xref: /linux/kernel/bpf/helpers.c (revision de8c12110a130337c8e7e7b8250de0580e644dee)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/rcupdate.h>
6 #include <linux/random.h>
7 #include <linux/smp.h>
8 #include <linux/topology.h>
9 #include <linux/ktime.h>
10 #include <linux/sched.h>
11 #include <linux/uidgid.h>
12 #include <linux/filter.h>
13 #include <linux/ctype.h>
14 #include <linux/jiffies.h>
15 #include <linux/pid_namespace.h>
16 #include <linux/proc_ns.h>
17 
18 #include "../../lib/kstrtox.h"
19 
20 /* If kernel subsystem is allowing eBPF programs to call this function,
21  * inside its own verifier_ops->get_func_proto() callback it should return
22  * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments
23  *
24  * Different map implementations will rely on rcu in map methods
25  * lookup/update/delete, therefore eBPF programs must run under rcu lock
26  * if program is allowed to access maps, so check rcu_read_lock_held in
27  * all three functions.
28  */
29 BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key)
30 {
31 	WARN_ON_ONCE(!rcu_read_lock_held());
32 	return (unsigned long) map->ops->map_lookup_elem(map, key);
33 }
34 
35 const struct bpf_func_proto bpf_map_lookup_elem_proto = {
36 	.func		= bpf_map_lookup_elem,
37 	.gpl_only	= false,
38 	.pkt_access	= true,
39 	.ret_type	= RET_PTR_TO_MAP_VALUE_OR_NULL,
40 	.arg1_type	= ARG_CONST_MAP_PTR,
41 	.arg2_type	= ARG_PTR_TO_MAP_KEY,
42 };
43 
44 BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key,
45 	   void *, value, u64, flags)
46 {
47 	WARN_ON_ONCE(!rcu_read_lock_held());
48 	return map->ops->map_update_elem(map, key, value, flags);
49 }
50 
51 const struct bpf_func_proto bpf_map_update_elem_proto = {
52 	.func		= bpf_map_update_elem,
53 	.gpl_only	= false,
54 	.pkt_access	= true,
55 	.ret_type	= RET_INTEGER,
56 	.arg1_type	= ARG_CONST_MAP_PTR,
57 	.arg2_type	= ARG_PTR_TO_MAP_KEY,
58 	.arg3_type	= ARG_PTR_TO_MAP_VALUE,
59 	.arg4_type	= ARG_ANYTHING,
60 };
61 
62 BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key)
63 {
64 	WARN_ON_ONCE(!rcu_read_lock_held());
65 	return map->ops->map_delete_elem(map, key);
66 }
67 
68 const struct bpf_func_proto bpf_map_delete_elem_proto = {
69 	.func		= bpf_map_delete_elem,
70 	.gpl_only	= false,
71 	.pkt_access	= true,
72 	.ret_type	= RET_INTEGER,
73 	.arg1_type	= ARG_CONST_MAP_PTR,
74 	.arg2_type	= ARG_PTR_TO_MAP_KEY,
75 };
76 
77 BPF_CALL_3(bpf_map_push_elem, struct bpf_map *, map, void *, value, u64, flags)
78 {
79 	return map->ops->map_push_elem(map, value, flags);
80 }
81 
82 const struct bpf_func_proto bpf_map_push_elem_proto = {
83 	.func		= bpf_map_push_elem,
84 	.gpl_only	= false,
85 	.pkt_access	= true,
86 	.ret_type	= RET_INTEGER,
87 	.arg1_type	= ARG_CONST_MAP_PTR,
88 	.arg2_type	= ARG_PTR_TO_MAP_VALUE,
89 	.arg3_type	= ARG_ANYTHING,
90 };
91 
92 BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value)
93 {
94 	return map->ops->map_pop_elem(map, value);
95 }
96 
97 const struct bpf_func_proto bpf_map_pop_elem_proto = {
98 	.func		= bpf_map_pop_elem,
99 	.gpl_only	= false,
100 	.ret_type	= RET_INTEGER,
101 	.arg1_type	= ARG_CONST_MAP_PTR,
102 	.arg2_type	= ARG_PTR_TO_UNINIT_MAP_VALUE,
103 };
104 
105 BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value)
106 {
107 	return map->ops->map_peek_elem(map, value);
108 }
109 
110 const struct bpf_func_proto bpf_map_peek_elem_proto = {
111 	.func		= bpf_map_peek_elem,
112 	.gpl_only	= false,
113 	.ret_type	= RET_INTEGER,
114 	.arg1_type	= ARG_CONST_MAP_PTR,
115 	.arg2_type	= ARG_PTR_TO_UNINIT_MAP_VALUE,
116 };
117 
118 const struct bpf_func_proto bpf_get_prandom_u32_proto = {
119 	.func		= bpf_user_rnd_u32,
120 	.gpl_only	= false,
121 	.ret_type	= RET_INTEGER,
122 };
123 
124 BPF_CALL_0(bpf_get_smp_processor_id)
125 {
126 	return smp_processor_id();
127 }
128 
129 const struct bpf_func_proto bpf_get_smp_processor_id_proto = {
130 	.func		= bpf_get_smp_processor_id,
131 	.gpl_only	= false,
132 	.ret_type	= RET_INTEGER,
133 };
134 
135 BPF_CALL_0(bpf_get_numa_node_id)
136 {
137 	return numa_node_id();
138 }
139 
140 const struct bpf_func_proto bpf_get_numa_node_id_proto = {
141 	.func		= bpf_get_numa_node_id,
142 	.gpl_only	= false,
143 	.ret_type	= RET_INTEGER,
144 };
145 
146 BPF_CALL_0(bpf_ktime_get_ns)
147 {
148 	/* NMI safe access to clock monotonic */
149 	return ktime_get_mono_fast_ns();
150 }
151 
152 const struct bpf_func_proto bpf_ktime_get_ns_proto = {
153 	.func		= bpf_ktime_get_ns,
154 	.gpl_only	= false,
155 	.ret_type	= RET_INTEGER,
156 };
157 
158 BPF_CALL_0(bpf_ktime_get_boot_ns)
159 {
160 	/* NMI safe access to clock boottime */
161 	return ktime_get_boot_fast_ns();
162 }
163 
164 const struct bpf_func_proto bpf_ktime_get_boot_ns_proto = {
165 	.func		= bpf_ktime_get_boot_ns,
166 	.gpl_only	= false,
167 	.ret_type	= RET_INTEGER,
168 };
169 
170 BPF_CALL_0(bpf_ktime_get_coarse_ns)
171 {
172 	return ktime_get_coarse_ns();
173 }
174 
175 const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto = {
176 	.func		= bpf_ktime_get_coarse_ns,
177 	.gpl_only	= false,
178 	.ret_type	= RET_INTEGER,
179 };
180 
181 BPF_CALL_0(bpf_get_current_pid_tgid)
182 {
183 	struct task_struct *task = current;
184 
185 	if (unlikely(!task))
186 		return -EINVAL;
187 
188 	return (u64) task->tgid << 32 | task->pid;
189 }
190 
191 const struct bpf_func_proto bpf_get_current_pid_tgid_proto = {
192 	.func		= bpf_get_current_pid_tgid,
193 	.gpl_only	= false,
194 	.ret_type	= RET_INTEGER,
195 };
196 
197 BPF_CALL_0(bpf_get_current_uid_gid)
198 {
199 	struct task_struct *task = current;
200 	kuid_t uid;
201 	kgid_t gid;
202 
203 	if (unlikely(!task))
204 		return -EINVAL;
205 
206 	current_uid_gid(&uid, &gid);
207 	return (u64) from_kgid(&init_user_ns, gid) << 32 |
208 		     from_kuid(&init_user_ns, uid);
209 }
210 
211 const struct bpf_func_proto bpf_get_current_uid_gid_proto = {
212 	.func		= bpf_get_current_uid_gid,
213 	.gpl_only	= false,
214 	.ret_type	= RET_INTEGER,
215 };
216 
217 BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
218 {
219 	struct task_struct *task = current;
220 
221 	if (unlikely(!task))
222 		goto err_clear;
223 
224 	strncpy(buf, task->comm, size);
225 
226 	/* Verifier guarantees that size > 0. For task->comm exceeding
227 	 * size, guarantee that buf is %NUL-terminated. Unconditionally
228 	 * done here to save the size test.
229 	 */
230 	buf[size - 1] = 0;
231 	return 0;
232 err_clear:
233 	memset(buf, 0, size);
234 	return -EINVAL;
235 }
236 
237 const struct bpf_func_proto bpf_get_current_comm_proto = {
238 	.func		= bpf_get_current_comm,
239 	.gpl_only	= false,
240 	.ret_type	= RET_INTEGER,
241 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
242 	.arg2_type	= ARG_CONST_SIZE,
243 };
244 
245 #if defined(CONFIG_QUEUED_SPINLOCKS) || defined(CONFIG_BPF_ARCH_SPINLOCK)
246 
247 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
248 {
249 	arch_spinlock_t *l = (void *)lock;
250 	union {
251 		__u32 val;
252 		arch_spinlock_t lock;
253 	} u = { .lock = __ARCH_SPIN_LOCK_UNLOCKED };
254 
255 	compiletime_assert(u.val == 0, "__ARCH_SPIN_LOCK_UNLOCKED not 0");
256 	BUILD_BUG_ON(sizeof(*l) != sizeof(__u32));
257 	BUILD_BUG_ON(sizeof(*lock) != sizeof(__u32));
258 	arch_spin_lock(l);
259 }
260 
261 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
262 {
263 	arch_spinlock_t *l = (void *)lock;
264 
265 	arch_spin_unlock(l);
266 }
267 
268 #else
269 
270 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
271 {
272 	atomic_t *l = (void *)lock;
273 
274 	BUILD_BUG_ON(sizeof(*l) != sizeof(*lock));
275 	do {
276 		atomic_cond_read_relaxed(l, !VAL);
277 	} while (atomic_xchg(l, 1));
278 }
279 
280 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
281 {
282 	atomic_t *l = (void *)lock;
283 
284 	atomic_set_release(l, 0);
285 }
286 
287 #endif
288 
289 static DEFINE_PER_CPU(unsigned long, irqsave_flags);
290 
291 notrace BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
292 {
293 	unsigned long flags;
294 
295 	local_irq_save(flags);
296 	__bpf_spin_lock(lock);
297 	__this_cpu_write(irqsave_flags, flags);
298 	return 0;
299 }
300 
301 const struct bpf_func_proto bpf_spin_lock_proto = {
302 	.func		= bpf_spin_lock,
303 	.gpl_only	= false,
304 	.ret_type	= RET_VOID,
305 	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
306 };
307 
308 notrace BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
309 {
310 	unsigned long flags;
311 
312 	flags = __this_cpu_read(irqsave_flags);
313 	__bpf_spin_unlock(lock);
314 	local_irq_restore(flags);
315 	return 0;
316 }
317 
318 const struct bpf_func_proto bpf_spin_unlock_proto = {
319 	.func		= bpf_spin_unlock,
320 	.gpl_only	= false,
321 	.ret_type	= RET_VOID,
322 	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
323 };
324 
325 void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
326 			   bool lock_src)
327 {
328 	struct bpf_spin_lock *lock;
329 
330 	if (lock_src)
331 		lock = src + map->spin_lock_off;
332 	else
333 		lock = dst + map->spin_lock_off;
334 	preempt_disable();
335 	____bpf_spin_lock(lock);
336 	copy_map_value(map, dst, src);
337 	____bpf_spin_unlock(lock);
338 	preempt_enable();
339 }
340 
341 BPF_CALL_0(bpf_jiffies64)
342 {
343 	return get_jiffies_64();
344 }
345 
346 const struct bpf_func_proto bpf_jiffies64_proto = {
347 	.func		= bpf_jiffies64,
348 	.gpl_only	= false,
349 	.ret_type	= RET_INTEGER,
350 };
351 
352 #ifdef CONFIG_CGROUPS
353 BPF_CALL_0(bpf_get_current_cgroup_id)
354 {
355 	struct cgroup *cgrp = task_dfl_cgroup(current);
356 
357 	return cgroup_id(cgrp);
358 }
359 
360 const struct bpf_func_proto bpf_get_current_cgroup_id_proto = {
361 	.func		= bpf_get_current_cgroup_id,
362 	.gpl_only	= false,
363 	.ret_type	= RET_INTEGER,
364 };
365 
366 BPF_CALL_1(bpf_get_current_ancestor_cgroup_id, int, ancestor_level)
367 {
368 	struct cgroup *cgrp = task_dfl_cgroup(current);
369 	struct cgroup *ancestor;
370 
371 	ancestor = cgroup_ancestor(cgrp, ancestor_level);
372 	if (!ancestor)
373 		return 0;
374 	return cgroup_id(ancestor);
375 }
376 
377 const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto = {
378 	.func		= bpf_get_current_ancestor_cgroup_id,
379 	.gpl_only	= false,
380 	.ret_type	= RET_INTEGER,
381 	.arg1_type	= ARG_ANYTHING,
382 };
383 
384 #ifdef CONFIG_CGROUP_BPF
385 DECLARE_PER_CPU(struct bpf_cgroup_storage_info,
386 		bpf_cgroup_storage_info[BPF_CGROUP_STORAGE_NEST_MAX]);
387 
388 BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
389 {
390 	/* flags argument is not used now,
391 	 * but provides an ability to extend the API.
392 	 * verifier checks that its value is correct.
393 	 */
394 	enum bpf_cgroup_storage_type stype = cgroup_storage_type(map);
395 	struct bpf_cgroup_storage *storage = NULL;
396 	void *ptr;
397 	int i;
398 
399 	for (i = 0; i < BPF_CGROUP_STORAGE_NEST_MAX; i++) {
400 		if (unlikely(this_cpu_read(bpf_cgroup_storage_info[i].task) != current))
401 			continue;
402 
403 		storage = this_cpu_read(bpf_cgroup_storage_info[i].storage[stype]);
404 		break;
405 	}
406 
407 	if (stype == BPF_CGROUP_STORAGE_SHARED)
408 		ptr = &READ_ONCE(storage->buf)->data[0];
409 	else
410 		ptr = this_cpu_ptr(storage->percpu_buf);
411 
412 	return (unsigned long)ptr;
413 }
414 
415 const struct bpf_func_proto bpf_get_local_storage_proto = {
416 	.func		= bpf_get_local_storage,
417 	.gpl_only	= false,
418 	.ret_type	= RET_PTR_TO_MAP_VALUE,
419 	.arg1_type	= ARG_CONST_MAP_PTR,
420 	.arg2_type	= ARG_ANYTHING,
421 };
422 #endif
423 
424 #define BPF_STRTOX_BASE_MASK 0x1F
425 
426 static int __bpf_strtoull(const char *buf, size_t buf_len, u64 flags,
427 			  unsigned long long *res, bool *is_negative)
428 {
429 	unsigned int base = flags & BPF_STRTOX_BASE_MASK;
430 	const char *cur_buf = buf;
431 	size_t cur_len = buf_len;
432 	unsigned int consumed;
433 	size_t val_len;
434 	char str[64];
435 
436 	if (!buf || !buf_len || !res || !is_negative)
437 		return -EINVAL;
438 
439 	if (base != 0 && base != 8 && base != 10 && base != 16)
440 		return -EINVAL;
441 
442 	if (flags & ~BPF_STRTOX_BASE_MASK)
443 		return -EINVAL;
444 
445 	while (cur_buf < buf + buf_len && isspace(*cur_buf))
446 		++cur_buf;
447 
448 	*is_negative = (cur_buf < buf + buf_len && *cur_buf == '-');
449 	if (*is_negative)
450 		++cur_buf;
451 
452 	consumed = cur_buf - buf;
453 	cur_len -= consumed;
454 	if (!cur_len)
455 		return -EINVAL;
456 
457 	cur_len = min(cur_len, sizeof(str) - 1);
458 	memcpy(str, cur_buf, cur_len);
459 	str[cur_len] = '\0';
460 	cur_buf = str;
461 
462 	cur_buf = _parse_integer_fixup_radix(cur_buf, &base);
463 	val_len = _parse_integer(cur_buf, base, res);
464 
465 	if (val_len & KSTRTOX_OVERFLOW)
466 		return -ERANGE;
467 
468 	if (val_len == 0)
469 		return -EINVAL;
470 
471 	cur_buf += val_len;
472 	consumed += cur_buf - str;
473 
474 	return consumed;
475 }
476 
477 static int __bpf_strtoll(const char *buf, size_t buf_len, u64 flags,
478 			 long long *res)
479 {
480 	unsigned long long _res;
481 	bool is_negative;
482 	int err;
483 
484 	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
485 	if (err < 0)
486 		return err;
487 	if (is_negative) {
488 		if ((long long)-_res > 0)
489 			return -ERANGE;
490 		*res = -_res;
491 	} else {
492 		if ((long long)_res < 0)
493 			return -ERANGE;
494 		*res = _res;
495 	}
496 	return err;
497 }
498 
499 BPF_CALL_4(bpf_strtol, const char *, buf, size_t, buf_len, u64, flags,
500 	   long *, res)
501 {
502 	long long _res;
503 	int err;
504 
505 	err = __bpf_strtoll(buf, buf_len, flags, &_res);
506 	if (err < 0)
507 		return err;
508 	if (_res != (long)_res)
509 		return -ERANGE;
510 	*res = _res;
511 	return err;
512 }
513 
514 const struct bpf_func_proto bpf_strtol_proto = {
515 	.func		= bpf_strtol,
516 	.gpl_only	= false,
517 	.ret_type	= RET_INTEGER,
518 	.arg1_type	= ARG_PTR_TO_MEM,
519 	.arg2_type	= ARG_CONST_SIZE,
520 	.arg3_type	= ARG_ANYTHING,
521 	.arg4_type	= ARG_PTR_TO_LONG,
522 };
523 
524 BPF_CALL_4(bpf_strtoul, const char *, buf, size_t, buf_len, u64, flags,
525 	   unsigned long *, res)
526 {
527 	unsigned long long _res;
528 	bool is_negative;
529 	int err;
530 
531 	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
532 	if (err < 0)
533 		return err;
534 	if (is_negative)
535 		return -EINVAL;
536 	if (_res != (unsigned long)_res)
537 		return -ERANGE;
538 	*res = _res;
539 	return err;
540 }
541 
542 const struct bpf_func_proto bpf_strtoul_proto = {
543 	.func		= bpf_strtoul,
544 	.gpl_only	= false,
545 	.ret_type	= RET_INTEGER,
546 	.arg1_type	= ARG_PTR_TO_MEM,
547 	.arg2_type	= ARG_CONST_SIZE,
548 	.arg3_type	= ARG_ANYTHING,
549 	.arg4_type	= ARG_PTR_TO_LONG,
550 };
551 #endif
552 
553 BPF_CALL_4(bpf_get_ns_current_pid_tgid, u64, dev, u64, ino,
554 	   struct bpf_pidns_info *, nsdata, u32, size)
555 {
556 	struct task_struct *task = current;
557 	struct pid_namespace *pidns;
558 	int err = -EINVAL;
559 
560 	if (unlikely(size != sizeof(struct bpf_pidns_info)))
561 		goto clear;
562 
563 	if (unlikely((u64)(dev_t)dev != dev))
564 		goto clear;
565 
566 	if (unlikely(!task))
567 		goto clear;
568 
569 	pidns = task_active_pid_ns(task);
570 	if (unlikely(!pidns)) {
571 		err = -ENOENT;
572 		goto clear;
573 	}
574 
575 	if (!ns_match(&pidns->ns, (dev_t)dev, ino))
576 		goto clear;
577 
578 	nsdata->pid = task_pid_nr_ns(task, pidns);
579 	nsdata->tgid = task_tgid_nr_ns(task, pidns);
580 	return 0;
581 clear:
582 	memset((void *)nsdata, 0, (size_t) size);
583 	return err;
584 }
585 
586 const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto = {
587 	.func		= bpf_get_ns_current_pid_tgid,
588 	.gpl_only	= false,
589 	.ret_type	= RET_INTEGER,
590 	.arg1_type	= ARG_ANYTHING,
591 	.arg2_type	= ARG_ANYTHING,
592 	.arg3_type      = ARG_PTR_TO_UNINIT_MEM,
593 	.arg4_type      = ARG_CONST_SIZE,
594 };
595 
596 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
597 	.func		= bpf_get_raw_cpu_id,
598 	.gpl_only	= false,
599 	.ret_type	= RET_INTEGER,
600 };
601 
602 BPF_CALL_5(bpf_event_output_data, void *, ctx, struct bpf_map *, map,
603 	   u64, flags, void *, data, u64, size)
604 {
605 	if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
606 		return -EINVAL;
607 
608 	return bpf_event_output(map, flags, data, size, NULL, 0, NULL);
609 }
610 
611 const struct bpf_func_proto bpf_event_output_data_proto =  {
612 	.func		= bpf_event_output_data,
613 	.gpl_only       = true,
614 	.ret_type       = RET_INTEGER,
615 	.arg1_type      = ARG_PTR_TO_CTX,
616 	.arg2_type      = ARG_CONST_MAP_PTR,
617 	.arg3_type      = ARG_ANYTHING,
618 	.arg4_type      = ARG_PTR_TO_MEM,
619 	.arg5_type      = ARG_CONST_SIZE_OR_ZERO,
620 };
621 
622 BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size,
623 	   const void __user *, user_ptr)
624 {
625 	int ret = copy_from_user(dst, user_ptr, size);
626 
627 	if (unlikely(ret)) {
628 		memset(dst, 0, size);
629 		ret = -EFAULT;
630 	}
631 
632 	return ret;
633 }
634 
635 const struct bpf_func_proto bpf_copy_from_user_proto = {
636 	.func		= bpf_copy_from_user,
637 	.gpl_only	= false,
638 	.ret_type	= RET_INTEGER,
639 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
640 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
641 	.arg3_type	= ARG_ANYTHING,
642 };
643 
644 BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu)
645 {
646 	if (cpu >= nr_cpu_ids)
647 		return (unsigned long)NULL;
648 
649 	return (unsigned long)per_cpu_ptr((const void __percpu *)ptr, cpu);
650 }
651 
652 const struct bpf_func_proto bpf_per_cpu_ptr_proto = {
653 	.func		= bpf_per_cpu_ptr,
654 	.gpl_only	= false,
655 	.ret_type	= RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL,
656 	.arg1_type	= ARG_PTR_TO_PERCPU_BTF_ID,
657 	.arg2_type	= ARG_ANYTHING,
658 };
659 
660 BPF_CALL_1(bpf_this_cpu_ptr, const void *, percpu_ptr)
661 {
662 	return (unsigned long)this_cpu_ptr((const void __percpu *)percpu_ptr);
663 }
664 
665 const struct bpf_func_proto bpf_this_cpu_ptr_proto = {
666 	.func		= bpf_this_cpu_ptr,
667 	.gpl_only	= false,
668 	.ret_type	= RET_PTR_TO_MEM_OR_BTF_ID,
669 	.arg1_type	= ARG_PTR_TO_PERCPU_BTF_ID,
670 };
671 
672 const struct bpf_func_proto bpf_get_current_task_proto __weak;
673 const struct bpf_func_proto bpf_probe_read_user_proto __weak;
674 const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
675 const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
676 const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
677 
678 const struct bpf_func_proto *
679 bpf_base_func_proto(enum bpf_func_id func_id)
680 {
681 	switch (func_id) {
682 	case BPF_FUNC_map_lookup_elem:
683 		return &bpf_map_lookup_elem_proto;
684 	case BPF_FUNC_map_update_elem:
685 		return &bpf_map_update_elem_proto;
686 	case BPF_FUNC_map_delete_elem:
687 		return &bpf_map_delete_elem_proto;
688 	case BPF_FUNC_map_push_elem:
689 		return &bpf_map_push_elem_proto;
690 	case BPF_FUNC_map_pop_elem:
691 		return &bpf_map_pop_elem_proto;
692 	case BPF_FUNC_map_peek_elem:
693 		return &bpf_map_peek_elem_proto;
694 	case BPF_FUNC_get_prandom_u32:
695 		return &bpf_get_prandom_u32_proto;
696 	case BPF_FUNC_get_smp_processor_id:
697 		return &bpf_get_raw_smp_processor_id_proto;
698 	case BPF_FUNC_get_numa_node_id:
699 		return &bpf_get_numa_node_id_proto;
700 	case BPF_FUNC_tail_call:
701 		return &bpf_tail_call_proto;
702 	case BPF_FUNC_ktime_get_ns:
703 		return &bpf_ktime_get_ns_proto;
704 	case BPF_FUNC_ktime_get_boot_ns:
705 		return &bpf_ktime_get_boot_ns_proto;
706 	case BPF_FUNC_ktime_get_coarse_ns:
707 		return &bpf_ktime_get_coarse_ns_proto;
708 	case BPF_FUNC_ringbuf_output:
709 		return &bpf_ringbuf_output_proto;
710 	case BPF_FUNC_ringbuf_reserve:
711 		return &bpf_ringbuf_reserve_proto;
712 	case BPF_FUNC_ringbuf_submit:
713 		return &bpf_ringbuf_submit_proto;
714 	case BPF_FUNC_ringbuf_discard:
715 		return &bpf_ringbuf_discard_proto;
716 	case BPF_FUNC_ringbuf_query:
717 		return &bpf_ringbuf_query_proto;
718 	case BPF_FUNC_for_each_map_elem:
719 		return &bpf_for_each_map_elem_proto;
720 	default:
721 		break;
722 	}
723 
724 	if (!bpf_capable())
725 		return NULL;
726 
727 	switch (func_id) {
728 	case BPF_FUNC_spin_lock:
729 		return &bpf_spin_lock_proto;
730 	case BPF_FUNC_spin_unlock:
731 		return &bpf_spin_unlock_proto;
732 	case BPF_FUNC_jiffies64:
733 		return &bpf_jiffies64_proto;
734 	case BPF_FUNC_per_cpu_ptr:
735 		return &bpf_per_cpu_ptr_proto;
736 	case BPF_FUNC_this_cpu_ptr:
737 		return &bpf_this_cpu_ptr_proto;
738 	default:
739 		break;
740 	}
741 
742 	if (!perfmon_capable())
743 		return NULL;
744 
745 	switch (func_id) {
746 	case BPF_FUNC_trace_printk:
747 		return bpf_get_trace_printk_proto();
748 	case BPF_FUNC_get_current_task:
749 		return &bpf_get_current_task_proto;
750 	case BPF_FUNC_probe_read_user:
751 		return &bpf_probe_read_user_proto;
752 	case BPF_FUNC_probe_read_kernel:
753 		return &bpf_probe_read_kernel_proto;
754 	case BPF_FUNC_probe_read_user_str:
755 		return &bpf_probe_read_user_str_proto;
756 	case BPF_FUNC_probe_read_kernel_str:
757 		return &bpf_probe_read_kernel_str_proto;
758 	case BPF_FUNC_snprintf_btf:
759 		return &bpf_snprintf_btf_proto;
760 	default:
761 		return NULL;
762 	}
763 }
764