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