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