xref: /linux-6.15/kernel/trace/bpf_trace.c (revision 41f6f64e)
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>
27 #include <linux/fileattr.h>
28 
29 #include <net/bpf_sk_storage.h>
30 
31 #include <uapi/linux/bpf.h>
32 #include <uapi/linux/btf.h>
33 
34 #include <asm/tlb.h>
35 
36 #include "trace_probe.h"
37 #include "trace.h"
38 
39 #define CREATE_TRACE_POINTS
40 #include "bpf_trace.h"
41 
42 #define bpf_event_rcu_dereference(p)					\
43 	rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
44 
45 #ifdef CONFIG_MODULES
46 struct bpf_trace_module {
47 	struct module *module;
48 	struct list_head list;
49 };
50 
51 static LIST_HEAD(bpf_trace_modules);
52 static DEFINE_MUTEX(bpf_module_mutex);
53 
54 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
55 {
56 	struct bpf_raw_event_map *btp, *ret = NULL;
57 	struct bpf_trace_module *btm;
58 	unsigned int i;
59 
60 	mutex_lock(&bpf_module_mutex);
61 	list_for_each_entry(btm, &bpf_trace_modules, list) {
62 		for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
63 			btp = &btm->module->bpf_raw_events[i];
64 			if (!strcmp(btp->tp->name, name)) {
65 				if (try_module_get(btm->module))
66 					ret = btp;
67 				goto out;
68 			}
69 		}
70 	}
71 out:
72 	mutex_unlock(&bpf_module_mutex);
73 	return ret;
74 }
75 #else
76 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
77 {
78 	return NULL;
79 }
80 #endif /* CONFIG_MODULES */
81 
82 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
83 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
84 
85 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
86 				  u64 flags, const struct btf **btf,
87 				  s32 *btf_id);
88 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
89 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
90 
91 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx);
92 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
93 
94 /**
95  * trace_call_bpf - invoke BPF program
96  * @call: tracepoint event
97  * @ctx: opaque context pointer
98  *
99  * kprobe handlers execute BPF programs via this helper.
100  * Can be used from static tracepoints in the future.
101  *
102  * Return: BPF programs always return an integer which is interpreted by
103  * kprobe handler as:
104  * 0 - return from kprobe (event is filtered out)
105  * 1 - store kprobe event into ring buffer
106  * Other values are reserved and currently alias to 1
107  */
108 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
109 {
110 	unsigned int ret;
111 
112 	cant_sleep();
113 
114 	if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
115 		/*
116 		 * since some bpf program is already running on this cpu,
117 		 * don't call into another bpf program (same or different)
118 		 * and don't send kprobe event into ring-buffer,
119 		 * so return zero here
120 		 */
121 		rcu_read_lock();
122 		bpf_prog_inc_misses_counters(rcu_dereference(call->prog_array));
123 		rcu_read_unlock();
124 		ret = 0;
125 		goto out;
126 	}
127 
128 	/*
129 	 * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
130 	 * to all call sites, we did a bpf_prog_array_valid() there to check
131 	 * whether call->prog_array is empty or not, which is
132 	 * a heuristic to speed up execution.
133 	 *
134 	 * If bpf_prog_array_valid() fetched prog_array was
135 	 * non-NULL, we go into trace_call_bpf() and do the actual
136 	 * proper rcu_dereference() under RCU lock.
137 	 * If it turns out that prog_array is NULL then, we bail out.
138 	 * For the opposite, if the bpf_prog_array_valid() fetched pointer
139 	 * was NULL, you'll skip the prog_array with the risk of missing
140 	 * out of events when it was updated in between this and the
141 	 * rcu_dereference() which is accepted risk.
142 	 */
143 	rcu_read_lock();
144 	ret = bpf_prog_run_array(rcu_dereference(call->prog_array),
145 				 ctx, bpf_prog_run);
146 	rcu_read_unlock();
147 
148  out:
149 	__this_cpu_dec(bpf_prog_active);
150 
151 	return ret;
152 }
153 
154 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
155 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
156 {
157 	regs_set_return_value(regs, rc);
158 	override_function_with_return(regs);
159 	return 0;
160 }
161 
162 static const struct bpf_func_proto bpf_override_return_proto = {
163 	.func		= bpf_override_return,
164 	.gpl_only	= true,
165 	.ret_type	= RET_INTEGER,
166 	.arg1_type	= ARG_PTR_TO_CTX,
167 	.arg2_type	= ARG_ANYTHING,
168 };
169 #endif
170 
171 static __always_inline int
172 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
173 {
174 	int ret;
175 
176 	ret = copy_from_user_nofault(dst, unsafe_ptr, size);
177 	if (unlikely(ret < 0))
178 		memset(dst, 0, size);
179 	return ret;
180 }
181 
182 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
183 	   const void __user *, unsafe_ptr)
184 {
185 	return bpf_probe_read_user_common(dst, size, unsafe_ptr);
186 }
187 
188 const struct bpf_func_proto bpf_probe_read_user_proto = {
189 	.func		= bpf_probe_read_user,
190 	.gpl_only	= true,
191 	.ret_type	= RET_INTEGER,
192 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
193 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
194 	.arg3_type	= ARG_ANYTHING,
195 };
196 
197 static __always_inline int
198 bpf_probe_read_user_str_common(void *dst, u32 size,
199 			       const void __user *unsafe_ptr)
200 {
201 	int ret;
202 
203 	/*
204 	 * NB: We rely on strncpy_from_user() not copying junk past the NUL
205 	 * terminator into `dst`.
206 	 *
207 	 * strncpy_from_user() does long-sized strides in the fast path. If the
208 	 * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
209 	 * then there could be junk after the NUL in `dst`. If user takes `dst`
210 	 * and keys a hash map with it, then semantically identical strings can
211 	 * occupy multiple entries in the map.
212 	 */
213 	ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
214 	if (unlikely(ret < 0))
215 		memset(dst, 0, size);
216 	return ret;
217 }
218 
219 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
220 	   const void __user *, unsafe_ptr)
221 {
222 	return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
223 }
224 
225 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
226 	.func		= bpf_probe_read_user_str,
227 	.gpl_only	= true,
228 	.ret_type	= RET_INTEGER,
229 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
230 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
231 	.arg3_type	= ARG_ANYTHING,
232 };
233 
234 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
235 	   const void *, unsafe_ptr)
236 {
237 	return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
238 }
239 
240 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
241 	.func		= bpf_probe_read_kernel,
242 	.gpl_only	= true,
243 	.ret_type	= RET_INTEGER,
244 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
245 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
246 	.arg3_type	= ARG_ANYTHING,
247 };
248 
249 static __always_inline int
250 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
251 {
252 	int ret;
253 
254 	/*
255 	 * The strncpy_from_kernel_nofault() call will likely not fill the
256 	 * entire buffer, but that's okay in this circumstance as we're probing
257 	 * arbitrary memory anyway similar to bpf_probe_read_*() and might
258 	 * as well probe the stack. Thus, memory is explicitly cleared
259 	 * only in error case, so that improper users ignoring return
260 	 * code altogether don't copy garbage; otherwise length of string
261 	 * is returned that can be used for bpf_perf_event_output() et al.
262 	 */
263 	ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
264 	if (unlikely(ret < 0))
265 		memset(dst, 0, size);
266 	return ret;
267 }
268 
269 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
270 	   const void *, unsafe_ptr)
271 {
272 	return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
273 }
274 
275 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
276 	.func		= bpf_probe_read_kernel_str,
277 	.gpl_only	= true,
278 	.ret_type	= RET_INTEGER,
279 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
280 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
281 	.arg3_type	= ARG_ANYTHING,
282 };
283 
284 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
285 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
286 	   const void *, unsafe_ptr)
287 {
288 	if ((unsigned long)unsafe_ptr < TASK_SIZE) {
289 		return bpf_probe_read_user_common(dst, size,
290 				(__force void __user *)unsafe_ptr);
291 	}
292 	return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
293 }
294 
295 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
296 	.func		= bpf_probe_read_compat,
297 	.gpl_only	= true,
298 	.ret_type	= RET_INTEGER,
299 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
300 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
301 	.arg3_type	= ARG_ANYTHING,
302 };
303 
304 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
305 	   const void *, unsafe_ptr)
306 {
307 	if ((unsigned long)unsafe_ptr < TASK_SIZE) {
308 		return bpf_probe_read_user_str_common(dst, size,
309 				(__force void __user *)unsafe_ptr);
310 	}
311 	return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
312 }
313 
314 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
315 	.func		= bpf_probe_read_compat_str,
316 	.gpl_only	= true,
317 	.ret_type	= RET_INTEGER,
318 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
319 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
320 	.arg3_type	= ARG_ANYTHING,
321 };
322 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
323 
324 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
325 	   u32, size)
326 {
327 	/*
328 	 * Ensure we're in user context which is safe for the helper to
329 	 * run. This helper has no business in a kthread.
330 	 *
331 	 * access_ok() should prevent writing to non-user memory, but in
332 	 * some situations (nommu, temporary switch, etc) access_ok() does
333 	 * not provide enough validation, hence the check on KERNEL_DS.
334 	 *
335 	 * nmi_uaccess_okay() ensures the probe is not run in an interim
336 	 * state, when the task or mm are switched. This is specifically
337 	 * required to prevent the use of temporary mm.
338 	 */
339 
340 	if (unlikely(in_interrupt() ||
341 		     current->flags & (PF_KTHREAD | PF_EXITING)))
342 		return -EPERM;
343 	if (unlikely(!nmi_uaccess_okay()))
344 		return -EPERM;
345 
346 	return copy_to_user_nofault(unsafe_ptr, src, size);
347 }
348 
349 static const struct bpf_func_proto bpf_probe_write_user_proto = {
350 	.func		= bpf_probe_write_user,
351 	.gpl_only	= true,
352 	.ret_type	= RET_INTEGER,
353 	.arg1_type	= ARG_ANYTHING,
354 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
355 	.arg3_type	= ARG_CONST_SIZE,
356 };
357 
358 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
359 {
360 	if (!capable(CAP_SYS_ADMIN))
361 		return NULL;
362 
363 	pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
364 			    current->comm, task_pid_nr(current));
365 
366 	return &bpf_probe_write_user_proto;
367 }
368 
369 #define MAX_TRACE_PRINTK_VARARGS	3
370 #define BPF_TRACE_PRINTK_SIZE		1024
371 
372 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
373 	   u64, arg2, u64, arg3)
374 {
375 	u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
376 	struct bpf_bprintf_data data = {
377 		.get_bin_args	= true,
378 		.get_buf	= true,
379 	};
380 	int ret;
381 
382 	ret = bpf_bprintf_prepare(fmt, fmt_size, args,
383 				  MAX_TRACE_PRINTK_VARARGS, &data);
384 	if (ret < 0)
385 		return ret;
386 
387 	ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
388 
389 	trace_bpf_trace_printk(data.buf);
390 
391 	bpf_bprintf_cleanup(&data);
392 
393 	return ret;
394 }
395 
396 static const struct bpf_func_proto bpf_trace_printk_proto = {
397 	.func		= bpf_trace_printk,
398 	.gpl_only	= true,
399 	.ret_type	= RET_INTEGER,
400 	.arg1_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
401 	.arg2_type	= ARG_CONST_SIZE,
402 };
403 
404 static void __set_printk_clr_event(void)
405 {
406 	/*
407 	 * This program might be calling bpf_trace_printk,
408 	 * so enable the associated bpf_trace/bpf_trace_printk event.
409 	 * Repeat this each time as it is possible a user has
410 	 * disabled bpf_trace_printk events.  By loading a program
411 	 * calling bpf_trace_printk() however the user has expressed
412 	 * the intent to see such events.
413 	 */
414 	if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
415 		pr_warn_ratelimited("could not enable bpf_trace_printk events");
416 }
417 
418 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
419 {
420 	__set_printk_clr_event();
421 	return &bpf_trace_printk_proto;
422 }
423 
424 BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, args,
425 	   u32, data_len)
426 {
427 	struct bpf_bprintf_data data = {
428 		.get_bin_args	= true,
429 		.get_buf	= true,
430 	};
431 	int ret, num_args;
432 
433 	if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
434 	    (data_len && !args))
435 		return -EINVAL;
436 	num_args = data_len / 8;
437 
438 	ret = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
439 	if (ret < 0)
440 		return ret;
441 
442 	ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
443 
444 	trace_bpf_trace_printk(data.buf);
445 
446 	bpf_bprintf_cleanup(&data);
447 
448 	return ret;
449 }
450 
451 static const struct bpf_func_proto bpf_trace_vprintk_proto = {
452 	.func		= bpf_trace_vprintk,
453 	.gpl_only	= true,
454 	.ret_type	= RET_INTEGER,
455 	.arg1_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
456 	.arg2_type	= ARG_CONST_SIZE,
457 	.arg3_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
458 	.arg4_type	= ARG_CONST_SIZE_OR_ZERO,
459 };
460 
461 const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
462 {
463 	__set_printk_clr_event();
464 	return &bpf_trace_vprintk_proto;
465 }
466 
467 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
468 	   const void *, args, u32, data_len)
469 {
470 	struct bpf_bprintf_data data = {
471 		.get_bin_args	= true,
472 	};
473 	int err, num_args;
474 
475 	if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
476 	    (data_len && !args))
477 		return -EINVAL;
478 	num_args = data_len / 8;
479 
480 	err = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data);
481 	if (err < 0)
482 		return err;
483 
484 	seq_bprintf(m, fmt, data.bin_args);
485 
486 	bpf_bprintf_cleanup(&data);
487 
488 	return seq_has_overflowed(m) ? -EOVERFLOW : 0;
489 }
490 
491 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
492 
493 static const struct bpf_func_proto bpf_seq_printf_proto = {
494 	.func		= bpf_seq_printf,
495 	.gpl_only	= true,
496 	.ret_type	= RET_INTEGER,
497 	.arg1_type	= ARG_PTR_TO_BTF_ID,
498 	.arg1_btf_id	= &btf_seq_file_ids[0],
499 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
500 	.arg3_type	= ARG_CONST_SIZE,
501 	.arg4_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
502 	.arg5_type      = ARG_CONST_SIZE_OR_ZERO,
503 };
504 
505 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
506 {
507 	return seq_write(m, data, len) ? -EOVERFLOW : 0;
508 }
509 
510 static const struct bpf_func_proto bpf_seq_write_proto = {
511 	.func		= bpf_seq_write,
512 	.gpl_only	= true,
513 	.ret_type	= RET_INTEGER,
514 	.arg1_type	= ARG_PTR_TO_BTF_ID,
515 	.arg1_btf_id	= &btf_seq_file_ids[0],
516 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
517 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
518 };
519 
520 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
521 	   u32, btf_ptr_size, u64, flags)
522 {
523 	const struct btf *btf;
524 	s32 btf_id;
525 	int ret;
526 
527 	ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
528 	if (ret)
529 		return ret;
530 
531 	return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
532 }
533 
534 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
535 	.func		= bpf_seq_printf_btf,
536 	.gpl_only	= true,
537 	.ret_type	= RET_INTEGER,
538 	.arg1_type	= ARG_PTR_TO_BTF_ID,
539 	.arg1_btf_id	= &btf_seq_file_ids[0],
540 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
541 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
542 	.arg4_type	= ARG_ANYTHING,
543 };
544 
545 static __always_inline int
546 get_map_perf_counter(struct bpf_map *map, u64 flags,
547 		     u64 *value, u64 *enabled, u64 *running)
548 {
549 	struct bpf_array *array = container_of(map, struct bpf_array, map);
550 	unsigned int cpu = smp_processor_id();
551 	u64 index = flags & BPF_F_INDEX_MASK;
552 	struct bpf_event_entry *ee;
553 
554 	if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
555 		return -EINVAL;
556 	if (index == BPF_F_CURRENT_CPU)
557 		index = cpu;
558 	if (unlikely(index >= array->map.max_entries))
559 		return -E2BIG;
560 
561 	ee = READ_ONCE(array->ptrs[index]);
562 	if (!ee)
563 		return -ENOENT;
564 
565 	return perf_event_read_local(ee->event, value, enabled, running);
566 }
567 
568 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
569 {
570 	u64 value = 0;
571 	int err;
572 
573 	err = get_map_perf_counter(map, flags, &value, NULL, NULL);
574 	/*
575 	 * this api is ugly since we miss [-22..-2] range of valid
576 	 * counter values, but that's uapi
577 	 */
578 	if (err)
579 		return err;
580 	return value;
581 }
582 
583 static const struct bpf_func_proto bpf_perf_event_read_proto = {
584 	.func		= bpf_perf_event_read,
585 	.gpl_only	= true,
586 	.ret_type	= RET_INTEGER,
587 	.arg1_type	= ARG_CONST_MAP_PTR,
588 	.arg2_type	= ARG_ANYTHING,
589 };
590 
591 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
592 	   struct bpf_perf_event_value *, buf, u32, size)
593 {
594 	int err = -EINVAL;
595 
596 	if (unlikely(size != sizeof(struct bpf_perf_event_value)))
597 		goto clear;
598 	err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
599 				   &buf->running);
600 	if (unlikely(err))
601 		goto clear;
602 	return 0;
603 clear:
604 	memset(buf, 0, size);
605 	return err;
606 }
607 
608 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
609 	.func		= bpf_perf_event_read_value,
610 	.gpl_only	= true,
611 	.ret_type	= RET_INTEGER,
612 	.arg1_type	= ARG_CONST_MAP_PTR,
613 	.arg2_type	= ARG_ANYTHING,
614 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
615 	.arg4_type	= ARG_CONST_SIZE,
616 };
617 
618 static __always_inline u64
619 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
620 			u64 flags, struct perf_sample_data *sd)
621 {
622 	struct bpf_array *array = container_of(map, struct bpf_array, map);
623 	unsigned int cpu = smp_processor_id();
624 	u64 index = flags & BPF_F_INDEX_MASK;
625 	struct bpf_event_entry *ee;
626 	struct perf_event *event;
627 
628 	if (index == BPF_F_CURRENT_CPU)
629 		index = cpu;
630 	if (unlikely(index >= array->map.max_entries))
631 		return -E2BIG;
632 
633 	ee = READ_ONCE(array->ptrs[index]);
634 	if (!ee)
635 		return -ENOENT;
636 
637 	event = ee->event;
638 	if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
639 		     event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
640 		return -EINVAL;
641 
642 	if (unlikely(event->oncpu != cpu))
643 		return -EOPNOTSUPP;
644 
645 	return perf_event_output(event, sd, regs);
646 }
647 
648 /*
649  * Support executing tracepoints in normal, irq, and nmi context that each call
650  * bpf_perf_event_output
651  */
652 struct bpf_trace_sample_data {
653 	struct perf_sample_data sds[3];
654 };
655 
656 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
657 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
658 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
659 	   u64, flags, void *, data, u64, size)
660 {
661 	struct bpf_trace_sample_data *sds;
662 	struct perf_raw_record raw = {
663 		.frag = {
664 			.size = size,
665 			.data = data,
666 		},
667 	};
668 	struct perf_sample_data *sd;
669 	int nest_level, err;
670 
671 	preempt_disable();
672 	sds = this_cpu_ptr(&bpf_trace_sds);
673 	nest_level = this_cpu_inc_return(bpf_trace_nest_level);
674 
675 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
676 		err = -EBUSY;
677 		goto out;
678 	}
679 
680 	sd = &sds->sds[nest_level - 1];
681 
682 	if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
683 		err = -EINVAL;
684 		goto out;
685 	}
686 
687 	perf_sample_data_init(sd, 0, 0);
688 	perf_sample_save_raw_data(sd, &raw);
689 
690 	err = __bpf_perf_event_output(regs, map, flags, sd);
691 out:
692 	this_cpu_dec(bpf_trace_nest_level);
693 	preempt_enable();
694 	return err;
695 }
696 
697 static const struct bpf_func_proto bpf_perf_event_output_proto = {
698 	.func		= bpf_perf_event_output,
699 	.gpl_only	= true,
700 	.ret_type	= RET_INTEGER,
701 	.arg1_type	= ARG_PTR_TO_CTX,
702 	.arg2_type	= ARG_CONST_MAP_PTR,
703 	.arg3_type	= ARG_ANYTHING,
704 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
705 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
706 };
707 
708 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
709 struct bpf_nested_pt_regs {
710 	struct pt_regs regs[3];
711 };
712 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
713 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
714 
715 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
716 		     void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
717 {
718 	struct perf_raw_frag frag = {
719 		.copy		= ctx_copy,
720 		.size		= ctx_size,
721 		.data		= ctx,
722 	};
723 	struct perf_raw_record raw = {
724 		.frag = {
725 			{
726 				.next	= ctx_size ? &frag : NULL,
727 			},
728 			.size	= meta_size,
729 			.data	= meta,
730 		},
731 	};
732 	struct perf_sample_data *sd;
733 	struct pt_regs *regs;
734 	int nest_level;
735 	u64 ret;
736 
737 	preempt_disable();
738 	nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
739 
740 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
741 		ret = -EBUSY;
742 		goto out;
743 	}
744 	sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
745 	regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
746 
747 	perf_fetch_caller_regs(regs);
748 	perf_sample_data_init(sd, 0, 0);
749 	perf_sample_save_raw_data(sd, &raw);
750 
751 	ret = __bpf_perf_event_output(regs, map, flags, sd);
752 out:
753 	this_cpu_dec(bpf_event_output_nest_level);
754 	preempt_enable();
755 	return ret;
756 }
757 
758 BPF_CALL_0(bpf_get_current_task)
759 {
760 	return (long) current;
761 }
762 
763 const struct bpf_func_proto bpf_get_current_task_proto = {
764 	.func		= bpf_get_current_task,
765 	.gpl_only	= true,
766 	.ret_type	= RET_INTEGER,
767 };
768 
769 BPF_CALL_0(bpf_get_current_task_btf)
770 {
771 	return (unsigned long) current;
772 }
773 
774 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
775 	.func		= bpf_get_current_task_btf,
776 	.gpl_only	= true,
777 	.ret_type	= RET_PTR_TO_BTF_ID_TRUSTED,
778 	.ret_btf_id	= &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
779 };
780 
781 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
782 {
783 	return (unsigned long) task_pt_regs(task);
784 }
785 
786 BTF_ID_LIST(bpf_task_pt_regs_ids)
787 BTF_ID(struct, pt_regs)
788 
789 const struct bpf_func_proto bpf_task_pt_regs_proto = {
790 	.func		= bpf_task_pt_regs,
791 	.gpl_only	= true,
792 	.arg1_type	= ARG_PTR_TO_BTF_ID,
793 	.arg1_btf_id	= &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
794 	.ret_type	= RET_PTR_TO_BTF_ID,
795 	.ret_btf_id	= &bpf_task_pt_regs_ids[0],
796 };
797 
798 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
799 {
800 	struct bpf_array *array = container_of(map, struct bpf_array, map);
801 	struct cgroup *cgrp;
802 
803 	if (unlikely(idx >= array->map.max_entries))
804 		return -E2BIG;
805 
806 	cgrp = READ_ONCE(array->ptrs[idx]);
807 	if (unlikely(!cgrp))
808 		return -EAGAIN;
809 
810 	return task_under_cgroup_hierarchy(current, cgrp);
811 }
812 
813 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
814 	.func           = bpf_current_task_under_cgroup,
815 	.gpl_only       = false,
816 	.ret_type       = RET_INTEGER,
817 	.arg1_type      = ARG_CONST_MAP_PTR,
818 	.arg2_type      = ARG_ANYTHING,
819 };
820 
821 struct send_signal_irq_work {
822 	struct irq_work irq_work;
823 	struct task_struct *task;
824 	u32 sig;
825 	enum pid_type type;
826 };
827 
828 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
829 
830 static void do_bpf_send_signal(struct irq_work *entry)
831 {
832 	struct send_signal_irq_work *work;
833 
834 	work = container_of(entry, struct send_signal_irq_work, irq_work);
835 	group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
836 	put_task_struct(work->task);
837 }
838 
839 static int bpf_send_signal_common(u32 sig, enum pid_type type)
840 {
841 	struct send_signal_irq_work *work = NULL;
842 
843 	/* Similar to bpf_probe_write_user, task needs to be
844 	 * in a sound condition and kernel memory access be
845 	 * permitted in order to send signal to the current
846 	 * task.
847 	 */
848 	if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
849 		return -EPERM;
850 	if (unlikely(!nmi_uaccess_okay()))
851 		return -EPERM;
852 	/* Task should not be pid=1 to avoid kernel panic. */
853 	if (unlikely(is_global_init(current)))
854 		return -EPERM;
855 
856 	if (irqs_disabled()) {
857 		/* Do an early check on signal validity. Otherwise,
858 		 * the error is lost in deferred irq_work.
859 		 */
860 		if (unlikely(!valid_signal(sig)))
861 			return -EINVAL;
862 
863 		work = this_cpu_ptr(&send_signal_work);
864 		if (irq_work_is_busy(&work->irq_work))
865 			return -EBUSY;
866 
867 		/* Add the current task, which is the target of sending signal,
868 		 * to the irq_work. The current task may change when queued
869 		 * irq works get executed.
870 		 */
871 		work->task = get_task_struct(current);
872 		work->sig = sig;
873 		work->type = type;
874 		irq_work_queue(&work->irq_work);
875 		return 0;
876 	}
877 
878 	return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
879 }
880 
881 BPF_CALL_1(bpf_send_signal, u32, sig)
882 {
883 	return bpf_send_signal_common(sig, PIDTYPE_TGID);
884 }
885 
886 static const struct bpf_func_proto bpf_send_signal_proto = {
887 	.func		= bpf_send_signal,
888 	.gpl_only	= false,
889 	.ret_type	= RET_INTEGER,
890 	.arg1_type	= ARG_ANYTHING,
891 };
892 
893 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
894 {
895 	return bpf_send_signal_common(sig, PIDTYPE_PID);
896 }
897 
898 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
899 	.func		= bpf_send_signal_thread,
900 	.gpl_only	= false,
901 	.ret_type	= RET_INTEGER,
902 	.arg1_type	= ARG_ANYTHING,
903 };
904 
905 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
906 {
907 	struct path copy;
908 	long len;
909 	char *p;
910 
911 	if (!sz)
912 		return 0;
913 
914 	/*
915 	 * The path pointer is verified as trusted and safe to use,
916 	 * but let's double check it's valid anyway to workaround
917 	 * potentially broken verifier.
918 	 */
919 	len = copy_from_kernel_nofault(&copy, path, sizeof(*path));
920 	if (len < 0)
921 		return len;
922 
923 	p = d_path(&copy, buf, sz);
924 	if (IS_ERR(p)) {
925 		len = PTR_ERR(p);
926 	} else {
927 		len = buf + sz - p;
928 		memmove(buf, p, len);
929 	}
930 
931 	return len;
932 }
933 
934 BTF_SET_START(btf_allowlist_d_path)
935 #ifdef CONFIG_SECURITY
936 BTF_ID(func, security_file_permission)
937 BTF_ID(func, security_inode_getattr)
938 BTF_ID(func, security_file_open)
939 #endif
940 #ifdef CONFIG_SECURITY_PATH
941 BTF_ID(func, security_path_truncate)
942 #endif
943 BTF_ID(func, vfs_truncate)
944 BTF_ID(func, vfs_fallocate)
945 BTF_ID(func, dentry_open)
946 BTF_ID(func, vfs_getattr)
947 BTF_ID(func, filp_close)
948 BTF_SET_END(btf_allowlist_d_path)
949 
950 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
951 {
952 	if (prog->type == BPF_PROG_TYPE_TRACING &&
953 	    prog->expected_attach_type == BPF_TRACE_ITER)
954 		return true;
955 
956 	if (prog->type == BPF_PROG_TYPE_LSM)
957 		return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
958 
959 	return btf_id_set_contains(&btf_allowlist_d_path,
960 				   prog->aux->attach_btf_id);
961 }
962 
963 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
964 
965 static const struct bpf_func_proto bpf_d_path_proto = {
966 	.func		= bpf_d_path,
967 	.gpl_only	= false,
968 	.ret_type	= RET_INTEGER,
969 	.arg1_type	= ARG_PTR_TO_BTF_ID,
970 	.arg1_btf_id	= &bpf_d_path_btf_ids[0],
971 	.arg2_type	= ARG_PTR_TO_MEM,
972 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
973 	.allowed	= bpf_d_path_allowed,
974 };
975 
976 #define BTF_F_ALL	(BTF_F_COMPACT  | BTF_F_NONAME | \
977 			 BTF_F_PTR_RAW | BTF_F_ZERO)
978 
979 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
980 				  u64 flags, const struct btf **btf,
981 				  s32 *btf_id)
982 {
983 	const struct btf_type *t;
984 
985 	if (unlikely(flags & ~(BTF_F_ALL)))
986 		return -EINVAL;
987 
988 	if (btf_ptr_size != sizeof(struct btf_ptr))
989 		return -EINVAL;
990 
991 	*btf = bpf_get_btf_vmlinux();
992 
993 	if (IS_ERR_OR_NULL(*btf))
994 		return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
995 
996 	if (ptr->type_id > 0)
997 		*btf_id = ptr->type_id;
998 	else
999 		return -EINVAL;
1000 
1001 	if (*btf_id > 0)
1002 		t = btf_type_by_id(*btf, *btf_id);
1003 	if (*btf_id <= 0 || !t)
1004 		return -ENOENT;
1005 
1006 	return 0;
1007 }
1008 
1009 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
1010 	   u32, btf_ptr_size, u64, flags)
1011 {
1012 	const struct btf *btf;
1013 	s32 btf_id;
1014 	int ret;
1015 
1016 	ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
1017 	if (ret)
1018 		return ret;
1019 
1020 	return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
1021 				      flags);
1022 }
1023 
1024 const struct bpf_func_proto bpf_snprintf_btf_proto = {
1025 	.func		= bpf_snprintf_btf,
1026 	.gpl_only	= false,
1027 	.ret_type	= RET_INTEGER,
1028 	.arg1_type	= ARG_PTR_TO_MEM,
1029 	.arg2_type	= ARG_CONST_SIZE,
1030 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1031 	.arg4_type	= ARG_CONST_SIZE,
1032 	.arg5_type	= ARG_ANYTHING,
1033 };
1034 
1035 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
1036 {
1037 	/* This helper call is inlined by verifier. */
1038 	return ((u64 *)ctx)[-2];
1039 }
1040 
1041 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
1042 	.func		= bpf_get_func_ip_tracing,
1043 	.gpl_only	= true,
1044 	.ret_type	= RET_INTEGER,
1045 	.arg1_type	= ARG_PTR_TO_CTX,
1046 };
1047 
1048 #ifdef CONFIG_X86_KERNEL_IBT
1049 static unsigned long get_entry_ip(unsigned long fentry_ip)
1050 {
1051 	u32 instr;
1052 
1053 	/* Being extra safe in here in case entry ip is on the page-edge. */
1054 	if (get_kernel_nofault(instr, (u32 *) fentry_ip - 1))
1055 		return fentry_ip;
1056 	if (is_endbr(instr))
1057 		fentry_ip -= ENDBR_INSN_SIZE;
1058 	return fentry_ip;
1059 }
1060 #else
1061 #define get_entry_ip(fentry_ip) fentry_ip
1062 #endif
1063 
1064 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
1065 {
1066 	struct bpf_trace_run_ctx *run_ctx __maybe_unused;
1067 	struct kprobe *kp;
1068 
1069 #ifdef CONFIG_UPROBES
1070 	run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1071 	if (run_ctx->is_uprobe)
1072 		return ((struct uprobe_dispatch_data *)current->utask->vaddr)->bp_addr;
1073 #endif
1074 
1075 	kp = kprobe_running();
1076 
1077 	if (!kp || !(kp->flags & KPROBE_FLAG_ON_FUNC_ENTRY))
1078 		return 0;
1079 
1080 	return get_entry_ip((uintptr_t)kp->addr);
1081 }
1082 
1083 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
1084 	.func		= bpf_get_func_ip_kprobe,
1085 	.gpl_only	= true,
1086 	.ret_type	= RET_INTEGER,
1087 	.arg1_type	= ARG_PTR_TO_CTX,
1088 };
1089 
1090 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
1091 {
1092 	return bpf_kprobe_multi_entry_ip(current->bpf_ctx);
1093 }
1094 
1095 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
1096 	.func		= bpf_get_func_ip_kprobe_multi,
1097 	.gpl_only	= false,
1098 	.ret_type	= RET_INTEGER,
1099 	.arg1_type	= ARG_PTR_TO_CTX,
1100 };
1101 
1102 BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs)
1103 {
1104 	return bpf_kprobe_multi_cookie(current->bpf_ctx);
1105 }
1106 
1107 static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
1108 	.func		= bpf_get_attach_cookie_kprobe_multi,
1109 	.gpl_only	= false,
1110 	.ret_type	= RET_INTEGER,
1111 	.arg1_type	= ARG_PTR_TO_CTX,
1112 };
1113 
1114 BPF_CALL_1(bpf_get_func_ip_uprobe_multi, struct pt_regs *, regs)
1115 {
1116 	return bpf_uprobe_multi_entry_ip(current->bpf_ctx);
1117 }
1118 
1119 static const struct bpf_func_proto bpf_get_func_ip_proto_uprobe_multi = {
1120 	.func		= bpf_get_func_ip_uprobe_multi,
1121 	.gpl_only	= false,
1122 	.ret_type	= RET_INTEGER,
1123 	.arg1_type	= ARG_PTR_TO_CTX,
1124 };
1125 
1126 BPF_CALL_1(bpf_get_attach_cookie_uprobe_multi, struct pt_regs *, regs)
1127 {
1128 	return bpf_uprobe_multi_cookie(current->bpf_ctx);
1129 }
1130 
1131 static const struct bpf_func_proto bpf_get_attach_cookie_proto_umulti = {
1132 	.func		= bpf_get_attach_cookie_uprobe_multi,
1133 	.gpl_only	= false,
1134 	.ret_type	= RET_INTEGER,
1135 	.arg1_type	= ARG_PTR_TO_CTX,
1136 };
1137 
1138 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
1139 {
1140 	struct bpf_trace_run_ctx *run_ctx;
1141 
1142 	run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1143 	return run_ctx->bpf_cookie;
1144 }
1145 
1146 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
1147 	.func		= bpf_get_attach_cookie_trace,
1148 	.gpl_only	= false,
1149 	.ret_type	= RET_INTEGER,
1150 	.arg1_type	= ARG_PTR_TO_CTX,
1151 };
1152 
1153 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
1154 {
1155 	return ctx->event->bpf_cookie;
1156 }
1157 
1158 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
1159 	.func		= bpf_get_attach_cookie_pe,
1160 	.gpl_only	= false,
1161 	.ret_type	= RET_INTEGER,
1162 	.arg1_type	= ARG_PTR_TO_CTX,
1163 };
1164 
1165 BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx)
1166 {
1167 	struct bpf_trace_run_ctx *run_ctx;
1168 
1169 	run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1170 	return run_ctx->bpf_cookie;
1171 }
1172 
1173 static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = {
1174 	.func		= bpf_get_attach_cookie_tracing,
1175 	.gpl_only	= false,
1176 	.ret_type	= RET_INTEGER,
1177 	.arg1_type	= ARG_PTR_TO_CTX,
1178 };
1179 
1180 BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
1181 {
1182 #ifndef CONFIG_X86
1183 	return -ENOENT;
1184 #else
1185 	static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1186 	u32 entry_cnt = size / br_entry_size;
1187 
1188 	entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
1189 
1190 	if (unlikely(flags))
1191 		return -EINVAL;
1192 
1193 	if (!entry_cnt)
1194 		return -ENOENT;
1195 
1196 	return entry_cnt * br_entry_size;
1197 #endif
1198 }
1199 
1200 static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
1201 	.func		= bpf_get_branch_snapshot,
1202 	.gpl_only	= true,
1203 	.ret_type	= RET_INTEGER,
1204 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
1205 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
1206 };
1207 
1208 BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
1209 {
1210 	/* This helper call is inlined by verifier. */
1211 	u64 nr_args = ((u64 *)ctx)[-1];
1212 
1213 	if ((u64) n >= nr_args)
1214 		return -EINVAL;
1215 	*value = ((u64 *)ctx)[n];
1216 	return 0;
1217 }
1218 
1219 static const struct bpf_func_proto bpf_get_func_arg_proto = {
1220 	.func		= get_func_arg,
1221 	.ret_type	= RET_INTEGER,
1222 	.arg1_type	= ARG_PTR_TO_CTX,
1223 	.arg2_type	= ARG_ANYTHING,
1224 	.arg3_type	= ARG_PTR_TO_LONG,
1225 };
1226 
1227 BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
1228 {
1229 	/* This helper call is inlined by verifier. */
1230 	u64 nr_args = ((u64 *)ctx)[-1];
1231 
1232 	*value = ((u64 *)ctx)[nr_args];
1233 	return 0;
1234 }
1235 
1236 static const struct bpf_func_proto bpf_get_func_ret_proto = {
1237 	.func		= get_func_ret,
1238 	.ret_type	= RET_INTEGER,
1239 	.arg1_type	= ARG_PTR_TO_CTX,
1240 	.arg2_type	= ARG_PTR_TO_LONG,
1241 };
1242 
1243 BPF_CALL_1(get_func_arg_cnt, void *, ctx)
1244 {
1245 	/* This helper call is inlined by verifier. */
1246 	return ((u64 *)ctx)[-1];
1247 }
1248 
1249 static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
1250 	.func		= get_func_arg_cnt,
1251 	.ret_type	= RET_INTEGER,
1252 	.arg1_type	= ARG_PTR_TO_CTX,
1253 };
1254 
1255 #ifdef CONFIG_KEYS
1256 __bpf_kfunc_start_defs();
1257 
1258 /**
1259  * bpf_lookup_user_key - lookup a key by its serial
1260  * @serial: key handle serial number
1261  * @flags: lookup-specific flags
1262  *
1263  * Search a key with a given *serial* and the provided *flags*.
1264  * If found, increment the reference count of the key by one, and
1265  * return it in the bpf_key structure.
1266  *
1267  * The bpf_key structure must be passed to bpf_key_put() when done
1268  * with it, so that the key reference count is decremented and the
1269  * bpf_key structure is freed.
1270  *
1271  * Permission checks are deferred to the time the key is used by
1272  * one of the available key-specific kfuncs.
1273  *
1274  * Set *flags* with KEY_LOOKUP_CREATE, to attempt creating a requested
1275  * special keyring (e.g. session keyring), if it doesn't yet exist.
1276  * Set *flags* with KEY_LOOKUP_PARTIAL, to lookup a key without waiting
1277  * for the key construction, and to retrieve uninstantiated keys (keys
1278  * without data attached to them).
1279  *
1280  * Return: a bpf_key pointer with a valid key pointer if the key is found, a
1281  *         NULL pointer otherwise.
1282  */
1283 __bpf_kfunc struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags)
1284 {
1285 	key_ref_t key_ref;
1286 	struct bpf_key *bkey;
1287 
1288 	if (flags & ~KEY_LOOKUP_ALL)
1289 		return NULL;
1290 
1291 	/*
1292 	 * Permission check is deferred until the key is used, as the
1293 	 * intent of the caller is unknown here.
1294 	 */
1295 	key_ref = lookup_user_key(serial, flags, KEY_DEFER_PERM_CHECK);
1296 	if (IS_ERR(key_ref))
1297 		return NULL;
1298 
1299 	bkey = kmalloc(sizeof(*bkey), GFP_KERNEL);
1300 	if (!bkey) {
1301 		key_put(key_ref_to_ptr(key_ref));
1302 		return NULL;
1303 	}
1304 
1305 	bkey->key = key_ref_to_ptr(key_ref);
1306 	bkey->has_ref = true;
1307 
1308 	return bkey;
1309 }
1310 
1311 /**
1312  * bpf_lookup_system_key - lookup a key by a system-defined ID
1313  * @id: key ID
1314  *
1315  * Obtain a bpf_key structure with a key pointer set to the passed key ID.
1316  * The key pointer is marked as invalid, to prevent bpf_key_put() from
1317  * attempting to decrement the key reference count on that pointer. The key
1318  * pointer set in such way is currently understood only by
1319  * verify_pkcs7_signature().
1320  *
1321  * Set *id* to one of the values defined in include/linux/verification.h:
1322  * 0 for the primary keyring (immutable keyring of system keys);
1323  * VERIFY_USE_SECONDARY_KEYRING for both the primary and secondary keyring
1324  * (where keys can be added only if they are vouched for by existing keys
1325  * in those keyrings); VERIFY_USE_PLATFORM_KEYRING for the platform
1326  * keyring (primarily used by the integrity subsystem to verify a kexec'ed
1327  * kerned image and, possibly, the initramfs signature).
1328  *
1329  * Return: a bpf_key pointer with an invalid key pointer set from the
1330  *         pre-determined ID on success, a NULL pointer otherwise
1331  */
1332 __bpf_kfunc struct bpf_key *bpf_lookup_system_key(u64 id)
1333 {
1334 	struct bpf_key *bkey;
1335 
1336 	if (system_keyring_id_check(id) < 0)
1337 		return NULL;
1338 
1339 	bkey = kmalloc(sizeof(*bkey), GFP_ATOMIC);
1340 	if (!bkey)
1341 		return NULL;
1342 
1343 	bkey->key = (struct key *)(unsigned long)id;
1344 	bkey->has_ref = false;
1345 
1346 	return bkey;
1347 }
1348 
1349 /**
1350  * bpf_key_put - decrement key reference count if key is valid and free bpf_key
1351  * @bkey: bpf_key structure
1352  *
1353  * Decrement the reference count of the key inside *bkey*, if the pointer
1354  * is valid, and free *bkey*.
1355  */
1356 __bpf_kfunc void bpf_key_put(struct bpf_key *bkey)
1357 {
1358 	if (bkey->has_ref)
1359 		key_put(bkey->key);
1360 
1361 	kfree(bkey);
1362 }
1363 
1364 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1365 /**
1366  * bpf_verify_pkcs7_signature - verify a PKCS#7 signature
1367  * @data_ptr: data to verify
1368  * @sig_ptr: signature of the data
1369  * @trusted_keyring: keyring with keys trusted for signature verification
1370  *
1371  * Verify the PKCS#7 signature *sig_ptr* against the supplied *data_ptr*
1372  * with keys in a keyring referenced by *trusted_keyring*.
1373  *
1374  * Return: 0 on success, a negative value on error.
1375  */
1376 __bpf_kfunc int bpf_verify_pkcs7_signature(struct bpf_dynptr_kern *data_ptr,
1377 			       struct bpf_dynptr_kern *sig_ptr,
1378 			       struct bpf_key *trusted_keyring)
1379 {
1380 	const void *data, *sig;
1381 	u32 data_len, sig_len;
1382 	int ret;
1383 
1384 	if (trusted_keyring->has_ref) {
1385 		/*
1386 		 * Do the permission check deferred in bpf_lookup_user_key().
1387 		 * See bpf_lookup_user_key() for more details.
1388 		 *
1389 		 * A call to key_task_permission() here would be redundant, as
1390 		 * it is already done by keyring_search() called by
1391 		 * find_asymmetric_key().
1392 		 */
1393 		ret = key_validate(trusted_keyring->key);
1394 		if (ret < 0)
1395 			return ret;
1396 	}
1397 
1398 	data_len = __bpf_dynptr_size(data_ptr);
1399 	data = __bpf_dynptr_data(data_ptr, data_len);
1400 	sig_len = __bpf_dynptr_size(sig_ptr);
1401 	sig = __bpf_dynptr_data(sig_ptr, sig_len);
1402 
1403 	return verify_pkcs7_signature(data, data_len, sig, sig_len,
1404 				      trusted_keyring->key,
1405 				      VERIFYING_UNSPECIFIED_SIGNATURE, NULL,
1406 				      NULL);
1407 }
1408 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
1409 
1410 __bpf_kfunc_end_defs();
1411 
1412 BTF_SET8_START(key_sig_kfunc_set)
1413 BTF_ID_FLAGS(func, bpf_lookup_user_key, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE)
1414 BTF_ID_FLAGS(func, bpf_lookup_system_key, KF_ACQUIRE | KF_RET_NULL)
1415 BTF_ID_FLAGS(func, bpf_key_put, KF_RELEASE)
1416 #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
1417 BTF_ID_FLAGS(func, bpf_verify_pkcs7_signature, KF_SLEEPABLE)
1418 #endif
1419 BTF_SET8_END(key_sig_kfunc_set)
1420 
1421 static const struct btf_kfunc_id_set bpf_key_sig_kfunc_set = {
1422 	.owner = THIS_MODULE,
1423 	.set = &key_sig_kfunc_set,
1424 };
1425 
1426 static int __init bpf_key_sig_kfuncs_init(void)
1427 {
1428 	return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING,
1429 					 &bpf_key_sig_kfunc_set);
1430 }
1431 
1432 late_initcall(bpf_key_sig_kfuncs_init);
1433 #endif /* CONFIG_KEYS */
1434 
1435 /* filesystem kfuncs */
1436 __bpf_kfunc_start_defs();
1437 
1438 /**
1439  * bpf_get_file_xattr - get xattr of a file
1440  * @file: file to get xattr from
1441  * @name__str: name of the xattr
1442  * @value_ptr: output buffer of the xattr value
1443  *
1444  * Get xattr *name__str* of *file* and store the output in *value_ptr*.
1445  *
1446  * For security reasons, only *name__str* with prefix "user." is allowed.
1447  *
1448  * Return: 0 on success, a negative value on error.
1449  */
1450 __bpf_kfunc int bpf_get_file_xattr(struct file *file, const char *name__str,
1451 				   struct bpf_dynptr_kern *value_ptr)
1452 {
1453 	struct dentry *dentry;
1454 	u32 value_len;
1455 	void *value;
1456 	int ret;
1457 
1458 	if (strncmp(name__str, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
1459 		return -EPERM;
1460 
1461 	value_len = __bpf_dynptr_size(value_ptr);
1462 	value = __bpf_dynptr_data_rw(value_ptr, value_len);
1463 	if (!value)
1464 		return -EINVAL;
1465 
1466 	dentry = file_dentry(file);
1467 	ret = inode_permission(&nop_mnt_idmap, dentry->d_inode, MAY_READ);
1468 	if (ret)
1469 		return ret;
1470 	return __vfs_getxattr(dentry, dentry->d_inode, name__str, value, value_len);
1471 }
1472 
1473 __bpf_kfunc_end_defs();
1474 
1475 BTF_SET8_START(fs_kfunc_set_ids)
1476 BTF_ID_FLAGS(func, bpf_get_file_xattr, KF_SLEEPABLE | KF_TRUSTED_ARGS)
1477 BTF_SET8_END(fs_kfunc_set_ids)
1478 
1479 static int bpf_get_file_xattr_filter(const struct bpf_prog *prog, u32 kfunc_id)
1480 {
1481 	if (!btf_id_set8_contains(&fs_kfunc_set_ids, kfunc_id))
1482 		return 0;
1483 
1484 	/* Only allow to attach from LSM hooks, to avoid recursion */
1485 	return prog->type != BPF_PROG_TYPE_LSM ? -EACCES : 0;
1486 }
1487 
1488 static const struct btf_kfunc_id_set bpf_fs_kfunc_set = {
1489 	.owner = THIS_MODULE,
1490 	.set = &fs_kfunc_set_ids,
1491 	.filter = bpf_get_file_xattr_filter,
1492 };
1493 
1494 static int __init bpf_fs_kfuncs_init(void)
1495 {
1496 	return register_btf_kfunc_id_set(BPF_PROG_TYPE_LSM, &bpf_fs_kfunc_set);
1497 }
1498 
1499 late_initcall(bpf_fs_kfuncs_init);
1500 
1501 static const struct bpf_func_proto *
1502 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1503 {
1504 	switch (func_id) {
1505 	case BPF_FUNC_map_lookup_elem:
1506 		return &bpf_map_lookup_elem_proto;
1507 	case BPF_FUNC_map_update_elem:
1508 		return &bpf_map_update_elem_proto;
1509 	case BPF_FUNC_map_delete_elem:
1510 		return &bpf_map_delete_elem_proto;
1511 	case BPF_FUNC_map_push_elem:
1512 		return &bpf_map_push_elem_proto;
1513 	case BPF_FUNC_map_pop_elem:
1514 		return &bpf_map_pop_elem_proto;
1515 	case BPF_FUNC_map_peek_elem:
1516 		return &bpf_map_peek_elem_proto;
1517 	case BPF_FUNC_map_lookup_percpu_elem:
1518 		return &bpf_map_lookup_percpu_elem_proto;
1519 	case BPF_FUNC_ktime_get_ns:
1520 		return &bpf_ktime_get_ns_proto;
1521 	case BPF_FUNC_ktime_get_boot_ns:
1522 		return &bpf_ktime_get_boot_ns_proto;
1523 	case BPF_FUNC_tail_call:
1524 		return &bpf_tail_call_proto;
1525 	case BPF_FUNC_get_current_pid_tgid:
1526 		return &bpf_get_current_pid_tgid_proto;
1527 	case BPF_FUNC_get_current_task:
1528 		return &bpf_get_current_task_proto;
1529 	case BPF_FUNC_get_current_task_btf:
1530 		return &bpf_get_current_task_btf_proto;
1531 	case BPF_FUNC_task_pt_regs:
1532 		return &bpf_task_pt_regs_proto;
1533 	case BPF_FUNC_get_current_uid_gid:
1534 		return &bpf_get_current_uid_gid_proto;
1535 	case BPF_FUNC_get_current_comm:
1536 		return &bpf_get_current_comm_proto;
1537 	case BPF_FUNC_trace_printk:
1538 		return bpf_get_trace_printk_proto();
1539 	case BPF_FUNC_get_smp_processor_id:
1540 		return &bpf_get_smp_processor_id_proto;
1541 	case BPF_FUNC_get_numa_node_id:
1542 		return &bpf_get_numa_node_id_proto;
1543 	case BPF_FUNC_perf_event_read:
1544 		return &bpf_perf_event_read_proto;
1545 	case BPF_FUNC_current_task_under_cgroup:
1546 		return &bpf_current_task_under_cgroup_proto;
1547 	case BPF_FUNC_get_prandom_u32:
1548 		return &bpf_get_prandom_u32_proto;
1549 	case BPF_FUNC_probe_write_user:
1550 		return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
1551 		       NULL : bpf_get_probe_write_proto();
1552 	case BPF_FUNC_probe_read_user:
1553 		return &bpf_probe_read_user_proto;
1554 	case BPF_FUNC_probe_read_kernel:
1555 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1556 		       NULL : &bpf_probe_read_kernel_proto;
1557 	case BPF_FUNC_probe_read_user_str:
1558 		return &bpf_probe_read_user_str_proto;
1559 	case BPF_FUNC_probe_read_kernel_str:
1560 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1561 		       NULL : &bpf_probe_read_kernel_str_proto;
1562 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1563 	case BPF_FUNC_probe_read:
1564 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1565 		       NULL : &bpf_probe_read_compat_proto;
1566 	case BPF_FUNC_probe_read_str:
1567 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1568 		       NULL : &bpf_probe_read_compat_str_proto;
1569 #endif
1570 #ifdef CONFIG_CGROUPS
1571 	case BPF_FUNC_cgrp_storage_get:
1572 		return &bpf_cgrp_storage_get_proto;
1573 	case BPF_FUNC_cgrp_storage_delete:
1574 		return &bpf_cgrp_storage_delete_proto;
1575 #endif
1576 	case BPF_FUNC_send_signal:
1577 		return &bpf_send_signal_proto;
1578 	case BPF_FUNC_send_signal_thread:
1579 		return &bpf_send_signal_thread_proto;
1580 	case BPF_FUNC_perf_event_read_value:
1581 		return &bpf_perf_event_read_value_proto;
1582 	case BPF_FUNC_get_ns_current_pid_tgid:
1583 		return &bpf_get_ns_current_pid_tgid_proto;
1584 	case BPF_FUNC_ringbuf_output:
1585 		return &bpf_ringbuf_output_proto;
1586 	case BPF_FUNC_ringbuf_reserve:
1587 		return &bpf_ringbuf_reserve_proto;
1588 	case BPF_FUNC_ringbuf_submit:
1589 		return &bpf_ringbuf_submit_proto;
1590 	case BPF_FUNC_ringbuf_discard:
1591 		return &bpf_ringbuf_discard_proto;
1592 	case BPF_FUNC_ringbuf_query:
1593 		return &bpf_ringbuf_query_proto;
1594 	case BPF_FUNC_jiffies64:
1595 		return &bpf_jiffies64_proto;
1596 	case BPF_FUNC_get_task_stack:
1597 		return &bpf_get_task_stack_proto;
1598 	case BPF_FUNC_copy_from_user:
1599 		return &bpf_copy_from_user_proto;
1600 	case BPF_FUNC_copy_from_user_task:
1601 		return &bpf_copy_from_user_task_proto;
1602 	case BPF_FUNC_snprintf_btf:
1603 		return &bpf_snprintf_btf_proto;
1604 	case BPF_FUNC_per_cpu_ptr:
1605 		return &bpf_per_cpu_ptr_proto;
1606 	case BPF_FUNC_this_cpu_ptr:
1607 		return &bpf_this_cpu_ptr_proto;
1608 	case BPF_FUNC_task_storage_get:
1609 		if (bpf_prog_check_recur(prog))
1610 			return &bpf_task_storage_get_recur_proto;
1611 		return &bpf_task_storage_get_proto;
1612 	case BPF_FUNC_task_storage_delete:
1613 		if (bpf_prog_check_recur(prog))
1614 			return &bpf_task_storage_delete_recur_proto;
1615 		return &bpf_task_storage_delete_proto;
1616 	case BPF_FUNC_for_each_map_elem:
1617 		return &bpf_for_each_map_elem_proto;
1618 	case BPF_FUNC_snprintf:
1619 		return &bpf_snprintf_proto;
1620 	case BPF_FUNC_get_func_ip:
1621 		return &bpf_get_func_ip_proto_tracing;
1622 	case BPF_FUNC_get_branch_snapshot:
1623 		return &bpf_get_branch_snapshot_proto;
1624 	case BPF_FUNC_find_vma:
1625 		return &bpf_find_vma_proto;
1626 	case BPF_FUNC_trace_vprintk:
1627 		return bpf_get_trace_vprintk_proto();
1628 	default:
1629 		return bpf_base_func_proto(func_id);
1630 	}
1631 }
1632 
1633 static const struct bpf_func_proto *
1634 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1635 {
1636 	switch (func_id) {
1637 	case BPF_FUNC_perf_event_output:
1638 		return &bpf_perf_event_output_proto;
1639 	case BPF_FUNC_get_stackid:
1640 		return &bpf_get_stackid_proto;
1641 	case BPF_FUNC_get_stack:
1642 		return &bpf_get_stack_proto;
1643 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1644 	case BPF_FUNC_override_return:
1645 		return &bpf_override_return_proto;
1646 #endif
1647 	case BPF_FUNC_get_func_ip:
1648 		if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI)
1649 			return &bpf_get_func_ip_proto_kprobe_multi;
1650 		if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
1651 			return &bpf_get_func_ip_proto_uprobe_multi;
1652 		return &bpf_get_func_ip_proto_kprobe;
1653 	case BPF_FUNC_get_attach_cookie:
1654 		if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI)
1655 			return &bpf_get_attach_cookie_proto_kmulti;
1656 		if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI)
1657 			return &bpf_get_attach_cookie_proto_umulti;
1658 		return &bpf_get_attach_cookie_proto_trace;
1659 	default:
1660 		return bpf_tracing_func_proto(func_id, prog);
1661 	}
1662 }
1663 
1664 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
1665 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1666 					const struct bpf_prog *prog,
1667 					struct bpf_insn_access_aux *info)
1668 {
1669 	if (off < 0 || off >= sizeof(struct pt_regs))
1670 		return false;
1671 	if (type != BPF_READ)
1672 		return false;
1673 	if (off % size != 0)
1674 		return false;
1675 	/*
1676 	 * Assertion for 32 bit to make sure last 8 byte access
1677 	 * (BPF_DW) to the last 4 byte member is disallowed.
1678 	 */
1679 	if (off + size > sizeof(struct pt_regs))
1680 		return false;
1681 
1682 	return true;
1683 }
1684 
1685 const struct bpf_verifier_ops kprobe_verifier_ops = {
1686 	.get_func_proto  = kprobe_prog_func_proto,
1687 	.is_valid_access = kprobe_prog_is_valid_access,
1688 };
1689 
1690 const struct bpf_prog_ops kprobe_prog_ops = {
1691 };
1692 
1693 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1694 	   u64, flags, void *, data, u64, size)
1695 {
1696 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1697 
1698 	/*
1699 	 * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1700 	 * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1701 	 * from there and call the same bpf_perf_event_output() helper inline.
1702 	 */
1703 	return ____bpf_perf_event_output(regs, map, flags, data, size);
1704 }
1705 
1706 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1707 	.func		= bpf_perf_event_output_tp,
1708 	.gpl_only	= true,
1709 	.ret_type	= RET_INTEGER,
1710 	.arg1_type	= ARG_PTR_TO_CTX,
1711 	.arg2_type	= ARG_CONST_MAP_PTR,
1712 	.arg3_type	= ARG_ANYTHING,
1713 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1714 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
1715 };
1716 
1717 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1718 	   u64, flags)
1719 {
1720 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1721 
1722 	/*
1723 	 * Same comment as in bpf_perf_event_output_tp(), only that this time
1724 	 * the other helper's function body cannot be inlined due to being
1725 	 * external, thus we need to call raw helper function.
1726 	 */
1727 	return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1728 			       flags, 0, 0);
1729 }
1730 
1731 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1732 	.func		= bpf_get_stackid_tp,
1733 	.gpl_only	= true,
1734 	.ret_type	= RET_INTEGER,
1735 	.arg1_type	= ARG_PTR_TO_CTX,
1736 	.arg2_type	= ARG_CONST_MAP_PTR,
1737 	.arg3_type	= ARG_ANYTHING,
1738 };
1739 
1740 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1741 	   u64, flags)
1742 {
1743 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1744 
1745 	return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1746 			     (unsigned long) size, flags, 0);
1747 }
1748 
1749 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1750 	.func		= bpf_get_stack_tp,
1751 	.gpl_only	= true,
1752 	.ret_type	= RET_INTEGER,
1753 	.arg1_type	= ARG_PTR_TO_CTX,
1754 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
1755 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
1756 	.arg4_type	= ARG_ANYTHING,
1757 };
1758 
1759 static const struct bpf_func_proto *
1760 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1761 {
1762 	switch (func_id) {
1763 	case BPF_FUNC_perf_event_output:
1764 		return &bpf_perf_event_output_proto_tp;
1765 	case BPF_FUNC_get_stackid:
1766 		return &bpf_get_stackid_proto_tp;
1767 	case BPF_FUNC_get_stack:
1768 		return &bpf_get_stack_proto_tp;
1769 	case BPF_FUNC_get_attach_cookie:
1770 		return &bpf_get_attach_cookie_proto_trace;
1771 	default:
1772 		return bpf_tracing_func_proto(func_id, prog);
1773 	}
1774 }
1775 
1776 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1777 				    const struct bpf_prog *prog,
1778 				    struct bpf_insn_access_aux *info)
1779 {
1780 	if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1781 		return false;
1782 	if (type != BPF_READ)
1783 		return false;
1784 	if (off % size != 0)
1785 		return false;
1786 
1787 	BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1788 	return true;
1789 }
1790 
1791 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1792 	.get_func_proto  = tp_prog_func_proto,
1793 	.is_valid_access = tp_prog_is_valid_access,
1794 };
1795 
1796 const struct bpf_prog_ops tracepoint_prog_ops = {
1797 };
1798 
1799 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1800 	   struct bpf_perf_event_value *, buf, u32, size)
1801 {
1802 	int err = -EINVAL;
1803 
1804 	if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1805 		goto clear;
1806 	err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1807 				    &buf->running);
1808 	if (unlikely(err))
1809 		goto clear;
1810 	return 0;
1811 clear:
1812 	memset(buf, 0, size);
1813 	return err;
1814 }
1815 
1816 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1817          .func           = bpf_perf_prog_read_value,
1818          .gpl_only       = true,
1819          .ret_type       = RET_INTEGER,
1820          .arg1_type      = ARG_PTR_TO_CTX,
1821          .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
1822          .arg3_type      = ARG_CONST_SIZE,
1823 };
1824 
1825 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1826 	   void *, buf, u32, size, u64, flags)
1827 {
1828 	static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1829 	struct perf_branch_stack *br_stack = ctx->data->br_stack;
1830 	u32 to_copy;
1831 
1832 	if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1833 		return -EINVAL;
1834 
1835 	if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
1836 		return -ENOENT;
1837 
1838 	if (unlikely(!br_stack))
1839 		return -ENOENT;
1840 
1841 	if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1842 		return br_stack->nr * br_entry_size;
1843 
1844 	if (!buf || (size % br_entry_size != 0))
1845 		return -EINVAL;
1846 
1847 	to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1848 	memcpy(buf, br_stack->entries, to_copy);
1849 
1850 	return to_copy;
1851 }
1852 
1853 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1854 	.func           = bpf_read_branch_records,
1855 	.gpl_only       = true,
1856 	.ret_type       = RET_INTEGER,
1857 	.arg1_type      = ARG_PTR_TO_CTX,
1858 	.arg2_type      = ARG_PTR_TO_MEM_OR_NULL,
1859 	.arg3_type      = ARG_CONST_SIZE_OR_ZERO,
1860 	.arg4_type      = ARG_ANYTHING,
1861 };
1862 
1863 static const struct bpf_func_proto *
1864 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1865 {
1866 	switch (func_id) {
1867 	case BPF_FUNC_perf_event_output:
1868 		return &bpf_perf_event_output_proto_tp;
1869 	case BPF_FUNC_get_stackid:
1870 		return &bpf_get_stackid_proto_pe;
1871 	case BPF_FUNC_get_stack:
1872 		return &bpf_get_stack_proto_pe;
1873 	case BPF_FUNC_perf_prog_read_value:
1874 		return &bpf_perf_prog_read_value_proto;
1875 	case BPF_FUNC_read_branch_records:
1876 		return &bpf_read_branch_records_proto;
1877 	case BPF_FUNC_get_attach_cookie:
1878 		return &bpf_get_attach_cookie_proto_pe;
1879 	default:
1880 		return bpf_tracing_func_proto(func_id, prog);
1881 	}
1882 }
1883 
1884 /*
1885  * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1886  * to avoid potential recursive reuse issue when/if tracepoints are added
1887  * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1888  *
1889  * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1890  * in normal, irq, and nmi context.
1891  */
1892 struct bpf_raw_tp_regs {
1893 	struct pt_regs regs[3];
1894 };
1895 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1896 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
1897 static struct pt_regs *get_bpf_raw_tp_regs(void)
1898 {
1899 	struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1900 	int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1901 
1902 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1903 		this_cpu_dec(bpf_raw_tp_nest_level);
1904 		return ERR_PTR(-EBUSY);
1905 	}
1906 
1907 	return &tp_regs->regs[nest_level - 1];
1908 }
1909 
1910 static void put_bpf_raw_tp_regs(void)
1911 {
1912 	this_cpu_dec(bpf_raw_tp_nest_level);
1913 }
1914 
1915 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1916 	   struct bpf_map *, map, u64, flags, void *, data, u64, size)
1917 {
1918 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1919 	int ret;
1920 
1921 	if (IS_ERR(regs))
1922 		return PTR_ERR(regs);
1923 
1924 	perf_fetch_caller_regs(regs);
1925 	ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1926 
1927 	put_bpf_raw_tp_regs();
1928 	return ret;
1929 }
1930 
1931 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1932 	.func		= bpf_perf_event_output_raw_tp,
1933 	.gpl_only	= true,
1934 	.ret_type	= RET_INTEGER,
1935 	.arg1_type	= ARG_PTR_TO_CTX,
1936 	.arg2_type	= ARG_CONST_MAP_PTR,
1937 	.arg3_type	= ARG_ANYTHING,
1938 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1939 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
1940 };
1941 
1942 extern const struct bpf_func_proto bpf_skb_output_proto;
1943 extern const struct bpf_func_proto bpf_xdp_output_proto;
1944 extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
1945 
1946 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1947 	   struct bpf_map *, map, u64, flags)
1948 {
1949 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1950 	int ret;
1951 
1952 	if (IS_ERR(regs))
1953 		return PTR_ERR(regs);
1954 
1955 	perf_fetch_caller_regs(regs);
1956 	/* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1957 	ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1958 			      flags, 0, 0);
1959 	put_bpf_raw_tp_regs();
1960 	return ret;
1961 }
1962 
1963 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1964 	.func		= bpf_get_stackid_raw_tp,
1965 	.gpl_only	= true,
1966 	.ret_type	= RET_INTEGER,
1967 	.arg1_type	= ARG_PTR_TO_CTX,
1968 	.arg2_type	= ARG_CONST_MAP_PTR,
1969 	.arg3_type	= ARG_ANYTHING,
1970 };
1971 
1972 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1973 	   void *, buf, u32, size, u64, flags)
1974 {
1975 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1976 	int ret;
1977 
1978 	if (IS_ERR(regs))
1979 		return PTR_ERR(regs);
1980 
1981 	perf_fetch_caller_regs(regs);
1982 	ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1983 			    (unsigned long) size, flags, 0);
1984 	put_bpf_raw_tp_regs();
1985 	return ret;
1986 }
1987 
1988 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1989 	.func		= bpf_get_stack_raw_tp,
1990 	.gpl_only	= true,
1991 	.ret_type	= RET_INTEGER,
1992 	.arg1_type	= ARG_PTR_TO_CTX,
1993 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1994 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
1995 	.arg4_type	= ARG_ANYTHING,
1996 };
1997 
1998 static const struct bpf_func_proto *
1999 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
2000 {
2001 	switch (func_id) {
2002 	case BPF_FUNC_perf_event_output:
2003 		return &bpf_perf_event_output_proto_raw_tp;
2004 	case BPF_FUNC_get_stackid:
2005 		return &bpf_get_stackid_proto_raw_tp;
2006 	case BPF_FUNC_get_stack:
2007 		return &bpf_get_stack_proto_raw_tp;
2008 	default:
2009 		return bpf_tracing_func_proto(func_id, prog);
2010 	}
2011 }
2012 
2013 const struct bpf_func_proto *
2014 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
2015 {
2016 	const struct bpf_func_proto *fn;
2017 
2018 	switch (func_id) {
2019 #ifdef CONFIG_NET
2020 	case BPF_FUNC_skb_output:
2021 		return &bpf_skb_output_proto;
2022 	case BPF_FUNC_xdp_output:
2023 		return &bpf_xdp_output_proto;
2024 	case BPF_FUNC_skc_to_tcp6_sock:
2025 		return &bpf_skc_to_tcp6_sock_proto;
2026 	case BPF_FUNC_skc_to_tcp_sock:
2027 		return &bpf_skc_to_tcp_sock_proto;
2028 	case BPF_FUNC_skc_to_tcp_timewait_sock:
2029 		return &bpf_skc_to_tcp_timewait_sock_proto;
2030 	case BPF_FUNC_skc_to_tcp_request_sock:
2031 		return &bpf_skc_to_tcp_request_sock_proto;
2032 	case BPF_FUNC_skc_to_udp6_sock:
2033 		return &bpf_skc_to_udp6_sock_proto;
2034 	case BPF_FUNC_skc_to_unix_sock:
2035 		return &bpf_skc_to_unix_sock_proto;
2036 	case BPF_FUNC_skc_to_mptcp_sock:
2037 		return &bpf_skc_to_mptcp_sock_proto;
2038 	case BPF_FUNC_sk_storage_get:
2039 		return &bpf_sk_storage_get_tracing_proto;
2040 	case BPF_FUNC_sk_storage_delete:
2041 		return &bpf_sk_storage_delete_tracing_proto;
2042 	case BPF_FUNC_sock_from_file:
2043 		return &bpf_sock_from_file_proto;
2044 	case BPF_FUNC_get_socket_cookie:
2045 		return &bpf_get_socket_ptr_cookie_proto;
2046 	case BPF_FUNC_xdp_get_buff_len:
2047 		return &bpf_xdp_get_buff_len_trace_proto;
2048 #endif
2049 	case BPF_FUNC_seq_printf:
2050 		return prog->expected_attach_type == BPF_TRACE_ITER ?
2051 		       &bpf_seq_printf_proto :
2052 		       NULL;
2053 	case BPF_FUNC_seq_write:
2054 		return prog->expected_attach_type == BPF_TRACE_ITER ?
2055 		       &bpf_seq_write_proto :
2056 		       NULL;
2057 	case BPF_FUNC_seq_printf_btf:
2058 		return prog->expected_attach_type == BPF_TRACE_ITER ?
2059 		       &bpf_seq_printf_btf_proto :
2060 		       NULL;
2061 	case BPF_FUNC_d_path:
2062 		return &bpf_d_path_proto;
2063 	case BPF_FUNC_get_func_arg:
2064 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
2065 	case BPF_FUNC_get_func_ret:
2066 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
2067 	case BPF_FUNC_get_func_arg_cnt:
2068 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
2069 	case BPF_FUNC_get_attach_cookie:
2070 		return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL;
2071 	default:
2072 		fn = raw_tp_prog_func_proto(func_id, prog);
2073 		if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
2074 			fn = bpf_iter_get_func_proto(func_id, prog);
2075 		return fn;
2076 	}
2077 }
2078 
2079 static bool raw_tp_prog_is_valid_access(int off, int size,
2080 					enum bpf_access_type type,
2081 					const struct bpf_prog *prog,
2082 					struct bpf_insn_access_aux *info)
2083 {
2084 	return bpf_tracing_ctx_access(off, size, type);
2085 }
2086 
2087 static bool tracing_prog_is_valid_access(int off, int size,
2088 					 enum bpf_access_type type,
2089 					 const struct bpf_prog *prog,
2090 					 struct bpf_insn_access_aux *info)
2091 {
2092 	return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
2093 }
2094 
2095 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
2096 				     const union bpf_attr *kattr,
2097 				     union bpf_attr __user *uattr)
2098 {
2099 	return -ENOTSUPP;
2100 }
2101 
2102 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
2103 	.get_func_proto  = raw_tp_prog_func_proto,
2104 	.is_valid_access = raw_tp_prog_is_valid_access,
2105 };
2106 
2107 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
2108 #ifdef CONFIG_NET
2109 	.test_run = bpf_prog_test_run_raw_tp,
2110 #endif
2111 };
2112 
2113 const struct bpf_verifier_ops tracing_verifier_ops = {
2114 	.get_func_proto  = tracing_prog_func_proto,
2115 	.is_valid_access = tracing_prog_is_valid_access,
2116 };
2117 
2118 const struct bpf_prog_ops tracing_prog_ops = {
2119 	.test_run = bpf_prog_test_run_tracing,
2120 };
2121 
2122 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
2123 						 enum bpf_access_type type,
2124 						 const struct bpf_prog *prog,
2125 						 struct bpf_insn_access_aux *info)
2126 {
2127 	if (off == 0) {
2128 		if (size != sizeof(u64) || type != BPF_READ)
2129 			return false;
2130 		info->reg_type = PTR_TO_TP_BUFFER;
2131 	}
2132 	return raw_tp_prog_is_valid_access(off, size, type, prog, info);
2133 }
2134 
2135 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
2136 	.get_func_proto  = raw_tp_prog_func_proto,
2137 	.is_valid_access = raw_tp_writable_prog_is_valid_access,
2138 };
2139 
2140 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
2141 };
2142 
2143 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
2144 				    const struct bpf_prog *prog,
2145 				    struct bpf_insn_access_aux *info)
2146 {
2147 	const int size_u64 = sizeof(u64);
2148 
2149 	if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
2150 		return false;
2151 	if (type != BPF_READ)
2152 		return false;
2153 	if (off % size != 0) {
2154 		if (sizeof(unsigned long) != 4)
2155 			return false;
2156 		if (size != 8)
2157 			return false;
2158 		if (off % size != 4)
2159 			return false;
2160 	}
2161 
2162 	switch (off) {
2163 	case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
2164 		bpf_ctx_record_field_size(info, size_u64);
2165 		if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2166 			return false;
2167 		break;
2168 	case bpf_ctx_range(struct bpf_perf_event_data, addr):
2169 		bpf_ctx_record_field_size(info, size_u64);
2170 		if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
2171 			return false;
2172 		break;
2173 	default:
2174 		if (size != sizeof(long))
2175 			return false;
2176 	}
2177 
2178 	return true;
2179 }
2180 
2181 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
2182 				      const struct bpf_insn *si,
2183 				      struct bpf_insn *insn_buf,
2184 				      struct bpf_prog *prog, u32 *target_size)
2185 {
2186 	struct bpf_insn *insn = insn_buf;
2187 
2188 	switch (si->off) {
2189 	case offsetof(struct bpf_perf_event_data, sample_period):
2190 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2191 						       data), si->dst_reg, si->src_reg,
2192 				      offsetof(struct bpf_perf_event_data_kern, data));
2193 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2194 				      bpf_target_off(struct perf_sample_data, period, 8,
2195 						     target_size));
2196 		break;
2197 	case offsetof(struct bpf_perf_event_data, addr):
2198 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2199 						       data), si->dst_reg, si->src_reg,
2200 				      offsetof(struct bpf_perf_event_data_kern, data));
2201 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
2202 				      bpf_target_off(struct perf_sample_data, addr, 8,
2203 						     target_size));
2204 		break;
2205 	default:
2206 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
2207 						       regs), si->dst_reg, si->src_reg,
2208 				      offsetof(struct bpf_perf_event_data_kern, regs));
2209 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
2210 				      si->off);
2211 		break;
2212 	}
2213 
2214 	return insn - insn_buf;
2215 }
2216 
2217 const struct bpf_verifier_ops perf_event_verifier_ops = {
2218 	.get_func_proto		= pe_prog_func_proto,
2219 	.is_valid_access	= pe_prog_is_valid_access,
2220 	.convert_ctx_access	= pe_prog_convert_ctx_access,
2221 };
2222 
2223 const struct bpf_prog_ops perf_event_prog_ops = {
2224 };
2225 
2226 static DEFINE_MUTEX(bpf_event_mutex);
2227 
2228 #define BPF_TRACE_MAX_PROGS 64
2229 
2230 int perf_event_attach_bpf_prog(struct perf_event *event,
2231 			       struct bpf_prog *prog,
2232 			       u64 bpf_cookie)
2233 {
2234 	struct bpf_prog_array *old_array;
2235 	struct bpf_prog_array *new_array;
2236 	int ret = -EEXIST;
2237 
2238 	/*
2239 	 * Kprobe override only works if they are on the function entry,
2240 	 * and only if they are on the opt-in list.
2241 	 */
2242 	if (prog->kprobe_override &&
2243 	    (!trace_kprobe_on_func_entry(event->tp_event) ||
2244 	     !trace_kprobe_error_injectable(event->tp_event)))
2245 		return -EINVAL;
2246 
2247 	mutex_lock(&bpf_event_mutex);
2248 
2249 	if (event->prog)
2250 		goto unlock;
2251 
2252 	old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2253 	if (old_array &&
2254 	    bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
2255 		ret = -E2BIG;
2256 		goto unlock;
2257 	}
2258 
2259 	ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
2260 	if (ret < 0)
2261 		goto unlock;
2262 
2263 	/* set the new array to event->tp_event and set event->prog */
2264 	event->prog = prog;
2265 	event->bpf_cookie = bpf_cookie;
2266 	rcu_assign_pointer(event->tp_event->prog_array, new_array);
2267 	bpf_prog_array_free_sleepable(old_array);
2268 
2269 unlock:
2270 	mutex_unlock(&bpf_event_mutex);
2271 	return ret;
2272 }
2273 
2274 void perf_event_detach_bpf_prog(struct perf_event *event)
2275 {
2276 	struct bpf_prog_array *old_array;
2277 	struct bpf_prog_array *new_array;
2278 	int ret;
2279 
2280 	mutex_lock(&bpf_event_mutex);
2281 
2282 	if (!event->prog)
2283 		goto unlock;
2284 
2285 	old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
2286 	ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
2287 	if (ret == -ENOENT)
2288 		goto unlock;
2289 	if (ret < 0) {
2290 		bpf_prog_array_delete_safe(old_array, event->prog);
2291 	} else {
2292 		rcu_assign_pointer(event->tp_event->prog_array, new_array);
2293 		bpf_prog_array_free_sleepable(old_array);
2294 	}
2295 
2296 	bpf_prog_put(event->prog);
2297 	event->prog = NULL;
2298 
2299 unlock:
2300 	mutex_unlock(&bpf_event_mutex);
2301 }
2302 
2303 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
2304 {
2305 	struct perf_event_query_bpf __user *uquery = info;
2306 	struct perf_event_query_bpf query = {};
2307 	struct bpf_prog_array *progs;
2308 	u32 *ids, prog_cnt, ids_len;
2309 	int ret;
2310 
2311 	if (!perfmon_capable())
2312 		return -EPERM;
2313 	if (event->attr.type != PERF_TYPE_TRACEPOINT)
2314 		return -EINVAL;
2315 	if (copy_from_user(&query, uquery, sizeof(query)))
2316 		return -EFAULT;
2317 
2318 	ids_len = query.ids_len;
2319 	if (ids_len > BPF_TRACE_MAX_PROGS)
2320 		return -E2BIG;
2321 	ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
2322 	if (!ids)
2323 		return -ENOMEM;
2324 	/*
2325 	 * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
2326 	 * is required when user only wants to check for uquery->prog_cnt.
2327 	 * There is no need to check for it since the case is handled
2328 	 * gracefully in bpf_prog_array_copy_info.
2329 	 */
2330 
2331 	mutex_lock(&bpf_event_mutex);
2332 	progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
2333 	ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
2334 	mutex_unlock(&bpf_event_mutex);
2335 
2336 	if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
2337 	    copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
2338 		ret = -EFAULT;
2339 
2340 	kfree(ids);
2341 	return ret;
2342 }
2343 
2344 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
2345 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
2346 
2347 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
2348 {
2349 	struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
2350 
2351 	for (; btp < __stop__bpf_raw_tp; btp++) {
2352 		if (!strcmp(btp->tp->name, name))
2353 			return btp;
2354 	}
2355 
2356 	return bpf_get_raw_tracepoint_module(name);
2357 }
2358 
2359 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
2360 {
2361 	struct module *mod;
2362 
2363 	preempt_disable();
2364 	mod = __module_address((unsigned long)btp);
2365 	module_put(mod);
2366 	preempt_enable();
2367 }
2368 
2369 static __always_inline
2370 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
2371 {
2372 	cant_sleep();
2373 	if (unlikely(this_cpu_inc_return(*(prog->active)) != 1)) {
2374 		bpf_prog_inc_misses_counter(prog);
2375 		goto out;
2376 	}
2377 	rcu_read_lock();
2378 	(void) bpf_prog_run(prog, args);
2379 	rcu_read_unlock();
2380 out:
2381 	this_cpu_dec(*(prog->active));
2382 }
2383 
2384 #define UNPACK(...)			__VA_ARGS__
2385 #define REPEAT_1(FN, DL, X, ...)	FN(X)
2386 #define REPEAT_2(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
2387 #define REPEAT_3(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
2388 #define REPEAT_4(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
2389 #define REPEAT_5(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
2390 #define REPEAT_6(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
2391 #define REPEAT_7(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
2392 #define REPEAT_8(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
2393 #define REPEAT_9(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
2394 #define REPEAT_10(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
2395 #define REPEAT_11(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
2396 #define REPEAT_12(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
2397 #define REPEAT(X, FN, DL, ...)		REPEAT_##X(FN, DL, __VA_ARGS__)
2398 
2399 #define SARG(X)		u64 arg##X
2400 #define COPY(X)		args[X] = arg##X
2401 
2402 #define __DL_COM	(,)
2403 #define __DL_SEM	(;)
2404 
2405 #define __SEQ_0_11	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
2406 
2407 #define BPF_TRACE_DEFN_x(x)						\
2408 	void bpf_trace_run##x(struct bpf_prog *prog,			\
2409 			      REPEAT(x, SARG, __DL_COM, __SEQ_0_11))	\
2410 	{								\
2411 		u64 args[x];						\
2412 		REPEAT(x, COPY, __DL_SEM, __SEQ_0_11);			\
2413 		__bpf_trace_run(prog, args);				\
2414 	}								\
2415 	EXPORT_SYMBOL_GPL(bpf_trace_run##x)
2416 BPF_TRACE_DEFN_x(1);
2417 BPF_TRACE_DEFN_x(2);
2418 BPF_TRACE_DEFN_x(3);
2419 BPF_TRACE_DEFN_x(4);
2420 BPF_TRACE_DEFN_x(5);
2421 BPF_TRACE_DEFN_x(6);
2422 BPF_TRACE_DEFN_x(7);
2423 BPF_TRACE_DEFN_x(8);
2424 BPF_TRACE_DEFN_x(9);
2425 BPF_TRACE_DEFN_x(10);
2426 BPF_TRACE_DEFN_x(11);
2427 BPF_TRACE_DEFN_x(12);
2428 
2429 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2430 {
2431 	struct tracepoint *tp = btp->tp;
2432 
2433 	/*
2434 	 * check that program doesn't access arguments beyond what's
2435 	 * available in this tracepoint
2436 	 */
2437 	if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
2438 		return -EINVAL;
2439 
2440 	if (prog->aux->max_tp_access > btp->writable_size)
2441 		return -EINVAL;
2442 
2443 	return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
2444 						   prog);
2445 }
2446 
2447 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2448 {
2449 	return __bpf_probe_register(btp, prog);
2450 }
2451 
2452 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2453 {
2454 	return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
2455 }
2456 
2457 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
2458 			    u32 *fd_type, const char **buf,
2459 			    u64 *probe_offset, u64 *probe_addr,
2460 			    unsigned long *missed)
2461 {
2462 	bool is_tracepoint, is_syscall_tp;
2463 	struct bpf_prog *prog;
2464 	int flags, err = 0;
2465 
2466 	prog = event->prog;
2467 	if (!prog)
2468 		return -ENOENT;
2469 
2470 	/* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
2471 	if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
2472 		return -EOPNOTSUPP;
2473 
2474 	*prog_id = prog->aux->id;
2475 	flags = event->tp_event->flags;
2476 	is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
2477 	is_syscall_tp = is_syscall_trace_event(event->tp_event);
2478 
2479 	if (is_tracepoint || is_syscall_tp) {
2480 		*buf = is_tracepoint ? event->tp_event->tp->name
2481 				     : event->tp_event->name;
2482 		/* We allow NULL pointer for tracepoint */
2483 		if (fd_type)
2484 			*fd_type = BPF_FD_TYPE_TRACEPOINT;
2485 		if (probe_offset)
2486 			*probe_offset = 0x0;
2487 		if (probe_addr)
2488 			*probe_addr = 0x0;
2489 	} else {
2490 		/* kprobe/uprobe */
2491 		err = -EOPNOTSUPP;
2492 #ifdef CONFIG_KPROBE_EVENTS
2493 		if (flags & TRACE_EVENT_FL_KPROBE)
2494 			err = bpf_get_kprobe_info(event, fd_type, buf,
2495 						  probe_offset, probe_addr, missed,
2496 						  event->attr.type == PERF_TYPE_TRACEPOINT);
2497 #endif
2498 #ifdef CONFIG_UPROBE_EVENTS
2499 		if (flags & TRACE_EVENT_FL_UPROBE)
2500 			err = bpf_get_uprobe_info(event, fd_type, buf,
2501 						  probe_offset, probe_addr,
2502 						  event->attr.type == PERF_TYPE_TRACEPOINT);
2503 #endif
2504 	}
2505 
2506 	return err;
2507 }
2508 
2509 static int __init send_signal_irq_work_init(void)
2510 {
2511 	int cpu;
2512 	struct send_signal_irq_work *work;
2513 
2514 	for_each_possible_cpu(cpu) {
2515 		work = per_cpu_ptr(&send_signal_work, cpu);
2516 		init_irq_work(&work->irq_work, do_bpf_send_signal);
2517 	}
2518 	return 0;
2519 }
2520 
2521 subsys_initcall(send_signal_irq_work_init);
2522 
2523 #ifdef CONFIG_MODULES
2524 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
2525 			    void *module)
2526 {
2527 	struct bpf_trace_module *btm, *tmp;
2528 	struct module *mod = module;
2529 	int ret = 0;
2530 
2531 	if (mod->num_bpf_raw_events == 0 ||
2532 	    (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
2533 		goto out;
2534 
2535 	mutex_lock(&bpf_module_mutex);
2536 
2537 	switch (op) {
2538 	case MODULE_STATE_COMING:
2539 		btm = kzalloc(sizeof(*btm), GFP_KERNEL);
2540 		if (btm) {
2541 			btm->module = module;
2542 			list_add(&btm->list, &bpf_trace_modules);
2543 		} else {
2544 			ret = -ENOMEM;
2545 		}
2546 		break;
2547 	case MODULE_STATE_GOING:
2548 		list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
2549 			if (btm->module == module) {
2550 				list_del(&btm->list);
2551 				kfree(btm);
2552 				break;
2553 			}
2554 		}
2555 		break;
2556 	}
2557 
2558 	mutex_unlock(&bpf_module_mutex);
2559 
2560 out:
2561 	return notifier_from_errno(ret);
2562 }
2563 
2564 static struct notifier_block bpf_module_nb = {
2565 	.notifier_call = bpf_event_notify,
2566 };
2567 
2568 static int __init bpf_event_init(void)
2569 {
2570 	register_module_notifier(&bpf_module_nb);
2571 	return 0;
2572 }
2573 
2574 fs_initcall(bpf_event_init);
2575 #endif /* CONFIG_MODULES */
2576 
2577 #ifdef CONFIG_FPROBE
2578 struct bpf_kprobe_multi_link {
2579 	struct bpf_link link;
2580 	struct fprobe fp;
2581 	unsigned long *addrs;
2582 	u64 *cookies;
2583 	u32 cnt;
2584 	u32 mods_cnt;
2585 	struct module **mods;
2586 	u32 flags;
2587 };
2588 
2589 struct bpf_kprobe_multi_run_ctx {
2590 	struct bpf_run_ctx run_ctx;
2591 	struct bpf_kprobe_multi_link *link;
2592 	unsigned long entry_ip;
2593 };
2594 
2595 struct user_syms {
2596 	const char **syms;
2597 	char *buf;
2598 };
2599 
2600 static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
2601 {
2602 	unsigned long __user usymbol;
2603 	const char **syms = NULL;
2604 	char *buf = NULL, *p;
2605 	int err = -ENOMEM;
2606 	unsigned int i;
2607 
2608 	syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
2609 	if (!syms)
2610 		goto error;
2611 
2612 	buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
2613 	if (!buf)
2614 		goto error;
2615 
2616 	for (p = buf, i = 0; i < cnt; i++) {
2617 		if (__get_user(usymbol, usyms + i)) {
2618 			err = -EFAULT;
2619 			goto error;
2620 		}
2621 		err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN);
2622 		if (err == KSYM_NAME_LEN)
2623 			err = -E2BIG;
2624 		if (err < 0)
2625 			goto error;
2626 		syms[i] = p;
2627 		p += err + 1;
2628 	}
2629 
2630 	us->syms = syms;
2631 	us->buf = buf;
2632 	return 0;
2633 
2634 error:
2635 	if (err) {
2636 		kvfree(syms);
2637 		kvfree(buf);
2638 	}
2639 	return err;
2640 }
2641 
2642 static void kprobe_multi_put_modules(struct module **mods, u32 cnt)
2643 {
2644 	u32 i;
2645 
2646 	for (i = 0; i < cnt; i++)
2647 		module_put(mods[i]);
2648 }
2649 
2650 static void free_user_syms(struct user_syms *us)
2651 {
2652 	kvfree(us->syms);
2653 	kvfree(us->buf);
2654 }
2655 
2656 static void bpf_kprobe_multi_link_release(struct bpf_link *link)
2657 {
2658 	struct bpf_kprobe_multi_link *kmulti_link;
2659 
2660 	kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2661 	unregister_fprobe(&kmulti_link->fp);
2662 	kprobe_multi_put_modules(kmulti_link->mods, kmulti_link->mods_cnt);
2663 }
2664 
2665 static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
2666 {
2667 	struct bpf_kprobe_multi_link *kmulti_link;
2668 
2669 	kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2670 	kvfree(kmulti_link->addrs);
2671 	kvfree(kmulti_link->cookies);
2672 	kfree(kmulti_link->mods);
2673 	kfree(kmulti_link);
2674 }
2675 
2676 static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link,
2677 						struct bpf_link_info *info)
2678 {
2679 	u64 __user *uaddrs = u64_to_user_ptr(info->kprobe_multi.addrs);
2680 	struct bpf_kprobe_multi_link *kmulti_link;
2681 	u32 ucount = info->kprobe_multi.count;
2682 	int err = 0, i;
2683 
2684 	if (!uaddrs ^ !ucount)
2685 		return -EINVAL;
2686 
2687 	kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2688 	info->kprobe_multi.count = kmulti_link->cnt;
2689 	info->kprobe_multi.flags = kmulti_link->flags;
2690 	info->kprobe_multi.missed = kmulti_link->fp.nmissed;
2691 
2692 	if (!uaddrs)
2693 		return 0;
2694 	if (ucount < kmulti_link->cnt)
2695 		err = -ENOSPC;
2696 	else
2697 		ucount = kmulti_link->cnt;
2698 
2699 	if (kallsyms_show_value(current_cred())) {
2700 		if (copy_to_user(uaddrs, kmulti_link->addrs, ucount * sizeof(u64)))
2701 			return -EFAULT;
2702 	} else {
2703 		for (i = 0; i < ucount; i++) {
2704 			if (put_user(0, uaddrs + i))
2705 				return -EFAULT;
2706 		}
2707 	}
2708 	return err;
2709 }
2710 
2711 static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
2712 	.release = bpf_kprobe_multi_link_release,
2713 	.dealloc = bpf_kprobe_multi_link_dealloc,
2714 	.fill_link_info = bpf_kprobe_multi_link_fill_link_info,
2715 };
2716 
2717 static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
2718 {
2719 	const struct bpf_kprobe_multi_link *link = priv;
2720 	unsigned long *addr_a = a, *addr_b = b;
2721 	u64 *cookie_a, *cookie_b;
2722 
2723 	cookie_a = link->cookies + (addr_a - link->addrs);
2724 	cookie_b = link->cookies + (addr_b - link->addrs);
2725 
2726 	/* swap addr_a/addr_b and cookie_a/cookie_b values */
2727 	swap(*addr_a, *addr_b);
2728 	swap(*cookie_a, *cookie_b);
2729 }
2730 
2731 static int bpf_kprobe_multi_addrs_cmp(const void *a, const void *b)
2732 {
2733 	const unsigned long *addr_a = a, *addr_b = b;
2734 
2735 	if (*addr_a == *addr_b)
2736 		return 0;
2737 	return *addr_a < *addr_b ? -1 : 1;
2738 }
2739 
2740 static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
2741 {
2742 	return bpf_kprobe_multi_addrs_cmp(a, b);
2743 }
2744 
2745 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2746 {
2747 	struct bpf_kprobe_multi_run_ctx *run_ctx;
2748 	struct bpf_kprobe_multi_link *link;
2749 	u64 *cookie, entry_ip;
2750 	unsigned long *addr;
2751 
2752 	if (WARN_ON_ONCE(!ctx))
2753 		return 0;
2754 	run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2755 	link = run_ctx->link;
2756 	if (!link->cookies)
2757 		return 0;
2758 	entry_ip = run_ctx->entry_ip;
2759 	addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
2760 		       bpf_kprobe_multi_addrs_cmp);
2761 	if (!addr)
2762 		return 0;
2763 	cookie = link->cookies + (addr - link->addrs);
2764 	return *cookie;
2765 }
2766 
2767 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2768 {
2769 	struct bpf_kprobe_multi_run_ctx *run_ctx;
2770 
2771 	run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2772 	return run_ctx->entry_ip;
2773 }
2774 
2775 static int
2776 kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
2777 			   unsigned long entry_ip, struct pt_regs *regs)
2778 {
2779 	struct bpf_kprobe_multi_run_ctx run_ctx = {
2780 		.link = link,
2781 		.entry_ip = entry_ip,
2782 	};
2783 	struct bpf_run_ctx *old_run_ctx;
2784 	int err;
2785 
2786 	if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
2787 		bpf_prog_inc_misses_counter(link->link.prog);
2788 		err = 0;
2789 		goto out;
2790 	}
2791 
2792 	migrate_disable();
2793 	rcu_read_lock();
2794 	old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
2795 	err = bpf_prog_run(link->link.prog, regs);
2796 	bpf_reset_run_ctx(old_run_ctx);
2797 	rcu_read_unlock();
2798 	migrate_enable();
2799 
2800  out:
2801 	__this_cpu_dec(bpf_prog_active);
2802 	return err;
2803 }
2804 
2805 static int
2806 kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
2807 			  unsigned long ret_ip, struct pt_regs *regs,
2808 			  void *data)
2809 {
2810 	struct bpf_kprobe_multi_link *link;
2811 
2812 	link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2813 	kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs);
2814 	return 0;
2815 }
2816 
2817 static void
2818 kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip,
2819 			       unsigned long ret_ip, struct pt_regs *regs,
2820 			       void *data)
2821 {
2822 	struct bpf_kprobe_multi_link *link;
2823 
2824 	link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2825 	kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs);
2826 }
2827 
2828 static int symbols_cmp_r(const void *a, const void *b, const void *priv)
2829 {
2830 	const char **str_a = (const char **) a;
2831 	const char **str_b = (const char **) b;
2832 
2833 	return strcmp(*str_a, *str_b);
2834 }
2835 
2836 struct multi_symbols_sort {
2837 	const char **funcs;
2838 	u64 *cookies;
2839 };
2840 
2841 static void symbols_swap_r(void *a, void *b, int size, const void *priv)
2842 {
2843 	const struct multi_symbols_sort *data = priv;
2844 	const char **name_a = a, **name_b = b;
2845 
2846 	swap(*name_a, *name_b);
2847 
2848 	/* If defined, swap also related cookies. */
2849 	if (data->cookies) {
2850 		u64 *cookie_a, *cookie_b;
2851 
2852 		cookie_a = data->cookies + (name_a - data->funcs);
2853 		cookie_b = data->cookies + (name_b - data->funcs);
2854 		swap(*cookie_a, *cookie_b);
2855 	}
2856 }
2857 
2858 struct modules_array {
2859 	struct module **mods;
2860 	int mods_cnt;
2861 	int mods_cap;
2862 };
2863 
2864 static int add_module(struct modules_array *arr, struct module *mod)
2865 {
2866 	struct module **mods;
2867 
2868 	if (arr->mods_cnt == arr->mods_cap) {
2869 		arr->mods_cap = max(16, arr->mods_cap * 3 / 2);
2870 		mods = krealloc_array(arr->mods, arr->mods_cap, sizeof(*mods), GFP_KERNEL);
2871 		if (!mods)
2872 			return -ENOMEM;
2873 		arr->mods = mods;
2874 	}
2875 
2876 	arr->mods[arr->mods_cnt] = mod;
2877 	arr->mods_cnt++;
2878 	return 0;
2879 }
2880 
2881 static bool has_module(struct modules_array *arr, struct module *mod)
2882 {
2883 	int i;
2884 
2885 	for (i = arr->mods_cnt - 1; i >= 0; i--) {
2886 		if (arr->mods[i] == mod)
2887 			return true;
2888 	}
2889 	return false;
2890 }
2891 
2892 static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u32 addrs_cnt)
2893 {
2894 	struct modules_array arr = {};
2895 	u32 i, err = 0;
2896 
2897 	for (i = 0; i < addrs_cnt; i++) {
2898 		struct module *mod;
2899 
2900 		preempt_disable();
2901 		mod = __module_address(addrs[i]);
2902 		/* Either no module or we it's already stored  */
2903 		if (!mod || has_module(&arr, mod)) {
2904 			preempt_enable();
2905 			continue;
2906 		}
2907 		if (!try_module_get(mod))
2908 			err = -EINVAL;
2909 		preempt_enable();
2910 		if (err)
2911 			break;
2912 		err = add_module(&arr, mod);
2913 		if (err) {
2914 			module_put(mod);
2915 			break;
2916 		}
2917 	}
2918 
2919 	/* We return either err < 0 in case of error, ... */
2920 	if (err) {
2921 		kprobe_multi_put_modules(arr.mods, arr.mods_cnt);
2922 		kfree(arr.mods);
2923 		return err;
2924 	}
2925 
2926 	/* or number of modules found if everything is ok. */
2927 	*mods = arr.mods;
2928 	return arr.mods_cnt;
2929 }
2930 
2931 static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt)
2932 {
2933 	u32 i;
2934 
2935 	for (i = 0; i < cnt; i++) {
2936 		if (!within_error_injection_list(addrs[i]))
2937 			return -EINVAL;
2938 	}
2939 	return 0;
2940 }
2941 
2942 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2943 {
2944 	struct bpf_kprobe_multi_link *link = NULL;
2945 	struct bpf_link_primer link_primer;
2946 	void __user *ucookies;
2947 	unsigned long *addrs;
2948 	u32 flags, cnt, size;
2949 	void __user *uaddrs;
2950 	u64 *cookies = NULL;
2951 	void __user *usyms;
2952 	int err;
2953 
2954 	/* no support for 32bit archs yet */
2955 	if (sizeof(u64) != sizeof(void *))
2956 		return -EOPNOTSUPP;
2957 
2958 	if (prog->expected_attach_type != BPF_TRACE_KPROBE_MULTI)
2959 		return -EINVAL;
2960 
2961 	flags = attr->link_create.kprobe_multi.flags;
2962 	if (flags & ~BPF_F_KPROBE_MULTI_RETURN)
2963 		return -EINVAL;
2964 
2965 	uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs);
2966 	usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms);
2967 	if (!!uaddrs == !!usyms)
2968 		return -EINVAL;
2969 
2970 	cnt = attr->link_create.kprobe_multi.cnt;
2971 	if (!cnt)
2972 		return -EINVAL;
2973 
2974 	size = cnt * sizeof(*addrs);
2975 	addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2976 	if (!addrs)
2977 		return -ENOMEM;
2978 
2979 	ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
2980 	if (ucookies) {
2981 		cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2982 		if (!cookies) {
2983 			err = -ENOMEM;
2984 			goto error;
2985 		}
2986 		if (copy_from_user(cookies, ucookies, size)) {
2987 			err = -EFAULT;
2988 			goto error;
2989 		}
2990 	}
2991 
2992 	if (uaddrs) {
2993 		if (copy_from_user(addrs, uaddrs, size)) {
2994 			err = -EFAULT;
2995 			goto error;
2996 		}
2997 	} else {
2998 		struct multi_symbols_sort data = {
2999 			.cookies = cookies,
3000 		};
3001 		struct user_syms us;
3002 
3003 		err = copy_user_syms(&us, usyms, cnt);
3004 		if (err)
3005 			goto error;
3006 
3007 		if (cookies)
3008 			data.funcs = us.syms;
3009 
3010 		sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r,
3011 		       symbols_swap_r, &data);
3012 
3013 		err = ftrace_lookup_symbols(us.syms, cnt, addrs);
3014 		free_user_syms(&us);
3015 		if (err)
3016 			goto error;
3017 	}
3018 
3019 	if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) {
3020 		err = -EINVAL;
3021 		goto error;
3022 	}
3023 
3024 	link = kzalloc(sizeof(*link), GFP_KERNEL);
3025 	if (!link) {
3026 		err = -ENOMEM;
3027 		goto error;
3028 	}
3029 
3030 	bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI,
3031 		      &bpf_kprobe_multi_link_lops, prog);
3032 
3033 	err = bpf_link_prime(&link->link, &link_primer);
3034 	if (err)
3035 		goto error;
3036 
3037 	if (flags & BPF_F_KPROBE_MULTI_RETURN)
3038 		link->fp.exit_handler = kprobe_multi_link_exit_handler;
3039 	else
3040 		link->fp.entry_handler = kprobe_multi_link_handler;
3041 
3042 	link->addrs = addrs;
3043 	link->cookies = cookies;
3044 	link->cnt = cnt;
3045 	link->flags = flags;
3046 
3047 	if (cookies) {
3048 		/*
3049 		 * Sorting addresses will trigger sorting cookies as well
3050 		 * (check bpf_kprobe_multi_cookie_swap). This way we can
3051 		 * find cookie based on the address in bpf_get_attach_cookie
3052 		 * helper.
3053 		 */
3054 		sort_r(addrs, cnt, sizeof(*addrs),
3055 		       bpf_kprobe_multi_cookie_cmp,
3056 		       bpf_kprobe_multi_cookie_swap,
3057 		       link);
3058 	}
3059 
3060 	err = get_modules_for_addrs(&link->mods, addrs, cnt);
3061 	if (err < 0) {
3062 		bpf_link_cleanup(&link_primer);
3063 		return err;
3064 	}
3065 	link->mods_cnt = err;
3066 
3067 	err = register_fprobe_ips(&link->fp, addrs, cnt);
3068 	if (err) {
3069 		kprobe_multi_put_modules(link->mods, link->mods_cnt);
3070 		bpf_link_cleanup(&link_primer);
3071 		return err;
3072 	}
3073 
3074 	return bpf_link_settle(&link_primer);
3075 
3076 error:
3077 	kfree(link);
3078 	kvfree(addrs);
3079 	kvfree(cookies);
3080 	return err;
3081 }
3082 #else /* !CONFIG_FPROBE */
3083 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3084 {
3085 	return -EOPNOTSUPP;
3086 }
3087 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
3088 {
3089 	return 0;
3090 }
3091 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3092 {
3093 	return 0;
3094 }
3095 #endif
3096 
3097 #ifdef CONFIG_UPROBES
3098 struct bpf_uprobe_multi_link;
3099 
3100 struct bpf_uprobe {
3101 	struct bpf_uprobe_multi_link *link;
3102 	loff_t offset;
3103 	unsigned long ref_ctr_offset;
3104 	u64 cookie;
3105 	struct uprobe_consumer consumer;
3106 };
3107 
3108 struct bpf_uprobe_multi_link {
3109 	struct path path;
3110 	struct bpf_link link;
3111 	u32 cnt;
3112 	u32 flags;
3113 	struct bpf_uprobe *uprobes;
3114 	struct task_struct *task;
3115 };
3116 
3117 struct bpf_uprobe_multi_run_ctx {
3118 	struct bpf_run_ctx run_ctx;
3119 	unsigned long entry_ip;
3120 	struct bpf_uprobe *uprobe;
3121 };
3122 
3123 static void bpf_uprobe_unregister(struct path *path, struct bpf_uprobe *uprobes,
3124 				  u32 cnt)
3125 {
3126 	u32 i;
3127 
3128 	for (i = 0; i < cnt; i++) {
3129 		uprobe_unregister(d_real_inode(path->dentry), uprobes[i].offset,
3130 				  &uprobes[i].consumer);
3131 	}
3132 }
3133 
3134 static void bpf_uprobe_multi_link_release(struct bpf_link *link)
3135 {
3136 	struct bpf_uprobe_multi_link *umulti_link;
3137 
3138 	umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3139 	bpf_uprobe_unregister(&umulti_link->path, umulti_link->uprobes, umulti_link->cnt);
3140 }
3141 
3142 static void bpf_uprobe_multi_link_dealloc(struct bpf_link *link)
3143 {
3144 	struct bpf_uprobe_multi_link *umulti_link;
3145 
3146 	umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3147 	if (umulti_link->task)
3148 		put_task_struct(umulti_link->task);
3149 	path_put(&umulti_link->path);
3150 	kvfree(umulti_link->uprobes);
3151 	kfree(umulti_link);
3152 }
3153 
3154 static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link,
3155 						struct bpf_link_info *info)
3156 {
3157 	u64 __user *uref_ctr_offsets = u64_to_user_ptr(info->uprobe_multi.ref_ctr_offsets);
3158 	u64 __user *ucookies = u64_to_user_ptr(info->uprobe_multi.cookies);
3159 	u64 __user *uoffsets = u64_to_user_ptr(info->uprobe_multi.offsets);
3160 	u64 __user *upath = u64_to_user_ptr(info->uprobe_multi.path);
3161 	u32 upath_size = info->uprobe_multi.path_size;
3162 	struct bpf_uprobe_multi_link *umulti_link;
3163 	u32 ucount = info->uprobe_multi.count;
3164 	int err = 0, i;
3165 	long left;
3166 
3167 	if (!upath ^ !upath_size)
3168 		return -EINVAL;
3169 
3170 	if ((uoffsets || uref_ctr_offsets || ucookies) && !ucount)
3171 		return -EINVAL;
3172 
3173 	umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
3174 	info->uprobe_multi.count = umulti_link->cnt;
3175 	info->uprobe_multi.flags = umulti_link->flags;
3176 	info->uprobe_multi.pid = umulti_link->task ?
3177 				 task_pid_nr_ns(umulti_link->task, task_active_pid_ns(current)) : 0;
3178 
3179 	if (upath) {
3180 		char *p, *buf;
3181 
3182 		upath_size = min_t(u32, upath_size, PATH_MAX);
3183 
3184 		buf = kmalloc(upath_size, GFP_KERNEL);
3185 		if (!buf)
3186 			return -ENOMEM;
3187 		p = d_path(&umulti_link->path, buf, upath_size);
3188 		if (IS_ERR(p)) {
3189 			kfree(buf);
3190 			return PTR_ERR(p);
3191 		}
3192 		upath_size = buf + upath_size - p;
3193 		left = copy_to_user(upath, p, upath_size);
3194 		kfree(buf);
3195 		if (left)
3196 			return -EFAULT;
3197 		info->uprobe_multi.path_size = upath_size;
3198 	}
3199 
3200 	if (!uoffsets && !ucookies && !uref_ctr_offsets)
3201 		return 0;
3202 
3203 	if (ucount < umulti_link->cnt)
3204 		err = -ENOSPC;
3205 	else
3206 		ucount = umulti_link->cnt;
3207 
3208 	for (i = 0; i < ucount; i++) {
3209 		if (uoffsets &&
3210 		    put_user(umulti_link->uprobes[i].offset, uoffsets + i))
3211 			return -EFAULT;
3212 		if (uref_ctr_offsets &&
3213 		    put_user(umulti_link->uprobes[i].ref_ctr_offset, uref_ctr_offsets + i))
3214 			return -EFAULT;
3215 		if (ucookies &&
3216 		    put_user(umulti_link->uprobes[i].cookie, ucookies + i))
3217 			return -EFAULT;
3218 	}
3219 
3220 	return err;
3221 }
3222 
3223 static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
3224 	.release = bpf_uprobe_multi_link_release,
3225 	.dealloc = bpf_uprobe_multi_link_dealloc,
3226 	.fill_link_info = bpf_uprobe_multi_link_fill_link_info,
3227 };
3228 
3229 static int uprobe_prog_run(struct bpf_uprobe *uprobe,
3230 			   unsigned long entry_ip,
3231 			   struct pt_regs *regs)
3232 {
3233 	struct bpf_uprobe_multi_link *link = uprobe->link;
3234 	struct bpf_uprobe_multi_run_ctx run_ctx = {
3235 		.entry_ip = entry_ip,
3236 		.uprobe = uprobe,
3237 	};
3238 	struct bpf_prog *prog = link->link.prog;
3239 	bool sleepable = prog->aux->sleepable;
3240 	struct bpf_run_ctx *old_run_ctx;
3241 	int err = 0;
3242 
3243 	if (link->task && current != link->task)
3244 		return 0;
3245 
3246 	if (sleepable)
3247 		rcu_read_lock_trace();
3248 	else
3249 		rcu_read_lock();
3250 
3251 	migrate_disable();
3252 
3253 	old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
3254 	err = bpf_prog_run(link->link.prog, regs);
3255 	bpf_reset_run_ctx(old_run_ctx);
3256 
3257 	migrate_enable();
3258 
3259 	if (sleepable)
3260 		rcu_read_unlock_trace();
3261 	else
3262 		rcu_read_unlock();
3263 	return err;
3264 }
3265 
3266 static bool
3267 uprobe_multi_link_filter(struct uprobe_consumer *con, enum uprobe_filter_ctx ctx,
3268 			 struct mm_struct *mm)
3269 {
3270 	struct bpf_uprobe *uprobe;
3271 
3272 	uprobe = container_of(con, struct bpf_uprobe, consumer);
3273 	return uprobe->link->task->mm == mm;
3274 }
3275 
3276 static int
3277 uprobe_multi_link_handler(struct uprobe_consumer *con, struct pt_regs *regs)
3278 {
3279 	struct bpf_uprobe *uprobe;
3280 
3281 	uprobe = container_of(con, struct bpf_uprobe, consumer);
3282 	return uprobe_prog_run(uprobe, instruction_pointer(regs), regs);
3283 }
3284 
3285 static int
3286 uprobe_multi_link_ret_handler(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs)
3287 {
3288 	struct bpf_uprobe *uprobe;
3289 
3290 	uprobe = container_of(con, struct bpf_uprobe, consumer);
3291 	return uprobe_prog_run(uprobe, func, regs);
3292 }
3293 
3294 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3295 {
3296 	struct bpf_uprobe_multi_run_ctx *run_ctx;
3297 
3298 	run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
3299 	return run_ctx->entry_ip;
3300 }
3301 
3302 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
3303 {
3304 	struct bpf_uprobe_multi_run_ctx *run_ctx;
3305 
3306 	run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx);
3307 	return run_ctx->uprobe->cookie;
3308 }
3309 
3310 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3311 {
3312 	struct bpf_uprobe_multi_link *link = NULL;
3313 	unsigned long __user *uref_ctr_offsets;
3314 	struct bpf_link_primer link_primer;
3315 	struct bpf_uprobe *uprobes = NULL;
3316 	struct task_struct *task = NULL;
3317 	unsigned long __user *uoffsets;
3318 	u64 __user *ucookies;
3319 	void __user *upath;
3320 	u32 flags, cnt, i;
3321 	struct path path;
3322 	char *name;
3323 	pid_t pid;
3324 	int err;
3325 
3326 	/* no support for 32bit archs yet */
3327 	if (sizeof(u64) != sizeof(void *))
3328 		return -EOPNOTSUPP;
3329 
3330 	if (prog->expected_attach_type != BPF_TRACE_UPROBE_MULTI)
3331 		return -EINVAL;
3332 
3333 	flags = attr->link_create.uprobe_multi.flags;
3334 	if (flags & ~BPF_F_UPROBE_MULTI_RETURN)
3335 		return -EINVAL;
3336 
3337 	/*
3338 	 * path, offsets and cnt are mandatory,
3339 	 * ref_ctr_offsets and cookies are optional
3340 	 */
3341 	upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path);
3342 	uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets);
3343 	cnt = attr->link_create.uprobe_multi.cnt;
3344 
3345 	if (!upath || !uoffsets || !cnt)
3346 		return -EINVAL;
3347 
3348 	uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets);
3349 	ucookies = u64_to_user_ptr(attr->link_create.uprobe_multi.cookies);
3350 
3351 	name = strndup_user(upath, PATH_MAX);
3352 	if (IS_ERR(name)) {
3353 		err = PTR_ERR(name);
3354 		return err;
3355 	}
3356 
3357 	err = kern_path(name, LOOKUP_FOLLOW, &path);
3358 	kfree(name);
3359 	if (err)
3360 		return err;
3361 
3362 	if (!d_is_reg(path.dentry)) {
3363 		err = -EBADF;
3364 		goto error_path_put;
3365 	}
3366 
3367 	pid = attr->link_create.uprobe_multi.pid;
3368 	if (pid) {
3369 		rcu_read_lock();
3370 		task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
3371 		rcu_read_unlock();
3372 		if (!task) {
3373 			err = -ESRCH;
3374 			goto error_path_put;
3375 		}
3376 	}
3377 
3378 	err = -ENOMEM;
3379 
3380 	link = kzalloc(sizeof(*link), GFP_KERNEL);
3381 	uprobes = kvcalloc(cnt, sizeof(*uprobes), GFP_KERNEL);
3382 
3383 	if (!uprobes || !link)
3384 		goto error_free;
3385 
3386 	for (i = 0; i < cnt; i++) {
3387 		if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) {
3388 			err = -EFAULT;
3389 			goto error_free;
3390 		}
3391 		if (uref_ctr_offsets && __get_user(uprobes[i].ref_ctr_offset, uref_ctr_offsets + i)) {
3392 			err = -EFAULT;
3393 			goto error_free;
3394 		}
3395 		if (__get_user(uprobes[i].offset, uoffsets + i)) {
3396 			err = -EFAULT;
3397 			goto error_free;
3398 		}
3399 
3400 		uprobes[i].link = link;
3401 
3402 		if (flags & BPF_F_UPROBE_MULTI_RETURN)
3403 			uprobes[i].consumer.ret_handler = uprobe_multi_link_ret_handler;
3404 		else
3405 			uprobes[i].consumer.handler = uprobe_multi_link_handler;
3406 
3407 		if (pid)
3408 			uprobes[i].consumer.filter = uprobe_multi_link_filter;
3409 	}
3410 
3411 	link->cnt = cnt;
3412 	link->uprobes = uprobes;
3413 	link->path = path;
3414 	link->task = task;
3415 	link->flags = flags;
3416 
3417 	bpf_link_init(&link->link, BPF_LINK_TYPE_UPROBE_MULTI,
3418 		      &bpf_uprobe_multi_link_lops, prog);
3419 
3420 	for (i = 0; i < cnt; i++) {
3421 		err = uprobe_register_refctr(d_real_inode(link->path.dentry),
3422 					     uprobes[i].offset,
3423 					     uprobes[i].ref_ctr_offset,
3424 					     &uprobes[i].consumer);
3425 		if (err) {
3426 			bpf_uprobe_unregister(&path, uprobes, i);
3427 			goto error_free;
3428 		}
3429 	}
3430 
3431 	err = bpf_link_prime(&link->link, &link_primer);
3432 	if (err)
3433 		goto error_free;
3434 
3435 	return bpf_link_settle(&link_primer);
3436 
3437 error_free:
3438 	kvfree(uprobes);
3439 	kfree(link);
3440 	if (task)
3441 		put_task_struct(task);
3442 error_path_put:
3443 	path_put(&path);
3444 	return err;
3445 }
3446 #else /* !CONFIG_UPROBES */
3447 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3448 {
3449 	return -EOPNOTSUPP;
3450 }
3451 static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx)
3452 {
3453 	return 0;
3454 }
3455 static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
3456 {
3457 	return 0;
3458 }
3459 #endif /* CONFIG_UPROBES */
3460