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v5.4
  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
 15#include "../../lib/kstrtox.h"
 16
 17/* If kernel subsystem is allowing eBPF programs to call this function,
 18 * inside its own verifier_ops->get_func_proto() callback it should return
 19 * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments
 20 *
 21 * Different map implementations will rely on rcu in map methods
 22 * lookup/update/delete, therefore eBPF programs must run under rcu lock
 23 * if program is allowed to access maps, so check rcu_read_lock_held in
 24 * all three functions.
 25 */
 26BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key)
 27{
 28	WARN_ON_ONCE(!rcu_read_lock_held());
 29	return (unsigned long) map->ops->map_lookup_elem(map, key);
 30}
 31
 32const struct bpf_func_proto bpf_map_lookup_elem_proto = {
 33	.func		= bpf_map_lookup_elem,
 34	.gpl_only	= false,
 35	.pkt_access	= true,
 36	.ret_type	= RET_PTR_TO_MAP_VALUE_OR_NULL,
 37	.arg1_type	= ARG_CONST_MAP_PTR,
 38	.arg2_type	= ARG_PTR_TO_MAP_KEY,
 39};
 40
 41BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key,
 42	   void *, value, u64, flags)
 43{
 44	WARN_ON_ONCE(!rcu_read_lock_held());
 45	return map->ops->map_update_elem(map, key, value, flags);
 46}
 47
 48const struct bpf_func_proto bpf_map_update_elem_proto = {
 49	.func		= bpf_map_update_elem,
 50	.gpl_only	= false,
 51	.pkt_access	= true,
 52	.ret_type	= RET_INTEGER,
 53	.arg1_type	= ARG_CONST_MAP_PTR,
 54	.arg2_type	= ARG_PTR_TO_MAP_KEY,
 55	.arg3_type	= ARG_PTR_TO_MAP_VALUE,
 56	.arg4_type	= ARG_ANYTHING,
 57};
 58
 59BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key)
 60{
 61	WARN_ON_ONCE(!rcu_read_lock_held());
 62	return map->ops->map_delete_elem(map, key);
 63}
 64
 65const struct bpf_func_proto bpf_map_delete_elem_proto = {
 66	.func		= bpf_map_delete_elem,
 67	.gpl_only	= false,
 68	.pkt_access	= true,
 69	.ret_type	= RET_INTEGER,
 70	.arg1_type	= ARG_CONST_MAP_PTR,
 71	.arg2_type	= ARG_PTR_TO_MAP_KEY,
 72};
 73
 74BPF_CALL_3(bpf_map_push_elem, struct bpf_map *, map, void *, value, u64, flags)
 75{
 76	return map->ops->map_push_elem(map, value, flags);
 77}
 78
 79const struct bpf_func_proto bpf_map_push_elem_proto = {
 80	.func		= bpf_map_push_elem,
 81	.gpl_only	= false,
 82	.pkt_access	= true,
 83	.ret_type	= RET_INTEGER,
 84	.arg1_type	= ARG_CONST_MAP_PTR,
 85	.arg2_type	= ARG_PTR_TO_MAP_VALUE,
 86	.arg3_type	= ARG_ANYTHING,
 87};
 88
 89BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value)
 90{
 91	return map->ops->map_pop_elem(map, value);
 92}
 93
 94const struct bpf_func_proto bpf_map_pop_elem_proto = {
 95	.func		= bpf_map_pop_elem,
 96	.gpl_only	= false,
 97	.ret_type	= RET_INTEGER,
 98	.arg1_type	= ARG_CONST_MAP_PTR,
 99	.arg2_type	= ARG_PTR_TO_UNINIT_MAP_VALUE,
100};
101
102BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value)
103{
104	return map->ops->map_peek_elem(map, value);
105}
106
107const struct bpf_func_proto bpf_map_peek_elem_proto = {
108	.func		= bpf_map_pop_elem,
109	.gpl_only	= false,
110	.ret_type	= RET_INTEGER,
111	.arg1_type	= ARG_CONST_MAP_PTR,
112	.arg2_type	= ARG_PTR_TO_UNINIT_MAP_VALUE,
113};
114
115const struct bpf_func_proto bpf_get_prandom_u32_proto = {
116	.func		= bpf_user_rnd_u32,
117	.gpl_only	= false,
118	.ret_type	= RET_INTEGER,
119};
120
121BPF_CALL_0(bpf_get_smp_processor_id)
122{
123	return smp_processor_id();
124}
125
126const struct bpf_func_proto bpf_get_smp_processor_id_proto = {
127	.func		= bpf_get_smp_processor_id,
128	.gpl_only	= false,
129	.ret_type	= RET_INTEGER,
130};
131
132BPF_CALL_0(bpf_get_numa_node_id)
133{
134	return numa_node_id();
135}
136
137const struct bpf_func_proto bpf_get_numa_node_id_proto = {
138	.func		= bpf_get_numa_node_id,
139	.gpl_only	= false,
140	.ret_type	= RET_INTEGER,
141};
142
143BPF_CALL_0(bpf_ktime_get_ns)
144{
145	/* NMI safe access to clock monotonic */
146	return ktime_get_mono_fast_ns();
147}
148
149const struct bpf_func_proto bpf_ktime_get_ns_proto = {
150	.func		= bpf_ktime_get_ns,
151	.gpl_only	= true,
 
 
 
 
 
 
 
 
 
 
 
 
152	.ret_type	= RET_INTEGER,
153};
154
155BPF_CALL_0(bpf_get_current_pid_tgid)
156{
157	struct task_struct *task = current;
158
159	if (unlikely(!task))
160		return -EINVAL;
161
162	return (u64) task->tgid << 32 | task->pid;
163}
164
165const struct bpf_func_proto bpf_get_current_pid_tgid_proto = {
166	.func		= bpf_get_current_pid_tgid,
167	.gpl_only	= false,
168	.ret_type	= RET_INTEGER,
169};
170
171BPF_CALL_0(bpf_get_current_uid_gid)
172{
173	struct task_struct *task = current;
174	kuid_t uid;
175	kgid_t gid;
176
177	if (unlikely(!task))
178		return -EINVAL;
179
180	current_uid_gid(&uid, &gid);
181	return (u64) from_kgid(&init_user_ns, gid) << 32 |
182		     from_kuid(&init_user_ns, uid);
183}
184
185const struct bpf_func_proto bpf_get_current_uid_gid_proto = {
186	.func		= bpf_get_current_uid_gid,
187	.gpl_only	= false,
188	.ret_type	= RET_INTEGER,
189};
190
191BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
192{
193	struct task_struct *task = current;
194
195	if (unlikely(!task))
196		goto err_clear;
197
198	strncpy(buf, task->comm, size);
199
200	/* Verifier guarantees that size > 0. For task->comm exceeding
201	 * size, guarantee that buf is %NUL-terminated. Unconditionally
202	 * done here to save the size test.
203	 */
204	buf[size - 1] = 0;
205	return 0;
206err_clear:
207	memset(buf, 0, size);
208	return -EINVAL;
209}
210
211const struct bpf_func_proto bpf_get_current_comm_proto = {
212	.func		= bpf_get_current_comm,
213	.gpl_only	= false,
214	.ret_type	= RET_INTEGER,
215	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
216	.arg2_type	= ARG_CONST_SIZE,
217};
218
219#if defined(CONFIG_QUEUED_SPINLOCKS) || defined(CONFIG_BPF_ARCH_SPINLOCK)
220
221static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
222{
223	arch_spinlock_t *l = (void *)lock;
224	union {
225		__u32 val;
226		arch_spinlock_t lock;
227	} u = { .lock = __ARCH_SPIN_LOCK_UNLOCKED };
228
229	compiletime_assert(u.val == 0, "__ARCH_SPIN_LOCK_UNLOCKED not 0");
230	BUILD_BUG_ON(sizeof(*l) != sizeof(__u32));
231	BUILD_BUG_ON(sizeof(*lock) != sizeof(__u32));
232	arch_spin_lock(l);
233}
234
235static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
236{
237	arch_spinlock_t *l = (void *)lock;
238
239	arch_spin_unlock(l);
240}
241
242#else
243
244static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
245{
246	atomic_t *l = (void *)lock;
247
248	BUILD_BUG_ON(sizeof(*l) != sizeof(*lock));
249	do {
250		atomic_cond_read_relaxed(l, !VAL);
251	} while (atomic_xchg(l, 1));
252}
253
254static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
255{
256	atomic_t *l = (void *)lock;
257
258	atomic_set_release(l, 0);
259}
260
261#endif
262
263static DEFINE_PER_CPU(unsigned long, irqsave_flags);
264
265notrace BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
266{
267	unsigned long flags;
268
269	local_irq_save(flags);
270	__bpf_spin_lock(lock);
271	__this_cpu_write(irqsave_flags, flags);
272	return 0;
273}
274
275const struct bpf_func_proto bpf_spin_lock_proto = {
276	.func		= bpf_spin_lock,
277	.gpl_only	= false,
278	.ret_type	= RET_VOID,
279	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
280};
281
282notrace BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
283{
284	unsigned long flags;
285
286	flags = __this_cpu_read(irqsave_flags);
287	__bpf_spin_unlock(lock);
288	local_irq_restore(flags);
289	return 0;
290}
291
292const struct bpf_func_proto bpf_spin_unlock_proto = {
293	.func		= bpf_spin_unlock,
294	.gpl_only	= false,
295	.ret_type	= RET_VOID,
296	.arg1_type	= ARG_PTR_TO_SPIN_LOCK,
297};
298
299void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
300			   bool lock_src)
301{
302	struct bpf_spin_lock *lock;
303
304	if (lock_src)
305		lock = src + map->spin_lock_off;
306	else
307		lock = dst + map->spin_lock_off;
308	preempt_disable();
309	____bpf_spin_lock(lock);
310	copy_map_value(map, dst, src);
311	____bpf_spin_unlock(lock);
312	preempt_enable();
313}
314
 
 
 
 
 
 
 
 
 
 
 
315#ifdef CONFIG_CGROUPS
316BPF_CALL_0(bpf_get_current_cgroup_id)
317{
318	struct cgroup *cgrp = task_dfl_cgroup(current);
319
320	return cgrp->kn->id.id;
321}
322
323const struct bpf_func_proto bpf_get_current_cgroup_id_proto = {
324	.func		= bpf_get_current_cgroup_id,
325	.gpl_only	= false,
326	.ret_type	= RET_INTEGER,
327};
328
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
329#ifdef CONFIG_CGROUP_BPF
330DECLARE_PER_CPU(struct bpf_cgroup_storage*,
331		bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
332
333BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
334{
335	/* flags argument is not used now,
336	 * but provides an ability to extend the API.
337	 * verifier checks that its value is correct.
338	 */
339	enum bpf_cgroup_storage_type stype = cgroup_storage_type(map);
340	struct bpf_cgroup_storage *storage;
341	void *ptr;
342
343	storage = this_cpu_read(bpf_cgroup_storage[stype]);
344
345	if (stype == BPF_CGROUP_STORAGE_SHARED)
346		ptr = &READ_ONCE(storage->buf)->data[0];
347	else
348		ptr = this_cpu_ptr(storage->percpu_buf);
349
350	return (unsigned long)ptr;
351}
352
353const struct bpf_func_proto bpf_get_local_storage_proto = {
354	.func		= bpf_get_local_storage,
355	.gpl_only	= false,
356	.ret_type	= RET_PTR_TO_MAP_VALUE,
357	.arg1_type	= ARG_CONST_MAP_PTR,
358	.arg2_type	= ARG_ANYTHING,
359};
360#endif
361
362#define BPF_STRTOX_BASE_MASK 0x1F
363
364static int __bpf_strtoull(const char *buf, size_t buf_len, u64 flags,
365			  unsigned long long *res, bool *is_negative)
366{
367	unsigned int base = flags & BPF_STRTOX_BASE_MASK;
368	const char *cur_buf = buf;
369	size_t cur_len = buf_len;
370	unsigned int consumed;
371	size_t val_len;
372	char str[64];
373
374	if (!buf || !buf_len || !res || !is_negative)
375		return -EINVAL;
376
377	if (base != 0 && base != 8 && base != 10 && base != 16)
378		return -EINVAL;
379
380	if (flags & ~BPF_STRTOX_BASE_MASK)
381		return -EINVAL;
382
383	while (cur_buf < buf + buf_len && isspace(*cur_buf))
384		++cur_buf;
385
386	*is_negative = (cur_buf < buf + buf_len && *cur_buf == '-');
387	if (*is_negative)
388		++cur_buf;
389
390	consumed = cur_buf - buf;
391	cur_len -= consumed;
392	if (!cur_len)
393		return -EINVAL;
394
395	cur_len = min(cur_len, sizeof(str) - 1);
396	memcpy(str, cur_buf, cur_len);
397	str[cur_len] = '\0';
398	cur_buf = str;
399
400	cur_buf = _parse_integer_fixup_radix(cur_buf, &base);
401	val_len = _parse_integer(cur_buf, base, res);
402
403	if (val_len & KSTRTOX_OVERFLOW)
404		return -ERANGE;
405
406	if (val_len == 0)
407		return -EINVAL;
408
409	cur_buf += val_len;
410	consumed += cur_buf - str;
411
412	return consumed;
413}
414
415static int __bpf_strtoll(const char *buf, size_t buf_len, u64 flags,
416			 long long *res)
417{
418	unsigned long long _res;
419	bool is_negative;
420	int err;
421
422	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
423	if (err < 0)
424		return err;
425	if (is_negative) {
426		if ((long long)-_res > 0)
427			return -ERANGE;
428		*res = -_res;
429	} else {
430		if ((long long)_res < 0)
431			return -ERANGE;
432		*res = _res;
433	}
434	return err;
435}
436
437BPF_CALL_4(bpf_strtol, const char *, buf, size_t, buf_len, u64, flags,
438	   long *, res)
439{
440	long long _res;
441	int err;
442
443	err = __bpf_strtoll(buf, buf_len, flags, &_res);
444	if (err < 0)
445		return err;
446	if (_res != (long)_res)
447		return -ERANGE;
448	*res = _res;
449	return err;
450}
451
452const struct bpf_func_proto bpf_strtol_proto = {
453	.func		= bpf_strtol,
454	.gpl_only	= false,
455	.ret_type	= RET_INTEGER,
456	.arg1_type	= ARG_PTR_TO_MEM,
457	.arg2_type	= ARG_CONST_SIZE,
458	.arg3_type	= ARG_ANYTHING,
459	.arg4_type	= ARG_PTR_TO_LONG,
460};
461
462BPF_CALL_4(bpf_strtoul, const char *, buf, size_t, buf_len, u64, flags,
463	   unsigned long *, res)
464{
465	unsigned long long _res;
466	bool is_negative;
467	int err;
468
469	err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
470	if (err < 0)
471		return err;
472	if (is_negative)
473		return -EINVAL;
474	if (_res != (unsigned long)_res)
475		return -ERANGE;
476	*res = _res;
477	return err;
478}
479
480const struct bpf_func_proto bpf_strtoul_proto = {
481	.func		= bpf_strtoul,
482	.gpl_only	= false,
483	.ret_type	= RET_INTEGER,
484	.arg1_type	= ARG_PTR_TO_MEM,
485	.arg2_type	= ARG_CONST_SIZE,
486	.arg3_type	= ARG_ANYTHING,
487	.arg4_type	= ARG_PTR_TO_LONG,
488};
489#endif
v5.9
  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 */
 29BPF_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
 35const 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
 44BPF_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
 51const 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
 62BPF_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
 68const 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
 77BPF_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
 82const 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
 92BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value)
 93{
 94	return map->ops->map_pop_elem(map, value);
 95}
 96
 97const 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
105BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value)
106{
107	return map->ops->map_peek_elem(map, value);
108}
109
110const 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
118const 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
124BPF_CALL_0(bpf_get_smp_processor_id)
125{
126	return smp_processor_id();
127}
128
129const 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
135BPF_CALL_0(bpf_get_numa_node_id)
136{
137	return numa_node_id();
138}
139
140const 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
146BPF_CALL_0(bpf_ktime_get_ns)
147{
148	/* NMI safe access to clock monotonic */
149	return ktime_get_mono_fast_ns();
150}
151
152const 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
158BPF_CALL_0(bpf_ktime_get_boot_ns)
159{
160	/* NMI safe access to clock boottime */
161	return ktime_get_boot_fast_ns();
162}
163
164const 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
170BPF_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
180const 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
186BPF_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
200const 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
206BPF_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;
221err_clear:
222	memset(buf, 0, size);
223	return -EINVAL;
224}
225
226const 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
236static 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
250static 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
259static 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
269static 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
278static DEFINE_PER_CPU(unsigned long, irqsave_flags);
279
280notrace 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
290const 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
297notrace 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
307const 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
314void 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
330BPF_CALL_0(bpf_jiffies64)
331{
332	return get_jiffies_64();
333}
334
335const 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
342BPF_CALL_0(bpf_get_current_cgroup_id)
343{
344	struct cgroup *cgrp = task_dfl_cgroup(current);
345
346	return cgroup_id(cgrp);
347}
348
349const 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
355BPF_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
366const 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
374DECLARE_PER_CPU(struct bpf_cgroup_storage*,
375		bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
376
377BPF_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
397const 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
408static 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
459static 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
481BPF_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
496const 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
506BPF_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
524const 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
535BPF_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;
563clear:
564	memset((void *)nsdata, 0, (size_t) size);
565	return err;
566}
567
568const 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
578static 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
584BPF_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
593const 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
604const struct bpf_func_proto bpf_get_current_task_proto __weak;
605const struct bpf_func_proto bpf_probe_read_user_proto __weak;
606const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
607const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
608const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
609
610const struct bpf_func_proto *
611bpf_base_func_proto(enum bpf_func_id func_id)
612{
613	switch (func_id) {
614	case BPF_FUNC_map_lookup_elem:
615		return &bpf_map_lookup_elem_proto;
616	case BPF_FUNC_map_update_elem:
617		return &bpf_map_update_elem_proto;
618	case BPF_FUNC_map_delete_elem:
619		return &bpf_map_delete_elem_proto;
620	case BPF_FUNC_map_push_elem:
621		return &bpf_map_push_elem_proto;
622	case BPF_FUNC_map_pop_elem:
623		return &bpf_map_pop_elem_proto;
624	case BPF_FUNC_map_peek_elem:
625		return &bpf_map_peek_elem_proto;
626	case BPF_FUNC_get_prandom_u32:
627		return &bpf_get_prandom_u32_proto;
628	case BPF_FUNC_get_smp_processor_id:
629		return &bpf_get_raw_smp_processor_id_proto;
630	case BPF_FUNC_get_numa_node_id:
631		return &bpf_get_numa_node_id_proto;
632	case BPF_FUNC_tail_call:
633		return &bpf_tail_call_proto;
634	case BPF_FUNC_ktime_get_ns:
635		return &bpf_ktime_get_ns_proto;
636	case BPF_FUNC_ktime_get_boot_ns:
637		return &bpf_ktime_get_boot_ns_proto;
638	case BPF_FUNC_ringbuf_output:
639		return &bpf_ringbuf_output_proto;
640	case BPF_FUNC_ringbuf_reserve:
641		return &bpf_ringbuf_reserve_proto;
642	case BPF_FUNC_ringbuf_submit:
643		return &bpf_ringbuf_submit_proto;
644	case BPF_FUNC_ringbuf_discard:
645		return &bpf_ringbuf_discard_proto;
646	case BPF_FUNC_ringbuf_query:
647		return &bpf_ringbuf_query_proto;
648	default:
649		break;
650	}
651
652	if (!bpf_capable())
653		return NULL;
654
655	switch (func_id) {
656	case BPF_FUNC_spin_lock:
657		return &bpf_spin_lock_proto;
658	case BPF_FUNC_spin_unlock:
659		return &bpf_spin_unlock_proto;
660	case BPF_FUNC_trace_printk:
661		if (!perfmon_capable())
662			return NULL;
663		return bpf_get_trace_printk_proto();
664	case BPF_FUNC_jiffies64:
665		return &bpf_jiffies64_proto;
666	default:
667		break;
668	}
669
670	if (!perfmon_capable())
671		return NULL;
672
673	switch (func_id) {
674	case BPF_FUNC_get_current_task:
675		return &bpf_get_current_task_proto;
676	case BPF_FUNC_probe_read_user:
677		return &bpf_probe_read_user_proto;
678	case BPF_FUNC_probe_read_kernel:
679		return &bpf_probe_read_kernel_proto;
680	case BPF_FUNC_probe_read_user_str:
681		return &bpf_probe_read_user_str_proto;
682	case BPF_FUNC_probe_read_kernel_str:
683		return &bpf_probe_read_kernel_str_proto;
684	default:
685		return NULL;
686	}
687}