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 27 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \ 28 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 29 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 30 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 31 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 32 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map)) 33 34 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 35 36 DEFINE_PER_CPU(int, bpf_prog_active); 37 static DEFINE_IDR(prog_idr); 38 static DEFINE_SPINLOCK(prog_idr_lock); 39 static DEFINE_IDR(map_idr); 40 static DEFINE_SPINLOCK(map_idr_lock); 41 42 int sysctl_unprivileged_bpf_disabled __read_mostly; 43 44 static const struct bpf_map_ops * const bpf_map_types[] = { 45 #define BPF_PROG_TYPE(_id, _ops) 46 #define BPF_MAP_TYPE(_id, _ops) \ 47 [_id] = &_ops, 48 #include <linux/bpf_types.h> 49 #undef BPF_PROG_TYPE 50 #undef BPF_MAP_TYPE 51 }; 52 53 /* 54 * If we're handed a bigger struct than we know of, ensure all the unknown bits 55 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 56 * we don't know about yet. 57 * 58 * There is a ToCToU between this function call and the following 59 * copy_from_user() call. However, this is not a concern since this function is 60 * meant to be a future-proofing of bits. 61 */ 62 int bpf_check_uarg_tail_zero(void __user *uaddr, 63 size_t expected_size, 64 size_t actual_size) 65 { 66 unsigned char __user *addr; 67 unsigned char __user *end; 68 unsigned char val; 69 int err; 70 71 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 72 return -E2BIG; 73 74 if (unlikely(!access_ok(uaddr, actual_size))) 75 return -EFAULT; 76 77 if (actual_size <= expected_size) 78 return 0; 79 80 addr = uaddr + expected_size; 81 end = uaddr + actual_size; 82 83 for (; addr < end; addr++) { 84 err = get_user(val, addr); 85 if (err) 86 return err; 87 if (val) 88 return -E2BIG; 89 } 90 91 return 0; 92 } 93 94 const struct bpf_map_ops bpf_map_offload_ops = { 95 .map_alloc = bpf_map_offload_map_alloc, 96 .map_free = bpf_map_offload_map_free, 97 .map_check_btf = map_check_no_btf, 98 }; 99 100 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 101 { 102 const struct bpf_map_ops *ops; 103 u32 type = attr->map_type; 104 struct bpf_map *map; 105 int err; 106 107 if (type >= ARRAY_SIZE(bpf_map_types)) 108 return ERR_PTR(-EINVAL); 109 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 110 ops = bpf_map_types[type]; 111 if (!ops) 112 return ERR_PTR(-EINVAL); 113 114 if (ops->map_alloc_check) { 115 err = ops->map_alloc_check(attr); 116 if (err) 117 return ERR_PTR(err); 118 } 119 if (attr->map_ifindex) 120 ops = &bpf_map_offload_ops; 121 map = ops->map_alloc(attr); 122 if (IS_ERR(map)) 123 return map; 124 map->ops = ops; 125 map->map_type = type; 126 return map; 127 } 128 129 void *bpf_map_area_alloc(size_t size, int numa_node) 130 { 131 /* We really just want to fail instead of triggering OOM killer 132 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 133 * which is used for lower order allocation requests. 134 * 135 * It has been observed that higher order allocation requests done by 136 * vmalloc with __GFP_NORETRY being set might fail due to not trying 137 * to reclaim memory from the page cache, thus we set 138 * __GFP_RETRY_MAYFAIL to avoid such situations. 139 */ 140 141 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; 142 void *area; 143 144 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 145 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, 146 numa_node); 147 if (area != NULL) 148 return area; 149 } 150 151 return __vmalloc_node_flags_caller(size, numa_node, 152 GFP_KERNEL | __GFP_RETRY_MAYFAIL | 153 flags, __builtin_return_address(0)); 154 } 155 156 void bpf_map_area_free(void *area) 157 { 158 kvfree(area); 159 } 160 161 static u32 bpf_map_flags_retain_permanent(u32 flags) 162 { 163 /* Some map creation flags are not tied to the map object but 164 * rather to the map fd instead, so they have no meaning upon 165 * map object inspection since multiple file descriptors with 166 * different (access) properties can exist here. Thus, given 167 * this has zero meaning for the map itself, lets clear these 168 * from here. 169 */ 170 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 171 } 172 173 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 174 { 175 map->map_type = attr->map_type; 176 map->key_size = attr->key_size; 177 map->value_size = attr->value_size; 178 map->max_entries = attr->max_entries; 179 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 180 map->numa_node = bpf_map_attr_numa_node(attr); 181 } 182 183 static int bpf_charge_memlock(struct user_struct *user, u32 pages) 184 { 185 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 186 187 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) { 188 atomic_long_sub(pages, &user->locked_vm); 189 return -EPERM; 190 } 191 return 0; 192 } 193 194 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages) 195 { 196 if (user) 197 atomic_long_sub(pages, &user->locked_vm); 198 } 199 200 int bpf_map_charge_init(struct bpf_map_memory *mem, size_t size) 201 { 202 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT; 203 struct user_struct *user; 204 int ret; 205 206 if (size >= U32_MAX - PAGE_SIZE) 207 return -E2BIG; 208 209 user = get_current_user(); 210 ret = bpf_charge_memlock(user, pages); 211 if (ret) { 212 free_uid(user); 213 return ret; 214 } 215 216 mem->pages = pages; 217 mem->user = user; 218 219 return 0; 220 } 221 222 void bpf_map_charge_finish(struct bpf_map_memory *mem) 223 { 224 bpf_uncharge_memlock(mem->user, mem->pages); 225 free_uid(mem->user); 226 } 227 228 void bpf_map_charge_move(struct bpf_map_memory *dst, 229 struct bpf_map_memory *src) 230 { 231 *dst = *src; 232 233 /* Make sure src will not be used for the redundant uncharging. */ 234 memset(src, 0, sizeof(struct bpf_map_memory)); 235 } 236 237 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages) 238 { 239 int ret; 240 241 ret = bpf_charge_memlock(map->memory.user, pages); 242 if (ret) 243 return ret; 244 map->memory.pages += pages; 245 return ret; 246 } 247 248 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages) 249 { 250 bpf_uncharge_memlock(map->memory.user, pages); 251 map->memory.pages -= pages; 252 } 253 254 static int bpf_map_alloc_id(struct bpf_map *map) 255 { 256 int id; 257 258 idr_preload(GFP_KERNEL); 259 spin_lock_bh(&map_idr_lock); 260 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 261 if (id > 0) 262 map->id = id; 263 spin_unlock_bh(&map_idr_lock); 264 idr_preload_end(); 265 266 if (WARN_ON_ONCE(!id)) 267 return -ENOSPC; 268 269 return id > 0 ? 0 : id; 270 } 271 272 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 273 { 274 unsigned long flags; 275 276 /* Offloaded maps are removed from the IDR store when their device 277 * disappears - even if someone holds an fd to them they are unusable, 278 * the memory is gone, all ops will fail; they are simply waiting for 279 * refcnt to drop to be freed. 280 */ 281 if (!map->id) 282 return; 283 284 if (do_idr_lock) 285 spin_lock_irqsave(&map_idr_lock, flags); 286 else 287 __acquire(&map_idr_lock); 288 289 idr_remove(&map_idr, map->id); 290 map->id = 0; 291 292 if (do_idr_lock) 293 spin_unlock_irqrestore(&map_idr_lock, flags); 294 else 295 __release(&map_idr_lock); 296 } 297 298 /* called from workqueue */ 299 static void bpf_map_free_deferred(struct work_struct *work) 300 { 301 struct bpf_map *map = container_of(work, struct bpf_map, work); 302 struct bpf_map_memory mem; 303 304 bpf_map_charge_move(&mem, &map->memory); 305 security_bpf_map_free(map); 306 /* implementation dependent freeing */ 307 map->ops->map_free(map); 308 bpf_map_charge_finish(&mem); 309 } 310 311 static void bpf_map_put_uref(struct bpf_map *map) 312 { 313 if (atomic_dec_and_test(&map->usercnt)) { 314 if (map->ops->map_release_uref) 315 map->ops->map_release_uref(map); 316 } 317 } 318 319 /* decrement map refcnt and schedule it for freeing via workqueue 320 * (unrelying map implementation ops->map_free() might sleep) 321 */ 322 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 323 { 324 if (atomic_dec_and_test(&map->refcnt)) { 325 /* bpf_map_free_id() must be called first */ 326 bpf_map_free_id(map, do_idr_lock); 327 btf_put(map->btf); 328 INIT_WORK(&map->work, bpf_map_free_deferred); 329 schedule_work(&map->work); 330 } 331 } 332 333 void bpf_map_put(struct bpf_map *map) 334 { 335 __bpf_map_put(map, true); 336 } 337 EXPORT_SYMBOL_GPL(bpf_map_put); 338 339 void bpf_map_put_with_uref(struct bpf_map *map) 340 { 341 bpf_map_put_uref(map); 342 bpf_map_put(map); 343 } 344 345 static int bpf_map_release(struct inode *inode, struct file *filp) 346 { 347 struct bpf_map *map = filp->private_data; 348 349 if (map->ops->map_release) 350 map->ops->map_release(map, filp); 351 352 bpf_map_put_with_uref(map); 353 return 0; 354 } 355 356 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 357 { 358 fmode_t mode = f.file->f_mode; 359 360 /* Our file permissions may have been overridden by global 361 * map permissions facing syscall side. 362 */ 363 if (READ_ONCE(map->frozen)) 364 mode &= ~FMODE_CAN_WRITE; 365 return mode; 366 } 367 368 #ifdef CONFIG_PROC_FS 369 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 370 { 371 const struct bpf_map *map = filp->private_data; 372 const struct bpf_array *array; 373 u32 owner_prog_type = 0; 374 u32 owner_jited = 0; 375 376 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 377 array = container_of(map, struct bpf_array, map); 378 owner_prog_type = array->owner_prog_type; 379 owner_jited = array->owner_jited; 380 } 381 382 seq_printf(m, 383 "map_type:\t%u\n" 384 "key_size:\t%u\n" 385 "value_size:\t%u\n" 386 "max_entries:\t%u\n" 387 "map_flags:\t%#x\n" 388 "memlock:\t%llu\n" 389 "map_id:\t%u\n" 390 "frozen:\t%u\n", 391 map->map_type, 392 map->key_size, 393 map->value_size, 394 map->max_entries, 395 map->map_flags, 396 map->memory.pages * 1ULL << PAGE_SHIFT, 397 map->id, 398 READ_ONCE(map->frozen)); 399 400 if (owner_prog_type) { 401 seq_printf(m, "owner_prog_type:\t%u\n", 402 owner_prog_type); 403 seq_printf(m, "owner_jited:\t%u\n", 404 owner_jited); 405 } 406 } 407 #endif 408 409 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 410 loff_t *ppos) 411 { 412 /* We need this handler such that alloc_file() enables 413 * f_mode with FMODE_CAN_READ. 414 */ 415 return -EINVAL; 416 } 417 418 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 419 size_t siz, loff_t *ppos) 420 { 421 /* We need this handler such that alloc_file() enables 422 * f_mode with FMODE_CAN_WRITE. 423 */ 424 return -EINVAL; 425 } 426 427 const struct file_operations bpf_map_fops = { 428 #ifdef CONFIG_PROC_FS 429 .show_fdinfo = bpf_map_show_fdinfo, 430 #endif 431 .release = bpf_map_release, 432 .read = bpf_dummy_read, 433 .write = bpf_dummy_write, 434 }; 435 436 int bpf_map_new_fd(struct bpf_map *map, int flags) 437 { 438 int ret; 439 440 ret = security_bpf_map(map, OPEN_FMODE(flags)); 441 if (ret < 0) 442 return ret; 443 444 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 445 flags | O_CLOEXEC); 446 } 447 448 int bpf_get_file_flag(int flags) 449 { 450 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 451 return -EINVAL; 452 if (flags & BPF_F_RDONLY) 453 return O_RDONLY; 454 if (flags & BPF_F_WRONLY) 455 return O_WRONLY; 456 return O_RDWR; 457 } 458 459 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 460 #define CHECK_ATTR(CMD) \ 461 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 462 sizeof(attr->CMD##_LAST_FIELD), 0, \ 463 sizeof(*attr) - \ 464 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 465 sizeof(attr->CMD##_LAST_FIELD)) != NULL 466 467 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes. 468 * Return 0 on success and < 0 on error. 469 */ 470 static int bpf_obj_name_cpy(char *dst, const char *src) 471 { 472 const char *end = src + BPF_OBJ_NAME_LEN; 473 474 memset(dst, 0, BPF_OBJ_NAME_LEN); 475 /* Copy all isalnum(), '_' and '.' chars. */ 476 while (src < end && *src) { 477 if (!isalnum(*src) && 478 *src != '_' && *src != '.') 479 return -EINVAL; 480 *dst++ = *src++; 481 } 482 483 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */ 484 if (src == end) 485 return -EINVAL; 486 487 return 0; 488 } 489 490 int map_check_no_btf(const struct bpf_map *map, 491 const struct btf *btf, 492 const struct btf_type *key_type, 493 const struct btf_type *value_type) 494 { 495 return -ENOTSUPP; 496 } 497 498 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 499 u32 btf_key_id, u32 btf_value_id) 500 { 501 const struct btf_type *key_type, *value_type; 502 u32 key_size, value_size; 503 int ret = 0; 504 505 /* Some maps allow key to be unspecified. */ 506 if (btf_key_id) { 507 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 508 if (!key_type || key_size != map->key_size) 509 return -EINVAL; 510 } else { 511 key_type = btf_type_by_id(btf, 0); 512 if (!map->ops->map_check_btf) 513 return -EINVAL; 514 } 515 516 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 517 if (!value_type || value_size != map->value_size) 518 return -EINVAL; 519 520 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 521 522 if (map_value_has_spin_lock(map)) { 523 if (map->map_flags & BPF_F_RDONLY_PROG) 524 return -EACCES; 525 if (map->map_type != BPF_MAP_TYPE_HASH && 526 map->map_type != BPF_MAP_TYPE_ARRAY && 527 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 528 map->map_type != BPF_MAP_TYPE_SK_STORAGE) 529 return -ENOTSUPP; 530 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 531 map->value_size) { 532 WARN_ONCE(1, 533 "verifier bug spin_lock_off %d value_size %d\n", 534 map->spin_lock_off, map->value_size); 535 return -EFAULT; 536 } 537 } 538 539 if (map->ops->map_check_btf) 540 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 541 542 return ret; 543 } 544 545 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id 546 /* called via syscall */ 547 static int map_create(union bpf_attr *attr) 548 { 549 int numa_node = bpf_map_attr_numa_node(attr); 550 struct bpf_map_memory mem; 551 struct bpf_map *map; 552 int f_flags; 553 int err; 554 555 err = CHECK_ATTR(BPF_MAP_CREATE); 556 if (err) 557 return -EINVAL; 558 559 f_flags = bpf_get_file_flag(attr->map_flags); 560 if (f_flags < 0) 561 return f_flags; 562 563 if (numa_node != NUMA_NO_NODE && 564 ((unsigned int)numa_node >= nr_node_ids || 565 !node_online(numa_node))) 566 return -EINVAL; 567 568 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 569 map = find_and_alloc_map(attr); 570 if (IS_ERR(map)) 571 return PTR_ERR(map); 572 573 err = bpf_obj_name_cpy(map->name, attr->map_name); 574 if (err) 575 goto free_map; 576 577 atomic_set(&map->refcnt, 1); 578 atomic_set(&map->usercnt, 1); 579 580 if (attr->btf_key_type_id || attr->btf_value_type_id) { 581 struct btf *btf; 582 583 if (!attr->btf_value_type_id) { 584 err = -EINVAL; 585 goto free_map; 586 } 587 588 btf = btf_get_by_fd(attr->btf_fd); 589 if (IS_ERR(btf)) { 590 err = PTR_ERR(btf); 591 goto free_map; 592 } 593 594 err = map_check_btf(map, btf, attr->btf_key_type_id, 595 attr->btf_value_type_id); 596 if (err) { 597 btf_put(btf); 598 goto free_map; 599 } 600 601 map->btf = btf; 602 map->btf_key_type_id = attr->btf_key_type_id; 603 map->btf_value_type_id = attr->btf_value_type_id; 604 } else { 605 map->spin_lock_off = -EINVAL; 606 } 607 608 err = security_bpf_map_alloc(map); 609 if (err) 610 goto free_map; 611 612 err = bpf_map_alloc_id(map); 613 if (err) 614 goto free_map_sec; 615 616 err = bpf_map_new_fd(map, f_flags); 617 if (err < 0) { 618 /* failed to allocate fd. 619 * bpf_map_put_with_uref() is needed because the above 620 * bpf_map_alloc_id() has published the map 621 * to the userspace and the userspace may 622 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 623 */ 624 bpf_map_put_with_uref(map); 625 return err; 626 } 627 628 return err; 629 630 free_map_sec: 631 security_bpf_map_free(map); 632 free_map: 633 btf_put(map->btf); 634 bpf_map_charge_move(&mem, &map->memory); 635 map->ops->map_free(map); 636 bpf_map_charge_finish(&mem); 637 return err; 638 } 639 640 /* if error is returned, fd is released. 641 * On success caller should complete fd access with matching fdput() 642 */ 643 struct bpf_map *__bpf_map_get(struct fd f) 644 { 645 if (!f.file) 646 return ERR_PTR(-EBADF); 647 if (f.file->f_op != &bpf_map_fops) { 648 fdput(f); 649 return ERR_PTR(-EINVAL); 650 } 651 652 return f.file->private_data; 653 } 654 655 /* prog's and map's refcnt limit */ 656 #define BPF_MAX_REFCNT 32768 657 658 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) 659 { 660 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { 661 atomic_dec(&map->refcnt); 662 return ERR_PTR(-EBUSY); 663 } 664 if (uref) 665 atomic_inc(&map->usercnt); 666 return map; 667 } 668 EXPORT_SYMBOL_GPL(bpf_map_inc); 669 670 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 671 { 672 struct fd f = fdget(ufd); 673 struct bpf_map *map; 674 675 map = __bpf_map_get(f); 676 if (IS_ERR(map)) 677 return map; 678 679 map = bpf_map_inc(map, true); 680 fdput(f); 681 682 return map; 683 } 684 685 /* map_idr_lock should have been held */ 686 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, 687 bool uref) 688 { 689 int refold; 690 691 refold = atomic_fetch_add_unless(&map->refcnt, 1, 0); 692 693 if (refold >= BPF_MAX_REFCNT) { 694 __bpf_map_put(map, false); 695 return ERR_PTR(-EBUSY); 696 } 697 698 if (!refold) 699 return ERR_PTR(-ENOENT); 700 701 if (uref) 702 atomic_inc(&map->usercnt); 703 704 return map; 705 } 706 707 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 708 { 709 return -ENOTSUPP; 710 } 711 712 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 713 { 714 if (key_size) 715 return memdup_user(ukey, key_size); 716 717 if (ukey) 718 return ERR_PTR(-EINVAL); 719 720 return NULL; 721 } 722 723 /* last field in 'union bpf_attr' used by this command */ 724 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 725 726 static int map_lookup_elem(union bpf_attr *attr) 727 { 728 void __user *ukey = u64_to_user_ptr(attr->key); 729 void __user *uvalue = u64_to_user_ptr(attr->value); 730 int ufd = attr->map_fd; 731 struct bpf_map *map; 732 void *key, *value, *ptr; 733 u32 value_size; 734 struct fd f; 735 int err; 736 737 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 738 return -EINVAL; 739 740 if (attr->flags & ~BPF_F_LOCK) 741 return -EINVAL; 742 743 f = fdget(ufd); 744 map = __bpf_map_get(f); 745 if (IS_ERR(map)) 746 return PTR_ERR(map); 747 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 748 err = -EPERM; 749 goto err_put; 750 } 751 752 if ((attr->flags & BPF_F_LOCK) && 753 !map_value_has_spin_lock(map)) { 754 err = -EINVAL; 755 goto err_put; 756 } 757 758 key = __bpf_copy_key(ukey, map->key_size); 759 if (IS_ERR(key)) { 760 err = PTR_ERR(key); 761 goto err_put; 762 } 763 764 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 765 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 766 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 767 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 768 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 769 else if (IS_FD_MAP(map)) 770 value_size = sizeof(u32); 771 else 772 value_size = map->value_size; 773 774 err = -ENOMEM; 775 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 776 if (!value) 777 goto free_key; 778 779 if (bpf_map_is_dev_bound(map)) { 780 err = bpf_map_offload_lookup_elem(map, key, value); 781 goto done; 782 } 783 784 preempt_disable(); 785 this_cpu_inc(bpf_prog_active); 786 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 787 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 788 err = bpf_percpu_hash_copy(map, key, value); 789 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 790 err = bpf_percpu_array_copy(map, key, value); 791 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 792 err = bpf_percpu_cgroup_storage_copy(map, key, value); 793 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 794 err = bpf_stackmap_copy(map, key, value); 795 } else if (IS_FD_ARRAY(map)) { 796 err = bpf_fd_array_map_lookup_elem(map, key, value); 797 } else if (IS_FD_HASH(map)) { 798 err = bpf_fd_htab_map_lookup_elem(map, key, value); 799 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 800 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 801 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 802 map->map_type == BPF_MAP_TYPE_STACK) { 803 err = map->ops->map_peek_elem(map, value); 804 } else { 805 rcu_read_lock(); 806 if (map->ops->map_lookup_elem_sys_only) 807 ptr = map->ops->map_lookup_elem_sys_only(map, key); 808 else 809 ptr = map->ops->map_lookup_elem(map, key); 810 if (IS_ERR(ptr)) { 811 err = PTR_ERR(ptr); 812 } else if (!ptr) { 813 err = -ENOENT; 814 } else { 815 err = 0; 816 if (attr->flags & BPF_F_LOCK) 817 /* lock 'ptr' and copy everything but lock */ 818 copy_map_value_locked(map, value, ptr, true); 819 else 820 copy_map_value(map, value, ptr); 821 /* mask lock, since value wasn't zero inited */ 822 check_and_init_map_lock(map, value); 823 } 824 rcu_read_unlock(); 825 } 826 this_cpu_dec(bpf_prog_active); 827 preempt_enable(); 828 829 done: 830 if (err) 831 goto free_value; 832 833 err = -EFAULT; 834 if (copy_to_user(uvalue, value, value_size) != 0) 835 goto free_value; 836 837 err = 0; 838 839 free_value: 840 kfree(value); 841 free_key: 842 kfree(key); 843 err_put: 844 fdput(f); 845 return err; 846 } 847 848 static void maybe_wait_bpf_programs(struct bpf_map *map) 849 { 850 /* Wait for any running BPF programs to complete so that 851 * userspace, when we return to it, knows that all programs 852 * that could be running use the new map value. 853 */ 854 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 855 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 856 synchronize_rcu(); 857 } 858 859 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 860 861 static int map_update_elem(union bpf_attr *attr) 862 { 863 void __user *ukey = u64_to_user_ptr(attr->key); 864 void __user *uvalue = u64_to_user_ptr(attr->value); 865 int ufd = attr->map_fd; 866 struct bpf_map *map; 867 void *key, *value; 868 u32 value_size; 869 struct fd f; 870 int err; 871 872 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 873 return -EINVAL; 874 875 f = fdget(ufd); 876 map = __bpf_map_get(f); 877 if (IS_ERR(map)) 878 return PTR_ERR(map); 879 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 880 err = -EPERM; 881 goto err_put; 882 } 883 884 if ((attr->flags & BPF_F_LOCK) && 885 !map_value_has_spin_lock(map)) { 886 err = -EINVAL; 887 goto err_put; 888 } 889 890 key = __bpf_copy_key(ukey, map->key_size); 891 if (IS_ERR(key)) { 892 err = PTR_ERR(key); 893 goto err_put; 894 } 895 896 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 897 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 898 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 899 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 900 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 901 else 902 value_size = map->value_size; 903 904 err = -ENOMEM; 905 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 906 if (!value) 907 goto free_key; 908 909 err = -EFAULT; 910 if (copy_from_user(value, uvalue, value_size) != 0) 911 goto free_value; 912 913 /* Need to create a kthread, thus must support schedule */ 914 if (bpf_map_is_dev_bound(map)) { 915 err = bpf_map_offload_update_elem(map, key, value, attr->flags); 916 goto out; 917 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 918 map->map_type == BPF_MAP_TYPE_SOCKHASH || 919 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 920 err = map->ops->map_update_elem(map, key, value, attr->flags); 921 goto out; 922 } 923 924 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from 925 * inside bpf map update or delete otherwise deadlocks are possible 926 */ 927 preempt_disable(); 928 __this_cpu_inc(bpf_prog_active); 929 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 930 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 931 err = bpf_percpu_hash_update(map, key, value, attr->flags); 932 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 933 err = bpf_percpu_array_update(map, key, value, attr->flags); 934 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 935 err = bpf_percpu_cgroup_storage_update(map, key, value, 936 attr->flags); 937 } else if (IS_FD_ARRAY(map)) { 938 rcu_read_lock(); 939 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 940 attr->flags); 941 rcu_read_unlock(); 942 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 943 rcu_read_lock(); 944 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 945 attr->flags); 946 rcu_read_unlock(); 947 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 948 /* rcu_read_lock() is not needed */ 949 err = bpf_fd_reuseport_array_update_elem(map, key, value, 950 attr->flags); 951 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 952 map->map_type == BPF_MAP_TYPE_STACK) { 953 err = map->ops->map_push_elem(map, value, attr->flags); 954 } else { 955 rcu_read_lock(); 956 err = map->ops->map_update_elem(map, key, value, attr->flags); 957 rcu_read_unlock(); 958 } 959 __this_cpu_dec(bpf_prog_active); 960 preempt_enable(); 961 maybe_wait_bpf_programs(map); 962 out: 963 free_value: 964 kfree(value); 965 free_key: 966 kfree(key); 967 err_put: 968 fdput(f); 969 return err; 970 } 971 972 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 973 974 static int map_delete_elem(union bpf_attr *attr) 975 { 976 void __user *ukey = u64_to_user_ptr(attr->key); 977 int ufd = attr->map_fd; 978 struct bpf_map *map; 979 struct fd f; 980 void *key; 981 int err; 982 983 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 984 return -EINVAL; 985 986 f = fdget(ufd); 987 map = __bpf_map_get(f); 988 if (IS_ERR(map)) 989 return PTR_ERR(map); 990 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 991 err = -EPERM; 992 goto err_put; 993 } 994 995 key = __bpf_copy_key(ukey, map->key_size); 996 if (IS_ERR(key)) { 997 err = PTR_ERR(key); 998 goto err_put; 999 } 1000 1001 if (bpf_map_is_dev_bound(map)) { 1002 err = bpf_map_offload_delete_elem(map, key); 1003 goto out; 1004 } 1005 1006 preempt_disable(); 1007 __this_cpu_inc(bpf_prog_active); 1008 rcu_read_lock(); 1009 err = map->ops->map_delete_elem(map, key); 1010 rcu_read_unlock(); 1011 __this_cpu_dec(bpf_prog_active); 1012 preempt_enable(); 1013 maybe_wait_bpf_programs(map); 1014 out: 1015 kfree(key); 1016 err_put: 1017 fdput(f); 1018 return err; 1019 } 1020 1021 /* last field in 'union bpf_attr' used by this command */ 1022 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1023 1024 static int map_get_next_key(union bpf_attr *attr) 1025 { 1026 void __user *ukey = u64_to_user_ptr(attr->key); 1027 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1028 int ufd = attr->map_fd; 1029 struct bpf_map *map; 1030 void *key, *next_key; 1031 struct fd f; 1032 int err; 1033 1034 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1035 return -EINVAL; 1036 1037 f = fdget(ufd); 1038 map = __bpf_map_get(f); 1039 if (IS_ERR(map)) 1040 return PTR_ERR(map); 1041 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1042 err = -EPERM; 1043 goto err_put; 1044 } 1045 1046 if (ukey) { 1047 key = __bpf_copy_key(ukey, map->key_size); 1048 if (IS_ERR(key)) { 1049 err = PTR_ERR(key); 1050 goto err_put; 1051 } 1052 } else { 1053 key = NULL; 1054 } 1055 1056 err = -ENOMEM; 1057 next_key = kmalloc(map->key_size, GFP_USER); 1058 if (!next_key) 1059 goto free_key; 1060 1061 if (bpf_map_is_dev_bound(map)) { 1062 err = bpf_map_offload_get_next_key(map, key, next_key); 1063 goto out; 1064 } 1065 1066 rcu_read_lock(); 1067 err = map->ops->map_get_next_key(map, key, next_key); 1068 rcu_read_unlock(); 1069 out: 1070 if (err) 1071 goto free_next_key; 1072 1073 err = -EFAULT; 1074 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1075 goto free_next_key; 1076 1077 err = 0; 1078 1079 free_next_key: 1080 kfree(next_key); 1081 free_key: 1082 kfree(key); 1083 err_put: 1084 fdput(f); 1085 return err; 1086 } 1087 1088 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value 1089 1090 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1091 { 1092 void __user *ukey = u64_to_user_ptr(attr->key); 1093 void __user *uvalue = u64_to_user_ptr(attr->value); 1094 int ufd = attr->map_fd; 1095 struct bpf_map *map; 1096 void *key, *value; 1097 u32 value_size; 1098 struct fd f; 1099 int err; 1100 1101 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1102 return -EINVAL; 1103 1104 f = fdget(ufd); 1105 map = __bpf_map_get(f); 1106 if (IS_ERR(map)) 1107 return PTR_ERR(map); 1108 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1109 err = -EPERM; 1110 goto err_put; 1111 } 1112 1113 key = __bpf_copy_key(ukey, map->key_size); 1114 if (IS_ERR(key)) { 1115 err = PTR_ERR(key); 1116 goto err_put; 1117 } 1118 1119 value_size = map->value_size; 1120 1121 err = -ENOMEM; 1122 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1123 if (!value) 1124 goto free_key; 1125 1126 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1127 map->map_type == BPF_MAP_TYPE_STACK) { 1128 err = map->ops->map_pop_elem(map, value); 1129 } else { 1130 err = -ENOTSUPP; 1131 } 1132 1133 if (err) 1134 goto free_value; 1135 1136 if (copy_to_user(uvalue, value, value_size) != 0) 1137 goto free_value; 1138 1139 err = 0; 1140 1141 free_value: 1142 kfree(value); 1143 free_key: 1144 kfree(key); 1145 err_put: 1146 fdput(f); 1147 return err; 1148 } 1149 1150 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1151 1152 static int map_freeze(const union bpf_attr *attr) 1153 { 1154 int err = 0, ufd = attr->map_fd; 1155 struct bpf_map *map; 1156 struct fd f; 1157 1158 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1159 return -EINVAL; 1160 1161 f = fdget(ufd); 1162 map = __bpf_map_get(f); 1163 if (IS_ERR(map)) 1164 return PTR_ERR(map); 1165 if (READ_ONCE(map->frozen)) { 1166 err = -EBUSY; 1167 goto err_put; 1168 } 1169 if (!capable(CAP_SYS_ADMIN)) { 1170 err = -EPERM; 1171 goto err_put; 1172 } 1173 1174 WRITE_ONCE(map->frozen, true); 1175 err_put: 1176 fdput(f); 1177 return err; 1178 } 1179 1180 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1181 #define BPF_PROG_TYPE(_id, _name) \ 1182 [_id] = & _name ## _prog_ops, 1183 #define BPF_MAP_TYPE(_id, _ops) 1184 #include <linux/bpf_types.h> 1185 #undef BPF_PROG_TYPE 1186 #undef BPF_MAP_TYPE 1187 }; 1188 1189 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1190 { 1191 const struct bpf_prog_ops *ops; 1192 1193 if (type >= ARRAY_SIZE(bpf_prog_types)) 1194 return -EINVAL; 1195 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1196 ops = bpf_prog_types[type]; 1197 if (!ops) 1198 return -EINVAL; 1199 1200 if (!bpf_prog_is_dev_bound(prog->aux)) 1201 prog->aux->ops = ops; 1202 else 1203 prog->aux->ops = &bpf_offload_prog_ops; 1204 prog->type = type; 1205 return 0; 1206 } 1207 1208 /* drop refcnt on maps used by eBPF program and free auxilary data */ 1209 static void free_used_maps(struct bpf_prog_aux *aux) 1210 { 1211 enum bpf_cgroup_storage_type stype; 1212 int i; 1213 1214 for_each_cgroup_storage_type(stype) { 1215 if (!aux->cgroup_storage[stype]) 1216 continue; 1217 bpf_cgroup_storage_release(aux->prog, 1218 aux->cgroup_storage[stype]); 1219 } 1220 1221 for (i = 0; i < aux->used_map_cnt; i++) 1222 bpf_map_put(aux->used_maps[i]); 1223 1224 kfree(aux->used_maps); 1225 } 1226 1227 int __bpf_prog_charge(struct user_struct *user, u32 pages) 1228 { 1229 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 1230 unsigned long user_bufs; 1231 1232 if (user) { 1233 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 1234 if (user_bufs > memlock_limit) { 1235 atomic_long_sub(pages, &user->locked_vm); 1236 return -EPERM; 1237 } 1238 } 1239 1240 return 0; 1241 } 1242 1243 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 1244 { 1245 if (user) 1246 atomic_long_sub(pages, &user->locked_vm); 1247 } 1248 1249 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 1250 { 1251 struct user_struct *user = get_current_user(); 1252 int ret; 1253 1254 ret = __bpf_prog_charge(user, prog->pages); 1255 if (ret) { 1256 free_uid(user); 1257 return ret; 1258 } 1259 1260 prog->aux->user = user; 1261 return 0; 1262 } 1263 1264 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 1265 { 1266 struct user_struct *user = prog->aux->user; 1267 1268 __bpf_prog_uncharge(user, prog->pages); 1269 free_uid(user); 1270 } 1271 1272 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1273 { 1274 int id; 1275 1276 idr_preload(GFP_KERNEL); 1277 spin_lock_bh(&prog_idr_lock); 1278 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1279 if (id > 0) 1280 prog->aux->id = id; 1281 spin_unlock_bh(&prog_idr_lock); 1282 idr_preload_end(); 1283 1284 /* id is in [1, INT_MAX) */ 1285 if (WARN_ON_ONCE(!id)) 1286 return -ENOSPC; 1287 1288 return id > 0 ? 0 : id; 1289 } 1290 1291 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1292 { 1293 /* cBPF to eBPF migrations are currently not in the idr store. 1294 * Offloaded programs are removed from the store when their device 1295 * disappears - even if someone grabs an fd to them they are unusable, 1296 * simply waiting for refcnt to drop to be freed. 1297 */ 1298 if (!prog->aux->id) 1299 return; 1300 1301 if (do_idr_lock) 1302 spin_lock_bh(&prog_idr_lock); 1303 else 1304 __acquire(&prog_idr_lock); 1305 1306 idr_remove(&prog_idr, prog->aux->id); 1307 prog->aux->id = 0; 1308 1309 if (do_idr_lock) 1310 spin_unlock_bh(&prog_idr_lock); 1311 else 1312 __release(&prog_idr_lock); 1313 } 1314 1315 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1316 { 1317 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1318 1319 free_used_maps(aux); 1320 bpf_prog_uncharge_memlock(aux->prog); 1321 security_bpf_prog_free(aux); 1322 bpf_prog_free(aux->prog); 1323 } 1324 1325 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1326 { 1327 if (atomic_dec_and_test(&prog->aux->refcnt)) { 1328 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1329 /* bpf_prog_free_id() must be called first */ 1330 bpf_prog_free_id(prog, do_idr_lock); 1331 bpf_prog_kallsyms_del_all(prog); 1332 btf_put(prog->aux->btf); 1333 kvfree(prog->aux->func_info); 1334 bpf_prog_free_linfo(prog); 1335 1336 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1337 } 1338 } 1339 1340 void bpf_prog_put(struct bpf_prog *prog) 1341 { 1342 __bpf_prog_put(prog, true); 1343 } 1344 EXPORT_SYMBOL_GPL(bpf_prog_put); 1345 1346 static int bpf_prog_release(struct inode *inode, struct file *filp) 1347 { 1348 struct bpf_prog *prog = filp->private_data; 1349 1350 bpf_prog_put(prog); 1351 return 0; 1352 } 1353 1354 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1355 struct bpf_prog_stats *stats) 1356 { 1357 u64 nsecs = 0, cnt = 0; 1358 int cpu; 1359 1360 for_each_possible_cpu(cpu) { 1361 const struct bpf_prog_stats *st; 1362 unsigned int start; 1363 u64 tnsecs, tcnt; 1364 1365 st = per_cpu_ptr(prog->aux->stats, cpu); 1366 do { 1367 start = u64_stats_fetch_begin_irq(&st->syncp); 1368 tnsecs = st->nsecs; 1369 tcnt = st->cnt; 1370 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1371 nsecs += tnsecs; 1372 cnt += tcnt; 1373 } 1374 stats->nsecs = nsecs; 1375 stats->cnt = cnt; 1376 } 1377 1378 #ifdef CONFIG_PROC_FS 1379 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1380 { 1381 const struct bpf_prog *prog = filp->private_data; 1382 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1383 struct bpf_prog_stats stats; 1384 1385 bpf_prog_get_stats(prog, &stats); 1386 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1387 seq_printf(m, 1388 "prog_type:\t%u\n" 1389 "prog_jited:\t%u\n" 1390 "prog_tag:\t%s\n" 1391 "memlock:\t%llu\n" 1392 "prog_id:\t%u\n" 1393 "run_time_ns:\t%llu\n" 1394 "run_cnt:\t%llu\n", 1395 prog->type, 1396 prog->jited, 1397 prog_tag, 1398 prog->pages * 1ULL << PAGE_SHIFT, 1399 prog->aux->id, 1400 stats.nsecs, 1401 stats.cnt); 1402 } 1403 #endif 1404 1405 const struct file_operations bpf_prog_fops = { 1406 #ifdef CONFIG_PROC_FS 1407 .show_fdinfo = bpf_prog_show_fdinfo, 1408 #endif 1409 .release = bpf_prog_release, 1410 .read = bpf_dummy_read, 1411 .write = bpf_dummy_write, 1412 }; 1413 1414 int bpf_prog_new_fd(struct bpf_prog *prog) 1415 { 1416 int ret; 1417 1418 ret = security_bpf_prog(prog); 1419 if (ret < 0) 1420 return ret; 1421 1422 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1423 O_RDWR | O_CLOEXEC); 1424 } 1425 1426 static struct bpf_prog *____bpf_prog_get(struct fd f) 1427 { 1428 if (!f.file) 1429 return ERR_PTR(-EBADF); 1430 if (f.file->f_op != &bpf_prog_fops) { 1431 fdput(f); 1432 return ERR_PTR(-EINVAL); 1433 } 1434 1435 return f.file->private_data; 1436 } 1437 1438 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) 1439 { 1440 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) { 1441 atomic_sub(i, &prog->aux->refcnt); 1442 return ERR_PTR(-EBUSY); 1443 } 1444 return prog; 1445 } 1446 EXPORT_SYMBOL_GPL(bpf_prog_add); 1447 1448 void bpf_prog_sub(struct bpf_prog *prog, int i) 1449 { 1450 /* Only to be used for undoing previous bpf_prog_add() in some 1451 * error path. We still know that another entity in our call 1452 * path holds a reference to the program, thus atomic_sub() can 1453 * be safely used in such cases! 1454 */ 1455 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0); 1456 } 1457 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1458 1459 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) 1460 { 1461 return bpf_prog_add(prog, 1); 1462 } 1463 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1464 1465 /* prog_idr_lock should have been held */ 1466 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1467 { 1468 int refold; 1469 1470 refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1471 1472 if (refold >= BPF_MAX_REFCNT) { 1473 __bpf_prog_put(prog, false); 1474 return ERR_PTR(-EBUSY); 1475 } 1476 1477 if (!refold) 1478 return ERR_PTR(-ENOENT); 1479 1480 return prog; 1481 } 1482 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1483 1484 bool bpf_prog_get_ok(struct bpf_prog *prog, 1485 enum bpf_prog_type *attach_type, bool attach_drv) 1486 { 1487 /* not an attachment, just a refcount inc, always allow */ 1488 if (!attach_type) 1489 return true; 1490 1491 if (prog->type != *attach_type) 1492 return false; 1493 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1494 return false; 1495 1496 return true; 1497 } 1498 1499 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1500 bool attach_drv) 1501 { 1502 struct fd f = fdget(ufd); 1503 struct bpf_prog *prog; 1504 1505 prog = ____bpf_prog_get(f); 1506 if (IS_ERR(prog)) 1507 return prog; 1508 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1509 prog = ERR_PTR(-EINVAL); 1510 goto out; 1511 } 1512 1513 prog = bpf_prog_inc(prog); 1514 out: 1515 fdput(f); 1516 return prog; 1517 } 1518 1519 struct bpf_prog *bpf_prog_get(u32 ufd) 1520 { 1521 return __bpf_prog_get(ufd, NULL, false); 1522 } 1523 1524 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1525 bool attach_drv) 1526 { 1527 return __bpf_prog_get(ufd, &type, attach_drv); 1528 } 1529 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1530 1531 /* Initially all BPF programs could be loaded w/o specifying 1532 * expected_attach_type. Later for some of them specifying expected_attach_type 1533 * at load time became required so that program could be validated properly. 1534 * Programs of types that are allowed to be loaded both w/ and w/o (for 1535 * backward compatibility) expected_attach_type, should have the default attach 1536 * type assigned to expected_attach_type for the latter case, so that it can be 1537 * validated later at attach time. 1538 * 1539 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1540 * prog type requires it but has some attach types that have to be backward 1541 * compatible. 1542 */ 1543 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1544 { 1545 switch (attr->prog_type) { 1546 case BPF_PROG_TYPE_CGROUP_SOCK: 1547 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1548 * exist so checking for non-zero is the way to go here. 1549 */ 1550 if (!attr->expected_attach_type) 1551 attr->expected_attach_type = 1552 BPF_CGROUP_INET_SOCK_CREATE; 1553 break; 1554 } 1555 } 1556 1557 static int 1558 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type, 1559 enum bpf_attach_type expected_attach_type) 1560 { 1561 switch (prog_type) { 1562 case BPF_PROG_TYPE_CGROUP_SOCK: 1563 switch (expected_attach_type) { 1564 case BPF_CGROUP_INET_SOCK_CREATE: 1565 case BPF_CGROUP_INET4_POST_BIND: 1566 case BPF_CGROUP_INET6_POST_BIND: 1567 return 0; 1568 default: 1569 return -EINVAL; 1570 } 1571 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1572 switch (expected_attach_type) { 1573 case BPF_CGROUP_INET4_BIND: 1574 case BPF_CGROUP_INET6_BIND: 1575 case BPF_CGROUP_INET4_CONNECT: 1576 case BPF_CGROUP_INET6_CONNECT: 1577 case BPF_CGROUP_UDP4_SENDMSG: 1578 case BPF_CGROUP_UDP6_SENDMSG: 1579 case BPF_CGROUP_UDP4_RECVMSG: 1580 case BPF_CGROUP_UDP6_RECVMSG: 1581 return 0; 1582 default: 1583 return -EINVAL; 1584 } 1585 case BPF_PROG_TYPE_CGROUP_SKB: 1586 switch (expected_attach_type) { 1587 case BPF_CGROUP_INET_INGRESS: 1588 case BPF_CGROUP_INET_EGRESS: 1589 return 0; 1590 default: 1591 return -EINVAL; 1592 } 1593 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1594 switch (expected_attach_type) { 1595 case BPF_CGROUP_SETSOCKOPT: 1596 case BPF_CGROUP_GETSOCKOPT: 1597 return 0; 1598 default: 1599 return -EINVAL; 1600 } 1601 default: 1602 return 0; 1603 } 1604 } 1605 1606 /* last field in 'union bpf_attr' used by this command */ 1607 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt 1608 1609 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 1610 { 1611 enum bpf_prog_type type = attr->prog_type; 1612 struct bpf_prog *prog; 1613 int err; 1614 char license[128]; 1615 bool is_gpl; 1616 1617 if (CHECK_ATTR(BPF_PROG_LOAD)) 1618 return -EINVAL; 1619 1620 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 1621 BPF_F_ANY_ALIGNMENT | 1622 BPF_F_TEST_RND_HI32)) 1623 return -EINVAL; 1624 1625 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 1626 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 1627 !capable(CAP_SYS_ADMIN)) 1628 return -EPERM; 1629 1630 /* copy eBPF program license from user space */ 1631 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 1632 sizeof(license) - 1) < 0) 1633 return -EFAULT; 1634 license[sizeof(license) - 1] = 0; 1635 1636 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 1637 is_gpl = license_is_gpl_compatible(license); 1638 1639 if (attr->insn_cnt == 0 || 1640 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 1641 return -E2BIG; 1642 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 1643 type != BPF_PROG_TYPE_CGROUP_SKB && 1644 !capable(CAP_SYS_ADMIN)) 1645 return -EPERM; 1646 1647 bpf_prog_load_fixup_attach_type(attr); 1648 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type)) 1649 return -EINVAL; 1650 1651 /* plain bpf_prog allocation */ 1652 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 1653 if (!prog) 1654 return -ENOMEM; 1655 1656 prog->expected_attach_type = attr->expected_attach_type; 1657 1658 prog->aux->offload_requested = !!attr->prog_ifindex; 1659 1660 err = security_bpf_prog_alloc(prog->aux); 1661 if (err) 1662 goto free_prog_nouncharge; 1663 1664 err = bpf_prog_charge_memlock(prog); 1665 if (err) 1666 goto free_prog_sec; 1667 1668 prog->len = attr->insn_cnt; 1669 1670 err = -EFAULT; 1671 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 1672 bpf_prog_insn_size(prog)) != 0) 1673 goto free_prog; 1674 1675 prog->orig_prog = NULL; 1676 prog->jited = 0; 1677 1678 atomic_set(&prog->aux->refcnt, 1); 1679 prog->gpl_compatible = is_gpl ? 1 : 0; 1680 1681 if (bpf_prog_is_dev_bound(prog->aux)) { 1682 err = bpf_prog_offload_init(prog, attr); 1683 if (err) 1684 goto free_prog; 1685 } 1686 1687 /* find program type: socket_filter vs tracing_filter */ 1688 err = find_prog_type(type, prog); 1689 if (err < 0) 1690 goto free_prog; 1691 1692 prog->aux->load_time = ktime_get_boottime_ns(); 1693 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 1694 if (err) 1695 goto free_prog; 1696 1697 /* run eBPF verifier */ 1698 err = bpf_check(&prog, attr, uattr); 1699 if (err < 0) 1700 goto free_used_maps; 1701 1702 prog = bpf_prog_select_runtime(prog, &err); 1703 if (err < 0) 1704 goto free_used_maps; 1705 1706 err = bpf_prog_alloc_id(prog); 1707 if (err) 1708 goto free_used_maps; 1709 1710 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 1711 * effectively publicly exposed. However, retrieving via 1712 * bpf_prog_get_fd_by_id() will take another reference, 1713 * therefore it cannot be gone underneath us. 1714 * 1715 * Only for the time /after/ successful bpf_prog_new_fd() 1716 * and before returning to userspace, we might just hold 1717 * one reference and any parallel close on that fd could 1718 * rip everything out. Hence, below notifications must 1719 * happen before bpf_prog_new_fd(). 1720 * 1721 * Also, any failure handling from this point onwards must 1722 * be using bpf_prog_put() given the program is exposed. 1723 */ 1724 bpf_prog_kallsyms_add(prog); 1725 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 1726 1727 err = bpf_prog_new_fd(prog); 1728 if (err < 0) 1729 bpf_prog_put(prog); 1730 return err; 1731 1732 free_used_maps: 1733 bpf_prog_free_linfo(prog); 1734 kvfree(prog->aux->func_info); 1735 btf_put(prog->aux->btf); 1736 bpf_prog_kallsyms_del_subprogs(prog); 1737 free_used_maps(prog->aux); 1738 free_prog: 1739 bpf_prog_uncharge_memlock(prog); 1740 free_prog_sec: 1741 security_bpf_prog_free(prog->aux); 1742 free_prog_nouncharge: 1743 bpf_prog_free(prog); 1744 return err; 1745 } 1746 1747 #define BPF_OBJ_LAST_FIELD file_flags 1748 1749 static int bpf_obj_pin(const union bpf_attr *attr) 1750 { 1751 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 1752 return -EINVAL; 1753 1754 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 1755 } 1756 1757 static int bpf_obj_get(const union bpf_attr *attr) 1758 { 1759 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 1760 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 1761 return -EINVAL; 1762 1763 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 1764 attr->file_flags); 1765 } 1766 1767 struct bpf_raw_tracepoint { 1768 struct bpf_raw_event_map *btp; 1769 struct bpf_prog *prog; 1770 }; 1771 1772 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) 1773 { 1774 struct bpf_raw_tracepoint *raw_tp = filp->private_data; 1775 1776 if (raw_tp->prog) { 1777 bpf_probe_unregister(raw_tp->btp, raw_tp->prog); 1778 bpf_prog_put(raw_tp->prog); 1779 } 1780 bpf_put_raw_tracepoint(raw_tp->btp); 1781 kfree(raw_tp); 1782 return 0; 1783 } 1784 1785 static const struct file_operations bpf_raw_tp_fops = { 1786 .release = bpf_raw_tracepoint_release, 1787 .read = bpf_dummy_read, 1788 .write = bpf_dummy_write, 1789 }; 1790 1791 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 1792 1793 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 1794 { 1795 struct bpf_raw_tracepoint *raw_tp; 1796 struct bpf_raw_event_map *btp; 1797 struct bpf_prog *prog; 1798 char tp_name[128]; 1799 int tp_fd, err; 1800 1801 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name), 1802 sizeof(tp_name) - 1) < 0) 1803 return -EFAULT; 1804 tp_name[sizeof(tp_name) - 1] = 0; 1805 1806 btp = bpf_get_raw_tracepoint(tp_name); 1807 if (!btp) 1808 return -ENOENT; 1809 1810 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 1811 if (!raw_tp) { 1812 err = -ENOMEM; 1813 goto out_put_btp; 1814 } 1815 raw_tp->btp = btp; 1816 1817 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 1818 if (IS_ERR(prog)) { 1819 err = PTR_ERR(prog); 1820 goto out_free_tp; 1821 } 1822 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT && 1823 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) { 1824 err = -EINVAL; 1825 goto out_put_prog; 1826 } 1827 1828 err = bpf_probe_register(raw_tp->btp, prog); 1829 if (err) 1830 goto out_put_prog; 1831 1832 raw_tp->prog = prog; 1833 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp, 1834 O_CLOEXEC); 1835 if (tp_fd < 0) { 1836 bpf_probe_unregister(raw_tp->btp, prog); 1837 err = tp_fd; 1838 goto out_put_prog; 1839 } 1840 return tp_fd; 1841 1842 out_put_prog: 1843 bpf_prog_put(prog); 1844 out_free_tp: 1845 kfree(raw_tp); 1846 out_put_btp: 1847 bpf_put_raw_tracepoint(btp); 1848 return err; 1849 } 1850 1851 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 1852 enum bpf_attach_type attach_type) 1853 { 1854 switch (prog->type) { 1855 case BPF_PROG_TYPE_CGROUP_SOCK: 1856 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1857 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1858 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 1859 case BPF_PROG_TYPE_CGROUP_SKB: 1860 return prog->enforce_expected_attach_type && 1861 prog->expected_attach_type != attach_type ? 1862 -EINVAL : 0; 1863 default: 1864 return 0; 1865 } 1866 } 1867 1868 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags 1869 1870 #define BPF_F_ATTACH_MASK \ 1871 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) 1872 1873 static int bpf_prog_attach(const union bpf_attr *attr) 1874 { 1875 enum bpf_prog_type ptype; 1876 struct bpf_prog *prog; 1877 int ret; 1878 1879 if (!capable(CAP_NET_ADMIN)) 1880 return -EPERM; 1881 1882 if (CHECK_ATTR(BPF_PROG_ATTACH)) 1883 return -EINVAL; 1884 1885 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 1886 return -EINVAL; 1887 1888 switch (attr->attach_type) { 1889 case BPF_CGROUP_INET_INGRESS: 1890 case BPF_CGROUP_INET_EGRESS: 1891 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1892 break; 1893 case BPF_CGROUP_INET_SOCK_CREATE: 1894 case BPF_CGROUP_INET4_POST_BIND: 1895 case BPF_CGROUP_INET6_POST_BIND: 1896 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1897 break; 1898 case BPF_CGROUP_INET4_BIND: 1899 case BPF_CGROUP_INET6_BIND: 1900 case BPF_CGROUP_INET4_CONNECT: 1901 case BPF_CGROUP_INET6_CONNECT: 1902 case BPF_CGROUP_UDP4_SENDMSG: 1903 case BPF_CGROUP_UDP6_SENDMSG: 1904 case BPF_CGROUP_UDP4_RECVMSG: 1905 case BPF_CGROUP_UDP6_RECVMSG: 1906 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1907 break; 1908 case BPF_CGROUP_SOCK_OPS: 1909 ptype = BPF_PROG_TYPE_SOCK_OPS; 1910 break; 1911 case BPF_CGROUP_DEVICE: 1912 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1913 break; 1914 case BPF_SK_MSG_VERDICT: 1915 ptype = BPF_PROG_TYPE_SK_MSG; 1916 break; 1917 case BPF_SK_SKB_STREAM_PARSER: 1918 case BPF_SK_SKB_STREAM_VERDICT: 1919 ptype = BPF_PROG_TYPE_SK_SKB; 1920 break; 1921 case BPF_LIRC_MODE2: 1922 ptype = BPF_PROG_TYPE_LIRC_MODE2; 1923 break; 1924 case BPF_FLOW_DISSECTOR: 1925 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR; 1926 break; 1927 case BPF_CGROUP_SYSCTL: 1928 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 1929 break; 1930 case BPF_CGROUP_GETSOCKOPT: 1931 case BPF_CGROUP_SETSOCKOPT: 1932 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 1933 break; 1934 default: 1935 return -EINVAL; 1936 } 1937 1938 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1939 if (IS_ERR(prog)) 1940 return PTR_ERR(prog); 1941 1942 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 1943 bpf_prog_put(prog); 1944 return -EINVAL; 1945 } 1946 1947 switch (ptype) { 1948 case BPF_PROG_TYPE_SK_SKB: 1949 case BPF_PROG_TYPE_SK_MSG: 1950 ret = sock_map_get_from_fd(attr, prog); 1951 break; 1952 case BPF_PROG_TYPE_LIRC_MODE2: 1953 ret = lirc_prog_attach(attr, prog); 1954 break; 1955 case BPF_PROG_TYPE_FLOW_DISSECTOR: 1956 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 1957 break; 1958 default: 1959 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 1960 } 1961 1962 if (ret) 1963 bpf_prog_put(prog); 1964 return ret; 1965 } 1966 1967 #define BPF_PROG_DETACH_LAST_FIELD attach_type 1968 1969 static int bpf_prog_detach(const union bpf_attr *attr) 1970 { 1971 enum bpf_prog_type ptype; 1972 1973 if (!capable(CAP_NET_ADMIN)) 1974 return -EPERM; 1975 1976 if (CHECK_ATTR(BPF_PROG_DETACH)) 1977 return -EINVAL; 1978 1979 switch (attr->attach_type) { 1980 case BPF_CGROUP_INET_INGRESS: 1981 case BPF_CGROUP_INET_EGRESS: 1982 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1983 break; 1984 case BPF_CGROUP_INET_SOCK_CREATE: 1985 case BPF_CGROUP_INET4_POST_BIND: 1986 case BPF_CGROUP_INET6_POST_BIND: 1987 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1988 break; 1989 case BPF_CGROUP_INET4_BIND: 1990 case BPF_CGROUP_INET6_BIND: 1991 case BPF_CGROUP_INET4_CONNECT: 1992 case BPF_CGROUP_INET6_CONNECT: 1993 case BPF_CGROUP_UDP4_SENDMSG: 1994 case BPF_CGROUP_UDP6_SENDMSG: 1995 case BPF_CGROUP_UDP4_RECVMSG: 1996 case BPF_CGROUP_UDP6_RECVMSG: 1997 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1998 break; 1999 case BPF_CGROUP_SOCK_OPS: 2000 ptype = BPF_PROG_TYPE_SOCK_OPS; 2001 break; 2002 case BPF_CGROUP_DEVICE: 2003 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 2004 break; 2005 case BPF_SK_MSG_VERDICT: 2006 return sock_map_get_from_fd(attr, NULL); 2007 case BPF_SK_SKB_STREAM_PARSER: 2008 case BPF_SK_SKB_STREAM_VERDICT: 2009 return sock_map_get_from_fd(attr, NULL); 2010 case BPF_LIRC_MODE2: 2011 return lirc_prog_detach(attr); 2012 case BPF_FLOW_DISSECTOR: 2013 return skb_flow_dissector_bpf_prog_detach(attr); 2014 case BPF_CGROUP_SYSCTL: 2015 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 2016 break; 2017 case BPF_CGROUP_GETSOCKOPT: 2018 case BPF_CGROUP_SETSOCKOPT: 2019 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 2020 break; 2021 default: 2022 return -EINVAL; 2023 } 2024 2025 return cgroup_bpf_prog_detach(attr, ptype); 2026 } 2027 2028 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 2029 2030 static int bpf_prog_query(const union bpf_attr *attr, 2031 union bpf_attr __user *uattr) 2032 { 2033 if (!capable(CAP_NET_ADMIN)) 2034 return -EPERM; 2035 if (CHECK_ATTR(BPF_PROG_QUERY)) 2036 return -EINVAL; 2037 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2038 return -EINVAL; 2039 2040 switch (attr->query.attach_type) { 2041 case BPF_CGROUP_INET_INGRESS: 2042 case BPF_CGROUP_INET_EGRESS: 2043 case BPF_CGROUP_INET_SOCK_CREATE: 2044 case BPF_CGROUP_INET4_BIND: 2045 case BPF_CGROUP_INET6_BIND: 2046 case BPF_CGROUP_INET4_POST_BIND: 2047 case BPF_CGROUP_INET6_POST_BIND: 2048 case BPF_CGROUP_INET4_CONNECT: 2049 case BPF_CGROUP_INET6_CONNECT: 2050 case BPF_CGROUP_UDP4_SENDMSG: 2051 case BPF_CGROUP_UDP6_SENDMSG: 2052 case BPF_CGROUP_UDP4_RECVMSG: 2053 case BPF_CGROUP_UDP6_RECVMSG: 2054 case BPF_CGROUP_SOCK_OPS: 2055 case BPF_CGROUP_DEVICE: 2056 case BPF_CGROUP_SYSCTL: 2057 case BPF_CGROUP_GETSOCKOPT: 2058 case BPF_CGROUP_SETSOCKOPT: 2059 break; 2060 case BPF_LIRC_MODE2: 2061 return lirc_prog_query(attr, uattr); 2062 case BPF_FLOW_DISSECTOR: 2063 return skb_flow_dissector_prog_query(attr, uattr); 2064 default: 2065 return -EINVAL; 2066 } 2067 2068 return cgroup_bpf_prog_query(attr, uattr); 2069 } 2070 2071 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2072 2073 static int bpf_prog_test_run(const union bpf_attr *attr, 2074 union bpf_attr __user *uattr) 2075 { 2076 struct bpf_prog *prog; 2077 int ret = -ENOTSUPP; 2078 2079 if (!capable(CAP_SYS_ADMIN)) 2080 return -EPERM; 2081 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2082 return -EINVAL; 2083 2084 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2085 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2086 return -EINVAL; 2087 2088 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2089 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2090 return -EINVAL; 2091 2092 prog = bpf_prog_get(attr->test.prog_fd); 2093 if (IS_ERR(prog)) 2094 return PTR_ERR(prog); 2095 2096 if (prog->aux->ops->test_run) 2097 ret = prog->aux->ops->test_run(prog, attr, uattr); 2098 2099 bpf_prog_put(prog); 2100 return ret; 2101 } 2102 2103 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2104 2105 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2106 union bpf_attr __user *uattr, 2107 struct idr *idr, 2108 spinlock_t *lock) 2109 { 2110 u32 next_id = attr->start_id; 2111 int err = 0; 2112 2113 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2114 return -EINVAL; 2115 2116 if (!capable(CAP_SYS_ADMIN)) 2117 return -EPERM; 2118 2119 next_id++; 2120 spin_lock_bh(lock); 2121 if (!idr_get_next(idr, &next_id)) 2122 err = -ENOENT; 2123 spin_unlock_bh(lock); 2124 2125 if (!err) 2126 err = put_user(next_id, &uattr->next_id); 2127 2128 return err; 2129 } 2130 2131 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2132 2133 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2134 { 2135 struct bpf_prog *prog; 2136 u32 id = attr->prog_id; 2137 int fd; 2138 2139 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2140 return -EINVAL; 2141 2142 if (!capable(CAP_SYS_ADMIN)) 2143 return -EPERM; 2144 2145 spin_lock_bh(&prog_idr_lock); 2146 prog = idr_find(&prog_idr, id); 2147 if (prog) 2148 prog = bpf_prog_inc_not_zero(prog); 2149 else 2150 prog = ERR_PTR(-ENOENT); 2151 spin_unlock_bh(&prog_idr_lock); 2152 2153 if (IS_ERR(prog)) 2154 return PTR_ERR(prog); 2155 2156 fd = bpf_prog_new_fd(prog); 2157 if (fd < 0) 2158 bpf_prog_put(prog); 2159 2160 return fd; 2161 } 2162 2163 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2164 2165 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2166 { 2167 struct bpf_map *map; 2168 u32 id = attr->map_id; 2169 int f_flags; 2170 int fd; 2171 2172 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2173 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2174 return -EINVAL; 2175 2176 if (!capable(CAP_SYS_ADMIN)) 2177 return -EPERM; 2178 2179 f_flags = bpf_get_file_flag(attr->open_flags); 2180 if (f_flags < 0) 2181 return f_flags; 2182 2183 spin_lock_bh(&map_idr_lock); 2184 map = idr_find(&map_idr, id); 2185 if (map) 2186 map = bpf_map_inc_not_zero(map, true); 2187 else 2188 map = ERR_PTR(-ENOENT); 2189 spin_unlock_bh(&map_idr_lock); 2190 2191 if (IS_ERR(map)) 2192 return PTR_ERR(map); 2193 2194 fd = bpf_map_new_fd(map, f_flags); 2195 if (fd < 0) 2196 bpf_map_put_with_uref(map); 2197 2198 return fd; 2199 } 2200 2201 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2202 unsigned long addr, u32 *off, 2203 u32 *type) 2204 { 2205 const struct bpf_map *map; 2206 int i; 2207 2208 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2209 map = prog->aux->used_maps[i]; 2210 if (map == (void *)addr) { 2211 *type = BPF_PSEUDO_MAP_FD; 2212 return map; 2213 } 2214 if (!map->ops->map_direct_value_meta) 2215 continue; 2216 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2217 *type = BPF_PSEUDO_MAP_VALUE; 2218 return map; 2219 } 2220 } 2221 2222 return NULL; 2223 } 2224 2225 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2226 { 2227 const struct bpf_map *map; 2228 struct bpf_insn *insns; 2229 u32 off, type; 2230 u64 imm; 2231 int i; 2232 2233 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2234 GFP_USER); 2235 if (!insns) 2236 return insns; 2237 2238 for (i = 0; i < prog->len; i++) { 2239 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2240 insns[i].code = BPF_JMP | BPF_CALL; 2241 insns[i].imm = BPF_FUNC_tail_call; 2242 /* fall-through */ 2243 } 2244 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2245 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2246 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2247 insns[i].code = BPF_JMP | BPF_CALL; 2248 if (!bpf_dump_raw_ok()) 2249 insns[i].imm = 0; 2250 continue; 2251 } 2252 2253 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2254 continue; 2255 2256 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2257 map = bpf_map_from_imm(prog, imm, &off, &type); 2258 if (map) { 2259 insns[i].src_reg = type; 2260 insns[i].imm = map->id; 2261 insns[i + 1].imm = off; 2262 continue; 2263 } 2264 } 2265 2266 return insns; 2267 } 2268 2269 static int set_info_rec_size(struct bpf_prog_info *info) 2270 { 2271 /* 2272 * Ensure info.*_rec_size is the same as kernel expected size 2273 * 2274 * or 2275 * 2276 * Only allow zero *_rec_size if both _rec_size and _cnt are 2277 * zero. In this case, the kernel will set the expected 2278 * _rec_size back to the info. 2279 */ 2280 2281 if ((info->nr_func_info || info->func_info_rec_size) && 2282 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2283 return -EINVAL; 2284 2285 if ((info->nr_line_info || info->line_info_rec_size) && 2286 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2287 return -EINVAL; 2288 2289 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2290 info->jited_line_info_rec_size != sizeof(__u64)) 2291 return -EINVAL; 2292 2293 info->func_info_rec_size = sizeof(struct bpf_func_info); 2294 info->line_info_rec_size = sizeof(struct bpf_line_info); 2295 info->jited_line_info_rec_size = sizeof(__u64); 2296 2297 return 0; 2298 } 2299 2300 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2301 const union bpf_attr *attr, 2302 union bpf_attr __user *uattr) 2303 { 2304 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2305 struct bpf_prog_info info = {}; 2306 u32 info_len = attr->info.info_len; 2307 struct bpf_prog_stats stats; 2308 char __user *uinsns; 2309 u32 ulen; 2310 int err; 2311 2312 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2313 if (err) 2314 return err; 2315 info_len = min_t(u32, sizeof(info), info_len); 2316 2317 if (copy_from_user(&info, uinfo, info_len)) 2318 return -EFAULT; 2319 2320 info.type = prog->type; 2321 info.id = prog->aux->id; 2322 info.load_time = prog->aux->load_time; 2323 info.created_by_uid = from_kuid_munged(current_user_ns(), 2324 prog->aux->user->uid); 2325 info.gpl_compatible = prog->gpl_compatible; 2326 2327 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 2328 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 2329 2330 ulen = info.nr_map_ids; 2331 info.nr_map_ids = prog->aux->used_map_cnt; 2332 ulen = min_t(u32, info.nr_map_ids, ulen); 2333 if (ulen) { 2334 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 2335 u32 i; 2336 2337 for (i = 0; i < ulen; i++) 2338 if (put_user(prog->aux->used_maps[i]->id, 2339 &user_map_ids[i])) 2340 return -EFAULT; 2341 } 2342 2343 err = set_info_rec_size(&info); 2344 if (err) 2345 return err; 2346 2347 bpf_prog_get_stats(prog, &stats); 2348 info.run_time_ns = stats.nsecs; 2349 info.run_cnt = stats.cnt; 2350 2351 if (!capable(CAP_SYS_ADMIN)) { 2352 info.jited_prog_len = 0; 2353 info.xlated_prog_len = 0; 2354 info.nr_jited_ksyms = 0; 2355 info.nr_jited_func_lens = 0; 2356 info.nr_func_info = 0; 2357 info.nr_line_info = 0; 2358 info.nr_jited_line_info = 0; 2359 goto done; 2360 } 2361 2362 ulen = info.xlated_prog_len; 2363 info.xlated_prog_len = bpf_prog_insn_size(prog); 2364 if (info.xlated_prog_len && ulen) { 2365 struct bpf_insn *insns_sanitized; 2366 bool fault; 2367 2368 if (prog->blinded && !bpf_dump_raw_ok()) { 2369 info.xlated_prog_insns = 0; 2370 goto done; 2371 } 2372 insns_sanitized = bpf_insn_prepare_dump(prog); 2373 if (!insns_sanitized) 2374 return -ENOMEM; 2375 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 2376 ulen = min_t(u32, info.xlated_prog_len, ulen); 2377 fault = copy_to_user(uinsns, insns_sanitized, ulen); 2378 kfree(insns_sanitized); 2379 if (fault) 2380 return -EFAULT; 2381 } 2382 2383 if (bpf_prog_is_dev_bound(prog->aux)) { 2384 err = bpf_prog_offload_info_fill(&info, prog); 2385 if (err) 2386 return err; 2387 goto done; 2388 } 2389 2390 /* NOTE: the following code is supposed to be skipped for offload. 2391 * bpf_prog_offload_info_fill() is the place to fill similar fields 2392 * for offload. 2393 */ 2394 ulen = info.jited_prog_len; 2395 if (prog->aux->func_cnt) { 2396 u32 i; 2397 2398 info.jited_prog_len = 0; 2399 for (i = 0; i < prog->aux->func_cnt; i++) 2400 info.jited_prog_len += prog->aux->func[i]->jited_len; 2401 } else { 2402 info.jited_prog_len = prog->jited_len; 2403 } 2404 2405 if (info.jited_prog_len && ulen) { 2406 if (bpf_dump_raw_ok()) { 2407 uinsns = u64_to_user_ptr(info.jited_prog_insns); 2408 ulen = min_t(u32, info.jited_prog_len, ulen); 2409 2410 /* for multi-function programs, copy the JITed 2411 * instructions for all the functions 2412 */ 2413 if (prog->aux->func_cnt) { 2414 u32 len, free, i; 2415 u8 *img; 2416 2417 free = ulen; 2418 for (i = 0; i < prog->aux->func_cnt; i++) { 2419 len = prog->aux->func[i]->jited_len; 2420 len = min_t(u32, len, free); 2421 img = (u8 *) prog->aux->func[i]->bpf_func; 2422 if (copy_to_user(uinsns, img, len)) 2423 return -EFAULT; 2424 uinsns += len; 2425 free -= len; 2426 if (!free) 2427 break; 2428 } 2429 } else { 2430 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 2431 return -EFAULT; 2432 } 2433 } else { 2434 info.jited_prog_insns = 0; 2435 } 2436 } 2437 2438 ulen = info.nr_jited_ksyms; 2439 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 2440 if (ulen) { 2441 if (bpf_dump_raw_ok()) { 2442 unsigned long ksym_addr; 2443 u64 __user *user_ksyms; 2444 u32 i; 2445 2446 /* copy the address of the kernel symbol 2447 * corresponding to each function 2448 */ 2449 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 2450 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 2451 if (prog->aux->func_cnt) { 2452 for (i = 0; i < ulen; i++) { 2453 ksym_addr = (unsigned long) 2454 prog->aux->func[i]->bpf_func; 2455 if (put_user((u64) ksym_addr, 2456 &user_ksyms[i])) 2457 return -EFAULT; 2458 } 2459 } else { 2460 ksym_addr = (unsigned long) prog->bpf_func; 2461 if (put_user((u64) ksym_addr, &user_ksyms[0])) 2462 return -EFAULT; 2463 } 2464 } else { 2465 info.jited_ksyms = 0; 2466 } 2467 } 2468 2469 ulen = info.nr_jited_func_lens; 2470 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 2471 if (ulen) { 2472 if (bpf_dump_raw_ok()) { 2473 u32 __user *user_lens; 2474 u32 func_len, i; 2475 2476 /* copy the JITed image lengths for each function */ 2477 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 2478 user_lens = u64_to_user_ptr(info.jited_func_lens); 2479 if (prog->aux->func_cnt) { 2480 for (i = 0; i < ulen; i++) { 2481 func_len = 2482 prog->aux->func[i]->jited_len; 2483 if (put_user(func_len, &user_lens[i])) 2484 return -EFAULT; 2485 } 2486 } else { 2487 func_len = prog->jited_len; 2488 if (put_user(func_len, &user_lens[0])) 2489 return -EFAULT; 2490 } 2491 } else { 2492 info.jited_func_lens = 0; 2493 } 2494 } 2495 2496 if (prog->aux->btf) 2497 info.btf_id = btf_id(prog->aux->btf); 2498 2499 ulen = info.nr_func_info; 2500 info.nr_func_info = prog->aux->func_info_cnt; 2501 if (info.nr_func_info && ulen) { 2502 char __user *user_finfo; 2503 2504 user_finfo = u64_to_user_ptr(info.func_info); 2505 ulen = min_t(u32, info.nr_func_info, ulen); 2506 if (copy_to_user(user_finfo, prog->aux->func_info, 2507 info.func_info_rec_size * ulen)) 2508 return -EFAULT; 2509 } 2510 2511 ulen = info.nr_line_info; 2512 info.nr_line_info = prog->aux->nr_linfo; 2513 if (info.nr_line_info && ulen) { 2514 __u8 __user *user_linfo; 2515 2516 user_linfo = u64_to_user_ptr(info.line_info); 2517 ulen = min_t(u32, info.nr_line_info, ulen); 2518 if (copy_to_user(user_linfo, prog->aux->linfo, 2519 info.line_info_rec_size * ulen)) 2520 return -EFAULT; 2521 } 2522 2523 ulen = info.nr_jited_line_info; 2524 if (prog->aux->jited_linfo) 2525 info.nr_jited_line_info = prog->aux->nr_linfo; 2526 else 2527 info.nr_jited_line_info = 0; 2528 if (info.nr_jited_line_info && ulen) { 2529 if (bpf_dump_raw_ok()) { 2530 __u64 __user *user_linfo; 2531 u32 i; 2532 2533 user_linfo = u64_to_user_ptr(info.jited_line_info); 2534 ulen = min_t(u32, info.nr_jited_line_info, ulen); 2535 for (i = 0; i < ulen; i++) { 2536 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 2537 &user_linfo[i])) 2538 return -EFAULT; 2539 } 2540 } else { 2541 info.jited_line_info = 0; 2542 } 2543 } 2544 2545 ulen = info.nr_prog_tags; 2546 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 2547 if (ulen) { 2548 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 2549 u32 i; 2550 2551 user_prog_tags = u64_to_user_ptr(info.prog_tags); 2552 ulen = min_t(u32, info.nr_prog_tags, ulen); 2553 if (prog->aux->func_cnt) { 2554 for (i = 0; i < ulen; i++) { 2555 if (copy_to_user(user_prog_tags[i], 2556 prog->aux->func[i]->tag, 2557 BPF_TAG_SIZE)) 2558 return -EFAULT; 2559 } 2560 } else { 2561 if (copy_to_user(user_prog_tags[0], 2562 prog->tag, BPF_TAG_SIZE)) 2563 return -EFAULT; 2564 } 2565 } 2566 2567 done: 2568 if (copy_to_user(uinfo, &info, info_len) || 2569 put_user(info_len, &uattr->info.info_len)) 2570 return -EFAULT; 2571 2572 return 0; 2573 } 2574 2575 static int bpf_map_get_info_by_fd(struct bpf_map *map, 2576 const union bpf_attr *attr, 2577 union bpf_attr __user *uattr) 2578 { 2579 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2580 struct bpf_map_info info = {}; 2581 u32 info_len = attr->info.info_len; 2582 int err; 2583 2584 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2585 if (err) 2586 return err; 2587 info_len = min_t(u32, sizeof(info), info_len); 2588 2589 info.type = map->map_type; 2590 info.id = map->id; 2591 info.key_size = map->key_size; 2592 info.value_size = map->value_size; 2593 info.max_entries = map->max_entries; 2594 info.map_flags = map->map_flags; 2595 memcpy(info.name, map->name, sizeof(map->name)); 2596 2597 if (map->btf) { 2598 info.btf_id = btf_id(map->btf); 2599 info.btf_key_type_id = map->btf_key_type_id; 2600 info.btf_value_type_id = map->btf_value_type_id; 2601 } 2602 2603 if (bpf_map_is_dev_bound(map)) { 2604 err = bpf_map_offload_info_fill(&info, map); 2605 if (err) 2606 return err; 2607 } 2608 2609 if (copy_to_user(uinfo, &info, info_len) || 2610 put_user(info_len, &uattr->info.info_len)) 2611 return -EFAULT; 2612 2613 return 0; 2614 } 2615 2616 static int bpf_btf_get_info_by_fd(struct btf *btf, 2617 const union bpf_attr *attr, 2618 union bpf_attr __user *uattr) 2619 { 2620 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2621 u32 info_len = attr->info.info_len; 2622 int err; 2623 2624 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 2625 if (err) 2626 return err; 2627 2628 return btf_get_info_by_fd(btf, attr, uattr); 2629 } 2630 2631 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 2632 2633 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 2634 union bpf_attr __user *uattr) 2635 { 2636 int ufd = attr->info.bpf_fd; 2637 struct fd f; 2638 int err; 2639 2640 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 2641 return -EINVAL; 2642 2643 f = fdget(ufd); 2644 if (!f.file) 2645 return -EBADFD; 2646 2647 if (f.file->f_op == &bpf_prog_fops) 2648 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 2649 uattr); 2650 else if (f.file->f_op == &bpf_map_fops) 2651 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 2652 uattr); 2653 else if (f.file->f_op == &btf_fops) 2654 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 2655 else 2656 err = -EINVAL; 2657 2658 fdput(f); 2659 return err; 2660 } 2661 2662 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 2663 2664 static int bpf_btf_load(const union bpf_attr *attr) 2665 { 2666 if (CHECK_ATTR(BPF_BTF_LOAD)) 2667 return -EINVAL; 2668 2669 if (!capable(CAP_SYS_ADMIN)) 2670 return -EPERM; 2671 2672 return btf_new_fd(attr); 2673 } 2674 2675 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 2676 2677 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 2678 { 2679 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 2680 return -EINVAL; 2681 2682 if (!capable(CAP_SYS_ADMIN)) 2683 return -EPERM; 2684 2685 return btf_get_fd_by_id(attr->btf_id); 2686 } 2687 2688 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 2689 union bpf_attr __user *uattr, 2690 u32 prog_id, u32 fd_type, 2691 const char *buf, u64 probe_offset, 2692 u64 probe_addr) 2693 { 2694 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 2695 u32 len = buf ? strlen(buf) : 0, input_len; 2696 int err = 0; 2697 2698 if (put_user(len, &uattr->task_fd_query.buf_len)) 2699 return -EFAULT; 2700 input_len = attr->task_fd_query.buf_len; 2701 if (input_len && ubuf) { 2702 if (!len) { 2703 /* nothing to copy, just make ubuf NULL terminated */ 2704 char zero = '\0'; 2705 2706 if (put_user(zero, ubuf)) 2707 return -EFAULT; 2708 } else if (input_len >= len + 1) { 2709 /* ubuf can hold the string with NULL terminator */ 2710 if (copy_to_user(ubuf, buf, len + 1)) 2711 return -EFAULT; 2712 } else { 2713 /* ubuf cannot hold the string with NULL terminator, 2714 * do a partial copy with NULL terminator. 2715 */ 2716 char zero = '\0'; 2717 2718 err = -ENOSPC; 2719 if (copy_to_user(ubuf, buf, input_len - 1)) 2720 return -EFAULT; 2721 if (put_user(zero, ubuf + input_len - 1)) 2722 return -EFAULT; 2723 } 2724 } 2725 2726 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 2727 put_user(fd_type, &uattr->task_fd_query.fd_type) || 2728 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 2729 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 2730 return -EFAULT; 2731 2732 return err; 2733 } 2734 2735 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 2736 2737 static int bpf_task_fd_query(const union bpf_attr *attr, 2738 union bpf_attr __user *uattr) 2739 { 2740 pid_t pid = attr->task_fd_query.pid; 2741 u32 fd = attr->task_fd_query.fd; 2742 const struct perf_event *event; 2743 struct files_struct *files; 2744 struct task_struct *task; 2745 struct file *file; 2746 int err; 2747 2748 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 2749 return -EINVAL; 2750 2751 if (!capable(CAP_SYS_ADMIN)) 2752 return -EPERM; 2753 2754 if (attr->task_fd_query.flags != 0) 2755 return -EINVAL; 2756 2757 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 2758 if (!task) 2759 return -ENOENT; 2760 2761 files = get_files_struct(task); 2762 put_task_struct(task); 2763 if (!files) 2764 return -ENOENT; 2765 2766 err = 0; 2767 spin_lock(&files->file_lock); 2768 file = fcheck_files(files, fd); 2769 if (!file) 2770 err = -EBADF; 2771 else 2772 get_file(file); 2773 spin_unlock(&files->file_lock); 2774 put_files_struct(files); 2775 2776 if (err) 2777 goto out; 2778 2779 if (file->f_op == &bpf_raw_tp_fops) { 2780 struct bpf_raw_tracepoint *raw_tp = file->private_data; 2781 struct bpf_raw_event_map *btp = raw_tp->btp; 2782 2783 err = bpf_task_fd_query_copy(attr, uattr, 2784 raw_tp->prog->aux->id, 2785 BPF_FD_TYPE_RAW_TRACEPOINT, 2786 btp->tp->name, 0, 0); 2787 goto put_file; 2788 } 2789 2790 event = perf_get_event(file); 2791 if (!IS_ERR(event)) { 2792 u64 probe_offset, probe_addr; 2793 u32 prog_id, fd_type; 2794 const char *buf; 2795 2796 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 2797 &buf, &probe_offset, 2798 &probe_addr); 2799 if (!err) 2800 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 2801 fd_type, buf, 2802 probe_offset, 2803 probe_addr); 2804 goto put_file; 2805 } 2806 2807 err = -ENOTSUPP; 2808 put_file: 2809 fput(file); 2810 out: 2811 return err; 2812 } 2813 2814 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 2815 { 2816 union bpf_attr attr = {}; 2817 int err; 2818 2819 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 2820 return -EPERM; 2821 2822 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 2823 if (err) 2824 return err; 2825 size = min_t(u32, size, sizeof(attr)); 2826 2827 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 2828 if (copy_from_user(&attr, uattr, size) != 0) 2829 return -EFAULT; 2830 2831 err = security_bpf(cmd, &attr, size); 2832 if (err < 0) 2833 return err; 2834 2835 switch (cmd) { 2836 case BPF_MAP_CREATE: 2837 err = map_create(&attr); 2838 break; 2839 case BPF_MAP_LOOKUP_ELEM: 2840 err = map_lookup_elem(&attr); 2841 break; 2842 case BPF_MAP_UPDATE_ELEM: 2843 err = map_update_elem(&attr); 2844 break; 2845 case BPF_MAP_DELETE_ELEM: 2846 err = map_delete_elem(&attr); 2847 break; 2848 case BPF_MAP_GET_NEXT_KEY: 2849 err = map_get_next_key(&attr); 2850 break; 2851 case BPF_MAP_FREEZE: 2852 err = map_freeze(&attr); 2853 break; 2854 case BPF_PROG_LOAD: 2855 err = bpf_prog_load(&attr, uattr); 2856 break; 2857 case BPF_OBJ_PIN: 2858 err = bpf_obj_pin(&attr); 2859 break; 2860 case BPF_OBJ_GET: 2861 err = bpf_obj_get(&attr); 2862 break; 2863 case BPF_PROG_ATTACH: 2864 err = bpf_prog_attach(&attr); 2865 break; 2866 case BPF_PROG_DETACH: 2867 err = bpf_prog_detach(&attr); 2868 break; 2869 case BPF_PROG_QUERY: 2870 err = bpf_prog_query(&attr, uattr); 2871 break; 2872 case BPF_PROG_TEST_RUN: 2873 err = bpf_prog_test_run(&attr, uattr); 2874 break; 2875 case BPF_PROG_GET_NEXT_ID: 2876 err = bpf_obj_get_next_id(&attr, uattr, 2877 &prog_idr, &prog_idr_lock); 2878 break; 2879 case BPF_MAP_GET_NEXT_ID: 2880 err = bpf_obj_get_next_id(&attr, uattr, 2881 &map_idr, &map_idr_lock); 2882 break; 2883 case BPF_PROG_GET_FD_BY_ID: 2884 err = bpf_prog_get_fd_by_id(&attr); 2885 break; 2886 case BPF_MAP_GET_FD_BY_ID: 2887 err = bpf_map_get_fd_by_id(&attr); 2888 break; 2889 case BPF_OBJ_GET_INFO_BY_FD: 2890 err = bpf_obj_get_info_by_fd(&attr, uattr); 2891 break; 2892 case BPF_RAW_TRACEPOINT_OPEN: 2893 err = bpf_raw_tracepoint_open(&attr); 2894 break; 2895 case BPF_BTF_LOAD: 2896 err = bpf_btf_load(&attr); 2897 break; 2898 case BPF_BTF_GET_FD_BY_ID: 2899 err = bpf_btf_get_fd_by_id(&attr); 2900 break; 2901 case BPF_TASK_FD_QUERY: 2902 err = bpf_task_fd_query(&attr, uattr); 2903 break; 2904 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 2905 err = map_lookup_and_delete_elem(&attr); 2906 break; 2907 default: 2908 err = -EINVAL; 2909 break; 2910 } 2911 2912 return err; 2913 } 2914