1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf_trace.h> 6 #include <linux/bpf_lirc.h> 7 #include <linux/btf.h> 8 #include <linux/syscalls.h> 9 #include <linux/slab.h> 10 #include <linux/sched/signal.h> 11 #include <linux/vmalloc.h> 12 #include <linux/mmzone.h> 13 #include <linux/anon_inodes.h> 14 #include <linux/fdtable.h> 15 #include <linux/file.h> 16 #include <linux/fs.h> 17 #include <linux/license.h> 18 #include <linux/filter.h> 19 #include <linux/version.h> 20 #include <linux/kernel.h> 21 #include <linux/idr.h> 22 #include <linux/cred.h> 23 #include <linux/timekeeping.h> 24 #include <linux/ctype.h> 25 #include <linux/nospec.h> 26 #include <uapi/linux/btf.h> 27 28 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \ 29 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 30 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 31 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 32 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 33 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map)) 34 35 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 36 37 DEFINE_PER_CPU(int, bpf_prog_active); 38 static DEFINE_IDR(prog_idr); 39 static DEFINE_SPINLOCK(prog_idr_lock); 40 static DEFINE_IDR(map_idr); 41 static DEFINE_SPINLOCK(map_idr_lock); 42 43 int sysctl_unprivileged_bpf_disabled __read_mostly; 44 45 static const struct bpf_map_ops * const bpf_map_types[] = { 46 #define BPF_PROG_TYPE(_id, _ops) 47 #define BPF_MAP_TYPE(_id, _ops) \ 48 [_id] = &_ops, 49 #include <linux/bpf_types.h> 50 #undef BPF_PROG_TYPE 51 #undef BPF_MAP_TYPE 52 }; 53 54 /* 55 * If we're handed a bigger struct than we know of, ensure all the unknown bits 56 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 57 * we don't know about yet. 58 * 59 * There is a ToCToU between this function call and the following 60 * copy_from_user() call. However, this is not a concern since this function is 61 * meant to be a future-proofing of bits. 62 */ 63 int bpf_check_uarg_tail_zero(void __user *uaddr, 64 size_t expected_size, 65 size_t actual_size) 66 { 67 unsigned char __user *addr; 68 unsigned char __user *end; 69 unsigned char val; 70 int err; 71 72 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 73 return -E2BIG; 74 75 if (unlikely(!access_ok(uaddr, actual_size))) 76 return -EFAULT; 77 78 if (actual_size <= expected_size) 79 return 0; 80 81 addr = uaddr + expected_size; 82 end = uaddr + actual_size; 83 84 for (; addr < end; addr++) { 85 err = get_user(val, addr); 86 if (err) 87 return err; 88 if (val) 89 return -E2BIG; 90 } 91 92 return 0; 93 } 94 95 const struct bpf_map_ops bpf_map_offload_ops = { 96 .map_alloc = bpf_map_offload_map_alloc, 97 .map_free = bpf_map_offload_map_free, 98 .map_check_btf = map_check_no_btf, 99 }; 100 101 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 102 { 103 const struct bpf_map_ops *ops; 104 u32 type = attr->map_type; 105 struct bpf_map *map; 106 int err; 107 108 if (type >= ARRAY_SIZE(bpf_map_types)) 109 return ERR_PTR(-EINVAL); 110 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 111 ops = bpf_map_types[type]; 112 if (!ops) 113 return ERR_PTR(-EINVAL); 114 115 if (ops->map_alloc_check) { 116 err = ops->map_alloc_check(attr); 117 if (err) 118 return ERR_PTR(err); 119 } 120 if (attr->map_ifindex) 121 ops = &bpf_map_offload_ops; 122 map = ops->map_alloc(attr); 123 if (IS_ERR(map)) 124 return map; 125 map->ops = ops; 126 map->map_type = type; 127 return map; 128 } 129 130 void *bpf_map_area_alloc(size_t size, int numa_node) 131 { 132 /* We really just want to fail instead of triggering OOM killer 133 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 134 * which is used for lower order allocation requests. 135 * 136 * It has been observed that higher order allocation requests done by 137 * vmalloc with __GFP_NORETRY being set might fail due to not trying 138 * to reclaim memory from the page cache, thus we set 139 * __GFP_RETRY_MAYFAIL to avoid such situations. 140 */ 141 142 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; 143 void *area; 144 145 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 146 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, 147 numa_node); 148 if (area != NULL) 149 return area; 150 } 151 152 return __vmalloc_node_flags_caller(size, numa_node, 153 GFP_KERNEL | __GFP_RETRY_MAYFAIL | 154 flags, __builtin_return_address(0)); 155 } 156 157 void bpf_map_area_free(void *area) 158 { 159 kvfree(area); 160 } 161 162 static u32 bpf_map_flags_retain_permanent(u32 flags) 163 { 164 /* Some map creation flags are not tied to the map object but 165 * rather to the map fd instead, so they have no meaning upon 166 * map object inspection since multiple file descriptors with 167 * different (access) properties can exist here. Thus, given 168 * this has zero meaning for the map itself, lets clear these 169 * from here. 170 */ 171 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 172 } 173 174 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 175 { 176 map->map_type = attr->map_type; 177 map->key_size = attr->key_size; 178 map->value_size = attr->value_size; 179 map->max_entries = attr->max_entries; 180 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 181 map->numa_node = bpf_map_attr_numa_node(attr); 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 if (user) 198 atomic_long_sub(pages, &user->locked_vm); 199 } 200 201 int bpf_map_charge_init(struct bpf_map_memory *mem, size_t size) 202 { 203 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT; 204 struct user_struct *user; 205 int ret; 206 207 if (size >= U32_MAX - PAGE_SIZE) 208 return -E2BIG; 209 210 user = get_current_user(); 211 ret = bpf_charge_memlock(user, pages); 212 if (ret) { 213 free_uid(user); 214 return ret; 215 } 216 217 mem->pages = pages; 218 mem->user = user; 219 220 return 0; 221 } 222 223 void bpf_map_charge_finish(struct bpf_map_memory *mem) 224 { 225 bpf_uncharge_memlock(mem->user, mem->pages); 226 free_uid(mem->user); 227 } 228 229 void bpf_map_charge_move(struct bpf_map_memory *dst, 230 struct bpf_map_memory *src) 231 { 232 *dst = *src; 233 234 /* Make sure src will not be used for the redundant uncharging. */ 235 memset(src, 0, sizeof(struct bpf_map_memory)); 236 } 237 238 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages) 239 { 240 int ret; 241 242 ret = bpf_charge_memlock(map->memory.user, pages); 243 if (ret) 244 return ret; 245 map->memory.pages += pages; 246 return ret; 247 } 248 249 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages) 250 { 251 bpf_uncharge_memlock(map->memory.user, pages); 252 map->memory.pages -= pages; 253 } 254 255 static int bpf_map_alloc_id(struct bpf_map *map) 256 { 257 int id; 258 259 idr_preload(GFP_KERNEL); 260 spin_lock_bh(&map_idr_lock); 261 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 262 if (id > 0) 263 map->id = id; 264 spin_unlock_bh(&map_idr_lock); 265 idr_preload_end(); 266 267 if (WARN_ON_ONCE(!id)) 268 return -ENOSPC; 269 270 return id > 0 ? 0 : id; 271 } 272 273 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 274 { 275 unsigned long flags; 276 277 /* Offloaded maps are removed from the IDR store when their device 278 * disappears - even if someone holds an fd to them they are unusable, 279 * the memory is gone, all ops will fail; they are simply waiting for 280 * refcnt to drop to be freed. 281 */ 282 if (!map->id) 283 return; 284 285 if (do_idr_lock) 286 spin_lock_irqsave(&map_idr_lock, flags); 287 else 288 __acquire(&map_idr_lock); 289 290 idr_remove(&map_idr, map->id); 291 map->id = 0; 292 293 if (do_idr_lock) 294 spin_unlock_irqrestore(&map_idr_lock, flags); 295 else 296 __release(&map_idr_lock); 297 } 298 299 /* called from workqueue */ 300 static void bpf_map_free_deferred(struct work_struct *work) 301 { 302 struct bpf_map *map = container_of(work, struct bpf_map, work); 303 struct bpf_map_memory mem; 304 305 bpf_map_charge_move(&mem, &map->memory); 306 security_bpf_map_free(map); 307 /* implementation dependent freeing */ 308 map->ops->map_free(map); 309 bpf_map_charge_finish(&mem); 310 } 311 312 static void bpf_map_put_uref(struct bpf_map *map) 313 { 314 if (atomic_dec_and_test(&map->usercnt)) { 315 if (map->ops->map_release_uref) 316 map->ops->map_release_uref(map); 317 } 318 } 319 320 /* decrement map refcnt and schedule it for freeing via workqueue 321 * (unrelying map implementation ops->map_free() might sleep) 322 */ 323 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 324 { 325 if (atomic_dec_and_test(&map->refcnt)) { 326 /* bpf_map_free_id() must be called first */ 327 bpf_map_free_id(map, do_idr_lock); 328 btf_put(map->btf); 329 INIT_WORK(&map->work, bpf_map_free_deferred); 330 schedule_work(&map->work); 331 } 332 } 333 334 void bpf_map_put(struct bpf_map *map) 335 { 336 __bpf_map_put(map, true); 337 } 338 EXPORT_SYMBOL_GPL(bpf_map_put); 339 340 void bpf_map_put_with_uref(struct bpf_map *map) 341 { 342 bpf_map_put_uref(map); 343 bpf_map_put(map); 344 } 345 346 static int bpf_map_release(struct inode *inode, struct file *filp) 347 { 348 struct bpf_map *map = filp->private_data; 349 350 if (map->ops->map_release) 351 map->ops->map_release(map, filp); 352 353 bpf_map_put_with_uref(map); 354 return 0; 355 } 356 357 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 358 { 359 fmode_t mode = f.file->f_mode; 360 361 /* Our file permissions may have been overridden by global 362 * map permissions facing syscall side. 363 */ 364 if (READ_ONCE(map->frozen)) 365 mode &= ~FMODE_CAN_WRITE; 366 return mode; 367 } 368 369 #ifdef CONFIG_PROC_FS 370 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 371 { 372 const struct bpf_map *map = filp->private_data; 373 const struct bpf_array *array; 374 u32 owner_prog_type = 0; 375 u32 owner_jited = 0; 376 377 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 378 array = container_of(map, struct bpf_array, map); 379 owner_prog_type = array->owner_prog_type; 380 owner_jited = array->owner_jited; 381 } 382 383 seq_printf(m, 384 "map_type:\t%u\n" 385 "key_size:\t%u\n" 386 "value_size:\t%u\n" 387 "max_entries:\t%u\n" 388 "map_flags:\t%#x\n" 389 "memlock:\t%llu\n" 390 "map_id:\t%u\n" 391 "frozen:\t%u\n", 392 map->map_type, 393 map->key_size, 394 map->value_size, 395 map->max_entries, 396 map->map_flags, 397 map->memory.pages * 1ULL << PAGE_SHIFT, 398 map->id, 399 READ_ONCE(map->frozen)); 400 401 if (owner_prog_type) { 402 seq_printf(m, "owner_prog_type:\t%u\n", 403 owner_prog_type); 404 seq_printf(m, "owner_jited:\t%u\n", 405 owner_jited); 406 } 407 } 408 #endif 409 410 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 411 loff_t *ppos) 412 { 413 /* We need this handler such that alloc_file() enables 414 * f_mode with FMODE_CAN_READ. 415 */ 416 return -EINVAL; 417 } 418 419 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 420 size_t siz, loff_t *ppos) 421 { 422 /* We need this handler such that alloc_file() enables 423 * f_mode with FMODE_CAN_WRITE. 424 */ 425 return -EINVAL; 426 } 427 428 const struct file_operations bpf_map_fops = { 429 #ifdef CONFIG_PROC_FS 430 .show_fdinfo = bpf_map_show_fdinfo, 431 #endif 432 .release = bpf_map_release, 433 .read = bpf_dummy_read, 434 .write = bpf_dummy_write, 435 }; 436 437 int bpf_map_new_fd(struct bpf_map *map, int flags) 438 { 439 int ret; 440 441 ret = security_bpf_map(map, OPEN_FMODE(flags)); 442 if (ret < 0) 443 return ret; 444 445 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 446 flags | O_CLOEXEC); 447 } 448 449 int bpf_get_file_flag(int flags) 450 { 451 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 452 return -EINVAL; 453 if (flags & BPF_F_RDONLY) 454 return O_RDONLY; 455 if (flags & BPF_F_WRONLY) 456 return O_WRONLY; 457 return O_RDWR; 458 } 459 460 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 461 #define CHECK_ATTR(CMD) \ 462 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 463 sizeof(attr->CMD##_LAST_FIELD), 0, \ 464 sizeof(*attr) - \ 465 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 466 sizeof(attr->CMD##_LAST_FIELD)) != NULL 467 468 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes. 469 * Return 0 on success and < 0 on error. 470 */ 471 static int bpf_obj_name_cpy(char *dst, const char *src) 472 { 473 const char *end = src + BPF_OBJ_NAME_LEN; 474 475 memset(dst, 0, BPF_OBJ_NAME_LEN); 476 /* Copy all isalnum(), '_' and '.' chars. */ 477 while (src < end && *src) { 478 if (!isalnum(*src) && 479 *src != '_' && *src != '.') 480 return -EINVAL; 481 *dst++ = *src++; 482 } 483 484 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */ 485 if (src == end) 486 return -EINVAL; 487 488 return 0; 489 } 490 491 int map_check_no_btf(const struct bpf_map *map, 492 const struct btf *btf, 493 const struct btf_type *key_type, 494 const struct btf_type *value_type) 495 { 496 return -ENOTSUPP; 497 } 498 499 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 500 u32 btf_key_id, u32 btf_value_id) 501 { 502 const struct btf_type *key_type, *value_type; 503 u32 key_size, value_size; 504 int ret = 0; 505 506 /* Some maps allow key to be unspecified. */ 507 if (btf_key_id) { 508 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 509 if (!key_type || key_size != map->key_size) 510 return -EINVAL; 511 } else { 512 key_type = btf_type_by_id(btf, 0); 513 if (!map->ops->map_check_btf) 514 return -EINVAL; 515 } 516 517 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 518 if (!value_type || value_size != map->value_size) 519 return -EINVAL; 520 521 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 522 523 if (map_value_has_spin_lock(map)) { 524 if (map->map_flags & BPF_F_RDONLY_PROG) 525 return -EACCES; 526 if (map->map_type != BPF_MAP_TYPE_HASH && 527 map->map_type != BPF_MAP_TYPE_ARRAY && 528 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 529 map->map_type != BPF_MAP_TYPE_SK_STORAGE) 530 return -ENOTSUPP; 531 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 532 map->value_size) { 533 WARN_ONCE(1, 534 "verifier bug spin_lock_off %d value_size %d\n", 535 map->spin_lock_off, map->value_size); 536 return -EFAULT; 537 } 538 } 539 540 if (map->ops->map_check_btf) 541 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 542 543 return ret; 544 } 545 546 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id 547 /* called via syscall */ 548 static int map_create(union bpf_attr *attr) 549 { 550 int numa_node = bpf_map_attr_numa_node(attr); 551 struct bpf_map_memory mem; 552 struct bpf_map *map; 553 int f_flags; 554 int err; 555 556 err = CHECK_ATTR(BPF_MAP_CREATE); 557 if (err) 558 return -EINVAL; 559 560 f_flags = bpf_get_file_flag(attr->map_flags); 561 if (f_flags < 0) 562 return f_flags; 563 564 if (numa_node != NUMA_NO_NODE && 565 ((unsigned int)numa_node >= nr_node_ids || 566 !node_online(numa_node))) 567 return -EINVAL; 568 569 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 570 map = find_and_alloc_map(attr); 571 if (IS_ERR(map)) 572 return PTR_ERR(map); 573 574 err = bpf_obj_name_cpy(map->name, attr->map_name); 575 if (err) 576 goto free_map; 577 578 atomic_set(&map->refcnt, 1); 579 atomic_set(&map->usercnt, 1); 580 581 if (attr->btf_key_type_id || attr->btf_value_type_id) { 582 struct btf *btf; 583 584 if (!attr->btf_value_type_id) { 585 err = -EINVAL; 586 goto free_map; 587 } 588 589 btf = btf_get_by_fd(attr->btf_fd); 590 if (IS_ERR(btf)) { 591 err = PTR_ERR(btf); 592 goto free_map; 593 } 594 595 err = map_check_btf(map, btf, attr->btf_key_type_id, 596 attr->btf_value_type_id); 597 if (err) { 598 btf_put(btf); 599 goto free_map; 600 } 601 602 map->btf = btf; 603 map->btf_key_type_id = attr->btf_key_type_id; 604 map->btf_value_type_id = attr->btf_value_type_id; 605 } else { 606 map->spin_lock_off = -EINVAL; 607 } 608 609 err = security_bpf_map_alloc(map); 610 if (err) 611 goto free_map; 612 613 err = bpf_map_alloc_id(map); 614 if (err) 615 goto free_map_sec; 616 617 err = bpf_map_new_fd(map, f_flags); 618 if (err < 0) { 619 /* failed to allocate fd. 620 * bpf_map_put_with_uref() is needed because the above 621 * bpf_map_alloc_id() has published the map 622 * to the userspace and the userspace may 623 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 624 */ 625 bpf_map_put_with_uref(map); 626 return err; 627 } 628 629 return err; 630 631 free_map_sec: 632 security_bpf_map_free(map); 633 free_map: 634 btf_put(map->btf); 635 bpf_map_charge_move(&mem, &map->memory); 636 map->ops->map_free(map); 637 bpf_map_charge_finish(&mem); 638 return err; 639 } 640 641 /* if error is returned, fd is released. 642 * On success caller should complete fd access with matching fdput() 643 */ 644 struct bpf_map *__bpf_map_get(struct fd f) 645 { 646 if (!f.file) 647 return ERR_PTR(-EBADF); 648 if (f.file->f_op != &bpf_map_fops) { 649 fdput(f); 650 return ERR_PTR(-EINVAL); 651 } 652 653 return f.file->private_data; 654 } 655 656 /* prog's and map's refcnt limit */ 657 #define BPF_MAX_REFCNT 32768 658 659 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) 660 { 661 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { 662 atomic_dec(&map->refcnt); 663 return ERR_PTR(-EBUSY); 664 } 665 if (uref) 666 atomic_inc(&map->usercnt); 667 return map; 668 } 669 EXPORT_SYMBOL_GPL(bpf_map_inc); 670 671 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 672 { 673 struct fd f = fdget(ufd); 674 struct bpf_map *map; 675 676 map = __bpf_map_get(f); 677 if (IS_ERR(map)) 678 return map; 679 680 map = bpf_map_inc(map, true); 681 fdput(f); 682 683 return map; 684 } 685 686 /* map_idr_lock should have been held */ 687 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, 688 bool uref) 689 { 690 int refold; 691 692 refold = atomic_fetch_add_unless(&map->refcnt, 1, 0); 693 694 if (refold >= BPF_MAX_REFCNT) { 695 __bpf_map_put(map, false); 696 return ERR_PTR(-EBUSY); 697 } 698 699 if (!refold) 700 return ERR_PTR(-ENOENT); 701 702 if (uref) 703 atomic_inc(&map->usercnt); 704 705 return map; 706 } 707 708 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 709 { 710 spin_lock_bh(&map_idr_lock); 711 map = __bpf_map_inc_not_zero(map, uref); 712 spin_unlock_bh(&map_idr_lock); 713 714 return map; 715 } 716 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 717 718 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 719 { 720 return -ENOTSUPP; 721 } 722 723 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 724 { 725 if (key_size) 726 return memdup_user(ukey, key_size); 727 728 if (ukey) 729 return ERR_PTR(-EINVAL); 730 731 return NULL; 732 } 733 734 /* last field in 'union bpf_attr' used by this command */ 735 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 736 737 static int map_lookup_elem(union bpf_attr *attr) 738 { 739 void __user *ukey = u64_to_user_ptr(attr->key); 740 void __user *uvalue = u64_to_user_ptr(attr->value); 741 int ufd = attr->map_fd; 742 struct bpf_map *map; 743 void *key, *value, *ptr; 744 u32 value_size; 745 struct fd f; 746 int err; 747 748 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 749 return -EINVAL; 750 751 if (attr->flags & ~BPF_F_LOCK) 752 return -EINVAL; 753 754 f = fdget(ufd); 755 map = __bpf_map_get(f); 756 if (IS_ERR(map)) 757 return PTR_ERR(map); 758 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 759 err = -EPERM; 760 goto err_put; 761 } 762 763 if ((attr->flags & BPF_F_LOCK) && 764 !map_value_has_spin_lock(map)) { 765 err = -EINVAL; 766 goto err_put; 767 } 768 769 key = __bpf_copy_key(ukey, map->key_size); 770 if (IS_ERR(key)) { 771 err = PTR_ERR(key); 772 goto err_put; 773 } 774 775 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 776 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 777 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 778 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 779 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 780 else if (IS_FD_MAP(map)) 781 value_size = sizeof(u32); 782 else 783 value_size = map->value_size; 784 785 err = -ENOMEM; 786 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 787 if (!value) 788 goto free_key; 789 790 if (bpf_map_is_dev_bound(map)) { 791 err = bpf_map_offload_lookup_elem(map, key, value); 792 goto done; 793 } 794 795 preempt_disable(); 796 this_cpu_inc(bpf_prog_active); 797 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 798 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 799 err = bpf_percpu_hash_copy(map, key, value); 800 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 801 err = bpf_percpu_array_copy(map, key, value); 802 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 803 err = bpf_percpu_cgroup_storage_copy(map, key, value); 804 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 805 err = bpf_stackmap_copy(map, key, value); 806 } else if (IS_FD_ARRAY(map)) { 807 err = bpf_fd_array_map_lookup_elem(map, key, value); 808 } else if (IS_FD_HASH(map)) { 809 err = bpf_fd_htab_map_lookup_elem(map, key, value); 810 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 811 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 812 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 813 map->map_type == BPF_MAP_TYPE_STACK) { 814 err = map->ops->map_peek_elem(map, value); 815 } else { 816 rcu_read_lock(); 817 if (map->ops->map_lookup_elem_sys_only) 818 ptr = map->ops->map_lookup_elem_sys_only(map, key); 819 else 820 ptr = map->ops->map_lookup_elem(map, key); 821 if (IS_ERR(ptr)) { 822 err = PTR_ERR(ptr); 823 } else if (!ptr) { 824 err = -ENOENT; 825 } else { 826 err = 0; 827 if (attr->flags & BPF_F_LOCK) 828 /* lock 'ptr' and copy everything but lock */ 829 copy_map_value_locked(map, value, ptr, true); 830 else 831 copy_map_value(map, value, ptr); 832 /* mask lock, since value wasn't zero inited */ 833 check_and_init_map_lock(map, value); 834 } 835 rcu_read_unlock(); 836 } 837 this_cpu_dec(bpf_prog_active); 838 preempt_enable(); 839 840 done: 841 if (err) 842 goto free_value; 843 844 err = -EFAULT; 845 if (copy_to_user(uvalue, value, value_size) != 0) 846 goto free_value; 847 848 err = 0; 849 850 free_value: 851 kfree(value); 852 free_key: 853 kfree(key); 854 err_put: 855 fdput(f); 856 return err; 857 } 858 859 static void maybe_wait_bpf_programs(struct bpf_map *map) 860 { 861 /* Wait for any running BPF programs to complete so that 862 * userspace, when we return to it, knows that all programs 863 * that could be running use the new map value. 864 */ 865 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 866 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 867 synchronize_rcu(); 868 } 869 870 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 871 872 static int map_update_elem(union bpf_attr *attr) 873 { 874 void __user *ukey = u64_to_user_ptr(attr->key); 875 void __user *uvalue = u64_to_user_ptr(attr->value); 876 int ufd = attr->map_fd; 877 struct bpf_map *map; 878 void *key, *value; 879 u32 value_size; 880 struct fd f; 881 int err; 882 883 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 884 return -EINVAL; 885 886 f = fdget(ufd); 887 map = __bpf_map_get(f); 888 if (IS_ERR(map)) 889 return PTR_ERR(map); 890 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 891 err = -EPERM; 892 goto err_put; 893 } 894 895 if ((attr->flags & BPF_F_LOCK) && 896 !map_value_has_spin_lock(map)) { 897 err = -EINVAL; 898 goto err_put; 899 } 900 901 key = __bpf_copy_key(ukey, map->key_size); 902 if (IS_ERR(key)) { 903 err = PTR_ERR(key); 904 goto err_put; 905 } 906 907 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 908 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 909 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 910 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 911 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 912 else 913 value_size = map->value_size; 914 915 err = -ENOMEM; 916 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 917 if (!value) 918 goto free_key; 919 920 err = -EFAULT; 921 if (copy_from_user(value, uvalue, value_size) != 0) 922 goto free_value; 923 924 /* Need to create a kthread, thus must support schedule */ 925 if (bpf_map_is_dev_bound(map)) { 926 err = bpf_map_offload_update_elem(map, key, value, attr->flags); 927 goto out; 928 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 929 map->map_type == BPF_MAP_TYPE_SOCKHASH || 930 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 931 err = map->ops->map_update_elem(map, key, value, attr->flags); 932 goto out; 933 } 934 935 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from 936 * inside bpf map update or delete otherwise deadlocks are possible 937 */ 938 preempt_disable(); 939 __this_cpu_inc(bpf_prog_active); 940 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 941 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 942 err = bpf_percpu_hash_update(map, key, value, attr->flags); 943 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 944 err = bpf_percpu_array_update(map, key, value, attr->flags); 945 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 946 err = bpf_percpu_cgroup_storage_update(map, key, value, 947 attr->flags); 948 } else if (IS_FD_ARRAY(map)) { 949 rcu_read_lock(); 950 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 951 attr->flags); 952 rcu_read_unlock(); 953 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 954 rcu_read_lock(); 955 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 956 attr->flags); 957 rcu_read_unlock(); 958 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 959 /* rcu_read_lock() is not needed */ 960 err = bpf_fd_reuseport_array_update_elem(map, key, value, 961 attr->flags); 962 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 963 map->map_type == BPF_MAP_TYPE_STACK) { 964 err = map->ops->map_push_elem(map, value, attr->flags); 965 } else { 966 rcu_read_lock(); 967 err = map->ops->map_update_elem(map, key, value, attr->flags); 968 rcu_read_unlock(); 969 } 970 __this_cpu_dec(bpf_prog_active); 971 preempt_enable(); 972 maybe_wait_bpf_programs(map); 973 out: 974 free_value: 975 kfree(value); 976 free_key: 977 kfree(key); 978 err_put: 979 fdput(f); 980 return err; 981 } 982 983 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 984 985 static int map_delete_elem(union bpf_attr *attr) 986 { 987 void __user *ukey = u64_to_user_ptr(attr->key); 988 int ufd = attr->map_fd; 989 struct bpf_map *map; 990 struct fd f; 991 void *key; 992 int err; 993 994 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 995 return -EINVAL; 996 997 f = fdget(ufd); 998 map = __bpf_map_get(f); 999 if (IS_ERR(map)) 1000 return PTR_ERR(map); 1001 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1002 err = -EPERM; 1003 goto err_put; 1004 } 1005 1006 key = __bpf_copy_key(ukey, map->key_size); 1007 if (IS_ERR(key)) { 1008 err = PTR_ERR(key); 1009 goto err_put; 1010 } 1011 1012 if (bpf_map_is_dev_bound(map)) { 1013 err = bpf_map_offload_delete_elem(map, key); 1014 goto out; 1015 } 1016 1017 preempt_disable(); 1018 __this_cpu_inc(bpf_prog_active); 1019 rcu_read_lock(); 1020 err = map->ops->map_delete_elem(map, key); 1021 rcu_read_unlock(); 1022 __this_cpu_dec(bpf_prog_active); 1023 preempt_enable(); 1024 maybe_wait_bpf_programs(map); 1025 out: 1026 kfree(key); 1027 err_put: 1028 fdput(f); 1029 return err; 1030 } 1031 1032 /* last field in 'union bpf_attr' used by this command */ 1033 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1034 1035 static int map_get_next_key(union bpf_attr *attr) 1036 { 1037 void __user *ukey = u64_to_user_ptr(attr->key); 1038 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1039 int ufd = attr->map_fd; 1040 struct bpf_map *map; 1041 void *key, *next_key; 1042 struct fd f; 1043 int err; 1044 1045 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1046 return -EINVAL; 1047 1048 f = fdget(ufd); 1049 map = __bpf_map_get(f); 1050 if (IS_ERR(map)) 1051 return PTR_ERR(map); 1052 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1053 err = -EPERM; 1054 goto err_put; 1055 } 1056 1057 if (ukey) { 1058 key = __bpf_copy_key(ukey, map->key_size); 1059 if (IS_ERR(key)) { 1060 err = PTR_ERR(key); 1061 goto err_put; 1062 } 1063 } else { 1064 key = NULL; 1065 } 1066 1067 err = -ENOMEM; 1068 next_key = kmalloc(map->key_size, GFP_USER); 1069 if (!next_key) 1070 goto free_key; 1071 1072 if (bpf_map_is_dev_bound(map)) { 1073 err = bpf_map_offload_get_next_key(map, key, next_key); 1074 goto out; 1075 } 1076 1077 rcu_read_lock(); 1078 err = map->ops->map_get_next_key(map, key, next_key); 1079 rcu_read_unlock(); 1080 out: 1081 if (err) 1082 goto free_next_key; 1083 1084 err = -EFAULT; 1085 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1086 goto free_next_key; 1087 1088 err = 0; 1089 1090 free_next_key: 1091 kfree(next_key); 1092 free_key: 1093 kfree(key); 1094 err_put: 1095 fdput(f); 1096 return err; 1097 } 1098 1099 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value 1100 1101 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1102 { 1103 void __user *ukey = u64_to_user_ptr(attr->key); 1104 void __user *uvalue = u64_to_user_ptr(attr->value); 1105 int ufd = attr->map_fd; 1106 struct bpf_map *map; 1107 void *key, *value; 1108 u32 value_size; 1109 struct fd f; 1110 int err; 1111 1112 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1113 return -EINVAL; 1114 1115 f = fdget(ufd); 1116 map = __bpf_map_get(f); 1117 if (IS_ERR(map)) 1118 return PTR_ERR(map); 1119 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1120 err = -EPERM; 1121 goto err_put; 1122 } 1123 1124 key = __bpf_copy_key(ukey, map->key_size); 1125 if (IS_ERR(key)) { 1126 err = PTR_ERR(key); 1127 goto err_put; 1128 } 1129 1130 value_size = map->value_size; 1131 1132 err = -ENOMEM; 1133 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1134 if (!value) 1135 goto free_key; 1136 1137 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1138 map->map_type == BPF_MAP_TYPE_STACK) { 1139 err = map->ops->map_pop_elem(map, value); 1140 } else { 1141 err = -ENOTSUPP; 1142 } 1143 1144 if (err) 1145 goto free_value; 1146 1147 if (copy_to_user(uvalue, value, value_size) != 0) 1148 goto free_value; 1149 1150 err = 0; 1151 1152 free_value: 1153 kfree(value); 1154 free_key: 1155 kfree(key); 1156 err_put: 1157 fdput(f); 1158 return err; 1159 } 1160 1161 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1162 1163 static int map_freeze(const union bpf_attr *attr) 1164 { 1165 int err = 0, ufd = attr->map_fd; 1166 struct bpf_map *map; 1167 struct fd f; 1168 1169 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1170 return -EINVAL; 1171 1172 f = fdget(ufd); 1173 map = __bpf_map_get(f); 1174 if (IS_ERR(map)) 1175 return PTR_ERR(map); 1176 if (READ_ONCE(map->frozen)) { 1177 err = -EBUSY; 1178 goto err_put; 1179 } 1180 if (!capable(CAP_SYS_ADMIN)) { 1181 err = -EPERM; 1182 goto err_put; 1183 } 1184 1185 WRITE_ONCE(map->frozen, true); 1186 err_put: 1187 fdput(f); 1188 return err; 1189 } 1190 1191 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1192 #define BPF_PROG_TYPE(_id, _name) \ 1193 [_id] = & _name ## _prog_ops, 1194 #define BPF_MAP_TYPE(_id, _ops) 1195 #include <linux/bpf_types.h> 1196 #undef BPF_PROG_TYPE 1197 #undef BPF_MAP_TYPE 1198 }; 1199 1200 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1201 { 1202 const struct bpf_prog_ops *ops; 1203 1204 if (type >= ARRAY_SIZE(bpf_prog_types)) 1205 return -EINVAL; 1206 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1207 ops = bpf_prog_types[type]; 1208 if (!ops) 1209 return -EINVAL; 1210 1211 if (!bpf_prog_is_dev_bound(prog->aux)) 1212 prog->aux->ops = ops; 1213 else 1214 prog->aux->ops = &bpf_offload_prog_ops; 1215 prog->type = type; 1216 return 0; 1217 } 1218 1219 /* drop refcnt on maps used by eBPF program and free auxilary data */ 1220 static void free_used_maps(struct bpf_prog_aux *aux) 1221 { 1222 enum bpf_cgroup_storage_type stype; 1223 int i; 1224 1225 for_each_cgroup_storage_type(stype) { 1226 if (!aux->cgroup_storage[stype]) 1227 continue; 1228 bpf_cgroup_storage_release(aux->prog, 1229 aux->cgroup_storage[stype]); 1230 } 1231 1232 for (i = 0; i < aux->used_map_cnt; i++) 1233 bpf_map_put(aux->used_maps[i]); 1234 1235 kfree(aux->used_maps); 1236 } 1237 1238 int __bpf_prog_charge(struct user_struct *user, u32 pages) 1239 { 1240 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 1241 unsigned long user_bufs; 1242 1243 if (user) { 1244 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 1245 if (user_bufs > memlock_limit) { 1246 atomic_long_sub(pages, &user->locked_vm); 1247 return -EPERM; 1248 } 1249 } 1250 1251 return 0; 1252 } 1253 1254 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 1255 { 1256 if (user) 1257 atomic_long_sub(pages, &user->locked_vm); 1258 } 1259 1260 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 1261 { 1262 struct user_struct *user = get_current_user(); 1263 int ret; 1264 1265 ret = __bpf_prog_charge(user, prog->pages); 1266 if (ret) { 1267 free_uid(user); 1268 return ret; 1269 } 1270 1271 prog->aux->user = user; 1272 return 0; 1273 } 1274 1275 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 1276 { 1277 struct user_struct *user = prog->aux->user; 1278 1279 __bpf_prog_uncharge(user, prog->pages); 1280 free_uid(user); 1281 } 1282 1283 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1284 { 1285 int id; 1286 1287 idr_preload(GFP_KERNEL); 1288 spin_lock_bh(&prog_idr_lock); 1289 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1290 if (id > 0) 1291 prog->aux->id = id; 1292 spin_unlock_bh(&prog_idr_lock); 1293 idr_preload_end(); 1294 1295 /* id is in [1, INT_MAX) */ 1296 if (WARN_ON_ONCE(!id)) 1297 return -ENOSPC; 1298 1299 return id > 0 ? 0 : id; 1300 } 1301 1302 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1303 { 1304 /* cBPF to eBPF migrations are currently not in the idr store. 1305 * Offloaded programs are removed from the store when their device 1306 * disappears - even if someone grabs an fd to them they are unusable, 1307 * simply waiting for refcnt to drop to be freed. 1308 */ 1309 if (!prog->aux->id) 1310 return; 1311 1312 if (do_idr_lock) 1313 spin_lock_bh(&prog_idr_lock); 1314 else 1315 __acquire(&prog_idr_lock); 1316 1317 idr_remove(&prog_idr, prog->aux->id); 1318 prog->aux->id = 0; 1319 1320 if (do_idr_lock) 1321 spin_unlock_bh(&prog_idr_lock); 1322 else 1323 __release(&prog_idr_lock); 1324 } 1325 1326 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1327 { 1328 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1329 1330 free_used_maps(aux); 1331 bpf_prog_uncharge_memlock(aux->prog); 1332 security_bpf_prog_free(aux); 1333 bpf_prog_free(aux->prog); 1334 } 1335 1336 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1337 { 1338 if (atomic_dec_and_test(&prog->aux->refcnt)) { 1339 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1340 /* bpf_prog_free_id() must be called first */ 1341 bpf_prog_free_id(prog, do_idr_lock); 1342 bpf_prog_kallsyms_del_all(prog); 1343 btf_put(prog->aux->btf); 1344 kvfree(prog->aux->func_info); 1345 bpf_prog_free_linfo(prog); 1346 1347 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1348 } 1349 } 1350 1351 void bpf_prog_put(struct bpf_prog *prog) 1352 { 1353 __bpf_prog_put(prog, true); 1354 } 1355 EXPORT_SYMBOL_GPL(bpf_prog_put); 1356 1357 static int bpf_prog_release(struct inode *inode, struct file *filp) 1358 { 1359 struct bpf_prog *prog = filp->private_data; 1360 1361 bpf_prog_put(prog); 1362 return 0; 1363 } 1364 1365 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1366 struct bpf_prog_stats *stats) 1367 { 1368 u64 nsecs = 0, cnt = 0; 1369 int cpu; 1370 1371 for_each_possible_cpu(cpu) { 1372 const struct bpf_prog_stats *st; 1373 unsigned int start; 1374 u64 tnsecs, tcnt; 1375 1376 st = per_cpu_ptr(prog->aux->stats, cpu); 1377 do { 1378 start = u64_stats_fetch_begin_irq(&st->syncp); 1379 tnsecs = st->nsecs; 1380 tcnt = st->cnt; 1381 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1382 nsecs += tnsecs; 1383 cnt += tcnt; 1384 } 1385 stats->nsecs = nsecs; 1386 stats->cnt = cnt; 1387 } 1388 1389 #ifdef CONFIG_PROC_FS 1390 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1391 { 1392 const struct bpf_prog *prog = filp->private_data; 1393 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1394 struct bpf_prog_stats stats; 1395 1396 bpf_prog_get_stats(prog, &stats); 1397 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1398 seq_printf(m, 1399 "prog_type:\t%u\n" 1400 "prog_jited:\t%u\n" 1401 "prog_tag:\t%s\n" 1402 "memlock:\t%llu\n" 1403 "prog_id:\t%u\n" 1404 "run_time_ns:\t%llu\n" 1405 "run_cnt:\t%llu\n", 1406 prog->type, 1407 prog->jited, 1408 prog_tag, 1409 prog->pages * 1ULL << PAGE_SHIFT, 1410 prog->aux->id, 1411 stats.nsecs, 1412 stats.cnt); 1413 } 1414 #endif 1415 1416 const struct file_operations bpf_prog_fops = { 1417 #ifdef CONFIG_PROC_FS 1418 .show_fdinfo = bpf_prog_show_fdinfo, 1419 #endif 1420 .release = bpf_prog_release, 1421 .read = bpf_dummy_read, 1422 .write = bpf_dummy_write, 1423 }; 1424 1425 int bpf_prog_new_fd(struct bpf_prog *prog) 1426 { 1427 int ret; 1428 1429 ret = security_bpf_prog(prog); 1430 if (ret < 0) 1431 return ret; 1432 1433 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1434 O_RDWR | O_CLOEXEC); 1435 } 1436 1437 static struct bpf_prog *____bpf_prog_get(struct fd f) 1438 { 1439 if (!f.file) 1440 return ERR_PTR(-EBADF); 1441 if (f.file->f_op != &bpf_prog_fops) { 1442 fdput(f); 1443 return ERR_PTR(-EINVAL); 1444 } 1445 1446 return f.file->private_data; 1447 } 1448 1449 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) 1450 { 1451 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) { 1452 atomic_sub(i, &prog->aux->refcnt); 1453 return ERR_PTR(-EBUSY); 1454 } 1455 return prog; 1456 } 1457 EXPORT_SYMBOL_GPL(bpf_prog_add); 1458 1459 void bpf_prog_sub(struct bpf_prog *prog, int i) 1460 { 1461 /* Only to be used for undoing previous bpf_prog_add() in some 1462 * error path. We still know that another entity in our call 1463 * path holds a reference to the program, thus atomic_sub() can 1464 * be safely used in such cases! 1465 */ 1466 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0); 1467 } 1468 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1469 1470 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) 1471 { 1472 return bpf_prog_add(prog, 1); 1473 } 1474 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1475 1476 /* prog_idr_lock should have been held */ 1477 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1478 { 1479 int refold; 1480 1481 refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1482 1483 if (refold >= BPF_MAX_REFCNT) { 1484 __bpf_prog_put(prog, false); 1485 return ERR_PTR(-EBUSY); 1486 } 1487 1488 if (!refold) 1489 return ERR_PTR(-ENOENT); 1490 1491 return prog; 1492 } 1493 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1494 1495 bool bpf_prog_get_ok(struct bpf_prog *prog, 1496 enum bpf_prog_type *attach_type, bool attach_drv) 1497 { 1498 /* not an attachment, just a refcount inc, always allow */ 1499 if (!attach_type) 1500 return true; 1501 1502 if (prog->type != *attach_type) 1503 return false; 1504 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1505 return false; 1506 1507 return true; 1508 } 1509 1510 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1511 bool attach_drv) 1512 { 1513 struct fd f = fdget(ufd); 1514 struct bpf_prog *prog; 1515 1516 prog = ____bpf_prog_get(f); 1517 if (IS_ERR(prog)) 1518 return prog; 1519 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1520 prog = ERR_PTR(-EINVAL); 1521 goto out; 1522 } 1523 1524 prog = bpf_prog_inc(prog); 1525 out: 1526 fdput(f); 1527 return prog; 1528 } 1529 1530 struct bpf_prog *bpf_prog_get(u32 ufd) 1531 { 1532 return __bpf_prog_get(ufd, NULL, false); 1533 } 1534 1535 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1536 bool attach_drv) 1537 { 1538 return __bpf_prog_get(ufd, &type, attach_drv); 1539 } 1540 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1541 1542 /* Initially all BPF programs could be loaded w/o specifying 1543 * expected_attach_type. Later for some of them specifying expected_attach_type 1544 * at load time became required so that program could be validated properly. 1545 * Programs of types that are allowed to be loaded both w/ and w/o (for 1546 * backward compatibility) expected_attach_type, should have the default attach 1547 * type assigned to expected_attach_type for the latter case, so that it can be 1548 * validated later at attach time. 1549 * 1550 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1551 * prog type requires it but has some attach types that have to be backward 1552 * compatible. 1553 */ 1554 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1555 { 1556 switch (attr->prog_type) { 1557 case BPF_PROG_TYPE_CGROUP_SOCK: 1558 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1559 * exist so checking for non-zero is the way to go here. 1560 */ 1561 if (!attr->expected_attach_type) 1562 attr->expected_attach_type = 1563 BPF_CGROUP_INET_SOCK_CREATE; 1564 break; 1565 } 1566 } 1567 1568 static int 1569 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 1570 enum bpf_attach_type expected_attach_type, 1571 u32 btf_id) 1572 { 1573 switch (prog_type) { 1574 case BPF_PROG_TYPE_RAW_TRACEPOINT: 1575 if (btf_id > BTF_MAX_TYPE) 1576 return -EINVAL; 1577 break; 1578 default: 1579 if (btf_id) 1580 return -EINVAL; 1581 break; 1582 } 1583 1584 switch (prog_type) { 1585 case BPF_PROG_TYPE_CGROUP_SOCK: 1586 switch (expected_attach_type) { 1587 case BPF_CGROUP_INET_SOCK_CREATE: 1588 case BPF_CGROUP_INET4_POST_BIND: 1589 case BPF_CGROUP_INET6_POST_BIND: 1590 return 0; 1591 default: 1592 return -EINVAL; 1593 } 1594 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1595 switch (expected_attach_type) { 1596 case BPF_CGROUP_INET4_BIND: 1597 case BPF_CGROUP_INET6_BIND: 1598 case BPF_CGROUP_INET4_CONNECT: 1599 case BPF_CGROUP_INET6_CONNECT: 1600 case BPF_CGROUP_UDP4_SENDMSG: 1601 case BPF_CGROUP_UDP6_SENDMSG: 1602 case BPF_CGROUP_UDP4_RECVMSG: 1603 case BPF_CGROUP_UDP6_RECVMSG: 1604 return 0; 1605 default: 1606 return -EINVAL; 1607 } 1608 case BPF_PROG_TYPE_CGROUP_SKB: 1609 switch (expected_attach_type) { 1610 case BPF_CGROUP_INET_INGRESS: 1611 case BPF_CGROUP_INET_EGRESS: 1612 return 0; 1613 default: 1614 return -EINVAL; 1615 } 1616 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1617 switch (expected_attach_type) { 1618 case BPF_CGROUP_SETSOCKOPT: 1619 case BPF_CGROUP_GETSOCKOPT: 1620 return 0; 1621 default: 1622 return -EINVAL; 1623 } 1624 default: 1625 return 0; 1626 } 1627 } 1628 1629 /* last field in 'union bpf_attr' used by this command */ 1630 #define BPF_PROG_LOAD_LAST_FIELD attach_btf_id 1631 1632 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 1633 { 1634 enum bpf_prog_type type = attr->prog_type; 1635 struct bpf_prog *prog; 1636 int err; 1637 char license[128]; 1638 bool is_gpl; 1639 1640 if (CHECK_ATTR(BPF_PROG_LOAD)) 1641 return -EINVAL; 1642 1643 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 1644 BPF_F_ANY_ALIGNMENT | 1645 BPF_F_TEST_STATE_FREQ | 1646 BPF_F_TEST_RND_HI32)) 1647 return -EINVAL; 1648 1649 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 1650 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 1651 !capable(CAP_SYS_ADMIN)) 1652 return -EPERM; 1653 1654 /* copy eBPF program license from user space */ 1655 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 1656 sizeof(license) - 1) < 0) 1657 return -EFAULT; 1658 license[sizeof(license) - 1] = 0; 1659 1660 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 1661 is_gpl = license_is_gpl_compatible(license); 1662 1663 if (attr->insn_cnt == 0 || 1664 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 1665 return -E2BIG; 1666 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 1667 type != BPF_PROG_TYPE_CGROUP_SKB && 1668 !capable(CAP_SYS_ADMIN)) 1669 return -EPERM; 1670 1671 bpf_prog_load_fixup_attach_type(attr); 1672 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 1673 attr->attach_btf_id)) 1674 return -EINVAL; 1675 1676 /* plain bpf_prog allocation */ 1677 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 1678 if (!prog) 1679 return -ENOMEM; 1680 1681 prog->expected_attach_type = attr->expected_attach_type; 1682 prog->aux->attach_btf_id = attr->attach_btf_id; 1683 1684 prog->aux->offload_requested = !!attr->prog_ifindex; 1685 1686 err = security_bpf_prog_alloc(prog->aux); 1687 if (err) 1688 goto free_prog_nouncharge; 1689 1690 err = bpf_prog_charge_memlock(prog); 1691 if (err) 1692 goto free_prog_sec; 1693 1694 prog->len = attr->insn_cnt; 1695 1696 err = -EFAULT; 1697 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 1698 bpf_prog_insn_size(prog)) != 0) 1699 goto free_prog; 1700 1701 prog->orig_prog = NULL; 1702 prog->jited = 0; 1703 1704 atomic_set(&prog->aux->refcnt, 1); 1705 prog->gpl_compatible = is_gpl ? 1 : 0; 1706 1707 if (bpf_prog_is_dev_bound(prog->aux)) { 1708 err = bpf_prog_offload_init(prog, attr); 1709 if (err) 1710 goto free_prog; 1711 } 1712 1713 /* find program type: socket_filter vs tracing_filter */ 1714 err = find_prog_type(type, prog); 1715 if (err < 0) 1716 goto free_prog; 1717 1718 prog->aux->load_time = ktime_get_boottime_ns(); 1719 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 1720 if (err) 1721 goto free_prog; 1722 1723 /* run eBPF verifier */ 1724 err = bpf_check(&prog, attr, uattr); 1725 if (err < 0) 1726 goto free_used_maps; 1727 1728 prog = bpf_prog_select_runtime(prog, &err); 1729 if (err < 0) 1730 goto free_used_maps; 1731 1732 err = bpf_prog_alloc_id(prog); 1733 if (err) 1734 goto free_used_maps; 1735 1736 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 1737 * effectively publicly exposed. However, retrieving via 1738 * bpf_prog_get_fd_by_id() will take another reference, 1739 * therefore it cannot be gone underneath us. 1740 * 1741 * Only for the time /after/ successful bpf_prog_new_fd() 1742 * and before returning to userspace, we might just hold 1743 * one reference and any parallel close on that fd could 1744 * rip everything out. Hence, below notifications must 1745 * happen before bpf_prog_new_fd(). 1746 * 1747 * Also, any failure handling from this point onwards must 1748 * be using bpf_prog_put() given the program is exposed. 1749 */ 1750 bpf_prog_kallsyms_add(prog); 1751 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 1752 1753 err = bpf_prog_new_fd(prog); 1754 if (err < 0) 1755 bpf_prog_put(prog); 1756 return err; 1757 1758 free_used_maps: 1759 bpf_prog_free_linfo(prog); 1760 kvfree(prog->aux->func_info); 1761 btf_put(prog->aux->btf); 1762 bpf_prog_kallsyms_del_subprogs(prog); 1763 free_used_maps(prog->aux); 1764 free_prog: 1765 bpf_prog_uncharge_memlock(prog); 1766 free_prog_sec: 1767 security_bpf_prog_free(prog->aux); 1768 free_prog_nouncharge: 1769 bpf_prog_free(prog); 1770 return err; 1771 } 1772 1773 #define BPF_OBJ_LAST_FIELD file_flags 1774 1775 static int bpf_obj_pin(const union bpf_attr *attr) 1776 { 1777 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 1778 return -EINVAL; 1779 1780 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 1781 } 1782 1783 static int bpf_obj_get(const union bpf_attr *attr) 1784 { 1785 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 1786 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 1787 return -EINVAL; 1788 1789 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 1790 attr->file_flags); 1791 } 1792 1793 struct bpf_raw_tracepoint { 1794 struct bpf_raw_event_map *btp; 1795 struct bpf_prog *prog; 1796 }; 1797 1798 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) 1799 { 1800 struct bpf_raw_tracepoint *raw_tp = filp->private_data; 1801 1802 if (raw_tp->prog) { 1803 bpf_probe_unregister(raw_tp->btp, raw_tp->prog); 1804 bpf_prog_put(raw_tp->prog); 1805 } 1806 bpf_put_raw_tracepoint(raw_tp->btp); 1807 kfree(raw_tp); 1808 return 0; 1809 } 1810 1811 static const struct file_operations bpf_raw_tp_fops = { 1812 .release = bpf_raw_tracepoint_release, 1813 .read = bpf_dummy_read, 1814 .write = bpf_dummy_write, 1815 }; 1816 1817 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 1818 1819 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 1820 { 1821 struct bpf_raw_tracepoint *raw_tp; 1822 struct bpf_raw_event_map *btp; 1823 struct bpf_prog *prog; 1824 const char *tp_name; 1825 char buf[128]; 1826 int tp_fd, err; 1827 1828 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 1829 return -EINVAL; 1830 1831 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 1832 if (IS_ERR(prog)) 1833 return PTR_ERR(prog); 1834 1835 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT && 1836 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) { 1837 err = -EINVAL; 1838 goto out_put_prog; 1839 } 1840 1841 if (prog->type == BPF_PROG_TYPE_RAW_TRACEPOINT && 1842 prog->aux->attach_btf_id) { 1843 if (attr->raw_tracepoint.name) { 1844 /* raw_tp name should not be specified in raw_tp 1845 * programs that were verified via in-kernel BTF info 1846 */ 1847 err = -EINVAL; 1848 goto out_put_prog; 1849 } 1850 /* raw_tp name is taken from type name instead */ 1851 tp_name = prog->aux->attach_func_name; 1852 } else { 1853 if (strncpy_from_user(buf, 1854 u64_to_user_ptr(attr->raw_tracepoint.name), 1855 sizeof(buf) - 1) < 0) { 1856 err = -EFAULT; 1857 goto out_put_prog; 1858 } 1859 buf[sizeof(buf) - 1] = 0; 1860 tp_name = buf; 1861 } 1862 1863 btp = bpf_get_raw_tracepoint(tp_name); 1864 if (!btp) { 1865 err = -ENOENT; 1866 goto out_put_prog; 1867 } 1868 1869 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 1870 if (!raw_tp) { 1871 err = -ENOMEM; 1872 goto out_put_btp; 1873 } 1874 raw_tp->btp = btp; 1875 raw_tp->prog = prog; 1876 1877 err = bpf_probe_register(raw_tp->btp, prog); 1878 if (err) 1879 goto out_free_tp; 1880 1881 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp, 1882 O_CLOEXEC); 1883 if (tp_fd < 0) { 1884 bpf_probe_unregister(raw_tp->btp, prog); 1885 err = tp_fd; 1886 goto out_free_tp; 1887 } 1888 return tp_fd; 1889 1890 out_free_tp: 1891 kfree(raw_tp); 1892 out_put_btp: 1893 bpf_put_raw_tracepoint(btp); 1894 out_put_prog: 1895 bpf_prog_put(prog); 1896 return err; 1897 } 1898 1899 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 1900 enum bpf_attach_type attach_type) 1901 { 1902 switch (prog->type) { 1903 case BPF_PROG_TYPE_CGROUP_SOCK: 1904 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1905 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1906 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 1907 case BPF_PROG_TYPE_CGROUP_SKB: 1908 return prog->enforce_expected_attach_type && 1909 prog->expected_attach_type != attach_type ? 1910 -EINVAL : 0; 1911 default: 1912 return 0; 1913 } 1914 } 1915 1916 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags 1917 1918 #define BPF_F_ATTACH_MASK \ 1919 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) 1920 1921 static int bpf_prog_attach(const union bpf_attr *attr) 1922 { 1923 enum bpf_prog_type ptype; 1924 struct bpf_prog *prog; 1925 int ret; 1926 1927 if (!capable(CAP_NET_ADMIN)) 1928 return -EPERM; 1929 1930 if (CHECK_ATTR(BPF_PROG_ATTACH)) 1931 return -EINVAL; 1932 1933 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 1934 return -EINVAL; 1935 1936 switch (attr->attach_type) { 1937 case BPF_CGROUP_INET_INGRESS: 1938 case BPF_CGROUP_INET_EGRESS: 1939 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1940 break; 1941 case BPF_CGROUP_INET_SOCK_CREATE: 1942 case BPF_CGROUP_INET4_POST_BIND: 1943 case BPF_CGROUP_INET6_POST_BIND: 1944 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1945 break; 1946 case BPF_CGROUP_INET4_BIND: 1947 case BPF_CGROUP_INET6_BIND: 1948 case BPF_CGROUP_INET4_CONNECT: 1949 case BPF_CGROUP_INET6_CONNECT: 1950 case BPF_CGROUP_UDP4_SENDMSG: 1951 case BPF_CGROUP_UDP6_SENDMSG: 1952 case BPF_CGROUP_UDP4_RECVMSG: 1953 case BPF_CGROUP_UDP6_RECVMSG: 1954 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1955 break; 1956 case BPF_CGROUP_SOCK_OPS: 1957 ptype = BPF_PROG_TYPE_SOCK_OPS; 1958 break; 1959 case BPF_CGROUP_DEVICE: 1960 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1961 break; 1962 case BPF_SK_MSG_VERDICT: 1963 ptype = BPF_PROG_TYPE_SK_MSG; 1964 break; 1965 case BPF_SK_SKB_STREAM_PARSER: 1966 case BPF_SK_SKB_STREAM_VERDICT: 1967 ptype = BPF_PROG_TYPE_SK_SKB; 1968 break; 1969 case BPF_LIRC_MODE2: 1970 ptype = BPF_PROG_TYPE_LIRC_MODE2; 1971 break; 1972 case BPF_FLOW_DISSECTOR: 1973 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR; 1974 break; 1975 case BPF_CGROUP_SYSCTL: 1976 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 1977 break; 1978 case BPF_CGROUP_GETSOCKOPT: 1979 case BPF_CGROUP_SETSOCKOPT: 1980 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 1981 break; 1982 default: 1983 return -EINVAL; 1984 } 1985 1986 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1987 if (IS_ERR(prog)) 1988 return PTR_ERR(prog); 1989 1990 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 1991 bpf_prog_put(prog); 1992 return -EINVAL; 1993 } 1994 1995 switch (ptype) { 1996 case BPF_PROG_TYPE_SK_SKB: 1997 case BPF_PROG_TYPE_SK_MSG: 1998 ret = sock_map_get_from_fd(attr, prog); 1999 break; 2000 case BPF_PROG_TYPE_LIRC_MODE2: 2001 ret = lirc_prog_attach(attr, prog); 2002 break; 2003 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2004 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 2005 break; 2006 default: 2007 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 2008 } 2009 2010 if (ret) 2011 bpf_prog_put(prog); 2012 return ret; 2013 } 2014 2015 #define BPF_PROG_DETACH_LAST_FIELD attach_type 2016 2017 static int bpf_prog_detach(const union bpf_attr *attr) 2018 { 2019 enum bpf_prog_type ptype; 2020 2021 if (!capable(CAP_NET_ADMIN)) 2022 return -EPERM; 2023 2024 if (CHECK_ATTR(BPF_PROG_DETACH)) 2025 return -EINVAL; 2026 2027 switch (attr->attach_type) { 2028 case BPF_CGROUP_INET_INGRESS: 2029 case BPF_CGROUP_INET_EGRESS: 2030 ptype = BPF_PROG_TYPE_CGROUP_SKB; 2031 break; 2032 case BPF_CGROUP_INET_SOCK_CREATE: 2033 case BPF_CGROUP_INET4_POST_BIND: 2034 case BPF_CGROUP_INET6_POST_BIND: 2035 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 2036 break; 2037 case BPF_CGROUP_INET4_BIND: 2038 case BPF_CGROUP_INET6_BIND: 2039 case BPF_CGROUP_INET4_CONNECT: 2040 case BPF_CGROUP_INET6_CONNECT: 2041 case BPF_CGROUP_UDP4_SENDMSG: 2042 case BPF_CGROUP_UDP6_SENDMSG: 2043 case BPF_CGROUP_UDP4_RECVMSG: 2044 case BPF_CGROUP_UDP6_RECVMSG: 2045 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 2046 break; 2047 case BPF_CGROUP_SOCK_OPS: 2048 ptype = BPF_PROG_TYPE_SOCK_OPS; 2049 break; 2050 case BPF_CGROUP_DEVICE: 2051 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 2052 break; 2053 case BPF_SK_MSG_VERDICT: 2054 return sock_map_get_from_fd(attr, NULL); 2055 case BPF_SK_SKB_STREAM_PARSER: 2056 case BPF_SK_SKB_STREAM_VERDICT: 2057 return sock_map_get_from_fd(attr, NULL); 2058 case BPF_LIRC_MODE2: 2059 return lirc_prog_detach(attr); 2060 case BPF_FLOW_DISSECTOR: 2061 return skb_flow_dissector_bpf_prog_detach(attr); 2062 case BPF_CGROUP_SYSCTL: 2063 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 2064 break; 2065 case BPF_CGROUP_GETSOCKOPT: 2066 case BPF_CGROUP_SETSOCKOPT: 2067 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 2068 break; 2069 default: 2070 return -EINVAL; 2071 } 2072 2073 return cgroup_bpf_prog_detach(attr, ptype); 2074 } 2075 2076 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 2077 2078 static int bpf_prog_query(const union bpf_attr *attr, 2079 union bpf_attr __user *uattr) 2080 { 2081 if (!capable(CAP_NET_ADMIN)) 2082 return -EPERM; 2083 if (CHECK_ATTR(BPF_PROG_QUERY)) 2084 return -EINVAL; 2085 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2086 return -EINVAL; 2087 2088 switch (attr->query.attach_type) { 2089 case BPF_CGROUP_INET_INGRESS: 2090 case BPF_CGROUP_INET_EGRESS: 2091 case BPF_CGROUP_INET_SOCK_CREATE: 2092 case BPF_CGROUP_INET4_BIND: 2093 case BPF_CGROUP_INET6_BIND: 2094 case BPF_CGROUP_INET4_POST_BIND: 2095 case BPF_CGROUP_INET6_POST_BIND: 2096 case BPF_CGROUP_INET4_CONNECT: 2097 case BPF_CGROUP_INET6_CONNECT: 2098 case BPF_CGROUP_UDP4_SENDMSG: 2099 case BPF_CGROUP_UDP6_SENDMSG: 2100 case BPF_CGROUP_UDP4_RECVMSG: 2101 case BPF_CGROUP_UDP6_RECVMSG: 2102 case BPF_CGROUP_SOCK_OPS: 2103 case BPF_CGROUP_DEVICE: 2104 case BPF_CGROUP_SYSCTL: 2105 case BPF_CGROUP_GETSOCKOPT: 2106 case BPF_CGROUP_SETSOCKOPT: 2107 break; 2108 case BPF_LIRC_MODE2: 2109 return lirc_prog_query(attr, uattr); 2110 case BPF_FLOW_DISSECTOR: 2111 return skb_flow_dissector_prog_query(attr, uattr); 2112 default: 2113 return -EINVAL; 2114 } 2115 2116 return cgroup_bpf_prog_query(attr, uattr); 2117 } 2118 2119 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2120 2121 static int bpf_prog_test_run(const union bpf_attr *attr, 2122 union bpf_attr __user *uattr) 2123 { 2124 struct bpf_prog *prog; 2125 int ret = -ENOTSUPP; 2126 2127 if (!capable(CAP_SYS_ADMIN)) 2128 return -EPERM; 2129 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2130 return -EINVAL; 2131 2132 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2133 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2134 return -EINVAL; 2135 2136 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2137 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2138 return -EINVAL; 2139 2140 prog = bpf_prog_get(attr->test.prog_fd); 2141 if (IS_ERR(prog)) 2142 return PTR_ERR(prog); 2143 2144 if (prog->aux->ops->test_run) 2145 ret = prog->aux->ops->test_run(prog, attr, uattr); 2146 2147 bpf_prog_put(prog); 2148 return ret; 2149 } 2150 2151 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2152 2153 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2154 union bpf_attr __user *uattr, 2155 struct idr *idr, 2156 spinlock_t *lock) 2157 { 2158 u32 next_id = attr->start_id; 2159 int err = 0; 2160 2161 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2162 return -EINVAL; 2163 2164 if (!capable(CAP_SYS_ADMIN)) 2165 return -EPERM; 2166 2167 next_id++; 2168 spin_lock_bh(lock); 2169 if (!idr_get_next(idr, &next_id)) 2170 err = -ENOENT; 2171 spin_unlock_bh(lock); 2172 2173 if (!err) 2174 err = put_user(next_id, &uattr->next_id); 2175 2176 return err; 2177 } 2178 2179 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2180 2181 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2182 { 2183 struct bpf_prog *prog; 2184 u32 id = attr->prog_id; 2185 int fd; 2186 2187 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2188 return -EINVAL; 2189 2190 if (!capable(CAP_SYS_ADMIN)) 2191 return -EPERM; 2192 2193 spin_lock_bh(&prog_idr_lock); 2194 prog = idr_find(&prog_idr, id); 2195 if (prog) 2196 prog = bpf_prog_inc_not_zero(prog); 2197 else 2198 prog = ERR_PTR(-ENOENT); 2199 spin_unlock_bh(&prog_idr_lock); 2200 2201 if (IS_ERR(prog)) 2202 return PTR_ERR(prog); 2203 2204 fd = bpf_prog_new_fd(prog); 2205 if (fd < 0) 2206 bpf_prog_put(prog); 2207 2208 return fd; 2209 } 2210 2211 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2212 2213 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2214 { 2215 struct bpf_map *map; 2216 u32 id = attr->map_id; 2217 int f_flags; 2218 int fd; 2219 2220 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2221 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2222 return -EINVAL; 2223 2224 if (!capable(CAP_SYS_ADMIN)) 2225 return -EPERM; 2226 2227 f_flags = bpf_get_file_flag(attr->open_flags); 2228 if (f_flags < 0) 2229 return f_flags; 2230 2231 spin_lock_bh(&map_idr_lock); 2232 map = idr_find(&map_idr, id); 2233 if (map) 2234 map = __bpf_map_inc_not_zero(map, true); 2235 else 2236 map = ERR_PTR(-ENOENT); 2237 spin_unlock_bh(&map_idr_lock); 2238 2239 if (IS_ERR(map)) 2240 return PTR_ERR(map); 2241 2242 fd = bpf_map_new_fd(map, f_flags); 2243 if (fd < 0) 2244 bpf_map_put_with_uref(map); 2245 2246 return fd; 2247 } 2248 2249 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2250 unsigned long addr, u32 *off, 2251 u32 *type) 2252 { 2253 const struct bpf_map *map; 2254 int i; 2255 2256 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2257 map = prog->aux->used_maps[i]; 2258 if (map == (void *)addr) { 2259 *type = BPF_PSEUDO_MAP_FD; 2260 return map; 2261 } 2262 if (!map->ops->map_direct_value_meta) 2263 continue; 2264 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2265 *type = BPF_PSEUDO_MAP_VALUE; 2266 return map; 2267 } 2268 } 2269 2270 return NULL; 2271 } 2272 2273 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2274 { 2275 const struct bpf_map *map; 2276 struct bpf_insn *insns; 2277 u32 off, type; 2278 u64 imm; 2279 int i; 2280 2281 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2282 GFP_USER); 2283 if (!insns) 2284 return insns; 2285 2286 for (i = 0; i < prog->len; i++) { 2287 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2288 insns[i].code = BPF_JMP | BPF_CALL; 2289 insns[i].imm = BPF_FUNC_tail_call; 2290 /* fall-through */ 2291 } 2292 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2293 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2294 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2295 insns[i].code = BPF_JMP | BPF_CALL; 2296 if (!bpf_dump_raw_ok()) 2297 insns[i].imm = 0; 2298 continue; 2299 } 2300 2301 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2302 continue; 2303 2304 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2305 map = bpf_map_from_imm(prog, imm, &off, &type); 2306 if (map) { 2307 insns[i].src_reg = type; 2308 insns[i].imm = map->id; 2309 insns[i + 1].imm = off; 2310 continue; 2311 } 2312 } 2313 2314 return insns; 2315 } 2316 2317 static int set_info_rec_size(struct bpf_prog_info *info) 2318 { 2319 /* 2320 * Ensure info.*_rec_size is the same as kernel expected size 2321 * 2322 * or 2323 * 2324 * Only allow zero *_rec_size if both _rec_size and _cnt are 2325 * zero. In this case, the kernel will set the expected 2326 * _rec_size back to the info. 2327 */ 2328 2329 if ((info->nr_func_info || info->func_info_rec_size) && 2330 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2331 return -EINVAL; 2332 2333 if ((info->nr_line_info || info->line_info_rec_size) && 2334 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2335 return -EINVAL; 2336 2337 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2338 info->jited_line_info_rec_size != sizeof(__u64)) 2339 return -EINVAL; 2340 2341 info->func_info_rec_size = sizeof(struct bpf_func_info); 2342 info->line_info_rec_size = sizeof(struct bpf_line_info); 2343 info->jited_line_info_rec_size = sizeof(__u64); 2344 2345 return 0; 2346 } 2347 2348 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2349 const union bpf_attr *attr, 2350 union bpf_attr __user *uattr) 2351 { 2352 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2353 struct bpf_prog_info info = {}; 2354 u32 info_len = attr->info.info_len; 2355 struct bpf_prog_stats stats; 2356 char __user *uinsns; 2357 u32 ulen; 2358 int err; 2359 2360 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2361 if (err) 2362 return err; 2363 info_len = min_t(u32, sizeof(info), info_len); 2364 2365 if (copy_from_user(&info, uinfo, info_len)) 2366 return -EFAULT; 2367 2368 info.type = prog->type; 2369 info.id = prog->aux->id; 2370 info.load_time = prog->aux->load_time; 2371 info.created_by_uid = from_kuid_munged(current_user_ns(), 2372 prog->aux->user->uid); 2373 info.gpl_compatible = prog->gpl_compatible; 2374 2375 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 2376 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 2377 2378 ulen = info.nr_map_ids; 2379 info.nr_map_ids = prog->aux->used_map_cnt; 2380 ulen = min_t(u32, info.nr_map_ids, ulen); 2381 if (ulen) { 2382 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 2383 u32 i; 2384 2385 for (i = 0; i < ulen; i++) 2386 if (put_user(prog->aux->used_maps[i]->id, 2387 &user_map_ids[i])) 2388 return -EFAULT; 2389 } 2390 2391 err = set_info_rec_size(&info); 2392 if (err) 2393 return err; 2394 2395 bpf_prog_get_stats(prog, &stats); 2396 info.run_time_ns = stats.nsecs; 2397 info.run_cnt = stats.cnt; 2398 2399 if (!capable(CAP_SYS_ADMIN)) { 2400 info.jited_prog_len = 0; 2401 info.xlated_prog_len = 0; 2402 info.nr_jited_ksyms = 0; 2403 info.nr_jited_func_lens = 0; 2404 info.nr_func_info = 0; 2405 info.nr_line_info = 0; 2406 info.nr_jited_line_info = 0; 2407 goto done; 2408 } 2409 2410 ulen = info.xlated_prog_len; 2411 info.xlated_prog_len = bpf_prog_insn_size(prog); 2412 if (info.xlated_prog_len && ulen) { 2413 struct bpf_insn *insns_sanitized; 2414 bool fault; 2415 2416 if (prog->blinded && !bpf_dump_raw_ok()) { 2417 info.xlated_prog_insns = 0; 2418 goto done; 2419 } 2420 insns_sanitized = bpf_insn_prepare_dump(prog); 2421 if (!insns_sanitized) 2422 return -ENOMEM; 2423 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 2424 ulen = min_t(u32, info.xlated_prog_len, ulen); 2425 fault = copy_to_user(uinsns, insns_sanitized, ulen); 2426 kfree(insns_sanitized); 2427 if (fault) 2428 return -EFAULT; 2429 } 2430 2431 if (bpf_prog_is_dev_bound(prog->aux)) { 2432 err = bpf_prog_offload_info_fill(&info, prog); 2433 if (err) 2434 return err; 2435 goto done; 2436 } 2437 2438 /* NOTE: the following code is supposed to be skipped for offload. 2439 * bpf_prog_offload_info_fill() is the place to fill similar fields 2440 * for offload. 2441 */ 2442 ulen = info.jited_prog_len; 2443 if (prog->aux->func_cnt) { 2444 u32 i; 2445 2446 info.jited_prog_len = 0; 2447 for (i = 0; i < prog->aux->func_cnt; i++) 2448 info.jited_prog_len += prog->aux->func[i]->jited_len; 2449 } else { 2450 info.jited_prog_len = prog->jited_len; 2451 } 2452 2453 if (info.jited_prog_len && ulen) { 2454 if (bpf_dump_raw_ok()) { 2455 uinsns = u64_to_user_ptr(info.jited_prog_insns); 2456 ulen = min_t(u32, info.jited_prog_len, ulen); 2457 2458 /* for multi-function programs, copy the JITed 2459 * instructions for all the functions 2460 */ 2461 if (prog->aux->func_cnt) { 2462 u32 len, free, i; 2463 u8 *img; 2464 2465 free = ulen; 2466 for (i = 0; i < prog->aux->func_cnt; i++) { 2467 len = prog->aux->func[i]->jited_len; 2468 len = min_t(u32, len, free); 2469 img = (u8 *) prog->aux->func[i]->bpf_func; 2470 if (copy_to_user(uinsns, img, len)) 2471 return -EFAULT; 2472 uinsns += len; 2473 free -= len; 2474 if (!free) 2475 break; 2476 } 2477 } else { 2478 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 2479 return -EFAULT; 2480 } 2481 } else { 2482 info.jited_prog_insns = 0; 2483 } 2484 } 2485 2486 ulen = info.nr_jited_ksyms; 2487 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 2488 if (ulen) { 2489 if (bpf_dump_raw_ok()) { 2490 unsigned long ksym_addr; 2491 u64 __user *user_ksyms; 2492 u32 i; 2493 2494 /* copy the address of the kernel symbol 2495 * corresponding to each function 2496 */ 2497 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 2498 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 2499 if (prog->aux->func_cnt) { 2500 for (i = 0; i < ulen; i++) { 2501 ksym_addr = (unsigned long) 2502 prog->aux->func[i]->bpf_func; 2503 if (put_user((u64) ksym_addr, 2504 &user_ksyms[i])) 2505 return -EFAULT; 2506 } 2507 } else { 2508 ksym_addr = (unsigned long) prog->bpf_func; 2509 if (put_user((u64) ksym_addr, &user_ksyms[0])) 2510 return -EFAULT; 2511 } 2512 } else { 2513 info.jited_ksyms = 0; 2514 } 2515 } 2516 2517 ulen = info.nr_jited_func_lens; 2518 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 2519 if (ulen) { 2520 if (bpf_dump_raw_ok()) { 2521 u32 __user *user_lens; 2522 u32 func_len, i; 2523 2524 /* copy the JITed image lengths for each function */ 2525 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 2526 user_lens = u64_to_user_ptr(info.jited_func_lens); 2527 if (prog->aux->func_cnt) { 2528 for (i = 0; i < ulen; i++) { 2529 func_len = 2530 prog->aux->func[i]->jited_len; 2531 if (put_user(func_len, &user_lens[i])) 2532 return -EFAULT; 2533 } 2534 } else { 2535 func_len = prog->jited_len; 2536 if (put_user(func_len, &user_lens[0])) 2537 return -EFAULT; 2538 } 2539 } else { 2540 info.jited_func_lens = 0; 2541 } 2542 } 2543 2544 if (prog->aux->btf) 2545 info.btf_id = btf_id(prog->aux->btf); 2546 2547 ulen = info.nr_func_info; 2548 info.nr_func_info = prog->aux->func_info_cnt; 2549 if (info.nr_func_info && ulen) { 2550 char __user *user_finfo; 2551 2552 user_finfo = u64_to_user_ptr(info.func_info); 2553 ulen = min_t(u32, info.nr_func_info, ulen); 2554 if (copy_to_user(user_finfo, prog->aux->func_info, 2555 info.func_info_rec_size * ulen)) 2556 return -EFAULT; 2557 } 2558 2559 ulen = info.nr_line_info; 2560 info.nr_line_info = prog->aux->nr_linfo; 2561 if (info.nr_line_info && ulen) { 2562 __u8 __user *user_linfo; 2563 2564 user_linfo = u64_to_user_ptr(info.line_info); 2565 ulen = min_t(u32, info.nr_line_info, ulen); 2566 if (copy_to_user(user_linfo, prog->aux->linfo, 2567 info.line_info_rec_size * ulen)) 2568 return -EFAULT; 2569 } 2570 2571 ulen = info.nr_jited_line_info; 2572 if (prog->aux->jited_linfo) 2573 info.nr_jited_line_info = prog->aux->nr_linfo; 2574 else 2575 info.nr_jited_line_info = 0; 2576 if (info.nr_jited_line_info && ulen) { 2577 if (bpf_dump_raw_ok()) { 2578 __u64 __user *user_linfo; 2579 u32 i; 2580 2581 user_linfo = u64_to_user_ptr(info.jited_line_info); 2582 ulen = min_t(u32, info.nr_jited_line_info, ulen); 2583 for (i = 0; i < ulen; i++) { 2584 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 2585 &user_linfo[i])) 2586 return -EFAULT; 2587 } 2588 } else { 2589 info.jited_line_info = 0; 2590 } 2591 } 2592 2593 ulen = info.nr_prog_tags; 2594 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 2595 if (ulen) { 2596 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 2597 u32 i; 2598 2599 user_prog_tags = u64_to_user_ptr(info.prog_tags); 2600 ulen = min_t(u32, info.nr_prog_tags, ulen); 2601 if (prog->aux->func_cnt) { 2602 for (i = 0; i < ulen; i++) { 2603 if (copy_to_user(user_prog_tags[i], 2604 prog->aux->func[i]->tag, 2605 BPF_TAG_SIZE)) 2606 return -EFAULT; 2607 } 2608 } else { 2609 if (copy_to_user(user_prog_tags[0], 2610 prog->tag, BPF_TAG_SIZE)) 2611 return -EFAULT; 2612 } 2613 } 2614 2615 done: 2616 if (copy_to_user(uinfo, &info, info_len) || 2617 put_user(info_len, &uattr->info.info_len)) 2618 return -EFAULT; 2619 2620 return 0; 2621 } 2622 2623 static int bpf_map_get_info_by_fd(struct bpf_map *map, 2624 const union bpf_attr *attr, 2625 union bpf_attr __user *uattr) 2626 { 2627 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2628 struct bpf_map_info info = {}; 2629 u32 info_len = attr->info.info_len; 2630 int err; 2631 2632 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2633 if (err) 2634 return err; 2635 info_len = min_t(u32, sizeof(info), info_len); 2636 2637 info.type = map->map_type; 2638 info.id = map->id; 2639 info.key_size = map->key_size; 2640 info.value_size = map->value_size; 2641 info.max_entries = map->max_entries; 2642 info.map_flags = map->map_flags; 2643 memcpy(info.name, map->name, sizeof(map->name)); 2644 2645 if (map->btf) { 2646 info.btf_id = btf_id(map->btf); 2647 info.btf_key_type_id = map->btf_key_type_id; 2648 info.btf_value_type_id = map->btf_value_type_id; 2649 } 2650 2651 if (bpf_map_is_dev_bound(map)) { 2652 err = bpf_map_offload_info_fill(&info, map); 2653 if (err) 2654 return err; 2655 } 2656 2657 if (copy_to_user(uinfo, &info, info_len) || 2658 put_user(info_len, &uattr->info.info_len)) 2659 return -EFAULT; 2660 2661 return 0; 2662 } 2663 2664 static int bpf_btf_get_info_by_fd(struct btf *btf, 2665 const union bpf_attr *attr, 2666 union bpf_attr __user *uattr) 2667 { 2668 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2669 u32 info_len = attr->info.info_len; 2670 int err; 2671 2672 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 2673 if (err) 2674 return err; 2675 2676 return btf_get_info_by_fd(btf, attr, uattr); 2677 } 2678 2679 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 2680 2681 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 2682 union bpf_attr __user *uattr) 2683 { 2684 int ufd = attr->info.bpf_fd; 2685 struct fd f; 2686 int err; 2687 2688 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 2689 return -EINVAL; 2690 2691 f = fdget(ufd); 2692 if (!f.file) 2693 return -EBADFD; 2694 2695 if (f.file->f_op == &bpf_prog_fops) 2696 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 2697 uattr); 2698 else if (f.file->f_op == &bpf_map_fops) 2699 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 2700 uattr); 2701 else if (f.file->f_op == &btf_fops) 2702 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 2703 else 2704 err = -EINVAL; 2705 2706 fdput(f); 2707 return err; 2708 } 2709 2710 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 2711 2712 static int bpf_btf_load(const union bpf_attr *attr) 2713 { 2714 if (CHECK_ATTR(BPF_BTF_LOAD)) 2715 return -EINVAL; 2716 2717 if (!capable(CAP_SYS_ADMIN)) 2718 return -EPERM; 2719 2720 return btf_new_fd(attr); 2721 } 2722 2723 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 2724 2725 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 2726 { 2727 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 2728 return -EINVAL; 2729 2730 if (!capable(CAP_SYS_ADMIN)) 2731 return -EPERM; 2732 2733 return btf_get_fd_by_id(attr->btf_id); 2734 } 2735 2736 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 2737 union bpf_attr __user *uattr, 2738 u32 prog_id, u32 fd_type, 2739 const char *buf, u64 probe_offset, 2740 u64 probe_addr) 2741 { 2742 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 2743 u32 len = buf ? strlen(buf) : 0, input_len; 2744 int err = 0; 2745 2746 if (put_user(len, &uattr->task_fd_query.buf_len)) 2747 return -EFAULT; 2748 input_len = attr->task_fd_query.buf_len; 2749 if (input_len && ubuf) { 2750 if (!len) { 2751 /* nothing to copy, just make ubuf NULL terminated */ 2752 char zero = '\0'; 2753 2754 if (put_user(zero, ubuf)) 2755 return -EFAULT; 2756 } else if (input_len >= len + 1) { 2757 /* ubuf can hold the string with NULL terminator */ 2758 if (copy_to_user(ubuf, buf, len + 1)) 2759 return -EFAULT; 2760 } else { 2761 /* ubuf cannot hold the string with NULL terminator, 2762 * do a partial copy with NULL terminator. 2763 */ 2764 char zero = '\0'; 2765 2766 err = -ENOSPC; 2767 if (copy_to_user(ubuf, buf, input_len - 1)) 2768 return -EFAULT; 2769 if (put_user(zero, ubuf + input_len - 1)) 2770 return -EFAULT; 2771 } 2772 } 2773 2774 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 2775 put_user(fd_type, &uattr->task_fd_query.fd_type) || 2776 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 2777 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 2778 return -EFAULT; 2779 2780 return err; 2781 } 2782 2783 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 2784 2785 static int bpf_task_fd_query(const union bpf_attr *attr, 2786 union bpf_attr __user *uattr) 2787 { 2788 pid_t pid = attr->task_fd_query.pid; 2789 u32 fd = attr->task_fd_query.fd; 2790 const struct perf_event *event; 2791 struct files_struct *files; 2792 struct task_struct *task; 2793 struct file *file; 2794 int err; 2795 2796 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 2797 return -EINVAL; 2798 2799 if (!capable(CAP_SYS_ADMIN)) 2800 return -EPERM; 2801 2802 if (attr->task_fd_query.flags != 0) 2803 return -EINVAL; 2804 2805 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 2806 if (!task) 2807 return -ENOENT; 2808 2809 files = get_files_struct(task); 2810 put_task_struct(task); 2811 if (!files) 2812 return -ENOENT; 2813 2814 err = 0; 2815 spin_lock(&files->file_lock); 2816 file = fcheck_files(files, fd); 2817 if (!file) 2818 err = -EBADF; 2819 else 2820 get_file(file); 2821 spin_unlock(&files->file_lock); 2822 put_files_struct(files); 2823 2824 if (err) 2825 goto out; 2826 2827 if (file->f_op == &bpf_raw_tp_fops) { 2828 struct bpf_raw_tracepoint *raw_tp = file->private_data; 2829 struct bpf_raw_event_map *btp = raw_tp->btp; 2830 2831 err = bpf_task_fd_query_copy(attr, uattr, 2832 raw_tp->prog->aux->id, 2833 BPF_FD_TYPE_RAW_TRACEPOINT, 2834 btp->tp->name, 0, 0); 2835 goto put_file; 2836 } 2837 2838 event = perf_get_event(file); 2839 if (!IS_ERR(event)) { 2840 u64 probe_offset, probe_addr; 2841 u32 prog_id, fd_type; 2842 const char *buf; 2843 2844 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 2845 &buf, &probe_offset, 2846 &probe_addr); 2847 if (!err) 2848 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 2849 fd_type, buf, 2850 probe_offset, 2851 probe_addr); 2852 goto put_file; 2853 } 2854 2855 err = -ENOTSUPP; 2856 put_file: 2857 fput(file); 2858 out: 2859 return err; 2860 } 2861 2862 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 2863 { 2864 union bpf_attr attr = {}; 2865 int err; 2866 2867 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 2868 return -EPERM; 2869 2870 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 2871 if (err) 2872 return err; 2873 size = min_t(u32, size, sizeof(attr)); 2874 2875 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 2876 if (copy_from_user(&attr, uattr, size) != 0) 2877 return -EFAULT; 2878 2879 err = security_bpf(cmd, &attr, size); 2880 if (err < 0) 2881 return err; 2882 2883 switch (cmd) { 2884 case BPF_MAP_CREATE: 2885 err = map_create(&attr); 2886 break; 2887 case BPF_MAP_LOOKUP_ELEM: 2888 err = map_lookup_elem(&attr); 2889 break; 2890 case BPF_MAP_UPDATE_ELEM: 2891 err = map_update_elem(&attr); 2892 break; 2893 case BPF_MAP_DELETE_ELEM: 2894 err = map_delete_elem(&attr); 2895 break; 2896 case BPF_MAP_GET_NEXT_KEY: 2897 err = map_get_next_key(&attr); 2898 break; 2899 case BPF_MAP_FREEZE: 2900 err = map_freeze(&attr); 2901 break; 2902 case BPF_PROG_LOAD: 2903 err = bpf_prog_load(&attr, uattr); 2904 break; 2905 case BPF_OBJ_PIN: 2906 err = bpf_obj_pin(&attr); 2907 break; 2908 case BPF_OBJ_GET: 2909 err = bpf_obj_get(&attr); 2910 break; 2911 case BPF_PROG_ATTACH: 2912 err = bpf_prog_attach(&attr); 2913 break; 2914 case BPF_PROG_DETACH: 2915 err = bpf_prog_detach(&attr); 2916 break; 2917 case BPF_PROG_QUERY: 2918 err = bpf_prog_query(&attr, uattr); 2919 break; 2920 case BPF_PROG_TEST_RUN: 2921 err = bpf_prog_test_run(&attr, uattr); 2922 break; 2923 case BPF_PROG_GET_NEXT_ID: 2924 err = bpf_obj_get_next_id(&attr, uattr, 2925 &prog_idr, &prog_idr_lock); 2926 break; 2927 case BPF_MAP_GET_NEXT_ID: 2928 err = bpf_obj_get_next_id(&attr, uattr, 2929 &map_idr, &map_idr_lock); 2930 break; 2931 case BPF_BTF_GET_NEXT_ID: 2932 err = bpf_obj_get_next_id(&attr, uattr, 2933 &btf_idr, &btf_idr_lock); 2934 break; 2935 case BPF_PROG_GET_FD_BY_ID: 2936 err = bpf_prog_get_fd_by_id(&attr); 2937 break; 2938 case BPF_MAP_GET_FD_BY_ID: 2939 err = bpf_map_get_fd_by_id(&attr); 2940 break; 2941 case BPF_OBJ_GET_INFO_BY_FD: 2942 err = bpf_obj_get_info_by_fd(&attr, uattr); 2943 break; 2944 case BPF_RAW_TRACEPOINT_OPEN: 2945 err = bpf_raw_tracepoint_open(&attr); 2946 break; 2947 case BPF_BTF_LOAD: 2948 err = bpf_btf_load(&attr); 2949 break; 2950 case BPF_BTF_GET_FD_BY_ID: 2951 err = bpf_btf_get_fd_by_id(&attr); 2952 break; 2953 case BPF_TASK_FD_QUERY: 2954 err = bpf_task_fd_query(&attr, uattr); 2955 break; 2956 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 2957 err = map_lookup_and_delete_elem(&attr); 2958 break; 2959 default: 2960 err = -EINVAL; 2961 break; 2962 } 2963 2964 return err; 2965 } 2966