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 case BPF_CGROUP_UDP4_RECVMSG: 1585 case BPF_CGROUP_UDP6_RECVMSG: 1586 return 0; 1587 default: 1588 return -EINVAL; 1589 } 1590 default: 1591 return 0; 1592 } 1593 } 1594 1595 /* last field in 'union bpf_attr' used by this command */ 1596 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt 1597 1598 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 1599 { 1600 enum bpf_prog_type type = attr->prog_type; 1601 struct bpf_prog *prog; 1602 int err; 1603 char license[128]; 1604 bool is_gpl; 1605 1606 if (CHECK_ATTR(BPF_PROG_LOAD)) 1607 return -EINVAL; 1608 1609 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | BPF_F_ANY_ALIGNMENT)) 1610 return -EINVAL; 1611 1612 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 1613 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 1614 !capable(CAP_SYS_ADMIN)) 1615 return -EPERM; 1616 1617 /* copy eBPF program license from user space */ 1618 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 1619 sizeof(license) - 1) < 0) 1620 return -EFAULT; 1621 license[sizeof(license) - 1] = 0; 1622 1623 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 1624 is_gpl = license_is_gpl_compatible(license); 1625 1626 if (attr->insn_cnt == 0 || 1627 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 1628 return -E2BIG; 1629 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 1630 type != BPF_PROG_TYPE_CGROUP_SKB && 1631 !capable(CAP_SYS_ADMIN)) 1632 return -EPERM; 1633 1634 bpf_prog_load_fixup_attach_type(attr); 1635 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type)) 1636 return -EINVAL; 1637 1638 /* plain bpf_prog allocation */ 1639 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 1640 if (!prog) 1641 return -ENOMEM; 1642 1643 prog->expected_attach_type = attr->expected_attach_type; 1644 1645 prog->aux->offload_requested = !!attr->prog_ifindex; 1646 1647 err = security_bpf_prog_alloc(prog->aux); 1648 if (err) 1649 goto free_prog_nouncharge; 1650 1651 err = bpf_prog_charge_memlock(prog); 1652 if (err) 1653 goto free_prog_sec; 1654 1655 prog->len = attr->insn_cnt; 1656 1657 err = -EFAULT; 1658 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 1659 bpf_prog_insn_size(prog)) != 0) 1660 goto free_prog; 1661 1662 prog->orig_prog = NULL; 1663 prog->jited = 0; 1664 1665 atomic_set(&prog->aux->refcnt, 1); 1666 prog->gpl_compatible = is_gpl ? 1 : 0; 1667 1668 if (bpf_prog_is_dev_bound(prog->aux)) { 1669 err = bpf_prog_offload_init(prog, attr); 1670 if (err) 1671 goto free_prog; 1672 } 1673 1674 /* find program type: socket_filter vs tracing_filter */ 1675 err = find_prog_type(type, prog); 1676 if (err < 0) 1677 goto free_prog; 1678 1679 prog->aux->load_time = ktime_get_boot_ns(); 1680 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 1681 if (err) 1682 goto free_prog; 1683 1684 /* run eBPF verifier */ 1685 err = bpf_check(&prog, attr, uattr); 1686 if (err < 0) 1687 goto free_used_maps; 1688 1689 prog = bpf_prog_select_runtime(prog, &err); 1690 if (err < 0) 1691 goto free_used_maps; 1692 1693 err = bpf_prog_alloc_id(prog); 1694 if (err) 1695 goto free_used_maps; 1696 1697 err = bpf_prog_new_fd(prog); 1698 if (err < 0) { 1699 /* failed to allocate fd. 1700 * bpf_prog_put() is needed because the above 1701 * bpf_prog_alloc_id() has published the prog 1702 * to the userspace and the userspace may 1703 * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID. 1704 */ 1705 bpf_prog_put(prog); 1706 return err; 1707 } 1708 1709 bpf_prog_kallsyms_add(prog); 1710 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 1711 return err; 1712 1713 free_used_maps: 1714 bpf_prog_free_linfo(prog); 1715 kvfree(prog->aux->func_info); 1716 btf_put(prog->aux->btf); 1717 bpf_prog_kallsyms_del_subprogs(prog); 1718 free_used_maps(prog->aux); 1719 free_prog: 1720 bpf_prog_uncharge_memlock(prog); 1721 free_prog_sec: 1722 security_bpf_prog_free(prog->aux); 1723 free_prog_nouncharge: 1724 bpf_prog_free(prog); 1725 return err; 1726 } 1727 1728 #define BPF_OBJ_LAST_FIELD file_flags 1729 1730 static int bpf_obj_pin(const union bpf_attr *attr) 1731 { 1732 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 1733 return -EINVAL; 1734 1735 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 1736 } 1737 1738 static int bpf_obj_get(const union bpf_attr *attr) 1739 { 1740 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 1741 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 1742 return -EINVAL; 1743 1744 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 1745 attr->file_flags); 1746 } 1747 1748 struct bpf_raw_tracepoint { 1749 struct bpf_raw_event_map *btp; 1750 struct bpf_prog *prog; 1751 }; 1752 1753 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) 1754 { 1755 struct bpf_raw_tracepoint *raw_tp = filp->private_data; 1756 1757 if (raw_tp->prog) { 1758 bpf_probe_unregister(raw_tp->btp, raw_tp->prog); 1759 bpf_prog_put(raw_tp->prog); 1760 } 1761 bpf_put_raw_tracepoint(raw_tp->btp); 1762 kfree(raw_tp); 1763 return 0; 1764 } 1765 1766 static const struct file_operations bpf_raw_tp_fops = { 1767 .release = bpf_raw_tracepoint_release, 1768 .read = bpf_dummy_read, 1769 .write = bpf_dummy_write, 1770 }; 1771 1772 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 1773 1774 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 1775 { 1776 struct bpf_raw_tracepoint *raw_tp; 1777 struct bpf_raw_event_map *btp; 1778 struct bpf_prog *prog; 1779 char tp_name[128]; 1780 int tp_fd, err; 1781 1782 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name), 1783 sizeof(tp_name) - 1) < 0) 1784 return -EFAULT; 1785 tp_name[sizeof(tp_name) - 1] = 0; 1786 1787 btp = bpf_get_raw_tracepoint(tp_name); 1788 if (!btp) 1789 return -ENOENT; 1790 1791 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 1792 if (!raw_tp) { 1793 err = -ENOMEM; 1794 goto out_put_btp; 1795 } 1796 raw_tp->btp = btp; 1797 1798 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 1799 if (IS_ERR(prog)) { 1800 err = PTR_ERR(prog); 1801 goto out_free_tp; 1802 } 1803 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT && 1804 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) { 1805 err = -EINVAL; 1806 goto out_put_prog; 1807 } 1808 1809 err = bpf_probe_register(raw_tp->btp, prog); 1810 if (err) 1811 goto out_put_prog; 1812 1813 raw_tp->prog = prog; 1814 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp, 1815 O_CLOEXEC); 1816 if (tp_fd < 0) { 1817 bpf_probe_unregister(raw_tp->btp, prog); 1818 err = tp_fd; 1819 goto out_put_prog; 1820 } 1821 return tp_fd; 1822 1823 out_put_prog: 1824 bpf_prog_put(prog); 1825 out_free_tp: 1826 kfree(raw_tp); 1827 out_put_btp: 1828 bpf_put_raw_tracepoint(btp); 1829 return err; 1830 } 1831 1832 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 1833 enum bpf_attach_type attach_type) 1834 { 1835 switch (prog->type) { 1836 case BPF_PROG_TYPE_CGROUP_SOCK: 1837 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1838 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 1839 default: 1840 return 0; 1841 } 1842 } 1843 1844 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags 1845 1846 #define BPF_F_ATTACH_MASK \ 1847 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) 1848 1849 static int bpf_prog_attach(const union bpf_attr *attr) 1850 { 1851 enum bpf_prog_type ptype; 1852 struct bpf_prog *prog; 1853 int ret; 1854 1855 if (!capable(CAP_NET_ADMIN)) 1856 return -EPERM; 1857 1858 if (CHECK_ATTR(BPF_PROG_ATTACH)) 1859 return -EINVAL; 1860 1861 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 1862 return -EINVAL; 1863 1864 switch (attr->attach_type) { 1865 case BPF_CGROUP_INET_INGRESS: 1866 case BPF_CGROUP_INET_EGRESS: 1867 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1868 break; 1869 case BPF_CGROUP_INET_SOCK_CREATE: 1870 case BPF_CGROUP_INET4_POST_BIND: 1871 case BPF_CGROUP_INET6_POST_BIND: 1872 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1873 break; 1874 case BPF_CGROUP_INET4_BIND: 1875 case BPF_CGROUP_INET6_BIND: 1876 case BPF_CGROUP_INET4_CONNECT: 1877 case BPF_CGROUP_INET6_CONNECT: 1878 case BPF_CGROUP_UDP4_SENDMSG: 1879 case BPF_CGROUP_UDP6_SENDMSG: 1880 case BPF_CGROUP_UDP4_RECVMSG: 1881 case BPF_CGROUP_UDP6_RECVMSG: 1882 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1883 break; 1884 case BPF_CGROUP_SOCK_OPS: 1885 ptype = BPF_PROG_TYPE_SOCK_OPS; 1886 break; 1887 case BPF_CGROUP_DEVICE: 1888 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1889 break; 1890 case BPF_SK_MSG_VERDICT: 1891 ptype = BPF_PROG_TYPE_SK_MSG; 1892 break; 1893 case BPF_SK_SKB_STREAM_PARSER: 1894 case BPF_SK_SKB_STREAM_VERDICT: 1895 ptype = BPF_PROG_TYPE_SK_SKB; 1896 break; 1897 case BPF_LIRC_MODE2: 1898 ptype = BPF_PROG_TYPE_LIRC_MODE2; 1899 break; 1900 case BPF_FLOW_DISSECTOR: 1901 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR; 1902 break; 1903 case BPF_CGROUP_SYSCTL: 1904 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 1905 break; 1906 default: 1907 return -EINVAL; 1908 } 1909 1910 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1911 if (IS_ERR(prog)) 1912 return PTR_ERR(prog); 1913 1914 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 1915 bpf_prog_put(prog); 1916 return -EINVAL; 1917 } 1918 1919 switch (ptype) { 1920 case BPF_PROG_TYPE_SK_SKB: 1921 case BPF_PROG_TYPE_SK_MSG: 1922 ret = sock_map_get_from_fd(attr, prog); 1923 break; 1924 case BPF_PROG_TYPE_LIRC_MODE2: 1925 ret = lirc_prog_attach(attr, prog); 1926 break; 1927 case BPF_PROG_TYPE_FLOW_DISSECTOR: 1928 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 1929 break; 1930 default: 1931 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 1932 } 1933 1934 if (ret) 1935 bpf_prog_put(prog); 1936 return ret; 1937 } 1938 1939 #define BPF_PROG_DETACH_LAST_FIELD attach_type 1940 1941 static int bpf_prog_detach(const union bpf_attr *attr) 1942 { 1943 enum bpf_prog_type ptype; 1944 1945 if (!capable(CAP_NET_ADMIN)) 1946 return -EPERM; 1947 1948 if (CHECK_ATTR(BPF_PROG_DETACH)) 1949 return -EINVAL; 1950 1951 switch (attr->attach_type) { 1952 case BPF_CGROUP_INET_INGRESS: 1953 case BPF_CGROUP_INET_EGRESS: 1954 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1955 break; 1956 case BPF_CGROUP_INET_SOCK_CREATE: 1957 case BPF_CGROUP_INET4_POST_BIND: 1958 case BPF_CGROUP_INET6_POST_BIND: 1959 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1960 break; 1961 case BPF_CGROUP_INET4_BIND: 1962 case BPF_CGROUP_INET6_BIND: 1963 case BPF_CGROUP_INET4_CONNECT: 1964 case BPF_CGROUP_INET6_CONNECT: 1965 case BPF_CGROUP_UDP4_SENDMSG: 1966 case BPF_CGROUP_UDP6_SENDMSG: 1967 case BPF_CGROUP_UDP4_RECVMSG: 1968 case BPF_CGROUP_UDP6_RECVMSG: 1969 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1970 break; 1971 case BPF_CGROUP_SOCK_OPS: 1972 ptype = BPF_PROG_TYPE_SOCK_OPS; 1973 break; 1974 case BPF_CGROUP_DEVICE: 1975 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1976 break; 1977 case BPF_SK_MSG_VERDICT: 1978 return sock_map_get_from_fd(attr, NULL); 1979 case BPF_SK_SKB_STREAM_PARSER: 1980 case BPF_SK_SKB_STREAM_VERDICT: 1981 return sock_map_get_from_fd(attr, NULL); 1982 case BPF_LIRC_MODE2: 1983 return lirc_prog_detach(attr); 1984 case BPF_FLOW_DISSECTOR: 1985 return skb_flow_dissector_bpf_prog_detach(attr); 1986 case BPF_CGROUP_SYSCTL: 1987 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 1988 break; 1989 default: 1990 return -EINVAL; 1991 } 1992 1993 return cgroup_bpf_prog_detach(attr, ptype); 1994 } 1995 1996 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 1997 1998 static int bpf_prog_query(const union bpf_attr *attr, 1999 union bpf_attr __user *uattr) 2000 { 2001 if (!capable(CAP_NET_ADMIN)) 2002 return -EPERM; 2003 if (CHECK_ATTR(BPF_PROG_QUERY)) 2004 return -EINVAL; 2005 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2006 return -EINVAL; 2007 2008 switch (attr->query.attach_type) { 2009 case BPF_CGROUP_INET_INGRESS: 2010 case BPF_CGROUP_INET_EGRESS: 2011 case BPF_CGROUP_INET_SOCK_CREATE: 2012 case BPF_CGROUP_INET4_BIND: 2013 case BPF_CGROUP_INET6_BIND: 2014 case BPF_CGROUP_INET4_POST_BIND: 2015 case BPF_CGROUP_INET6_POST_BIND: 2016 case BPF_CGROUP_INET4_CONNECT: 2017 case BPF_CGROUP_INET6_CONNECT: 2018 case BPF_CGROUP_UDP4_SENDMSG: 2019 case BPF_CGROUP_UDP6_SENDMSG: 2020 case BPF_CGROUP_UDP4_RECVMSG: 2021 case BPF_CGROUP_UDP6_RECVMSG: 2022 case BPF_CGROUP_SOCK_OPS: 2023 case BPF_CGROUP_DEVICE: 2024 case BPF_CGROUP_SYSCTL: 2025 break; 2026 case BPF_LIRC_MODE2: 2027 return lirc_prog_query(attr, uattr); 2028 case BPF_FLOW_DISSECTOR: 2029 return skb_flow_dissector_prog_query(attr, uattr); 2030 default: 2031 return -EINVAL; 2032 } 2033 2034 return cgroup_bpf_prog_query(attr, uattr); 2035 } 2036 2037 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2038 2039 static int bpf_prog_test_run(const union bpf_attr *attr, 2040 union bpf_attr __user *uattr) 2041 { 2042 struct bpf_prog *prog; 2043 int ret = -ENOTSUPP; 2044 2045 if (!capable(CAP_SYS_ADMIN)) 2046 return -EPERM; 2047 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2048 return -EINVAL; 2049 2050 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2051 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2052 return -EINVAL; 2053 2054 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2055 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2056 return -EINVAL; 2057 2058 prog = bpf_prog_get(attr->test.prog_fd); 2059 if (IS_ERR(prog)) 2060 return PTR_ERR(prog); 2061 2062 if (prog->aux->ops->test_run) 2063 ret = prog->aux->ops->test_run(prog, attr, uattr); 2064 2065 bpf_prog_put(prog); 2066 return ret; 2067 } 2068 2069 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2070 2071 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2072 union bpf_attr __user *uattr, 2073 struct idr *idr, 2074 spinlock_t *lock) 2075 { 2076 u32 next_id = attr->start_id; 2077 int err = 0; 2078 2079 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2080 return -EINVAL; 2081 2082 if (!capable(CAP_SYS_ADMIN)) 2083 return -EPERM; 2084 2085 next_id++; 2086 spin_lock_bh(lock); 2087 if (!idr_get_next(idr, &next_id)) 2088 err = -ENOENT; 2089 spin_unlock_bh(lock); 2090 2091 if (!err) 2092 err = put_user(next_id, &uattr->next_id); 2093 2094 return err; 2095 } 2096 2097 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2098 2099 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2100 { 2101 struct bpf_prog *prog; 2102 u32 id = attr->prog_id; 2103 int fd; 2104 2105 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2106 return -EINVAL; 2107 2108 if (!capable(CAP_SYS_ADMIN)) 2109 return -EPERM; 2110 2111 spin_lock_bh(&prog_idr_lock); 2112 prog = idr_find(&prog_idr, id); 2113 if (prog) 2114 prog = bpf_prog_inc_not_zero(prog); 2115 else 2116 prog = ERR_PTR(-ENOENT); 2117 spin_unlock_bh(&prog_idr_lock); 2118 2119 if (IS_ERR(prog)) 2120 return PTR_ERR(prog); 2121 2122 fd = bpf_prog_new_fd(prog); 2123 if (fd < 0) 2124 bpf_prog_put(prog); 2125 2126 return fd; 2127 } 2128 2129 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2130 2131 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2132 { 2133 struct bpf_map *map; 2134 u32 id = attr->map_id; 2135 int f_flags; 2136 int fd; 2137 2138 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2139 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2140 return -EINVAL; 2141 2142 if (!capable(CAP_SYS_ADMIN)) 2143 return -EPERM; 2144 2145 f_flags = bpf_get_file_flag(attr->open_flags); 2146 if (f_flags < 0) 2147 return f_flags; 2148 2149 spin_lock_bh(&map_idr_lock); 2150 map = idr_find(&map_idr, id); 2151 if (map) 2152 map = bpf_map_inc_not_zero(map, true); 2153 else 2154 map = ERR_PTR(-ENOENT); 2155 spin_unlock_bh(&map_idr_lock); 2156 2157 if (IS_ERR(map)) 2158 return PTR_ERR(map); 2159 2160 fd = bpf_map_new_fd(map, f_flags); 2161 if (fd < 0) 2162 bpf_map_put_with_uref(map); 2163 2164 return fd; 2165 } 2166 2167 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2168 unsigned long addr, u32 *off, 2169 u32 *type) 2170 { 2171 const struct bpf_map *map; 2172 int i; 2173 2174 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2175 map = prog->aux->used_maps[i]; 2176 if (map == (void *)addr) { 2177 *type = BPF_PSEUDO_MAP_FD; 2178 return map; 2179 } 2180 if (!map->ops->map_direct_value_meta) 2181 continue; 2182 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2183 *type = BPF_PSEUDO_MAP_VALUE; 2184 return map; 2185 } 2186 } 2187 2188 return NULL; 2189 } 2190 2191 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2192 { 2193 const struct bpf_map *map; 2194 struct bpf_insn *insns; 2195 u32 off, type; 2196 u64 imm; 2197 int i; 2198 2199 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2200 GFP_USER); 2201 if (!insns) 2202 return insns; 2203 2204 for (i = 0; i < prog->len; i++) { 2205 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2206 insns[i].code = BPF_JMP | BPF_CALL; 2207 insns[i].imm = BPF_FUNC_tail_call; 2208 /* fall-through */ 2209 } 2210 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2211 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2212 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2213 insns[i].code = BPF_JMP | BPF_CALL; 2214 if (!bpf_dump_raw_ok()) 2215 insns[i].imm = 0; 2216 continue; 2217 } 2218 2219 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2220 continue; 2221 2222 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2223 map = bpf_map_from_imm(prog, imm, &off, &type); 2224 if (map) { 2225 insns[i].src_reg = type; 2226 insns[i].imm = map->id; 2227 insns[i + 1].imm = off; 2228 continue; 2229 } 2230 } 2231 2232 return insns; 2233 } 2234 2235 static int set_info_rec_size(struct bpf_prog_info *info) 2236 { 2237 /* 2238 * Ensure info.*_rec_size is the same as kernel expected size 2239 * 2240 * or 2241 * 2242 * Only allow zero *_rec_size if both _rec_size and _cnt are 2243 * zero. In this case, the kernel will set the expected 2244 * _rec_size back to the info. 2245 */ 2246 2247 if ((info->nr_func_info || info->func_info_rec_size) && 2248 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2249 return -EINVAL; 2250 2251 if ((info->nr_line_info || info->line_info_rec_size) && 2252 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2253 return -EINVAL; 2254 2255 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2256 info->jited_line_info_rec_size != sizeof(__u64)) 2257 return -EINVAL; 2258 2259 info->func_info_rec_size = sizeof(struct bpf_func_info); 2260 info->line_info_rec_size = sizeof(struct bpf_line_info); 2261 info->jited_line_info_rec_size = sizeof(__u64); 2262 2263 return 0; 2264 } 2265 2266 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2267 const union bpf_attr *attr, 2268 union bpf_attr __user *uattr) 2269 { 2270 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2271 struct bpf_prog_info info = {}; 2272 u32 info_len = attr->info.info_len; 2273 struct bpf_prog_stats stats; 2274 char __user *uinsns; 2275 u32 ulen; 2276 int err; 2277 2278 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2279 if (err) 2280 return err; 2281 info_len = min_t(u32, sizeof(info), info_len); 2282 2283 if (copy_from_user(&info, uinfo, info_len)) 2284 return -EFAULT; 2285 2286 info.type = prog->type; 2287 info.id = prog->aux->id; 2288 info.load_time = prog->aux->load_time; 2289 info.created_by_uid = from_kuid_munged(current_user_ns(), 2290 prog->aux->user->uid); 2291 info.gpl_compatible = prog->gpl_compatible; 2292 2293 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 2294 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 2295 2296 ulen = info.nr_map_ids; 2297 info.nr_map_ids = prog->aux->used_map_cnt; 2298 ulen = min_t(u32, info.nr_map_ids, ulen); 2299 if (ulen) { 2300 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 2301 u32 i; 2302 2303 for (i = 0; i < ulen; i++) 2304 if (put_user(prog->aux->used_maps[i]->id, 2305 &user_map_ids[i])) 2306 return -EFAULT; 2307 } 2308 2309 err = set_info_rec_size(&info); 2310 if (err) 2311 return err; 2312 2313 bpf_prog_get_stats(prog, &stats); 2314 info.run_time_ns = stats.nsecs; 2315 info.run_cnt = stats.cnt; 2316 2317 if (!capable(CAP_SYS_ADMIN)) { 2318 info.jited_prog_len = 0; 2319 info.xlated_prog_len = 0; 2320 info.nr_jited_ksyms = 0; 2321 info.nr_jited_func_lens = 0; 2322 info.nr_func_info = 0; 2323 info.nr_line_info = 0; 2324 info.nr_jited_line_info = 0; 2325 goto done; 2326 } 2327 2328 ulen = info.xlated_prog_len; 2329 info.xlated_prog_len = bpf_prog_insn_size(prog); 2330 if (info.xlated_prog_len && ulen) { 2331 struct bpf_insn *insns_sanitized; 2332 bool fault; 2333 2334 if (prog->blinded && !bpf_dump_raw_ok()) { 2335 info.xlated_prog_insns = 0; 2336 goto done; 2337 } 2338 insns_sanitized = bpf_insn_prepare_dump(prog); 2339 if (!insns_sanitized) 2340 return -ENOMEM; 2341 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 2342 ulen = min_t(u32, info.xlated_prog_len, ulen); 2343 fault = copy_to_user(uinsns, insns_sanitized, ulen); 2344 kfree(insns_sanitized); 2345 if (fault) 2346 return -EFAULT; 2347 } 2348 2349 if (bpf_prog_is_dev_bound(prog->aux)) { 2350 err = bpf_prog_offload_info_fill(&info, prog); 2351 if (err) 2352 return err; 2353 goto done; 2354 } 2355 2356 /* NOTE: the following code is supposed to be skipped for offload. 2357 * bpf_prog_offload_info_fill() is the place to fill similar fields 2358 * for offload. 2359 */ 2360 ulen = info.jited_prog_len; 2361 if (prog->aux->func_cnt) { 2362 u32 i; 2363 2364 info.jited_prog_len = 0; 2365 for (i = 0; i < prog->aux->func_cnt; i++) 2366 info.jited_prog_len += prog->aux->func[i]->jited_len; 2367 } else { 2368 info.jited_prog_len = prog->jited_len; 2369 } 2370 2371 if (info.jited_prog_len && ulen) { 2372 if (bpf_dump_raw_ok()) { 2373 uinsns = u64_to_user_ptr(info.jited_prog_insns); 2374 ulen = min_t(u32, info.jited_prog_len, ulen); 2375 2376 /* for multi-function programs, copy the JITed 2377 * instructions for all the functions 2378 */ 2379 if (prog->aux->func_cnt) { 2380 u32 len, free, i; 2381 u8 *img; 2382 2383 free = ulen; 2384 for (i = 0; i < prog->aux->func_cnt; i++) { 2385 len = prog->aux->func[i]->jited_len; 2386 len = min_t(u32, len, free); 2387 img = (u8 *) prog->aux->func[i]->bpf_func; 2388 if (copy_to_user(uinsns, img, len)) 2389 return -EFAULT; 2390 uinsns += len; 2391 free -= len; 2392 if (!free) 2393 break; 2394 } 2395 } else { 2396 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 2397 return -EFAULT; 2398 } 2399 } else { 2400 info.jited_prog_insns = 0; 2401 } 2402 } 2403 2404 ulen = info.nr_jited_ksyms; 2405 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 2406 if (ulen) { 2407 if (bpf_dump_raw_ok()) { 2408 unsigned long ksym_addr; 2409 u64 __user *user_ksyms; 2410 u32 i; 2411 2412 /* copy the address of the kernel symbol 2413 * corresponding to each function 2414 */ 2415 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 2416 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 2417 if (prog->aux->func_cnt) { 2418 for (i = 0; i < ulen; i++) { 2419 ksym_addr = (unsigned long) 2420 prog->aux->func[i]->bpf_func; 2421 if (put_user((u64) ksym_addr, 2422 &user_ksyms[i])) 2423 return -EFAULT; 2424 } 2425 } else { 2426 ksym_addr = (unsigned long) prog->bpf_func; 2427 if (put_user((u64) ksym_addr, &user_ksyms[0])) 2428 return -EFAULT; 2429 } 2430 } else { 2431 info.jited_ksyms = 0; 2432 } 2433 } 2434 2435 ulen = info.nr_jited_func_lens; 2436 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 2437 if (ulen) { 2438 if (bpf_dump_raw_ok()) { 2439 u32 __user *user_lens; 2440 u32 func_len, i; 2441 2442 /* copy the JITed image lengths for each function */ 2443 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 2444 user_lens = u64_to_user_ptr(info.jited_func_lens); 2445 if (prog->aux->func_cnt) { 2446 for (i = 0; i < ulen; i++) { 2447 func_len = 2448 prog->aux->func[i]->jited_len; 2449 if (put_user(func_len, &user_lens[i])) 2450 return -EFAULT; 2451 } 2452 } else { 2453 func_len = prog->jited_len; 2454 if (put_user(func_len, &user_lens[0])) 2455 return -EFAULT; 2456 } 2457 } else { 2458 info.jited_func_lens = 0; 2459 } 2460 } 2461 2462 if (prog->aux->btf) 2463 info.btf_id = btf_id(prog->aux->btf); 2464 2465 ulen = info.nr_func_info; 2466 info.nr_func_info = prog->aux->func_info_cnt; 2467 if (info.nr_func_info && ulen) { 2468 char __user *user_finfo; 2469 2470 user_finfo = u64_to_user_ptr(info.func_info); 2471 ulen = min_t(u32, info.nr_func_info, ulen); 2472 if (copy_to_user(user_finfo, prog->aux->func_info, 2473 info.func_info_rec_size * ulen)) 2474 return -EFAULT; 2475 } 2476 2477 ulen = info.nr_line_info; 2478 info.nr_line_info = prog->aux->nr_linfo; 2479 if (info.nr_line_info && ulen) { 2480 __u8 __user *user_linfo; 2481 2482 user_linfo = u64_to_user_ptr(info.line_info); 2483 ulen = min_t(u32, info.nr_line_info, ulen); 2484 if (copy_to_user(user_linfo, prog->aux->linfo, 2485 info.line_info_rec_size * ulen)) 2486 return -EFAULT; 2487 } 2488 2489 ulen = info.nr_jited_line_info; 2490 if (prog->aux->jited_linfo) 2491 info.nr_jited_line_info = prog->aux->nr_linfo; 2492 else 2493 info.nr_jited_line_info = 0; 2494 if (info.nr_jited_line_info && ulen) { 2495 if (bpf_dump_raw_ok()) { 2496 __u64 __user *user_linfo; 2497 u32 i; 2498 2499 user_linfo = u64_to_user_ptr(info.jited_line_info); 2500 ulen = min_t(u32, info.nr_jited_line_info, ulen); 2501 for (i = 0; i < ulen; i++) { 2502 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 2503 &user_linfo[i])) 2504 return -EFAULT; 2505 } 2506 } else { 2507 info.jited_line_info = 0; 2508 } 2509 } 2510 2511 ulen = info.nr_prog_tags; 2512 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 2513 if (ulen) { 2514 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 2515 u32 i; 2516 2517 user_prog_tags = u64_to_user_ptr(info.prog_tags); 2518 ulen = min_t(u32, info.nr_prog_tags, ulen); 2519 if (prog->aux->func_cnt) { 2520 for (i = 0; i < ulen; i++) { 2521 if (copy_to_user(user_prog_tags[i], 2522 prog->aux->func[i]->tag, 2523 BPF_TAG_SIZE)) 2524 return -EFAULT; 2525 } 2526 } else { 2527 if (copy_to_user(user_prog_tags[0], 2528 prog->tag, BPF_TAG_SIZE)) 2529 return -EFAULT; 2530 } 2531 } 2532 2533 done: 2534 if (copy_to_user(uinfo, &info, info_len) || 2535 put_user(info_len, &uattr->info.info_len)) 2536 return -EFAULT; 2537 2538 return 0; 2539 } 2540 2541 static int bpf_map_get_info_by_fd(struct bpf_map *map, 2542 const union bpf_attr *attr, 2543 union bpf_attr __user *uattr) 2544 { 2545 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2546 struct bpf_map_info info = {}; 2547 u32 info_len = attr->info.info_len; 2548 int err; 2549 2550 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2551 if (err) 2552 return err; 2553 info_len = min_t(u32, sizeof(info), info_len); 2554 2555 info.type = map->map_type; 2556 info.id = map->id; 2557 info.key_size = map->key_size; 2558 info.value_size = map->value_size; 2559 info.max_entries = map->max_entries; 2560 info.map_flags = map->map_flags; 2561 memcpy(info.name, map->name, sizeof(map->name)); 2562 2563 if (map->btf) { 2564 info.btf_id = btf_id(map->btf); 2565 info.btf_key_type_id = map->btf_key_type_id; 2566 info.btf_value_type_id = map->btf_value_type_id; 2567 } 2568 2569 if (bpf_map_is_dev_bound(map)) { 2570 err = bpf_map_offload_info_fill(&info, map); 2571 if (err) 2572 return err; 2573 } 2574 2575 if (copy_to_user(uinfo, &info, info_len) || 2576 put_user(info_len, &uattr->info.info_len)) 2577 return -EFAULT; 2578 2579 return 0; 2580 } 2581 2582 static int bpf_btf_get_info_by_fd(struct btf *btf, 2583 const union bpf_attr *attr, 2584 union bpf_attr __user *uattr) 2585 { 2586 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2587 u32 info_len = attr->info.info_len; 2588 int err; 2589 2590 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 2591 if (err) 2592 return err; 2593 2594 return btf_get_info_by_fd(btf, attr, uattr); 2595 } 2596 2597 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 2598 2599 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 2600 union bpf_attr __user *uattr) 2601 { 2602 int ufd = attr->info.bpf_fd; 2603 struct fd f; 2604 int err; 2605 2606 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 2607 return -EINVAL; 2608 2609 f = fdget(ufd); 2610 if (!f.file) 2611 return -EBADFD; 2612 2613 if (f.file->f_op == &bpf_prog_fops) 2614 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 2615 uattr); 2616 else if (f.file->f_op == &bpf_map_fops) 2617 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 2618 uattr); 2619 else if (f.file->f_op == &btf_fops) 2620 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 2621 else 2622 err = -EINVAL; 2623 2624 fdput(f); 2625 return err; 2626 } 2627 2628 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 2629 2630 static int bpf_btf_load(const union bpf_attr *attr) 2631 { 2632 if (CHECK_ATTR(BPF_BTF_LOAD)) 2633 return -EINVAL; 2634 2635 if (!capable(CAP_SYS_ADMIN)) 2636 return -EPERM; 2637 2638 return btf_new_fd(attr); 2639 } 2640 2641 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 2642 2643 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 2644 { 2645 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 2646 return -EINVAL; 2647 2648 if (!capable(CAP_SYS_ADMIN)) 2649 return -EPERM; 2650 2651 return btf_get_fd_by_id(attr->btf_id); 2652 } 2653 2654 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 2655 union bpf_attr __user *uattr, 2656 u32 prog_id, u32 fd_type, 2657 const char *buf, u64 probe_offset, 2658 u64 probe_addr) 2659 { 2660 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 2661 u32 len = buf ? strlen(buf) : 0, input_len; 2662 int err = 0; 2663 2664 if (put_user(len, &uattr->task_fd_query.buf_len)) 2665 return -EFAULT; 2666 input_len = attr->task_fd_query.buf_len; 2667 if (input_len && ubuf) { 2668 if (!len) { 2669 /* nothing to copy, just make ubuf NULL terminated */ 2670 char zero = '\0'; 2671 2672 if (put_user(zero, ubuf)) 2673 return -EFAULT; 2674 } else if (input_len >= len + 1) { 2675 /* ubuf can hold the string with NULL terminator */ 2676 if (copy_to_user(ubuf, buf, len + 1)) 2677 return -EFAULT; 2678 } else { 2679 /* ubuf cannot hold the string with NULL terminator, 2680 * do a partial copy with NULL terminator. 2681 */ 2682 char zero = '\0'; 2683 2684 err = -ENOSPC; 2685 if (copy_to_user(ubuf, buf, input_len - 1)) 2686 return -EFAULT; 2687 if (put_user(zero, ubuf + input_len - 1)) 2688 return -EFAULT; 2689 } 2690 } 2691 2692 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 2693 put_user(fd_type, &uattr->task_fd_query.fd_type) || 2694 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 2695 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 2696 return -EFAULT; 2697 2698 return err; 2699 } 2700 2701 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 2702 2703 static int bpf_task_fd_query(const union bpf_attr *attr, 2704 union bpf_attr __user *uattr) 2705 { 2706 pid_t pid = attr->task_fd_query.pid; 2707 u32 fd = attr->task_fd_query.fd; 2708 const struct perf_event *event; 2709 struct files_struct *files; 2710 struct task_struct *task; 2711 struct file *file; 2712 int err; 2713 2714 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 2715 return -EINVAL; 2716 2717 if (!capable(CAP_SYS_ADMIN)) 2718 return -EPERM; 2719 2720 if (attr->task_fd_query.flags != 0) 2721 return -EINVAL; 2722 2723 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 2724 if (!task) 2725 return -ENOENT; 2726 2727 files = get_files_struct(task); 2728 put_task_struct(task); 2729 if (!files) 2730 return -ENOENT; 2731 2732 err = 0; 2733 spin_lock(&files->file_lock); 2734 file = fcheck_files(files, fd); 2735 if (!file) 2736 err = -EBADF; 2737 else 2738 get_file(file); 2739 spin_unlock(&files->file_lock); 2740 put_files_struct(files); 2741 2742 if (err) 2743 goto out; 2744 2745 if (file->f_op == &bpf_raw_tp_fops) { 2746 struct bpf_raw_tracepoint *raw_tp = file->private_data; 2747 struct bpf_raw_event_map *btp = raw_tp->btp; 2748 2749 err = bpf_task_fd_query_copy(attr, uattr, 2750 raw_tp->prog->aux->id, 2751 BPF_FD_TYPE_RAW_TRACEPOINT, 2752 btp->tp->name, 0, 0); 2753 goto put_file; 2754 } 2755 2756 event = perf_get_event(file); 2757 if (!IS_ERR(event)) { 2758 u64 probe_offset, probe_addr; 2759 u32 prog_id, fd_type; 2760 const char *buf; 2761 2762 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 2763 &buf, &probe_offset, 2764 &probe_addr); 2765 if (!err) 2766 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 2767 fd_type, buf, 2768 probe_offset, 2769 probe_addr); 2770 goto put_file; 2771 } 2772 2773 err = -ENOTSUPP; 2774 put_file: 2775 fput(file); 2776 out: 2777 return err; 2778 } 2779 2780 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 2781 { 2782 union bpf_attr attr = {}; 2783 int err; 2784 2785 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 2786 return -EPERM; 2787 2788 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 2789 if (err) 2790 return err; 2791 size = min_t(u32, size, sizeof(attr)); 2792 2793 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 2794 if (copy_from_user(&attr, uattr, size) != 0) 2795 return -EFAULT; 2796 2797 err = security_bpf(cmd, &attr, size); 2798 if (err < 0) 2799 return err; 2800 2801 switch (cmd) { 2802 case BPF_MAP_CREATE: 2803 err = map_create(&attr); 2804 break; 2805 case BPF_MAP_LOOKUP_ELEM: 2806 err = map_lookup_elem(&attr); 2807 break; 2808 case BPF_MAP_UPDATE_ELEM: 2809 err = map_update_elem(&attr); 2810 break; 2811 case BPF_MAP_DELETE_ELEM: 2812 err = map_delete_elem(&attr); 2813 break; 2814 case BPF_MAP_GET_NEXT_KEY: 2815 err = map_get_next_key(&attr); 2816 break; 2817 case BPF_MAP_FREEZE: 2818 err = map_freeze(&attr); 2819 break; 2820 case BPF_PROG_LOAD: 2821 err = bpf_prog_load(&attr, uattr); 2822 break; 2823 case BPF_OBJ_PIN: 2824 err = bpf_obj_pin(&attr); 2825 break; 2826 case BPF_OBJ_GET: 2827 err = bpf_obj_get(&attr); 2828 break; 2829 case BPF_PROG_ATTACH: 2830 err = bpf_prog_attach(&attr); 2831 break; 2832 case BPF_PROG_DETACH: 2833 err = bpf_prog_detach(&attr); 2834 break; 2835 case BPF_PROG_QUERY: 2836 err = bpf_prog_query(&attr, uattr); 2837 break; 2838 case BPF_PROG_TEST_RUN: 2839 err = bpf_prog_test_run(&attr, uattr); 2840 break; 2841 case BPF_PROG_GET_NEXT_ID: 2842 err = bpf_obj_get_next_id(&attr, uattr, 2843 &prog_idr, &prog_idr_lock); 2844 break; 2845 case BPF_MAP_GET_NEXT_ID: 2846 err = bpf_obj_get_next_id(&attr, uattr, 2847 &map_idr, &map_idr_lock); 2848 break; 2849 case BPF_PROG_GET_FD_BY_ID: 2850 err = bpf_prog_get_fd_by_id(&attr); 2851 break; 2852 case BPF_MAP_GET_FD_BY_ID: 2853 err = bpf_map_get_fd_by_id(&attr); 2854 break; 2855 case BPF_OBJ_GET_INFO_BY_FD: 2856 err = bpf_obj_get_info_by_fd(&attr, uattr); 2857 break; 2858 case BPF_RAW_TRACEPOINT_OPEN: 2859 err = bpf_raw_tracepoint_open(&attr); 2860 break; 2861 case BPF_BTF_LOAD: 2862 err = bpf_btf_load(&attr); 2863 break; 2864 case BPF_BTF_GET_FD_BY_ID: 2865 err = bpf_btf_get_fd_by_id(&attr); 2866 break; 2867 case BPF_TASK_FD_QUERY: 2868 err = bpf_task_fd_query(&attr, uattr); 2869 break; 2870 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 2871 err = map_lookup_and_delete_elem(&attr); 2872 break; 2873 default: 2874 err = -EINVAL; 2875 break; 2876 } 2877 2878 return err; 2879 } 2880