1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
3 * Copyright (c) 2016 Facebook
5 #include <linux/kernel.h>
6 #include <linux/types.h>
7 #include <linux/slab.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>
21 #include <net/bpf_sk_storage.h>
23 #include <uapi/linux/bpf.h>
24 #include <uapi/linux/btf.h>
28 #include "trace_probe.h"
31 #define CREATE_TRACE_POINTS
32 #include "bpf_trace.h"
34 #define bpf_event_rcu_dereference(p) \
35 rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
38 struct bpf_trace_module {
39 struct module *module;
40 struct list_head list;
43 static LIST_HEAD(bpf_trace_modules);
44 static DEFINE_MUTEX(bpf_module_mutex);
46 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
48 struct bpf_raw_event_map *btp, *ret = NULL;
49 struct bpf_trace_module *btm;
52 mutex_lock(&bpf_module_mutex);
53 list_for_each_entry(btm, &bpf_trace_modules, list) {
54 for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
55 btp = &btm->module->bpf_raw_events[i];
56 if (!strcmp(btp->tp->name, name)) {
57 if (try_module_get(btm->module))
64 mutex_unlock(&bpf_module_mutex);
68 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
72 #endif /* CONFIG_MODULES */
74 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
75 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
77 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
78 u64 flags, const struct btf **btf,
82 * trace_call_bpf - invoke BPF program
83 * @call: tracepoint event
84 * @ctx: opaque context pointer
86 * kprobe handlers execute BPF programs via this helper.
87 * Can be used from static tracepoints in the future.
89 * Return: BPF programs always return an integer which is interpreted by
91 * 0 - return from kprobe (event is filtered out)
92 * 1 - store kprobe event into ring buffer
93 * Other values are reserved and currently alias to 1
95 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
101 if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
103 * since some bpf program is already running on this cpu,
104 * don't call into another bpf program (same or different)
105 * and don't send kprobe event into ring-buffer,
106 * so return zero here
113 * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
114 * to all call sites, we did a bpf_prog_array_valid() there to check
115 * whether call->prog_array is empty or not, which is
116 * a heuristic to speed up execution.
118 * If bpf_prog_array_valid() fetched prog_array was
119 * non-NULL, we go into trace_call_bpf() and do the actual
120 * proper rcu_dereference() under RCU lock.
121 * If it turns out that prog_array is NULL then, we bail out.
122 * For the opposite, if the bpf_prog_array_valid() fetched pointer
123 * was NULL, you'll skip the prog_array with the risk of missing
124 * out of events when it was updated in between this and the
125 * rcu_dereference() which is accepted risk.
127 ret = BPF_PROG_RUN_ARRAY(call->prog_array, ctx, bpf_prog_run);
130 __this_cpu_dec(bpf_prog_active);
135 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
136 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
138 regs_set_return_value(regs, rc);
139 override_function_with_return(regs);
143 static const struct bpf_func_proto bpf_override_return_proto = {
144 .func = bpf_override_return,
146 .ret_type = RET_INTEGER,
147 .arg1_type = ARG_PTR_TO_CTX,
148 .arg2_type = ARG_ANYTHING,
152 static __always_inline int
153 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
157 ret = copy_from_user_nofault(dst, unsafe_ptr, size);
158 if (unlikely(ret < 0))
159 memset(dst, 0, size);
163 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
164 const void __user *, unsafe_ptr)
166 return bpf_probe_read_user_common(dst, size, unsafe_ptr);
169 const struct bpf_func_proto bpf_probe_read_user_proto = {
170 .func = bpf_probe_read_user,
172 .ret_type = RET_INTEGER,
173 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
174 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
175 .arg3_type = ARG_ANYTHING,
178 static __always_inline int
179 bpf_probe_read_user_str_common(void *dst, u32 size,
180 const void __user *unsafe_ptr)
185 * NB: We rely on strncpy_from_user() not copying junk past the NUL
186 * terminator into `dst`.
188 * strncpy_from_user() does long-sized strides in the fast path. If the
189 * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
190 * then there could be junk after the NUL in `dst`. If user takes `dst`
191 * and keys a hash map with it, then semantically identical strings can
192 * occupy multiple entries in the map.
194 ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
195 if (unlikely(ret < 0))
196 memset(dst, 0, size);
200 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
201 const void __user *, unsafe_ptr)
203 return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
206 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
207 .func = bpf_probe_read_user_str,
209 .ret_type = RET_INTEGER,
210 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
211 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
212 .arg3_type = ARG_ANYTHING,
215 static __always_inline int
216 bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
220 ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
221 if (unlikely(ret < 0))
222 memset(dst, 0, size);
226 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
227 const void *, unsafe_ptr)
229 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
232 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
233 .func = bpf_probe_read_kernel,
235 .ret_type = RET_INTEGER,
236 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
237 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
238 .arg3_type = ARG_ANYTHING,
241 static __always_inline int
242 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
247 * The strncpy_from_kernel_nofault() call will likely not fill the
248 * entire buffer, but that's okay in this circumstance as we're probing
249 * arbitrary memory anyway similar to bpf_probe_read_*() and might
250 * as well probe the stack. Thus, memory is explicitly cleared
251 * only in error case, so that improper users ignoring return
252 * code altogether don't copy garbage; otherwise length of string
253 * is returned that can be used for bpf_perf_event_output() et al.
255 ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
256 if (unlikely(ret < 0))
257 memset(dst, 0, size);
261 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
262 const void *, unsafe_ptr)
264 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
267 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
268 .func = bpf_probe_read_kernel_str,
270 .ret_type = RET_INTEGER,
271 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
272 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
273 .arg3_type = ARG_ANYTHING,
276 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
277 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
278 const void *, unsafe_ptr)
280 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
281 return bpf_probe_read_user_common(dst, size,
282 (__force void __user *)unsafe_ptr);
284 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
287 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
288 .func = bpf_probe_read_compat,
290 .ret_type = RET_INTEGER,
291 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
292 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
293 .arg3_type = ARG_ANYTHING,
296 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
297 const void *, unsafe_ptr)
299 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
300 return bpf_probe_read_user_str_common(dst, size,
301 (__force void __user *)unsafe_ptr);
303 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
306 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
307 .func = bpf_probe_read_compat_str,
309 .ret_type = RET_INTEGER,
310 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
311 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
312 .arg3_type = ARG_ANYTHING,
314 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
316 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
320 * Ensure we're in user context which is safe for the helper to
321 * run. This helper has no business in a kthread.
323 * access_ok() should prevent writing to non-user memory, but in
324 * some situations (nommu, temporary switch, etc) access_ok() does
325 * not provide enough validation, hence the check on KERNEL_DS.
327 * nmi_uaccess_okay() ensures the probe is not run in an interim
328 * state, when the task or mm are switched. This is specifically
329 * required to prevent the use of temporary mm.
332 if (unlikely(in_interrupt() ||
333 current->flags & (PF_KTHREAD | PF_EXITING)))
335 if (unlikely(uaccess_kernel()))
337 if (unlikely(!nmi_uaccess_okay()))
340 return copy_to_user_nofault(unsafe_ptr, src, size);
343 static const struct bpf_func_proto bpf_probe_write_user_proto = {
344 .func = bpf_probe_write_user,
346 .ret_type = RET_INTEGER,
347 .arg1_type = ARG_ANYTHING,
348 .arg2_type = ARG_PTR_TO_MEM,
349 .arg3_type = ARG_CONST_SIZE,
352 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
354 if (!capable(CAP_SYS_ADMIN))
357 pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
358 current->comm, task_pid_nr(current));
360 return &bpf_probe_write_user_proto;
363 static DEFINE_RAW_SPINLOCK(trace_printk_lock);
365 #define MAX_TRACE_PRINTK_VARARGS 3
366 #define BPF_TRACE_PRINTK_SIZE 1024
368 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
369 u64, arg2, u64, arg3)
371 u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
373 static char buf[BPF_TRACE_PRINTK_SIZE];
377 ret = bpf_bprintf_prepare(fmt, fmt_size, args, &bin_args,
378 MAX_TRACE_PRINTK_VARARGS);
382 raw_spin_lock_irqsave(&trace_printk_lock, flags);
383 ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
385 trace_bpf_trace_printk(buf);
386 raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
388 bpf_bprintf_cleanup();
393 static const struct bpf_func_proto bpf_trace_printk_proto = {
394 .func = bpf_trace_printk,
396 .ret_type = RET_INTEGER,
397 .arg1_type = ARG_PTR_TO_MEM,
398 .arg2_type = ARG_CONST_SIZE,
401 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
404 * This program might be calling bpf_trace_printk,
405 * so enable the associated bpf_trace/bpf_trace_printk event.
406 * Repeat this each time as it is possible a user has
407 * disabled bpf_trace_printk events. By loading a program
408 * calling bpf_trace_printk() however the user has expressed
409 * the intent to see such events.
411 if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
412 pr_warn_ratelimited("could not enable bpf_trace_printk events");
414 return &bpf_trace_printk_proto;
417 #define MAX_SEQ_PRINTF_VARARGS 12
419 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
420 const void *, data, u32, data_len)
425 if (data_len & 7 || data_len > MAX_SEQ_PRINTF_VARARGS * 8 ||
428 num_args = data_len / 8;
430 err = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
434 seq_bprintf(m, fmt, bin_args);
436 bpf_bprintf_cleanup();
438 return seq_has_overflowed(m) ? -EOVERFLOW : 0;
441 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
443 static const struct bpf_func_proto bpf_seq_printf_proto = {
444 .func = bpf_seq_printf,
446 .ret_type = RET_INTEGER,
447 .arg1_type = ARG_PTR_TO_BTF_ID,
448 .arg1_btf_id = &btf_seq_file_ids[0],
449 .arg2_type = ARG_PTR_TO_MEM,
450 .arg3_type = ARG_CONST_SIZE,
451 .arg4_type = ARG_PTR_TO_MEM_OR_NULL,
452 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
455 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
457 return seq_write(m, data, len) ? -EOVERFLOW : 0;
460 static const struct bpf_func_proto bpf_seq_write_proto = {
461 .func = bpf_seq_write,
463 .ret_type = RET_INTEGER,
464 .arg1_type = ARG_PTR_TO_BTF_ID,
465 .arg1_btf_id = &btf_seq_file_ids[0],
466 .arg2_type = ARG_PTR_TO_MEM,
467 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
470 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
471 u32, btf_ptr_size, u64, flags)
473 const struct btf *btf;
477 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
481 return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
484 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
485 .func = bpf_seq_printf_btf,
487 .ret_type = RET_INTEGER,
488 .arg1_type = ARG_PTR_TO_BTF_ID,
489 .arg1_btf_id = &btf_seq_file_ids[0],
490 .arg2_type = ARG_PTR_TO_MEM,
491 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
492 .arg4_type = ARG_ANYTHING,
495 static __always_inline int
496 get_map_perf_counter(struct bpf_map *map, u64 flags,
497 u64 *value, u64 *enabled, u64 *running)
499 struct bpf_array *array = container_of(map, struct bpf_array, map);
500 unsigned int cpu = smp_processor_id();
501 u64 index = flags & BPF_F_INDEX_MASK;
502 struct bpf_event_entry *ee;
504 if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
506 if (index == BPF_F_CURRENT_CPU)
508 if (unlikely(index >= array->map.max_entries))
511 ee = READ_ONCE(array->ptrs[index]);
515 return perf_event_read_local(ee->event, value, enabled, running);
518 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
523 err = get_map_perf_counter(map, flags, &value, NULL, NULL);
525 * this api is ugly since we miss [-22..-2] range of valid
526 * counter values, but that's uapi
533 static const struct bpf_func_proto bpf_perf_event_read_proto = {
534 .func = bpf_perf_event_read,
536 .ret_type = RET_INTEGER,
537 .arg1_type = ARG_CONST_MAP_PTR,
538 .arg2_type = ARG_ANYTHING,
541 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
542 struct bpf_perf_event_value *, buf, u32, size)
546 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
548 err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
554 memset(buf, 0, size);
558 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
559 .func = bpf_perf_event_read_value,
561 .ret_type = RET_INTEGER,
562 .arg1_type = ARG_CONST_MAP_PTR,
563 .arg2_type = ARG_ANYTHING,
564 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
565 .arg4_type = ARG_CONST_SIZE,
568 static __always_inline u64
569 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
570 u64 flags, struct perf_sample_data *sd)
572 struct bpf_array *array = container_of(map, struct bpf_array, map);
573 unsigned int cpu = smp_processor_id();
574 u64 index = flags & BPF_F_INDEX_MASK;
575 struct bpf_event_entry *ee;
576 struct perf_event *event;
578 if (index == BPF_F_CURRENT_CPU)
580 if (unlikely(index >= array->map.max_entries))
583 ee = READ_ONCE(array->ptrs[index]);
588 if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
589 event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
592 if (unlikely(event->oncpu != cpu))
595 return perf_event_output(event, sd, regs);
599 * Support executing tracepoints in normal, irq, and nmi context that each call
600 * bpf_perf_event_output
602 struct bpf_trace_sample_data {
603 struct perf_sample_data sds[3];
606 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
607 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
608 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
609 u64, flags, void *, data, u64, size)
611 struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds);
612 int nest_level = this_cpu_inc_return(bpf_trace_nest_level);
613 struct perf_raw_record raw = {
619 struct perf_sample_data *sd;
622 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
627 sd = &sds->sds[nest_level - 1];
629 if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
634 perf_sample_data_init(sd, 0, 0);
637 err = __bpf_perf_event_output(regs, map, flags, sd);
640 this_cpu_dec(bpf_trace_nest_level);
644 static const struct bpf_func_proto bpf_perf_event_output_proto = {
645 .func = bpf_perf_event_output,
647 .ret_type = RET_INTEGER,
648 .arg1_type = ARG_PTR_TO_CTX,
649 .arg2_type = ARG_CONST_MAP_PTR,
650 .arg3_type = ARG_ANYTHING,
651 .arg4_type = ARG_PTR_TO_MEM,
652 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
655 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
656 struct bpf_nested_pt_regs {
657 struct pt_regs regs[3];
659 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
660 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
662 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
663 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
665 int nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
666 struct perf_raw_frag frag = {
671 struct perf_raw_record raw = {
674 .next = ctx_size ? &frag : NULL,
680 struct perf_sample_data *sd;
681 struct pt_regs *regs;
684 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
688 sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
689 regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
691 perf_fetch_caller_regs(regs);
692 perf_sample_data_init(sd, 0, 0);
695 ret = __bpf_perf_event_output(regs, map, flags, sd);
697 this_cpu_dec(bpf_event_output_nest_level);
701 BPF_CALL_0(bpf_get_current_task)
703 return (long) current;
706 const struct bpf_func_proto bpf_get_current_task_proto = {
707 .func = bpf_get_current_task,
709 .ret_type = RET_INTEGER,
712 BPF_CALL_0(bpf_get_current_task_btf)
714 return (unsigned long) current;
717 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
718 .func = bpf_get_current_task_btf,
720 .ret_type = RET_PTR_TO_BTF_ID,
721 .ret_btf_id = &btf_task_struct_ids[0],
724 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
726 return (unsigned long) task_pt_regs(task);
729 BTF_ID_LIST(bpf_task_pt_regs_ids)
730 BTF_ID(struct, pt_regs)
732 const struct bpf_func_proto bpf_task_pt_regs_proto = {
733 .func = bpf_task_pt_regs,
735 .arg1_type = ARG_PTR_TO_BTF_ID,
736 .arg1_btf_id = &btf_task_struct_ids[0],
737 .ret_type = RET_PTR_TO_BTF_ID,
738 .ret_btf_id = &bpf_task_pt_regs_ids[0],
741 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
743 struct bpf_array *array = container_of(map, struct bpf_array, map);
746 if (unlikely(idx >= array->map.max_entries))
749 cgrp = READ_ONCE(array->ptrs[idx]);
753 return task_under_cgroup_hierarchy(current, cgrp);
756 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
757 .func = bpf_current_task_under_cgroup,
759 .ret_type = RET_INTEGER,
760 .arg1_type = ARG_CONST_MAP_PTR,
761 .arg2_type = ARG_ANYTHING,
764 struct send_signal_irq_work {
765 struct irq_work irq_work;
766 struct task_struct *task;
771 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
773 static void do_bpf_send_signal(struct irq_work *entry)
775 struct send_signal_irq_work *work;
777 work = container_of(entry, struct send_signal_irq_work, irq_work);
778 group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
781 static int bpf_send_signal_common(u32 sig, enum pid_type type)
783 struct send_signal_irq_work *work = NULL;
785 /* Similar to bpf_probe_write_user, task needs to be
786 * in a sound condition and kernel memory access be
787 * permitted in order to send signal to the current
790 if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
792 if (unlikely(uaccess_kernel()))
794 if (unlikely(!nmi_uaccess_okay()))
797 if (irqs_disabled()) {
798 /* Do an early check on signal validity. Otherwise,
799 * the error is lost in deferred irq_work.
801 if (unlikely(!valid_signal(sig)))
804 work = this_cpu_ptr(&send_signal_work);
805 if (irq_work_is_busy(&work->irq_work))
808 /* Add the current task, which is the target of sending signal,
809 * to the irq_work. The current task may change when queued
810 * irq works get executed.
812 work->task = current;
815 irq_work_queue(&work->irq_work);
819 return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
822 BPF_CALL_1(bpf_send_signal, u32, sig)
824 return bpf_send_signal_common(sig, PIDTYPE_TGID);
827 static const struct bpf_func_proto bpf_send_signal_proto = {
828 .func = bpf_send_signal,
830 .ret_type = RET_INTEGER,
831 .arg1_type = ARG_ANYTHING,
834 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
836 return bpf_send_signal_common(sig, PIDTYPE_PID);
839 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
840 .func = bpf_send_signal_thread,
842 .ret_type = RET_INTEGER,
843 .arg1_type = ARG_ANYTHING,
846 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
854 p = d_path(path, buf, sz);
859 memmove(buf, p, len);
865 BTF_SET_START(btf_allowlist_d_path)
866 #ifdef CONFIG_SECURITY
867 BTF_ID(func, security_file_permission)
868 BTF_ID(func, security_inode_getattr)
869 BTF_ID(func, security_file_open)
871 #ifdef CONFIG_SECURITY_PATH
872 BTF_ID(func, security_path_truncate)
874 BTF_ID(func, vfs_truncate)
875 BTF_ID(func, vfs_fallocate)
876 BTF_ID(func, dentry_open)
877 BTF_ID(func, vfs_getattr)
878 BTF_ID(func, filp_close)
879 BTF_SET_END(btf_allowlist_d_path)
881 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
883 if (prog->type == BPF_PROG_TYPE_TRACING &&
884 prog->expected_attach_type == BPF_TRACE_ITER)
887 if (prog->type == BPF_PROG_TYPE_LSM)
888 return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
890 return btf_id_set_contains(&btf_allowlist_d_path,
891 prog->aux->attach_btf_id);
894 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
896 static const struct bpf_func_proto bpf_d_path_proto = {
899 .ret_type = RET_INTEGER,
900 .arg1_type = ARG_PTR_TO_BTF_ID,
901 .arg1_btf_id = &bpf_d_path_btf_ids[0],
902 .arg2_type = ARG_PTR_TO_MEM,
903 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
904 .allowed = bpf_d_path_allowed,
907 #define BTF_F_ALL (BTF_F_COMPACT | BTF_F_NONAME | \
908 BTF_F_PTR_RAW | BTF_F_ZERO)
910 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
911 u64 flags, const struct btf **btf,
914 const struct btf_type *t;
916 if (unlikely(flags & ~(BTF_F_ALL)))
919 if (btf_ptr_size != sizeof(struct btf_ptr))
922 *btf = bpf_get_btf_vmlinux();
924 if (IS_ERR_OR_NULL(*btf))
925 return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
927 if (ptr->type_id > 0)
928 *btf_id = ptr->type_id;
933 t = btf_type_by_id(*btf, *btf_id);
934 if (*btf_id <= 0 || !t)
940 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
941 u32, btf_ptr_size, u64, flags)
943 const struct btf *btf;
947 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
951 return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
955 const struct bpf_func_proto bpf_snprintf_btf_proto = {
956 .func = bpf_snprintf_btf,
958 .ret_type = RET_INTEGER,
959 .arg1_type = ARG_PTR_TO_MEM,
960 .arg2_type = ARG_CONST_SIZE,
961 .arg3_type = ARG_PTR_TO_MEM,
962 .arg4_type = ARG_CONST_SIZE,
963 .arg5_type = ARG_ANYTHING,
966 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
968 /* This helper call is inlined by verifier. */
969 return ((u64 *)ctx)[-1];
972 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
973 .func = bpf_get_func_ip_tracing,
975 .ret_type = RET_INTEGER,
976 .arg1_type = ARG_PTR_TO_CTX,
979 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
981 struct kprobe *kp = kprobe_running();
983 return kp ? (uintptr_t)kp->addr : 0;
986 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
987 .func = bpf_get_func_ip_kprobe,
989 .ret_type = RET_INTEGER,
990 .arg1_type = ARG_PTR_TO_CTX,
993 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
995 struct bpf_trace_run_ctx *run_ctx;
997 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
998 return run_ctx->bpf_cookie;
1001 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
1002 .func = bpf_get_attach_cookie_trace,
1004 .ret_type = RET_INTEGER,
1005 .arg1_type = ARG_PTR_TO_CTX,
1008 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
1010 return ctx->event->bpf_cookie;
1013 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
1014 .func = bpf_get_attach_cookie_pe,
1016 .ret_type = RET_INTEGER,
1017 .arg1_type = ARG_PTR_TO_CTX,
1020 static const struct bpf_func_proto *
1021 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1024 case BPF_FUNC_map_lookup_elem:
1025 return &bpf_map_lookup_elem_proto;
1026 case BPF_FUNC_map_update_elem:
1027 return &bpf_map_update_elem_proto;
1028 case BPF_FUNC_map_delete_elem:
1029 return &bpf_map_delete_elem_proto;
1030 case BPF_FUNC_map_push_elem:
1031 return &bpf_map_push_elem_proto;
1032 case BPF_FUNC_map_pop_elem:
1033 return &bpf_map_pop_elem_proto;
1034 case BPF_FUNC_map_peek_elem:
1035 return &bpf_map_peek_elem_proto;
1036 case BPF_FUNC_ktime_get_ns:
1037 return &bpf_ktime_get_ns_proto;
1038 case BPF_FUNC_ktime_get_boot_ns:
1039 return &bpf_ktime_get_boot_ns_proto;
1040 case BPF_FUNC_ktime_get_coarse_ns:
1041 return &bpf_ktime_get_coarse_ns_proto;
1042 case BPF_FUNC_tail_call:
1043 return &bpf_tail_call_proto;
1044 case BPF_FUNC_get_current_pid_tgid:
1045 return &bpf_get_current_pid_tgid_proto;
1046 case BPF_FUNC_get_current_task:
1047 return &bpf_get_current_task_proto;
1048 case BPF_FUNC_get_current_task_btf:
1049 return &bpf_get_current_task_btf_proto;
1050 case BPF_FUNC_task_pt_regs:
1051 return &bpf_task_pt_regs_proto;
1052 case BPF_FUNC_get_current_uid_gid:
1053 return &bpf_get_current_uid_gid_proto;
1054 case BPF_FUNC_get_current_comm:
1055 return &bpf_get_current_comm_proto;
1056 case BPF_FUNC_trace_printk:
1057 return bpf_get_trace_printk_proto();
1058 case BPF_FUNC_get_smp_processor_id:
1059 return &bpf_get_smp_processor_id_proto;
1060 case BPF_FUNC_get_numa_node_id:
1061 return &bpf_get_numa_node_id_proto;
1062 case BPF_FUNC_perf_event_read:
1063 return &bpf_perf_event_read_proto;
1064 case BPF_FUNC_current_task_under_cgroup:
1065 return &bpf_current_task_under_cgroup_proto;
1066 case BPF_FUNC_get_prandom_u32:
1067 return &bpf_get_prandom_u32_proto;
1068 case BPF_FUNC_probe_write_user:
1069 return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
1070 NULL : bpf_get_probe_write_proto();
1071 case BPF_FUNC_probe_read_user:
1072 return &bpf_probe_read_user_proto;
1073 case BPF_FUNC_probe_read_kernel:
1074 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1075 NULL : &bpf_probe_read_kernel_proto;
1076 case BPF_FUNC_probe_read_user_str:
1077 return &bpf_probe_read_user_str_proto;
1078 case BPF_FUNC_probe_read_kernel_str:
1079 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1080 NULL : &bpf_probe_read_kernel_str_proto;
1081 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1082 case BPF_FUNC_probe_read:
1083 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1084 NULL : &bpf_probe_read_compat_proto;
1085 case BPF_FUNC_probe_read_str:
1086 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1087 NULL : &bpf_probe_read_compat_str_proto;
1089 #ifdef CONFIG_CGROUPS
1090 case BPF_FUNC_get_current_cgroup_id:
1091 return &bpf_get_current_cgroup_id_proto;
1092 case BPF_FUNC_get_current_ancestor_cgroup_id:
1093 return &bpf_get_current_ancestor_cgroup_id_proto;
1095 case BPF_FUNC_send_signal:
1096 return &bpf_send_signal_proto;
1097 case BPF_FUNC_send_signal_thread:
1098 return &bpf_send_signal_thread_proto;
1099 case BPF_FUNC_perf_event_read_value:
1100 return &bpf_perf_event_read_value_proto;
1101 case BPF_FUNC_get_ns_current_pid_tgid:
1102 return &bpf_get_ns_current_pid_tgid_proto;
1103 case BPF_FUNC_ringbuf_output:
1104 return &bpf_ringbuf_output_proto;
1105 case BPF_FUNC_ringbuf_reserve:
1106 return &bpf_ringbuf_reserve_proto;
1107 case BPF_FUNC_ringbuf_submit:
1108 return &bpf_ringbuf_submit_proto;
1109 case BPF_FUNC_ringbuf_discard:
1110 return &bpf_ringbuf_discard_proto;
1111 case BPF_FUNC_ringbuf_query:
1112 return &bpf_ringbuf_query_proto;
1113 case BPF_FUNC_jiffies64:
1114 return &bpf_jiffies64_proto;
1115 case BPF_FUNC_get_task_stack:
1116 return &bpf_get_task_stack_proto;
1117 case BPF_FUNC_copy_from_user:
1118 return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
1119 case BPF_FUNC_snprintf_btf:
1120 return &bpf_snprintf_btf_proto;
1121 case BPF_FUNC_per_cpu_ptr:
1122 return &bpf_per_cpu_ptr_proto;
1123 case BPF_FUNC_this_cpu_ptr:
1124 return &bpf_this_cpu_ptr_proto;
1125 case BPF_FUNC_task_storage_get:
1126 return &bpf_task_storage_get_proto;
1127 case BPF_FUNC_task_storage_delete:
1128 return &bpf_task_storage_delete_proto;
1129 case BPF_FUNC_for_each_map_elem:
1130 return &bpf_for_each_map_elem_proto;
1131 case BPF_FUNC_snprintf:
1132 return &bpf_snprintf_proto;
1133 case BPF_FUNC_get_func_ip:
1134 return &bpf_get_func_ip_proto_tracing;
1136 return bpf_base_func_proto(func_id);
1140 static const struct bpf_func_proto *
1141 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1144 case BPF_FUNC_perf_event_output:
1145 return &bpf_perf_event_output_proto;
1146 case BPF_FUNC_get_stackid:
1147 return &bpf_get_stackid_proto;
1148 case BPF_FUNC_get_stack:
1149 return &bpf_get_stack_proto;
1150 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1151 case BPF_FUNC_override_return:
1152 return &bpf_override_return_proto;
1154 case BPF_FUNC_get_func_ip:
1155 return &bpf_get_func_ip_proto_kprobe;
1156 case BPF_FUNC_get_attach_cookie:
1157 return &bpf_get_attach_cookie_proto_trace;
1159 return bpf_tracing_func_proto(func_id, prog);
1163 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
1164 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1165 const struct bpf_prog *prog,
1166 struct bpf_insn_access_aux *info)
1168 if (off < 0 || off >= sizeof(struct pt_regs))
1170 if (type != BPF_READ)
1172 if (off % size != 0)
1175 * Assertion for 32 bit to make sure last 8 byte access
1176 * (BPF_DW) to the last 4 byte member is disallowed.
1178 if (off + size > sizeof(struct pt_regs))
1184 const struct bpf_verifier_ops kprobe_verifier_ops = {
1185 .get_func_proto = kprobe_prog_func_proto,
1186 .is_valid_access = kprobe_prog_is_valid_access,
1189 const struct bpf_prog_ops kprobe_prog_ops = {
1192 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1193 u64, flags, void *, data, u64, size)
1195 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1198 * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1199 * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1200 * from there and call the same bpf_perf_event_output() helper inline.
1202 return ____bpf_perf_event_output(regs, map, flags, data, size);
1205 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1206 .func = bpf_perf_event_output_tp,
1208 .ret_type = RET_INTEGER,
1209 .arg1_type = ARG_PTR_TO_CTX,
1210 .arg2_type = ARG_CONST_MAP_PTR,
1211 .arg3_type = ARG_ANYTHING,
1212 .arg4_type = ARG_PTR_TO_MEM,
1213 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1216 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1219 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1222 * Same comment as in bpf_perf_event_output_tp(), only that this time
1223 * the other helper's function body cannot be inlined due to being
1224 * external, thus we need to call raw helper function.
1226 return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1230 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1231 .func = bpf_get_stackid_tp,
1233 .ret_type = RET_INTEGER,
1234 .arg1_type = ARG_PTR_TO_CTX,
1235 .arg2_type = ARG_CONST_MAP_PTR,
1236 .arg3_type = ARG_ANYTHING,
1239 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1242 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1244 return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1245 (unsigned long) size, flags, 0);
1248 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1249 .func = bpf_get_stack_tp,
1251 .ret_type = RET_INTEGER,
1252 .arg1_type = ARG_PTR_TO_CTX,
1253 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1254 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1255 .arg4_type = ARG_ANYTHING,
1258 static const struct bpf_func_proto *
1259 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1262 case BPF_FUNC_perf_event_output:
1263 return &bpf_perf_event_output_proto_tp;
1264 case BPF_FUNC_get_stackid:
1265 return &bpf_get_stackid_proto_tp;
1266 case BPF_FUNC_get_stack:
1267 return &bpf_get_stack_proto_tp;
1268 case BPF_FUNC_get_attach_cookie:
1269 return &bpf_get_attach_cookie_proto_trace;
1271 return bpf_tracing_func_proto(func_id, prog);
1275 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1276 const struct bpf_prog *prog,
1277 struct bpf_insn_access_aux *info)
1279 if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1281 if (type != BPF_READ)
1283 if (off % size != 0)
1286 BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1290 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1291 .get_func_proto = tp_prog_func_proto,
1292 .is_valid_access = tp_prog_is_valid_access,
1295 const struct bpf_prog_ops tracepoint_prog_ops = {
1298 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1299 struct bpf_perf_event_value *, buf, u32, size)
1303 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1305 err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1311 memset(buf, 0, size);
1315 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1316 .func = bpf_perf_prog_read_value,
1318 .ret_type = RET_INTEGER,
1319 .arg1_type = ARG_PTR_TO_CTX,
1320 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1321 .arg3_type = ARG_CONST_SIZE,
1324 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1325 void *, buf, u32, size, u64, flags)
1330 static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1331 struct perf_branch_stack *br_stack = ctx->data->br_stack;
1334 if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1337 if (unlikely(!br_stack))
1340 if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1341 return br_stack->nr * br_entry_size;
1343 if (!buf || (size % br_entry_size != 0))
1346 to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1347 memcpy(buf, br_stack->entries, to_copy);
1353 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1354 .func = bpf_read_branch_records,
1356 .ret_type = RET_INTEGER,
1357 .arg1_type = ARG_PTR_TO_CTX,
1358 .arg2_type = ARG_PTR_TO_MEM_OR_NULL,
1359 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1360 .arg4_type = ARG_ANYTHING,
1363 static const struct bpf_func_proto *
1364 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1367 case BPF_FUNC_perf_event_output:
1368 return &bpf_perf_event_output_proto_tp;
1369 case BPF_FUNC_get_stackid:
1370 return &bpf_get_stackid_proto_pe;
1371 case BPF_FUNC_get_stack:
1372 return &bpf_get_stack_proto_pe;
1373 case BPF_FUNC_perf_prog_read_value:
1374 return &bpf_perf_prog_read_value_proto;
1375 case BPF_FUNC_read_branch_records:
1376 return &bpf_read_branch_records_proto;
1377 case BPF_FUNC_get_attach_cookie:
1378 return &bpf_get_attach_cookie_proto_pe;
1380 return bpf_tracing_func_proto(func_id, prog);
1385 * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1386 * to avoid potential recursive reuse issue when/if tracepoints are added
1387 * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1389 * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1390 * in normal, irq, and nmi context.
1392 struct bpf_raw_tp_regs {
1393 struct pt_regs regs[3];
1395 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1396 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
1397 static struct pt_regs *get_bpf_raw_tp_regs(void)
1399 struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1400 int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1402 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1403 this_cpu_dec(bpf_raw_tp_nest_level);
1404 return ERR_PTR(-EBUSY);
1407 return &tp_regs->regs[nest_level - 1];
1410 static void put_bpf_raw_tp_regs(void)
1412 this_cpu_dec(bpf_raw_tp_nest_level);
1415 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1416 struct bpf_map *, map, u64, flags, void *, data, u64, size)
1418 struct pt_regs *regs = get_bpf_raw_tp_regs();
1422 return PTR_ERR(regs);
1424 perf_fetch_caller_regs(regs);
1425 ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1427 put_bpf_raw_tp_regs();
1431 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1432 .func = bpf_perf_event_output_raw_tp,
1434 .ret_type = RET_INTEGER,
1435 .arg1_type = ARG_PTR_TO_CTX,
1436 .arg2_type = ARG_CONST_MAP_PTR,
1437 .arg3_type = ARG_ANYTHING,
1438 .arg4_type = ARG_PTR_TO_MEM,
1439 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1442 extern const struct bpf_func_proto bpf_skb_output_proto;
1443 extern const struct bpf_func_proto bpf_xdp_output_proto;
1445 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1446 struct bpf_map *, map, u64, flags)
1448 struct pt_regs *regs = get_bpf_raw_tp_regs();
1452 return PTR_ERR(regs);
1454 perf_fetch_caller_regs(regs);
1455 /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1456 ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1458 put_bpf_raw_tp_regs();
1462 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1463 .func = bpf_get_stackid_raw_tp,
1465 .ret_type = RET_INTEGER,
1466 .arg1_type = ARG_PTR_TO_CTX,
1467 .arg2_type = ARG_CONST_MAP_PTR,
1468 .arg3_type = ARG_ANYTHING,
1471 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1472 void *, buf, u32, size, u64, flags)
1474 struct pt_regs *regs = get_bpf_raw_tp_regs();
1478 return PTR_ERR(regs);
1480 perf_fetch_caller_regs(regs);
1481 ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1482 (unsigned long) size, flags, 0);
1483 put_bpf_raw_tp_regs();
1487 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1488 .func = bpf_get_stack_raw_tp,
1490 .ret_type = RET_INTEGER,
1491 .arg1_type = ARG_PTR_TO_CTX,
1492 .arg2_type = ARG_PTR_TO_MEM,
1493 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1494 .arg4_type = ARG_ANYTHING,
1497 static const struct bpf_func_proto *
1498 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1501 case BPF_FUNC_perf_event_output:
1502 return &bpf_perf_event_output_proto_raw_tp;
1503 case BPF_FUNC_get_stackid:
1504 return &bpf_get_stackid_proto_raw_tp;
1505 case BPF_FUNC_get_stack:
1506 return &bpf_get_stack_proto_raw_tp;
1508 return bpf_tracing_func_proto(func_id, prog);
1512 const struct bpf_func_proto *
1513 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1515 const struct bpf_func_proto *fn;
1519 case BPF_FUNC_skb_output:
1520 return &bpf_skb_output_proto;
1521 case BPF_FUNC_xdp_output:
1522 return &bpf_xdp_output_proto;
1523 case BPF_FUNC_skc_to_tcp6_sock:
1524 return &bpf_skc_to_tcp6_sock_proto;
1525 case BPF_FUNC_skc_to_tcp_sock:
1526 return &bpf_skc_to_tcp_sock_proto;
1527 case BPF_FUNC_skc_to_tcp_timewait_sock:
1528 return &bpf_skc_to_tcp_timewait_sock_proto;
1529 case BPF_FUNC_skc_to_tcp_request_sock:
1530 return &bpf_skc_to_tcp_request_sock_proto;
1531 case BPF_FUNC_skc_to_udp6_sock:
1532 return &bpf_skc_to_udp6_sock_proto;
1533 case BPF_FUNC_sk_storage_get:
1534 return &bpf_sk_storage_get_tracing_proto;
1535 case BPF_FUNC_sk_storage_delete:
1536 return &bpf_sk_storage_delete_tracing_proto;
1537 case BPF_FUNC_sock_from_file:
1538 return &bpf_sock_from_file_proto;
1539 case BPF_FUNC_get_socket_cookie:
1540 return &bpf_get_socket_ptr_cookie_proto;
1542 case BPF_FUNC_seq_printf:
1543 return prog->expected_attach_type == BPF_TRACE_ITER ?
1544 &bpf_seq_printf_proto :
1546 case BPF_FUNC_seq_write:
1547 return prog->expected_attach_type == BPF_TRACE_ITER ?
1548 &bpf_seq_write_proto :
1550 case BPF_FUNC_seq_printf_btf:
1551 return prog->expected_attach_type == BPF_TRACE_ITER ?
1552 &bpf_seq_printf_btf_proto :
1554 case BPF_FUNC_d_path:
1555 return &bpf_d_path_proto;
1557 fn = raw_tp_prog_func_proto(func_id, prog);
1558 if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
1559 fn = bpf_iter_get_func_proto(func_id, prog);
1564 static bool raw_tp_prog_is_valid_access(int off, int size,
1565 enum bpf_access_type type,
1566 const struct bpf_prog *prog,
1567 struct bpf_insn_access_aux *info)
1569 if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
1571 if (type != BPF_READ)
1573 if (off % size != 0)
1578 static bool tracing_prog_is_valid_access(int off, int size,
1579 enum bpf_access_type type,
1580 const struct bpf_prog *prog,
1581 struct bpf_insn_access_aux *info)
1583 if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
1585 if (type != BPF_READ)
1587 if (off % size != 0)
1589 return btf_ctx_access(off, size, type, prog, info);
1592 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
1593 const union bpf_attr *kattr,
1594 union bpf_attr __user *uattr)
1599 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
1600 .get_func_proto = raw_tp_prog_func_proto,
1601 .is_valid_access = raw_tp_prog_is_valid_access,
1604 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
1606 .test_run = bpf_prog_test_run_raw_tp,
1610 const struct bpf_verifier_ops tracing_verifier_ops = {
1611 .get_func_proto = tracing_prog_func_proto,
1612 .is_valid_access = tracing_prog_is_valid_access,
1615 const struct bpf_prog_ops tracing_prog_ops = {
1616 .test_run = bpf_prog_test_run_tracing,
1619 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
1620 enum bpf_access_type type,
1621 const struct bpf_prog *prog,
1622 struct bpf_insn_access_aux *info)
1625 if (size != sizeof(u64) || type != BPF_READ)
1627 info->reg_type = PTR_TO_TP_BUFFER;
1629 return raw_tp_prog_is_valid_access(off, size, type, prog, info);
1632 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
1633 .get_func_proto = raw_tp_prog_func_proto,
1634 .is_valid_access = raw_tp_writable_prog_is_valid_access,
1637 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
1640 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1641 const struct bpf_prog *prog,
1642 struct bpf_insn_access_aux *info)
1644 const int size_u64 = sizeof(u64);
1646 if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
1648 if (type != BPF_READ)
1650 if (off % size != 0) {
1651 if (sizeof(unsigned long) != 4)
1655 if (off % size != 4)
1660 case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
1661 bpf_ctx_record_field_size(info, size_u64);
1662 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1665 case bpf_ctx_range(struct bpf_perf_event_data, addr):
1666 bpf_ctx_record_field_size(info, size_u64);
1667 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1671 if (size != sizeof(long))
1678 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
1679 const struct bpf_insn *si,
1680 struct bpf_insn *insn_buf,
1681 struct bpf_prog *prog, u32 *target_size)
1683 struct bpf_insn *insn = insn_buf;
1686 case offsetof(struct bpf_perf_event_data, sample_period):
1687 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1688 data), si->dst_reg, si->src_reg,
1689 offsetof(struct bpf_perf_event_data_kern, data));
1690 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1691 bpf_target_off(struct perf_sample_data, period, 8,
1694 case offsetof(struct bpf_perf_event_data, addr):
1695 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1696 data), si->dst_reg, si->src_reg,
1697 offsetof(struct bpf_perf_event_data_kern, data));
1698 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1699 bpf_target_off(struct perf_sample_data, addr, 8,
1703 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1704 regs), si->dst_reg, si->src_reg,
1705 offsetof(struct bpf_perf_event_data_kern, regs));
1706 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
1711 return insn - insn_buf;
1714 const struct bpf_verifier_ops perf_event_verifier_ops = {
1715 .get_func_proto = pe_prog_func_proto,
1716 .is_valid_access = pe_prog_is_valid_access,
1717 .convert_ctx_access = pe_prog_convert_ctx_access,
1720 const struct bpf_prog_ops perf_event_prog_ops = {
1723 static DEFINE_MUTEX(bpf_event_mutex);
1725 #define BPF_TRACE_MAX_PROGS 64
1727 int perf_event_attach_bpf_prog(struct perf_event *event,
1728 struct bpf_prog *prog,
1731 struct bpf_prog_array *old_array;
1732 struct bpf_prog_array *new_array;
1736 * Kprobe override only works if they are on the function entry,
1737 * and only if they are on the opt-in list.
1739 if (prog->kprobe_override &&
1740 (!trace_kprobe_on_func_entry(event->tp_event) ||
1741 !trace_kprobe_error_injectable(event->tp_event)))
1744 mutex_lock(&bpf_event_mutex);
1749 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1751 bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
1756 ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
1760 /* set the new array to event->tp_event and set event->prog */
1762 event->bpf_cookie = bpf_cookie;
1763 rcu_assign_pointer(event->tp_event->prog_array, new_array);
1764 bpf_prog_array_free(old_array);
1767 mutex_unlock(&bpf_event_mutex);
1771 void perf_event_detach_bpf_prog(struct perf_event *event)
1773 struct bpf_prog_array *old_array;
1774 struct bpf_prog_array *new_array;
1777 mutex_lock(&bpf_event_mutex);
1782 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1783 ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
1787 bpf_prog_array_delete_safe(old_array, event->prog);
1789 rcu_assign_pointer(event->tp_event->prog_array, new_array);
1790 bpf_prog_array_free(old_array);
1793 bpf_prog_put(event->prog);
1797 mutex_unlock(&bpf_event_mutex);
1800 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
1802 struct perf_event_query_bpf __user *uquery = info;
1803 struct perf_event_query_bpf query = {};
1804 struct bpf_prog_array *progs;
1805 u32 *ids, prog_cnt, ids_len;
1808 if (!perfmon_capable())
1810 if (event->attr.type != PERF_TYPE_TRACEPOINT)
1812 if (copy_from_user(&query, uquery, sizeof(query)))
1815 ids_len = query.ids_len;
1816 if (ids_len > BPF_TRACE_MAX_PROGS)
1818 ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
1822 * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
1823 * is required when user only wants to check for uquery->prog_cnt.
1824 * There is no need to check for it since the case is handled
1825 * gracefully in bpf_prog_array_copy_info.
1828 mutex_lock(&bpf_event_mutex);
1829 progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
1830 ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
1831 mutex_unlock(&bpf_event_mutex);
1833 if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
1834 copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
1841 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
1842 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
1844 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
1846 struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
1848 for (; btp < __stop__bpf_raw_tp; btp++) {
1849 if (!strcmp(btp->tp->name, name))
1853 return bpf_get_raw_tracepoint_module(name);
1856 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
1861 mod = __module_address((unsigned long)btp);
1866 static __always_inline
1867 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
1871 (void) bpf_prog_run(prog, args);
1875 #define UNPACK(...) __VA_ARGS__
1876 #define REPEAT_1(FN, DL, X, ...) FN(X)
1877 #define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
1878 #define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
1879 #define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
1880 #define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
1881 #define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
1882 #define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
1883 #define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
1884 #define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
1885 #define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
1886 #define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
1887 #define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
1888 #define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
1890 #define SARG(X) u64 arg##X
1891 #define COPY(X) args[X] = arg##X
1893 #define __DL_COM (,)
1894 #define __DL_SEM (;)
1896 #define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
1898 #define BPF_TRACE_DEFN_x(x) \
1899 void bpf_trace_run##x(struct bpf_prog *prog, \
1900 REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
1903 REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
1904 __bpf_trace_run(prog, args); \
1906 EXPORT_SYMBOL_GPL(bpf_trace_run##x)
1907 BPF_TRACE_DEFN_x(1);
1908 BPF_TRACE_DEFN_x(2);
1909 BPF_TRACE_DEFN_x(3);
1910 BPF_TRACE_DEFN_x(4);
1911 BPF_TRACE_DEFN_x(5);
1912 BPF_TRACE_DEFN_x(6);
1913 BPF_TRACE_DEFN_x(7);
1914 BPF_TRACE_DEFN_x(8);
1915 BPF_TRACE_DEFN_x(9);
1916 BPF_TRACE_DEFN_x(10);
1917 BPF_TRACE_DEFN_x(11);
1918 BPF_TRACE_DEFN_x(12);
1920 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1922 struct tracepoint *tp = btp->tp;
1925 * check that program doesn't access arguments beyond what's
1926 * available in this tracepoint
1928 if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
1931 if (prog->aux->max_tp_access > btp->writable_size)
1934 return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
1938 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1940 return __bpf_probe_register(btp, prog);
1943 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
1945 return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
1948 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
1949 u32 *fd_type, const char **buf,
1950 u64 *probe_offset, u64 *probe_addr)
1952 bool is_tracepoint, is_syscall_tp;
1953 struct bpf_prog *prog;
1960 /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
1961 if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
1964 *prog_id = prog->aux->id;
1965 flags = event->tp_event->flags;
1966 is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
1967 is_syscall_tp = is_syscall_trace_event(event->tp_event);
1969 if (is_tracepoint || is_syscall_tp) {
1970 *buf = is_tracepoint ? event->tp_event->tp->name
1971 : event->tp_event->name;
1972 *fd_type = BPF_FD_TYPE_TRACEPOINT;
1973 *probe_offset = 0x0;
1978 #ifdef CONFIG_KPROBE_EVENTS
1979 if (flags & TRACE_EVENT_FL_KPROBE)
1980 err = bpf_get_kprobe_info(event, fd_type, buf,
1981 probe_offset, probe_addr,
1982 event->attr.type == PERF_TYPE_TRACEPOINT);
1984 #ifdef CONFIG_UPROBE_EVENTS
1985 if (flags & TRACE_EVENT_FL_UPROBE)
1986 err = bpf_get_uprobe_info(event, fd_type, buf,
1988 event->attr.type == PERF_TYPE_TRACEPOINT);
1995 static int __init send_signal_irq_work_init(void)
1998 struct send_signal_irq_work *work;
2000 for_each_possible_cpu(cpu) {
2001 work = per_cpu_ptr(&send_signal_work, cpu);
2002 init_irq_work(&work->irq_work, do_bpf_send_signal);
2007 subsys_initcall(send_signal_irq_work_init);
2009 #ifdef CONFIG_MODULES
2010 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
2013 struct bpf_trace_module *btm, *tmp;
2014 struct module *mod = module;
2017 if (mod->num_bpf_raw_events == 0 ||
2018 (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
2021 mutex_lock(&bpf_module_mutex);
2024 case MODULE_STATE_COMING:
2025 btm = kzalloc(sizeof(*btm), GFP_KERNEL);
2027 btm->module = module;
2028 list_add(&btm->list, &bpf_trace_modules);
2033 case MODULE_STATE_GOING:
2034 list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
2035 if (btm->module == module) {
2036 list_del(&btm->list);
2044 mutex_unlock(&bpf_module_mutex);
2047 return notifier_from_errno(ret);
2050 static struct notifier_block bpf_module_nb = {
2051 .notifier_call = bpf_event_notify,
2054 static int __init bpf_event_init(void)
2056 register_module_notifier(&bpf_module_nb);
2060 fs_initcall(bpf_event_init);
2061 #endif /* CONFIG_MODULES */