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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 151
[mirror_ubuntu-jammy-kernel.git] / kernel / bpf / syscall.c
1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
2 *
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of version 2 of the GNU General Public
5 * License as published by the Free Software Foundation.
6 *
7 * This program is distributed in the hope that it will be useful, but
8 * WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * General Public License for more details.
11 */
12 #include <linux/bpf.h>
13 #include <linux/bpf_trace.h>
14 #include <linux/bpf_lirc.h>
15 #include <linux/btf.h>
16 #include <linux/syscalls.h>
17 #include <linux/slab.h>
18 #include <linux/sched/signal.h>
19 #include <linux/vmalloc.h>
20 #include <linux/mmzone.h>
21 #include <linux/anon_inodes.h>
22 #include <linux/fdtable.h>
23 #include <linux/file.h>
24 #include <linux/fs.h>
25 #include <linux/license.h>
26 #include <linux/filter.h>
27 #include <linux/version.h>
28 #include <linux/kernel.h>
29 #include <linux/idr.h>
30 #include <linux/cred.h>
31 #include <linux/timekeeping.h>
32 #include <linux/ctype.h>
33 #include <linux/nospec.h>
34
35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
36 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
37 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
38 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
39 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
41
42 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
43
44 DEFINE_PER_CPU(int, bpf_prog_active);
45 static DEFINE_IDR(prog_idr);
46 static DEFINE_SPINLOCK(prog_idr_lock);
47 static DEFINE_IDR(map_idr);
48 static DEFINE_SPINLOCK(map_idr_lock);
49
50 int sysctl_unprivileged_bpf_disabled __read_mostly;
51
52 static const struct bpf_map_ops * const bpf_map_types[] = {
53 #define BPF_PROG_TYPE(_id, _ops)
54 #define BPF_MAP_TYPE(_id, _ops) \
55 [_id] = &_ops,
56 #include <linux/bpf_types.h>
57 #undef BPF_PROG_TYPE
58 #undef BPF_MAP_TYPE
59 };
60
61 /*
62 * If we're handed a bigger struct than we know of, ensure all the unknown bits
63 * are 0 - i.e. new user-space does not rely on any kernel feature extensions
64 * we don't know about yet.
65 *
66 * There is a ToCToU between this function call and the following
67 * copy_from_user() call. However, this is not a concern since this function is
68 * meant to be a future-proofing of bits.
69 */
70 int bpf_check_uarg_tail_zero(void __user *uaddr,
71 size_t expected_size,
72 size_t actual_size)
73 {
74 unsigned char __user *addr;
75 unsigned char __user *end;
76 unsigned char val;
77 int err;
78
79 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
80 return -E2BIG;
81
82 if (unlikely(!access_ok(uaddr, actual_size)))
83 return -EFAULT;
84
85 if (actual_size <= expected_size)
86 return 0;
87
88 addr = uaddr + expected_size;
89 end = uaddr + actual_size;
90
91 for (; addr < end; addr++) {
92 err = get_user(val, addr);
93 if (err)
94 return err;
95 if (val)
96 return -E2BIG;
97 }
98
99 return 0;
100 }
101
102 const struct bpf_map_ops bpf_map_offload_ops = {
103 .map_alloc = bpf_map_offload_map_alloc,
104 .map_free = bpf_map_offload_map_free,
105 .map_check_btf = map_check_no_btf,
106 };
107
108 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
109 {
110 const struct bpf_map_ops *ops;
111 u32 type = attr->map_type;
112 struct bpf_map *map;
113 int err;
114
115 if (type >= ARRAY_SIZE(bpf_map_types))
116 return ERR_PTR(-EINVAL);
117 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
118 ops = bpf_map_types[type];
119 if (!ops)
120 return ERR_PTR(-EINVAL);
121
122 if (ops->map_alloc_check) {
123 err = ops->map_alloc_check(attr);
124 if (err)
125 return ERR_PTR(err);
126 }
127 if (attr->map_ifindex)
128 ops = &bpf_map_offload_ops;
129 map = ops->map_alloc(attr);
130 if (IS_ERR(map))
131 return map;
132 map->ops = ops;
133 map->map_type = type;
134 return map;
135 }
136
137 void *bpf_map_area_alloc(size_t size, int numa_node)
138 {
139 /* We really just want to fail instead of triggering OOM killer
140 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
141 * which is used for lower order allocation requests.
142 *
143 * It has been observed that higher order allocation requests done by
144 * vmalloc with __GFP_NORETRY being set might fail due to not trying
145 * to reclaim memory from the page cache, thus we set
146 * __GFP_RETRY_MAYFAIL to avoid such situations.
147 */
148
149 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
150 void *area;
151
152 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
153 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
154 numa_node);
155 if (area != NULL)
156 return area;
157 }
158
159 return __vmalloc_node_flags_caller(size, numa_node,
160 GFP_KERNEL | __GFP_RETRY_MAYFAIL |
161 flags, __builtin_return_address(0));
162 }
163
164 void bpf_map_area_free(void *area)
165 {
166 kvfree(area);
167 }
168
169 static u32 bpf_map_flags_retain_permanent(u32 flags)
170 {
171 /* Some map creation flags are not tied to the map object but
172 * rather to the map fd instead, so they have no meaning upon
173 * map object inspection since multiple file descriptors with
174 * different (access) properties can exist here. Thus, given
175 * this has zero meaning for the map itself, lets clear these
176 * from here.
177 */
178 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
179 }
180
181 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
182 {
183 map->map_type = attr->map_type;
184 map->key_size = attr->key_size;
185 map->value_size = attr->value_size;
186 map->max_entries = attr->max_entries;
187 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
188 map->numa_node = bpf_map_attr_numa_node(attr);
189 }
190
191 int bpf_map_precharge_memlock(u32 pages)
192 {
193 struct user_struct *user = get_current_user();
194 unsigned long memlock_limit, cur;
195
196 memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
197 cur = atomic_long_read(&user->locked_vm);
198 free_uid(user);
199 if (cur + pages > memlock_limit)
200 return -EPERM;
201 return 0;
202 }
203
204 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
205 {
206 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
207
208 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
209 atomic_long_sub(pages, &user->locked_vm);
210 return -EPERM;
211 }
212 return 0;
213 }
214
215 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
216 {
217 atomic_long_sub(pages, &user->locked_vm);
218 }
219
220 static int bpf_map_init_memlock(struct bpf_map *map)
221 {
222 struct user_struct *user = get_current_user();
223 int ret;
224
225 ret = bpf_charge_memlock(user, map->pages);
226 if (ret) {
227 free_uid(user);
228 return ret;
229 }
230 map->user = user;
231 return ret;
232 }
233
234 static void bpf_map_release_memlock(struct bpf_map *map)
235 {
236 struct user_struct *user = map->user;
237 bpf_uncharge_memlock(user, map->pages);
238 free_uid(user);
239 }
240
241 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
242 {
243 int ret;
244
245 ret = bpf_charge_memlock(map->user, pages);
246 if (ret)
247 return ret;
248 map->pages += pages;
249 return ret;
250 }
251
252 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
253 {
254 bpf_uncharge_memlock(map->user, pages);
255 map->pages -= pages;
256 }
257
258 static int bpf_map_alloc_id(struct bpf_map *map)
259 {
260 int id;
261
262 idr_preload(GFP_KERNEL);
263 spin_lock_bh(&map_idr_lock);
264 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
265 if (id > 0)
266 map->id = id;
267 spin_unlock_bh(&map_idr_lock);
268 idr_preload_end();
269
270 if (WARN_ON_ONCE(!id))
271 return -ENOSPC;
272
273 return id > 0 ? 0 : id;
274 }
275
276 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
277 {
278 unsigned long flags;
279
280 /* Offloaded maps are removed from the IDR store when their device
281 * disappears - even if someone holds an fd to them they are unusable,
282 * the memory is gone, all ops will fail; they are simply waiting for
283 * refcnt to drop to be freed.
284 */
285 if (!map->id)
286 return;
287
288 if (do_idr_lock)
289 spin_lock_irqsave(&map_idr_lock, flags);
290 else
291 __acquire(&map_idr_lock);
292
293 idr_remove(&map_idr, map->id);
294 map->id = 0;
295
296 if (do_idr_lock)
297 spin_unlock_irqrestore(&map_idr_lock, flags);
298 else
299 __release(&map_idr_lock);
300 }
301
302 /* called from workqueue */
303 static void bpf_map_free_deferred(struct work_struct *work)
304 {
305 struct bpf_map *map = container_of(work, struct bpf_map, work);
306
307 bpf_map_release_memlock(map);
308 security_bpf_map_free(map);
309 /* implementation dependent freeing */
310 map->ops->map_free(map);
311 }
312
313 static void bpf_map_put_uref(struct bpf_map *map)
314 {
315 if (atomic_dec_and_test(&map->usercnt)) {
316 if (map->ops->map_release_uref)
317 map->ops->map_release_uref(map);
318 }
319 }
320
321 /* decrement map refcnt and schedule it for freeing via workqueue
322 * (unrelying map implementation ops->map_free() might sleep)
323 */
324 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
325 {
326 if (atomic_dec_and_test(&map->refcnt)) {
327 /* bpf_map_free_id() must be called first */
328 bpf_map_free_id(map, do_idr_lock);
329 btf_put(map->btf);
330 INIT_WORK(&map->work, bpf_map_free_deferred);
331 schedule_work(&map->work);
332 }
333 }
334
335 void bpf_map_put(struct bpf_map *map)
336 {
337 __bpf_map_put(map, true);
338 }
339 EXPORT_SYMBOL_GPL(bpf_map_put);
340
341 void bpf_map_put_with_uref(struct bpf_map *map)
342 {
343 bpf_map_put_uref(map);
344 bpf_map_put(map);
345 }
346
347 static int bpf_map_release(struct inode *inode, struct file *filp)
348 {
349 struct bpf_map *map = filp->private_data;
350
351 if (map->ops->map_release)
352 map->ops->map_release(map, filp);
353
354 bpf_map_put_with_uref(map);
355 return 0;
356 }
357
358 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
359 {
360 fmode_t mode = f.file->f_mode;
361
362 /* Our file permissions may have been overridden by global
363 * map permissions facing syscall side.
364 */
365 if (READ_ONCE(map->frozen))
366 mode &= ~FMODE_CAN_WRITE;
367 return mode;
368 }
369
370 #ifdef CONFIG_PROC_FS
371 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
372 {
373 const struct bpf_map *map = filp->private_data;
374 const struct bpf_array *array;
375 u32 owner_prog_type = 0;
376 u32 owner_jited = 0;
377
378 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
379 array = container_of(map, struct bpf_array, map);
380 owner_prog_type = array->owner_prog_type;
381 owner_jited = array->owner_jited;
382 }
383
384 seq_printf(m,
385 "map_type:\t%u\n"
386 "key_size:\t%u\n"
387 "value_size:\t%u\n"
388 "max_entries:\t%u\n"
389 "map_flags:\t%#x\n"
390 "memlock:\t%llu\n"
391 "map_id:\t%u\n"
392 "frozen:\t%u\n",
393 map->map_type,
394 map->key_size,
395 map->value_size,
396 map->max_entries,
397 map->map_flags,
398 map->pages * 1ULL << PAGE_SHIFT,
399 map->id,
400 READ_ONCE(map->frozen));
401
402 if (owner_prog_type) {
403 seq_printf(m, "owner_prog_type:\t%u\n",
404 owner_prog_type);
405 seq_printf(m, "owner_jited:\t%u\n",
406 owner_jited);
407 }
408 }
409 #endif
410
411 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
412 loff_t *ppos)
413 {
414 /* We need this handler such that alloc_file() enables
415 * f_mode with FMODE_CAN_READ.
416 */
417 return -EINVAL;
418 }
419
420 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
421 size_t siz, loff_t *ppos)
422 {
423 /* We need this handler such that alloc_file() enables
424 * f_mode with FMODE_CAN_WRITE.
425 */
426 return -EINVAL;
427 }
428
429 const struct file_operations bpf_map_fops = {
430 #ifdef CONFIG_PROC_FS
431 .show_fdinfo = bpf_map_show_fdinfo,
432 #endif
433 .release = bpf_map_release,
434 .read = bpf_dummy_read,
435 .write = bpf_dummy_write,
436 };
437
438 int bpf_map_new_fd(struct bpf_map *map, int flags)
439 {
440 int ret;
441
442 ret = security_bpf_map(map, OPEN_FMODE(flags));
443 if (ret < 0)
444 return ret;
445
446 return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
447 flags | O_CLOEXEC);
448 }
449
450 int bpf_get_file_flag(int flags)
451 {
452 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
453 return -EINVAL;
454 if (flags & BPF_F_RDONLY)
455 return O_RDONLY;
456 if (flags & BPF_F_WRONLY)
457 return O_WRONLY;
458 return O_RDWR;
459 }
460
461 /* helper macro to check that unused fields 'union bpf_attr' are zero */
462 #define CHECK_ATTR(CMD) \
463 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
464 sizeof(attr->CMD##_LAST_FIELD), 0, \
465 sizeof(*attr) - \
466 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
467 sizeof(attr->CMD##_LAST_FIELD)) != NULL
468
469 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
470 * Return 0 on success and < 0 on error.
471 */
472 static int bpf_obj_name_cpy(char *dst, const char *src)
473 {
474 const char *end = src + BPF_OBJ_NAME_LEN;
475
476 memset(dst, 0, BPF_OBJ_NAME_LEN);
477 /* Copy all isalnum(), '_' and '.' chars. */
478 while (src < end && *src) {
479 if (!isalnum(*src) &&
480 *src != '_' && *src != '.')
481 return -EINVAL;
482 *dst++ = *src++;
483 }
484
485 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
486 if (src == end)
487 return -EINVAL;
488
489 return 0;
490 }
491
492 int map_check_no_btf(const struct bpf_map *map,
493 const struct btf *btf,
494 const struct btf_type *key_type,
495 const struct btf_type *value_type)
496 {
497 return -ENOTSUPP;
498 }
499
500 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
501 u32 btf_key_id, u32 btf_value_id)
502 {
503 const struct btf_type *key_type, *value_type;
504 u32 key_size, value_size;
505 int ret = 0;
506
507 /* Some maps allow key to be unspecified. */
508 if (btf_key_id) {
509 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
510 if (!key_type || key_size != map->key_size)
511 return -EINVAL;
512 } else {
513 key_type = btf_type_by_id(btf, 0);
514 if (!map->ops->map_check_btf)
515 return -EINVAL;
516 }
517
518 value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
519 if (!value_type || value_size != map->value_size)
520 return -EINVAL;
521
522 map->spin_lock_off = btf_find_spin_lock(btf, value_type);
523
524 if (map_value_has_spin_lock(map)) {
525 if (map->map_flags & BPF_F_RDONLY_PROG)
526 return -EACCES;
527 if (map->map_type != BPF_MAP_TYPE_HASH &&
528 map->map_type != BPF_MAP_TYPE_ARRAY &&
529 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
530 map->map_type != BPF_MAP_TYPE_SK_STORAGE)
531 return -ENOTSUPP;
532 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
533 map->value_size) {
534 WARN_ONCE(1,
535 "verifier bug spin_lock_off %d value_size %d\n",
536 map->spin_lock_off, map->value_size);
537 return -EFAULT;
538 }
539 }
540
541 if (map->ops->map_check_btf)
542 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
543
544 return ret;
545 }
546
547 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
548 /* called via syscall */
549 static int map_create(union bpf_attr *attr)
550 {
551 int numa_node = bpf_map_attr_numa_node(attr);
552 struct bpf_map *map;
553 int f_flags;
554 int err;
555
556 err = CHECK_ATTR(BPF_MAP_CREATE);
557 if (err)
558 return -EINVAL;
559
560 f_flags = bpf_get_file_flag(attr->map_flags);
561 if (f_flags < 0)
562 return f_flags;
563
564 if (numa_node != NUMA_NO_NODE &&
565 ((unsigned int)numa_node >= nr_node_ids ||
566 !node_online(numa_node)))
567 return -EINVAL;
568
569 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
570 map = find_and_alloc_map(attr);
571 if (IS_ERR(map))
572 return PTR_ERR(map);
573
574 err = bpf_obj_name_cpy(map->name, attr->map_name);
575 if (err)
576 goto free_map_nouncharge;
577
578 atomic_set(&map->refcnt, 1);
579 atomic_set(&map->usercnt, 1);
580
581 if (attr->btf_key_type_id || attr->btf_value_type_id) {
582 struct btf *btf;
583
584 if (!attr->btf_value_type_id) {
585 err = -EINVAL;
586 goto free_map_nouncharge;
587 }
588
589 btf = btf_get_by_fd(attr->btf_fd);
590 if (IS_ERR(btf)) {
591 err = PTR_ERR(btf);
592 goto free_map_nouncharge;
593 }
594
595 err = map_check_btf(map, btf, attr->btf_key_type_id,
596 attr->btf_value_type_id);
597 if (err) {
598 btf_put(btf);
599 goto free_map_nouncharge;
600 }
601
602 map->btf = btf;
603 map->btf_key_type_id = attr->btf_key_type_id;
604 map->btf_value_type_id = attr->btf_value_type_id;
605 } else {
606 map->spin_lock_off = -EINVAL;
607 }
608
609 err = security_bpf_map_alloc(map);
610 if (err)
611 goto free_map_nouncharge;
612
613 err = bpf_map_init_memlock(map);
614 if (err)
615 goto free_map_sec;
616
617 err = bpf_map_alloc_id(map);
618 if (err)
619 goto free_map;
620
621 err = bpf_map_new_fd(map, f_flags);
622 if (err < 0) {
623 /* failed to allocate fd.
624 * bpf_map_put_with_uref() is needed because the above
625 * bpf_map_alloc_id() has published the map
626 * to the userspace and the userspace may
627 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
628 */
629 bpf_map_put_with_uref(map);
630 return err;
631 }
632
633 return err;
634
635 free_map:
636 bpf_map_release_memlock(map);
637 free_map_sec:
638 security_bpf_map_free(map);
639 free_map_nouncharge:
640 btf_put(map->btf);
641 map->ops->map_free(map);
642 return err;
643 }
644
645 /* if error is returned, fd is released.
646 * On success caller should complete fd access with matching fdput()
647 */
648 struct bpf_map *__bpf_map_get(struct fd f)
649 {
650 if (!f.file)
651 return ERR_PTR(-EBADF);
652 if (f.file->f_op != &bpf_map_fops) {
653 fdput(f);
654 return ERR_PTR(-EINVAL);
655 }
656
657 return f.file->private_data;
658 }
659
660 /* prog's and map's refcnt limit */
661 #define BPF_MAX_REFCNT 32768
662
663 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
664 {
665 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
666 atomic_dec(&map->refcnt);
667 return ERR_PTR(-EBUSY);
668 }
669 if (uref)
670 atomic_inc(&map->usercnt);
671 return map;
672 }
673 EXPORT_SYMBOL_GPL(bpf_map_inc);
674
675 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
676 {
677 struct fd f = fdget(ufd);
678 struct bpf_map *map;
679
680 map = __bpf_map_get(f);
681 if (IS_ERR(map))
682 return map;
683
684 map = bpf_map_inc(map, true);
685 fdput(f);
686
687 return map;
688 }
689
690 /* map_idr_lock should have been held */
691 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
692 bool uref)
693 {
694 int refold;
695
696 refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
697
698 if (refold >= BPF_MAX_REFCNT) {
699 __bpf_map_put(map, false);
700 return ERR_PTR(-EBUSY);
701 }
702
703 if (!refold)
704 return ERR_PTR(-ENOENT);
705
706 if (uref)
707 atomic_inc(&map->usercnt);
708
709 return map;
710 }
711
712 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
713 {
714 return -ENOTSUPP;
715 }
716
717 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
718 {
719 if (key_size)
720 return memdup_user(ukey, key_size);
721
722 if (ukey)
723 return ERR_PTR(-EINVAL);
724
725 return NULL;
726 }
727
728 /* last field in 'union bpf_attr' used by this command */
729 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
730
731 static int map_lookup_elem(union bpf_attr *attr)
732 {
733 void __user *ukey = u64_to_user_ptr(attr->key);
734 void __user *uvalue = u64_to_user_ptr(attr->value);
735 int ufd = attr->map_fd;
736 struct bpf_map *map;
737 void *key, *value, *ptr;
738 u32 value_size;
739 struct fd f;
740 int err;
741
742 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
743 return -EINVAL;
744
745 if (attr->flags & ~BPF_F_LOCK)
746 return -EINVAL;
747
748 f = fdget(ufd);
749 map = __bpf_map_get(f);
750 if (IS_ERR(map))
751 return PTR_ERR(map);
752 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
753 err = -EPERM;
754 goto err_put;
755 }
756
757 if ((attr->flags & BPF_F_LOCK) &&
758 !map_value_has_spin_lock(map)) {
759 err = -EINVAL;
760 goto err_put;
761 }
762
763 key = __bpf_copy_key(ukey, map->key_size);
764 if (IS_ERR(key)) {
765 err = PTR_ERR(key);
766 goto err_put;
767 }
768
769 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
770 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
771 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
772 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
773 value_size = round_up(map->value_size, 8) * num_possible_cpus();
774 else if (IS_FD_MAP(map))
775 value_size = sizeof(u32);
776 else
777 value_size = map->value_size;
778
779 err = -ENOMEM;
780 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
781 if (!value)
782 goto free_key;
783
784 if (bpf_map_is_dev_bound(map)) {
785 err = bpf_map_offload_lookup_elem(map, key, value);
786 goto done;
787 }
788
789 preempt_disable();
790 this_cpu_inc(bpf_prog_active);
791 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
792 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
793 err = bpf_percpu_hash_copy(map, key, value);
794 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
795 err = bpf_percpu_array_copy(map, key, value);
796 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
797 err = bpf_percpu_cgroup_storage_copy(map, key, value);
798 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
799 err = bpf_stackmap_copy(map, key, value);
800 } else if (IS_FD_ARRAY(map)) {
801 err = bpf_fd_array_map_lookup_elem(map, key, value);
802 } else if (IS_FD_HASH(map)) {
803 err = bpf_fd_htab_map_lookup_elem(map, key, value);
804 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
805 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
806 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
807 map->map_type == BPF_MAP_TYPE_STACK) {
808 err = map->ops->map_peek_elem(map, value);
809 } else {
810 rcu_read_lock();
811 if (map->ops->map_lookup_elem_sys_only)
812 ptr = map->ops->map_lookup_elem_sys_only(map, key);
813 else
814 ptr = map->ops->map_lookup_elem(map, key);
815 if (IS_ERR(ptr)) {
816 err = PTR_ERR(ptr);
817 } else if (!ptr) {
818 err = -ENOENT;
819 } else {
820 err = 0;
821 if (attr->flags & BPF_F_LOCK)
822 /* lock 'ptr' and copy everything but lock */
823 copy_map_value_locked(map, value, ptr, true);
824 else
825 copy_map_value(map, value, ptr);
826 /* mask lock, since value wasn't zero inited */
827 check_and_init_map_lock(map, value);
828 }
829 rcu_read_unlock();
830 }
831 this_cpu_dec(bpf_prog_active);
832 preempt_enable();
833
834 done:
835 if (err)
836 goto free_value;
837
838 err = -EFAULT;
839 if (copy_to_user(uvalue, value, value_size) != 0)
840 goto free_value;
841
842 err = 0;
843
844 free_value:
845 kfree(value);
846 free_key:
847 kfree(key);
848 err_put:
849 fdput(f);
850 return err;
851 }
852
853 static void maybe_wait_bpf_programs(struct bpf_map *map)
854 {
855 /* Wait for any running BPF programs to complete so that
856 * userspace, when we return to it, knows that all programs
857 * that could be running use the new map value.
858 */
859 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
860 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
861 synchronize_rcu();
862 }
863
864 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
865
866 static int map_update_elem(union bpf_attr *attr)
867 {
868 void __user *ukey = u64_to_user_ptr(attr->key);
869 void __user *uvalue = u64_to_user_ptr(attr->value);
870 int ufd = attr->map_fd;
871 struct bpf_map *map;
872 void *key, *value;
873 u32 value_size;
874 struct fd f;
875 int err;
876
877 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
878 return -EINVAL;
879
880 f = fdget(ufd);
881 map = __bpf_map_get(f);
882 if (IS_ERR(map))
883 return PTR_ERR(map);
884 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
885 err = -EPERM;
886 goto err_put;
887 }
888
889 if ((attr->flags & BPF_F_LOCK) &&
890 !map_value_has_spin_lock(map)) {
891 err = -EINVAL;
892 goto err_put;
893 }
894
895 key = __bpf_copy_key(ukey, map->key_size);
896 if (IS_ERR(key)) {
897 err = PTR_ERR(key);
898 goto err_put;
899 }
900
901 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
902 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
903 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
904 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
905 value_size = round_up(map->value_size, 8) * num_possible_cpus();
906 else
907 value_size = map->value_size;
908
909 err = -ENOMEM;
910 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
911 if (!value)
912 goto free_key;
913
914 err = -EFAULT;
915 if (copy_from_user(value, uvalue, value_size) != 0)
916 goto free_value;
917
918 /* Need to create a kthread, thus must support schedule */
919 if (bpf_map_is_dev_bound(map)) {
920 err = bpf_map_offload_update_elem(map, key, value, attr->flags);
921 goto out;
922 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
923 map->map_type == BPF_MAP_TYPE_SOCKHASH ||
924 map->map_type == BPF_MAP_TYPE_SOCKMAP) {
925 err = map->ops->map_update_elem(map, key, value, attr->flags);
926 goto out;
927 }
928
929 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
930 * inside bpf map update or delete otherwise deadlocks are possible
931 */
932 preempt_disable();
933 __this_cpu_inc(bpf_prog_active);
934 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
935 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
936 err = bpf_percpu_hash_update(map, key, value, attr->flags);
937 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
938 err = bpf_percpu_array_update(map, key, value, attr->flags);
939 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
940 err = bpf_percpu_cgroup_storage_update(map, key, value,
941 attr->flags);
942 } else if (IS_FD_ARRAY(map)) {
943 rcu_read_lock();
944 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
945 attr->flags);
946 rcu_read_unlock();
947 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
948 rcu_read_lock();
949 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
950 attr->flags);
951 rcu_read_unlock();
952 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
953 /* rcu_read_lock() is not needed */
954 err = bpf_fd_reuseport_array_update_elem(map, key, value,
955 attr->flags);
956 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
957 map->map_type == BPF_MAP_TYPE_STACK) {
958 err = map->ops->map_push_elem(map, value, attr->flags);
959 } else {
960 rcu_read_lock();
961 err = map->ops->map_update_elem(map, key, value, attr->flags);
962 rcu_read_unlock();
963 }
964 __this_cpu_dec(bpf_prog_active);
965 preempt_enable();
966 maybe_wait_bpf_programs(map);
967 out:
968 free_value:
969 kfree(value);
970 free_key:
971 kfree(key);
972 err_put:
973 fdput(f);
974 return err;
975 }
976
977 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
978
979 static int map_delete_elem(union bpf_attr *attr)
980 {
981 void __user *ukey = u64_to_user_ptr(attr->key);
982 int ufd = attr->map_fd;
983 struct bpf_map *map;
984 struct fd f;
985 void *key;
986 int err;
987
988 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
989 return -EINVAL;
990
991 f = fdget(ufd);
992 map = __bpf_map_get(f);
993 if (IS_ERR(map))
994 return PTR_ERR(map);
995 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
996 err = -EPERM;
997 goto err_put;
998 }
999
1000 key = __bpf_copy_key(ukey, map->key_size);
1001 if (IS_ERR(key)) {
1002 err = PTR_ERR(key);
1003 goto err_put;
1004 }
1005
1006 if (bpf_map_is_dev_bound(map)) {
1007 err = bpf_map_offload_delete_elem(map, key);
1008 goto out;
1009 }
1010
1011 preempt_disable();
1012 __this_cpu_inc(bpf_prog_active);
1013 rcu_read_lock();
1014 err = map->ops->map_delete_elem(map, key);
1015 rcu_read_unlock();
1016 __this_cpu_dec(bpf_prog_active);
1017 preempt_enable();
1018 maybe_wait_bpf_programs(map);
1019 out:
1020 kfree(key);
1021 err_put:
1022 fdput(f);
1023 return err;
1024 }
1025
1026 /* last field in 'union bpf_attr' used by this command */
1027 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1028
1029 static int map_get_next_key(union bpf_attr *attr)
1030 {
1031 void __user *ukey = u64_to_user_ptr(attr->key);
1032 void __user *unext_key = u64_to_user_ptr(attr->next_key);
1033 int ufd = attr->map_fd;
1034 struct bpf_map *map;
1035 void *key, *next_key;
1036 struct fd f;
1037 int err;
1038
1039 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1040 return -EINVAL;
1041
1042 f = fdget(ufd);
1043 map = __bpf_map_get(f);
1044 if (IS_ERR(map))
1045 return PTR_ERR(map);
1046 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1047 err = -EPERM;
1048 goto err_put;
1049 }
1050
1051 if (ukey) {
1052 key = __bpf_copy_key(ukey, map->key_size);
1053 if (IS_ERR(key)) {
1054 err = PTR_ERR(key);
1055 goto err_put;
1056 }
1057 } else {
1058 key = NULL;
1059 }
1060
1061 err = -ENOMEM;
1062 next_key = kmalloc(map->key_size, GFP_USER);
1063 if (!next_key)
1064 goto free_key;
1065
1066 if (bpf_map_is_dev_bound(map)) {
1067 err = bpf_map_offload_get_next_key(map, key, next_key);
1068 goto out;
1069 }
1070
1071 rcu_read_lock();
1072 err = map->ops->map_get_next_key(map, key, next_key);
1073 rcu_read_unlock();
1074 out:
1075 if (err)
1076 goto free_next_key;
1077
1078 err = -EFAULT;
1079 if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1080 goto free_next_key;
1081
1082 err = 0;
1083
1084 free_next_key:
1085 kfree(next_key);
1086 free_key:
1087 kfree(key);
1088 err_put:
1089 fdput(f);
1090 return err;
1091 }
1092
1093 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1094
1095 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1096 {
1097 void __user *ukey = u64_to_user_ptr(attr->key);
1098 void __user *uvalue = u64_to_user_ptr(attr->value);
1099 int ufd = attr->map_fd;
1100 struct bpf_map *map;
1101 void *key, *value;
1102 u32 value_size;
1103 struct fd f;
1104 int err;
1105
1106 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1107 return -EINVAL;
1108
1109 f = fdget(ufd);
1110 map = __bpf_map_get(f);
1111 if (IS_ERR(map))
1112 return PTR_ERR(map);
1113 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1114 err = -EPERM;
1115 goto err_put;
1116 }
1117
1118 key = __bpf_copy_key(ukey, map->key_size);
1119 if (IS_ERR(key)) {
1120 err = PTR_ERR(key);
1121 goto err_put;
1122 }
1123
1124 value_size = map->value_size;
1125
1126 err = -ENOMEM;
1127 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1128 if (!value)
1129 goto free_key;
1130
1131 if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1132 map->map_type == BPF_MAP_TYPE_STACK) {
1133 err = map->ops->map_pop_elem(map, value);
1134 } else {
1135 err = -ENOTSUPP;
1136 }
1137
1138 if (err)
1139 goto free_value;
1140
1141 if (copy_to_user(uvalue, value, value_size) != 0)
1142 goto free_value;
1143
1144 err = 0;
1145
1146 free_value:
1147 kfree(value);
1148 free_key:
1149 kfree(key);
1150 err_put:
1151 fdput(f);
1152 return err;
1153 }
1154
1155 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1156
1157 static int map_freeze(const union bpf_attr *attr)
1158 {
1159 int err = 0, ufd = attr->map_fd;
1160 struct bpf_map *map;
1161 struct fd f;
1162
1163 if (CHECK_ATTR(BPF_MAP_FREEZE))
1164 return -EINVAL;
1165
1166 f = fdget(ufd);
1167 map = __bpf_map_get(f);
1168 if (IS_ERR(map))
1169 return PTR_ERR(map);
1170 if (READ_ONCE(map->frozen)) {
1171 err = -EBUSY;
1172 goto err_put;
1173 }
1174 if (!capable(CAP_SYS_ADMIN)) {
1175 err = -EPERM;
1176 goto err_put;
1177 }
1178
1179 WRITE_ONCE(map->frozen, true);
1180 err_put:
1181 fdput(f);
1182 return err;
1183 }
1184
1185 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1186 #define BPF_PROG_TYPE(_id, _name) \
1187 [_id] = & _name ## _prog_ops,
1188 #define BPF_MAP_TYPE(_id, _ops)
1189 #include <linux/bpf_types.h>
1190 #undef BPF_PROG_TYPE
1191 #undef BPF_MAP_TYPE
1192 };
1193
1194 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1195 {
1196 const struct bpf_prog_ops *ops;
1197
1198 if (type >= ARRAY_SIZE(bpf_prog_types))
1199 return -EINVAL;
1200 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1201 ops = bpf_prog_types[type];
1202 if (!ops)
1203 return -EINVAL;
1204
1205 if (!bpf_prog_is_dev_bound(prog->aux))
1206 prog->aux->ops = ops;
1207 else
1208 prog->aux->ops = &bpf_offload_prog_ops;
1209 prog->type = type;
1210 return 0;
1211 }
1212
1213 /* drop refcnt on maps used by eBPF program and free auxilary data */
1214 static void free_used_maps(struct bpf_prog_aux *aux)
1215 {
1216 enum bpf_cgroup_storage_type stype;
1217 int i;
1218
1219 for_each_cgroup_storage_type(stype) {
1220 if (!aux->cgroup_storage[stype])
1221 continue;
1222 bpf_cgroup_storage_release(aux->prog,
1223 aux->cgroup_storage[stype]);
1224 }
1225
1226 for (i = 0; i < aux->used_map_cnt; i++)
1227 bpf_map_put(aux->used_maps[i]);
1228
1229 kfree(aux->used_maps);
1230 }
1231
1232 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1233 {
1234 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1235 unsigned long user_bufs;
1236
1237 if (user) {
1238 user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1239 if (user_bufs > memlock_limit) {
1240 atomic_long_sub(pages, &user->locked_vm);
1241 return -EPERM;
1242 }
1243 }
1244
1245 return 0;
1246 }
1247
1248 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1249 {
1250 if (user)
1251 atomic_long_sub(pages, &user->locked_vm);
1252 }
1253
1254 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1255 {
1256 struct user_struct *user = get_current_user();
1257 int ret;
1258
1259 ret = __bpf_prog_charge(user, prog->pages);
1260 if (ret) {
1261 free_uid(user);
1262 return ret;
1263 }
1264
1265 prog->aux->user = user;
1266 return 0;
1267 }
1268
1269 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1270 {
1271 struct user_struct *user = prog->aux->user;
1272
1273 __bpf_prog_uncharge(user, prog->pages);
1274 free_uid(user);
1275 }
1276
1277 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1278 {
1279 int id;
1280
1281 idr_preload(GFP_KERNEL);
1282 spin_lock_bh(&prog_idr_lock);
1283 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1284 if (id > 0)
1285 prog->aux->id = id;
1286 spin_unlock_bh(&prog_idr_lock);
1287 idr_preload_end();
1288
1289 /* id is in [1, INT_MAX) */
1290 if (WARN_ON_ONCE(!id))
1291 return -ENOSPC;
1292
1293 return id > 0 ? 0 : id;
1294 }
1295
1296 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1297 {
1298 /* cBPF to eBPF migrations are currently not in the idr store.
1299 * Offloaded programs are removed from the store when their device
1300 * disappears - even if someone grabs an fd to them they are unusable,
1301 * simply waiting for refcnt to drop to be freed.
1302 */
1303 if (!prog->aux->id)
1304 return;
1305
1306 if (do_idr_lock)
1307 spin_lock_bh(&prog_idr_lock);
1308 else
1309 __acquire(&prog_idr_lock);
1310
1311 idr_remove(&prog_idr, prog->aux->id);
1312 prog->aux->id = 0;
1313
1314 if (do_idr_lock)
1315 spin_unlock_bh(&prog_idr_lock);
1316 else
1317 __release(&prog_idr_lock);
1318 }
1319
1320 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1321 {
1322 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1323
1324 free_used_maps(aux);
1325 bpf_prog_uncharge_memlock(aux->prog);
1326 security_bpf_prog_free(aux);
1327 bpf_prog_free(aux->prog);
1328 }
1329
1330 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1331 {
1332 if (atomic_dec_and_test(&prog->aux->refcnt)) {
1333 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1334 /* bpf_prog_free_id() must be called first */
1335 bpf_prog_free_id(prog, do_idr_lock);
1336 bpf_prog_kallsyms_del_all(prog);
1337 btf_put(prog->aux->btf);
1338 kvfree(prog->aux->func_info);
1339 bpf_prog_free_linfo(prog);
1340
1341 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1342 }
1343 }
1344
1345 void bpf_prog_put(struct bpf_prog *prog)
1346 {
1347 __bpf_prog_put(prog, true);
1348 }
1349 EXPORT_SYMBOL_GPL(bpf_prog_put);
1350
1351 static int bpf_prog_release(struct inode *inode, struct file *filp)
1352 {
1353 struct bpf_prog *prog = filp->private_data;
1354
1355 bpf_prog_put(prog);
1356 return 0;
1357 }
1358
1359 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1360 struct bpf_prog_stats *stats)
1361 {
1362 u64 nsecs = 0, cnt = 0;
1363 int cpu;
1364
1365 for_each_possible_cpu(cpu) {
1366 const struct bpf_prog_stats *st;
1367 unsigned int start;
1368 u64 tnsecs, tcnt;
1369
1370 st = per_cpu_ptr(prog->aux->stats, cpu);
1371 do {
1372 start = u64_stats_fetch_begin_irq(&st->syncp);
1373 tnsecs = st->nsecs;
1374 tcnt = st->cnt;
1375 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1376 nsecs += tnsecs;
1377 cnt += tcnt;
1378 }
1379 stats->nsecs = nsecs;
1380 stats->cnt = cnt;
1381 }
1382
1383 #ifdef CONFIG_PROC_FS
1384 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1385 {
1386 const struct bpf_prog *prog = filp->private_data;
1387 char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1388 struct bpf_prog_stats stats;
1389
1390 bpf_prog_get_stats(prog, &stats);
1391 bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1392 seq_printf(m,
1393 "prog_type:\t%u\n"
1394 "prog_jited:\t%u\n"
1395 "prog_tag:\t%s\n"
1396 "memlock:\t%llu\n"
1397 "prog_id:\t%u\n"
1398 "run_time_ns:\t%llu\n"
1399 "run_cnt:\t%llu\n",
1400 prog->type,
1401 prog->jited,
1402 prog_tag,
1403 prog->pages * 1ULL << PAGE_SHIFT,
1404 prog->aux->id,
1405 stats.nsecs,
1406 stats.cnt);
1407 }
1408 #endif
1409
1410 const struct file_operations bpf_prog_fops = {
1411 #ifdef CONFIG_PROC_FS
1412 .show_fdinfo = bpf_prog_show_fdinfo,
1413 #endif
1414 .release = bpf_prog_release,
1415 .read = bpf_dummy_read,
1416 .write = bpf_dummy_write,
1417 };
1418
1419 int bpf_prog_new_fd(struct bpf_prog *prog)
1420 {
1421 int ret;
1422
1423 ret = security_bpf_prog(prog);
1424 if (ret < 0)
1425 return ret;
1426
1427 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1428 O_RDWR | O_CLOEXEC);
1429 }
1430
1431 static struct bpf_prog *____bpf_prog_get(struct fd f)
1432 {
1433 if (!f.file)
1434 return ERR_PTR(-EBADF);
1435 if (f.file->f_op != &bpf_prog_fops) {
1436 fdput(f);
1437 return ERR_PTR(-EINVAL);
1438 }
1439
1440 return f.file->private_data;
1441 }
1442
1443 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1444 {
1445 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1446 atomic_sub(i, &prog->aux->refcnt);
1447 return ERR_PTR(-EBUSY);
1448 }
1449 return prog;
1450 }
1451 EXPORT_SYMBOL_GPL(bpf_prog_add);
1452
1453 void bpf_prog_sub(struct bpf_prog *prog, int i)
1454 {
1455 /* Only to be used for undoing previous bpf_prog_add() in some
1456 * error path. We still know that another entity in our call
1457 * path holds a reference to the program, thus atomic_sub() can
1458 * be safely used in such cases!
1459 */
1460 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1461 }
1462 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1463
1464 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1465 {
1466 return bpf_prog_add(prog, 1);
1467 }
1468 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1469
1470 /* prog_idr_lock should have been held */
1471 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1472 {
1473 int refold;
1474
1475 refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1476
1477 if (refold >= BPF_MAX_REFCNT) {
1478 __bpf_prog_put(prog, false);
1479 return ERR_PTR(-EBUSY);
1480 }
1481
1482 if (!refold)
1483 return ERR_PTR(-ENOENT);
1484
1485 return prog;
1486 }
1487 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1488
1489 bool bpf_prog_get_ok(struct bpf_prog *prog,
1490 enum bpf_prog_type *attach_type, bool attach_drv)
1491 {
1492 /* not an attachment, just a refcount inc, always allow */
1493 if (!attach_type)
1494 return true;
1495
1496 if (prog->type != *attach_type)
1497 return false;
1498 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1499 return false;
1500
1501 return true;
1502 }
1503
1504 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1505 bool attach_drv)
1506 {
1507 struct fd f = fdget(ufd);
1508 struct bpf_prog *prog;
1509
1510 prog = ____bpf_prog_get(f);
1511 if (IS_ERR(prog))
1512 return prog;
1513 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1514 prog = ERR_PTR(-EINVAL);
1515 goto out;
1516 }
1517
1518 prog = bpf_prog_inc(prog);
1519 out:
1520 fdput(f);
1521 return prog;
1522 }
1523
1524 struct bpf_prog *bpf_prog_get(u32 ufd)
1525 {
1526 return __bpf_prog_get(ufd, NULL, false);
1527 }
1528
1529 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1530 bool attach_drv)
1531 {
1532 return __bpf_prog_get(ufd, &type, attach_drv);
1533 }
1534 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1535
1536 /* Initially all BPF programs could be loaded w/o specifying
1537 * expected_attach_type. Later for some of them specifying expected_attach_type
1538 * at load time became required so that program could be validated properly.
1539 * Programs of types that are allowed to be loaded both w/ and w/o (for
1540 * backward compatibility) expected_attach_type, should have the default attach
1541 * type assigned to expected_attach_type for the latter case, so that it can be
1542 * validated later at attach time.
1543 *
1544 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1545 * prog type requires it but has some attach types that have to be backward
1546 * compatible.
1547 */
1548 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1549 {
1550 switch (attr->prog_type) {
1551 case BPF_PROG_TYPE_CGROUP_SOCK:
1552 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1553 * exist so checking for non-zero is the way to go here.
1554 */
1555 if (!attr->expected_attach_type)
1556 attr->expected_attach_type =
1557 BPF_CGROUP_INET_SOCK_CREATE;
1558 break;
1559 }
1560 }
1561
1562 static int
1563 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1564 enum bpf_attach_type expected_attach_type)
1565 {
1566 switch (prog_type) {
1567 case BPF_PROG_TYPE_CGROUP_SOCK:
1568 switch (expected_attach_type) {
1569 case BPF_CGROUP_INET_SOCK_CREATE:
1570 case BPF_CGROUP_INET4_POST_BIND:
1571 case BPF_CGROUP_INET6_POST_BIND:
1572 return 0;
1573 default:
1574 return -EINVAL;
1575 }
1576 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1577 switch (expected_attach_type) {
1578 case BPF_CGROUP_INET4_BIND:
1579 case BPF_CGROUP_INET6_BIND:
1580 case BPF_CGROUP_INET4_CONNECT:
1581 case BPF_CGROUP_INET6_CONNECT:
1582 case BPF_CGROUP_UDP4_SENDMSG:
1583 case BPF_CGROUP_UDP6_SENDMSG:
1584 return 0;
1585 default:
1586 return -EINVAL;
1587 }
1588 default:
1589 return 0;
1590 }
1591 }
1592
1593 /* last field in 'union bpf_attr' used by this command */
1594 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt
1595
1596 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
1597 {
1598 enum bpf_prog_type type = attr->prog_type;
1599 struct bpf_prog *prog;
1600 int err;
1601 char license[128];
1602 bool is_gpl;
1603
1604 if (CHECK_ATTR(BPF_PROG_LOAD))
1605 return -EINVAL;
1606
1607 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | BPF_F_ANY_ALIGNMENT))
1608 return -EINVAL;
1609
1610 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
1611 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
1612 !capable(CAP_SYS_ADMIN))
1613 return -EPERM;
1614
1615 /* copy eBPF program license from user space */
1616 if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1617 sizeof(license) - 1) < 0)
1618 return -EFAULT;
1619 license[sizeof(license) - 1] = 0;
1620
1621 /* eBPF programs must be GPL compatible to use GPL-ed functions */
1622 is_gpl = license_is_gpl_compatible(license);
1623
1624 if (attr->insn_cnt == 0 ||
1625 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
1626 return -E2BIG;
1627 if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1628 type != BPF_PROG_TYPE_CGROUP_SKB &&
1629 !capable(CAP_SYS_ADMIN))
1630 return -EPERM;
1631
1632 bpf_prog_load_fixup_attach_type(attr);
1633 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1634 return -EINVAL;
1635
1636 /* plain bpf_prog allocation */
1637 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1638 if (!prog)
1639 return -ENOMEM;
1640
1641 prog->expected_attach_type = attr->expected_attach_type;
1642
1643 prog->aux->offload_requested = !!attr->prog_ifindex;
1644
1645 err = security_bpf_prog_alloc(prog->aux);
1646 if (err)
1647 goto free_prog_nouncharge;
1648
1649 err = bpf_prog_charge_memlock(prog);
1650 if (err)
1651 goto free_prog_sec;
1652
1653 prog->len = attr->insn_cnt;
1654
1655 err = -EFAULT;
1656 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1657 bpf_prog_insn_size(prog)) != 0)
1658 goto free_prog;
1659
1660 prog->orig_prog = NULL;
1661 prog->jited = 0;
1662
1663 atomic_set(&prog->aux->refcnt, 1);
1664 prog->gpl_compatible = is_gpl ? 1 : 0;
1665
1666 if (bpf_prog_is_dev_bound(prog->aux)) {
1667 err = bpf_prog_offload_init(prog, attr);
1668 if (err)
1669 goto free_prog;
1670 }
1671
1672 /* find program type: socket_filter vs tracing_filter */
1673 err = find_prog_type(type, prog);
1674 if (err < 0)
1675 goto free_prog;
1676
1677 prog->aux->load_time = ktime_get_boot_ns();
1678 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1679 if (err)
1680 goto free_prog;
1681
1682 /* run eBPF verifier */
1683 err = bpf_check(&prog, attr, uattr);
1684 if (err < 0)
1685 goto free_used_maps;
1686
1687 prog = bpf_prog_select_runtime(prog, &err);
1688 if (err < 0)
1689 goto free_used_maps;
1690
1691 err = bpf_prog_alloc_id(prog);
1692 if (err)
1693 goto free_used_maps;
1694
1695 err = bpf_prog_new_fd(prog);
1696 if (err < 0) {
1697 /* failed to allocate fd.
1698 * bpf_prog_put() is needed because the above
1699 * bpf_prog_alloc_id() has published the prog
1700 * to the userspace and the userspace may
1701 * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
1702 */
1703 bpf_prog_put(prog);
1704 return err;
1705 }
1706
1707 bpf_prog_kallsyms_add(prog);
1708 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
1709 return err;
1710
1711 free_used_maps:
1712 bpf_prog_free_linfo(prog);
1713 kvfree(prog->aux->func_info);
1714 btf_put(prog->aux->btf);
1715 bpf_prog_kallsyms_del_subprogs(prog);
1716 free_used_maps(prog->aux);
1717 free_prog:
1718 bpf_prog_uncharge_memlock(prog);
1719 free_prog_sec:
1720 security_bpf_prog_free(prog->aux);
1721 free_prog_nouncharge:
1722 bpf_prog_free(prog);
1723 return err;
1724 }
1725
1726 #define BPF_OBJ_LAST_FIELD file_flags
1727
1728 static int bpf_obj_pin(const union bpf_attr *attr)
1729 {
1730 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1731 return -EINVAL;
1732
1733 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1734 }
1735
1736 static int bpf_obj_get(const union bpf_attr *attr)
1737 {
1738 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1739 attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1740 return -EINVAL;
1741
1742 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1743 attr->file_flags);
1744 }
1745
1746 struct bpf_raw_tracepoint {
1747 struct bpf_raw_event_map *btp;
1748 struct bpf_prog *prog;
1749 };
1750
1751 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1752 {
1753 struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1754
1755 if (raw_tp->prog) {
1756 bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1757 bpf_prog_put(raw_tp->prog);
1758 }
1759 bpf_put_raw_tracepoint(raw_tp->btp);
1760 kfree(raw_tp);
1761 return 0;
1762 }
1763
1764 static const struct file_operations bpf_raw_tp_fops = {
1765 .release = bpf_raw_tracepoint_release,
1766 .read = bpf_dummy_read,
1767 .write = bpf_dummy_write,
1768 };
1769
1770 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1771
1772 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1773 {
1774 struct bpf_raw_tracepoint *raw_tp;
1775 struct bpf_raw_event_map *btp;
1776 struct bpf_prog *prog;
1777 char tp_name[128];
1778 int tp_fd, err;
1779
1780 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1781 sizeof(tp_name) - 1) < 0)
1782 return -EFAULT;
1783 tp_name[sizeof(tp_name) - 1] = 0;
1784
1785 btp = bpf_get_raw_tracepoint(tp_name);
1786 if (!btp)
1787 return -ENOENT;
1788
1789 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1790 if (!raw_tp) {
1791 err = -ENOMEM;
1792 goto out_put_btp;
1793 }
1794 raw_tp->btp = btp;
1795
1796 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
1797 if (IS_ERR(prog)) {
1798 err = PTR_ERR(prog);
1799 goto out_free_tp;
1800 }
1801 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
1802 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
1803 err = -EINVAL;
1804 goto out_put_prog;
1805 }
1806
1807 err = bpf_probe_register(raw_tp->btp, prog);
1808 if (err)
1809 goto out_put_prog;
1810
1811 raw_tp->prog = prog;
1812 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1813 O_CLOEXEC);
1814 if (tp_fd < 0) {
1815 bpf_probe_unregister(raw_tp->btp, prog);
1816 err = tp_fd;
1817 goto out_put_prog;
1818 }
1819 return tp_fd;
1820
1821 out_put_prog:
1822 bpf_prog_put(prog);
1823 out_free_tp:
1824 kfree(raw_tp);
1825 out_put_btp:
1826 bpf_put_raw_tracepoint(btp);
1827 return err;
1828 }
1829
1830 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1831 enum bpf_attach_type attach_type)
1832 {
1833 switch (prog->type) {
1834 case BPF_PROG_TYPE_CGROUP_SOCK:
1835 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1836 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1837 default:
1838 return 0;
1839 }
1840 }
1841
1842 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1843
1844 #define BPF_F_ATTACH_MASK \
1845 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1846
1847 static int bpf_prog_attach(const union bpf_attr *attr)
1848 {
1849 enum bpf_prog_type ptype;
1850 struct bpf_prog *prog;
1851 int ret;
1852
1853 if (!capable(CAP_NET_ADMIN))
1854 return -EPERM;
1855
1856 if (CHECK_ATTR(BPF_PROG_ATTACH))
1857 return -EINVAL;
1858
1859 if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1860 return -EINVAL;
1861
1862 switch (attr->attach_type) {
1863 case BPF_CGROUP_INET_INGRESS:
1864 case BPF_CGROUP_INET_EGRESS:
1865 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1866 break;
1867 case BPF_CGROUP_INET_SOCK_CREATE:
1868 case BPF_CGROUP_INET4_POST_BIND:
1869 case BPF_CGROUP_INET6_POST_BIND:
1870 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1871 break;
1872 case BPF_CGROUP_INET4_BIND:
1873 case BPF_CGROUP_INET6_BIND:
1874 case BPF_CGROUP_INET4_CONNECT:
1875 case BPF_CGROUP_INET6_CONNECT:
1876 case BPF_CGROUP_UDP4_SENDMSG:
1877 case BPF_CGROUP_UDP6_SENDMSG:
1878 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1879 break;
1880 case BPF_CGROUP_SOCK_OPS:
1881 ptype = BPF_PROG_TYPE_SOCK_OPS;
1882 break;
1883 case BPF_CGROUP_DEVICE:
1884 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1885 break;
1886 case BPF_SK_MSG_VERDICT:
1887 ptype = BPF_PROG_TYPE_SK_MSG;
1888 break;
1889 case BPF_SK_SKB_STREAM_PARSER:
1890 case BPF_SK_SKB_STREAM_VERDICT:
1891 ptype = BPF_PROG_TYPE_SK_SKB;
1892 break;
1893 case BPF_LIRC_MODE2:
1894 ptype = BPF_PROG_TYPE_LIRC_MODE2;
1895 break;
1896 case BPF_FLOW_DISSECTOR:
1897 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1898 break;
1899 case BPF_CGROUP_SYSCTL:
1900 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
1901 break;
1902 default:
1903 return -EINVAL;
1904 }
1905
1906 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1907 if (IS_ERR(prog))
1908 return PTR_ERR(prog);
1909
1910 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1911 bpf_prog_put(prog);
1912 return -EINVAL;
1913 }
1914
1915 switch (ptype) {
1916 case BPF_PROG_TYPE_SK_SKB:
1917 case BPF_PROG_TYPE_SK_MSG:
1918 ret = sock_map_get_from_fd(attr, prog);
1919 break;
1920 case BPF_PROG_TYPE_LIRC_MODE2:
1921 ret = lirc_prog_attach(attr, prog);
1922 break;
1923 case BPF_PROG_TYPE_FLOW_DISSECTOR:
1924 ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1925 break;
1926 default:
1927 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1928 }
1929
1930 if (ret)
1931 bpf_prog_put(prog);
1932 return ret;
1933 }
1934
1935 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1936
1937 static int bpf_prog_detach(const union bpf_attr *attr)
1938 {
1939 enum bpf_prog_type ptype;
1940
1941 if (!capable(CAP_NET_ADMIN))
1942 return -EPERM;
1943
1944 if (CHECK_ATTR(BPF_PROG_DETACH))
1945 return -EINVAL;
1946
1947 switch (attr->attach_type) {
1948 case BPF_CGROUP_INET_INGRESS:
1949 case BPF_CGROUP_INET_EGRESS:
1950 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1951 break;
1952 case BPF_CGROUP_INET_SOCK_CREATE:
1953 case BPF_CGROUP_INET4_POST_BIND:
1954 case BPF_CGROUP_INET6_POST_BIND:
1955 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1956 break;
1957 case BPF_CGROUP_INET4_BIND:
1958 case BPF_CGROUP_INET6_BIND:
1959 case BPF_CGROUP_INET4_CONNECT:
1960 case BPF_CGROUP_INET6_CONNECT:
1961 case BPF_CGROUP_UDP4_SENDMSG:
1962 case BPF_CGROUP_UDP6_SENDMSG:
1963 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1964 break;
1965 case BPF_CGROUP_SOCK_OPS:
1966 ptype = BPF_PROG_TYPE_SOCK_OPS;
1967 break;
1968 case BPF_CGROUP_DEVICE:
1969 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1970 break;
1971 case BPF_SK_MSG_VERDICT:
1972 return sock_map_get_from_fd(attr, NULL);
1973 case BPF_SK_SKB_STREAM_PARSER:
1974 case BPF_SK_SKB_STREAM_VERDICT:
1975 return sock_map_get_from_fd(attr, NULL);
1976 case BPF_LIRC_MODE2:
1977 return lirc_prog_detach(attr);
1978 case BPF_FLOW_DISSECTOR:
1979 return skb_flow_dissector_bpf_prog_detach(attr);
1980 case BPF_CGROUP_SYSCTL:
1981 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
1982 break;
1983 default:
1984 return -EINVAL;
1985 }
1986
1987 return cgroup_bpf_prog_detach(attr, ptype);
1988 }
1989
1990 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
1991
1992 static int bpf_prog_query(const union bpf_attr *attr,
1993 union bpf_attr __user *uattr)
1994 {
1995 if (!capable(CAP_NET_ADMIN))
1996 return -EPERM;
1997 if (CHECK_ATTR(BPF_PROG_QUERY))
1998 return -EINVAL;
1999 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
2000 return -EINVAL;
2001
2002 switch (attr->query.attach_type) {
2003 case BPF_CGROUP_INET_INGRESS:
2004 case BPF_CGROUP_INET_EGRESS:
2005 case BPF_CGROUP_INET_SOCK_CREATE:
2006 case BPF_CGROUP_INET4_BIND:
2007 case BPF_CGROUP_INET6_BIND:
2008 case BPF_CGROUP_INET4_POST_BIND:
2009 case BPF_CGROUP_INET6_POST_BIND:
2010 case BPF_CGROUP_INET4_CONNECT:
2011 case BPF_CGROUP_INET6_CONNECT:
2012 case BPF_CGROUP_UDP4_SENDMSG:
2013 case BPF_CGROUP_UDP6_SENDMSG:
2014 case BPF_CGROUP_SOCK_OPS:
2015 case BPF_CGROUP_DEVICE:
2016 case BPF_CGROUP_SYSCTL:
2017 break;
2018 case BPF_LIRC_MODE2:
2019 return lirc_prog_query(attr, uattr);
2020 case BPF_FLOW_DISSECTOR:
2021 return skb_flow_dissector_prog_query(attr, uattr);
2022 default:
2023 return -EINVAL;
2024 }
2025
2026 return cgroup_bpf_prog_query(attr, uattr);
2027 }
2028
2029 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
2030
2031 static int bpf_prog_test_run(const union bpf_attr *attr,
2032 union bpf_attr __user *uattr)
2033 {
2034 struct bpf_prog *prog;
2035 int ret = -ENOTSUPP;
2036
2037 if (!capable(CAP_SYS_ADMIN))
2038 return -EPERM;
2039 if (CHECK_ATTR(BPF_PROG_TEST_RUN))
2040 return -EINVAL;
2041
2042 if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
2043 (!attr->test.ctx_size_in && attr->test.ctx_in))
2044 return -EINVAL;
2045
2046 if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
2047 (!attr->test.ctx_size_out && attr->test.ctx_out))
2048 return -EINVAL;
2049
2050 prog = bpf_prog_get(attr->test.prog_fd);
2051 if (IS_ERR(prog))
2052 return PTR_ERR(prog);
2053
2054 if (prog->aux->ops->test_run)
2055 ret = prog->aux->ops->test_run(prog, attr, uattr);
2056
2057 bpf_prog_put(prog);
2058 return ret;
2059 }
2060
2061 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
2062
2063 static int bpf_obj_get_next_id(const union bpf_attr *attr,
2064 union bpf_attr __user *uattr,
2065 struct idr *idr,
2066 spinlock_t *lock)
2067 {
2068 u32 next_id = attr->start_id;
2069 int err = 0;
2070
2071 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
2072 return -EINVAL;
2073
2074 if (!capable(CAP_SYS_ADMIN))
2075 return -EPERM;
2076
2077 next_id++;
2078 spin_lock_bh(lock);
2079 if (!idr_get_next(idr, &next_id))
2080 err = -ENOENT;
2081 spin_unlock_bh(lock);
2082
2083 if (!err)
2084 err = put_user(next_id, &uattr->next_id);
2085
2086 return err;
2087 }
2088
2089 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
2090
2091 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
2092 {
2093 struct bpf_prog *prog;
2094 u32 id = attr->prog_id;
2095 int fd;
2096
2097 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
2098 return -EINVAL;
2099
2100 if (!capable(CAP_SYS_ADMIN))
2101 return -EPERM;
2102
2103 spin_lock_bh(&prog_idr_lock);
2104 prog = idr_find(&prog_idr, id);
2105 if (prog)
2106 prog = bpf_prog_inc_not_zero(prog);
2107 else
2108 prog = ERR_PTR(-ENOENT);
2109 spin_unlock_bh(&prog_idr_lock);
2110
2111 if (IS_ERR(prog))
2112 return PTR_ERR(prog);
2113
2114 fd = bpf_prog_new_fd(prog);
2115 if (fd < 0)
2116 bpf_prog_put(prog);
2117
2118 return fd;
2119 }
2120
2121 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
2122
2123 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
2124 {
2125 struct bpf_map *map;
2126 u32 id = attr->map_id;
2127 int f_flags;
2128 int fd;
2129
2130 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
2131 attr->open_flags & ~BPF_OBJ_FLAG_MASK)
2132 return -EINVAL;
2133
2134 if (!capable(CAP_SYS_ADMIN))
2135 return -EPERM;
2136
2137 f_flags = bpf_get_file_flag(attr->open_flags);
2138 if (f_flags < 0)
2139 return f_flags;
2140
2141 spin_lock_bh(&map_idr_lock);
2142 map = idr_find(&map_idr, id);
2143 if (map)
2144 map = bpf_map_inc_not_zero(map, true);
2145 else
2146 map = ERR_PTR(-ENOENT);
2147 spin_unlock_bh(&map_idr_lock);
2148
2149 if (IS_ERR(map))
2150 return PTR_ERR(map);
2151
2152 fd = bpf_map_new_fd(map, f_flags);
2153 if (fd < 0)
2154 bpf_map_put_with_uref(map);
2155
2156 return fd;
2157 }
2158
2159 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
2160 unsigned long addr, u32 *off,
2161 u32 *type)
2162 {
2163 const struct bpf_map *map;
2164 int i;
2165
2166 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
2167 map = prog->aux->used_maps[i];
2168 if (map == (void *)addr) {
2169 *type = BPF_PSEUDO_MAP_FD;
2170 return map;
2171 }
2172 if (!map->ops->map_direct_value_meta)
2173 continue;
2174 if (!map->ops->map_direct_value_meta(map, addr, off)) {
2175 *type = BPF_PSEUDO_MAP_VALUE;
2176 return map;
2177 }
2178 }
2179
2180 return NULL;
2181 }
2182
2183 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
2184 {
2185 const struct bpf_map *map;
2186 struct bpf_insn *insns;
2187 u32 off, type;
2188 u64 imm;
2189 int i;
2190
2191 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
2192 GFP_USER);
2193 if (!insns)
2194 return insns;
2195
2196 for (i = 0; i < prog->len; i++) {
2197 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
2198 insns[i].code = BPF_JMP | BPF_CALL;
2199 insns[i].imm = BPF_FUNC_tail_call;
2200 /* fall-through */
2201 }
2202 if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2203 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2204 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2205 insns[i].code = BPF_JMP | BPF_CALL;
2206 if (!bpf_dump_raw_ok())
2207 insns[i].imm = 0;
2208 continue;
2209 }
2210
2211 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2212 continue;
2213
2214 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2215 map = bpf_map_from_imm(prog, imm, &off, &type);
2216 if (map) {
2217 insns[i].src_reg = type;
2218 insns[i].imm = map->id;
2219 insns[i + 1].imm = off;
2220 continue;
2221 }
2222 }
2223
2224 return insns;
2225 }
2226
2227 static int set_info_rec_size(struct bpf_prog_info *info)
2228 {
2229 /*
2230 * Ensure info.*_rec_size is the same as kernel expected size
2231 *
2232 * or
2233 *
2234 * Only allow zero *_rec_size if both _rec_size and _cnt are
2235 * zero. In this case, the kernel will set the expected
2236 * _rec_size back to the info.
2237 */
2238
2239 if ((info->nr_func_info || info->func_info_rec_size) &&
2240 info->func_info_rec_size != sizeof(struct bpf_func_info))
2241 return -EINVAL;
2242
2243 if ((info->nr_line_info || info->line_info_rec_size) &&
2244 info->line_info_rec_size != sizeof(struct bpf_line_info))
2245 return -EINVAL;
2246
2247 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
2248 info->jited_line_info_rec_size != sizeof(__u64))
2249 return -EINVAL;
2250
2251 info->func_info_rec_size = sizeof(struct bpf_func_info);
2252 info->line_info_rec_size = sizeof(struct bpf_line_info);
2253 info->jited_line_info_rec_size = sizeof(__u64);
2254
2255 return 0;
2256 }
2257
2258 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
2259 const union bpf_attr *attr,
2260 union bpf_attr __user *uattr)
2261 {
2262 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2263 struct bpf_prog_info info = {};
2264 u32 info_len = attr->info.info_len;
2265 struct bpf_prog_stats stats;
2266 char __user *uinsns;
2267 u32 ulen;
2268 int err;
2269
2270 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2271 if (err)
2272 return err;
2273 info_len = min_t(u32, sizeof(info), info_len);
2274
2275 if (copy_from_user(&info, uinfo, info_len))
2276 return -EFAULT;
2277
2278 info.type = prog->type;
2279 info.id = prog->aux->id;
2280 info.load_time = prog->aux->load_time;
2281 info.created_by_uid = from_kuid_munged(current_user_ns(),
2282 prog->aux->user->uid);
2283 info.gpl_compatible = prog->gpl_compatible;
2284
2285 memcpy(info.tag, prog->tag, sizeof(prog->tag));
2286 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2287
2288 ulen = info.nr_map_ids;
2289 info.nr_map_ids = prog->aux->used_map_cnt;
2290 ulen = min_t(u32, info.nr_map_ids, ulen);
2291 if (ulen) {
2292 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2293 u32 i;
2294
2295 for (i = 0; i < ulen; i++)
2296 if (put_user(prog->aux->used_maps[i]->id,
2297 &user_map_ids[i]))
2298 return -EFAULT;
2299 }
2300
2301 err = set_info_rec_size(&info);
2302 if (err)
2303 return err;
2304
2305 bpf_prog_get_stats(prog, &stats);
2306 info.run_time_ns = stats.nsecs;
2307 info.run_cnt = stats.cnt;
2308
2309 if (!capable(CAP_SYS_ADMIN)) {
2310 info.jited_prog_len = 0;
2311 info.xlated_prog_len = 0;
2312 info.nr_jited_ksyms = 0;
2313 info.nr_jited_func_lens = 0;
2314 info.nr_func_info = 0;
2315 info.nr_line_info = 0;
2316 info.nr_jited_line_info = 0;
2317 goto done;
2318 }
2319
2320 ulen = info.xlated_prog_len;
2321 info.xlated_prog_len = bpf_prog_insn_size(prog);
2322 if (info.xlated_prog_len && ulen) {
2323 struct bpf_insn *insns_sanitized;
2324 bool fault;
2325
2326 if (prog->blinded && !bpf_dump_raw_ok()) {
2327 info.xlated_prog_insns = 0;
2328 goto done;
2329 }
2330 insns_sanitized = bpf_insn_prepare_dump(prog);
2331 if (!insns_sanitized)
2332 return -ENOMEM;
2333 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2334 ulen = min_t(u32, info.xlated_prog_len, ulen);
2335 fault = copy_to_user(uinsns, insns_sanitized, ulen);
2336 kfree(insns_sanitized);
2337 if (fault)
2338 return -EFAULT;
2339 }
2340
2341 if (bpf_prog_is_dev_bound(prog->aux)) {
2342 err = bpf_prog_offload_info_fill(&info, prog);
2343 if (err)
2344 return err;
2345 goto done;
2346 }
2347
2348 /* NOTE: the following code is supposed to be skipped for offload.
2349 * bpf_prog_offload_info_fill() is the place to fill similar fields
2350 * for offload.
2351 */
2352 ulen = info.jited_prog_len;
2353 if (prog->aux->func_cnt) {
2354 u32 i;
2355
2356 info.jited_prog_len = 0;
2357 for (i = 0; i < prog->aux->func_cnt; i++)
2358 info.jited_prog_len += prog->aux->func[i]->jited_len;
2359 } else {
2360 info.jited_prog_len = prog->jited_len;
2361 }
2362
2363 if (info.jited_prog_len && ulen) {
2364 if (bpf_dump_raw_ok()) {
2365 uinsns = u64_to_user_ptr(info.jited_prog_insns);
2366 ulen = min_t(u32, info.jited_prog_len, ulen);
2367
2368 /* for multi-function programs, copy the JITed
2369 * instructions for all the functions
2370 */
2371 if (prog->aux->func_cnt) {
2372 u32 len, free, i;
2373 u8 *img;
2374
2375 free = ulen;
2376 for (i = 0; i < prog->aux->func_cnt; i++) {
2377 len = prog->aux->func[i]->jited_len;
2378 len = min_t(u32, len, free);
2379 img = (u8 *) prog->aux->func[i]->bpf_func;
2380 if (copy_to_user(uinsns, img, len))
2381 return -EFAULT;
2382 uinsns += len;
2383 free -= len;
2384 if (!free)
2385 break;
2386 }
2387 } else {
2388 if (copy_to_user(uinsns, prog->bpf_func, ulen))
2389 return -EFAULT;
2390 }
2391 } else {
2392 info.jited_prog_insns = 0;
2393 }
2394 }
2395
2396 ulen = info.nr_jited_ksyms;
2397 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2398 if (ulen) {
2399 if (bpf_dump_raw_ok()) {
2400 unsigned long ksym_addr;
2401 u64 __user *user_ksyms;
2402 u32 i;
2403
2404 /* copy the address of the kernel symbol
2405 * corresponding to each function
2406 */
2407 ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2408 user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2409 if (prog->aux->func_cnt) {
2410 for (i = 0; i < ulen; i++) {
2411 ksym_addr = (unsigned long)
2412 prog->aux->func[i]->bpf_func;
2413 if (put_user((u64) ksym_addr,
2414 &user_ksyms[i]))
2415 return -EFAULT;
2416 }
2417 } else {
2418 ksym_addr = (unsigned long) prog->bpf_func;
2419 if (put_user((u64) ksym_addr, &user_ksyms[0]))
2420 return -EFAULT;
2421 }
2422 } else {
2423 info.jited_ksyms = 0;
2424 }
2425 }
2426
2427 ulen = info.nr_jited_func_lens;
2428 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2429 if (ulen) {
2430 if (bpf_dump_raw_ok()) {
2431 u32 __user *user_lens;
2432 u32 func_len, i;
2433
2434 /* copy the JITed image lengths for each function */
2435 ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2436 user_lens = u64_to_user_ptr(info.jited_func_lens);
2437 if (prog->aux->func_cnt) {
2438 for (i = 0; i < ulen; i++) {
2439 func_len =
2440 prog->aux->func[i]->jited_len;
2441 if (put_user(func_len, &user_lens[i]))
2442 return -EFAULT;
2443 }
2444 } else {
2445 func_len = prog->jited_len;
2446 if (put_user(func_len, &user_lens[0]))
2447 return -EFAULT;
2448 }
2449 } else {
2450 info.jited_func_lens = 0;
2451 }
2452 }
2453
2454 if (prog->aux->btf)
2455 info.btf_id = btf_id(prog->aux->btf);
2456
2457 ulen = info.nr_func_info;
2458 info.nr_func_info = prog->aux->func_info_cnt;
2459 if (info.nr_func_info && ulen) {
2460 char __user *user_finfo;
2461
2462 user_finfo = u64_to_user_ptr(info.func_info);
2463 ulen = min_t(u32, info.nr_func_info, ulen);
2464 if (copy_to_user(user_finfo, prog->aux->func_info,
2465 info.func_info_rec_size * ulen))
2466 return -EFAULT;
2467 }
2468
2469 ulen = info.nr_line_info;
2470 info.nr_line_info = prog->aux->nr_linfo;
2471 if (info.nr_line_info && ulen) {
2472 __u8 __user *user_linfo;
2473
2474 user_linfo = u64_to_user_ptr(info.line_info);
2475 ulen = min_t(u32, info.nr_line_info, ulen);
2476 if (copy_to_user(user_linfo, prog->aux->linfo,
2477 info.line_info_rec_size * ulen))
2478 return -EFAULT;
2479 }
2480
2481 ulen = info.nr_jited_line_info;
2482 if (prog->aux->jited_linfo)
2483 info.nr_jited_line_info = prog->aux->nr_linfo;
2484 else
2485 info.nr_jited_line_info = 0;
2486 if (info.nr_jited_line_info && ulen) {
2487 if (bpf_dump_raw_ok()) {
2488 __u64 __user *user_linfo;
2489 u32 i;
2490
2491 user_linfo = u64_to_user_ptr(info.jited_line_info);
2492 ulen = min_t(u32, info.nr_jited_line_info, ulen);
2493 for (i = 0; i < ulen; i++) {
2494 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
2495 &user_linfo[i]))
2496 return -EFAULT;
2497 }
2498 } else {
2499 info.jited_line_info = 0;
2500 }
2501 }
2502
2503 ulen = info.nr_prog_tags;
2504 info.nr_prog_tags = prog->aux->func_cnt ? : 1;
2505 if (ulen) {
2506 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
2507 u32 i;
2508
2509 user_prog_tags = u64_to_user_ptr(info.prog_tags);
2510 ulen = min_t(u32, info.nr_prog_tags, ulen);
2511 if (prog->aux->func_cnt) {
2512 for (i = 0; i < ulen; i++) {
2513 if (copy_to_user(user_prog_tags[i],
2514 prog->aux->func[i]->tag,
2515 BPF_TAG_SIZE))
2516 return -EFAULT;
2517 }
2518 } else {
2519 if (copy_to_user(user_prog_tags[0],
2520 prog->tag, BPF_TAG_SIZE))
2521 return -EFAULT;
2522 }
2523 }
2524
2525 done:
2526 if (copy_to_user(uinfo, &info, info_len) ||
2527 put_user(info_len, &uattr->info.info_len))
2528 return -EFAULT;
2529
2530 return 0;
2531 }
2532
2533 static int bpf_map_get_info_by_fd(struct bpf_map *map,
2534 const union bpf_attr *attr,
2535 union bpf_attr __user *uattr)
2536 {
2537 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2538 struct bpf_map_info info = {};
2539 u32 info_len = attr->info.info_len;
2540 int err;
2541
2542 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2543 if (err)
2544 return err;
2545 info_len = min_t(u32, sizeof(info), info_len);
2546
2547 info.type = map->map_type;
2548 info.id = map->id;
2549 info.key_size = map->key_size;
2550 info.value_size = map->value_size;
2551 info.max_entries = map->max_entries;
2552 info.map_flags = map->map_flags;
2553 memcpy(info.name, map->name, sizeof(map->name));
2554
2555 if (map->btf) {
2556 info.btf_id = btf_id(map->btf);
2557 info.btf_key_type_id = map->btf_key_type_id;
2558 info.btf_value_type_id = map->btf_value_type_id;
2559 }
2560
2561 if (bpf_map_is_dev_bound(map)) {
2562 err = bpf_map_offload_info_fill(&info, map);
2563 if (err)
2564 return err;
2565 }
2566
2567 if (copy_to_user(uinfo, &info, info_len) ||
2568 put_user(info_len, &uattr->info.info_len))
2569 return -EFAULT;
2570
2571 return 0;
2572 }
2573
2574 static int bpf_btf_get_info_by_fd(struct btf *btf,
2575 const union bpf_attr *attr,
2576 union bpf_attr __user *uattr)
2577 {
2578 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2579 u32 info_len = attr->info.info_len;
2580 int err;
2581
2582 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2583 if (err)
2584 return err;
2585
2586 return btf_get_info_by_fd(btf, attr, uattr);
2587 }
2588
2589 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2590
2591 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2592 union bpf_attr __user *uattr)
2593 {
2594 int ufd = attr->info.bpf_fd;
2595 struct fd f;
2596 int err;
2597
2598 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2599 return -EINVAL;
2600
2601 f = fdget(ufd);
2602 if (!f.file)
2603 return -EBADFD;
2604
2605 if (f.file->f_op == &bpf_prog_fops)
2606 err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
2607 uattr);
2608 else if (f.file->f_op == &bpf_map_fops)
2609 err = bpf_map_get_info_by_fd(f.file->private_data, attr,
2610 uattr);
2611 else if (f.file->f_op == &btf_fops)
2612 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
2613 else
2614 err = -EINVAL;
2615
2616 fdput(f);
2617 return err;
2618 }
2619
2620 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2621
2622 static int bpf_btf_load(const union bpf_attr *attr)
2623 {
2624 if (CHECK_ATTR(BPF_BTF_LOAD))
2625 return -EINVAL;
2626
2627 if (!capable(CAP_SYS_ADMIN))
2628 return -EPERM;
2629
2630 return btf_new_fd(attr);
2631 }
2632
2633 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2634
2635 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2636 {
2637 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2638 return -EINVAL;
2639
2640 if (!capable(CAP_SYS_ADMIN))
2641 return -EPERM;
2642
2643 return btf_get_fd_by_id(attr->btf_id);
2644 }
2645
2646 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2647 union bpf_attr __user *uattr,
2648 u32 prog_id, u32 fd_type,
2649 const char *buf, u64 probe_offset,
2650 u64 probe_addr)
2651 {
2652 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2653 u32 len = buf ? strlen(buf) : 0, input_len;
2654 int err = 0;
2655
2656 if (put_user(len, &uattr->task_fd_query.buf_len))
2657 return -EFAULT;
2658 input_len = attr->task_fd_query.buf_len;
2659 if (input_len && ubuf) {
2660 if (!len) {
2661 /* nothing to copy, just make ubuf NULL terminated */
2662 char zero = '\0';
2663
2664 if (put_user(zero, ubuf))
2665 return -EFAULT;
2666 } else if (input_len >= len + 1) {
2667 /* ubuf can hold the string with NULL terminator */
2668 if (copy_to_user(ubuf, buf, len + 1))
2669 return -EFAULT;
2670 } else {
2671 /* ubuf cannot hold the string with NULL terminator,
2672 * do a partial copy with NULL terminator.
2673 */
2674 char zero = '\0';
2675
2676 err = -ENOSPC;
2677 if (copy_to_user(ubuf, buf, input_len - 1))
2678 return -EFAULT;
2679 if (put_user(zero, ubuf + input_len - 1))
2680 return -EFAULT;
2681 }
2682 }
2683
2684 if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2685 put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2686 put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2687 put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2688 return -EFAULT;
2689
2690 return err;
2691 }
2692
2693 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2694
2695 static int bpf_task_fd_query(const union bpf_attr *attr,
2696 union bpf_attr __user *uattr)
2697 {
2698 pid_t pid = attr->task_fd_query.pid;
2699 u32 fd = attr->task_fd_query.fd;
2700 const struct perf_event *event;
2701 struct files_struct *files;
2702 struct task_struct *task;
2703 struct file *file;
2704 int err;
2705
2706 if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2707 return -EINVAL;
2708
2709 if (!capable(CAP_SYS_ADMIN))
2710 return -EPERM;
2711
2712 if (attr->task_fd_query.flags != 0)
2713 return -EINVAL;
2714
2715 task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2716 if (!task)
2717 return -ENOENT;
2718
2719 files = get_files_struct(task);
2720 put_task_struct(task);
2721 if (!files)
2722 return -ENOENT;
2723
2724 err = 0;
2725 spin_lock(&files->file_lock);
2726 file = fcheck_files(files, fd);
2727 if (!file)
2728 err = -EBADF;
2729 else
2730 get_file(file);
2731 spin_unlock(&files->file_lock);
2732 put_files_struct(files);
2733
2734 if (err)
2735 goto out;
2736
2737 if (file->f_op == &bpf_raw_tp_fops) {
2738 struct bpf_raw_tracepoint *raw_tp = file->private_data;
2739 struct bpf_raw_event_map *btp = raw_tp->btp;
2740
2741 err = bpf_task_fd_query_copy(attr, uattr,
2742 raw_tp->prog->aux->id,
2743 BPF_FD_TYPE_RAW_TRACEPOINT,
2744 btp->tp->name, 0, 0);
2745 goto put_file;
2746 }
2747
2748 event = perf_get_event(file);
2749 if (!IS_ERR(event)) {
2750 u64 probe_offset, probe_addr;
2751 u32 prog_id, fd_type;
2752 const char *buf;
2753
2754 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2755 &buf, &probe_offset,
2756 &probe_addr);
2757 if (!err)
2758 err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2759 fd_type, buf,
2760 probe_offset,
2761 probe_addr);
2762 goto put_file;
2763 }
2764
2765 err = -ENOTSUPP;
2766 put_file:
2767 fput(file);
2768 out:
2769 return err;
2770 }
2771
2772 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2773 {
2774 union bpf_attr attr = {};
2775 int err;
2776
2777 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2778 return -EPERM;
2779
2780 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2781 if (err)
2782 return err;
2783 size = min_t(u32, size, sizeof(attr));
2784
2785 /* copy attributes from user space, may be less than sizeof(bpf_attr) */
2786 if (copy_from_user(&attr, uattr, size) != 0)
2787 return -EFAULT;
2788
2789 err = security_bpf(cmd, &attr, size);
2790 if (err < 0)
2791 return err;
2792
2793 switch (cmd) {
2794 case BPF_MAP_CREATE:
2795 err = map_create(&attr);
2796 break;
2797 case BPF_MAP_LOOKUP_ELEM:
2798 err = map_lookup_elem(&attr);
2799 break;
2800 case BPF_MAP_UPDATE_ELEM:
2801 err = map_update_elem(&attr);
2802 break;
2803 case BPF_MAP_DELETE_ELEM:
2804 err = map_delete_elem(&attr);
2805 break;
2806 case BPF_MAP_GET_NEXT_KEY:
2807 err = map_get_next_key(&attr);
2808 break;
2809 case BPF_MAP_FREEZE:
2810 err = map_freeze(&attr);
2811 break;
2812 case BPF_PROG_LOAD:
2813 err = bpf_prog_load(&attr, uattr);
2814 break;
2815 case BPF_OBJ_PIN:
2816 err = bpf_obj_pin(&attr);
2817 break;
2818 case BPF_OBJ_GET:
2819 err = bpf_obj_get(&attr);
2820 break;
2821 case BPF_PROG_ATTACH:
2822 err = bpf_prog_attach(&attr);
2823 break;
2824 case BPF_PROG_DETACH:
2825 err = bpf_prog_detach(&attr);
2826 break;
2827 case BPF_PROG_QUERY:
2828 err = bpf_prog_query(&attr, uattr);
2829 break;
2830 case BPF_PROG_TEST_RUN:
2831 err = bpf_prog_test_run(&attr, uattr);
2832 break;
2833 case BPF_PROG_GET_NEXT_ID:
2834 err = bpf_obj_get_next_id(&attr, uattr,
2835 &prog_idr, &prog_idr_lock);
2836 break;
2837 case BPF_MAP_GET_NEXT_ID:
2838 err = bpf_obj_get_next_id(&attr, uattr,
2839 &map_idr, &map_idr_lock);
2840 break;
2841 case BPF_PROG_GET_FD_BY_ID:
2842 err = bpf_prog_get_fd_by_id(&attr);
2843 break;
2844 case BPF_MAP_GET_FD_BY_ID:
2845 err = bpf_map_get_fd_by_id(&attr);
2846 break;
2847 case BPF_OBJ_GET_INFO_BY_FD:
2848 err = bpf_obj_get_info_by_fd(&attr, uattr);
2849 break;
2850 case BPF_RAW_TRACEPOINT_OPEN:
2851 err = bpf_raw_tracepoint_open(&attr);
2852 break;
2853 case BPF_BTF_LOAD:
2854 err = bpf_btf_load(&attr);
2855 break;
2856 case BPF_BTF_GET_FD_BY_ID:
2857 err = bpf_btf_get_fd_by_id(&attr);
2858 break;
2859 case BPF_TASK_FD_QUERY:
2860 err = bpf_task_fd_query(&attr, uattr);
2861 break;
2862 case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2863 err = map_lookup_and_delete_elem(&attr);
2864 break;
2865 default:
2866 err = -EINVAL;
2867 break;
2868 }
2869
2870 return err;
2871 }
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