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