket_ptr_cookie_proto;
1941 case BPF_FUNC_xdp_get_buff_len:
1942 return &bpf_xdp_get_buff_len_trace_proto;
1943 #endif
1944 case BPF_FUNC_seq_printf:
1945 return prog->expected_attach_type == BPF_TRACE_ITER ?
1946 &bpf_seq_printf_proto :
1947 NULL;
1948 case BPF_FUNC_seq_write:
1949 return prog->expected_attach_type == BPF_TRACE_ITER ?
1950 &bpf_seq_write_proto :
1951 NULL;
1952 case BPF_FUNC_seq_printf_btf:
1953 return prog->expected_attach_type == BPF_TRACE_ITER ?
1954 &bpf_seq_printf_btf_proto :
1955 NULL;
1956 case BPF_FUNC_d_path:
1957 return &bpf_d_path_proto;
1958 case BPF_FUNC_get_func_arg:
1959 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
1960 case BPF_FUNC_get_func_ret:
1961 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
1962 case BPF_FUNC_get_func_arg_cnt:
1963 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
1964 case BPF_FUNC_get_attach_cookie:
1965 return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL;
1966 default:
1967 fn = raw_tp_prog_func_proto(func_id, prog);
1968 if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
1969 fn = bpf_iter_get_func_proto(func_id, prog);
1970 return fn;
1971 }
1972 }
1973
raw_tp_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1974 static bool raw_tp_prog_is_valid_access(int off, int size,
1975 enum bpf_access_type type,
1976 const struct bpf_prog *prog,
1977 struct bpf_insn_access_aux *info)
1978 {
1979 return bpf_tracing_ctx_access(off, size, type);
1980 }
1981
tracing_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1982 static bool tracing_prog_is_valid_access(int off, int size,
1983 enum bpf_access_type type,
1984 const struct bpf_prog *prog,
1985 struct bpf_insn_access_aux *info)
1986 {
1987 return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
1988 }
1989
bpf_prog_test_run_tracing(struct bpf_prog * prog,const union bpf_attr * kattr,union bpf_attr __user * uattr)1990 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
1991 const union bpf_attr *kattr,
1992 union bpf_attr __user *uattr)
1993 {
1994 return -ENOTSUPP;
1995 }
1996
1997 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
1998 .get_func_proto = raw_tp_prog_func_proto,
1999 .is_valid_access = raw_tp_prog_is_valid_access,
2000 };
2001
2002 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
2003 #ifdef CONFIG_NET
2004 .test_run = bpf_prog_test_run_raw_tp,
2005 #endif
2006 };
2007
2008 const struct bpf_verifier_ops tracing_verifier_ops = {
2009 .get_func_proto = tracing_prog_func_proto,
2010 .is_valid_access = tracing_prog_is_valid_access,
2011 };
2012
2013 const struct bpf_prog_ops tracing_prog_ops = {
2014 .test_run = bpf_prog_test_run_tracing,
2015 };
2016
raw_tp_writable_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)2017 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
2018 enum bpf_access_type type,
2019 const struct bpf_prog *prog,
2020 struct bpf_insn_access_aux *info)
2021 {
2022 if (off == 0) {
2023 if (size != sizeof(u64) || type != BPF_READ)
2024 return false;
2025 info->reg_type = PTR_TO_TP_BUFFER;
2026 }
2027 return raw_tp_prog_is_valid_access(off, size, type, prog, info);
2028 }
2029
2030 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
2031 .get_func_proto = raw_tp_prog_func_proto,
2032 .is_valid_access = raw_tp_writable_prog_is_valid_access,
2033 };
2034
2035 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
2036 };
2037
pe_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)2038 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
2039 const struct bpf_prog *prog,
2040 struct bpf_insn_access_aux *info)
2041 {
2042 const int size_u64 = sizeof(u64);
2043
2044 if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
2045 return false;
2046 if (type != BPF_READ)
2047 return false;
2048 if (off % size != 0) {
2049 if (sizeof(unsigned long) != 4)
2050 return false;
2051 if (size != 8)
2052 return false;
2053 if (off % size != 4)
2054 return false;
2055 }
2056
2057 switch (off) {
2058 case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
2059 bpf_ctx_record_field_size(info, size_u64);
2060 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2061 return false;
2062 break;
2063 case bpf_ctx_range(struct bpf_perf_event_data, addr):
2064 bpf_ctx_record_field_size(info, size_u64);
2065 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2066 return false;
2067 break;
2068 default:
2069 if (size != sizeof(long))
2070 return false;
2071 }
2072
2073 return true;
2074 }
2075
pe_prog_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)2076 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
2077 const struct bpf_insn *si,
2078 struct bpf_insn *insn_buf,
2079 struct bpf_prog *prog, u32 *target_size)
2080 {
2081 struct bpf_insn *insn = insn_buf;
2082
2083 switch (si->off) {
2084 case offsetof(struct bpf_perf_event_data, sample_period):
2085 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2086 data), si->dst_reg, si->src_reg,
2087 offsetof(struct bpf_perf_event_data_kern, data));
2088 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2089 bpf_target_off(struct perf_sample_data, period, 8,
2090 target_size));
2091 break;
2092 case offsetof(struct bpf_perf_event_data, addr):
2093 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2094 data), si->dst_reg, si->src_reg,
2095 offsetof(struct bpf_perf_event_data_kern, data));
2096 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2097 bpf_target_off(struct perf_sample_data, addr, 8,
2098 target_size));
2099 break;
2100 default:
2101 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2102 regs), si->dst_reg, si->src_reg,
2103 offsetof(struct bpf_perf_event_data_kern, regs));
2104 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
2105 si->off);
2106 break;
2107 }
2108
2109 return insn - insn_buf;
2110 }
2111
2112 const struct bpf_verifier_ops perf_event_verifier_ops = {
2113 .get_func_proto = pe_prog_func_proto,
2114 .is_valid_access = pe_prog_is_valid_access,
2115 .convert_ctx_access = pe_prog_convert_ctx_access,
2116 };
2117
2118 const struct bpf_prog_ops perf_event_prog_ops = {
2119 };
2120
2121 static DEFINE_MUTEX(bpf_event_mutex);
2122
2123 #define BPF_TRACE_MAX_PROGS 64
2124
perf_event_attach_bpf_prog(struct perf_event * event,struct bpf_prog * prog,u64 bpf_cookie)2125 int perf_event_attach_bpf_prog(struct perf_event *event,
2126 struct bpf_prog *prog,
2127 u64 bpf_cookie)
2128 {
2129 struct bpf_prog_array *old_array;
2130 struct bpf_prog_array *new_array;
2131 int ret = -EEXIST;
2132
2133 /*
2134 * Kprobe override only works if they are on the function entry,
2135 * and only if they are on the opt-in list.
2136 */
2137 if (prog->kprobe_override &&
2138 (!trace_kprobe_on_func_entry(event->tp_event) ||
2139 !trace_kprobe_error_injectable(event->tp_event)))
2140 return -EINVAL;
2141
2142 mutex_lock(&bpf_event_mutex);
2143
2144 if (event->prog)
2145 goto unlock;
2146
2147 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2148 if (old_array &&
2149 bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
2150 ret = -E2BIG;
2151 goto unlock;
2152 }
2153
2154 ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
2155 if (ret < 0)
2156 goto unlock;
2157
2158 /* set the new array to event->tp_event and set event->prog */
2159 event->prog = prog;
2160 event->bpf_cookie = bpf_cookie;
2161 rcu_assign_pointer(event->tp_event->prog_array, new_array);
2162 bpf_prog_array_free_sleepable(old_array);
2163
2164 unlock:
2165 mutex_unlock(&bpf_event_mutex);
2166 return ret;
2167 }
2168
perf_event_detach_bpf_prog(struct perf_event * event)2169 void perf_event_detach_bpf_prog(struct perf_event *event)
2170 {
2171 struct bpf_prog_array *old_array;
2172 struct bpf_prog_array *new_array;
2173 int ret;
2174
2175 mutex_lock(&bpf_event_mutex);
2176
2177 if (!event->prog)
2178 goto unlock;
2179
2180 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2181 ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
2182 if (ret == -ENOENT)
2183 goto unlock;
2184 if (ret < 0) {
2185 bpf_prog_array_delete_safe(old_array, event->prog);
2186 } else {
2187 rcu_assign_pointer(event->tp_event->prog_array, new_array);
2188 bpf_prog_array_free_sleepable(old_array);
2189 }
2190
2191 bpf_prog_put(event->prog);
2192 event->prog = NULL;
2193
2194 unlock:
2195 mutex_unlock(&bpf_event_mutex);
2196 }
2197
perf_event_query_prog_array(struct perf_event * event,void __user * info)2198 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
2199 {
2200 struct perf_event_query_bpf __user *uquery = info;
2201 struct perf_event_query_bpf query = {};
2202 struct bpf_prog_array *progs;
2203 u32 *ids, prog_cnt, ids_len;
2204 int ret;
2205
2206 if (!perfmon_capable())
2207 return -EPERM;
2208 if (event->attr.type != PERF_TYPE_TRACEPOINT)
2209 return -EINVAL;
2210 if (copy_from_user(&query, uquery, sizeof(query)))
2211 return -EFAULT;
2212
2213 ids_len = query.ids_len;
2214 if (ids_len > BPF_TRACE_MAX_PROGS)
2215 return -E2BIG;
2216 ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
2217 if (!ids)
2218 return -ENOMEM;
2219 /*
2220 * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
2221 * is required when user only wants to check for uquery->prog_cnt.
2222 * There is no need to check for it since the case is handled
2223 * gracefully in bpf_prog_array_copy_info.
2224 */
2225
2226 mutex_lock(&bpf_event_mutex);
2227 progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
2228 ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
2229 mutex_unlock(&bpf_event_mutex);
2230
2231 if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
2232 copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
2233 ret = -EFAULT;
2234
2235 kfree(ids);
2236 return ret;
2237 }
2238
2239 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
2240 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
2241
bpf_get_raw_tracepoint(const char * name)2242 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
2243 {
2244 struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
2245
2246 for (; btp < __stop__bpf_raw_tp; btp++) {
2247 if (!strcmp(btp->tp->name, name))
2248 return btp;
2249 }
2250
2251 return bpf_get_raw_tracepoint_module(name);
2252 }
2253
bpf_put_raw_tracepoint(struct bpf_raw_event_map * btp)2254 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
2255 {
2256 struct module *mod;
2257
2258 preempt_disable();
2259 mod = __module_address((unsigned long)btp);
2260 module_put(mod);
2261 preempt_enable();
2262 }
2263
2264 static __always_inline
__bpf_trace_run(struct bpf_prog * prog,u64 * args)2265 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
2266 {
2267 cant_sleep();
2268 if (unlikely(this_cpu_inc_return(*(prog->active)) != 1)) {
2269 bpf_prog_inc_misses_counter(prog);
2270 goto out;
2271 }
2272 rcu_read_lock();
2273 (void) bpf_prog_run(prog, args);
2274 rcu_read_unlock();
2275 out:
2276 this_cpu_dec(*(prog->active));
2277 }
2278
2279 #define UNPACK(...) __VA_ARGS__
2280 #define REPEAT_1(FN, DL, X, ...) FN(X)
2281 #define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
2282 #define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
2283 #define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
2284 #define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
2285 #define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
2286 #define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
2287 #define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
2288 #define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
2289 #define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
2290 #define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
2291 #define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
2292 #define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
2293
2294 #define SARG(X) u64 arg##X
2295 #define COPY(X) args[X] = arg##X
2296
2297 #define __DL_COM (,)
2298 #define __DL_SEM (;)
2299
2300 #define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
2301
2302 #define BPF_TRACE_DEFN_x(x) \
2303 void bpf_trace_run##x(struct bpf_prog *prog, \
2304 REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
2305 { \
2306 u64 args[x]; \
2307 REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
2308 __bpf_trace_run(prog, args); \
2309 } \
2310 EXPORT_SYMBOL_GPL(bpf_trace_run##x)
2311 BPF_TRACE_DEFN_x(1);
2312 BPF_TRACE_DEFN_x(2);
2313 BPF_TRACE_DEFN_x(3);
2314 BPF_TRACE_DEFN_x(4);
2315 BPF_TRACE_DEFN_x(5);
2316 BPF_TRACE_DEFN_x(6);
2317 BPF_TRACE_DEFN_x(7);
2318 BPF_TRACE_DEFN_x(8);
2319 BPF_TRACE_DEFN_x(9);
2320 BPF_TRACE_DEFN_x(10);
2321 BPF_TRACE_DEFN_x(11);
2322 BPF_TRACE_DEFN_x(12);
2323
__bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2324 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2325 {
2326 struct tracepoint *tp = btp->tp;
2327
2328 /*
2329 * check that program doesn't access arguments beyond what's
2330 * available in this tracepoint
2331 */
2332 if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
2333 return -EINVAL;
2334
2335 if (prog->aux->max_tp_access > btp->writable_size)
2336 return -EINVAL;
2337
2338 return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
2339 prog);
2340 }
2341
bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2342 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2343 {
2344 return __bpf_probe_register(btp, prog);
2345 }
2346
bpf_probe_unregister(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2347 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2348 {
2349 return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
2350 }
2351
bpf_get_perf_event_info(const struct perf_event * event,u32 * prog_id,u32 * fd_type,const char ** buf,u64 * probe_offset,u64 * probe_addr)2352 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
2353 u32 *fd_type, const char **buf,
2354 u64 *probe_offset, u64 *probe_addr)
2355 {
2356 bool is_tracepoint, is_syscall_tp;
2357 struct bpf_prog *prog;
2358 int flags, err = 0;
2359
2360 prog = event->prog;
2361 if (!prog)
2362 return -ENOENT;
2363
2364 /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
2365 if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
2366 return -EOPNOTSUPP;
2367
2368 *prog_id = prog->aux->id;
2369 flags = event->tp_event->flags;
2370 is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
2371 is_syscall_tp = is_syscall_trace_event(event->tp_event);
2372
2373 if (is_tracepoint || is_syscall_tp) {
2374 *buf = is_tracepoint ? event->tp_event->tp->name
2375 : event->tp_event->name;
2376 *fd_type = BPF_FD_TYPE_TRACEPOINT;
2377 *probe_offset = 0x0;
2378 *probe_addr = 0x0;
2379 } else {
2380 /* kprobe/uprobe */
2381 err = -EOPNOTSUPP;
2382 #ifdef CONFIG_KPROBE_EVENTS
2383 if (flags & TRACE_EVENT_FL_KPROBE)
2384 err = bpf_get_kprobe_info(event, fd_type, buf,
2385 probe_offset, probe_addr,
2386 event->attr.type == PERF_TYPE_TRACEPOINT);
2387 #endif
2388 #ifdef CONFIG_UPROBE_EVENTS
2389 if (flags & TRACE_EVENT_FL_UPROBE)
2390 err = bpf_get_uprobe_info(event, fd_type, buf,
2391 probe_offset, probe_addr,
2392 event->attr.type == PERF_TYPE_TRACEPOINT);
2393 #endif
2394 }
2395
2396 return err;
2397 }
2398
send_signal_irq_work_init(void)2399 static int __init send_signal_irq_work_init(void)
2400 {
2401 int cpu;
2402 struct send_signal_irq_work *work;
2403
2404 for_each_possible_cpu(cpu) {
2405 work = per_cpu_ptr(&send_signal_work, cpu);
2406 init_irq_work(&work->irq_work, do_bpf_send_signal);
2407 }
2408 return 0;
2409 }
2410
2411 subsys_initcall(send_signal_irq_work_init);
2412
2413 #ifdef CONFIG_MODULES
bpf_event_notify(struct notifier_block * nb,unsigned long op,void * module)2414 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
2415 void *module)
2416 {
2417 struct bpf_trace_module *btm, *tmp;
2418 struct module *mod = module;
2419 int ret = 0;
2420
2421 if (mod->num_bpf_raw_events == 0 ||
2422 (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
2423 goto out;
2424
2425 mutex_lock(&bpf_module_mutex);
2426
2427 switch (op) {
2428 case MODULE_STATE_COMING:
2429 btm = kzalloc(sizeof(*btm), GFP_KERNEL);
2430 if (btm) {
2431 btm->module = module;
2432 list_add(&btm->list, &bpf_trace_modules);
2433 } else {
2434 ret = -ENOMEM;
2435 }
2436 break;
2437 case MODULE_STATE_GOING:
2438 list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
2439 if (btm->module == module) {
2440 list_del(&btm->list);
2441 kfree(btm);
2442 break;
2443 }
2444 }
2445 break;
2446 }
2447
2448 mutex_unlock(&bpf_module_mutex);
2449
2450 out:
2451 return notifier_from_errno(ret);
2452 }
2453
2454 static struct notifier_block bpf_module_nb = {
2455 .notifier_call = bpf_event_notify,
2456 };
2457
bpf_event_init(void)2458 static int __init bpf_event_init(void)
2459 {
2460 register_module_notifier(&bpf_module_nb);
2461 return 0;
2462 }
2463
2464 fs_initcall(bpf_event_init);
2465 #endif /* CONFIG_MODULES */
2466
2467 #ifdef CONFIG_FPROBE
2468 struct bpf_kprobe_multi_link {
2469 struct bpf_link link;
2470 struct fprobe fp;
2471 unsigned long *addrs;
2472 u64 *cookies;
2473 u32 cnt;
2474 };
2475
2476 struct bpf_kprobe_multi_run_ctx {
2477 struct bpf_run_ctx run_ctx;
2478 struct bpf_kprobe_multi_link *link;
2479 unsigned long entry_ip;
2480 };
2481
2482 struct user_syms {
2483 const char **syms;
2484 char *buf;
2485 };
2486
copy_user_syms(struct user_syms * us,unsigned long __user * usyms,u32 cnt)2487 static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
2488 {
2489 unsigned long __user usymbol;
2490 const char **syms = NULL;
2491 char *buf = NULL, *p;
2492 int err = -ENOMEM;
2493 unsigned int i;
2494
2495 syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
2496 if (!syms)
2497 goto error;
2498
2499 buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
2500 if (!buf)
2501 goto error;
2502
2503 for (p = buf, i = 0; i < cnt; i++) {
2504 if (__get_user(usymbol, usyms + i)) {
2505 err = -EFAULT;
2506 goto error;
2507 }
2508 err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN);
2509 if (err == KSYM_NAME_LEN)
2510 err = -E2BIG;
2511 if (err < 0)
2512 goto error;
2513 syms[i] = p;
2514 p += err + 1;
2515 }
2516
2517 us->syms = syms;
2518 us->buf = buf;
2519 return 0;
2520
2521 error:
2522 if (err) {
2523 kvfree(syms);
2524 kvfree(buf);
2525 }
2526 return err;
2527 }
2528
free_user_syms(struct user_syms * us)2529 static void free_user_syms(struct user_syms *us)
2530 {
2531 kvfree(us->syms);
2532 kvfree(us->buf);
2533 }
2534
bpf_kprobe_multi_link_release(struct bpf_link * link)2535 static void bpf_kprobe_multi_link_release(struct bpf_link *link)
2536 {
2537 struct bpf_kprobe_multi_link *kmulti_link;
2538
2539 kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2540 unregister_fprobe(&kmulti_link->fp);
2541 }
2542
bpf_kprobe_multi_link_dealloc(struct bpf_link * link)2543 static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
2544 {
2545 struct bpf_kprobe_multi_link *kmulti_link;
2546
2547 kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2548 kvfree(kmulti_link->addrs);
2549 kvfree(kmulti_link->cookies);
2550 kfree(kmulti_link);
2551 }
2552
2553 static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
2554 .release = bpf_kprobe_multi_link_release,
2555 .dealloc = bpf_kprobe_multi_link_dealloc,
2556 };
2557
bpf_kprobe_multi_cookie_swap(void * a,void * b,int size,const void * priv)2558 static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
2559 {
2560 const struct bpf_kprobe_multi_link *link = priv;
2561 unsigned long *addr_a = a, *addr_b = b;
2562 u64 *cookie_a, *cookie_b;
2563
2564 cookie_a = link->cookies + (addr_a - link->addrs);
2565 cookie_b = link->cookies + (addr_b - link->addrs);
2566
2567 /* swap addr_a/addr_b and cookie_a/cookie_b values */
2568 swap(*addr_a, *addr_b);
2569 swap(*cookie_a, *cookie_b);
2570 }
2571
__bpf_kprobe_multi_cookie_cmp(const void * a,const void * b)2572 static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b)
2573 {
2574 const unsigned long *addr_a = a, *addr_b = b;
2575
2576 if (*addr_a == *addr_b)
2577 return 0;
2578 return *addr_a < *addr_b ? -1 : 1;
2579 }
2580
bpf_kprobe_multi_cookie_cmp(const void * a,const void * b,const void * priv)2581 static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
2582 {
2583 return __bpf_kprobe_multi_cookie_cmp(a, b);
2584 }
2585
bpf_kprobe_multi_cookie(struct bpf_run_ctx * ctx)2586 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2587 {
2588 struct bpf_kprobe_multi_run_ctx *run_ctx;
2589 struct bpf_kprobe_multi_link *link;
2590 u64 *cookie, entry_ip;
2591 unsigned long *addr;
2592
2593 if (WARN_ON_ONCE(!ctx))
2594 return 0;
2595 run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2596 link = run_ctx->link;
2597 if (!link->cookies)
2598 return 0;
2599 entry_ip = run_ctx->entry_ip;
2600 addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
2601 __bpf_kprobe_multi_cookie_cmp);
2602 if (!addr)
2603 return 0;
2604 cookie = link->cookies + (addr - link->addrs);
2605 return *cookie;
2606 }
2607
bpf_kprobe_multi_entry_ip(struct bpf_run_ctx * ctx)2608 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2609 {
2610 struct bpf_kprobe_multi_run_ctx *run_ctx;
2611
2612 run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2613 return run_ctx->entry_ip;
2614 }
2615
2616 static int
kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link * link,unsigned long entry_ip,struct pt_regs * regs)2617 kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
2618 unsigned long entry_ip, struct pt_regs *regs)
2619 {
2620 struct bpf_kprobe_multi_run_ctx run_ctx = {
2621 .link = link,
2622 .entry_ip = entry_ip,
2623 };
2624 struct bpf_run_ctx *old_run_ctx;
2625 int err;
2626
2627 if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
2628 err = 0;
2629 goto out;
2630 }
2631
2632 migrate_disable();
2633 rcu_read_lock();
2634 old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
2635 err = bpf_prog_run(link->link.prog, regs);
2636 bpf_reset_run_ctx(old_run_ctx);
2637 rcu_read_unlock();
2638 migrate_enable();
2639
2640 out:
2641 __this_cpu_dec(bpf_prog_active);
2642 return err;
2643 }
2644
2645 static void
kprobe_multi_link_handler(struct fprobe * fp,unsigned long fentry_ip,struct pt_regs * regs,void * data)2646 kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
2647 struct pt_regs *regs, void *data)
2648 {
2649 struct bpf_kprobe_multi_link *link;
2650
2651 link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2652 kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs);
2653 }
2654
symbols_cmp_r(const void * a,const void * b,const void * priv)2655 static int symbols_cmp_r(const void *a, const void *b, const void *priv)
2656 {
2657 const char **str_a = (const char **) a;
2658 const char **str_b = (const char **) b;
2659
2660 return strcmp(*str_a, *str_b);
2661 }
2662
2663 struct multi_symbols_sort {
2664 const char **funcs;
2665 u64 *cookies;
2666 };
2667
symbols_swap_r(void * a,void * b,int size,const void * priv)2668 static void symbols_swap_r(void *a, void *b, int size, const void *priv)
2669 {
2670 const struct multi_symbols_sort *data = priv;
2671 const char **name_a = a, **name_b = b;
2672
2673 swap(*name_a, *name_b);
2674
2675 /* If defined, swap also related cookies. */
2676 if (data->cookies) {
2677 u64 *cookie_a, *cookie_b;
2678
2679 cookie_a = data->cookies + (name_a - data->funcs);
2680 cookie_b = data->cookies + (name_b - data->funcs);
2681 swap(*cookie_a, *cookie_b);
2682 }
2683 }
2684
addrs_check_error_injection_list(unsigned long * addrs,u32 cnt)2685 static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt)
2686 {
2687 u32 i;
2688
2689 for (i = 0; i < cnt; i++) {
2690 if (!within_error_injection_list(addrs[i]))
2691 return -EINVAL;
2692 }
2693 return 0;
2694 }
2695
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)2696 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2697 {
2698 struct bpf_kprobe_multi_link *link = NULL;
2699 struct bpf_link_primer link_primer;
2700 void __user *ucookies;
2701 unsigned long *addrs;
2702 u32 flags, cnt, size;
2703 void __user *uaddrs;
2704 u64 *cookies = NULL;
2705 void __user *usyms;
2706 int err;
2707
2708 /* no support for 32bit archs yet */
2709 if (sizeof(u64) != sizeof(void *))
2710 return -EOPNOTSUPP;
2711
2712 if (prog->expected_attach_type != BPF_TRACE_KPROBE_MULTI)
2713 return -EINVAL;
2714
2715 flags = attr->link_create.kprobe_multi.flags;
2716 if (flags & ~BPF_F_KPROBE_MULTI_RETURN)
2717 return -EINVAL;
2718
2719 uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs);
2720 usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms);
2721 if (!!uaddrs == !!usyms)
2722 return -EINVAL;
2723
2724 cnt = attr->link_create.kprobe_multi.cnt;
2725 if (!cnt)
2726 return -EINVAL;
2727
2728 size = cnt * sizeof(*addrs);
2729 addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2730 if (!addrs)
2731 return -ENOMEM;
2732
2733 ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
2734 if (ucookies) {
2735 cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2736 if (!cookies) {
2737 err = -ENOMEM;
2738 goto error;
2739 }
2740 if (copy_from_user(cookies, ucookies, size)) {
2741 err = -EFAULT;
2742 goto error;
2743 }
2744 }
2745
2746 if (uaddrs) {
2747 if (copy_from_user(addrs, uaddrs, size)) {
2748 err = -EFAULT;
2749 goto error;
2750 }
2751 } else {
2752 struct multi_symbols_sort data = {
2753 .cookies = cookies,
2754 };
2755 struct user_syms us;
2756
2757 err = copy_user_syms(&us, usyms, cnt);
2758 if (err)
2759 goto error;
2760
2761 if (cookies)
2762 data.funcs = us.syms;
2763
2764 sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r,
2765 symbols_swap_r, &data);
2766
2767 err = ftrace_lookup_symbols(us.syms, cnt, addrs);
2768 free_user_syms(&us);
2769 if (err)
2770 goto error;
2771 }
2772
2773 if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) {
2774 err = -EINVAL;
2775 goto error;
2776 }
2777
2778 link = kzalloc(sizeof(*link), GFP_KERNEL);
2779 if (!link) {
2780 err = -ENOMEM;
2781 goto error;
2782 }
2783
2784 bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI,
2785 &bpf_kprobe_multi_link_lops, prog);
2786
2787 err = bpf_link_prime(&link->link, &link_primer);
2788 if (err)
2789 goto error;
2790
2791 if (flags & BPF_F_KPROBE_MULTI_RETURN)
2792 link->fp.exit_handler = kprobe_multi_link_handler;
2793 else
2794 link->fp.entry_handler = kprobe_multi_link_handler;
2795
2796 link->addrs = addrs;
2797 link->cookies = cookies;
2798 link->cnt = cnt;
2799
2800 if (cookies) {
2801 /*
2802 * Sorting addresses will trigger sorting cookies as well
2803 * (check bpf_kprobe_multi_cookie_swap). This way we can
2804 * find cookie based on the address in bpf_get_attach_cookie
2805 * helper.
2806 */
2807 sort_r(addrs, cnt, sizeof(*addrs),
2808 bpf_kprobe_multi_cookie_cmp,
2809 bpf_kprobe_multi_cookie_swap,
2810 link);
2811 }
2812
2813 err = register_fprobe_ips(&link->fp, addrs, cnt);
2814 if (err) {
2815 bpf_link_cleanup(&link_primer);
2816 return err;
2817 }
2818
2819 return bpf_link_settle(&link_primer);
2820
2821 error:
2822 kfree(link);
2823 kvfree(addrs);
2824 kvfree(cookies);
2825 return err;
2826 }
2827 #else /* !CONFIG_FPROBE */
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)2828 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2829 {
2830 return -EOPNOTSUPP;
2831 }
bpf_kprobe_multi_cookie(struct bpf_run_ctx * ctx)2832 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2833 {
2834 return 0;
2835 }
bpf_kprobe_multi_entry_ip(struct bpf_run_ctx * ctx)2836 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2837 {
2838 return 0;
2839 }
2840 #endif
2841