syscall.c 55 KB

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  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/btf.h>
  34. #include <linux/nospec.h>
  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. #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
  42. DEFINE_PER_CPU(int, bpf_prog_active);
  43. static DEFINE_IDR(prog_idr);
  44. static DEFINE_SPINLOCK(prog_idr_lock);
  45. static DEFINE_IDR(map_idr);
  46. static DEFINE_SPINLOCK(map_idr_lock);
  47. int sysctl_unprivileged_bpf_disabled __read_mostly;
  48. static const struct bpf_map_ops * const bpf_map_types[] = {
  49. #define BPF_PROG_TYPE(_id, _ops)
  50. #define BPF_MAP_TYPE(_id, _ops) \
  51. [_id] = &_ops,
  52. #include <linux/bpf_types.h>
  53. #undef BPF_PROG_TYPE
  54. #undef BPF_MAP_TYPE
  55. };
  56. /*
  57. * If we're handed a bigger struct than we know of, ensure all the unknown bits
  58. * are 0 - i.e. new user-space does not rely on any kernel feature extensions
  59. * we don't know about yet.
  60. *
  61. * There is a ToCToU between this function call and the following
  62. * copy_from_user() call. However, this is not a concern since this function is
  63. * meant to be a future-proofing of bits.
  64. */
  65. int bpf_check_uarg_tail_zero(void __user *uaddr,
  66. size_t expected_size,
  67. size_t actual_size)
  68. {
  69. unsigned char __user *addr;
  70. unsigned char __user *end;
  71. unsigned char val;
  72. int err;
  73. if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
  74. return -E2BIG;
  75. if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size)))
  76. return -EFAULT;
  77. if (actual_size <= expected_size)
  78. return 0;
  79. addr = uaddr + expected_size;
  80. end = uaddr + actual_size;
  81. for (; addr < end; addr++) {
  82. err = get_user(val, addr);
  83. if (err)
  84. return err;
  85. if (val)
  86. return -E2BIG;
  87. }
  88. return 0;
  89. }
  90. const struct bpf_map_ops bpf_map_offload_ops = {
  91. .map_alloc = bpf_map_offload_map_alloc,
  92. .map_free = bpf_map_offload_map_free,
  93. };
  94. static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
  95. {
  96. const struct bpf_map_ops *ops;
  97. u32 type = attr->map_type;
  98. struct bpf_map *map;
  99. int err;
  100. if (type >= ARRAY_SIZE(bpf_map_types))
  101. return ERR_PTR(-EINVAL);
  102. type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
  103. ops = bpf_map_types[type];
  104. if (!ops)
  105. return ERR_PTR(-EINVAL);
  106. if (ops->map_alloc_check) {
  107. err = ops->map_alloc_check(attr);
  108. if (err)
  109. return ERR_PTR(err);
  110. }
  111. if (attr->map_ifindex)
  112. ops = &bpf_map_offload_ops;
  113. map = ops->map_alloc(attr);
  114. if (IS_ERR(map))
  115. return map;
  116. map->ops = ops;
  117. map->map_type = type;
  118. return map;
  119. }
  120. void *bpf_map_area_alloc(size_t size, int numa_node)
  121. {
  122. /* We definitely need __GFP_NORETRY, so OOM killer doesn't
  123. * trigger under memory pressure as we really just want to
  124. * fail instead.
  125. */
  126. const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
  127. void *area;
  128. if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
  129. area = kmalloc_node(size, GFP_USER | flags, numa_node);
  130. if (area != NULL)
  131. return area;
  132. }
  133. return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags,
  134. __builtin_return_address(0));
  135. }
  136. void bpf_map_area_free(void *area)
  137. {
  138. kvfree(area);
  139. }
  140. void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
  141. {
  142. map->map_type = attr->map_type;
  143. map->key_size = attr->key_size;
  144. map->value_size = attr->value_size;
  145. map->max_entries = attr->max_entries;
  146. map->map_flags = attr->map_flags;
  147. map->numa_node = bpf_map_attr_numa_node(attr);
  148. }
  149. int bpf_map_precharge_memlock(u32 pages)
  150. {
  151. struct user_struct *user = get_current_user();
  152. unsigned long memlock_limit, cur;
  153. memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
  154. cur = atomic_long_read(&user->locked_vm);
  155. free_uid(user);
  156. if (cur + pages > memlock_limit)
  157. return -EPERM;
  158. return 0;
  159. }
  160. static int bpf_charge_memlock(struct user_struct *user, u32 pages)
  161. {
  162. unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
  163. if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
  164. atomic_long_sub(pages, &user->locked_vm);
  165. return -EPERM;
  166. }
  167. return 0;
  168. }
  169. static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
  170. {
  171. atomic_long_sub(pages, &user->locked_vm);
  172. }
  173. static int bpf_map_init_memlock(struct bpf_map *map)
  174. {
  175. struct user_struct *user = get_current_user();
  176. int ret;
  177. ret = bpf_charge_memlock(user, map->pages);
  178. if (ret) {
  179. free_uid(user);
  180. return ret;
  181. }
  182. map->user = user;
  183. return ret;
  184. }
  185. static void bpf_map_release_memlock(struct bpf_map *map)
  186. {
  187. struct user_struct *user = map->user;
  188. bpf_uncharge_memlock(user, map->pages);
  189. free_uid(user);
  190. }
  191. int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
  192. {
  193. int ret;
  194. ret = bpf_charge_memlock(map->user, pages);
  195. if (ret)
  196. return ret;
  197. map->pages += pages;
  198. return ret;
  199. }
  200. void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
  201. {
  202. bpf_uncharge_memlock(map->user, pages);
  203. map->pages -= pages;
  204. }
  205. static int bpf_map_alloc_id(struct bpf_map *map)
  206. {
  207. int id;
  208. idr_preload(GFP_KERNEL);
  209. spin_lock_bh(&map_idr_lock);
  210. id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
  211. if (id > 0)
  212. map->id = id;
  213. spin_unlock_bh(&map_idr_lock);
  214. idr_preload_end();
  215. if (WARN_ON_ONCE(!id))
  216. return -ENOSPC;
  217. return id > 0 ? 0 : id;
  218. }
  219. void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
  220. {
  221. unsigned long flags;
  222. /* Offloaded maps are removed from the IDR store when their device
  223. * disappears - even if someone holds an fd to them they are unusable,
  224. * the memory is gone, all ops will fail; they are simply waiting for
  225. * refcnt to drop to be freed.
  226. */
  227. if (!map->id)
  228. return;
  229. if (do_idr_lock)
  230. spin_lock_irqsave(&map_idr_lock, flags);
  231. else
  232. __acquire(&map_idr_lock);
  233. idr_remove(&map_idr, map->id);
  234. map->id = 0;
  235. if (do_idr_lock)
  236. spin_unlock_irqrestore(&map_idr_lock, flags);
  237. else
  238. __release(&map_idr_lock);
  239. }
  240. /* called from workqueue */
  241. static void bpf_map_free_deferred(struct work_struct *work)
  242. {
  243. struct bpf_map *map = container_of(work, struct bpf_map, work);
  244. bpf_map_release_memlock(map);
  245. security_bpf_map_free(map);
  246. /* implementation dependent freeing */
  247. map->ops->map_free(map);
  248. }
  249. static void bpf_map_put_uref(struct bpf_map *map)
  250. {
  251. if (atomic_dec_and_test(&map->usercnt)) {
  252. if (map->ops->map_release_uref)
  253. map->ops->map_release_uref(map);
  254. }
  255. }
  256. /* decrement map refcnt and schedule it for freeing via workqueue
  257. * (unrelying map implementation ops->map_free() might sleep)
  258. */
  259. static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
  260. {
  261. if (atomic_dec_and_test(&map->refcnt)) {
  262. /* bpf_map_free_id() must be called first */
  263. bpf_map_free_id(map, do_idr_lock);
  264. btf_put(map->btf);
  265. INIT_WORK(&map->work, bpf_map_free_deferred);
  266. schedule_work(&map->work);
  267. }
  268. }
  269. void bpf_map_put(struct bpf_map *map)
  270. {
  271. __bpf_map_put(map, true);
  272. }
  273. EXPORT_SYMBOL_GPL(bpf_map_put);
  274. void bpf_map_put_with_uref(struct bpf_map *map)
  275. {
  276. bpf_map_put_uref(map);
  277. bpf_map_put(map);
  278. }
  279. static int bpf_map_release(struct inode *inode, struct file *filp)
  280. {
  281. struct bpf_map *map = filp->private_data;
  282. if (map->ops->map_release)
  283. map->ops->map_release(map, filp);
  284. bpf_map_put_with_uref(map);
  285. return 0;
  286. }
  287. #ifdef CONFIG_PROC_FS
  288. static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
  289. {
  290. const struct bpf_map *map = filp->private_data;
  291. const struct bpf_array *array;
  292. u32 owner_prog_type = 0;
  293. u32 owner_jited = 0;
  294. if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
  295. array = container_of(map, struct bpf_array, map);
  296. owner_prog_type = array->owner_prog_type;
  297. owner_jited = array->owner_jited;
  298. }
  299. seq_printf(m,
  300. "map_type:\t%u\n"
  301. "key_size:\t%u\n"
  302. "value_size:\t%u\n"
  303. "max_entries:\t%u\n"
  304. "map_flags:\t%#x\n"
  305. "memlock:\t%llu\n"
  306. "map_id:\t%u\n",
  307. map->map_type,
  308. map->key_size,
  309. map->value_size,
  310. map->max_entries,
  311. map->map_flags,
  312. map->pages * 1ULL << PAGE_SHIFT,
  313. map->id);
  314. if (owner_prog_type) {
  315. seq_printf(m, "owner_prog_type:\t%u\n",
  316. owner_prog_type);
  317. seq_printf(m, "owner_jited:\t%u\n",
  318. owner_jited);
  319. }
  320. }
  321. #endif
  322. static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
  323. loff_t *ppos)
  324. {
  325. /* We need this handler such that alloc_file() enables
  326. * f_mode with FMODE_CAN_READ.
  327. */
  328. return -EINVAL;
  329. }
  330. static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
  331. size_t siz, loff_t *ppos)
  332. {
  333. /* We need this handler such that alloc_file() enables
  334. * f_mode with FMODE_CAN_WRITE.
  335. */
  336. return -EINVAL;
  337. }
  338. const struct file_operations bpf_map_fops = {
  339. #ifdef CONFIG_PROC_FS
  340. .show_fdinfo = bpf_map_show_fdinfo,
  341. #endif
  342. .release = bpf_map_release,
  343. .read = bpf_dummy_read,
  344. .write = bpf_dummy_write,
  345. };
  346. int bpf_map_new_fd(struct bpf_map *map, int flags)
  347. {
  348. int ret;
  349. ret = security_bpf_map(map, OPEN_FMODE(flags));
  350. if (ret < 0)
  351. return ret;
  352. return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
  353. flags | O_CLOEXEC);
  354. }
  355. int bpf_get_file_flag(int flags)
  356. {
  357. if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
  358. return -EINVAL;
  359. if (flags & BPF_F_RDONLY)
  360. return O_RDONLY;
  361. if (flags & BPF_F_WRONLY)
  362. return O_WRONLY;
  363. return O_RDWR;
  364. }
  365. /* helper macro to check that unused fields 'union bpf_attr' are zero */
  366. #define CHECK_ATTR(CMD) \
  367. memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
  368. sizeof(attr->CMD##_LAST_FIELD), 0, \
  369. sizeof(*attr) - \
  370. offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
  371. sizeof(attr->CMD##_LAST_FIELD)) != NULL
  372. /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
  373. * Return 0 on success and < 0 on error.
  374. */
  375. static int bpf_obj_name_cpy(char *dst, const char *src)
  376. {
  377. const char *end = src + BPF_OBJ_NAME_LEN;
  378. memset(dst, 0, BPF_OBJ_NAME_LEN);
  379. /* Copy all isalnum() and '_' char */
  380. while (src < end && *src) {
  381. if (!isalnum(*src) && *src != '_')
  382. return -EINVAL;
  383. *dst++ = *src++;
  384. }
  385. /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
  386. if (src == end)
  387. return -EINVAL;
  388. return 0;
  389. }
  390. #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
  391. /* called via syscall */
  392. static int map_create(union bpf_attr *attr)
  393. {
  394. int numa_node = bpf_map_attr_numa_node(attr);
  395. struct bpf_map *map;
  396. int f_flags;
  397. int err;
  398. err = CHECK_ATTR(BPF_MAP_CREATE);
  399. if (err)
  400. return -EINVAL;
  401. f_flags = bpf_get_file_flag(attr->map_flags);
  402. if (f_flags < 0)
  403. return f_flags;
  404. if (numa_node != NUMA_NO_NODE &&
  405. ((unsigned int)numa_node >= nr_node_ids ||
  406. !node_online(numa_node)))
  407. return -EINVAL;
  408. /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
  409. map = find_and_alloc_map(attr);
  410. if (IS_ERR(map))
  411. return PTR_ERR(map);
  412. err = bpf_obj_name_cpy(map->name, attr->map_name);
  413. if (err)
  414. goto free_map_nouncharge;
  415. atomic_set(&map->refcnt, 1);
  416. atomic_set(&map->usercnt, 1);
  417. if (bpf_map_support_seq_show(map) &&
  418. (attr->btf_key_type_id || attr->btf_value_type_id)) {
  419. struct btf *btf;
  420. if (!attr->btf_key_type_id || !attr->btf_value_type_id) {
  421. err = -EINVAL;
  422. goto free_map_nouncharge;
  423. }
  424. btf = btf_get_by_fd(attr->btf_fd);
  425. if (IS_ERR(btf)) {
  426. err = PTR_ERR(btf);
  427. goto free_map_nouncharge;
  428. }
  429. err = map->ops->map_check_btf(map, btf, attr->btf_key_type_id,
  430. attr->btf_value_type_id);
  431. if (err) {
  432. btf_put(btf);
  433. goto free_map_nouncharge;
  434. }
  435. map->btf = btf;
  436. map->btf_key_type_id = attr->btf_key_type_id;
  437. map->btf_value_type_id = attr->btf_value_type_id;
  438. }
  439. err = security_bpf_map_alloc(map);
  440. if (err)
  441. goto free_map_nouncharge;
  442. err = bpf_map_init_memlock(map);
  443. if (err)
  444. goto free_map_sec;
  445. err = bpf_map_alloc_id(map);
  446. if (err)
  447. goto free_map;
  448. err = bpf_map_new_fd(map, f_flags);
  449. if (err < 0) {
  450. /* failed to allocate fd.
  451. * bpf_map_put() is needed because the above
  452. * bpf_map_alloc_id() has published the map
  453. * to the userspace and the userspace may
  454. * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
  455. */
  456. bpf_map_put(map);
  457. return err;
  458. }
  459. return err;
  460. free_map:
  461. bpf_map_release_memlock(map);
  462. free_map_sec:
  463. security_bpf_map_free(map);
  464. free_map_nouncharge:
  465. btf_put(map->btf);
  466. map->ops->map_free(map);
  467. return err;
  468. }
  469. /* if error is returned, fd is released.
  470. * On success caller should complete fd access with matching fdput()
  471. */
  472. struct bpf_map *__bpf_map_get(struct fd f)
  473. {
  474. if (!f.file)
  475. return ERR_PTR(-EBADF);
  476. if (f.file->f_op != &bpf_map_fops) {
  477. fdput(f);
  478. return ERR_PTR(-EINVAL);
  479. }
  480. return f.file->private_data;
  481. }
  482. /* prog's and map's refcnt limit */
  483. #define BPF_MAX_REFCNT 32768
  484. struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
  485. {
  486. if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
  487. atomic_dec(&map->refcnt);
  488. return ERR_PTR(-EBUSY);
  489. }
  490. if (uref)
  491. atomic_inc(&map->usercnt);
  492. return map;
  493. }
  494. EXPORT_SYMBOL_GPL(bpf_map_inc);
  495. struct bpf_map *bpf_map_get_with_uref(u32 ufd)
  496. {
  497. struct fd f = fdget(ufd);
  498. struct bpf_map *map;
  499. map = __bpf_map_get(f);
  500. if (IS_ERR(map))
  501. return map;
  502. map = bpf_map_inc(map, true);
  503. fdput(f);
  504. return map;
  505. }
  506. /* map_idr_lock should have been held */
  507. static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
  508. bool uref)
  509. {
  510. int refold;
  511. refold = __atomic_add_unless(&map->refcnt, 1, 0);
  512. if (refold >= BPF_MAX_REFCNT) {
  513. __bpf_map_put(map, false);
  514. return ERR_PTR(-EBUSY);
  515. }
  516. if (!refold)
  517. return ERR_PTR(-ENOENT);
  518. if (uref)
  519. atomic_inc(&map->usercnt);
  520. return map;
  521. }
  522. int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
  523. {
  524. return -ENOTSUPP;
  525. }
  526. /* last field in 'union bpf_attr' used by this command */
  527. #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
  528. static int map_lookup_elem(union bpf_attr *attr)
  529. {
  530. void __user *ukey = u64_to_user_ptr(attr->key);
  531. void __user *uvalue = u64_to_user_ptr(attr->value);
  532. int ufd = attr->map_fd;
  533. struct bpf_map *map;
  534. void *key, *value, *ptr;
  535. u32 value_size;
  536. struct fd f;
  537. int err;
  538. if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
  539. return -EINVAL;
  540. f = fdget(ufd);
  541. map = __bpf_map_get(f);
  542. if (IS_ERR(map))
  543. return PTR_ERR(map);
  544. if (!(f.file->f_mode & FMODE_CAN_READ)) {
  545. err = -EPERM;
  546. goto err_put;
  547. }
  548. key = memdup_user(ukey, map->key_size);
  549. if (IS_ERR(key)) {
  550. err = PTR_ERR(key);
  551. goto err_put;
  552. }
  553. if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  554. map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
  555. map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
  556. value_size = round_up(map->value_size, 8) * num_possible_cpus();
  557. else if (IS_FD_MAP(map))
  558. value_size = sizeof(u32);
  559. else
  560. value_size = map->value_size;
  561. err = -ENOMEM;
  562. value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
  563. if (!value)
  564. goto free_key;
  565. if (bpf_map_is_dev_bound(map)) {
  566. err = bpf_map_offload_lookup_elem(map, key, value);
  567. } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  568. map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
  569. err = bpf_percpu_hash_copy(map, key, value);
  570. } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
  571. err = bpf_percpu_array_copy(map, key, value);
  572. } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
  573. err = bpf_stackmap_copy(map, key, value);
  574. } else if (IS_FD_ARRAY(map)) {
  575. err = bpf_fd_array_map_lookup_elem(map, key, value);
  576. } else if (IS_FD_HASH(map)) {
  577. err = bpf_fd_htab_map_lookup_elem(map, key, value);
  578. } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
  579. err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
  580. } else {
  581. rcu_read_lock();
  582. ptr = map->ops->map_lookup_elem(map, key);
  583. if (ptr)
  584. memcpy(value, ptr, value_size);
  585. rcu_read_unlock();
  586. err = ptr ? 0 : -ENOENT;
  587. }
  588. if (err)
  589. goto free_value;
  590. err = -EFAULT;
  591. if (copy_to_user(uvalue, value, value_size) != 0)
  592. goto free_value;
  593. err = 0;
  594. free_value:
  595. kfree(value);
  596. free_key:
  597. kfree(key);
  598. err_put:
  599. fdput(f);
  600. return err;
  601. }
  602. #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
  603. static int map_update_elem(union bpf_attr *attr)
  604. {
  605. void __user *ukey = u64_to_user_ptr(attr->key);
  606. void __user *uvalue = u64_to_user_ptr(attr->value);
  607. int ufd = attr->map_fd;
  608. struct bpf_map *map;
  609. void *key, *value;
  610. u32 value_size;
  611. struct fd f;
  612. int err;
  613. if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
  614. return -EINVAL;
  615. f = fdget(ufd);
  616. map = __bpf_map_get(f);
  617. if (IS_ERR(map))
  618. return PTR_ERR(map);
  619. if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
  620. err = -EPERM;
  621. goto err_put;
  622. }
  623. key = memdup_user(ukey, map->key_size);
  624. if (IS_ERR(key)) {
  625. err = PTR_ERR(key);
  626. goto err_put;
  627. }
  628. if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  629. map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
  630. map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
  631. value_size = round_up(map->value_size, 8) * num_possible_cpus();
  632. else
  633. value_size = map->value_size;
  634. err = -ENOMEM;
  635. value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
  636. if (!value)
  637. goto free_key;
  638. err = -EFAULT;
  639. if (copy_from_user(value, uvalue, value_size) != 0)
  640. goto free_value;
  641. /* Need to create a kthread, thus must support schedule */
  642. if (bpf_map_is_dev_bound(map)) {
  643. err = bpf_map_offload_update_elem(map, key, value, attr->flags);
  644. goto out;
  645. } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
  646. map->map_type == BPF_MAP_TYPE_SOCKHASH ||
  647. map->map_type == BPF_MAP_TYPE_SOCKMAP) {
  648. err = map->ops->map_update_elem(map, key, value, attr->flags);
  649. goto out;
  650. }
  651. /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
  652. * inside bpf map update or delete otherwise deadlocks are possible
  653. */
  654. preempt_disable();
  655. __this_cpu_inc(bpf_prog_active);
  656. if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  657. map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
  658. err = bpf_percpu_hash_update(map, key, value, attr->flags);
  659. } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
  660. err = bpf_percpu_array_update(map, key, value, attr->flags);
  661. } else if (IS_FD_ARRAY(map)) {
  662. rcu_read_lock();
  663. err = bpf_fd_array_map_update_elem(map, f.file, key, value,
  664. attr->flags);
  665. rcu_read_unlock();
  666. } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
  667. rcu_read_lock();
  668. err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
  669. attr->flags);
  670. rcu_read_unlock();
  671. } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
  672. /* rcu_read_lock() is not needed */
  673. err = bpf_fd_reuseport_array_update_elem(map, key, value,
  674. attr->flags);
  675. } else {
  676. rcu_read_lock();
  677. err = map->ops->map_update_elem(map, key, value, attr->flags);
  678. rcu_read_unlock();
  679. }
  680. __this_cpu_dec(bpf_prog_active);
  681. preempt_enable();
  682. out:
  683. free_value:
  684. kfree(value);
  685. free_key:
  686. kfree(key);
  687. err_put:
  688. fdput(f);
  689. return err;
  690. }
  691. #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
  692. static int map_delete_elem(union bpf_attr *attr)
  693. {
  694. void __user *ukey = u64_to_user_ptr(attr->key);
  695. int ufd = attr->map_fd;
  696. struct bpf_map *map;
  697. struct fd f;
  698. void *key;
  699. int err;
  700. if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
  701. return -EINVAL;
  702. f = fdget(ufd);
  703. map = __bpf_map_get(f);
  704. if (IS_ERR(map))
  705. return PTR_ERR(map);
  706. if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
  707. err = -EPERM;
  708. goto err_put;
  709. }
  710. key = memdup_user(ukey, map->key_size);
  711. if (IS_ERR(key)) {
  712. err = PTR_ERR(key);
  713. goto err_put;
  714. }
  715. if (bpf_map_is_dev_bound(map)) {
  716. err = bpf_map_offload_delete_elem(map, key);
  717. goto out;
  718. }
  719. preempt_disable();
  720. __this_cpu_inc(bpf_prog_active);
  721. rcu_read_lock();
  722. err = map->ops->map_delete_elem(map, key);
  723. rcu_read_unlock();
  724. __this_cpu_dec(bpf_prog_active);
  725. preempt_enable();
  726. out:
  727. kfree(key);
  728. err_put:
  729. fdput(f);
  730. return err;
  731. }
  732. /* last field in 'union bpf_attr' used by this command */
  733. #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
  734. static int map_get_next_key(union bpf_attr *attr)
  735. {
  736. void __user *ukey = u64_to_user_ptr(attr->key);
  737. void __user *unext_key = u64_to_user_ptr(attr->next_key);
  738. int ufd = attr->map_fd;
  739. struct bpf_map *map;
  740. void *key, *next_key;
  741. struct fd f;
  742. int err;
  743. if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
  744. return -EINVAL;
  745. f = fdget(ufd);
  746. map = __bpf_map_get(f);
  747. if (IS_ERR(map))
  748. return PTR_ERR(map);
  749. if (!(f.file->f_mode & FMODE_CAN_READ)) {
  750. err = -EPERM;
  751. goto err_put;
  752. }
  753. if (ukey) {
  754. key = memdup_user(ukey, map->key_size);
  755. if (IS_ERR(key)) {
  756. err = PTR_ERR(key);
  757. goto err_put;
  758. }
  759. } else {
  760. key = NULL;
  761. }
  762. err = -ENOMEM;
  763. next_key = kmalloc(map->key_size, GFP_USER);
  764. if (!next_key)
  765. goto free_key;
  766. if (bpf_map_is_dev_bound(map)) {
  767. err = bpf_map_offload_get_next_key(map, key, next_key);
  768. goto out;
  769. }
  770. rcu_read_lock();
  771. err = map->ops->map_get_next_key(map, key, next_key);
  772. rcu_read_unlock();
  773. out:
  774. if (err)
  775. goto free_next_key;
  776. err = -EFAULT;
  777. if (copy_to_user(unext_key, next_key, map->key_size) != 0)
  778. goto free_next_key;
  779. err = 0;
  780. free_next_key:
  781. kfree(next_key);
  782. free_key:
  783. kfree(key);
  784. err_put:
  785. fdput(f);
  786. return err;
  787. }
  788. static const struct bpf_prog_ops * const bpf_prog_types[] = {
  789. #define BPF_PROG_TYPE(_id, _name) \
  790. [_id] = & _name ## _prog_ops,
  791. #define BPF_MAP_TYPE(_id, _ops)
  792. #include <linux/bpf_types.h>
  793. #undef BPF_PROG_TYPE
  794. #undef BPF_MAP_TYPE
  795. };
  796. static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
  797. {
  798. const struct bpf_prog_ops *ops;
  799. if (type >= ARRAY_SIZE(bpf_prog_types))
  800. return -EINVAL;
  801. type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
  802. ops = bpf_prog_types[type];
  803. if (!ops)
  804. return -EINVAL;
  805. if (!bpf_prog_is_dev_bound(prog->aux))
  806. prog->aux->ops = ops;
  807. else
  808. prog->aux->ops = &bpf_offload_prog_ops;
  809. prog->type = type;
  810. return 0;
  811. }
  812. /* drop refcnt on maps used by eBPF program and free auxilary data */
  813. static void free_used_maps(struct bpf_prog_aux *aux)
  814. {
  815. int i;
  816. if (aux->cgroup_storage)
  817. bpf_cgroup_storage_release(aux->prog, aux->cgroup_storage);
  818. for (i = 0; i < aux->used_map_cnt; i++)
  819. bpf_map_put(aux->used_maps[i]);
  820. kfree(aux->used_maps);
  821. }
  822. int __bpf_prog_charge(struct user_struct *user, u32 pages)
  823. {
  824. unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
  825. unsigned long user_bufs;
  826. if (user) {
  827. user_bufs = atomic_long_add_return(pages, &user->locked_vm);
  828. if (user_bufs > memlock_limit) {
  829. atomic_long_sub(pages, &user->locked_vm);
  830. return -EPERM;
  831. }
  832. }
  833. return 0;
  834. }
  835. void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
  836. {
  837. if (user)
  838. atomic_long_sub(pages, &user->locked_vm);
  839. }
  840. static int bpf_prog_charge_memlock(struct bpf_prog *prog)
  841. {
  842. struct user_struct *user = get_current_user();
  843. int ret;
  844. ret = __bpf_prog_charge(user, prog->pages);
  845. if (ret) {
  846. free_uid(user);
  847. return ret;
  848. }
  849. prog->aux->user = user;
  850. return 0;
  851. }
  852. static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
  853. {
  854. struct user_struct *user = prog->aux->user;
  855. __bpf_prog_uncharge(user, prog->pages);
  856. free_uid(user);
  857. }
  858. static int bpf_prog_alloc_id(struct bpf_prog *prog)
  859. {
  860. int id;
  861. idr_preload(GFP_KERNEL);
  862. spin_lock_bh(&prog_idr_lock);
  863. id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
  864. if (id > 0)
  865. prog->aux->id = id;
  866. spin_unlock_bh(&prog_idr_lock);
  867. idr_preload_end();
  868. /* id is in [1, INT_MAX) */
  869. if (WARN_ON_ONCE(!id))
  870. return -ENOSPC;
  871. return id > 0 ? 0 : id;
  872. }
  873. void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
  874. {
  875. /* cBPF to eBPF migrations are currently not in the idr store.
  876. * Offloaded programs are removed from the store when their device
  877. * disappears - even if someone grabs an fd to them they are unusable,
  878. * simply waiting for refcnt to drop to be freed.
  879. */
  880. if (!prog->aux->id)
  881. return;
  882. if (do_idr_lock)
  883. spin_lock_bh(&prog_idr_lock);
  884. else
  885. __acquire(&prog_idr_lock);
  886. idr_remove(&prog_idr, prog->aux->id);
  887. prog->aux->id = 0;
  888. if (do_idr_lock)
  889. spin_unlock_bh(&prog_idr_lock);
  890. else
  891. __release(&prog_idr_lock);
  892. }
  893. static void __bpf_prog_put_rcu(struct rcu_head *rcu)
  894. {
  895. struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
  896. free_used_maps(aux);
  897. bpf_prog_uncharge_memlock(aux->prog);
  898. security_bpf_prog_free(aux);
  899. bpf_prog_free(aux->prog);
  900. }
  901. static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
  902. {
  903. if (atomic_dec_and_test(&prog->aux->refcnt)) {
  904. /* bpf_prog_free_id() must be called first */
  905. bpf_prog_free_id(prog, do_idr_lock);
  906. bpf_prog_kallsyms_del_all(prog);
  907. call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
  908. }
  909. }
  910. void bpf_prog_put(struct bpf_prog *prog)
  911. {
  912. __bpf_prog_put(prog, true);
  913. }
  914. EXPORT_SYMBOL_GPL(bpf_prog_put);
  915. static int bpf_prog_release(struct inode *inode, struct file *filp)
  916. {
  917. struct bpf_prog *prog = filp->private_data;
  918. bpf_prog_put(prog);
  919. return 0;
  920. }
  921. #ifdef CONFIG_PROC_FS
  922. static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
  923. {
  924. const struct bpf_prog *prog = filp->private_data;
  925. char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
  926. bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
  927. seq_printf(m,
  928. "prog_type:\t%u\n"
  929. "prog_jited:\t%u\n"
  930. "prog_tag:\t%s\n"
  931. "memlock:\t%llu\n"
  932. "prog_id:\t%u\n",
  933. prog->type,
  934. prog->jited,
  935. prog_tag,
  936. prog->pages * 1ULL << PAGE_SHIFT,
  937. prog->aux->id);
  938. }
  939. #endif
  940. const struct file_operations bpf_prog_fops = {
  941. #ifdef CONFIG_PROC_FS
  942. .show_fdinfo = bpf_prog_show_fdinfo,
  943. #endif
  944. .release = bpf_prog_release,
  945. .read = bpf_dummy_read,
  946. .write = bpf_dummy_write,
  947. };
  948. int bpf_prog_new_fd(struct bpf_prog *prog)
  949. {
  950. int ret;
  951. ret = security_bpf_prog(prog);
  952. if (ret < 0)
  953. return ret;
  954. return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
  955. O_RDWR | O_CLOEXEC);
  956. }
  957. static struct bpf_prog *____bpf_prog_get(struct fd f)
  958. {
  959. if (!f.file)
  960. return ERR_PTR(-EBADF);
  961. if (f.file->f_op != &bpf_prog_fops) {
  962. fdput(f);
  963. return ERR_PTR(-EINVAL);
  964. }
  965. return f.file->private_data;
  966. }
  967. struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
  968. {
  969. if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
  970. atomic_sub(i, &prog->aux->refcnt);
  971. return ERR_PTR(-EBUSY);
  972. }
  973. return prog;
  974. }
  975. EXPORT_SYMBOL_GPL(bpf_prog_add);
  976. void bpf_prog_sub(struct bpf_prog *prog, int i)
  977. {
  978. /* Only to be used for undoing previous bpf_prog_add() in some
  979. * error path. We still know that another entity in our call
  980. * path holds a reference to the program, thus atomic_sub() can
  981. * be safely used in such cases!
  982. */
  983. WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
  984. }
  985. EXPORT_SYMBOL_GPL(bpf_prog_sub);
  986. struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
  987. {
  988. return bpf_prog_add(prog, 1);
  989. }
  990. EXPORT_SYMBOL_GPL(bpf_prog_inc);
  991. /* prog_idr_lock should have been held */
  992. struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
  993. {
  994. int refold;
  995. refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0);
  996. if (refold >= BPF_MAX_REFCNT) {
  997. __bpf_prog_put(prog, false);
  998. return ERR_PTR(-EBUSY);
  999. }
  1000. if (!refold)
  1001. return ERR_PTR(-ENOENT);
  1002. return prog;
  1003. }
  1004. EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
  1005. bool bpf_prog_get_ok(struct bpf_prog *prog,
  1006. enum bpf_prog_type *attach_type, bool attach_drv)
  1007. {
  1008. /* not an attachment, just a refcount inc, always allow */
  1009. if (!attach_type)
  1010. return true;
  1011. if (prog->type != *attach_type)
  1012. return false;
  1013. if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
  1014. return false;
  1015. return true;
  1016. }
  1017. static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
  1018. bool attach_drv)
  1019. {
  1020. struct fd f = fdget(ufd);
  1021. struct bpf_prog *prog;
  1022. prog = ____bpf_prog_get(f);
  1023. if (IS_ERR(prog))
  1024. return prog;
  1025. if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
  1026. prog = ERR_PTR(-EINVAL);
  1027. goto out;
  1028. }
  1029. prog = bpf_prog_inc(prog);
  1030. out:
  1031. fdput(f);
  1032. return prog;
  1033. }
  1034. struct bpf_prog *bpf_prog_get(u32 ufd)
  1035. {
  1036. return __bpf_prog_get(ufd, NULL, false);
  1037. }
  1038. struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
  1039. bool attach_drv)
  1040. {
  1041. return __bpf_prog_get(ufd, &type, attach_drv);
  1042. }
  1043. EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
  1044. /* Initially all BPF programs could be loaded w/o specifying
  1045. * expected_attach_type. Later for some of them specifying expected_attach_type
  1046. * at load time became required so that program could be validated properly.
  1047. * Programs of types that are allowed to be loaded both w/ and w/o (for
  1048. * backward compatibility) expected_attach_type, should have the default attach
  1049. * type assigned to expected_attach_type for the latter case, so that it can be
  1050. * validated later at attach time.
  1051. *
  1052. * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
  1053. * prog type requires it but has some attach types that have to be backward
  1054. * compatible.
  1055. */
  1056. static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
  1057. {
  1058. switch (attr->prog_type) {
  1059. case BPF_PROG_TYPE_CGROUP_SOCK:
  1060. /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
  1061. * exist so checking for non-zero is the way to go here.
  1062. */
  1063. if (!attr->expected_attach_type)
  1064. attr->expected_attach_type =
  1065. BPF_CGROUP_INET_SOCK_CREATE;
  1066. break;
  1067. }
  1068. }
  1069. static int
  1070. bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
  1071. enum bpf_attach_type expected_attach_type)
  1072. {
  1073. switch (prog_type) {
  1074. case BPF_PROG_TYPE_CGROUP_SOCK:
  1075. switch (expected_attach_type) {
  1076. case BPF_CGROUP_INET_SOCK_CREATE:
  1077. case BPF_CGROUP_INET4_POST_BIND:
  1078. case BPF_CGROUP_INET6_POST_BIND:
  1079. return 0;
  1080. default:
  1081. return -EINVAL;
  1082. }
  1083. case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  1084. switch (expected_attach_type) {
  1085. case BPF_CGROUP_INET4_BIND:
  1086. case BPF_CGROUP_INET6_BIND:
  1087. case BPF_CGROUP_INET4_CONNECT:
  1088. case BPF_CGROUP_INET6_CONNECT:
  1089. case BPF_CGROUP_UDP4_SENDMSG:
  1090. case BPF_CGROUP_UDP6_SENDMSG:
  1091. return 0;
  1092. default:
  1093. return -EINVAL;
  1094. }
  1095. default:
  1096. return 0;
  1097. }
  1098. }
  1099. /* last field in 'union bpf_attr' used by this command */
  1100. #define BPF_PROG_LOAD_LAST_FIELD expected_attach_type
  1101. static int bpf_prog_load(union bpf_attr *attr)
  1102. {
  1103. enum bpf_prog_type type = attr->prog_type;
  1104. struct bpf_prog *prog;
  1105. int err;
  1106. char license[128];
  1107. bool is_gpl;
  1108. if (CHECK_ATTR(BPF_PROG_LOAD))
  1109. return -EINVAL;
  1110. if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT)
  1111. return -EINVAL;
  1112. /* copy eBPF program license from user space */
  1113. if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
  1114. sizeof(license) - 1) < 0)
  1115. return -EFAULT;
  1116. license[sizeof(license) - 1] = 0;
  1117. /* eBPF programs must be GPL compatible to use GPL-ed functions */
  1118. is_gpl = license_is_gpl_compatible(license);
  1119. if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS)
  1120. return -E2BIG;
  1121. if (type == BPF_PROG_TYPE_KPROBE &&
  1122. attr->kern_version != LINUX_VERSION_CODE)
  1123. return -EINVAL;
  1124. if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
  1125. type != BPF_PROG_TYPE_CGROUP_SKB &&
  1126. !capable(CAP_SYS_ADMIN))
  1127. return -EPERM;
  1128. bpf_prog_load_fixup_attach_type(attr);
  1129. if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
  1130. return -EINVAL;
  1131. /* plain bpf_prog allocation */
  1132. prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
  1133. if (!prog)
  1134. return -ENOMEM;
  1135. prog->expected_attach_type = attr->expected_attach_type;
  1136. prog->aux->offload_requested = !!attr->prog_ifindex;
  1137. err = security_bpf_prog_alloc(prog->aux);
  1138. if (err)
  1139. goto free_prog_nouncharge;
  1140. err = bpf_prog_charge_memlock(prog);
  1141. if (err)
  1142. goto free_prog_sec;
  1143. prog->len = attr->insn_cnt;
  1144. err = -EFAULT;
  1145. if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
  1146. bpf_prog_insn_size(prog)) != 0)
  1147. goto free_prog;
  1148. prog->orig_prog = NULL;
  1149. prog->jited = 0;
  1150. atomic_set(&prog->aux->refcnt, 1);
  1151. prog->gpl_compatible = is_gpl ? 1 : 0;
  1152. if (bpf_prog_is_dev_bound(prog->aux)) {
  1153. err = bpf_prog_offload_init(prog, attr);
  1154. if (err)
  1155. goto free_prog;
  1156. }
  1157. /* find program type: socket_filter vs tracing_filter */
  1158. err = find_prog_type(type, prog);
  1159. if (err < 0)
  1160. goto free_prog;
  1161. prog->aux->load_time = ktime_get_boot_ns();
  1162. err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
  1163. if (err)
  1164. goto free_prog;
  1165. /* run eBPF verifier */
  1166. err = bpf_check(&prog, attr);
  1167. if (err < 0)
  1168. goto free_used_maps;
  1169. prog = bpf_prog_select_runtime(prog, &err);
  1170. if (err < 0)
  1171. goto free_used_maps;
  1172. err = bpf_prog_alloc_id(prog);
  1173. if (err)
  1174. goto free_used_maps;
  1175. err = bpf_prog_new_fd(prog);
  1176. if (err < 0) {
  1177. /* failed to allocate fd.
  1178. * bpf_prog_put() is needed because the above
  1179. * bpf_prog_alloc_id() has published the prog
  1180. * to the userspace and the userspace may
  1181. * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
  1182. */
  1183. bpf_prog_put(prog);
  1184. return err;
  1185. }
  1186. bpf_prog_kallsyms_add(prog);
  1187. return err;
  1188. free_used_maps:
  1189. bpf_prog_kallsyms_del_subprogs(prog);
  1190. free_used_maps(prog->aux);
  1191. free_prog:
  1192. bpf_prog_uncharge_memlock(prog);
  1193. free_prog_sec:
  1194. security_bpf_prog_free(prog->aux);
  1195. free_prog_nouncharge:
  1196. bpf_prog_free(prog);
  1197. return err;
  1198. }
  1199. #define BPF_OBJ_LAST_FIELD file_flags
  1200. static int bpf_obj_pin(const union bpf_attr *attr)
  1201. {
  1202. if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
  1203. return -EINVAL;
  1204. return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
  1205. }
  1206. static int bpf_obj_get(const union bpf_attr *attr)
  1207. {
  1208. if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
  1209. attr->file_flags & ~BPF_OBJ_FLAG_MASK)
  1210. return -EINVAL;
  1211. return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
  1212. attr->file_flags);
  1213. }
  1214. struct bpf_raw_tracepoint {
  1215. struct bpf_raw_event_map *btp;
  1216. struct bpf_prog *prog;
  1217. };
  1218. static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
  1219. {
  1220. struct bpf_raw_tracepoint *raw_tp = filp->private_data;
  1221. if (raw_tp->prog) {
  1222. bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
  1223. bpf_prog_put(raw_tp->prog);
  1224. }
  1225. kfree(raw_tp);
  1226. return 0;
  1227. }
  1228. static const struct file_operations bpf_raw_tp_fops = {
  1229. .release = bpf_raw_tracepoint_release,
  1230. .read = bpf_dummy_read,
  1231. .write = bpf_dummy_write,
  1232. };
  1233. #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
  1234. static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
  1235. {
  1236. struct bpf_raw_tracepoint *raw_tp;
  1237. struct bpf_raw_event_map *btp;
  1238. struct bpf_prog *prog;
  1239. char tp_name[128];
  1240. int tp_fd, err;
  1241. if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
  1242. sizeof(tp_name) - 1) < 0)
  1243. return -EFAULT;
  1244. tp_name[sizeof(tp_name) - 1] = 0;
  1245. btp = bpf_find_raw_tracepoint(tp_name);
  1246. if (!btp)
  1247. return -ENOENT;
  1248. raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
  1249. if (!raw_tp)
  1250. return -ENOMEM;
  1251. raw_tp->btp = btp;
  1252. prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
  1253. BPF_PROG_TYPE_RAW_TRACEPOINT);
  1254. if (IS_ERR(prog)) {
  1255. err = PTR_ERR(prog);
  1256. goto out_free_tp;
  1257. }
  1258. err = bpf_probe_register(raw_tp->btp, prog);
  1259. if (err)
  1260. goto out_put_prog;
  1261. raw_tp->prog = prog;
  1262. tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
  1263. O_CLOEXEC);
  1264. if (tp_fd < 0) {
  1265. bpf_probe_unregister(raw_tp->btp, prog);
  1266. err = tp_fd;
  1267. goto out_put_prog;
  1268. }
  1269. return tp_fd;
  1270. out_put_prog:
  1271. bpf_prog_put(prog);
  1272. out_free_tp:
  1273. kfree(raw_tp);
  1274. return err;
  1275. }
  1276. static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
  1277. enum bpf_attach_type attach_type)
  1278. {
  1279. switch (prog->type) {
  1280. case BPF_PROG_TYPE_CGROUP_SOCK:
  1281. case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  1282. return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
  1283. default:
  1284. return 0;
  1285. }
  1286. }
  1287. #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
  1288. #define BPF_F_ATTACH_MASK \
  1289. (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
  1290. static int bpf_prog_attach(const union bpf_attr *attr)
  1291. {
  1292. enum bpf_prog_type ptype;
  1293. struct bpf_prog *prog;
  1294. int ret;
  1295. if (!capable(CAP_NET_ADMIN))
  1296. return -EPERM;
  1297. if (CHECK_ATTR(BPF_PROG_ATTACH))
  1298. return -EINVAL;
  1299. if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
  1300. return -EINVAL;
  1301. switch (attr->attach_type) {
  1302. case BPF_CGROUP_INET_INGRESS:
  1303. case BPF_CGROUP_INET_EGRESS:
  1304. ptype = BPF_PROG_TYPE_CGROUP_SKB;
  1305. break;
  1306. case BPF_CGROUP_INET_SOCK_CREATE:
  1307. case BPF_CGROUP_INET4_POST_BIND:
  1308. case BPF_CGROUP_INET6_POST_BIND:
  1309. ptype = BPF_PROG_TYPE_CGROUP_SOCK;
  1310. break;
  1311. case BPF_CGROUP_INET4_BIND:
  1312. case BPF_CGROUP_INET6_BIND:
  1313. case BPF_CGROUP_INET4_CONNECT:
  1314. case BPF_CGROUP_INET6_CONNECT:
  1315. case BPF_CGROUP_UDP4_SENDMSG:
  1316. case BPF_CGROUP_UDP6_SENDMSG:
  1317. ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
  1318. break;
  1319. case BPF_CGROUP_SOCK_OPS:
  1320. ptype = BPF_PROG_TYPE_SOCK_OPS;
  1321. break;
  1322. case BPF_CGROUP_DEVICE:
  1323. ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
  1324. break;
  1325. case BPF_SK_MSG_VERDICT:
  1326. ptype = BPF_PROG_TYPE_SK_MSG;
  1327. break;
  1328. case BPF_SK_SKB_STREAM_PARSER:
  1329. case BPF_SK_SKB_STREAM_VERDICT:
  1330. ptype = BPF_PROG_TYPE_SK_SKB;
  1331. break;
  1332. case BPF_LIRC_MODE2:
  1333. ptype = BPF_PROG_TYPE_LIRC_MODE2;
  1334. break;
  1335. default:
  1336. return -EINVAL;
  1337. }
  1338. prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
  1339. if (IS_ERR(prog))
  1340. return PTR_ERR(prog);
  1341. if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
  1342. bpf_prog_put(prog);
  1343. return -EINVAL;
  1344. }
  1345. switch (ptype) {
  1346. case BPF_PROG_TYPE_SK_SKB:
  1347. case BPF_PROG_TYPE_SK_MSG:
  1348. ret = sockmap_get_from_fd(attr, ptype, prog);
  1349. break;
  1350. case BPF_PROG_TYPE_LIRC_MODE2:
  1351. ret = lirc_prog_attach(attr, prog);
  1352. break;
  1353. default:
  1354. ret = cgroup_bpf_prog_attach(attr, ptype, prog);
  1355. }
  1356. if (ret)
  1357. bpf_prog_put(prog);
  1358. return ret;
  1359. }
  1360. #define BPF_PROG_DETACH_LAST_FIELD attach_type
  1361. static int bpf_prog_detach(const union bpf_attr *attr)
  1362. {
  1363. enum bpf_prog_type ptype;
  1364. if (!capable(CAP_NET_ADMIN))
  1365. return -EPERM;
  1366. if (CHECK_ATTR(BPF_PROG_DETACH))
  1367. return -EINVAL;
  1368. switch (attr->attach_type) {
  1369. case BPF_CGROUP_INET_INGRESS:
  1370. case BPF_CGROUP_INET_EGRESS:
  1371. ptype = BPF_PROG_TYPE_CGROUP_SKB;
  1372. break;
  1373. case BPF_CGROUP_INET_SOCK_CREATE:
  1374. case BPF_CGROUP_INET4_POST_BIND:
  1375. case BPF_CGROUP_INET6_POST_BIND:
  1376. ptype = BPF_PROG_TYPE_CGROUP_SOCK;
  1377. break;
  1378. case BPF_CGROUP_INET4_BIND:
  1379. case BPF_CGROUP_INET6_BIND:
  1380. case BPF_CGROUP_INET4_CONNECT:
  1381. case BPF_CGROUP_INET6_CONNECT:
  1382. case BPF_CGROUP_UDP4_SENDMSG:
  1383. case BPF_CGROUP_UDP6_SENDMSG:
  1384. ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
  1385. break;
  1386. case BPF_CGROUP_SOCK_OPS:
  1387. ptype = BPF_PROG_TYPE_SOCK_OPS;
  1388. break;
  1389. case BPF_CGROUP_DEVICE:
  1390. ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
  1391. break;
  1392. case BPF_SK_MSG_VERDICT:
  1393. return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, NULL);
  1394. case BPF_SK_SKB_STREAM_PARSER:
  1395. case BPF_SK_SKB_STREAM_VERDICT:
  1396. return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, NULL);
  1397. case BPF_LIRC_MODE2:
  1398. return lirc_prog_detach(attr);
  1399. default:
  1400. return -EINVAL;
  1401. }
  1402. return cgroup_bpf_prog_detach(attr, ptype);
  1403. }
  1404. #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
  1405. static int bpf_prog_query(const union bpf_attr *attr,
  1406. union bpf_attr __user *uattr)
  1407. {
  1408. if (!capable(CAP_NET_ADMIN))
  1409. return -EPERM;
  1410. if (CHECK_ATTR(BPF_PROG_QUERY))
  1411. return -EINVAL;
  1412. if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
  1413. return -EINVAL;
  1414. switch (attr->query.attach_type) {
  1415. case BPF_CGROUP_INET_INGRESS:
  1416. case BPF_CGROUP_INET_EGRESS:
  1417. case BPF_CGROUP_INET_SOCK_CREATE:
  1418. case BPF_CGROUP_INET4_BIND:
  1419. case BPF_CGROUP_INET6_BIND:
  1420. case BPF_CGROUP_INET4_POST_BIND:
  1421. case BPF_CGROUP_INET6_POST_BIND:
  1422. case BPF_CGROUP_INET4_CONNECT:
  1423. case BPF_CGROUP_INET6_CONNECT:
  1424. case BPF_CGROUP_UDP4_SENDMSG:
  1425. case BPF_CGROUP_UDP6_SENDMSG:
  1426. case BPF_CGROUP_SOCK_OPS:
  1427. case BPF_CGROUP_DEVICE:
  1428. break;
  1429. case BPF_LIRC_MODE2:
  1430. return lirc_prog_query(attr, uattr);
  1431. default:
  1432. return -EINVAL;
  1433. }
  1434. return cgroup_bpf_prog_query(attr, uattr);
  1435. }
  1436. #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
  1437. static int bpf_prog_test_run(const union bpf_attr *attr,
  1438. union bpf_attr __user *uattr)
  1439. {
  1440. struct bpf_prog *prog;
  1441. int ret = -ENOTSUPP;
  1442. if (!capable(CAP_SYS_ADMIN))
  1443. return -EPERM;
  1444. if (CHECK_ATTR(BPF_PROG_TEST_RUN))
  1445. return -EINVAL;
  1446. prog = bpf_prog_get(attr->test.prog_fd);
  1447. if (IS_ERR(prog))
  1448. return PTR_ERR(prog);
  1449. if (prog->aux->ops->test_run)
  1450. ret = prog->aux->ops->test_run(prog, attr, uattr);
  1451. bpf_prog_put(prog);
  1452. return ret;
  1453. }
  1454. #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
  1455. static int bpf_obj_get_next_id(const union bpf_attr *attr,
  1456. union bpf_attr __user *uattr,
  1457. struct idr *idr,
  1458. spinlock_t *lock)
  1459. {
  1460. u32 next_id = attr->start_id;
  1461. int err = 0;
  1462. if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
  1463. return -EINVAL;
  1464. if (!capable(CAP_SYS_ADMIN))
  1465. return -EPERM;
  1466. next_id++;
  1467. spin_lock_bh(lock);
  1468. if (!idr_get_next(idr, &next_id))
  1469. err = -ENOENT;
  1470. spin_unlock_bh(lock);
  1471. if (!err)
  1472. err = put_user(next_id, &uattr->next_id);
  1473. return err;
  1474. }
  1475. #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
  1476. static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
  1477. {
  1478. struct bpf_prog *prog;
  1479. u32 id = attr->prog_id;
  1480. int fd;
  1481. if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
  1482. return -EINVAL;
  1483. if (!capable(CAP_SYS_ADMIN))
  1484. return -EPERM;
  1485. spin_lock_bh(&prog_idr_lock);
  1486. prog = idr_find(&prog_idr, id);
  1487. if (prog)
  1488. prog = bpf_prog_inc_not_zero(prog);
  1489. else
  1490. prog = ERR_PTR(-ENOENT);
  1491. spin_unlock_bh(&prog_idr_lock);
  1492. if (IS_ERR(prog))
  1493. return PTR_ERR(prog);
  1494. fd = bpf_prog_new_fd(prog);
  1495. if (fd < 0)
  1496. bpf_prog_put(prog);
  1497. return fd;
  1498. }
  1499. #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
  1500. static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
  1501. {
  1502. struct bpf_map *map;
  1503. u32 id = attr->map_id;
  1504. int f_flags;
  1505. int fd;
  1506. if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
  1507. attr->open_flags & ~BPF_OBJ_FLAG_MASK)
  1508. return -EINVAL;
  1509. if (!capable(CAP_SYS_ADMIN))
  1510. return -EPERM;
  1511. f_flags = bpf_get_file_flag(attr->open_flags);
  1512. if (f_flags < 0)
  1513. return f_flags;
  1514. spin_lock_bh(&map_idr_lock);
  1515. map = idr_find(&map_idr, id);
  1516. if (map)
  1517. map = bpf_map_inc_not_zero(map, true);
  1518. else
  1519. map = ERR_PTR(-ENOENT);
  1520. spin_unlock_bh(&map_idr_lock);
  1521. if (IS_ERR(map))
  1522. return PTR_ERR(map);
  1523. fd = bpf_map_new_fd(map, f_flags);
  1524. if (fd < 0)
  1525. bpf_map_put(map);
  1526. return fd;
  1527. }
  1528. static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
  1529. unsigned long addr)
  1530. {
  1531. int i;
  1532. for (i = 0; i < prog->aux->used_map_cnt; i++)
  1533. if (prog->aux->used_maps[i] == (void *)addr)
  1534. return prog->aux->used_maps[i];
  1535. return NULL;
  1536. }
  1537. static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
  1538. {
  1539. const struct bpf_map *map;
  1540. struct bpf_insn *insns;
  1541. u64 imm;
  1542. int i;
  1543. insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
  1544. GFP_USER);
  1545. if (!insns)
  1546. return insns;
  1547. for (i = 0; i < prog->len; i++) {
  1548. if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
  1549. insns[i].code = BPF_JMP | BPF_CALL;
  1550. insns[i].imm = BPF_FUNC_tail_call;
  1551. /* fall-through */
  1552. }
  1553. if (insns[i].code == (BPF_JMP | BPF_CALL) ||
  1554. insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
  1555. if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
  1556. insns[i].code = BPF_JMP | BPF_CALL;
  1557. if (!bpf_dump_raw_ok())
  1558. insns[i].imm = 0;
  1559. continue;
  1560. }
  1561. if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
  1562. continue;
  1563. imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
  1564. map = bpf_map_from_imm(prog, imm);
  1565. if (map) {
  1566. insns[i].src_reg = BPF_PSEUDO_MAP_FD;
  1567. insns[i].imm = map->id;
  1568. insns[i + 1].imm = 0;
  1569. continue;
  1570. }
  1571. if (!bpf_dump_raw_ok() &&
  1572. imm == (unsigned long)prog->aux) {
  1573. insns[i].imm = 0;
  1574. insns[i + 1].imm = 0;
  1575. continue;
  1576. }
  1577. }
  1578. return insns;
  1579. }
  1580. static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
  1581. const union bpf_attr *attr,
  1582. union bpf_attr __user *uattr)
  1583. {
  1584. struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  1585. struct bpf_prog_info info = {};
  1586. u32 info_len = attr->info.info_len;
  1587. char __user *uinsns;
  1588. u32 ulen;
  1589. int err;
  1590. err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
  1591. if (err)
  1592. return err;
  1593. info_len = min_t(u32, sizeof(info), info_len);
  1594. if (copy_from_user(&info, uinfo, info_len))
  1595. return -EFAULT;
  1596. info.type = prog->type;
  1597. info.id = prog->aux->id;
  1598. info.load_time = prog->aux->load_time;
  1599. info.created_by_uid = from_kuid_munged(current_user_ns(),
  1600. prog->aux->user->uid);
  1601. info.gpl_compatible = prog->gpl_compatible;
  1602. memcpy(info.tag, prog->tag, sizeof(prog->tag));
  1603. memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
  1604. ulen = info.nr_map_ids;
  1605. info.nr_map_ids = prog->aux->used_map_cnt;
  1606. ulen = min_t(u32, info.nr_map_ids, ulen);
  1607. if (ulen) {
  1608. u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
  1609. u32 i;
  1610. for (i = 0; i < ulen; i++)
  1611. if (put_user(prog->aux->used_maps[i]->id,
  1612. &user_map_ids[i]))
  1613. return -EFAULT;
  1614. }
  1615. if (!capable(CAP_SYS_ADMIN)) {
  1616. info.jited_prog_len = 0;
  1617. info.xlated_prog_len = 0;
  1618. info.nr_jited_ksyms = 0;
  1619. goto done;
  1620. }
  1621. ulen = info.xlated_prog_len;
  1622. info.xlated_prog_len = bpf_prog_insn_size(prog);
  1623. if (info.xlated_prog_len && ulen) {
  1624. struct bpf_insn *insns_sanitized;
  1625. bool fault;
  1626. if (prog->blinded && !bpf_dump_raw_ok()) {
  1627. info.xlated_prog_insns = 0;
  1628. goto done;
  1629. }
  1630. insns_sanitized = bpf_insn_prepare_dump(prog);
  1631. if (!insns_sanitized)
  1632. return -ENOMEM;
  1633. uinsns = u64_to_user_ptr(info.xlated_prog_insns);
  1634. ulen = min_t(u32, info.xlated_prog_len, ulen);
  1635. fault = copy_to_user(uinsns, insns_sanitized, ulen);
  1636. kfree(insns_sanitized);
  1637. if (fault)
  1638. return -EFAULT;
  1639. }
  1640. if (bpf_prog_is_dev_bound(prog->aux)) {
  1641. err = bpf_prog_offload_info_fill(&info, prog);
  1642. if (err)
  1643. return err;
  1644. goto done;
  1645. }
  1646. /* NOTE: the following code is supposed to be skipped for offload.
  1647. * bpf_prog_offload_info_fill() is the place to fill similar fields
  1648. * for offload.
  1649. */
  1650. ulen = info.jited_prog_len;
  1651. if (prog->aux->func_cnt) {
  1652. u32 i;
  1653. info.jited_prog_len = 0;
  1654. for (i = 0; i < prog->aux->func_cnt; i++)
  1655. info.jited_prog_len += prog->aux->func[i]->jited_len;
  1656. } else {
  1657. info.jited_prog_len = prog->jited_len;
  1658. }
  1659. if (info.jited_prog_len && ulen) {
  1660. if (bpf_dump_raw_ok()) {
  1661. uinsns = u64_to_user_ptr(info.jited_prog_insns);
  1662. ulen = min_t(u32, info.jited_prog_len, ulen);
  1663. /* for multi-function programs, copy the JITed
  1664. * instructions for all the functions
  1665. */
  1666. if (prog->aux->func_cnt) {
  1667. u32 len, free, i;
  1668. u8 *img;
  1669. free = ulen;
  1670. for (i = 0; i < prog->aux->func_cnt; i++) {
  1671. len = prog->aux->func[i]->jited_len;
  1672. len = min_t(u32, len, free);
  1673. img = (u8 *) prog->aux->func[i]->bpf_func;
  1674. if (copy_to_user(uinsns, img, len))
  1675. return -EFAULT;
  1676. uinsns += len;
  1677. free -= len;
  1678. if (!free)
  1679. break;
  1680. }
  1681. } else {
  1682. if (copy_to_user(uinsns, prog->bpf_func, ulen))
  1683. return -EFAULT;
  1684. }
  1685. } else {
  1686. info.jited_prog_insns = 0;
  1687. }
  1688. }
  1689. ulen = info.nr_jited_ksyms;
  1690. info.nr_jited_ksyms = prog->aux->func_cnt;
  1691. if (info.nr_jited_ksyms && ulen) {
  1692. if (bpf_dump_raw_ok()) {
  1693. u64 __user *user_ksyms;
  1694. ulong ksym_addr;
  1695. u32 i;
  1696. /* copy the address of the kernel symbol
  1697. * corresponding to each function
  1698. */
  1699. ulen = min_t(u32, info.nr_jited_ksyms, ulen);
  1700. user_ksyms = u64_to_user_ptr(info.jited_ksyms);
  1701. for (i = 0; i < ulen; i++) {
  1702. ksym_addr = (ulong) prog->aux->func[i]->bpf_func;
  1703. ksym_addr &= PAGE_MASK;
  1704. if (put_user((u64) ksym_addr, &user_ksyms[i]))
  1705. return -EFAULT;
  1706. }
  1707. } else {
  1708. info.jited_ksyms = 0;
  1709. }
  1710. }
  1711. ulen = info.nr_jited_func_lens;
  1712. info.nr_jited_func_lens = prog->aux->func_cnt;
  1713. if (info.nr_jited_func_lens && ulen) {
  1714. if (bpf_dump_raw_ok()) {
  1715. u32 __user *user_lens;
  1716. u32 func_len, i;
  1717. /* copy the JITed image lengths for each function */
  1718. ulen = min_t(u32, info.nr_jited_func_lens, ulen);
  1719. user_lens = u64_to_user_ptr(info.jited_func_lens);
  1720. for (i = 0; i < ulen; i++) {
  1721. func_len = prog->aux->func[i]->jited_len;
  1722. if (put_user(func_len, &user_lens[i]))
  1723. return -EFAULT;
  1724. }
  1725. } else {
  1726. info.jited_func_lens = 0;
  1727. }
  1728. }
  1729. done:
  1730. if (copy_to_user(uinfo, &info, info_len) ||
  1731. put_user(info_len, &uattr->info.info_len))
  1732. return -EFAULT;
  1733. return 0;
  1734. }
  1735. static int bpf_map_get_info_by_fd(struct bpf_map *map,
  1736. const union bpf_attr *attr,
  1737. union bpf_attr __user *uattr)
  1738. {
  1739. struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  1740. struct bpf_map_info info = {};
  1741. u32 info_len = attr->info.info_len;
  1742. int err;
  1743. err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
  1744. if (err)
  1745. return err;
  1746. info_len = min_t(u32, sizeof(info), info_len);
  1747. info.type = map->map_type;
  1748. info.id = map->id;
  1749. info.key_size = map->key_size;
  1750. info.value_size = map->value_size;
  1751. info.max_entries = map->max_entries;
  1752. info.map_flags = map->map_flags;
  1753. memcpy(info.name, map->name, sizeof(map->name));
  1754. if (map->btf) {
  1755. info.btf_id = btf_id(map->btf);
  1756. info.btf_key_type_id = map->btf_key_type_id;
  1757. info.btf_value_type_id = map->btf_value_type_id;
  1758. }
  1759. if (bpf_map_is_dev_bound(map)) {
  1760. err = bpf_map_offload_info_fill(&info, map);
  1761. if (err)
  1762. return err;
  1763. }
  1764. if (copy_to_user(uinfo, &info, info_len) ||
  1765. put_user(info_len, &uattr->info.info_len))
  1766. return -EFAULT;
  1767. return 0;
  1768. }
  1769. static int bpf_btf_get_info_by_fd(struct btf *btf,
  1770. const union bpf_attr *attr,
  1771. union bpf_attr __user *uattr)
  1772. {
  1773. struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  1774. u32 info_len = attr->info.info_len;
  1775. int err;
  1776. err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
  1777. if (err)
  1778. return err;
  1779. return btf_get_info_by_fd(btf, attr, uattr);
  1780. }
  1781. #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
  1782. static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
  1783. union bpf_attr __user *uattr)
  1784. {
  1785. int ufd = attr->info.bpf_fd;
  1786. struct fd f;
  1787. int err;
  1788. if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
  1789. return -EINVAL;
  1790. f = fdget(ufd);
  1791. if (!f.file)
  1792. return -EBADFD;
  1793. if (f.file->f_op == &bpf_prog_fops)
  1794. err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
  1795. uattr);
  1796. else if (f.file->f_op == &bpf_map_fops)
  1797. err = bpf_map_get_info_by_fd(f.file->private_data, attr,
  1798. uattr);
  1799. else if (f.file->f_op == &btf_fops)
  1800. err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
  1801. else
  1802. err = -EINVAL;
  1803. fdput(f);
  1804. return err;
  1805. }
  1806. #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
  1807. static int bpf_btf_load(const union bpf_attr *attr)
  1808. {
  1809. if (CHECK_ATTR(BPF_BTF_LOAD))
  1810. return -EINVAL;
  1811. if (!capable(CAP_SYS_ADMIN))
  1812. return -EPERM;
  1813. return btf_new_fd(attr);
  1814. }
  1815. #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
  1816. static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
  1817. {
  1818. if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
  1819. return -EINVAL;
  1820. if (!capable(CAP_SYS_ADMIN))
  1821. return -EPERM;
  1822. return btf_get_fd_by_id(attr->btf_id);
  1823. }
  1824. static int bpf_task_fd_query_copy(const union bpf_attr *attr,
  1825. union bpf_attr __user *uattr,
  1826. u32 prog_id, u32 fd_type,
  1827. const char *buf, u64 probe_offset,
  1828. u64 probe_addr)
  1829. {
  1830. char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
  1831. u32 len = buf ? strlen(buf) : 0, input_len;
  1832. int err = 0;
  1833. if (put_user(len, &uattr->task_fd_query.buf_len))
  1834. return -EFAULT;
  1835. input_len = attr->task_fd_query.buf_len;
  1836. if (input_len && ubuf) {
  1837. if (!len) {
  1838. /* nothing to copy, just make ubuf NULL terminated */
  1839. char zero = '\0';
  1840. if (put_user(zero, ubuf))
  1841. return -EFAULT;
  1842. } else if (input_len >= len + 1) {
  1843. /* ubuf can hold the string with NULL terminator */
  1844. if (copy_to_user(ubuf, buf, len + 1))
  1845. return -EFAULT;
  1846. } else {
  1847. /* ubuf cannot hold the string with NULL terminator,
  1848. * do a partial copy with NULL terminator.
  1849. */
  1850. char zero = '\0';
  1851. err = -ENOSPC;
  1852. if (copy_to_user(ubuf, buf, input_len - 1))
  1853. return -EFAULT;
  1854. if (put_user(zero, ubuf + input_len - 1))
  1855. return -EFAULT;
  1856. }
  1857. }
  1858. if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
  1859. put_user(fd_type, &uattr->task_fd_query.fd_type) ||
  1860. put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
  1861. put_user(probe_addr, &uattr->task_fd_query.probe_addr))
  1862. return -EFAULT;
  1863. return err;
  1864. }
  1865. #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
  1866. static int bpf_task_fd_query(const union bpf_attr *attr,
  1867. union bpf_attr __user *uattr)
  1868. {
  1869. pid_t pid = attr->task_fd_query.pid;
  1870. u32 fd = attr->task_fd_query.fd;
  1871. const struct perf_event *event;
  1872. struct files_struct *files;
  1873. struct task_struct *task;
  1874. struct file *file;
  1875. int err;
  1876. if (CHECK_ATTR(BPF_TASK_FD_QUERY))
  1877. return -EINVAL;
  1878. if (!capable(CAP_SYS_ADMIN))
  1879. return -EPERM;
  1880. if (attr->task_fd_query.flags != 0)
  1881. return -EINVAL;
  1882. task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
  1883. if (!task)
  1884. return -ENOENT;
  1885. files = get_files_struct(task);
  1886. put_task_struct(task);
  1887. if (!files)
  1888. return -ENOENT;
  1889. err = 0;
  1890. spin_lock(&files->file_lock);
  1891. file = fcheck_files(files, fd);
  1892. if (!file)
  1893. err = -EBADF;
  1894. else
  1895. get_file(file);
  1896. spin_unlock(&files->file_lock);
  1897. put_files_struct(files);
  1898. if (err)
  1899. goto out;
  1900. if (file->f_op == &bpf_raw_tp_fops) {
  1901. struct bpf_raw_tracepoint *raw_tp = file->private_data;
  1902. struct bpf_raw_event_map *btp = raw_tp->btp;
  1903. err = bpf_task_fd_query_copy(attr, uattr,
  1904. raw_tp->prog->aux->id,
  1905. BPF_FD_TYPE_RAW_TRACEPOINT,
  1906. btp->tp->name, 0, 0);
  1907. goto put_file;
  1908. }
  1909. event = perf_get_event(file);
  1910. if (!IS_ERR(event)) {
  1911. u64 probe_offset, probe_addr;
  1912. u32 prog_id, fd_type;
  1913. const char *buf;
  1914. err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
  1915. &buf, &probe_offset,
  1916. &probe_addr);
  1917. if (!err)
  1918. err = bpf_task_fd_query_copy(attr, uattr, prog_id,
  1919. fd_type, buf,
  1920. probe_offset,
  1921. probe_addr);
  1922. goto put_file;
  1923. }
  1924. err = -ENOTSUPP;
  1925. put_file:
  1926. fput(file);
  1927. out:
  1928. return err;
  1929. }
  1930. SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
  1931. {
  1932. union bpf_attr attr = {};
  1933. int err;
  1934. if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
  1935. return -EPERM;
  1936. err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
  1937. if (err)
  1938. return err;
  1939. size = min_t(u32, size, sizeof(attr));
  1940. /* copy attributes from user space, may be less than sizeof(bpf_attr) */
  1941. if (copy_from_user(&attr, uattr, size) != 0)
  1942. return -EFAULT;
  1943. err = security_bpf(cmd, &attr, size);
  1944. if (err < 0)
  1945. return err;
  1946. switch (cmd) {
  1947. case BPF_MAP_CREATE:
  1948. err = map_create(&attr);
  1949. break;
  1950. case BPF_MAP_LOOKUP_ELEM:
  1951. err = map_lookup_elem(&attr);
  1952. break;
  1953. case BPF_MAP_UPDATE_ELEM:
  1954. err = map_update_elem(&attr);
  1955. break;
  1956. case BPF_MAP_DELETE_ELEM:
  1957. err = map_delete_elem(&attr);
  1958. break;
  1959. case BPF_MAP_GET_NEXT_KEY:
  1960. err = map_get_next_key(&attr);
  1961. break;
  1962. case BPF_PROG_LOAD:
  1963. err = bpf_prog_load(&attr);
  1964. break;
  1965. case BPF_OBJ_PIN:
  1966. err = bpf_obj_pin(&attr);
  1967. break;
  1968. case BPF_OBJ_GET:
  1969. err = bpf_obj_get(&attr);
  1970. break;
  1971. case BPF_PROG_ATTACH:
  1972. err = bpf_prog_attach(&attr);
  1973. break;
  1974. case BPF_PROG_DETACH:
  1975. err = bpf_prog_detach(&attr);
  1976. break;
  1977. case BPF_PROG_QUERY:
  1978. err = bpf_prog_query(&attr, uattr);
  1979. break;
  1980. case BPF_PROG_TEST_RUN:
  1981. err = bpf_prog_test_run(&attr, uattr);
  1982. break;
  1983. case BPF_PROG_GET_NEXT_ID:
  1984. err = bpf_obj_get_next_id(&attr, uattr,
  1985. &prog_idr, &prog_idr_lock);
  1986. break;
  1987. case BPF_MAP_GET_NEXT_ID:
  1988. err = bpf_obj_get_next_id(&attr, uattr,
  1989. &map_idr, &map_idr_lock);
  1990. break;
  1991. case BPF_PROG_GET_FD_BY_ID:
  1992. err = bpf_prog_get_fd_by_id(&attr);
  1993. break;
  1994. case BPF_MAP_GET_FD_BY_ID:
  1995. err = bpf_map_get_fd_by_id(&attr);
  1996. break;
  1997. case BPF_OBJ_GET_INFO_BY_FD:
  1998. err = bpf_obj_get_info_by_fd(&attr, uattr);
  1999. break;
  2000. case BPF_RAW_TRACEPOINT_OPEN:
  2001. err = bpf_raw_tracepoint_open(&attr);
  2002. break;
  2003. case BPF_BTF_LOAD:
  2004. err = bpf_btf_load(&attr);
  2005. break;
  2006. case BPF_BTF_GET_FD_BY_ID:
  2007. err = bpf_btf_get_fd_by_id(&attr);
  2008. break;
  2009. case BPF_TASK_FD_QUERY:
  2010. err = bpf_task_fd_query(&attr, uattr);
  2011. break;
  2012. default:
  2013. err = -EINVAL;
  2014. break;
  2015. }
  2016. return err;
  2017. }