bpf: Extend bpf_base_func_proto helpers with probe_* and *current_task*
[linux-2.6-microblaze.git] / kernel / trace / bpf_trace.c
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/filter.h>
11 #include <linux/uaccess.h>
12 #include <linux/ctype.h>
13 #include <linux/kprobes.h>
14 #include <linux/syscalls.h>
15 #include <linux/error-injection.h>
16
17 #include <asm/tlb.h>
18
19 #include "trace_probe.h"
20 #include "trace.h"
21
22 #define bpf_event_rcu_dereference(p)                                    \
23         rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
24
25 #ifdef CONFIG_MODULES
26 struct bpf_trace_module {
27         struct module *module;
28         struct list_head list;
29 };
30
31 static LIST_HEAD(bpf_trace_modules);
32 static DEFINE_MUTEX(bpf_module_mutex);
33
34 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
35 {
36         struct bpf_raw_event_map *btp, *ret = NULL;
37         struct bpf_trace_module *btm;
38         unsigned int i;
39
40         mutex_lock(&bpf_module_mutex);
41         list_for_each_entry(btm, &bpf_trace_modules, list) {
42                 for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
43                         btp = &btm->module->bpf_raw_events[i];
44                         if (!strcmp(btp->tp->name, name)) {
45                                 if (try_module_get(btm->module))
46                                         ret = btp;
47                                 goto out;
48                         }
49                 }
50         }
51 out:
52         mutex_unlock(&bpf_module_mutex);
53         return ret;
54 }
55 #else
56 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
57 {
58         return NULL;
59 }
60 #endif /* CONFIG_MODULES */
61
62 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
63 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
64
65 /**
66  * trace_call_bpf - invoke BPF program
67  * @call: tracepoint event
68  * @ctx: opaque context pointer
69  *
70  * kprobe handlers execute BPF programs via this helper.
71  * Can be used from static tracepoints in the future.
72  *
73  * Return: BPF programs always return an integer which is interpreted by
74  * kprobe handler as:
75  * 0 - return from kprobe (event is filtered out)
76  * 1 - store kprobe event into ring buffer
77  * Other values are reserved and currently alias to 1
78  */
79 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
80 {
81         unsigned int ret;
82
83         if (in_nmi()) /* not supported yet */
84                 return 1;
85
86         cant_sleep();
87
88         if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
89                 /*
90                  * since some bpf program is already running on this cpu,
91                  * don't call into another bpf program (same or different)
92                  * and don't send kprobe event into ring-buffer,
93                  * so return zero here
94                  */
95                 ret = 0;
96                 goto out;
97         }
98
99         /*
100          * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
101          * to all call sites, we did a bpf_prog_array_valid() there to check
102          * whether call->prog_array is empty or not, which is
103          * a heurisitc to speed up execution.
104          *
105          * If bpf_prog_array_valid() fetched prog_array was
106          * non-NULL, we go into trace_call_bpf() and do the actual
107          * proper rcu_dereference() under RCU lock.
108          * If it turns out that prog_array is NULL then, we bail out.
109          * For the opposite, if the bpf_prog_array_valid() fetched pointer
110          * was NULL, you'll skip the prog_array with the risk of missing
111          * out of events when it was updated in between this and the
112          * rcu_dereference() which is accepted risk.
113          */
114         ret = BPF_PROG_RUN_ARRAY_CHECK(call->prog_array, ctx, BPF_PROG_RUN);
115
116  out:
117         __this_cpu_dec(bpf_prog_active);
118
119         return ret;
120 }
121
122 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
123 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
124 {
125         regs_set_return_value(regs, rc);
126         override_function_with_return(regs);
127         return 0;
128 }
129
130 static const struct bpf_func_proto bpf_override_return_proto = {
131         .func           = bpf_override_return,
132         .gpl_only       = true,
133         .ret_type       = RET_INTEGER,
134         .arg1_type      = ARG_PTR_TO_CTX,
135         .arg2_type      = ARG_ANYTHING,
136 };
137 #endif
138
139 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
140            const void __user *, unsafe_ptr)
141 {
142         int ret = probe_user_read(dst, unsafe_ptr, size);
143
144         if (unlikely(ret < 0))
145                 memset(dst, 0, size);
146
147         return ret;
148 }
149
150 const struct bpf_func_proto bpf_probe_read_user_proto = {
151         .func           = bpf_probe_read_user,
152         .gpl_only       = true,
153         .ret_type       = RET_INTEGER,
154         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
155         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
156         .arg3_type      = ARG_ANYTHING,
157 };
158
159 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
160            const void __user *, unsafe_ptr)
161 {
162         int ret = strncpy_from_unsafe_user(dst, unsafe_ptr, size);
163
164         if (unlikely(ret < 0))
165                 memset(dst, 0, size);
166
167         return ret;
168 }
169
170 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
171         .func           = bpf_probe_read_user_str,
172         .gpl_only       = true,
173         .ret_type       = RET_INTEGER,
174         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
175         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
176         .arg3_type      = ARG_ANYTHING,
177 };
178
179 static __always_inline int
180 bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr,
181                              const bool compat)
182 {
183         int ret = security_locked_down(LOCKDOWN_BPF_READ);
184
185         if (unlikely(ret < 0))
186                 goto out;
187         ret = compat ? probe_kernel_read(dst, unsafe_ptr, size) :
188               probe_kernel_read_strict(dst, unsafe_ptr, size);
189         if (unlikely(ret < 0))
190 out:
191                 memset(dst, 0, size);
192         return ret;
193 }
194
195 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
196            const void *, unsafe_ptr)
197 {
198         return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, false);
199 }
200
201 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
202         .func           = bpf_probe_read_kernel,
203         .gpl_only       = true,
204         .ret_type       = RET_INTEGER,
205         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
206         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
207         .arg3_type      = ARG_ANYTHING,
208 };
209
210 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
211            const void *, unsafe_ptr)
212 {
213         return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, true);
214 }
215
216 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
217         .func           = bpf_probe_read_compat,
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
226 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr,
227                                  const bool compat)
228 {
229         int ret = security_locked_down(LOCKDOWN_BPF_READ);
230
231         if (unlikely(ret < 0))
232                 goto out;
233         /*
234          * The strncpy_from_unsafe_*() call will likely not fill the entire
235          * buffer, but that's okay in this circumstance as we're probing
236          * arbitrary memory anyway similar to bpf_probe_read_*() and might
237          * as well probe the stack. Thus, memory is explicitly cleared
238          * only in error case, so that improper users ignoring return
239          * code altogether don't copy garbage; otherwise length of string
240          * is returned that can be used for bpf_perf_event_output() et al.
241          */
242         ret = compat ? strncpy_from_unsafe(dst, unsafe_ptr, size) :
243               strncpy_from_unsafe_strict(dst, unsafe_ptr, size);
244         if (unlikely(ret < 0))
245 out:
246                 memset(dst, 0, size);
247         return ret;
248 }
249
250 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
251            const void *, unsafe_ptr)
252 {
253         return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, false);
254 }
255
256 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
257         .func           = bpf_probe_read_kernel_str,
258         .gpl_only       = true,
259         .ret_type       = RET_INTEGER,
260         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
261         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
262         .arg3_type      = ARG_ANYTHING,
263 };
264
265 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
266            const void *, unsafe_ptr)
267 {
268         return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, true);
269 }
270
271 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
272         .func           = bpf_probe_read_compat_str,
273         .gpl_only       = true,
274         .ret_type       = RET_INTEGER,
275         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
276         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
277         .arg3_type      = ARG_ANYTHING,
278 };
279
280 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
281            u32, size)
282 {
283         /*
284          * Ensure we're in user context which is safe for the helper to
285          * run. This helper has no business in a kthread.
286          *
287          * access_ok() should prevent writing to non-user memory, but in
288          * some situations (nommu, temporary switch, etc) access_ok() does
289          * not provide enough validation, hence the check on KERNEL_DS.
290          *
291          * nmi_uaccess_okay() ensures the probe is not run in an interim
292          * state, when the task or mm are switched. This is specifically
293          * required to prevent the use of temporary mm.
294          */
295
296         if (unlikely(in_interrupt() ||
297                      current->flags & (PF_KTHREAD | PF_EXITING)))
298                 return -EPERM;
299         if (unlikely(uaccess_kernel()))
300                 return -EPERM;
301         if (unlikely(!nmi_uaccess_okay()))
302                 return -EPERM;
303
304         return probe_user_write(unsafe_ptr, src, size);
305 }
306
307 static const struct bpf_func_proto bpf_probe_write_user_proto = {
308         .func           = bpf_probe_write_user,
309         .gpl_only       = true,
310         .ret_type       = RET_INTEGER,
311         .arg1_type      = ARG_ANYTHING,
312         .arg2_type      = ARG_PTR_TO_MEM,
313         .arg3_type      = ARG_CONST_SIZE,
314 };
315
316 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
317 {
318         if (!capable(CAP_SYS_ADMIN))
319                 return NULL;
320
321         pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
322                             current->comm, task_pid_nr(current));
323
324         return &bpf_probe_write_user_proto;
325 }
326
327 /*
328  * Only limited trace_printk() conversion specifiers allowed:
329  * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s
330  */
331 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
332            u64, arg2, u64, arg3)
333 {
334         int i, mod[3] = {}, fmt_cnt = 0;
335         char buf[64], fmt_ptype;
336         void *unsafe_ptr = NULL;
337         bool str_seen = false;
338
339         /*
340          * bpf_check()->check_func_arg()->check_stack_boundary()
341          * guarantees that fmt points to bpf program stack,
342          * fmt_size bytes of it were initialized and fmt_size > 0
343          */
344         if (fmt[--fmt_size] != 0)
345                 return -EINVAL;
346
347         /* check format string for allowed specifiers */
348         for (i = 0; i < fmt_size; i++) {
349                 if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i]))
350                         return -EINVAL;
351
352                 if (fmt[i] != '%')
353                         continue;
354
355                 if (fmt_cnt >= 3)
356                         return -EINVAL;
357
358                 /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */
359                 i++;
360                 if (fmt[i] == 'l') {
361                         mod[fmt_cnt]++;
362                         i++;
363                 } else if (fmt[i] == 'p') {
364                         mod[fmt_cnt]++;
365                         if ((fmt[i + 1] == 'k' ||
366                              fmt[i + 1] == 'u') &&
367                             fmt[i + 2] == 's') {
368                                 fmt_ptype = fmt[i + 1];
369                                 i += 2;
370                                 goto fmt_str;
371                         }
372
373                         /* disallow any further format extensions */
374                         if (fmt[i + 1] != 0 &&
375                             !isspace(fmt[i + 1]) &&
376                             !ispunct(fmt[i + 1]))
377                                 return -EINVAL;
378
379                         goto fmt_next;
380                 } else if (fmt[i] == 's') {
381                         mod[fmt_cnt]++;
382                         fmt_ptype = fmt[i];
383 fmt_str:
384                         if (str_seen)
385                                 /* allow only one '%s' per fmt string */
386                                 return -EINVAL;
387                         str_seen = true;
388
389                         if (fmt[i + 1] != 0 &&
390                             !isspace(fmt[i + 1]) &&
391                             !ispunct(fmt[i + 1]))
392                                 return -EINVAL;
393
394                         switch (fmt_cnt) {
395                         case 0:
396                                 unsafe_ptr = (void *)(long)arg1;
397                                 arg1 = (long)buf;
398                                 break;
399                         case 1:
400                                 unsafe_ptr = (void *)(long)arg2;
401                                 arg2 = (long)buf;
402                                 break;
403                         case 2:
404                                 unsafe_ptr = (void *)(long)arg3;
405                                 arg3 = (long)buf;
406                                 break;
407                         }
408
409                         buf[0] = 0;
410                         switch (fmt_ptype) {
411                         case 's':
412 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
413                                 strncpy_from_unsafe(buf, unsafe_ptr,
414                                                     sizeof(buf));
415                                 break;
416 #endif
417                         case 'k':
418                                 strncpy_from_unsafe_strict(buf, unsafe_ptr,
419                                                            sizeof(buf));
420                                 break;
421                         case 'u':
422                                 strncpy_from_unsafe_user(buf,
423                                         (__force void __user *)unsafe_ptr,
424                                                          sizeof(buf));
425                                 break;
426                         }
427                         goto fmt_next;
428                 }
429
430                 if (fmt[i] == 'l') {
431                         mod[fmt_cnt]++;
432                         i++;
433                 }
434
435                 if (fmt[i] != 'i' && fmt[i] != 'd' &&
436                     fmt[i] != 'u' && fmt[i] != 'x')
437                         return -EINVAL;
438 fmt_next:
439                 fmt_cnt++;
440         }
441
442 /* Horrid workaround for getting va_list handling working with different
443  * argument type combinations generically for 32 and 64 bit archs.
444  */
445 #define __BPF_TP_EMIT() __BPF_ARG3_TP()
446 #define __BPF_TP(...)                                                   \
447         __trace_printk(0 /* Fake ip */,                                 \
448                        fmt, ##__VA_ARGS__)
449
450 #define __BPF_ARG1_TP(...)                                              \
451         ((mod[0] == 2 || (mod[0] == 1 && __BITS_PER_LONG == 64))        \
452           ? __BPF_TP(arg1, ##__VA_ARGS__)                               \
453           : ((mod[0] == 1 || (mod[0] == 0 && __BITS_PER_LONG == 32))    \
454               ? __BPF_TP((long)arg1, ##__VA_ARGS__)                     \
455               : __BPF_TP((u32)arg1, ##__VA_ARGS__)))
456
457 #define __BPF_ARG2_TP(...)                                              \
458         ((mod[1] == 2 || (mod[1] == 1 && __BITS_PER_LONG == 64))        \
459           ? __BPF_ARG1_TP(arg2, ##__VA_ARGS__)                          \
460           : ((mod[1] == 1 || (mod[1] == 0 && __BITS_PER_LONG == 32))    \
461               ? __BPF_ARG1_TP((long)arg2, ##__VA_ARGS__)                \
462               : __BPF_ARG1_TP((u32)arg2, ##__VA_ARGS__)))
463
464 #define __BPF_ARG3_TP(...)                                              \
465         ((mod[2] == 2 || (mod[2] == 1 && __BITS_PER_LONG == 64))        \
466           ? __BPF_ARG2_TP(arg3, ##__VA_ARGS__)                          \
467           : ((mod[2] == 1 || (mod[2] == 0 && __BITS_PER_LONG == 32))    \
468               ? __BPF_ARG2_TP((long)arg3, ##__VA_ARGS__)                \
469               : __BPF_ARG2_TP((u32)arg3, ##__VA_ARGS__)))
470
471         return __BPF_TP_EMIT();
472 }
473
474 static const struct bpf_func_proto bpf_trace_printk_proto = {
475         .func           = bpf_trace_printk,
476         .gpl_only       = true,
477         .ret_type       = RET_INTEGER,
478         .arg1_type      = ARG_PTR_TO_MEM,
479         .arg2_type      = ARG_CONST_SIZE,
480 };
481
482 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
483 {
484         /*
485          * this program might be calling bpf_trace_printk,
486          * so allocate per-cpu printk buffers
487          */
488         trace_printk_init_buffers();
489
490         return &bpf_trace_printk_proto;
491 }
492
493 #define MAX_SEQ_PRINTF_VARARGS          12
494 #define MAX_SEQ_PRINTF_MAX_MEMCPY       6
495 #define MAX_SEQ_PRINTF_STR_LEN          128
496
497 struct bpf_seq_printf_buf {
498         char buf[MAX_SEQ_PRINTF_MAX_MEMCPY][MAX_SEQ_PRINTF_STR_LEN];
499 };
500 static DEFINE_PER_CPU(struct bpf_seq_printf_buf, bpf_seq_printf_buf);
501 static DEFINE_PER_CPU(int, bpf_seq_printf_buf_used);
502
503 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
504            const void *, data, u32, data_len)
505 {
506         int err = -EINVAL, fmt_cnt = 0, memcpy_cnt = 0;
507         int i, buf_used, copy_size, num_args;
508         u64 params[MAX_SEQ_PRINTF_VARARGS];
509         struct bpf_seq_printf_buf *bufs;
510         const u64 *args = data;
511
512         buf_used = this_cpu_inc_return(bpf_seq_printf_buf_used);
513         if (WARN_ON_ONCE(buf_used > 1)) {
514                 err = -EBUSY;
515                 goto out;
516         }
517
518         bufs = this_cpu_ptr(&bpf_seq_printf_buf);
519
520         /*
521          * bpf_check()->check_func_arg()->check_stack_boundary()
522          * guarantees that fmt points to bpf program stack,
523          * fmt_size bytes of it were initialized and fmt_size > 0
524          */
525         if (fmt[--fmt_size] != 0)
526                 goto out;
527
528         if (data_len & 7)
529                 goto out;
530
531         for (i = 0; i < fmt_size; i++) {
532                 if (fmt[i] == '%') {
533                         if (fmt[i + 1] == '%')
534                                 i++;
535                         else if (!data || !data_len)
536                                 goto out;
537                 }
538         }
539
540         num_args = data_len / 8;
541
542         /* check format string for allowed specifiers */
543         for (i = 0; i < fmt_size; i++) {
544                 /* only printable ascii for now. */
545                 if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i])) {
546                         err = -EINVAL;
547                         goto out;
548                 }
549
550                 if (fmt[i] != '%')
551                         continue;
552
553                 if (fmt[i + 1] == '%') {
554                         i++;
555                         continue;
556                 }
557
558                 if (fmt_cnt >= MAX_SEQ_PRINTF_VARARGS) {
559                         err = -E2BIG;
560                         goto out;
561                 }
562
563                 if (fmt_cnt >= num_args) {
564                         err = -EINVAL;
565                         goto out;
566                 }
567
568                 /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */
569                 i++;
570
571                 /* skip optional "[0 +-][num]" width formating field */
572                 while (fmt[i] == '0' || fmt[i] == '+'  || fmt[i] == '-' ||
573                        fmt[i] == ' ')
574                         i++;
575                 if (fmt[i] >= '1' && fmt[i] <= '9') {
576                         i++;
577                         while (fmt[i] >= '0' && fmt[i] <= '9')
578                                 i++;
579                 }
580
581                 if (fmt[i] == 's') {
582                         /* try our best to copy */
583                         if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) {
584                                 err = -E2BIG;
585                                 goto out;
586                         }
587
588                         err = strncpy_from_unsafe(bufs->buf[memcpy_cnt],
589                                                   (void *) (long) args[fmt_cnt],
590                                                   MAX_SEQ_PRINTF_STR_LEN);
591                         if (err < 0)
592                                 bufs->buf[memcpy_cnt][0] = '\0';
593                         params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt];
594
595                         fmt_cnt++;
596                         memcpy_cnt++;
597                         continue;
598                 }
599
600                 if (fmt[i] == 'p') {
601                         if (fmt[i + 1] == 0 ||
602                             fmt[i + 1] == 'K' ||
603                             fmt[i + 1] == 'x') {
604                                 /* just kernel pointers */
605                                 params[fmt_cnt] = args[fmt_cnt];
606                                 fmt_cnt++;
607                                 continue;
608                         }
609
610                         /* only support "%pI4", "%pi4", "%pI6" and "%pi6". */
611                         if (fmt[i + 1] != 'i' && fmt[i + 1] != 'I') {
612                                 err = -EINVAL;
613                                 goto out;
614                         }
615                         if (fmt[i + 2] != '4' && fmt[i + 2] != '6') {
616                                 err = -EINVAL;
617                                 goto out;
618                         }
619
620                         if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) {
621                                 err = -E2BIG;
622                                 goto out;
623                         }
624
625
626                         copy_size = (fmt[i + 2] == '4') ? 4 : 16;
627
628                         err = probe_kernel_read(bufs->buf[memcpy_cnt],
629                                                 (void *) (long) args[fmt_cnt],
630                                                 copy_size);
631                         if (err < 0)
632                                 memset(bufs->buf[memcpy_cnt], 0, copy_size);
633                         params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt];
634
635                         i += 2;
636                         fmt_cnt++;
637                         memcpy_cnt++;
638                         continue;
639                 }
640
641                 if (fmt[i] == 'l') {
642                         i++;
643                         if (fmt[i] == 'l')
644                                 i++;
645                 }
646
647                 if (fmt[i] != 'i' && fmt[i] != 'd' &&
648                     fmt[i] != 'u' && fmt[i] != 'x') {
649                         err = -EINVAL;
650                         goto out;
651                 }
652
653                 params[fmt_cnt] = args[fmt_cnt];
654                 fmt_cnt++;
655         }
656
657         /* Maximumly we can have MAX_SEQ_PRINTF_VARARGS parameter, just give
658          * all of them to seq_printf().
659          */
660         seq_printf(m, fmt, params[0], params[1], params[2], params[3],
661                    params[4], params[5], params[6], params[7], params[8],
662                    params[9], params[10], params[11]);
663
664         err = seq_has_overflowed(m) ? -EOVERFLOW : 0;
665 out:
666         this_cpu_dec(bpf_seq_printf_buf_used);
667         return err;
668 }
669
670 static int bpf_seq_printf_btf_ids[5];
671 static const struct bpf_func_proto bpf_seq_printf_proto = {
672         .func           = bpf_seq_printf,
673         .gpl_only       = true,
674         .ret_type       = RET_INTEGER,
675         .arg1_type      = ARG_PTR_TO_BTF_ID,
676         .arg2_type      = ARG_PTR_TO_MEM,
677         .arg3_type      = ARG_CONST_SIZE,
678         .arg4_type      = ARG_PTR_TO_MEM_OR_NULL,
679         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
680         .btf_id         = bpf_seq_printf_btf_ids,
681 };
682
683 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
684 {
685         return seq_write(m, data, len) ? -EOVERFLOW : 0;
686 }
687
688 static int bpf_seq_write_btf_ids[5];
689 static const struct bpf_func_proto bpf_seq_write_proto = {
690         .func           = bpf_seq_write,
691         .gpl_only       = true,
692         .ret_type       = RET_INTEGER,
693         .arg1_type      = ARG_PTR_TO_BTF_ID,
694         .arg2_type      = ARG_PTR_TO_MEM,
695         .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
696         .btf_id         = bpf_seq_write_btf_ids,
697 };
698
699 static __always_inline int
700 get_map_perf_counter(struct bpf_map *map, u64 flags,
701                      u64 *value, u64 *enabled, u64 *running)
702 {
703         struct bpf_array *array = container_of(map, struct bpf_array, map);
704         unsigned int cpu = smp_processor_id();
705         u64 index = flags & BPF_F_INDEX_MASK;
706         struct bpf_event_entry *ee;
707
708         if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
709                 return -EINVAL;
710         if (index == BPF_F_CURRENT_CPU)
711                 index = cpu;
712         if (unlikely(index >= array->map.max_entries))
713                 return -E2BIG;
714
715         ee = READ_ONCE(array->ptrs[index]);
716         if (!ee)
717                 return -ENOENT;
718
719         return perf_event_read_local(ee->event, value, enabled, running);
720 }
721
722 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
723 {
724         u64 value = 0;
725         int err;
726
727         err = get_map_perf_counter(map, flags, &value, NULL, NULL);
728         /*
729          * this api is ugly since we miss [-22..-2] range of valid
730          * counter values, but that's uapi
731          */
732         if (err)
733                 return err;
734         return value;
735 }
736
737 static const struct bpf_func_proto bpf_perf_event_read_proto = {
738         .func           = bpf_perf_event_read,
739         .gpl_only       = true,
740         .ret_type       = RET_INTEGER,
741         .arg1_type      = ARG_CONST_MAP_PTR,
742         .arg2_type      = ARG_ANYTHING,
743 };
744
745 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
746            struct bpf_perf_event_value *, buf, u32, size)
747 {
748         int err = -EINVAL;
749
750         if (unlikely(size != sizeof(struct bpf_perf_event_value)))
751                 goto clear;
752         err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
753                                    &buf->running);
754         if (unlikely(err))
755                 goto clear;
756         return 0;
757 clear:
758         memset(buf, 0, size);
759         return err;
760 }
761
762 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
763         .func           = bpf_perf_event_read_value,
764         .gpl_only       = true,
765         .ret_type       = RET_INTEGER,
766         .arg1_type      = ARG_CONST_MAP_PTR,
767         .arg2_type      = ARG_ANYTHING,
768         .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
769         .arg4_type      = ARG_CONST_SIZE,
770 };
771
772 static __always_inline u64
773 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
774                         u64 flags, struct perf_sample_data *sd)
775 {
776         struct bpf_array *array = container_of(map, struct bpf_array, map);
777         unsigned int cpu = smp_processor_id();
778         u64 index = flags & BPF_F_INDEX_MASK;
779         struct bpf_event_entry *ee;
780         struct perf_event *event;
781
782         if (index == BPF_F_CURRENT_CPU)
783                 index = cpu;
784         if (unlikely(index >= array->map.max_entries))
785                 return -E2BIG;
786
787         ee = READ_ONCE(array->ptrs[index]);
788         if (!ee)
789                 return -ENOENT;
790
791         event = ee->event;
792         if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
793                      event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
794                 return -EINVAL;
795
796         if (unlikely(event->oncpu != cpu))
797                 return -EOPNOTSUPP;
798
799         return perf_event_output(event, sd, regs);
800 }
801
802 /*
803  * Support executing tracepoints in normal, irq, and nmi context that each call
804  * bpf_perf_event_output
805  */
806 struct bpf_trace_sample_data {
807         struct perf_sample_data sds[3];
808 };
809
810 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
811 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
812 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
813            u64, flags, void *, data, u64, size)
814 {
815         struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds);
816         int nest_level = this_cpu_inc_return(bpf_trace_nest_level);
817         struct perf_raw_record raw = {
818                 .frag = {
819                         .size = size,
820                         .data = data,
821                 },
822         };
823         struct perf_sample_data *sd;
824         int err;
825
826         if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
827                 err = -EBUSY;
828                 goto out;
829         }
830
831         sd = &sds->sds[nest_level - 1];
832
833         if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
834                 err = -EINVAL;
835                 goto out;
836         }
837
838         perf_sample_data_init(sd, 0, 0);
839         sd->raw = &raw;
840
841         err = __bpf_perf_event_output(regs, map, flags, sd);
842
843 out:
844         this_cpu_dec(bpf_trace_nest_level);
845         return err;
846 }
847
848 static const struct bpf_func_proto bpf_perf_event_output_proto = {
849         .func           = bpf_perf_event_output,
850         .gpl_only       = true,
851         .ret_type       = RET_INTEGER,
852         .arg1_type      = ARG_PTR_TO_CTX,
853         .arg2_type      = ARG_CONST_MAP_PTR,
854         .arg3_type      = ARG_ANYTHING,
855         .arg4_type      = ARG_PTR_TO_MEM,
856         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
857 };
858
859 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
860 struct bpf_nested_pt_regs {
861         struct pt_regs regs[3];
862 };
863 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
864 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
865
866 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
867                      void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
868 {
869         int nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
870         struct perf_raw_frag frag = {
871                 .copy           = ctx_copy,
872                 .size           = ctx_size,
873                 .data           = ctx,
874         };
875         struct perf_raw_record raw = {
876                 .frag = {
877                         {
878                                 .next   = ctx_size ? &frag : NULL,
879                         },
880                         .size   = meta_size,
881                         .data   = meta,
882                 },
883         };
884         struct perf_sample_data *sd;
885         struct pt_regs *regs;
886         u64 ret;
887
888         if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
889                 ret = -EBUSY;
890                 goto out;
891         }
892         sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
893         regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
894
895         perf_fetch_caller_regs(regs);
896         perf_sample_data_init(sd, 0, 0);
897         sd->raw = &raw;
898
899         ret = __bpf_perf_event_output(regs, map, flags, sd);
900 out:
901         this_cpu_dec(bpf_event_output_nest_level);
902         return ret;
903 }
904
905 BPF_CALL_0(bpf_get_current_task)
906 {
907         return (long) current;
908 }
909
910 const struct bpf_func_proto bpf_get_current_task_proto = {
911         .func           = bpf_get_current_task,
912         .gpl_only       = true,
913         .ret_type       = RET_INTEGER,
914 };
915
916 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
917 {
918         struct bpf_array *array = container_of(map, struct bpf_array, map);
919         struct cgroup *cgrp;
920
921         if (unlikely(idx >= array->map.max_entries))
922                 return -E2BIG;
923
924         cgrp = READ_ONCE(array->ptrs[idx]);
925         if (unlikely(!cgrp))
926                 return -EAGAIN;
927
928         return task_under_cgroup_hierarchy(current, cgrp);
929 }
930
931 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
932         .func           = bpf_current_task_under_cgroup,
933         .gpl_only       = false,
934         .ret_type       = RET_INTEGER,
935         .arg1_type      = ARG_CONST_MAP_PTR,
936         .arg2_type      = ARG_ANYTHING,
937 };
938
939 struct send_signal_irq_work {
940         struct irq_work irq_work;
941         struct task_struct *task;
942         u32 sig;
943         enum pid_type type;
944 };
945
946 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
947
948 static void do_bpf_send_signal(struct irq_work *entry)
949 {
950         struct send_signal_irq_work *work;
951
952         work = container_of(entry, struct send_signal_irq_work, irq_work);
953         group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
954 }
955
956 static int bpf_send_signal_common(u32 sig, enum pid_type type)
957 {
958         struct send_signal_irq_work *work = NULL;
959
960         /* Similar to bpf_probe_write_user, task needs to be
961          * in a sound condition and kernel memory access be
962          * permitted in order to send signal to the current
963          * task.
964          */
965         if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
966                 return -EPERM;
967         if (unlikely(uaccess_kernel()))
968                 return -EPERM;
969         if (unlikely(!nmi_uaccess_okay()))
970                 return -EPERM;
971
972         if (irqs_disabled()) {
973                 /* Do an early check on signal validity. Otherwise,
974                  * the error is lost in deferred irq_work.
975                  */
976                 if (unlikely(!valid_signal(sig)))
977                         return -EINVAL;
978
979                 work = this_cpu_ptr(&send_signal_work);
980                 if (atomic_read(&work->irq_work.flags) & IRQ_WORK_BUSY)
981                         return -EBUSY;
982
983                 /* Add the current task, which is the target of sending signal,
984                  * to the irq_work. The current task may change when queued
985                  * irq works get executed.
986                  */
987                 work->task = current;
988                 work->sig = sig;
989                 work->type = type;
990                 irq_work_queue(&work->irq_work);
991                 return 0;
992         }
993
994         return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
995 }
996
997 BPF_CALL_1(bpf_send_signal, u32, sig)
998 {
999         return bpf_send_signal_common(sig, PIDTYPE_TGID);
1000 }
1001
1002 static const struct bpf_func_proto bpf_send_signal_proto = {
1003         .func           = bpf_send_signal,
1004         .gpl_only       = false,
1005         .ret_type       = RET_INTEGER,
1006         .arg1_type      = ARG_ANYTHING,
1007 };
1008
1009 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
1010 {
1011         return bpf_send_signal_common(sig, PIDTYPE_PID);
1012 }
1013
1014 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
1015         .func           = bpf_send_signal_thread,
1016         .gpl_only       = false,
1017         .ret_type       = RET_INTEGER,
1018         .arg1_type      = ARG_ANYTHING,
1019 };
1020
1021 const struct bpf_func_proto *
1022 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1023 {
1024         switch (func_id) {
1025         case BPF_FUNC_map_lookup_elem:
1026                 return &bpf_map_lookup_elem_proto;
1027         case BPF_FUNC_map_update_elem:
1028                 return &bpf_map_update_elem_proto;
1029         case BPF_FUNC_map_delete_elem:
1030                 return &bpf_map_delete_elem_proto;
1031         case BPF_FUNC_map_push_elem:
1032                 return &bpf_map_push_elem_proto;
1033         case BPF_FUNC_map_pop_elem:
1034                 return &bpf_map_pop_elem_proto;
1035         case BPF_FUNC_map_peek_elem:
1036                 return &bpf_map_peek_elem_proto;
1037         case BPF_FUNC_ktime_get_ns:
1038                 return &bpf_ktime_get_ns_proto;
1039         case BPF_FUNC_ktime_get_boot_ns:
1040                 return &bpf_ktime_get_boot_ns_proto;
1041         case BPF_FUNC_tail_call:
1042                 return &bpf_tail_call_proto;
1043         case BPF_FUNC_get_current_pid_tgid:
1044                 return &bpf_get_current_pid_tgid_proto;
1045         case BPF_FUNC_get_current_task:
1046                 return &bpf_get_current_task_proto;
1047         case BPF_FUNC_get_current_uid_gid:
1048                 return &bpf_get_current_uid_gid_proto;
1049         case BPF_FUNC_get_current_comm:
1050                 return &bpf_get_current_comm_proto;
1051         case BPF_FUNC_trace_printk:
1052                 return bpf_get_trace_printk_proto();
1053         case BPF_FUNC_get_smp_processor_id:
1054                 return &bpf_get_smp_processor_id_proto;
1055         case BPF_FUNC_get_numa_node_id:
1056                 return &bpf_get_numa_node_id_proto;
1057         case BPF_FUNC_perf_event_read:
1058                 return &bpf_perf_event_read_proto;
1059         case BPF_FUNC_probe_write_user:
1060                 return bpf_get_probe_write_proto();
1061         case BPF_FUNC_current_task_under_cgroup:
1062                 return &bpf_current_task_under_cgroup_proto;
1063         case BPF_FUNC_get_prandom_u32:
1064                 return &bpf_get_prandom_u32_proto;
1065         case BPF_FUNC_probe_read_user:
1066                 return &bpf_probe_read_user_proto;
1067         case BPF_FUNC_probe_read_kernel:
1068                 return &bpf_probe_read_kernel_proto;
1069         case BPF_FUNC_probe_read_user_str:
1070                 return &bpf_probe_read_user_str_proto;
1071         case BPF_FUNC_probe_read_kernel_str:
1072                 return &bpf_probe_read_kernel_str_proto;
1073 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1074         case BPF_FUNC_probe_read:
1075                 return &bpf_probe_read_compat_proto;
1076         case BPF_FUNC_probe_read_str:
1077                 return &bpf_probe_read_compat_str_proto;
1078 #endif
1079 #ifdef CONFIG_CGROUPS
1080         case BPF_FUNC_get_current_cgroup_id:
1081                 return &bpf_get_current_cgroup_id_proto;
1082 #endif
1083         case BPF_FUNC_send_signal:
1084                 return &bpf_send_signal_proto;
1085         case BPF_FUNC_send_signal_thread:
1086                 return &bpf_send_signal_thread_proto;
1087         case BPF_FUNC_perf_event_read_value:
1088                 return &bpf_perf_event_read_value_proto;
1089         case BPF_FUNC_get_ns_current_pid_tgid:
1090                 return &bpf_get_ns_current_pid_tgid_proto;
1091         default:
1092                 return NULL;
1093         }
1094 }
1095
1096 static const struct bpf_func_proto *
1097 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1098 {
1099         switch (func_id) {
1100         case BPF_FUNC_perf_event_output:
1101                 return &bpf_perf_event_output_proto;
1102         case BPF_FUNC_get_stackid:
1103                 return &bpf_get_stackid_proto;
1104         case BPF_FUNC_get_stack:
1105                 return &bpf_get_stack_proto;
1106 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1107         case BPF_FUNC_override_return:
1108                 return &bpf_override_return_proto;
1109 #endif
1110         default:
1111                 return bpf_tracing_func_proto(func_id, prog);
1112         }
1113 }
1114
1115 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
1116 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1117                                         const struct bpf_prog *prog,
1118                                         struct bpf_insn_access_aux *info)
1119 {
1120         if (off < 0 || off >= sizeof(struct pt_regs))
1121                 return false;
1122         if (type != BPF_READ)
1123                 return false;
1124         if (off % size != 0)
1125                 return false;
1126         /*
1127          * Assertion for 32 bit to make sure last 8 byte access
1128          * (BPF_DW) to the last 4 byte member is disallowed.
1129          */
1130         if (off + size > sizeof(struct pt_regs))
1131                 return false;
1132
1133         return true;
1134 }
1135
1136 const struct bpf_verifier_ops kprobe_verifier_ops = {
1137         .get_func_proto  = kprobe_prog_func_proto,
1138         .is_valid_access = kprobe_prog_is_valid_access,
1139 };
1140
1141 const struct bpf_prog_ops kprobe_prog_ops = {
1142 };
1143
1144 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1145            u64, flags, void *, data, u64, size)
1146 {
1147         struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1148
1149         /*
1150          * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1151          * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1152          * from there and call the same bpf_perf_event_output() helper inline.
1153          */
1154         return ____bpf_perf_event_output(regs, map, flags, data, size);
1155 }
1156
1157 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1158         .func           = bpf_perf_event_output_tp,
1159         .gpl_only       = true,
1160         .ret_type       = RET_INTEGER,
1161         .arg1_type      = ARG_PTR_TO_CTX,
1162         .arg2_type      = ARG_CONST_MAP_PTR,
1163         .arg3_type      = ARG_ANYTHING,
1164         .arg4_type      = ARG_PTR_TO_MEM,
1165         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
1166 };
1167
1168 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1169            u64, flags)
1170 {
1171         struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1172
1173         /*
1174          * Same comment as in bpf_perf_event_output_tp(), only that this time
1175          * the other helper's function body cannot be inlined due to being
1176          * external, thus we need to call raw helper function.
1177          */
1178         return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1179                                flags, 0, 0);
1180 }
1181
1182 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1183         .func           = bpf_get_stackid_tp,
1184         .gpl_only       = true,
1185         .ret_type       = RET_INTEGER,
1186         .arg1_type      = ARG_PTR_TO_CTX,
1187         .arg2_type      = ARG_CONST_MAP_PTR,
1188         .arg3_type      = ARG_ANYTHING,
1189 };
1190
1191 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1192            u64, flags)
1193 {
1194         struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1195
1196         return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1197                              (unsigned long) size, flags, 0);
1198 }
1199
1200 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1201         .func           = bpf_get_stack_tp,
1202         .gpl_only       = true,
1203         .ret_type       = RET_INTEGER,
1204         .arg1_type      = ARG_PTR_TO_CTX,
1205         .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
1206         .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
1207         .arg4_type      = ARG_ANYTHING,
1208 };
1209
1210 static const struct bpf_func_proto *
1211 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1212 {
1213         switch (func_id) {
1214         case BPF_FUNC_perf_event_output:
1215                 return &bpf_perf_event_output_proto_tp;
1216         case BPF_FUNC_get_stackid:
1217                 return &bpf_get_stackid_proto_tp;
1218         case BPF_FUNC_get_stack:
1219                 return &bpf_get_stack_proto_tp;
1220         default:
1221                 return bpf_tracing_func_proto(func_id, prog);
1222         }
1223 }
1224
1225 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1226                                     const struct bpf_prog *prog,
1227                                     struct bpf_insn_access_aux *info)
1228 {
1229         if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1230                 return false;
1231         if (type != BPF_READ)
1232                 return false;
1233         if (off % size != 0)
1234                 return false;
1235
1236         BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1237         return true;
1238 }
1239
1240 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1241         .get_func_proto  = tp_prog_func_proto,
1242         .is_valid_access = tp_prog_is_valid_access,
1243 };
1244
1245 const struct bpf_prog_ops tracepoint_prog_ops = {
1246 };
1247
1248 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1249            struct bpf_perf_event_value *, buf, u32, size)
1250 {
1251         int err = -EINVAL;
1252
1253         if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1254                 goto clear;
1255         err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1256                                     &buf->running);
1257         if (unlikely(err))
1258                 goto clear;
1259         return 0;
1260 clear:
1261         memset(buf, 0, size);
1262         return err;
1263 }
1264
1265 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1266          .func           = bpf_perf_prog_read_value,
1267          .gpl_only       = true,
1268          .ret_type       = RET_INTEGER,
1269          .arg1_type      = ARG_PTR_TO_CTX,
1270          .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
1271          .arg3_type      = ARG_CONST_SIZE,
1272 };
1273
1274 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1275            void *, buf, u32, size, u64, flags)
1276 {
1277 #ifndef CONFIG_X86
1278         return -ENOENT;
1279 #else
1280         static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1281         struct perf_branch_stack *br_stack = ctx->data->br_stack;
1282         u32 to_copy;
1283
1284         if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1285                 return -EINVAL;
1286
1287         if (unlikely(!br_stack))
1288                 return -EINVAL;
1289
1290         if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1291                 return br_stack->nr * br_entry_size;
1292
1293         if (!buf || (size % br_entry_size != 0))
1294                 return -EINVAL;
1295
1296         to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1297         memcpy(buf, br_stack->entries, to_copy);
1298
1299         return to_copy;
1300 #endif
1301 }
1302
1303 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1304         .func           = bpf_read_branch_records,
1305         .gpl_only       = true,
1306         .ret_type       = RET_INTEGER,
1307         .arg1_type      = ARG_PTR_TO_CTX,
1308         .arg2_type      = ARG_PTR_TO_MEM_OR_NULL,
1309         .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
1310         .arg4_type      = ARG_ANYTHING,
1311 };
1312
1313 static const struct bpf_func_proto *
1314 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1315 {
1316         switch (func_id) {
1317         case BPF_FUNC_perf_event_output:
1318                 return &bpf_perf_event_output_proto_tp;
1319         case BPF_FUNC_get_stackid:
1320                 return &bpf_get_stackid_proto_tp;
1321         case BPF_FUNC_get_stack:
1322                 return &bpf_get_stack_proto_tp;
1323         case BPF_FUNC_perf_prog_read_value:
1324                 return &bpf_perf_prog_read_value_proto;
1325         case BPF_FUNC_read_branch_records:
1326                 return &bpf_read_branch_records_proto;
1327         default:
1328                 return bpf_tracing_func_proto(func_id, prog);
1329         }
1330 }
1331
1332 /*
1333  * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1334  * to avoid potential recursive reuse issue when/if tracepoints are added
1335  * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1336  *
1337  * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1338  * in normal, irq, and nmi context.
1339  */
1340 struct bpf_raw_tp_regs {
1341         struct pt_regs regs[3];
1342 };
1343 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1344 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
1345 static struct pt_regs *get_bpf_raw_tp_regs(void)
1346 {
1347         struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1348         int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1349
1350         if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1351                 this_cpu_dec(bpf_raw_tp_nest_level);
1352                 return ERR_PTR(-EBUSY);
1353         }
1354
1355         return &tp_regs->regs[nest_level - 1];
1356 }
1357
1358 static void put_bpf_raw_tp_regs(void)
1359 {
1360         this_cpu_dec(bpf_raw_tp_nest_level);
1361 }
1362
1363 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1364            struct bpf_map *, map, u64, flags, void *, data, u64, size)
1365 {
1366         struct pt_regs *regs = get_bpf_raw_tp_regs();
1367         int ret;
1368
1369         if (IS_ERR(regs))
1370                 return PTR_ERR(regs);
1371
1372         perf_fetch_caller_regs(regs);
1373         ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1374
1375         put_bpf_raw_tp_regs();
1376         return ret;
1377 }
1378
1379 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1380         .func           = bpf_perf_event_output_raw_tp,
1381         .gpl_only       = true,
1382         .ret_type       = RET_INTEGER,
1383         .arg1_type      = ARG_PTR_TO_CTX,
1384         .arg2_type      = ARG_CONST_MAP_PTR,
1385         .arg3_type      = ARG_ANYTHING,
1386         .arg4_type      = ARG_PTR_TO_MEM,
1387         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
1388 };
1389
1390 extern const struct bpf_func_proto bpf_skb_output_proto;
1391 extern const struct bpf_func_proto bpf_xdp_output_proto;
1392
1393 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1394            struct bpf_map *, map, u64, flags)
1395 {
1396         struct pt_regs *regs = get_bpf_raw_tp_regs();
1397         int ret;
1398
1399         if (IS_ERR(regs))
1400                 return PTR_ERR(regs);
1401
1402         perf_fetch_caller_regs(regs);
1403         /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1404         ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1405                               flags, 0, 0);
1406         put_bpf_raw_tp_regs();
1407         return ret;
1408 }
1409
1410 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1411         .func           = bpf_get_stackid_raw_tp,
1412         .gpl_only       = true,
1413         .ret_type       = RET_INTEGER,
1414         .arg1_type      = ARG_PTR_TO_CTX,
1415         .arg2_type      = ARG_CONST_MAP_PTR,
1416         .arg3_type      = ARG_ANYTHING,
1417 };
1418
1419 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1420            void *, buf, u32, size, u64, flags)
1421 {
1422         struct pt_regs *regs = get_bpf_raw_tp_regs();
1423         int ret;
1424
1425         if (IS_ERR(regs))
1426                 return PTR_ERR(regs);
1427
1428         perf_fetch_caller_regs(regs);
1429         ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1430                             (unsigned long) size, flags, 0);
1431         put_bpf_raw_tp_regs();
1432         return ret;
1433 }
1434
1435 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1436         .func           = bpf_get_stack_raw_tp,
1437         .gpl_only       = true,
1438         .ret_type       = RET_INTEGER,
1439         .arg1_type      = ARG_PTR_TO_CTX,
1440         .arg2_type      = ARG_PTR_TO_MEM,
1441         .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
1442         .arg4_type      = ARG_ANYTHING,
1443 };
1444
1445 static const struct bpf_func_proto *
1446 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1447 {
1448         switch (func_id) {
1449         case BPF_FUNC_perf_event_output:
1450                 return &bpf_perf_event_output_proto_raw_tp;
1451         case BPF_FUNC_get_stackid:
1452                 return &bpf_get_stackid_proto_raw_tp;
1453         case BPF_FUNC_get_stack:
1454                 return &bpf_get_stack_proto_raw_tp;
1455         default:
1456                 return bpf_tracing_func_proto(func_id, prog);
1457         }
1458 }
1459
1460 static const struct bpf_func_proto *
1461 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1462 {
1463         switch (func_id) {
1464 #ifdef CONFIG_NET
1465         case BPF_FUNC_skb_output:
1466                 return &bpf_skb_output_proto;
1467         case BPF_FUNC_xdp_output:
1468                 return &bpf_xdp_output_proto;
1469 #endif
1470         case BPF_FUNC_seq_printf:
1471                 return prog->expected_attach_type == BPF_TRACE_ITER ?
1472                        &bpf_seq_printf_proto :
1473                        NULL;
1474         case BPF_FUNC_seq_write:
1475                 return prog->expected_attach_type == BPF_TRACE_ITER ?
1476                        &bpf_seq_write_proto :
1477                        NULL;
1478         default:
1479                 return raw_tp_prog_func_proto(func_id, prog);
1480         }
1481 }
1482
1483 static bool raw_tp_prog_is_valid_access(int off, int size,
1484                                         enum bpf_access_type type,
1485                                         const struct bpf_prog *prog,
1486                                         struct bpf_insn_access_aux *info)
1487 {
1488         if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
1489                 return false;
1490         if (type != BPF_READ)
1491                 return false;
1492         if (off % size != 0)
1493                 return false;
1494         return true;
1495 }
1496
1497 static bool tracing_prog_is_valid_access(int off, int size,
1498                                          enum bpf_access_type type,
1499                                          const struct bpf_prog *prog,
1500                                          struct bpf_insn_access_aux *info)
1501 {
1502         if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
1503                 return false;
1504         if (type != BPF_READ)
1505                 return false;
1506         if (off % size != 0)
1507                 return false;
1508         return btf_ctx_access(off, size, type, prog, info);
1509 }
1510
1511 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
1512                                      const union bpf_attr *kattr,
1513                                      union bpf_attr __user *uattr)
1514 {
1515         return -ENOTSUPP;
1516 }
1517
1518 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
1519         .get_func_proto  = raw_tp_prog_func_proto,
1520         .is_valid_access = raw_tp_prog_is_valid_access,
1521 };
1522
1523 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
1524 };
1525
1526 const struct bpf_verifier_ops tracing_verifier_ops = {
1527         .get_func_proto  = tracing_prog_func_proto,
1528         .is_valid_access = tracing_prog_is_valid_access,
1529 };
1530
1531 const struct bpf_prog_ops tracing_prog_ops = {
1532         .test_run = bpf_prog_test_run_tracing,
1533 };
1534
1535 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
1536                                                  enum bpf_access_type type,
1537                                                  const struct bpf_prog *prog,
1538                                                  struct bpf_insn_access_aux *info)
1539 {
1540         if (off == 0) {
1541                 if (size != sizeof(u64) || type != BPF_READ)
1542                         return false;
1543                 info->reg_type = PTR_TO_TP_BUFFER;
1544         }
1545         return raw_tp_prog_is_valid_access(off, size, type, prog, info);
1546 }
1547
1548 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
1549         .get_func_proto  = raw_tp_prog_func_proto,
1550         .is_valid_access = raw_tp_writable_prog_is_valid_access,
1551 };
1552
1553 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
1554 };
1555
1556 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1557                                     const struct bpf_prog *prog,
1558                                     struct bpf_insn_access_aux *info)
1559 {
1560         const int size_u64 = sizeof(u64);
1561
1562         if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
1563                 return false;
1564         if (type != BPF_READ)
1565                 return false;
1566         if (off % size != 0) {
1567                 if (sizeof(unsigned long) != 4)
1568                         return false;
1569                 if (size != 8)
1570                         return false;
1571                 if (off % size != 4)
1572                         return false;
1573         }
1574
1575         switch (off) {
1576         case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
1577                 bpf_ctx_record_field_size(info, size_u64);
1578                 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1579                         return false;
1580                 break;
1581         case bpf_ctx_range(struct bpf_perf_event_data, addr):
1582                 bpf_ctx_record_field_size(info, size_u64);
1583                 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1584                         return false;
1585                 break;
1586         default:
1587                 if (size != sizeof(long))
1588                         return false;
1589         }
1590
1591         return true;
1592 }
1593
1594 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
1595                                       const struct bpf_insn *si,
1596                                       struct bpf_insn *insn_buf,
1597                                       struct bpf_prog *prog, u32 *target_size)
1598 {
1599         struct bpf_insn *insn = insn_buf;
1600
1601         switch (si->off) {
1602         case offsetof(struct bpf_perf_event_data, sample_period):
1603                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1604                                                        data), si->dst_reg, si->src_reg,
1605                                       offsetof(struct bpf_perf_event_data_kern, data));
1606                 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1607                                       bpf_target_off(struct perf_sample_data, period, 8,
1608                                                      target_size));
1609                 break;
1610         case offsetof(struct bpf_perf_event_data, addr):
1611                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1612                                                        data), si->dst_reg, si->src_reg,
1613                                       offsetof(struct bpf_perf_event_data_kern, data));
1614                 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1615                                       bpf_target_off(struct perf_sample_data, addr, 8,
1616                                                      target_size));
1617                 break;
1618         default:
1619                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1620                                                        regs), si->dst_reg, si->src_reg,
1621                                       offsetof(struct bpf_perf_event_data_kern, regs));
1622                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
1623                                       si->off);
1624                 break;
1625         }
1626
1627         return insn - insn_buf;
1628 }
1629
1630 const struct bpf_verifier_ops perf_event_verifier_ops = {
1631         .get_func_proto         = pe_prog_func_proto,
1632         .is_valid_access        = pe_prog_is_valid_access,
1633         .convert_ctx_access     = pe_prog_convert_ctx_access,
1634 };
1635
1636 const struct bpf_prog_ops perf_event_prog_ops = {
1637 };
1638
1639 static DEFINE_MUTEX(bpf_event_mutex);
1640
1641 #define BPF_TRACE_MAX_PROGS 64
1642
1643 int perf_event_attach_bpf_prog(struct perf_event *event,
1644                                struct bpf_prog *prog)
1645 {
1646         struct bpf_prog_array *old_array;
1647         struct bpf_prog_array *new_array;
1648         int ret = -EEXIST;
1649
1650         /*
1651          * Kprobe override only works if they are on the function entry,
1652          * and only if they are on the opt-in list.
1653          */
1654         if (prog->kprobe_override &&
1655             (!trace_kprobe_on_func_entry(event->tp_event) ||
1656              !trace_kprobe_error_injectable(event->tp_event)))
1657                 return -EINVAL;
1658
1659         mutex_lock(&bpf_event_mutex);
1660
1661         if (event->prog)
1662                 goto unlock;
1663
1664         old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1665         if (old_array &&
1666             bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
1667                 ret = -E2BIG;
1668                 goto unlock;
1669         }
1670
1671         ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array);
1672         if (ret < 0)
1673                 goto unlock;
1674
1675         /* set the new array to event->tp_event and set event->prog */
1676         event->prog = prog;
1677         rcu_assign_pointer(event->tp_event->prog_array, new_array);
1678         bpf_prog_array_free(old_array);
1679
1680 unlock:
1681         mutex_unlock(&bpf_event_mutex);
1682         return ret;
1683 }
1684
1685 void perf_event_detach_bpf_prog(struct perf_event *event)
1686 {
1687         struct bpf_prog_array *old_array;
1688         struct bpf_prog_array *new_array;
1689         int ret;
1690
1691         mutex_lock(&bpf_event_mutex);
1692
1693         if (!event->prog)
1694                 goto unlock;
1695
1696         old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1697         ret = bpf_prog_array_copy(old_array, event->prog, NULL, &new_array);
1698         if (ret == -ENOENT)
1699                 goto unlock;
1700         if (ret < 0) {
1701                 bpf_prog_array_delete_safe(old_array, event->prog);
1702         } else {
1703                 rcu_assign_pointer(event->tp_event->prog_array, new_array);
1704                 bpf_prog_array_free(old_array);
1705         }
1706
1707         bpf_prog_put(event->prog);
1708         event->prog = NULL;
1709
1710 unlock:
1711         mutex_unlock(&bpf_event_mutex);
1712 }
1713
1714 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
1715 {
1716         struct perf_event_query_bpf __user *uquery = info;
1717         struct perf_event_query_bpf query = {};
1718         struct bpf_prog_array *progs;
1719         u32 *ids, prog_cnt, ids_len;
1720         int ret;
1721
1722         if (!capable(CAP_SYS_ADMIN))
1723                 return -EPERM;
1724         if (event->attr.type != PERF_TYPE_TRACEPOINT)
1725                 return -EINVAL;
1726         if (copy_from_user(&query, uquery, sizeof(query)))
1727                 return -EFAULT;
1728
1729         ids_len = query.ids_len;
1730         if (ids_len > BPF_TRACE_MAX_PROGS)
1731                 return -E2BIG;
1732         ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
1733         if (!ids)
1734                 return -ENOMEM;
1735         /*
1736          * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
1737          * is required when user only wants to check for uquery->prog_cnt.
1738          * There is no need to check for it since the case is handled
1739          * gracefully in bpf_prog_array_copy_info.
1740          */
1741
1742         mutex_lock(&bpf_event_mutex);
1743         progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
1744         ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
1745         mutex_unlock(&bpf_event_mutex);
1746
1747         if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
1748             copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
1749                 ret = -EFAULT;
1750
1751         kfree(ids);
1752         return ret;
1753 }
1754
1755 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
1756 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
1757
1758 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
1759 {
1760         struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
1761
1762         for (; btp < __stop__bpf_raw_tp; btp++) {
1763                 if (!strcmp(btp->tp->name, name))
1764                         return btp;
1765         }
1766
1767         return bpf_get_raw_tracepoint_module(name);
1768 }
1769
1770 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
1771 {
1772         struct module *mod = __module_address((unsigned long)btp);
1773
1774         if (mod)
1775                 module_put(mod);
1776 }
1777
1778 static __always_inline
1779 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
1780 {
1781         cant_sleep();
1782         rcu_read_lock();
1783         (void) BPF_PROG_RUN(prog, args);
1784         rcu_read_unlock();
1785 }
1786
1787 #define UNPACK(...)                     __VA_ARGS__
1788 #define REPEAT_1(FN, DL, X, ...)        FN(X)
1789 #define REPEAT_2(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
1790 #define REPEAT_3(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
1791 #define REPEAT_4(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
1792 #define REPEAT_5(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
1793 #define REPEAT_6(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
1794 #define REPEAT_7(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
1795 #define REPEAT_8(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
1796 #define REPEAT_9(FN, DL, X, ...)        FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
1797 #define REPEAT_10(FN, DL, X, ...)       FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
1798 #define REPEAT_11(FN, DL, X, ...)       FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
1799 #define REPEAT_12(FN, DL, X, ...)       FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
1800 #define REPEAT(X, FN, DL, ...)          REPEAT_##X(FN, DL, __VA_ARGS__)
1801
1802 #define SARG(X)         u64 arg##X
1803 #define COPY(X)         args[X] = arg##X
1804
1805 #define __DL_COM        (,)
1806 #define __DL_SEM        (;)
1807
1808 #define __SEQ_0_11      0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
1809
1810 #define BPF_TRACE_DEFN_x(x)                                             \
1811         void bpf_trace_run##x(struct bpf_prog *prog,                    \
1812                               REPEAT(x, SARG, __DL_COM, __SEQ_0_11))    \
1813         {                                                               \
1814                 u64 args[x];                                            \
1815                 REPEAT(x, COPY, __DL_SEM, __SEQ_0_11);                  \
1816                 __bpf_trace_run(prog, args);                            \
1817         }                                                               \
1818         EXPORT_SYMBOL_GPL(bpf_trace_run##x)
1819 BPF_TRACE_DEFN_x(1);
1820 BPF_TRACE_DEFN_x(2);
1821 BPF_TRACE_DEFN_x(3);
1822 BPF_TRACE_DEFN_x(4);
1823 BPF_TRACE_DEFN_x(5);
1824 BPF_TRACE_DEFN_x(6);
1825 BPF_TRACE_DEFN_x(7);
1826 BPF_TRACE_DEFN_x(8);
1827 BPF_TRACE_DEFN_x(9);
1828 BPF_TRACE_DEFN_x(10);
1829 BPF_TRACE_DEFN_x(11);
1830 BPF_TRACE_DEFN_x(12);
1831
1832 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1833 {
1834         struct tracepoint *tp = btp->tp;
1835
1836         /*
1837          * check that program doesn't access arguments beyond what's
1838          * available in this tracepoint
1839          */
1840         if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
1841                 return -EINVAL;
1842
1843         if (prog->aux->max_tp_access > btp->writable_size)
1844                 return -EINVAL;
1845
1846         return tracepoint_probe_register(tp, (void *)btp->bpf_func, prog);
1847 }
1848
1849 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1850 {
1851         return __bpf_probe_register(btp, prog);
1852 }
1853
1854 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1855 {
1856         return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
1857 }
1858
1859 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
1860                             u32 *fd_type, const char **buf,
1861                             u64 *probe_offset, u64 *probe_addr)
1862 {
1863         bool is_tracepoint, is_syscall_tp;
1864         struct bpf_prog *prog;
1865         int flags, err = 0;
1866
1867         prog = event->prog;
1868         if (!prog)
1869                 return -ENOENT;
1870
1871         /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
1872         if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
1873                 return -EOPNOTSUPP;
1874
1875         *prog_id = prog->aux->id;
1876         flags = event->tp_event->flags;
1877         is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
1878         is_syscall_tp = is_syscall_trace_event(event->tp_event);
1879
1880         if (is_tracepoint || is_syscall_tp) {
1881                 *buf = is_tracepoint ? event->tp_event->tp->name
1882                                      : event->tp_event->name;
1883                 *fd_type = BPF_FD_TYPE_TRACEPOINT;
1884                 *probe_offset = 0x0;
1885                 *probe_addr = 0x0;
1886         } else {
1887                 /* kprobe/uprobe */
1888                 err = -EOPNOTSUPP;
1889 #ifdef CONFIG_KPROBE_EVENTS
1890                 if (flags & TRACE_EVENT_FL_KPROBE)
1891                         err = bpf_get_kprobe_info(event, fd_type, buf,
1892                                                   probe_offset, probe_addr,
1893                                                   event->attr.type == PERF_TYPE_TRACEPOINT);
1894 #endif
1895 #ifdef CONFIG_UPROBE_EVENTS
1896                 if (flags & TRACE_EVENT_FL_UPROBE)
1897                         err = bpf_get_uprobe_info(event, fd_type, buf,
1898                                                   probe_offset,
1899                                                   event->attr.type == PERF_TYPE_TRACEPOINT);
1900 #endif
1901         }
1902
1903         return err;
1904 }
1905
1906 static int __init send_signal_irq_work_init(void)
1907 {
1908         int cpu;
1909         struct send_signal_irq_work *work;
1910
1911         for_each_possible_cpu(cpu) {
1912                 work = per_cpu_ptr(&send_signal_work, cpu);
1913                 init_irq_work(&work->irq_work, do_bpf_send_signal);
1914         }
1915         return 0;
1916 }
1917
1918 subsys_initcall(send_signal_irq_work_init);
1919
1920 #ifdef CONFIG_MODULES
1921 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
1922                             void *module)
1923 {
1924         struct bpf_trace_module *btm, *tmp;
1925         struct module *mod = module;
1926
1927         if (mod->num_bpf_raw_events == 0 ||
1928             (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
1929                 return 0;
1930
1931         mutex_lock(&bpf_module_mutex);
1932
1933         switch (op) {
1934         case MODULE_STATE_COMING:
1935                 btm = kzalloc(sizeof(*btm), GFP_KERNEL);
1936                 if (btm) {
1937                         btm->module = module;
1938                         list_add(&btm->list, &bpf_trace_modules);
1939                 }
1940                 break;
1941         case MODULE_STATE_GOING:
1942                 list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
1943                         if (btm->module == module) {
1944                                 list_del(&btm->list);
1945                                 kfree(btm);
1946                                 break;
1947                         }
1948                 }
1949                 break;
1950         }
1951
1952         mutex_unlock(&bpf_module_mutex);
1953
1954         return 0;
1955 }
1956
1957 static struct notifier_block bpf_module_nb = {
1958         .notifier_call = bpf_event_notify,
1959 };
1960
1961 static int __init bpf_event_init(void)
1962 {
1963         register_module_notifier(&bpf_module_nb);
1964         return 0;
1965 }
1966
1967 fs_initcall(bpf_event_init);
1968 #endif /* CONFIG_MODULES */