drm/connector: hdmi: Fix memory leak in drm_display_mode_from_cea_vic()
[drm/drm-misc.git] / kernel / trace / bpf_trace.c
blob3bd402fa62a400bcd0298fb29cddfb662d0ccfa9
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_verifier.h>
10 #include <linux/bpf_perf_event.h>
11 #include <linux/btf.h>
12 #include <linux/filter.h>
13 #include <linux/uaccess.h>
14 #include <linux/ctype.h>
15 #include <linux/kprobes.h>
16 #include <linux/spinlock.h>
17 #include <linux/syscalls.h>
18 #include <linux/error-injection.h>
19 #include <linux/btf_ids.h>
20 #include <linux/bpf_lsm.h>
21 #include <linux/fprobe.h>
22 #include <linux/bsearch.h>
23 #include <linux/sort.h>
24 #include <linux/key.h>
25 #include <linux/verification.h>
26 #include <linux/namei.h>
28 #include <net/bpf_sk_storage.h>
30 #include <uapi/linux/bpf.h>
31 #include <uapi/linux/btf.h>
33 #include <asm/tlb.h>
35 #include "trace_probe.h"
36 #include "trace.h"
38 #define CREATE_TRACE_POINTS
39 #include "bpf_trace.h"
41 #define bpf_event_rcu_dereference(p) \
42 rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
44 #define MAX_UPROBE_MULTI_CNT (1U << 20)
45 #define MAX_KPROBE_MULTI_CNT (1U << 20)
47 #ifdef CONFIG_MODULES
48 struct bpf_trace_module {
49 struct module *module;
50 struct list_head list;
53 static LIST_HEAD(bpf_trace_modules);
54 static DEFINE_MUTEX(bpf_module_mutex);
56 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
58 struct bpf_raw_event_map *btp, *ret = NULL;
59 struct bpf_trace_module *btm;
60 unsigned int i;
62 mutex_lock(&bpf_module_mutex);
63 list_for_each_entry(btm, &bpf_trace_modules, list) {
64 for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
65 btp = &btm->module->bpf_raw_events[i];
66 if (!strcmp(btp->tp->name, name)) {
67 if (try_module_get(btm->module))
68 ret = btp;
69 goto out;
73 out:
74 mutex_unlock(&bpf_module_mutex);
75 return ret;
77 #else
78 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
80 return NULL;
82 #endif /* CONFIG_MODULES */
84 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
85 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
87 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
88 u64 flags, const struct btf **btf,
89 s32 *btf_id);
90 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
91 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
93 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx);
94 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
96 /**
97 * trace_call_bpf - invoke BPF program
98 * @call: tracepoint event
99 * @ctx: opaque context pointer
101 * kprobe handlers execute BPF programs via this helper.
102 * Can be used from static tracepoints in the future.
104 * Return: BPF programs always return an integer which is interpreted by
105 * kprobe handler as:
106 * 0 - return from kprobe (event is filtered out)
107 * 1 - store kprobe event into ring buffer
108 * Other values are reserved and currently alias to 1
110 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
112 unsigned int ret;
114 cant_sleep();
116 if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
118 * since some bpf program is already running on this cpu,
119 * don't call into another bpf program (same or different)
120 * and don't send kprobe event into ring-buffer,
121 * so return zero here
123 rcu_read_lock();
124 bpf_prog_inc_misses_counters(rcu_dereference(call->prog_array));
125 rcu_read_unlock();
126 ret = 0;
127 goto out;
131 * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
132 * to all call sites, we did a bpf_prog_array_valid() there to check
133 * whether call->prog_array is empty or not, which is
134 * a heuristic to speed up execution.
136 * If bpf_prog_array_valid() fetched prog_array was
137 * non-NULL, we go into trace_call_bpf() and do the actual
138 * proper rcu_dereference() under RCU lock.
139 * If it turns out that prog_array is NULL then, we bail out.
140 * For the opposite, if the bpf_prog_array_valid() fetched pointer
141 * was NULL, you'll skip the prog_array with the risk of missing
142 * out of events when it was updated in between this and the
143 * rcu_dereference() which is accepted risk.
145 rcu_read_lock();
146 ret = bpf_prog_run_array(rcu_dereference(call->prog_array),
147 ctx, bpf_prog_run);
148 rcu_read_unlock();
150 out:
151 __this_cpu_dec(bpf_prog_active);
153 return ret;
156 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
157 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
159 regs_set_return_value(regs, rc);
160 override_function_with_return(regs);
161 return 0;
164 static const struct bpf_func_proto bpf_override_return_proto = {
165 .func = bpf_override_return,
166 .gpl_only = true,
167 .ret_type = RET_INTEGER,
168 .arg1_type = ARG_PTR_TO_CTX,
169 .arg2_type = ARG_ANYTHING,
171 #endif
173 static __always_inline int
174 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
176 int ret;
178 ret = copy_from_user_nofault(dst, unsafe_ptr, size);
179 if (unlikely(ret < 0))
180 memset(dst, 0, size);
181 return ret;
184 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
185 const void __user *, unsafe_ptr)
187 return bpf_probe_read_user_common(dst, size, unsafe_ptr);
190 const struct bpf_func_proto bpf_probe_read_user_proto = {
191 .func = bpf_probe_read_user,
192 .gpl_only = true,
193 .ret_type = RET_INTEGER,
194 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
195 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
196 .arg3_type = ARG_ANYTHING,
199 static __always_inline int
200 bpf_probe_read_user_str_common(void *dst, u32 size,
201 const void __user *unsafe_ptr)
203 int ret;
206 * NB: We rely on strncpy_from_user() not copying junk past the NUL
207 * terminator into `dst`.
209 * strncpy_from_user() does long-sized strides in the fast path. If the
210 * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
211 * then there could be junk after the NUL in `dst`. If user takes `dst`
212 * and keys a hash map with it, then semantically identical strings can
213 * occupy multiple entries in the map.
215 ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
216 if (unlikely(ret < 0))
217 memset(dst, 0, size);
218 return ret;
221 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
222 const void __user *, unsafe_ptr)
224 return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
227 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
228 .func = bpf_probe_read_user_str,
229 .gpl_only = true,
230 .ret_type = RET_INTEGER,
231 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
232 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
233 .arg3_type = ARG_ANYTHING,
236 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
237 const void *, unsafe_ptr)
239 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
242 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
243 .func = bpf_probe_read_kernel,
244 .gpl_only = true,
245 .ret_type = RET_INTEGER,
246 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
247 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
248 .arg3_type = ARG_ANYTHING,
251 static __always_inline int
252 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
254 int ret;
257 * The strncpy_from_kernel_nofault() call will likely not fill the
258 * entire buffer, but that's okay in this circumstance as we're probing
259 * arbitrary memory anyway similar to bpf_probe_read_*() and might
260 * as well probe the stack. Thus, memory is explicitly cleared
261 * only in error case, so that improper users ignoring return
262 * code altogether don't copy garbage; otherwise length of string
263 * is returned that can be used for bpf_perf_event_output() et al.
265 ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
266 if (unlikely(ret < 0))
267 memset(dst, 0, size);
268 return ret;
271 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
272 const void *, unsafe_ptr)
274 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
277 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
278 .func = bpf_probe_read_kernel_str,
279 .gpl_only = true,
280 .ret_type = RET_INTEGER,
281 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
282 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
283 .arg3_type = ARG_ANYTHING,
286 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
287 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
288 const void *, unsafe_ptr)
290 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
291 return bpf_probe_read_user_common(dst, size,
292 (__force void __user *)unsafe_ptr);
294 return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
297 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
298 .func = bpf_probe_read_compat,
299 .gpl_only = true,
300 .ret_type = RET_INTEGER,
301 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
302 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
303 .arg3_type = ARG_ANYTHING,
306 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
307 const void *, unsafe_ptr)
309 if ((unsigned long)unsafe_ptr < TASK_SIZE) {
310 return bpf_probe_read_user_str_common(dst, size,
311 (__force void __user *)unsafe_ptr);
313 return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
316 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
317 .func = bpf_probe_read_compat_str,
318 .gpl_only = true,
319 .ret_type = RET_INTEGER,
320 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
321 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
322 .arg3_type = ARG_ANYTHING,
324 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
326 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
327 u32, size)
330 * Ensure we're in user context which is safe for the helper to
331 * run. This helper has no business in a kthread.
333 * access_ok() should prevent writing to non-user memory, but in
334 * some situations (nommu, temporary switch, etc) access_ok() does
335 * not provide enough validation, hence the check on KERNEL_DS.
337 * nmi_uaccess_okay() ensures the probe is not run in an interim
338 * state, when the task or mm are switched. This is specifically
339 * required to prevent the use of temporary mm.
342 if (unlikely(in_interrupt() ||
343 current->flags & (PF_KTHREAD | PF_EXITING)))
344 return -EPERM;
345 if (unlikely(!nmi_uaccess_okay()))
346 return -EPERM;
348 return copy_to_user_nofault(unsafe_ptr, src, size);
351 static const struct bpf_func_proto bpf_probe_write_user_proto = {
352 .func = bpf_probe_write_user,
353 .gpl_only = true,
354 .ret_type = RET_INTEGER,
355 .arg1_type = ARG_ANYTHING,
356 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
357 .arg3_type = ARG_CONST_SIZE,
360 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
362 if (!capable(CAP_SYS_ADMIN))
363 return NULL;
365 pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
366 current->comm, task_pid_nr(current));
368 return &bpf_probe_write_user_proto;
371 #define MAX_TRACE_PRINTK_VARARGS 3
372 #define BPF_TRACE_PRINTK_SIZE 1024
374 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
375 u64, arg2, u64, arg3)
377 u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
378 struct bpf_bprintf_data data = {
379 .get_bin_args = true,
380 .get_buf = true,
382 int ret;
384 ret = bpf_bprintf_prepare(fmt, fmt_size, args,
385 MAX_TRACE_PRINTK_VARARGS, &data);
386 if (ret < 0)
387 return ret;
389 ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
391 trace_bpf_trace_printk(data.buf);
393 bpf_bprintf_cleanup(&data);
395 return ret;
398 static const struct bpf_func_proto bpf_trace_printk_proto = {
399 .func = bpf_trace_printk,
400 .gpl_only = true,
401 .ret_type = RET_INTEGER,
402 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY,
403 .arg2_type = ARG_CONST_SIZE,
406 static void __set_printk_clr_event(void)
409 * This program might be calling bpf_trace_printk,
410 * so enable the associated bpf_trace/bpf_trace_printk event.
411 * Repeat this each time as it is possible a user has
412 * disabled bpf_trace_printk events. By loading a program
413 * calling bpf_trace_printk() however the user has expressed
414 * the intent to see such events.
416 if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
417 pr_warn_ratelimited("could not enable bpf_trace_printk events");
420 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
422 __set_printk_clr_event();
423 return &bpf_trace_printk_proto;
426 BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, args,
427 u32, data_len)
429 struct bpf_bprintf_data data = {
430 .get_bin_args = true,
431 .get_buf = true,
433 int ret, num_args;
435 if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
436 (data_len && !args))
437 return -EINVAL;
438 num_args = data_len / 8;
440 ret = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
441 if (ret < 0)
442 return ret;
444 ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
446 trace_bpf_trace_printk(data.buf);
448 bpf_bprintf_cleanup(&data);
450 return ret;
453 static const struct bpf_func_proto bpf_trace_vprintk_proto = {
454 .func = bpf_trace_vprintk,
455 .gpl_only = true,
456 .ret_type = RET_INTEGER,
457 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY,
458 .arg2_type = ARG_CONST_SIZE,
459 .arg3_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
460 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
463 const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
465 __set_printk_clr_event();
466 return &bpf_trace_vprintk_proto;
469 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
470 const void *, args, u32, data_len)
472 struct bpf_bprintf_data data = {
473 .get_bin_args = true,
475 int err, num_args;
477 if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
478 (data_len && !args))
479 return -EINVAL;
480 num_args = data_len / 8;
482 err = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
483 if (err < 0)
484 return err;
486 seq_bprintf(m, fmt, data.bin_args);
488 bpf_bprintf_cleanup(&data);
490 return seq_has_overflowed(m) ? -EOVERFLOW : 0;
493 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
495 static const struct bpf_func_proto bpf_seq_printf_proto = {
496 .func = bpf_seq_printf,
497 .gpl_only = true,
498 .ret_type = RET_INTEGER,
499 .arg1_type = ARG_PTR_TO_BTF_ID,
500 .arg1_btf_id = &btf_seq_file_ids[0],
501 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
502 .arg3_type = ARG_CONST_SIZE,
503 .arg4_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
504 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
507 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
509 return seq_write(m, data, len) ? -EOVERFLOW : 0;
512 static const struct bpf_func_proto bpf_seq_write_proto = {
513 .func = bpf_seq_write,
514 .gpl_only = true,
515 .ret_type = RET_INTEGER,
516 .arg1_type = ARG_PTR_TO_BTF_ID,
517 .arg1_btf_id = &btf_seq_file_ids[0],
518 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
519 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
522 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
523 u32, btf_ptr_size, u64, flags)
525 const struct btf *btf;
526 s32 btf_id;
527 int ret;
529 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
530 if (ret)
531 return ret;
533 return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
536 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
537 .func = bpf_seq_printf_btf,
538 .gpl_only = true,
539 .ret_type = RET_INTEGER,
540 .arg1_type = ARG_PTR_TO_BTF_ID,
541 .arg1_btf_id = &btf_seq_file_ids[0],
542 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
543 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
544 .arg4_type = ARG_ANYTHING,
547 static __always_inline int
548 get_map_perf_counter(struct bpf_map *map, u64 flags,
549 u64 *value, u64 *enabled, u64 *running)
551 struct bpf_array *array = container_of(map, struct bpf_array, map);
552 unsigned int cpu = smp_processor_id();
553 u64 index = flags & BPF_F_INDEX_MASK;
554 struct bpf_event_entry *ee;
556 if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
557 return -EINVAL;
558 if (index == BPF_F_CURRENT_CPU)
559 index = cpu;
560 if (unlikely(index >= array->map.max_entries))
561 return -E2BIG;
563 ee = READ_ONCE(array->ptrs[index]);
564 if (!ee)
565 return -ENOENT;
567 return perf_event_read_local(ee->event, value, enabled, running);
570 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
572 u64 value = 0;
573 int err;
575 err = get_map_perf_counter(map, flags, &value, NULL, NULL);
577 * this api is ugly since we miss [-22..-2] range of valid
578 * counter values, but that's uapi
580 if (err)
581 return err;
582 return value;
585 static const struct bpf_func_proto bpf_perf_event_read_proto = {
586 .func = bpf_perf_event_read,
587 .gpl_only = true,
588 .ret_type = RET_INTEGER,
589 .arg1_type = ARG_CONST_MAP_PTR,
590 .arg2_type = ARG_ANYTHING,
593 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
594 struct bpf_perf_event_value *, buf, u32, size)
596 int err = -EINVAL;
598 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
599 goto clear;
600 err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
601 &buf->running);
602 if (unlikely(err))
603 goto clear;
604 return 0;
605 clear:
606 memset(buf, 0, size);
607 return err;
610 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
611 .func = bpf_perf_event_read_value,
612 .gpl_only = true,
613 .ret_type = RET_INTEGER,
614 .arg1_type = ARG_CONST_MAP_PTR,
615 .arg2_type = ARG_ANYTHING,
616 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
617 .arg4_type = ARG_CONST_SIZE,
620 static __always_inline u64
621 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
622 u64 flags, struct perf_sample_data *sd)
624 struct bpf_array *array = container_of(map, struct bpf_array, map);
625 unsigned int cpu = smp_processor_id();
626 u64 index = flags & BPF_F_INDEX_MASK;
627 struct bpf_event_entry *ee;
628 struct perf_event *event;
630 if (index == BPF_F_CURRENT_CPU)
631 index = cpu;
632 if (unlikely(index >= array->map.max_entries))
633 return -E2BIG;
635 ee = READ_ONCE(array->ptrs[index]);
636 if (!ee)
637 return -ENOENT;
639 event = ee->event;
640 if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
641 event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
642 return -EINVAL;
644 if (unlikely(event->oncpu != cpu))
645 return -EOPNOTSUPP;
647 return perf_event_output(event, sd, regs);
651 * Support executing tracepoints in normal, irq, and nmi context that each call
652 * bpf_perf_event_output
654 struct bpf_trace_sample_data {
655 struct perf_sample_data sds[3];
658 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
659 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
660 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
661 u64, flags, void *, data, u64, size)
663 struct bpf_trace_sample_data *sds;
664 struct perf_raw_record raw = {
665 .frag = {
666 .size = size,
667 .data = data,
670 struct perf_sample_data *sd;
671 int nest_level, err;
673 preempt_disable();
674 sds = this_cpu_ptr(&bpf_trace_sds);
675 nest_level = this_cpu_inc_return(bpf_trace_nest_level);
677 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
678 err = -EBUSY;
679 goto out;
682 sd = &sds->sds[nest_level - 1];
684 if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
685 err = -EINVAL;
686 goto out;
689 perf_sample_data_init(sd, 0, 0);
690 perf_sample_save_raw_data(sd, &raw);
692 err = __bpf_perf_event_output(regs, map, flags, sd);
693 out:
694 this_cpu_dec(bpf_trace_nest_level);
695 preempt_enable();
696 return err;
699 static const struct bpf_func_proto bpf_perf_event_output_proto = {
700 .func = bpf_perf_event_output,
701 .gpl_only = true,
702 .ret_type = RET_INTEGER,
703 .arg1_type = ARG_PTR_TO_CTX,
704 .arg2_type = ARG_CONST_MAP_PTR,
705 .arg3_type = ARG_ANYTHING,
706 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
707 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
710 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
711 struct bpf_nested_pt_regs {
712 struct pt_regs regs[3];
714 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
715 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
717 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
718 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
720 struct perf_raw_frag frag = {
721 .copy = ctx_copy,
722 .size = ctx_size,
723 .data = ctx,
725 struct perf_raw_record raw = {
726 .frag = {
728 .next = ctx_size ? &frag : NULL,
730 .size = meta_size,
731 .data = meta,
734 struct perf_sample_data *sd;
735 struct pt_regs *regs;
736 int nest_level;
737 u64 ret;
739 preempt_disable();
740 nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
742 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
743 ret = -EBUSY;
744 goto out;
746 sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
747 regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
749 perf_fetch_caller_regs(regs);
750 perf_sample_data_init(sd, 0, 0);
751 perf_sample_save_raw_data(sd, &raw);
753 ret = __bpf_perf_event_output(regs, map, flags, sd);
754 out:
755 this_cpu_dec(bpf_event_output_nest_level);
756 preempt_enable();
757 return ret;
760 BPF_CALL_0(bpf_get_current_task)
762 return (long) current;
765 const struct bpf_func_proto bpf_get_current_task_proto = {
766 .func = bpf_get_current_task,
767 .gpl_only = true,
768 .ret_type = RET_INTEGER,
771 BPF_CALL_0(bpf_get_current_task_btf)
773 return (unsigned long) current;
776 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
777 .func = bpf_get_current_task_btf,
778 .gpl_only = true,
779 .ret_type = RET_PTR_TO_BTF_ID_TRUSTED,
780 .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
783 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
785 return (unsigned long) task_pt_regs(task);
788 BTF_ID_LIST(bpf_task_pt_regs_ids)
789 BTF_ID(struct, pt_regs)
791 const struct bpf_func_proto bpf_task_pt_regs_proto = {
792 .func = bpf_task_pt_regs,
793 .gpl_only = true,
794 .arg1_type = ARG_PTR_TO_BTF_ID,
795 .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
796 .ret_type = RET_PTR_TO_BTF_ID,
797 .ret_btf_id = &bpf_task_pt_regs_ids[0],
800 struct send_signal_irq_work {
801 struct irq_work irq_work;
802 struct task_struct *task;
803 u32 sig;
804 enum pid_type type;
807 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
809 static void do_bpf_send_signal(struct irq_work *entry)
811 struct send_signal_irq_work *work;
813 work = container_of(entry, struct send_signal_irq_work, irq_work);
814 group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
815 put_task_struct(work->task);
818 static int bpf_send_signal_common(u32 sig, enum pid_type type)
820 struct send_signal_irq_work *work = NULL;
822 /* Similar to bpf_probe_write_user, task needs to be
823 * in a sound condition and kernel memory access be
824 * permitted in order to send signal to the current
825 * task.
827 if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
828 return -EPERM;
829 if (unlikely(!nmi_uaccess_okay()))
830 return -EPERM;
831 /* Task should not be pid=1 to avoid kernel panic. */
832 if (unlikely(is_global_init(current)))
833 return -EPERM;
835 if (irqs_disabled()) {
836 /* Do an early check on signal validity. Otherwise,
837 * the error is lost in deferred irq_work.
839 if (unlikely(!valid_signal(sig)))
840 return -EINVAL;
842 work = this_cpu_ptr(&send_signal_work);
843 if (irq_work_is_busy(&work->irq_work))
844 return -EBUSY;
846 /* Add the current task, which is the target of sending signal,
847 * to the irq_work. The current task may change when queued
848 * irq works get executed.
850 work->task = get_task_struct(current);
851 work->sig = sig;
852 work->type = type;
853 irq_work_queue(&work->irq_work);
854 return 0;
857 return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
860 BPF_CALL_1(bpf_send_signal, u32, sig)
862 return bpf_send_signal_common(sig, PIDTYPE_TGID);
865 static const struct bpf_func_proto bpf_send_signal_proto = {
866 .func = bpf_send_signal,
867 .gpl_only = false,
868 .ret_type = RET_INTEGER,
869 .arg1_type = ARG_ANYTHING,
872 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
874 return bpf_send_signal_common(sig, PIDTYPE_PID);
877 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
878 .func = bpf_send_signal_thread,
879 .gpl_only = false,
880 .ret_type = RET_INTEGER,
881 .arg1_type = ARG_ANYTHING,
884 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
886 struct path copy;
887 long len;
888 char *p;
890 if (!sz)
891 return 0;
894 * The path pointer is verified as trusted and safe to use,
895 * but let's double check it's valid anyway to workaround
896 * potentially broken verifier.
898 len = copy_from_kernel_nofault(&copy, path, sizeof(*path));
899 if (len < 0)
900 return len;
902 p = d_path(&copy, buf, sz);
903 if (IS_ERR(p)) {
904 len = PTR_ERR(p);
905 } else {
906 len = buf + sz - p;
907 memmove(buf, p, len);
910 return len;
913 BTF_SET_START(btf_allowlist_d_path)
914 #ifdef CONFIG_SECURITY
915 BTF_ID(func, security_file_permission)
916 BTF_ID(func, security_inode_getattr)
917 BTF_ID(func, security_file_open)
918 #endif
919 #ifdef CONFIG_SECURITY_PATH
920 BTF_ID(func, security_path_truncate)
921 #endif
922 BTF_ID(func, vfs_truncate)
923 BTF_ID(func, vfs_fallocate)
924 BTF_ID(func, dentry_open)
925 BTF_ID(func, vfs_getattr)
926 BTF_ID(func, filp_close)
927 BTF_SET_END(btf_allowlist_d_path)
929 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
931 if (prog->type == BPF_PROG_TYPE_TRACING &&
932 prog->expected_attach_type == BPF_TRACE_ITER)
933 return true;
935 if (prog->type == BPF_PROG_TYPE_LSM)
936 return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
938 return btf_id_set_contains(&btf_allowlist_d_path,
939 prog->aux->attach_btf_id);
942 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
944 static const struct bpf_func_proto bpf_d_path_proto = {
945 .func = bpf_d_path,
946 .gpl_only = false,
947 .ret_type = RET_INTEGER,
948 .arg1_type = ARG_PTR_TO_BTF_ID,
949 .arg1_btf_id = &bpf_d_path_btf_ids[0],
950 .arg2_type = ARG_PTR_TO_MEM,
951 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
952 .allowed = bpf_d_path_allowed,
955 #define BTF_F_ALL (BTF_F_COMPACT | BTF_F_NONAME | \
956 BTF_F_PTR_RAW | BTF_F_ZERO)
958 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
959 u64 flags, const struct btf **btf,
960 s32 *btf_id)
962 const struct btf_type *t;
964 if (unlikely(flags & ~(BTF_F_ALL)))
965 return -EINVAL;
967 if (btf_ptr_size != sizeof(struct btf_ptr))
968 return -EINVAL;
970 *btf = bpf_get_btf_vmlinux();
972 if (IS_ERR_OR_NULL(*btf))
973 return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
975 if (ptr->type_id > 0)
976 *btf_id = ptr->type_id;
977 else
978 return -EINVAL;
980 if (*btf_id > 0)
981 t = btf_type_by_id(*btf, *btf_id);
982 if (*btf_id <= 0 || !t)
983 return -ENOENT;
985 return 0;
988 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
989 u32, btf_ptr_size, u64, flags)
991 const struct btf *btf;
992 s32 btf_id;
993 int ret;
995 ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
996 if (ret)
997 return ret;
999 return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
1000 flags);
1003 const struct bpf_func_proto bpf_snprintf_btf_proto = {
1004 .func = bpf_snprintf_btf,
1005 .gpl_only = false,
1006 .ret_type = RET_INTEGER,
1007 .arg1_type = ARG_PTR_TO_MEM,
1008 .arg2_type = ARG_CONST_SIZE,
1009 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1010 .arg4_type = ARG_CONST_SIZE,
1011 .arg5_type = ARG_ANYTHING,
1014 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
1016 /* This helper call is inlined by verifier. */
1017 return ((u64 *)ctx)[-2];
1020 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
1021 .func = bpf_get_func_ip_tracing,
1022 .gpl_only = true,
1023 .ret_type = RET_INTEGER,
1024 .arg1_type = ARG_PTR_TO_CTX,
1027 #ifdef CONFIG_X86_KERNEL_IBT
1028 static unsigned long get_entry_ip(unsigned long fentry_ip)
1030 u32 instr;
1032 /* We want to be extra safe in case entry ip is on the page edge,
1033 * but otherwise we need to avoid get_kernel_nofault()'s overhead.
1035 if ((fentry_ip & ~PAGE_MASK) < ENDBR_INSN_SIZE) {
1036 if (get_kernel_nofault(instr, (u32 *)(fentry_ip - ENDBR_INSN_SIZE)))
1037 return fentry_ip;
1038 } else {
1039 instr = *(u32 *)(fentry_ip - ENDBR_INSN_SIZE);
1041 if (is_endbr(instr))
1042 fentry_ip -= ENDBR_INSN_SIZE;
1043 return fentry_ip;
1045 #else
1046 #define get_entry_ip(fentry_ip) fentry_ip
1047 #endif
1049 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
1051 struct bpf_trace_run_ctx *run_ctx __maybe_unused;
1052 struct kprobe *kp;
1054 #ifdef CONFIG_UPROBES
1055 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1056 if (run_ctx->is_uprobe)
1057 return ((struct uprobe_dispatch_data *)current->utask->vaddr)->bp_addr;
1058 #endif
1060 kp = kprobe_running();
1062 if (!kp || !(kp->flags & KPROBE_FLAG_ON_FUNC_ENTRY))
1063 return 0;
1065 return get_entry_ip((uintptr_t)kp->addr);
1068 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
1069 .func = bpf_get_func_ip_kprobe,
1070 .gpl_only = true,
1071 .ret_type = RET_INTEGER,
1072 .arg1_type = ARG_PTR_TO_CTX,
1075 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
1077 return bpf_kprobe_multi_entry_ip(current->bpf_ctx);
1080 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
1081 .func = bpf_get_func_ip_kprobe_multi,
1082 .gpl_only = false,
1083 .ret_type = RET_INTEGER,
1084 .arg1_type = ARG_PTR_TO_CTX,
1087 BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs)
1089 return bpf_kprobe_multi_cookie(current->bpf_ctx);
1092 static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
1093 .func = bpf_get_attach_cookie_kprobe_multi,
1094 .gpl_only = false,
1095 .ret_type = RET_INTEGER,
1096 .arg1_type = ARG_PTR_TO_CTX,
1099 BPF_CALL_1(bpf_get_func_ip_uprobe_multi, struct pt_regs *, regs)
1101 return bpf_uprobe_multi_entry_ip(current->bpf_ctx);
1104 static const struct bpf_func_proto bpf_get_func_ip_proto_uprobe_multi = {
1105 .func = bpf_get_func_ip_uprobe_multi,
1106 .gpl_only = false,
1107 .ret_type = RET_INTEGER,
1108 .arg1_type = ARG_PTR_TO_CTX,
1111 BPF_CALL_1(bpf_get_attach_cookie_uprobe_multi, struct pt_regs *, regs)
1113 return bpf_uprobe_multi_cookie(current->bpf_ctx);
1116 static const struct bpf_func_proto bpf_get_attach_cookie_proto_umulti = {
1117 .func = bpf_get_attach_cookie_uprobe_multi,
1118 .gpl_only = false,
1119 .ret_type = RET_INTEGER,
1120 .arg1_type = ARG_PTR_TO_CTX,
1123 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
1125 struct bpf_trace_run_ctx *run_ctx;
1127 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1128 return run_ctx->bpf_cookie;
1131 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
1132 .func = bpf_get_attach_cookie_trace,
1133 .gpl_only = false,
1134 .ret_type = RET_INTEGER,
1135 .arg1_type = ARG_PTR_TO_CTX,
1138 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
1140 return ctx->event->bpf_cookie;
1143 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
1144 .func = bpf_get_attach_cookie_pe,
1145 .gpl_only = false,
1146 .ret_type = RET_INTEGER,
1147 .arg1_type = ARG_PTR_TO_CTX,
1150 BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx)
1152 struct bpf_trace_run_ctx *run_ctx;
1154 run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1155 return run_ctx->bpf_cookie;
1158 static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = {
1159 .func = bpf_get_attach_cookie_tracing,
1160 .gpl_only = false,
1161 .ret_type = RET_INTEGER,
1162 .arg1_type = ARG_PTR_TO_CTX,
1165 BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
1167 static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1168 u32 entry_cnt = size / br_entry_size;
1170 entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
1172 if (unlikely(flags))
1173 return -EINVAL;
1175 if (!entry_cnt)
1176 return -ENOENT;
1178 return entry_cnt * br_entry_size;
1181 static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
1182 .func = bpf_get_branch_snapshot,
1183 .gpl_only = true,
1184 .ret_type = RET_INTEGER,
1185 .arg1_type = ARG_PTR_TO_UNINIT_MEM,
1186 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
1189 BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
1191 /* This helper call is inlined by verifier. */
1192 u64 nr_args = ((u64 *)ctx)[-1];
1194 if ((u64) n >= nr_args)
1195 return -EINVAL;
1196 *value = ((u64 *)ctx)[n];
1197 return 0;
1200 static const struct bpf_func_proto bpf_get_func_arg_proto = {
1201 .func = get_func_arg,
1202 .ret_type = RET_INTEGER,
1203 .arg1_type = ARG_PTR_TO_CTX,
1204 .arg2_type = ARG_ANYTHING,
1205 .arg3_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED,
1206 .arg3_size = sizeof(u64),
1209 BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
1211 /* This helper call is inlined by verifier. */
1212 u64 nr_args = ((u64 *)ctx)[-1];
1214 *value = ((u64 *)ctx)[nr_args];
1215 return 0;
1218 static const struct bpf_func_proto bpf_get_func_ret_proto = {
1219 .func = get_func_ret,
1220 .ret_type = RET_INTEGER,
1221 .arg1_type = ARG_PTR_TO_CTX,
1222 .arg2_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED,
1223 .arg2_size = sizeof(u64),
1226 BPF_CALL_1(get_func_arg_cnt, void *, ctx)
1228 /* This helper call is inlined by verifier. */
1229 return ((u64 *)ctx)[-1];
1232 static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
1233 .func = get_func_arg_cnt,
1234 .ret_type = RET_INTEGER,
1235 .arg1_type = ARG_PTR_TO_CTX,
1238 #ifdef CONFIG_KEYS
1239 __bpf_kfunc_start_defs();
1242 * bpf_lookup_user_key - lookup a key by its serial
1243 * @serial: key handle serial number
1244 * @flags: lookup-specific flags
1246 * Search a key with a given *serial* and the provided *flags*.
1247 * If found, increment the reference count of the key by one, and
1248 * return it in the bpf_key structure.
1250 * The bpf_key structure must be passed to bpf_key_put() when done
1251 * with it, so that the key reference count is decremented and the
1252 * bpf_key structure is freed.
1254 * Permission checks are deferred to the time the key is used by
1255 * one of the available key-specific kfuncs.
1257 * Set *flags* with KEY_LOOKUP_CREATE, to attempt creating a requested
1258 * special keyring (e.g. session keyring), if it doesn't yet exist.
1259 * Set *flags* with KEY_LOOKUP_PARTIAL, to lookup a key without waiting
1260 * for the key construction, and to retrieve uninstantiated keys (keys
1261 * without data attached to them).
1263 * Return: a bpf_key pointer with a valid key pointer if the key is found, a
1264 * NULL pointer otherwise.
1266 __bpf_kfunc struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
1268 key_ref_t key_ref;
1269 struct bpf_key *bkey;
1271 if (flags & ~KEY_LOOKUP_ALL)
1272 return NULL;
1275 * Permission check is deferred until the key is used, as the
1276 * intent of the caller is unknown here.
1278 key_ref = lookup_user_key(serial, flags, KEY_DEFER_PERM_CHECK);
1279 if (IS_ERR(key_ref))
1280 return NULL;
1282 bkey = kmalloc(sizeof(*bkey), GFP_KERNEL);
1283 if (!bkey) {
1284 key_put(key_ref_to_ptr(key_ref));
1285 return NULL;
1288 bkey->key = key_ref_to_ptr(key_ref);
1289 bkey->has_ref = true;
1291 return bkey;
1295 * bpf_lookup_system_key - lookup a key by a system-defined ID
1296 * @id: key ID
1298 * Obtain a bpf_key structure with a key pointer set to the passed key ID.
1299 * The key pointer is marked as invalid, to prevent bpf_key_put() from
1300 * attempting to decrement the key reference count on that pointer. The key
1301 * pointer set in such way is currently understood only by
1302 * verify_pkcs7_signature().
1304 * Set *id* to one of the values defined in include/linux/verification.h:
1305 * 0 for the primary keyring (immutable keyring of system keys);
1306 * VERIFY_USE_SECONDARY_KEYRING for both the primary and secondary keyring
1307 * (where keys can be added only if they are vouched for by existing keys
1308 * in those keyrings); VERIFY_USE_PLATFORM_KEYRING for the platform
1309 * keyring (primarily used by the integrity subsystem to verify a kexec'ed
1310 * kerned image and, possibly, the initramfs signature).
1312 * Return: a bpf_key pointer with an invalid key pointer set from the
1313 * pre-determined ID on success, a NULL pointer otherwise
1315 __bpf_kfunc struct bpf_key *bpf_lookup_system_key(u64 id)
1317 struct bpf_key *bkey;
1319 if (system_keyring_id_check(id) < 0)
1320 return NULL;
1322 bkey = kmalloc(sizeof(*bkey), GFP_ATOMIC);
1323 if (!bkey)
1324 return NULL;
1326 bkey->key = (struct key *)(unsigned long)id;
1327 bkey->has_ref = false;
1329 return bkey;
1333 * bpf_key_put - decrement key reference count if key is valid and free bpf_key
1334 * @bkey: bpf_key structure
1336 * Decrement the reference count of the key inside *bkey*, if the pointer
1337 * is valid, and free *bkey*.
1339 __bpf_kfunc void bpf_key_put(struct bpf_key *bkey)
1341 if (bkey->has_ref)
1342 key_put(bkey->key);
1344 kfree(bkey);
1347 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1349 * bpf_verify_pkcs7_signature - verify a PKCS#7 signature
1350 * @data_p: data to verify
1351 * @sig_p: signature of the data
1352 * @trusted_keyring: keyring with keys trusted for signature verification
1354 * Verify the PKCS#7 signature *sig_ptr* against the supplied *data_ptr*
1355 * with keys in a keyring referenced by *trusted_keyring*.
1357 * Return: 0 on success, a negative value on error.
1359 __bpf_kfunc int bpf_verify_pkcs7_signature(struct bpf_dynptr *data_p,
1360 struct bpf_dynptr *sig_p,
1361 struct bpf_key *trusted_keyring)
1363 struct bpf_dynptr_kern *data_ptr = (struct bpf_dynptr_kern *)data_p;
1364 struct bpf_dynptr_kern *sig_ptr = (struct bpf_dynptr_kern *)sig_p;
1365 const void *data, *sig;
1366 u32 data_len, sig_len;
1367 int ret;
1369 if (trusted_keyring->has_ref) {
1371 * Do the permission check deferred in bpf_lookup_user_key().
1372 * See bpf_lookup_user_key() for more details.
1374 * A call to key_task_permission() here would be redundant, as
1375 * it is already done by keyring_search() called by
1376 * find_asymmetric_key().
1378 ret = key_validate(trusted_keyring->key);
1379 if (ret < 0)
1380 return ret;
1383 data_len = __bpf_dynptr_size(data_ptr);
1384 data = __bpf_dynptr_data(data_ptr, data_len);
1385 sig_len = __bpf_dynptr_size(sig_ptr);
1386 sig = __bpf_dynptr_data(sig_ptr, sig_len);
1388 return verify_pkcs7_signature(data, data_len, sig, sig_len,
1389 trusted_keyring->key,
1390 VERIFYING_UNSPECIFIED_SIGNATURE, NULL,
1391 NULL);
1393 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
1395 __bpf_kfunc_end_defs();
1397 BTF_KFUNCS_START(key_sig_kfunc_set)
1398 BTF_ID_FLAGS(func, bpf_lookup_user_key, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE)
1399 BTF_ID_FLAGS(func, bpf_lookup_system_key, KF_ACQUIRE | KF_RET_NULL)
1400 BTF_ID_FLAGS(func, bpf_key_put, KF_RELEASE)
1401 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1402 BTF_ID_FLAGS(func, bpf_verify_pkcs7_signature, KF_SLEEPABLE)
1403 #endif
1404 BTF_KFUNCS_END(key_sig_kfunc_set)
1406 static const struct btf_kfunc_id_set bpf_key_sig_kfunc_set = {
1407 .owner = THIS_MODULE,
1408 .set = &key_sig_kfunc_set,
1411 static int __init bpf_key_sig_kfuncs_init(void)
1413 return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING,
1414 &bpf_key_sig_kfunc_set);
1417 late_initcall(bpf_key_sig_kfuncs_init);
1418 #endif /* CONFIG_KEYS */
1420 static const struct bpf_func_proto *
1421 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1423 switch (func_id) {
1424 case BPF_FUNC_map_lookup_elem:
1425 return &bpf_map_lookup_elem_proto;
1426 case BPF_FUNC_map_update_elem:
1427 return &bpf_map_update_elem_proto;
1428 case BPF_FUNC_map_delete_elem:
1429 return &bpf_map_delete_elem_proto;
1430 case BPF_FUNC_map_push_elem:
1431 return &bpf_map_push_elem_proto;
1432 case BPF_FUNC_map_pop_elem:
1433 return &bpf_map_pop_elem_proto;
1434 case BPF_FUNC_map_peek_elem:
1435 return &bpf_map_peek_elem_proto;
1436 case BPF_FUNC_map_lookup_percpu_elem:
1437 return &bpf_map_lookup_percpu_elem_proto;
1438 case BPF_FUNC_ktime_get_ns:
1439 return &bpf_ktime_get_ns_proto;
1440 case BPF_FUNC_ktime_get_boot_ns:
1441 return &bpf_ktime_get_boot_ns_proto;
1442 case BPF_FUNC_tail_call:
1443 return &bpf_tail_call_proto;
1444 case BPF_FUNC_get_current_task:
1445 return &bpf_get_current_task_proto;
1446 case BPF_FUNC_get_current_task_btf:
1447 return &bpf_get_current_task_btf_proto;
1448 case BPF_FUNC_task_pt_regs:
1449 return &bpf_task_pt_regs_proto;
1450 case BPF_FUNC_get_current_uid_gid:
1451 return &bpf_get_current_uid_gid_proto;
1452 case BPF_FUNC_get_current_comm:
1453 return &bpf_get_current_comm_proto;
1454 case BPF_FUNC_trace_printk:
1455 return bpf_get_trace_printk_proto();
1456 case BPF_FUNC_get_smp_processor_id:
1457 return &bpf_get_smp_processor_id_proto;
1458 case BPF_FUNC_get_numa_node_id:
1459 return &bpf_get_numa_node_id_proto;
1460 case BPF_FUNC_perf_event_read:
1461 return &bpf_perf_event_read_proto;
1462 case BPF_FUNC_get_prandom_u32:
1463 return &bpf_get_prandom_u32_proto;
1464 case BPF_FUNC_probe_write_user:
1465 return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
1466 NULL : bpf_get_probe_write_proto();
1467 case BPF_FUNC_probe_read_user:
1468 return &bpf_probe_read_user_proto;
1469 case BPF_FUNC_probe_read_kernel:
1470 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1471 NULL : &bpf_probe_read_kernel_proto;
1472 case BPF_FUNC_probe_read_user_str:
1473 return &bpf_probe_read_user_str_proto;
1474 case BPF_FUNC_probe_read_kernel_str:
1475 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1476 NULL : &bpf_probe_read_kernel_str_proto;
1477 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1478 case BPF_FUNC_probe_read:
1479 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1480 NULL : &bpf_probe_read_compat_proto;
1481 case BPF_FUNC_probe_read_str:
1482 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1483 NULL : &bpf_probe_read_compat_str_proto;
1484 #endif
1485 #ifdef CONFIG_CGROUPS
1486 case BPF_FUNC_cgrp_storage_get:
1487 return &bpf_cgrp_storage_get_proto;
1488 case BPF_FUNC_cgrp_storage_delete:
1489 return &bpf_cgrp_storage_delete_proto;
1490 case BPF_FUNC_current_task_under_cgroup:
1491 return &bpf_current_task_under_cgroup_proto;
1492 #endif
1493 case BPF_FUNC_send_signal:
1494 return &bpf_send_signal_proto;
1495 case BPF_FUNC_send_signal_thread:
1496 return &bpf_send_signal_thread_proto;
1497 case BPF_FUNC_perf_event_read_value:
1498 return &bpf_perf_event_read_value_proto;
1499 case BPF_FUNC_ringbuf_output:
1500 return &bpf_ringbuf_output_proto;
1501 case BPF_FUNC_ringbuf_reserve:
1502 return &bpf_ringbuf_reserve_proto;
1503 case BPF_FUNC_ringbuf_submit:
1504 return &bpf_ringbuf_submit_proto;
1505 case BPF_FUNC_ringbuf_discard:
1506 return &bpf_ringbuf_discard_proto;
1507 case BPF_FUNC_ringbuf_query:
1508 return &bpf_ringbuf_query_proto;
1509 case BPF_FUNC_jiffies64:
1510 return &bpf_jiffies64_proto;
1511 case BPF_FUNC_get_task_stack:
1512 return prog->sleepable ? &bpf_get_task_stack_sleepable_proto
1513 : &bpf_get_task_stack_proto;
1514 case BPF_FUNC_copy_from_user:
1515 return &bpf_copy_from_user_proto;
1516 case BPF_FUNC_copy_from_user_task:
1517 return &bpf_copy_from_user_task_proto;
1518 case BPF_FUNC_snprintf_btf:
1519 return &bpf_snprintf_btf_proto;
1520 case BPF_FUNC_per_cpu_ptr:
1521 return &bpf_per_cpu_ptr_proto;
1522 case BPF_FUNC_this_cpu_ptr:
1523 return &bpf_this_cpu_ptr_proto;
1524 case BPF_FUNC_task_storage_get:
1525 if (bpf_prog_check_recur(prog))
1526 return &bpf_task_storage_get_recur_proto;
1527 return &bpf_task_storage_get_proto;
1528 case BPF_FUNC_task_storage_delete:
1529 if (bpf_prog_check_recur(prog))
1530 return &bpf_task_storage_delete_recur_proto;
1531 return &bpf_task_storage_delete_proto;
1532 case BPF_FUNC_for_each_map_elem:
1533 return &bpf_for_each_map_elem_proto;
1534 case BPF_FUNC_snprintf:
1535 return &bpf_snprintf_proto;
1536 case BPF_FUNC_get_func_ip:
1537 return &bpf_get_func_ip_proto_tracing;
1538 case BPF_FUNC_get_branch_snapshot:
1539 return &bpf_get_branch_snapshot_proto;
1540 case BPF_FUNC_find_vma:
1541 return &bpf_find_vma_proto;
1542 case BPF_FUNC_trace_vprintk:
1543 return bpf_get_trace_vprintk_proto();
1544 default:
1545 return bpf_base_func_proto(func_id, prog);
1549 static bool is_kprobe_multi(const struct bpf_prog *prog)
1551 return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ||
1552 prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION;
1555 static inline bool is_kprobe_session(const struct bpf_prog *prog)
1557 return prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION;
1560 static const struct bpf_func_proto *
1561 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1563 switch (func_id) {
1564 case BPF_FUNC_perf_event_output:
1565 return &bpf_perf_event_output_proto;
1566 case BPF_FUNC_get_stackid:
1567 return &bpf_get_stackid_proto;
1568 case BPF_FUNC_get_stack:
1569 return prog->sleepable ? &bpf_get_stack_sleepable_proto : &bpf_get_stack_proto;
1570 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1571 case BPF_FUNC_override_return:
1572 return &bpf_override_return_proto;
1573 #endif
1574 case BPF_FUNC_get_func_ip:
1575 if (is_kprobe_multi(prog))
1576 return &bpf_get_func_ip_proto_kprobe_multi;
1577 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
1578 return &bpf_get_func_ip_proto_uprobe_multi;
1579 return &bpf_get_func_ip_proto_kprobe;
1580 case BPF_FUNC_get_attach_cookie:
1581 if (is_kprobe_multi(prog))
1582 return &bpf_get_attach_cookie_proto_kmulti;
1583 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
1584 return &bpf_get_attach_cookie_proto_umulti;
1585 return &bpf_get_attach_cookie_proto_trace;
1586 default:
1587 return bpf_tracing_func_proto(func_id, prog);
1591 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
1592 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1593 const struct bpf_prog *prog,
1594 struct bpf_insn_access_aux *info)
1596 if (off < 0 || off >= sizeof(struct pt_regs))
1597 return false;
1598 if (type != BPF_READ)
1599 return false;
1600 if (off % size != 0)
1601 return false;
1603 * Assertion for 32 bit to make sure last 8 byte access
1604 * (BPF_DW) to the last 4 byte member is disallowed.
1606 if (off + size > sizeof(struct pt_regs))
1607 return false;
1609 return true;
1612 const struct bpf_verifier_ops kprobe_verifier_ops = {
1613 .get_func_proto = kprobe_prog_func_proto,
1614 .is_valid_access = kprobe_prog_is_valid_access,
1617 const struct bpf_prog_ops kprobe_prog_ops = {
1620 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1621 u64, flags, void *, data, u64, size)
1623 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1626 * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1627 * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1628 * from there and call the same bpf_perf_event_output() helper inline.
1630 return ____bpf_perf_event_output(regs, map, flags, data, size);
1633 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1634 .func = bpf_perf_event_output_tp,
1635 .gpl_only = true,
1636 .ret_type = RET_INTEGER,
1637 .arg1_type = ARG_PTR_TO_CTX,
1638 .arg2_type = ARG_CONST_MAP_PTR,
1639 .arg3_type = ARG_ANYTHING,
1640 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1641 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1644 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1645 u64, flags)
1647 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1650 * Same comment as in bpf_perf_event_output_tp(), only that this time
1651 * the other helper's function body cannot be inlined due to being
1652 * external, thus we need to call raw helper function.
1654 return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1655 flags, 0, 0);
1658 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1659 .func = bpf_get_stackid_tp,
1660 .gpl_only = true,
1661 .ret_type = RET_INTEGER,
1662 .arg1_type = ARG_PTR_TO_CTX,
1663 .arg2_type = ARG_CONST_MAP_PTR,
1664 .arg3_type = ARG_ANYTHING,
1667 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1668 u64, flags)
1670 struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1672 return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1673 (unsigned long) size, flags, 0);
1676 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1677 .func = bpf_get_stack_tp,
1678 .gpl_only = true,
1679 .ret_type = RET_INTEGER,
1680 .arg1_type = ARG_PTR_TO_CTX,
1681 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1682 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1683 .arg4_type = ARG_ANYTHING,
1686 static const struct bpf_func_proto *
1687 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1689 switch (func_id) {
1690 case BPF_FUNC_perf_event_output:
1691 return &bpf_perf_event_output_proto_tp;
1692 case BPF_FUNC_get_stackid:
1693 return &bpf_get_stackid_proto_tp;
1694 case BPF_FUNC_get_stack:
1695 return &bpf_get_stack_proto_tp;
1696 case BPF_FUNC_get_attach_cookie:
1697 return &bpf_get_attach_cookie_proto_trace;
1698 default:
1699 return bpf_tracing_func_proto(func_id, prog);
1703 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1704 const struct bpf_prog *prog,
1705 struct bpf_insn_access_aux *info)
1707 if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1708 return false;
1709 if (type != BPF_READ)
1710 return false;
1711 if (off % size != 0)
1712 return false;
1714 BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1715 return true;
1718 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1719 .get_func_proto = tp_prog_func_proto,
1720 .is_valid_access = tp_prog_is_valid_access,
1723 const struct bpf_prog_ops tracepoint_prog_ops = {
1726 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1727 struct bpf_perf_event_value *, buf, u32, size)
1729 int err = -EINVAL;
1731 if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1732 goto clear;
1733 err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1734 &buf->running);
1735 if (unlikely(err))
1736 goto clear;
1737 return 0;
1738 clear:
1739 memset(buf, 0, size);
1740 return err;
1743 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1744 .func = bpf_perf_prog_read_value,
1745 .gpl_only = true,
1746 .ret_type = RET_INTEGER,
1747 .arg1_type = ARG_PTR_TO_CTX,
1748 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
1749 .arg3_type = ARG_CONST_SIZE,
1752 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1753 void *, buf, u32, size, u64, flags)
1755 static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1756 struct perf_branch_stack *br_stack = ctx->data->br_stack;
1757 u32 to_copy;
1759 if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1760 return -EINVAL;
1762 if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
1763 return -ENOENT;
1765 if (unlikely(!br_stack))
1766 return -ENOENT;
1768 if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1769 return br_stack->nr * br_entry_size;
1771 if (!buf || (size % br_entry_size != 0))
1772 return -EINVAL;
1774 to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1775 memcpy(buf, br_stack->entries, to_copy);
1777 return to_copy;
1780 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1781 .func = bpf_read_branch_records,
1782 .gpl_only = true,
1783 .ret_type = RET_INTEGER,
1784 .arg1_type = ARG_PTR_TO_CTX,
1785 .arg2_type = ARG_PTR_TO_MEM_OR_NULL,
1786 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1787 .arg4_type = ARG_ANYTHING,
1790 static const struct bpf_func_proto *
1791 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1793 switch (func_id) {
1794 case BPF_FUNC_perf_event_output:
1795 return &bpf_perf_event_output_proto_tp;
1796 case BPF_FUNC_get_stackid:
1797 return &bpf_get_stackid_proto_pe;
1798 case BPF_FUNC_get_stack:
1799 return &bpf_get_stack_proto_pe;
1800 case BPF_FUNC_perf_prog_read_value:
1801 return &bpf_perf_prog_read_value_proto;
1802 case BPF_FUNC_read_branch_records:
1803 return &bpf_read_branch_records_proto;
1804 case BPF_FUNC_get_attach_cookie:
1805 return &bpf_get_attach_cookie_proto_pe;
1806 default:
1807 return bpf_tracing_func_proto(func_id, prog);
1812 * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1813 * to avoid potential recursive reuse issue when/if tracepoints are added
1814 * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1816 * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1817 * in normal, irq, and nmi context.
1819 struct bpf_raw_tp_regs {
1820 struct pt_regs regs[3];
1822 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1823 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
1824 static struct pt_regs *get_bpf_raw_tp_regs(void)
1826 struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1827 int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1829 if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1830 this_cpu_dec(bpf_raw_tp_nest_level);
1831 return ERR_PTR(-EBUSY);
1834 return &tp_regs->regs[nest_level - 1];
1837 static void put_bpf_raw_tp_regs(void)
1839 this_cpu_dec(bpf_raw_tp_nest_level);
1842 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1843 struct bpf_map *, map, u64, flags, void *, data, u64, size)
1845 struct pt_regs *regs = get_bpf_raw_tp_regs();
1846 int ret;
1848 if (IS_ERR(regs))
1849 return PTR_ERR(regs);
1851 perf_fetch_caller_regs(regs);
1852 ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1854 put_bpf_raw_tp_regs();
1855 return ret;
1858 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1859 .func = bpf_perf_event_output_raw_tp,
1860 .gpl_only = true,
1861 .ret_type = RET_INTEGER,
1862 .arg1_type = ARG_PTR_TO_CTX,
1863 .arg2_type = ARG_CONST_MAP_PTR,
1864 .arg3_type = ARG_ANYTHING,
1865 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1866 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
1869 extern const struct bpf_func_proto bpf_skb_output_proto;
1870 extern const struct bpf_func_proto bpf_xdp_output_proto;
1871 extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
1873 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1874 struct bpf_map *, map, u64, flags)
1876 struct pt_regs *regs = get_bpf_raw_tp_regs();
1877 int ret;
1879 if (IS_ERR(regs))
1880 return PTR_ERR(regs);
1882 perf_fetch_caller_regs(regs);
1883 /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1884 ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1885 flags, 0, 0);
1886 put_bpf_raw_tp_regs();
1887 return ret;
1890 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1891 .func = bpf_get_stackid_raw_tp,
1892 .gpl_only = true,
1893 .ret_type = RET_INTEGER,
1894 .arg1_type = ARG_PTR_TO_CTX,
1895 .arg2_type = ARG_CONST_MAP_PTR,
1896 .arg3_type = ARG_ANYTHING,
1899 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1900 void *, buf, u32, size, u64, flags)
1902 struct pt_regs *regs = get_bpf_raw_tp_regs();
1903 int ret;
1905 if (IS_ERR(regs))
1906 return PTR_ERR(regs);
1908 perf_fetch_caller_regs(regs);
1909 ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1910 (unsigned long) size, flags, 0);
1911 put_bpf_raw_tp_regs();
1912 return ret;
1915 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1916 .func = bpf_get_stack_raw_tp,
1917 .gpl_only = true,
1918 .ret_type = RET_INTEGER,
1919 .arg1_type = ARG_PTR_TO_CTX,
1920 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1921 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
1922 .arg4_type = ARG_ANYTHING,
1925 static const struct bpf_func_proto *
1926 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1928 switch (func_id) {
1929 case BPF_FUNC_perf_event_output:
1930 return &bpf_perf_event_output_proto_raw_tp;
1931 case BPF_FUNC_get_stackid:
1932 return &bpf_get_stackid_proto_raw_tp;
1933 case BPF_FUNC_get_stack:
1934 return &bpf_get_stack_proto_raw_tp;
1935 case BPF_FUNC_get_attach_cookie:
1936 return &bpf_get_attach_cookie_proto_tracing;
1937 default:
1938 return bpf_tracing_func_proto(func_id, prog);
1942 const struct bpf_func_proto *
1943 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1945 const struct bpf_func_proto *fn;
1947 switch (func_id) {
1948 #ifdef CONFIG_NET
1949 case BPF_FUNC_skb_output:
1950 return &bpf_skb_output_proto;
1951 case BPF_FUNC_xdp_output:
1952 return &bpf_xdp_output_proto;
1953 case BPF_FUNC_skc_to_tcp6_sock:
1954 return &bpf_skc_to_tcp6_sock_proto;
1955 case BPF_FUNC_skc_to_tcp_sock:
1956 return &bpf_skc_to_tcp_sock_proto;
1957 case BPF_FUNC_skc_to_tcp_timewait_sock:
1958 return &bpf_skc_to_tcp_timewait_sock_proto;
1959 case BPF_FUNC_skc_to_tcp_request_sock:
1960 return &bpf_skc_to_tcp_request_sock_proto;
1961 case BPF_FUNC_skc_to_udp6_sock:
1962 return &bpf_skc_to_udp6_sock_proto;
1963 case BPF_FUNC_skc_to_unix_sock:
1964 return &bpf_skc_to_unix_sock_proto;
1965 case BPF_FUNC_skc_to_mptcp_sock:
1966 return &bpf_skc_to_mptcp_sock_proto;
1967 case BPF_FUNC_sk_storage_get:
1968 return &bpf_sk_storage_get_tracing_proto;
1969 case BPF_FUNC_sk_storage_delete:
1970 return &bpf_sk_storage_delete_tracing_proto;
1971 case BPF_FUNC_sock_from_file:
1972 return &bpf_sock_from_file_proto;
1973 case BPF_FUNC_get_socket_cookie:
1974 return &bpf_get_socket_ptr_cookie_proto;
1975 case BPF_FUNC_xdp_get_buff_len:
1976 return &bpf_xdp_get_buff_len_trace_proto;
1977 #endif
1978 case BPF_FUNC_seq_printf:
1979 return prog->expected_attach_type == BPF_TRACE_ITER ?
1980 &bpf_seq_printf_proto :
1981 NULL;
1982 case BPF_FUNC_seq_write:
1983 return prog->expected_attach_type == BPF_TRACE_ITER ?
1984 &bpf_seq_write_proto :
1985 NULL;
1986 case BPF_FUNC_seq_printf_btf:
1987 return prog->expected_attach_type == BPF_TRACE_ITER ?
1988 &bpf_seq_printf_btf_proto :
1989 NULL;
1990 case BPF_FUNC_d_path:
1991 return &bpf_d_path_proto;
1992 case BPF_FUNC_get_func_arg:
1993 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
1994 case BPF_FUNC_get_func_ret:
1995 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
1996 case BPF_FUNC_get_func_arg_cnt:
1997 return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
1998 case BPF_FUNC_get_attach_cookie:
1999 if (prog->type == BPF_PROG_TYPE_TRACING &&
2000 prog->expected_attach_type == BPF_TRACE_RAW_TP)
2001 return &bpf_get_attach_cookie_proto_tracing;
2002 return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL;
2003 default:
2004 fn = raw_tp_prog_func_proto(func_id, prog);
2005 if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
2006 fn = bpf_iter_get_func_proto(func_id, prog);
2007 return fn;
2011 static bool raw_tp_prog_is_valid_access(int off, int size,
2012 enum bpf_access_type type,
2013 const struct bpf_prog *prog,
2014 struct bpf_insn_access_aux *info)
2016 return bpf_tracing_ctx_access(off, size, type);
2019 static bool tracing_prog_is_valid_access(int off, int size,
2020 enum bpf_access_type type,
2021 const struct bpf_prog *prog,
2022 struct bpf_insn_access_aux *info)
2024 return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
2027 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
2028 const union bpf_attr *kattr,
2029 union bpf_attr __user *uattr)
2031 return -ENOTSUPP;
2034 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
2035 .get_func_proto = raw_tp_prog_func_proto,
2036 .is_valid_access = raw_tp_prog_is_valid_access,
2039 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
2040 #ifdef CONFIG_NET
2041 .test_run = bpf_prog_test_run_raw_tp,
2042 #endif
2045 const struct bpf_verifier_ops tracing_verifier_ops = {
2046 .get_func_proto = tracing_prog_func_proto,
2047 .is_valid_access = tracing_prog_is_valid_access,
2050 const struct bpf_prog_ops tracing_prog_ops = {
2051 .test_run = bpf_prog_test_run_tracing,
2054 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
2055 enum bpf_access_type type,
2056 const struct bpf_prog *prog,
2057 struct bpf_insn_access_aux *info)
2059 if (off == 0) {
2060 if (size != sizeof(u64) || type != BPF_READ)
2061 return false;
2062 info->reg_type = PTR_TO_TP_BUFFER;
2064 return raw_tp_prog_is_valid_access(off, size, type, prog, info);
2067 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
2068 .get_func_proto = raw_tp_prog_func_proto,
2069 .is_valid_access = raw_tp_writable_prog_is_valid_access,
2072 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
2075 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
2076 const struct bpf_prog *prog,
2077 struct bpf_insn_access_aux *info)
2079 const int size_u64 = sizeof(u64);
2081 if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
2082 return false;
2083 if (type != BPF_READ)
2084 return false;
2085 if (off % size != 0) {
2086 if (sizeof(unsigned long) != 4)
2087 return false;
2088 if (size != 8)
2089 return false;
2090 if (off % size != 4)
2091 return false;
2094 switch (off) {
2095 case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
2096 bpf_ctx_record_field_size(info, size_u64);
2097 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2098 return false;
2099 break;
2100 case bpf_ctx_range(struct bpf_perf_event_data, addr):
2101 bpf_ctx_record_field_size(info, size_u64);
2102 if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2103 return false;
2104 break;
2105 default:
2106 if (size != sizeof(long))
2107 return false;
2110 return true;
2113 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
2114 const struct bpf_insn *si,
2115 struct bpf_insn *insn_buf,
2116 struct bpf_prog *prog, u32 *target_size)
2118 struct bpf_insn *insn = insn_buf;
2120 switch (si->off) {
2121 case offsetof(struct bpf_perf_event_data, sample_period):
2122 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2123 data), si->dst_reg, si->src_reg,
2124 offsetof(struct bpf_perf_event_data_kern, data));
2125 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2126 bpf_target_off(struct perf_sample_data, period, 8,
2127 target_size));
2128 break;
2129 case offsetof(struct bpf_perf_event_data, addr):
2130 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2131 data), si->dst_reg, si->src_reg,
2132 offsetof(struct bpf_perf_event_data_kern, data));
2133 *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2134 bpf_target_off(struct perf_sample_data, addr, 8,
2135 target_size));
2136 break;
2137 default:
2138 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2139 regs), si->dst_reg, si->src_reg,
2140 offsetof(struct bpf_perf_event_data_kern, regs));
2141 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
2142 si->off);
2143 break;
2146 return insn - insn_buf;
2149 const struct bpf_verifier_ops perf_event_verifier_ops = {
2150 .get_func_proto = pe_prog_func_proto,
2151 .is_valid_access = pe_prog_is_valid_access,
2152 .convert_ctx_access = pe_prog_convert_ctx_access,
2155 const struct bpf_prog_ops perf_event_prog_ops = {
2158 static DEFINE_MUTEX(bpf_event_mutex);
2160 #define BPF_TRACE_MAX_PROGS 64
2162 int perf_event_attach_bpf_prog(struct perf_event *event,
2163 struct bpf_prog *prog,
2164 u64 bpf_cookie)
2166 struct bpf_prog_array *old_array;
2167 struct bpf_prog_array *new_array;
2168 int ret = -EEXIST;
2171 * Kprobe override only works if they are on the function entry,
2172 * and only if they are on the opt-in list.
2174 if (prog->kprobe_override &&
2175 (!trace_kprobe_on_func_entry(event->tp_event) ||
2176 !trace_kprobe_error_injectable(event->tp_event)))
2177 return -EINVAL;
2179 mutex_lock(&bpf_event_mutex);
2181 if (event->prog)
2182 goto unlock;
2184 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2185 if (old_array &&
2186 bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
2187 ret = -E2BIG;
2188 goto unlock;
2191 ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
2192 if (ret < 0)
2193 goto unlock;
2195 /* set the new array to event->tp_event and set event->prog */
2196 event->prog = prog;
2197 event->bpf_cookie = bpf_cookie;
2198 rcu_assign_pointer(event->tp_event->prog_array, new_array);
2199 bpf_prog_array_free_sleepable(old_array);
2201 unlock:
2202 mutex_unlock(&bpf_event_mutex);
2203 return ret;
2206 void perf_event_detach_bpf_prog(struct perf_event *event)
2208 struct bpf_prog_array *old_array;
2209 struct bpf_prog_array *new_array;
2210 int ret;
2212 mutex_lock(&bpf_event_mutex);
2214 if (!event->prog)
2215 goto unlock;
2217 old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2218 ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
2219 if (ret == -ENOENT)
2220 goto unlock;
2221 if (ret < 0) {
2222 bpf_prog_array_delete_safe(old_array, event->prog);
2223 } else {
2224 rcu_assign_pointer(event->tp_event->prog_array, new_array);
2225 bpf_prog_array_free_sleepable(old_array);
2228 bpf_prog_put(event->prog);
2229 event->prog = NULL;
2231 unlock:
2232 mutex_unlock(&bpf_event_mutex);
2235 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
2237 struct perf_event_query_bpf __user *uquery = info;
2238 struct perf_event_query_bpf query = {};
2239 struct bpf_prog_array *progs;
2240 u32 *ids, prog_cnt, ids_len;
2241 int ret;
2243 if (!perfmon_capable())
2244 return -EPERM;
2245 if (event->attr.type != PERF_TYPE_TRACEPOINT)
2246 return -EINVAL;
2247 if (copy_from_user(&query, uquery, sizeof(query)))
2248 return -EFAULT;
2250 ids_len = query.ids_len;
2251 if (ids_len > BPF_TRACE_MAX_PROGS)
2252 return -E2BIG;
2253 ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
2254 if (!ids)
2255 return -ENOMEM;
2257 * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
2258 * is required when user only wants to check for uquery->prog_cnt.
2259 * There is no need to check for it since the case is handled
2260 * gracefully in bpf_prog_array_copy_info.
2263 mutex_lock(&bpf_event_mutex);
2264 progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
2265 ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
2266 mutex_unlock(&bpf_event_mutex);
2268 if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
2269 copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
2270 ret = -EFAULT;
2272 kfree(ids);
2273 return ret;
2276 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
2277 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
2279 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
2281 struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
2283 for (; btp < __stop__bpf_raw_tp; btp++) {
2284 if (!strcmp(btp->tp->name, name))
2285 return btp;
2288 return bpf_get_raw_tracepoint_module(name);
2291 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
2293 struct module *mod;
2295 preempt_disable();
2296 mod = __module_address((unsigned long)btp);
2297 module_put(mod);
2298 preempt_enable();
2301 static __always_inline
2302 void __bpf_trace_run(struct bpf_raw_tp_link *link, u64 *args)
2304 struct bpf_prog *prog = link->link.prog;
2305 struct bpf_run_ctx *old_run_ctx;
2306 struct bpf_trace_run_ctx run_ctx;
2308 cant_sleep();
2309 if (unlikely(this_cpu_inc_return(*(prog->active)) != 1)) {
2310 bpf_prog_inc_misses_counter(prog);
2311 goto out;
2314 run_ctx.bpf_cookie = link->cookie;
2315 old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
2317 rcu_read_lock();
2318 (void) bpf_prog_run(prog, args);
2319 rcu_read_unlock();
2321 bpf_reset_run_ctx(old_run_ctx);
2322 out:
2323 this_cpu_dec(*(prog->active));
2326 #define UNPACK(...) __VA_ARGS__
2327 #define REPEAT_1(FN, DL, X, ...) FN(X)
2328 #define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
2329 #define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
2330 #define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
2331 #define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
2332 #define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
2333 #define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
2334 #define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
2335 #define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
2336 #define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
2337 #define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
2338 #define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
2339 #define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
2341 #define SARG(X) u64 arg##X
2342 #define COPY(X) args[X] = arg##X
2344 #define __DL_COM (,)
2345 #define __DL_SEM (;)
2347 #define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
2349 #define BPF_TRACE_DEFN_x(x) \
2350 void bpf_trace_run##x(struct bpf_raw_tp_link *link, \
2351 REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
2353 u64 args[x]; \
2354 REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
2355 __bpf_trace_run(link, args); \
2357 EXPORT_SYMBOL_GPL(bpf_trace_run##x)
2358 BPF_TRACE_DEFN_x(1);
2359 BPF_TRACE_DEFN_x(2);
2360 BPF_TRACE_DEFN_x(3);
2361 BPF_TRACE_DEFN_x(4);
2362 BPF_TRACE_DEFN_x(5);
2363 BPF_TRACE_DEFN_x(6);
2364 BPF_TRACE_DEFN_x(7);
2365 BPF_TRACE_DEFN_x(8);
2366 BPF_TRACE_DEFN_x(9);
2367 BPF_TRACE_DEFN_x(10);
2368 BPF_TRACE_DEFN_x(11);
2369 BPF_TRACE_DEFN_x(12);
2371 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
2373 struct tracepoint *tp = btp->tp;
2374 struct bpf_prog *prog = link->link.prog;
2377 * check that program doesn't access arguments beyond what's
2378 * available in this tracepoint
2380 if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
2381 return -EINVAL;
2383 if (prog->aux->max_tp_access > btp->writable_size)
2384 return -EINVAL;
2386 return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func, link);
2389 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
2391 return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, link);
2394 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
2395 u32 *fd_type, const char **buf,
2396 u64 *probe_offset, u64 *probe_addr,
2397 unsigned long *missed)
2399 bool is_tracepoint, is_syscall_tp;
2400 struct bpf_prog *prog;
2401 int flags, err = 0;
2403 prog = event->prog;
2404 if (!prog)
2405 return -ENOENT;
2407 /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
2408 if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
2409 return -EOPNOTSUPP;
2411 *prog_id = prog->aux->id;
2412 flags = event->tp_event->flags;
2413 is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
2414 is_syscall_tp = is_syscall_trace_event(event->tp_event);
2416 if (is_tracepoint || is_syscall_tp) {
2417 *buf = is_tracepoint ? event->tp_event->tp->name
2418 : event->tp_event->name;
2419 /* We allow NULL pointer for tracepoint */
2420 if (fd_type)
2421 *fd_type = BPF_FD_TYPE_TRACEPOINT;
2422 if (probe_offset)
2423 *probe_offset = 0x0;
2424 if (probe_addr)
2425 *probe_addr = 0x0;
2426 } else {
2427 /* kprobe/uprobe */
2428 err = -EOPNOTSUPP;
2429 #ifdef CONFIG_KPROBE_EVENTS
2430 if (flags & TRACE_EVENT_FL_KPROBE)
2431 err = bpf_get_kprobe_info(event, fd_type, buf,
2432 probe_offset, probe_addr, missed,
2433 event->attr.type == PERF_TYPE_TRACEPOINT);
2434 #endif
2435 #ifdef CONFIG_UPROBE_EVENTS
2436 if (flags & TRACE_EVENT_FL_UPROBE)
2437 err = bpf_get_uprobe_info(event, fd_type, buf,
2438 probe_offset, probe_addr,
2439 event->attr.type == PERF_TYPE_TRACEPOINT);
2440 #endif
2443 return err;
2446 static int __init send_signal_irq_work_init(void)
2448 int cpu;
2449 struct send_signal_irq_work *work;
2451 for_each_possible_cpu(cpu) {
2452 work = per_cpu_ptr(&send_signal_work, cpu);
2453 init_irq_work(&work->irq_work, do_bpf_send_signal);
2455 return 0;
2458 subsys_initcall(send_signal_irq_work_init);
2460 #ifdef CONFIG_MODULES
2461 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
2462 void *module)
2464 struct bpf_trace_module *btm, *tmp;
2465 struct module *mod = module;
2466 int ret = 0;
2468 if (mod->num_bpf_raw_events == 0 ||
2469 (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
2470 goto out;
2472 mutex_lock(&bpf_module_mutex);
2474 switch (op) {
2475 case MODULE_STATE_COMING:
2476 btm = kzalloc(sizeof(*btm), GFP_KERNEL);
2477 if (btm) {
2478 btm->module = module;
2479 list_add(&btm->list, &bpf_trace_modules);
2480 } else {
2481 ret = -ENOMEM;
2483 break;
2484 case MODULE_STATE_GOING:
2485 list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
2486 if (btm->module == module) {
2487 list_del(&btm->list);
2488 kfree(btm);
2489 break;
2492 break;
2495 mutex_unlock(&bpf_module_mutex);
2497 out:
2498 return notifier_from_errno(ret);
2501 static struct notifier_block bpf_module_nb = {
2502 .notifier_call = bpf_event_notify,
2505 static int __init bpf_event_init(void)
2507 register_module_notifier(&bpf_module_nb);
2508 return 0;
2511 fs_initcall(bpf_event_init);
2512 #endif /* CONFIG_MODULES */
2514 struct bpf_session_run_ctx {
2515 struct bpf_run_ctx run_ctx;
2516 bool is_return;
2517 void *data;
2520 #ifdef CONFIG_FPROBE
2521 struct bpf_kprobe_multi_link {
2522 struct bpf_link link;
2523 struct fprobe fp;
2524 unsigned long *addrs;
2525 u64 *cookies;
2526 u32 cnt;
2527 u32 mods_cnt;
2528 struct module **mods;
2529 u32 flags;
2532 struct bpf_kprobe_multi_run_ctx {
2533 struct bpf_session_run_ctx session_ctx;
2534 struct bpf_kprobe_multi_link *link;
2535 unsigned long entry_ip;
2538 struct user_syms {
2539 const char **syms;
2540 char *buf;
2543 static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
2545 unsigned long __user usymbol;
2546 const char **syms = NULL;
2547 char *buf = NULL, *p;
2548 int err = -ENOMEM;
2549 unsigned int i;
2551 syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
2552 if (!syms)
2553 goto error;
2555 buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
2556 if (!buf)
2557 goto error;
2559 for (p = buf, i = 0; i < cnt; i++) {
2560 if (__get_user(usymbol, usyms + i)) {
2561 err = -EFAULT;
2562 goto error;
2564 err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN);
2565 if (err == KSYM_NAME_LEN)
2566 err = -E2BIG;
2567 if (err < 0)
2568 goto error;
2569 syms[i] = p;
2570 p += err + 1;
2573 us->syms = syms;
2574 us->buf = buf;
2575 return 0;
2577 error:
2578 if (err) {
2579 kvfree(syms);
2580 kvfree(buf);
2582 return err;
2585 static void kprobe_multi_put_modules(struct module **mods, u32 cnt)
2587 u32 i;
2589 for (i = 0; i < cnt; i++)
2590 module_put(mods[i]);
2593 static void free_user_syms(struct user_syms *us)
2595 kvfree(us->syms);
2596 kvfree(us->buf);
2599 static void bpf_kprobe_multi_link_release(struct bpf_link *link)
2601 struct bpf_kprobe_multi_link *kmulti_link;
2603 kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2604 unregister_fprobe(&kmulti_link->fp);
2605 kprobe_multi_put_modules(kmulti_link->mods, kmulti_link->mods_cnt);
2608 static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
2610 struct bpf_kprobe_multi_link *kmulti_link;
2612 kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2613 kvfree(kmulti_link->addrs);
2614 kvfree(kmulti_link->cookies);
2615 kfree(kmulti_link->mods);
2616 kfree(kmulti_link);
2619 static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link,
2620 struct bpf_link_info *info)
2622 u64 __user *ucookies = u64_to_user_ptr(info->kprobe_multi.cookies);
2623 u64 __user *uaddrs = u64_to_user_ptr(info->kprobe_multi.addrs);
2624 struct bpf_kprobe_multi_link *kmulti_link;
2625 u32 ucount = info->kprobe_multi.count;
2626 int err = 0, i;
2628 if (!uaddrs ^ !ucount)
2629 return -EINVAL;
2630 if (ucookies && !ucount)
2631 return -EINVAL;
2633 kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2634 info->kprobe_multi.count = kmulti_link->cnt;
2635 info->kprobe_multi.flags = kmulti_link->flags;
2636 info->kprobe_multi.missed = kmulti_link->fp.nmissed;
2638 if (!uaddrs)
2639 return 0;
2640 if (ucount < kmulti_link->cnt)
2641 err = -ENOSPC;
2642 else
2643 ucount = kmulti_link->cnt;
2645 if (ucookies) {
2646 if (kmulti_link->cookies) {
2647 if (copy_to_user(ucookies, kmulti_link->cookies, ucount * sizeof(u64)))
2648 return -EFAULT;
2649 } else {
2650 for (i = 0; i < ucount; i++) {
2651 if (put_user(0, ucookies + i))
2652 return -EFAULT;
2657 if (kallsyms_show_value(current_cred())) {
2658 if (copy_to_user(uaddrs, kmulti_link->addrs, ucount * sizeof(u64)))
2659 return -EFAULT;
2660 } else {
2661 for (i = 0; i < ucount; i++) {
2662 if (put_user(0, uaddrs + i))
2663 return -EFAULT;
2666 return err;
2669 static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
2670 .release = bpf_kprobe_multi_link_release,
2671 .dealloc_deferred = bpf_kprobe_multi_link_dealloc,
2672 .fill_link_info = bpf_kprobe_multi_link_fill_link_info,
2675 static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
2677 const struct bpf_kprobe_multi_link *link = priv;
2678 unsigned long *addr_a = a, *addr_b = b;
2679 u64 *cookie_a, *cookie_b;
2681 cookie_a = link->cookies + (addr_a - link->addrs);
2682 cookie_b = link->cookies + (addr_b - link->addrs);
2684 /* swap addr_a/addr_b and cookie_a/cookie_b values */
2685 swap(*addr_a, *addr_b);
2686 swap(*cookie_a, *cookie_b);
2689 static int bpf_kprobe_multi_addrs_cmp(const void *a, const void *b)
2691 const unsigned long *addr_a = a, *addr_b = b;
2693 if (*addr_a == *addr_b)
2694 return 0;
2695 return *addr_a < *addr_b ? -1 : 1;
2698 static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
2700 return bpf_kprobe_multi_addrs_cmp(a, b);
2703 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2705 struct bpf_kprobe_multi_run_ctx *run_ctx;
2706 struct bpf_kprobe_multi_link *link;
2707 u64 *cookie, entry_ip;
2708 unsigned long *addr;
2710 if (WARN_ON_ONCE(!ctx))
2711 return 0;
2712 run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx,
2713 session_ctx.run_ctx);
2714 link = run_ctx->link;
2715 if (!link->cookies)
2716 return 0;
2717 entry_ip = run_ctx->entry_ip;
2718 addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
2719 bpf_kprobe_multi_addrs_cmp);
2720 if (!addr)
2721 return 0;
2722 cookie = link->cookies + (addr - link->addrs);
2723 return *cookie;
2726 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2728 struct bpf_kprobe_multi_run_ctx *run_ctx;
2730 run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx,
2731 session_ctx.run_ctx);
2732 return run_ctx->entry_ip;
2735 static int
2736 kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
2737 unsigned long entry_ip, struct pt_regs *regs,
2738 bool is_return, void *data)
2740 struct bpf_kprobe_multi_run_ctx run_ctx = {
2741 .session_ctx = {
2742 .is_return = is_return,
2743 .data = data,
2745 .link = link,
2746 .entry_ip = entry_ip,
2748 struct bpf_run_ctx *old_run_ctx;
2749 int err;
2751 if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
2752 bpf_prog_inc_misses_counter(link->link.prog);
2753 err = 0;
2754 goto out;
2757 migrate_disable();
2758 rcu_read_lock();
2759 old_run_ctx = bpf_set_run_ctx(&run_ctx.session_ctx.run_ctx);
2760 err = bpf_prog_run(link->link.prog, regs);
2761 bpf_reset_run_ctx(old_run_ctx);
2762 rcu_read_unlock();
2763 migrate_enable();
2765 out:
2766 __this_cpu_dec(bpf_prog_active);
2767 return err;
2770 static int
2771 kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
2772 unsigned long ret_ip, struct pt_regs *regs,
2773 void *data)
2775 struct bpf_kprobe_multi_link *link;
2776 int err;
2778 link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2779 err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false, data);
2780 return is_kprobe_session(link->link.prog) ? err : 0;
2783 static void
2784 kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip,
2785 unsigned long ret_ip, struct pt_regs *regs,
2786 void *data)
2788 struct bpf_kprobe_multi_link *link;
2790 link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2791 kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true, data);
2794 static int symbols_cmp_r(const void *a, const void *b, const void *priv)
2796 const char **str_a = (const char **) a;
2797 const char **str_b = (const char **) b;
2799 return strcmp(*str_a, *str_b);
2802 struct multi_symbols_sort {
2803 const char **funcs;
2804 u64 *cookies;
2807 static void symbols_swap_r(void *a, void *b, int size, const void *priv)
2809 const struct multi_symbols_sort *data = priv;
2810 const char **name_a = a, **name_b = b;
2812 swap(*name_a, *name_b);
2814 /* If defined, swap also related cookies. */
2815 if (data->cookies) {
2816 u64 *cookie_a, *cookie_b;
2818 cookie_a = data->cookies + (name_a - data->funcs);
2819 cookie_b = data->cookies + (name_b - data->funcs);
2820 swap(*cookie_a, *cookie_b);
2824 struct modules_array {
2825 struct module **mods;
2826 int mods_cnt;
2827 int mods_cap;
2830 static int add_module(struct modules_array *arr, struct module *mod)
2832 struct module **mods;
2834 if (arr->mods_cnt == arr->mods_cap) {
2835 arr->mods_cap = max(16, arr->mods_cap * 3 / 2);
2836 mods = krealloc_array(arr->mods, arr->mods_cap, sizeof(*mods), GFP_KERNEL);
2837 if (!mods)
2838 return -ENOMEM;
2839 arr->mods = mods;
2842 arr->mods[arr->mods_cnt] = mod;
2843 arr->mods_cnt++;
2844 return 0;
2847 static bool has_module(struct modules_array *arr, struct module *mod)
2849 int i;
2851 for (i = arr->mods_cnt - 1; i >= 0; i--) {
2852 if (arr->mods[i] == mod)
2853 return true;
2855 return false;
2858 static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u32 addrs_cnt)
2860 struct modules_array arr = {};
2861 u32 i, err = 0;
2863 for (i = 0; i < addrs_cnt; i++) {
2864 struct module *mod;
2866 preempt_disable();
2867 mod = __module_address(addrs[i]);
2868 /* Either no module or we it's already stored */
2869 if (!mod || has_module(&arr, mod)) {
2870 preempt_enable();
2871 continue;
2873 if (!try_module_get(mod))
2874 err = -EINVAL;
2875 preempt_enable();
2876 if (err)
2877 break;
2878 err = add_module(&arr, mod);
2879 if (err) {
2880 module_put(mod);
2881 break;
2885 /* We return either err < 0 in case of error, ... */
2886 if (err) {
2887 kprobe_multi_put_modules(arr.mods, arr.mods_cnt);
2888 kfree(arr.mods);
2889 return err;
2892 /* or number of modules found if everything is ok. */
2893 *mods = arr.mods;
2894 return arr.mods_cnt;
2897 static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt)
2899 u32 i;
2901 for (i = 0; i < cnt; i++) {
2902 if (!within_error_injection_list(addrs[i]))
2903 return -EINVAL;
2905 return 0;
2908 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2910 struct bpf_kprobe_multi_link *link = NULL;
2911 struct bpf_link_primer link_primer;
2912 void __user *ucookies;
2913 unsigned long *addrs;
2914 u32 flags, cnt, size;
2915 void __user *uaddrs;
2916 u64 *cookies = NULL;
2917 void __user *usyms;
2918 int err;
2920 /* no support for 32bit archs yet */
2921 if (sizeof(u64) != sizeof(void *))
2922 return -EOPNOTSUPP;
2924 if (!is_kprobe_multi(prog))
2925 return -EINVAL;
2927 flags = attr->link_create.kprobe_multi.flags;
2928 if (flags & ~BPF_F_KPROBE_MULTI_RETURN)
2929 return -EINVAL;
2931 uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs);
2932 usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms);
2933 if (!!uaddrs == !!usyms)
2934 return -EINVAL;
2936 cnt = attr->link_create.kprobe_multi.cnt;
2937 if (!cnt)
2938 return -EINVAL;
2939 if (cnt > MAX_KPROBE_MULTI_CNT)
2940 return -E2BIG;
2942 size = cnt * sizeof(*addrs);
2943 addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2944 if (!addrs)
2945 return -ENOMEM;
2947 ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
2948 if (ucookies) {
2949 cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2950 if (!cookies) {
2951 err = -ENOMEM;
2952 goto error;
2954 if (copy_from_user(cookies, ucookies, size)) {
2955 err = -EFAULT;
2956 goto error;
2960 if (uaddrs) {
2961 if (copy_from_user(addrs, uaddrs, size)) {
2962 err = -EFAULT;
2963 goto error;
2965 } else {
2966 struct multi_symbols_sort data = {
2967 .cookies = cookies,
2969 struct user_syms us;
2971 err = copy_user_syms(&us, usyms, cnt);
2972 if (err)
2973 goto error;
2975 if (cookies)
2976 data.funcs = us.syms;
2978 sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r,
2979 symbols_swap_r, &data);
2981 err = ftrace_lookup_symbols(us.syms, cnt, addrs);
2982 free_user_syms(&us);
2983 if (err)
2984 goto error;
2987 if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) {
2988 err = -EINVAL;
2989 goto error;
2992 link = kzalloc(sizeof(*link), GFP_KERNEL);
2993 if (!link) {
2994 err = -ENOMEM;
2995 goto error;
2998 bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI,
2999 &bpf_kprobe_multi_link_lops, prog);
3001 err = bpf_link_prime(&link->link, &link_primer);
3002 if (err)
3003 goto error;
3005 if (!(flags & BPF_F_KPROBE_MULTI_RETURN))
3006 link->fp.entry_handler = kprobe_multi_link_handler;
3007 if ((flags & BPF_F_KPROBE_MULTI_RETURN) || is_kprobe_session(prog))
3008 link->fp.exit_handler = kprobe_multi_link_exit_handler;
3009 if (is_kprobe_session(prog))
3010 link->fp.entry_data_size = sizeof(u64);
3012 link->addrs = addrs;
3013 link->cookies = cookies;
3014 link->cnt = cnt;
3015 link->flags = flags;
3017 if (cookies) {
3019 * Sorting addresses will trigger sorting cookies as well
3020 * (check bpf_kprobe_multi_cookie_swap). This way we can
3021 * find cookie based on the address in bpf_get_attach_cookie
3022 * helper.
3024 sort_r(addrs, cnt, sizeof(*addrs),
3025 bpf_kprobe_multi_cookie_cmp,
3026 bpf_kprobe_multi_cookie_swap,
3027 link);
3030 err = get_modules_for_addrs(&link->mods, addrs, cnt);
3031 if (err < 0) {
3032 bpf_link_cleanup(&link_primer);
3033 return err;
3035 link->mods_cnt = err;
3037 err = register_fprobe_ips(&link->fp, addrs, cnt);
3038 if (err) {
3039 kprobe_multi_put_modules(link->mods, link->mods_cnt);
3040 bpf_link_cleanup(&link_primer);
3041 return err;
3044 return bpf_link_settle(&link_primer);
3046 error:
3047 kfree(link);
3048 kvfree(addrs);
3049 kvfree(cookies);
3050 return err;
3052 #else /* !CONFIG_FPROBE */
3053 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3055 return -EOPNOTSUPP;
3057 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
3059 return 0;
3061 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3063 return 0;
3065 #endif
3067 #ifdef CONFIG_UPROBES
3068 struct bpf_uprobe_multi_link;
3070 struct bpf_uprobe {
3071 struct bpf_uprobe_multi_link *link;
3072 loff_t offset;
3073 unsigned long ref_ctr_offset;
3074 u64 cookie;
3075 struct uprobe *uprobe;
3076 struct uprobe_consumer consumer;
3079 struct bpf_uprobe_multi_link {
3080 struct path path;
3081 struct bpf_link link;
3082 u32 cnt;
3083 u32 flags;
3084 struct bpf_uprobe *uprobes;
3085 struct task_struct *task;
3088 struct bpf_uprobe_multi_run_ctx {
3089 struct bpf_run_ctx run_ctx;
3090 unsigned long entry_ip;
3091 struct bpf_uprobe *uprobe;
3094 static void bpf_uprobe_unregister(struct bpf_uprobe *uprobes, u32 cnt)
3096 u32 i;
3098 for (i = 0; i < cnt; i++)
3099 uprobe_unregister_nosync(uprobes[i].uprobe, &uprobes[i].consumer);
3101 if (cnt)
3102 uprobe_unregister_sync();
3105 static void bpf_uprobe_multi_link_release(struct bpf_link *link)
3107 struct bpf_uprobe_multi_link *umulti_link;
3109 umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3110 bpf_uprobe_unregister(umulti_link->uprobes, umulti_link->cnt);
3111 if (umulti_link->task)
3112 put_task_struct(umulti_link->task);
3113 path_put(&umulti_link->path);
3116 static void bpf_uprobe_multi_link_dealloc(struct bpf_link *link)
3118 struct bpf_uprobe_multi_link *umulti_link;
3120 umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3121 kvfree(umulti_link->uprobes);
3122 kfree(umulti_link);
3125 static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link,
3126 struct bpf_link_info *info)
3128 u64 __user *uref_ctr_offsets = u64_to_user_ptr(info->uprobe_multi.ref_ctr_offsets);
3129 u64 __user *ucookies = u64_to_user_ptr(info->uprobe_multi.cookies);
3130 u64 __user *uoffsets = u64_to_user_ptr(info->uprobe_multi.offsets);
3131 u64 __user *upath = u64_to_user_ptr(info->uprobe_multi.path);
3132 u32 upath_size = info->uprobe_multi.path_size;
3133 struct bpf_uprobe_multi_link *umulti_link;
3134 u32 ucount = info->uprobe_multi.count;
3135 int err = 0, i;
3136 char *p, *buf;
3137 long left = 0;
3139 if (!upath ^ !upath_size)
3140 return -EINVAL;
3142 if ((uoffsets || uref_ctr_offsets || ucookies) && !ucount)
3143 return -EINVAL;
3145 umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3146 info->uprobe_multi.count = umulti_link->cnt;
3147 info->uprobe_multi.flags = umulti_link->flags;
3148 info->uprobe_multi.pid = umulti_link->task ?
3149 task_pid_nr_ns(umulti_link->task, task_active_pid_ns(current)) : 0;
3151 upath_size = upath_size ? min_t(u32, upath_size, PATH_MAX) : PATH_MAX;
3152 buf = kmalloc(upath_size, GFP_KERNEL);
3153 if (!buf)
3154 return -ENOMEM;
3155 p = d_path(&umulti_link->path, buf, upath_size);
3156 if (IS_ERR(p)) {
3157 kfree(buf);
3158 return PTR_ERR(p);
3160 upath_size = buf + upath_size - p;
3162 if (upath)
3163 left = copy_to_user(upath, p, upath_size);
3164 kfree(buf);
3165 if (left)
3166 return -EFAULT;
3167 info->uprobe_multi.path_size = upath_size;
3169 if (!uoffsets && !ucookies && !uref_ctr_offsets)
3170 return 0;
3172 if (ucount < umulti_link->cnt)
3173 err = -ENOSPC;
3174 else
3175 ucount = umulti_link->cnt;
3177 for (i = 0; i < ucount; i++) {
3178 if (uoffsets &&
3179 put_user(umulti_link->uprobes[i].offset, uoffsets + i))
3180 return -EFAULT;
3181 if (uref_ctr_offsets &&
3182 put_user(umulti_link->uprobes[i].ref_ctr_offset, uref_ctr_offsets + i))
3183 return -EFAULT;
3184 if (ucookies &&
3185 put_user(umulti_link->uprobes[i].cookie, ucookies + i))
3186 return -EFAULT;
3189 return err;
3192 static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
3193 .release = bpf_uprobe_multi_link_release,
3194 .dealloc_deferred = bpf_uprobe_multi_link_dealloc,
3195 .fill_link_info = bpf_uprobe_multi_link_fill_link_info,
3198 static int uprobe_prog_run(struct bpf_uprobe *uprobe,
3199 unsigned long entry_ip,
3200 struct pt_regs *regs)
3202 struct bpf_uprobe_multi_link *link = uprobe->link;
3203 struct bpf_uprobe_multi_run_ctx run_ctx = {
3204 .entry_ip = entry_ip,
3205 .uprobe = uprobe,
3207 struct bpf_prog *prog = link->link.prog;
3208 bool sleepable = prog->sleepable;
3209 struct bpf_run_ctx *old_run_ctx;
3210 int err = 0;
3212 if (link->task && !same_thread_group(current, link->task))
3213 return 0;
3215 if (sleepable)
3216 rcu_read_lock_trace();
3217 else
3218 rcu_read_lock();
3220 migrate_disable();
3222 old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
3223 err = bpf_prog_run(link->link.prog, regs);
3224 bpf_reset_run_ctx(old_run_ctx);
3226 migrate_enable();
3228 if (sleepable)
3229 rcu_read_unlock_trace();
3230 else
3231 rcu_read_unlock();
3232 return err;
3235 static bool
3236 uprobe_multi_link_filter(struct uprobe_consumer *con, struct mm_struct *mm)
3238 struct bpf_uprobe *uprobe;
3240 uprobe = container_of(con, struct bpf_uprobe, consumer);
3241 return uprobe->link->task->mm == mm;
3244 static int
3245 uprobe_multi_link_handler(struct uprobe_consumer *con, struct pt_regs *regs)
3247 struct bpf_uprobe *uprobe;
3249 uprobe = container_of(con, struct bpf_uprobe, consumer);
3250 return uprobe_prog_run(uprobe, instruction_pointer(regs), regs);
3253 static int
3254 uprobe_multi_link_ret_handler(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs)
3256 struct bpf_uprobe *uprobe;
3258 uprobe = container_of(con, struct bpf_uprobe, consumer);
3259 return uprobe_prog_run(uprobe, func, regs);
3262 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3264 struct bpf_uprobe_multi_run_ctx *run_ctx;
3266 run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
3267 return run_ctx->entry_ip;
3270 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
3272 struct bpf_uprobe_multi_run_ctx *run_ctx;
3274 run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
3275 return run_ctx->uprobe->cookie;
3278 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3280 struct bpf_uprobe_multi_link *link = NULL;
3281 unsigned long __user *uref_ctr_offsets;
3282 struct bpf_link_primer link_primer;
3283 struct bpf_uprobe *uprobes = NULL;
3284 struct task_struct *task = NULL;
3285 unsigned long __user *uoffsets;
3286 u64 __user *ucookies;
3287 void __user *upath;
3288 u32 flags, cnt, i;
3289 struct path path;
3290 char *name;
3291 pid_t pid;
3292 int err;
3294 /* no support for 32bit archs yet */
3295 if (sizeof(u64) != sizeof(void *))
3296 return -EOPNOTSUPP;
3298 if (prog->expected_attach_type != BPF_TRACE_UPROBE_MULTI)
3299 return -EINVAL;
3301 flags = attr->link_create.uprobe_multi.flags;
3302 if (flags & ~BPF_F_UPROBE_MULTI_RETURN)
3303 return -EINVAL;
3306 * path, offsets and cnt are mandatory,
3307 * ref_ctr_offsets and cookies are optional
3309 upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path);
3310 uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets);
3311 cnt = attr->link_create.uprobe_multi.cnt;
3312 pid = attr->link_create.uprobe_multi.pid;
3314 if (!upath || !uoffsets || !cnt || pid < 0)
3315 return -EINVAL;
3316 if (cnt > MAX_UPROBE_MULTI_CNT)
3317 return -E2BIG;
3319 uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets);
3320 ucookies = u64_to_user_ptr(attr->link_create.uprobe_multi.cookies);
3322 name = strndup_user(upath, PATH_MAX);
3323 if (IS_ERR(name)) {
3324 err = PTR_ERR(name);
3325 return err;
3328 err = kern_path(name, LOOKUP_FOLLOW, &path);
3329 kfree(name);
3330 if (err)
3331 return err;
3333 if (!d_is_reg(path.dentry)) {
3334 err = -EBADF;
3335 goto error_path_put;
3338 if (pid) {
3339 task = get_pid_task(find_vpid(pid), PIDTYPE_TGID);
3340 if (!task) {
3341 err = -ESRCH;
3342 goto error_path_put;
3346 err = -ENOMEM;
3348 link = kzalloc(sizeof(*link), GFP_KERNEL);
3349 uprobes = kvcalloc(cnt, sizeof(*uprobes), GFP_KERNEL);
3351 if (!uprobes || !link)
3352 goto error_free;
3354 for (i = 0; i < cnt; i++) {
3355 if (__get_user(uprobes[i].offset, uoffsets + i)) {
3356 err = -EFAULT;
3357 goto error_free;
3359 if (uprobes[i].offset < 0) {
3360 err = -EINVAL;
3361 goto error_free;
3363 if (uref_ctr_offsets && __get_user(uprobes[i].ref_ctr_offset, uref_ctr_offsets + i)) {
3364 err = -EFAULT;
3365 goto error_free;
3367 if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) {
3368 err = -EFAULT;
3369 goto error_free;
3372 uprobes[i].link = link;
3374 if (flags & BPF_F_UPROBE_MULTI_RETURN)
3375 uprobes[i].consumer.ret_handler = uprobe_multi_link_ret_handler;
3376 else
3377 uprobes[i].consumer.handler = uprobe_multi_link_handler;
3379 if (pid)
3380 uprobes[i].consumer.filter = uprobe_multi_link_filter;
3383 link->cnt = cnt;
3384 link->uprobes = uprobes;
3385 link->path = path;
3386 link->task = task;
3387 link->flags = flags;
3389 bpf_link_init(&link->link, BPF_LINK_TYPE_UPROBE_MULTI,
3390 &bpf_uprobe_multi_link_lops, prog);
3392 for (i = 0; i < cnt; i++) {
3393 uprobes[i].uprobe = uprobe_register(d_real_inode(link->path.dentry),
3394 uprobes[i].offset,
3395 uprobes[i].ref_ctr_offset,
3396 &uprobes[i].consumer);
3397 if (IS_ERR(uprobes[i].uprobe)) {
3398 err = PTR_ERR(uprobes[i].uprobe);
3399 link->cnt = i;
3400 goto error_unregister;
3404 err = bpf_link_prime(&link->link, &link_primer);
3405 if (err)
3406 goto error_unregister;
3408 return bpf_link_settle(&link_primer);
3410 error_unregister:
3411 bpf_uprobe_unregister(uprobes, link->cnt);
3413 error_free:
3414 kvfree(uprobes);
3415 kfree(link);
3416 if (task)
3417 put_task_struct(task);
3418 error_path_put:
3419 path_put(&path);
3420 return err;
3422 #else /* !CONFIG_UPROBES */
3423 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3425 return -EOPNOTSUPP;
3427 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
3429 return 0;
3431 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3433 return 0;
3435 #endif /* CONFIG_UPROBES */
3437 __bpf_kfunc_start_defs();
3439 __bpf_kfunc bool bpf_session_is_return(void)
3441 struct bpf_session_run_ctx *session_ctx;
3443 session_ctx = container_of(current->bpf_ctx, struct bpf_session_run_ctx, run_ctx);
3444 return session_ctx->is_return;
3447 __bpf_kfunc __u64 *bpf_session_cookie(void)
3449 struct bpf_session_run_ctx *session_ctx;
3451 session_ctx = container_of(current->bpf_ctx, struct bpf_session_run_ctx, run_ctx);
3452 return session_ctx->data;
3455 __bpf_kfunc_end_defs();
3457 BTF_KFUNCS_START(kprobe_multi_kfunc_set_ids)
3458 BTF_ID_FLAGS(func, bpf_session_is_return)
3459 BTF_ID_FLAGS(func, bpf_session_cookie)
3460 BTF_KFUNCS_END(kprobe_multi_kfunc_set_ids)
3462 static int bpf_kprobe_multi_filter(const struct bpf_prog *prog, u32 kfunc_id)
3464 if (!btf_id_set8_contains(&kprobe_multi_kfunc_set_ids, kfunc_id))
3465 return 0;
3467 if (!is_kprobe_session(prog))
3468 return -EACCES;
3470 return 0;
3473 static const struct btf_kfunc_id_set bpf_kprobe_multi_kfunc_set = {
3474 .owner = THIS_MODULE,
3475 .set = &kprobe_multi_kfunc_set_ids,
3476 .filter = bpf_kprobe_multi_filter,
3479 static int __init bpf_kprobe_multi_kfuncs_init(void)
3481 return register_btf_kfunc_id_set(BPF_PROG_TYPE_KPROBE, &bpf_kprobe_multi_kfunc_set);
3484 late_initcall(bpf_kprobe_multi_kfuncs_init);