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  */
BPF_CALL_2(bpf_map_lookup_elem,struct bpf_map *,map,void *,key)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 
BPF_CALL_4(bpf_map_update_elem,struct bpf_map *,map,void *,key,void *,value,u64,flags)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 
BPF_CALL_2(bpf_map_delete_elem,struct bpf_map *,map,void *,key)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 
BPF_CALL_3(bpf_map_push_elem,struct bpf_map *,map,void *,value,u64,flags)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 
BPF_CALL_2(bpf_map_pop_elem,struct bpf_map *,map,void *,value)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 
BPF_CALL_2(bpf_map_peek_elem,struct bpf_map *,map,void *,value)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_pop_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 
BPF_CALL_0(bpf_get_smp_processor_id)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 
BPF_CALL_0(bpf_get_numa_node_id)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 
BPF_CALL_0(bpf_ktime_get_ns)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 
BPF_CALL_0(bpf_ktime_get_boot_ns)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 
BPF_CALL_0(bpf_get_current_pid_tgid)170 BPF_CALL_0(bpf_get_current_pid_tgid)
171 {
172 	struct task_struct *task = current;
173 
174 	if (unlikely(!task))
175 		return -EINVAL;
176 
177 	return (u64) task->tgid << 32 | task->pid;
178 }
179 
180 const struct bpf_func_proto bpf_get_current_pid_tgid_proto = {
181 	.func		= bpf_get_current_pid_tgid,
182 	.gpl_only	= false,
183 	.ret_type	= RET_INTEGER,
184 };
185 
BPF_CALL_0(bpf_get_current_uid_gid)186 BPF_CALL_0(bpf_get_current_uid_gid)
187 {
188 	struct task_struct *task = current;
189 	kuid_t uid;
190 	kgid_t gid;
191 
192 	if (unlikely(!task))
193 		return -EINVAL;
194 
195 	current_uid_gid(&uid, &gid);
196 	return (u64) from_kgid(&init_user_ns, gid) << 32 |
197 		     from_kuid(&init_user_ns, uid);
198 }
199 
200 const struct bpf_func_proto bpf_get_current_uid_gid_proto = {
201 	.func		= bpf_get_current_uid_gid,
202 	.gpl_only	= false,
203 	.ret_type	= RET_INTEGER,
204 };
205 
BPF_CALL_2(bpf_get_current_comm,char *,buf,u32,size)206 BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
207 {
208 	struct task_struct *task = current;
209 
210 	if (unlikely(!task))
211 		goto err_clear;
212 
213 	strncpy(buf, task->comm, size);
214 
215 	/* Verifier guarantees that size > 0. For task->comm exceeding
216 	 * size, guarantee that buf is %NUL-terminated. Unconditionally
217 	 * done here to save the size test.
218 	 */
219 	buf[size - 1] = 0;
220 	return 0;
221 err_clear:
222 	memset(buf, 0, size);
223 	return -EINVAL;
224 }
225 
226 const struct bpf_func_proto bpf_get_current_comm_proto = {
227 	.func		= bpf_get_current_comm,
228 	.gpl_only	= false,
229 	.ret_type	= RET_INTEGER,
230 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
231 	.arg2_type	= ARG_CONST_SIZE,
232 };
233 
234 #if defined(CONFIG_QUEUED_SPINLOCKS) || defined(CONFIG_BPF_ARCH_SPINLOCK)
235 
__bpf_spin_lock(struct bpf_spin_lock * lock)236 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
237 {
238 	arch_spinlock_t *l = (void *)lock;
239 	union {
240 		__u32 val;
241 		arch_spinlock_t lock;
242 	} u = { .lock = __ARCH_SPIN_LOCK_UNLOCKED };
243 
244 	compiletime_assert(u.val == 0, "__ARCH_SPIN_LOCK_UNLOCKED not 0");
245 	BUILD_BUG_ON(sizeof(*l) != sizeof(__u32));
246 	BUILD_BUG_ON(sizeof(*lock) != sizeof(__u32));
247 	arch_spin_lock(l);
248 }
249 
__bpf_spin_unlock(struct bpf_spin_lock * lock)250 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
251 {
252 	arch_spinlock_t *l = (void *)lock;
253 
254 	arch_spin_unlock(l);
255 }
256 
257 #else
258 
__bpf_spin_lock(struct bpf_spin_lock * lock)259 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
260 {
261 	atomic_t *l = (void *)lock;
262 
263 	BUILD_BUG_ON(sizeof(*l) != sizeof(*lock));
264 	do {
265 		atomic_cond_read_relaxed(l, !VAL);
266 	} while (atomic_xchg(l, 1));
267 }
268 
__bpf_spin_unlock(struct bpf_spin_lock * lock)269 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
270 {
271 	atomic_t *l = (void *)lock;
272 
273 	atomic_set_release(l, 0);
274 }
275 
276 #endif
277 
278 static DEFINE_PER_CPU(unsigned long, irqsave_flags);
279 
BPF_CALL_1(bpf_spin_lock,struct bpf_spin_lock *,lock)280 notrace BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
281 {
282 	unsigned long flags;
283 
284 	local_irq_save(flags);
285 	__bpf_spin_lock(lock);
286 	__this_cpu_write(irqsave_flags, flags);
287 	return 0;
288 }
289 
290 const struct bpf_func_proto bpf_spin_lock_proto = {
291 	.func		= bpf_spin_lock,
292 	.gpl_only	= false,
293 	.ret_type	= RET_VOID,
294 	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
295 };
296 
BPF_CALL_1(bpf_spin_unlock,struct bpf_spin_lock *,lock)297 notrace BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
298 {
299 	unsigned long flags;
300 
301 	flags = __this_cpu_read(irqsave_flags);
302 	__bpf_spin_unlock(lock);
303 	local_irq_restore(flags);
304 	return 0;
305 }
306 
307 const struct bpf_func_proto bpf_spin_unlock_proto = {
308 	.func		= bpf_spin_unlock,
309 	.gpl_only	= false,
310 	.ret_type	= RET_VOID,
311 	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
312 };
313 
copy_map_value_locked(struct bpf_map * map,void * dst,void * src,bool lock_src)314 void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
315 			   bool lock_src)
316 {
317 	struct bpf_spin_lock *lock;
318 
319 	if (lock_src)
320 		lock = src + map->spin_lock_off;
321 	else
322 		lock = dst + map->spin_lock_off;
323 	preempt_disable();
324 	____bpf_spin_lock(lock);
325 	copy_map_value(map, dst, src);
326 	____bpf_spin_unlock(lock);
327 	preempt_enable();
328 }
329 
BPF_CALL_0(bpf_jiffies64)330 BPF_CALL_0(bpf_jiffies64)
331 {
332 	return get_jiffies_64();
333 }
334 
335 const struct bpf_func_proto bpf_jiffies64_proto = {
336 	.func		= bpf_jiffies64,
337 	.gpl_only	= false,
338 	.ret_type	= RET_INTEGER,
339 };
340 
341 #ifdef CONFIG_CGROUPS
BPF_CALL_0(bpf_get_current_cgroup_id)342 BPF_CALL_0(bpf_get_current_cgroup_id)
343 {
344 	struct cgroup *cgrp = task_dfl_cgroup(current);
345 
346 	return cgroup_id(cgrp);
347 }
348 
349 const struct bpf_func_proto bpf_get_current_cgroup_id_proto = {
350 	.func		= bpf_get_current_cgroup_id,
351 	.gpl_only	= false,
352 	.ret_type	= RET_INTEGER,
353 };
354 
BPF_CALL_1(bpf_get_current_ancestor_cgroup_id,int,ancestor_level)355 BPF_CALL_1(bpf_get_current_ancestor_cgroup_id, int, ancestor_level)
356 {
357 	struct cgroup *cgrp = task_dfl_cgroup(current);
358 	struct cgroup *ancestor;
359 
360 	ancestor = cgroup_ancestor(cgrp, ancestor_level);
361 	if (!ancestor)
362 		return 0;
363 	return cgroup_id(ancestor);
364 }
365 
366 const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto = {
367 	.func		= bpf_get_current_ancestor_cgroup_id,
368 	.gpl_only	= false,
369 	.ret_type	= RET_INTEGER,
370 	.arg1_type	= ARG_ANYTHING,
371 };
372 
373 #ifdef CONFIG_CGROUP_BPF
374 DECLARE_PER_CPU(struct bpf_cgroup_storage*,
375 		bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
376 
BPF_CALL_2(bpf_get_local_storage,struct bpf_map *,map,u64,flags)377 BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
378 {
379 	/* flags argument is not used now,
380 	 * but provides an ability to extend the API.
381 	 * verifier checks that its value is correct.
382 	 */
383 	enum bpf_cgroup_storage_type stype = cgroup_storage_type(map);
384 	struct bpf_cgroup_storage *storage;
385 	void *ptr;
386 
387 	storage = this_cpu_read(bpf_cgroup_storage[stype]);
388 
389 	if (stype == BPF_CGROUP_STORAGE_SHARED)
390 		ptr = &READ_ONCE(storage->buf)->data[0];
391 	else
392 		ptr = this_cpu_ptr(storage->percpu_buf);
393 
394 	return (unsigned long)ptr;
395 }
396 
397 const struct bpf_func_proto bpf_get_local_storage_proto = {
398 	.func		= bpf_get_local_storage,
399 	.gpl_only	= false,
400 	.ret_type	= RET_PTR_TO_MAP_VALUE,
401 	.arg1_type	= ARG_CONST_MAP_PTR,
402 	.arg2_type	= ARG_ANYTHING,
403 };
404 #endif
405 
406 #define BPF_STRTOX_BASE_MASK 0x1F
407 
__bpf_strtoull(const char * buf,size_t buf_len,u64 flags,unsigned long long * res,bool * is_negative)408 static int __bpf_strtoull(const char *buf, size_t buf_len, u64 flags,
409 			  unsigned long long *res, bool *is_negative)
410 {
411 	unsigned int base = flags & BPF_STRTOX_BASE_MASK;
412 	const char *cur_buf = buf;
413 	size_t cur_len = buf_len;
414 	unsigned int consumed;
415 	size_t val_len;
416 	char str[64];
417 
418 	if (!buf || !buf_len || !res || !is_negative)
419 		return -EINVAL;
420 
421 	if (base != 0 && base != 8 && base != 10 && base != 16)
422 		return -EINVAL;
423 
424 	if (flags & ~BPF_STRTOX_BASE_MASK)
425 		return -EINVAL;
426 
427 	while (cur_buf < buf + buf_len && isspace(*cur_buf))
428 		++cur_buf;
429 
430 	*is_negative = (cur_buf < buf + buf_len && *cur_buf == '-');
431 	if (*is_negative)
432 		++cur_buf;
433 
434 	consumed = cur_buf - buf;
435 	cur_len -= consumed;
436 	if (!cur_len)
437 		return -EINVAL;
438 
439 	cur_len = min(cur_len, sizeof(str) - 1);
440 	memcpy(str, cur_buf, cur_len);
441 	str[cur_len] = '\0';
442 	cur_buf = str;
443 
444 	cur_buf = _parse_integer_fixup_radix(cur_buf, &base);
445 	val_len = _parse_integer(cur_buf, base, res);
446 
447 	if (val_len & KSTRTOX_OVERFLOW)
448 		return -ERANGE;
449 
450 	if (val_len == 0)
451 		return -EINVAL;
452 
453 	cur_buf += val_len;
454 	consumed += cur_buf - str;
455 
456 	return consumed;
457 }
458 
__bpf_strtoll(const char * buf,size_t buf_len,u64 flags,long long * res)459 static int __bpf_strtoll(const char *buf, size_t buf_len, u64 flags,
460 			 long long *res)
461 {
462 	unsigned long long _res;
463 	bool is_negative;
464 	int err;
465 
466 	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
467 	if (err < 0)
468 		return err;
469 	if (is_negative) {
470 		if ((long long)-_res > 0)
471 			return -ERANGE;
472 		*res = -_res;
473 	} else {
474 		if ((long long)_res < 0)
475 			return -ERANGE;
476 		*res = _res;
477 	}
478 	return err;
479 }
480 
BPF_CALL_4(bpf_strtol,const char *,buf,size_t,buf_len,u64,flags,long *,res)481 BPF_CALL_4(bpf_strtol, const char *, buf, size_t, buf_len, u64, flags,
482 	   long *, res)
483 {
484 	long long _res;
485 	int err;
486 
487 	err = __bpf_strtoll(buf, buf_len, flags, &_res);
488 	if (err < 0)
489 		return err;
490 	if (_res != (long)_res)
491 		return -ERANGE;
492 	*res = _res;
493 	return err;
494 }
495 
496 const struct bpf_func_proto bpf_strtol_proto = {
497 	.func		= bpf_strtol,
498 	.gpl_only	= false,
499 	.ret_type	= RET_INTEGER,
500 	.arg1_type	= ARG_PTR_TO_MEM,
501 	.arg2_type	= ARG_CONST_SIZE,
502 	.arg3_type	= ARG_ANYTHING,
503 	.arg4_type	= ARG_PTR_TO_LONG,
504 };
505 
BPF_CALL_4(bpf_strtoul,const char *,buf,size_t,buf_len,u64,flags,unsigned long *,res)506 BPF_CALL_4(bpf_strtoul, const char *, buf, size_t, buf_len, u64, flags,
507 	   unsigned long *, res)
508 {
509 	unsigned long long _res;
510 	bool is_negative;
511 	int err;
512 
513 	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
514 	if (err < 0)
515 		return err;
516 	if (is_negative)
517 		return -EINVAL;
518 	if (_res != (unsigned long)_res)
519 		return -ERANGE;
520 	*res = _res;
521 	return err;
522 }
523 
524 const struct bpf_func_proto bpf_strtoul_proto = {
525 	.func		= bpf_strtoul,
526 	.gpl_only	= false,
527 	.ret_type	= RET_INTEGER,
528 	.arg1_type	= ARG_PTR_TO_MEM,
529 	.arg2_type	= ARG_CONST_SIZE,
530 	.arg3_type	= ARG_ANYTHING,
531 	.arg4_type	= ARG_PTR_TO_LONG,
532 };
533 #endif
534 
BPF_CALL_4(bpf_get_ns_current_pid_tgid,u64,dev,u64,ino,struct bpf_pidns_info *,nsdata,u32,size)535 BPF_CALL_4(bpf_get_ns_current_pid_tgid, u64, dev, u64, ino,
536 	   struct bpf_pidns_info *, nsdata, u32, size)
537 {
538 	struct task_struct *task = current;
539 	struct pid_namespace *pidns;
540 	int err = -EINVAL;
541 
542 	if (unlikely(size != sizeof(struct bpf_pidns_info)))
543 		goto clear;
544 
545 	if (unlikely((u64)(dev_t)dev != dev))
546 		goto clear;
547 
548 	if (unlikely(!task))
549 		goto clear;
550 
551 	pidns = task_active_pid_ns(task);
552 	if (unlikely(!pidns)) {
553 		err = -ENOENT;
554 		goto clear;
555 	}
556 
557 	if (!ns_match(&pidns->ns, (dev_t)dev, ino))
558 		goto clear;
559 
560 	nsdata->pid = task_pid_nr_ns(task, pidns);
561 	nsdata->tgid = task_tgid_nr_ns(task, pidns);
562 	return 0;
563 clear:
564 	memset((void *)nsdata, 0, (size_t) size);
565 	return err;
566 }
567 
568 const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto = {
569 	.func		= bpf_get_ns_current_pid_tgid,
570 	.gpl_only	= false,
571 	.ret_type	= RET_INTEGER,
572 	.arg1_type	= ARG_ANYTHING,
573 	.arg2_type	= ARG_ANYTHING,
574 	.arg3_type      = ARG_PTR_TO_UNINIT_MEM,
575 	.arg4_type      = ARG_CONST_SIZE,
576 };
577 
578 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
579 	.func		= bpf_get_raw_cpu_id,
580 	.gpl_only	= false,
581 	.ret_type	= RET_INTEGER,
582 };
583 
BPF_CALL_5(bpf_event_output_data,void *,ctx,struct bpf_map *,map,u64,flags,void *,data,u64,size)584 BPF_CALL_5(bpf_event_output_data, void *, ctx, struct bpf_map *, map,
585 	   u64, flags, void *, data, u64, size)
586 {
587 	if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
588 		return -EINVAL;
589 
590 	return bpf_event_output(map, flags, data, size, NULL, 0, NULL);
591 }
592 
593 const struct bpf_func_proto bpf_event_output_data_proto =  {
594 	.func		= bpf_event_output_data,
595 	.gpl_only       = true,
596 	.ret_type       = RET_INTEGER,
597 	.arg1_type      = ARG_PTR_TO_CTX,
598 	.arg2_type      = ARG_CONST_MAP_PTR,
599 	.arg3_type      = ARG_ANYTHING,
600 	.arg4_type      = ARG_PTR_TO_MEM,
601 	.arg5_type      = ARG_CONST_SIZE_OR_ZERO,
602 };
603 
BPF_CALL_3(bpf_copy_from_user,void *,dst,u32,size,const void __user *,user_ptr)604 BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size,
605 	   const void __user *, user_ptr)
606 {
607 	int ret = copy_from_user(dst, user_ptr, size);
608 
609 	if (unlikely(ret)) {
610 		memset(dst, 0, size);
611 		ret = -EFAULT;
612 	}
613 
614 	return ret;
615 }
616 
617 const struct bpf_func_proto bpf_copy_from_user_proto = {
618 	.func		= bpf_copy_from_user,
619 	.gpl_only	= false,
620 	.ret_type	= RET_INTEGER,
621 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
622 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
623 	.arg3_type	= ARG_ANYTHING,
624 };
625 
BPF_CALL_2(bpf_per_cpu_ptr,const void *,ptr,u32,cpu)626 BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu)
627 {
628 	if (cpu >= nr_cpu_ids)
629 		return (unsigned long)NULL;
630 
631 	return (unsigned long)per_cpu_ptr((const void __percpu *)ptr, cpu);
632 }
633 
634 const struct bpf_func_proto bpf_per_cpu_ptr_proto = {
635 	.func		= bpf_per_cpu_ptr,
636 	.gpl_only	= false,
637 	.ret_type	= RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL,
638 	.arg1_type	= ARG_PTR_TO_PERCPU_BTF_ID,
639 	.arg2_type	= ARG_ANYTHING,
640 };
641 
BPF_CALL_1(bpf_this_cpu_ptr,const void *,percpu_ptr)642 BPF_CALL_1(bpf_this_cpu_ptr, const void *, percpu_ptr)
643 {
644 	return (unsigned long)this_cpu_ptr((const void __percpu *)percpu_ptr);
645 }
646 
647 const struct bpf_func_proto bpf_this_cpu_ptr_proto = {
648 	.func		= bpf_this_cpu_ptr,
649 	.gpl_only	= false,
650 	.ret_type	= RET_PTR_TO_MEM_OR_BTF_ID,
651 	.arg1_type	= ARG_PTR_TO_PERCPU_BTF_ID,
652 };
653 
654 const struct bpf_func_proto bpf_get_current_task_proto __weak;
655 const struct bpf_func_proto bpf_probe_read_user_proto __weak;
656 const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
657 const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
658 const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
659 
660 const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)661 bpf_base_func_proto(enum bpf_func_id func_id)
662 {
663 	switch (func_id) {
664 	case BPF_FUNC_map_lookup_elem:
665 		return &bpf_map_lookup_elem_proto;
666 	case BPF_FUNC_map_update_elem:
667 		return &bpf_map_update_elem_proto;
668 	case BPF_FUNC_map_delete_elem:
669 		return &bpf_map_delete_elem_proto;
670 	case BPF_FUNC_map_push_elem:
671 		return &bpf_map_push_elem_proto;
672 	case BPF_FUNC_map_pop_elem:
673 		return &bpf_map_pop_elem_proto;
674 	case BPF_FUNC_map_peek_elem:
675 		return &bpf_map_peek_elem_proto;
676 	case BPF_FUNC_get_prandom_u32:
677 		return &bpf_get_prandom_u32_proto;
678 	case BPF_FUNC_get_smp_processor_id:
679 		return &bpf_get_raw_smp_processor_id_proto;
680 	case BPF_FUNC_get_numa_node_id:
681 		return &bpf_get_numa_node_id_proto;
682 	case BPF_FUNC_tail_call:
683 		return &bpf_tail_call_proto;
684 	case BPF_FUNC_ktime_get_ns:
685 		return &bpf_ktime_get_ns_proto;
686 	case BPF_FUNC_ktime_get_boot_ns:
687 		return &bpf_ktime_get_boot_ns_proto;
688 	case BPF_FUNC_ringbuf_output:
689 		return &bpf_ringbuf_output_proto;
690 	case BPF_FUNC_ringbuf_reserve:
691 		return &bpf_ringbuf_reserve_proto;
692 	case BPF_FUNC_ringbuf_submit:
693 		return &bpf_ringbuf_submit_proto;
694 	case BPF_FUNC_ringbuf_discard:
695 		return &bpf_ringbuf_discard_proto;
696 	case BPF_FUNC_ringbuf_query:
697 		return &bpf_ringbuf_query_proto;
698 	default:
699 		break;
700 	}
701 
702 	if (!bpf_capable())
703 		return NULL;
704 
705 	switch (func_id) {
706 	case BPF_FUNC_spin_lock:
707 		return &bpf_spin_lock_proto;
708 	case BPF_FUNC_spin_unlock:
709 		return &bpf_spin_unlock_proto;
710 	case BPF_FUNC_trace_printk:
711 		if (!perfmon_capable())
712 			return NULL;
713 		return bpf_get_trace_printk_proto();
714 	case BPF_FUNC_snprintf_btf:
715 		if (!perfmon_capable())
716 			return NULL;
717 		return &bpf_snprintf_btf_proto;
718 	case BPF_FUNC_jiffies64:
719 		return &bpf_jiffies64_proto;
720 	case BPF_FUNC_per_cpu_ptr:
721 		return &bpf_per_cpu_ptr_proto;
722 	case BPF_FUNC_this_cpu_ptr:
723 		return &bpf_this_cpu_ptr_proto;
724 	default:
725 		break;
726 	}
727 
728 	if (!perfmon_capable())
729 		return NULL;
730 
731 	switch (func_id) {
732 	case BPF_FUNC_get_current_task:
733 		return &bpf_get_current_task_proto;
734 	case BPF_FUNC_probe_read_user:
735 		return &bpf_probe_read_user_proto;
736 	case BPF_FUNC_probe_read_kernel:
737 		return &bpf_probe_read_kernel_proto;
738 	case BPF_FUNC_probe_read_user_str:
739 		return &bpf_probe_read_user_str_proto;
740 	case BPF_FUNC_probe_read_kernel_str:
741 		return &bpf_probe_read_kernel_str_proto;
742 	default:
743 		return NULL;
744 	}
745 }
746