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