1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 2 * 3 * This program is free software; you can redistribute it and/or 4 * modify it under the terms of version 2 of the GNU General Public 5 * License as published by the Free Software Foundation. 6 * 7 * This program is distributed in the hope that it will be useful, but 8 * WITHOUT ANY WARRANTY; without even the implied warranty of 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 10 * General Public License for more details. 11 */ 12 #include <linux/bpf.h> 13 #include <linux/bpf_trace.h> 14 #include <linux/btf.h> 15 #include <linux/syscalls.h> 16 #include <linux/slab.h> 17 #include <linux/sched/signal.h> 18 #include <linux/vmalloc.h> 19 #include <linux/mmzone.h> 20 #include <linux/anon_inodes.h> 21 #include <linux/fdtable.h> 22 #include <linux/file.h> 23 #include <linux/fs.h> 24 #include <linux/license.h> 25 #include <linux/filter.h> 26 #include <linux/version.h> 27 #include <linux/kernel.h> 28 #include <linux/idr.h> 29 #include <linux/cred.h> 30 #include <linux/timekeeping.h> 31 #include <linux/ctype.h> 32 #include <linux/btf.h> 33 #include <linux/nospec.h> 34 35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \ 36 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 37 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 38 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 39 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map)) 41 42 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 43 44 DEFINE_PER_CPU(int, bpf_prog_active); 45 static DEFINE_IDR(prog_idr); 46 static DEFINE_SPINLOCK(prog_idr_lock); 47 static DEFINE_IDR(map_idr); 48 static DEFINE_SPINLOCK(map_idr_lock); 49 50 int sysctl_unprivileged_bpf_disabled __read_mostly; 51 52 static const struct bpf_map_ops * const bpf_map_types[] = { 53 #define BPF_PROG_TYPE(_id, _ops) 54 #define BPF_MAP_TYPE(_id, _ops) \ 55 [_id] = &_ops, 56 #include <linux/bpf_types.h> 57 #undef BPF_PROG_TYPE 58 #undef BPF_MAP_TYPE 59 }; 60 61 /* 62 * If we're handed a bigger struct than we know of, ensure all the unknown bits 63 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 64 * we don't know about yet. 65 * 66 * There is a ToCToU between this function call and the following 67 * copy_from_user() call. However, this is not a concern since this function is 68 * meant to be a future-proofing of bits. 69 */ 70 int bpf_check_uarg_tail_zero(void __user *uaddr, 71 size_t expected_size, 72 size_t actual_size) 73 { 74 unsigned char __user *addr; 75 unsigned char __user *end; 76 unsigned char val; 77 int err; 78 79 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 80 return -E2BIG; 81 82 if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size))) 83 return -EFAULT; 84 85 if (actual_size <= expected_size) 86 return 0; 87 88 addr = uaddr + expected_size; 89 end = uaddr + actual_size; 90 91 for (; addr < end; addr++) { 92 err = get_user(val, addr); 93 if (err) 94 return err; 95 if (val) 96 return -E2BIG; 97 } 98 99 return 0; 100 } 101 102 const struct bpf_map_ops bpf_map_offload_ops = { 103 .map_alloc = bpf_map_offload_map_alloc, 104 .map_free = bpf_map_offload_map_free, 105 }; 106 107 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 108 { 109 const struct bpf_map_ops *ops; 110 u32 type = attr->map_type; 111 struct bpf_map *map; 112 int err; 113 114 if (type >= ARRAY_SIZE(bpf_map_types)) 115 return ERR_PTR(-EINVAL); 116 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 117 ops = bpf_map_types[type]; 118 if (!ops) 119 return ERR_PTR(-EINVAL); 120 121 if (ops->map_alloc_check) { 122 err = ops->map_alloc_check(attr); 123 if (err) 124 return ERR_PTR(err); 125 } 126 if (attr->map_ifindex) 127 ops = &bpf_map_offload_ops; 128 map = ops->map_alloc(attr); 129 if (IS_ERR(map)) 130 return map; 131 map->ops = ops; 132 map->map_type = type; 133 return map; 134 } 135 136 void *bpf_map_area_alloc(size_t size, int numa_node) 137 { 138 /* We definitely need __GFP_NORETRY, so OOM killer doesn't 139 * trigger under memory pressure as we really just want to 140 * fail instead. 141 */ 142 const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO; 143 void *area; 144 145 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 146 area = kmalloc_node(size, GFP_USER | flags, numa_node); 147 if (area != NULL) 148 return area; 149 } 150 151 return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags, 152 __builtin_return_address(0)); 153 } 154 155 void bpf_map_area_free(void *area) 156 { 157 kvfree(area); 158 } 159 160 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 161 { 162 map->map_type = attr->map_type; 163 map->key_size = attr->key_size; 164 map->value_size = attr->value_size; 165 map->max_entries = attr->max_entries; 166 map->map_flags = attr->map_flags; 167 map->numa_node = bpf_map_attr_numa_node(attr); 168 } 169 170 int bpf_map_precharge_memlock(u32 pages) 171 { 172 struct user_struct *user = get_current_user(); 173 unsigned long memlock_limit, cur; 174 175 memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 176 cur = atomic_long_read(&user->locked_vm); 177 free_uid(user); 178 if (cur + pages > memlock_limit) 179 return -EPERM; 180 return 0; 181 } 182 183 static int bpf_map_charge_memlock(struct bpf_map *map) 184 { 185 struct user_struct *user = get_current_user(); 186 unsigned long memlock_limit; 187 188 memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 189 190 atomic_long_add(map->pages, &user->locked_vm); 191 192 if (atomic_long_read(&user->locked_vm) > memlock_limit) { 193 atomic_long_sub(map->pages, &user->locked_vm); 194 free_uid(user); 195 return -EPERM; 196 } 197 map->user = user; 198 return 0; 199 } 200 201 static void bpf_map_uncharge_memlock(struct bpf_map *map) 202 { 203 struct user_struct *user = map->user; 204 205 atomic_long_sub(map->pages, &user->locked_vm); 206 free_uid(user); 207 } 208 209 static int bpf_map_alloc_id(struct bpf_map *map) 210 { 211 int id; 212 213 idr_preload(GFP_KERNEL); 214 spin_lock_bh(&map_idr_lock); 215 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 216 if (id > 0) 217 map->id = id; 218 spin_unlock_bh(&map_idr_lock); 219 idr_preload_end(); 220 221 if (WARN_ON_ONCE(!id)) 222 return -ENOSPC; 223 224 return id > 0 ? 0 : id; 225 } 226 227 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 228 { 229 unsigned long flags; 230 231 /* Offloaded maps are removed from the IDR store when their device 232 * disappears - even if someone holds an fd to them they are unusable, 233 * the memory is gone, all ops will fail; they are simply waiting for 234 * refcnt to drop to be freed. 235 */ 236 if (!map->id) 237 return; 238 239 if (do_idr_lock) 240 spin_lock_irqsave(&map_idr_lock, flags); 241 else 242 __acquire(&map_idr_lock); 243 244 idr_remove(&map_idr, map->id); 245 map->id = 0; 246 247 if (do_idr_lock) 248 spin_unlock_irqrestore(&map_idr_lock, flags); 249 else 250 __release(&map_idr_lock); 251 } 252 253 /* called from workqueue */ 254 static void bpf_map_free_deferred(struct work_struct *work) 255 { 256 struct bpf_map *map = container_of(work, struct bpf_map, work); 257 258 bpf_map_uncharge_memlock(map); 259 security_bpf_map_free(map); 260 /* implementation dependent freeing */ 261 map->ops->map_free(map); 262 } 263 264 static void bpf_map_put_uref(struct bpf_map *map) 265 { 266 if (atomic_dec_and_test(&map->usercnt)) { 267 if (map->ops->map_release_uref) 268 map->ops->map_release_uref(map); 269 } 270 } 271 272 /* decrement map refcnt and schedule it for freeing via workqueue 273 * (unrelying map implementation ops->map_free() might sleep) 274 */ 275 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 276 { 277 if (atomic_dec_and_test(&map->refcnt)) { 278 /* bpf_map_free_id() must be called first */ 279 bpf_map_free_id(map, do_idr_lock); 280 btf_put(map->btf); 281 INIT_WORK(&map->work, bpf_map_free_deferred); 282 schedule_work(&map->work); 283 } 284 } 285 286 void bpf_map_put(struct bpf_map *map) 287 { 288 __bpf_map_put(map, true); 289 } 290 EXPORT_SYMBOL_GPL(bpf_map_put); 291 292 void bpf_map_put_with_uref(struct bpf_map *map) 293 { 294 bpf_map_put_uref(map); 295 bpf_map_put(map); 296 } 297 298 static int bpf_map_release(struct inode *inode, struct file *filp) 299 { 300 struct bpf_map *map = filp->private_data; 301 302 if (map->ops->map_release) 303 map->ops->map_release(map, filp); 304 305 bpf_map_put_with_uref(map); 306 return 0; 307 } 308 309 #ifdef CONFIG_PROC_FS 310 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 311 { 312 const struct bpf_map *map = filp->private_data; 313 const struct bpf_array *array; 314 u32 owner_prog_type = 0; 315 u32 owner_jited = 0; 316 317 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 318 array = container_of(map, struct bpf_array, map); 319 owner_prog_type = array->owner_prog_type; 320 owner_jited = array->owner_jited; 321 } 322 323 seq_printf(m, 324 "map_type:\t%u\n" 325 "key_size:\t%u\n" 326 "value_size:\t%u\n" 327 "max_entries:\t%u\n" 328 "map_flags:\t%#x\n" 329 "memlock:\t%llu\n", 330 map->map_type, 331 map->key_size, 332 map->value_size, 333 map->max_entries, 334 map->map_flags, 335 map->pages * 1ULL << PAGE_SHIFT); 336 337 if (owner_prog_type) { 338 seq_printf(m, "owner_prog_type:\t%u\n", 339 owner_prog_type); 340 seq_printf(m, "owner_jited:\t%u\n", 341 owner_jited); 342 } 343 } 344 #endif 345 346 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 347 loff_t *ppos) 348 { 349 /* We need this handler such that alloc_file() enables 350 * f_mode with FMODE_CAN_READ. 351 */ 352 return -EINVAL; 353 } 354 355 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 356 size_t siz, loff_t *ppos) 357 { 358 /* We need this handler such that alloc_file() enables 359 * f_mode with FMODE_CAN_WRITE. 360 */ 361 return -EINVAL; 362 } 363 364 const struct file_operations bpf_map_fops = { 365 #ifdef CONFIG_PROC_FS 366 .show_fdinfo = bpf_map_show_fdinfo, 367 #endif 368 .release = bpf_map_release, 369 .read = bpf_dummy_read, 370 .write = bpf_dummy_write, 371 }; 372 373 int bpf_map_new_fd(struct bpf_map *map, int flags) 374 { 375 int ret; 376 377 ret = security_bpf_map(map, OPEN_FMODE(flags)); 378 if (ret < 0) 379 return ret; 380 381 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 382 flags | O_CLOEXEC); 383 } 384 385 int bpf_get_file_flag(int flags) 386 { 387 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 388 return -EINVAL; 389 if (flags & BPF_F_RDONLY) 390 return O_RDONLY; 391 if (flags & BPF_F_WRONLY) 392 return O_WRONLY; 393 return O_RDWR; 394 } 395 396 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 397 #define CHECK_ATTR(CMD) \ 398 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 399 sizeof(attr->CMD##_LAST_FIELD), 0, \ 400 sizeof(*attr) - \ 401 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 402 sizeof(attr->CMD##_LAST_FIELD)) != NULL 403 404 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes. 405 * Return 0 on success and < 0 on error. 406 */ 407 static int bpf_obj_name_cpy(char *dst, const char *src) 408 { 409 const char *end = src + BPF_OBJ_NAME_LEN; 410 411 memset(dst, 0, BPF_OBJ_NAME_LEN); 412 413 /* Copy all isalnum() and '_' char */ 414 while (src < end && *src) { 415 if (!isalnum(*src) && *src != '_') 416 return -EINVAL; 417 *dst++ = *src++; 418 } 419 420 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */ 421 if (src == end) 422 return -EINVAL; 423 424 return 0; 425 } 426 427 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id 428 /* called via syscall */ 429 static int map_create(union bpf_attr *attr) 430 { 431 int numa_node = bpf_map_attr_numa_node(attr); 432 struct bpf_map *map; 433 int f_flags; 434 int err; 435 436 err = CHECK_ATTR(BPF_MAP_CREATE); 437 if (err) 438 return -EINVAL; 439 440 f_flags = bpf_get_file_flag(attr->map_flags); 441 if (f_flags < 0) 442 return f_flags; 443 444 if (numa_node != NUMA_NO_NODE && 445 ((unsigned int)numa_node >= nr_node_ids || 446 !node_online(numa_node))) 447 return -EINVAL; 448 449 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 450 map = find_and_alloc_map(attr); 451 if (IS_ERR(map)) 452 return PTR_ERR(map); 453 454 err = bpf_obj_name_cpy(map->name, attr->map_name); 455 if (err) 456 goto free_map_nouncharge; 457 458 atomic_set(&map->refcnt, 1); 459 atomic_set(&map->usercnt, 1); 460 461 if (bpf_map_support_seq_show(map) && 462 (attr->btf_key_type_id || attr->btf_value_type_id)) { 463 struct btf *btf; 464 465 if (!attr->btf_key_type_id || !attr->btf_value_type_id) { 466 err = -EINVAL; 467 goto free_map_nouncharge; 468 } 469 470 btf = btf_get_by_fd(attr->btf_fd); 471 if (IS_ERR(btf)) { 472 err = PTR_ERR(btf); 473 goto free_map_nouncharge; 474 } 475 476 err = map->ops->map_check_btf(map, btf, attr->btf_key_type_id, 477 attr->btf_value_type_id); 478 if (err) { 479 btf_put(btf); 480 goto free_map_nouncharge; 481 } 482 483 map->btf = btf; 484 map->btf_key_type_id = attr->btf_key_type_id; 485 map->btf_value_type_id = attr->btf_value_type_id; 486 } 487 488 err = security_bpf_map_alloc(map); 489 if (err) 490 goto free_map_nouncharge; 491 492 err = bpf_map_charge_memlock(map); 493 if (err) 494 goto free_map_sec; 495 496 err = bpf_map_alloc_id(map); 497 if (err) 498 goto free_map; 499 500 err = bpf_map_new_fd(map, f_flags); 501 if (err < 0) { 502 /* failed to allocate fd. 503 * bpf_map_put() is needed because the above 504 * bpf_map_alloc_id() has published the map 505 * to the userspace and the userspace may 506 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 507 */ 508 bpf_map_put(map); 509 return err; 510 } 511 512 return err; 513 514 free_map: 515 bpf_map_uncharge_memlock(map); 516 free_map_sec: 517 security_bpf_map_free(map); 518 free_map_nouncharge: 519 btf_put(map->btf); 520 map->ops->map_free(map); 521 return err; 522 } 523 524 /* if error is returned, fd is released. 525 * On success caller should complete fd access with matching fdput() 526 */ 527 struct bpf_map *__bpf_map_get(struct fd f) 528 { 529 if (!f.file) 530 return ERR_PTR(-EBADF); 531 if (f.file->f_op != &bpf_map_fops) { 532 fdput(f); 533 return ERR_PTR(-EINVAL); 534 } 535 536 return f.file->private_data; 537 } 538 539 /* prog's and map's refcnt limit */ 540 #define BPF_MAX_REFCNT 32768 541 542 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) 543 { 544 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { 545 atomic_dec(&map->refcnt); 546 return ERR_PTR(-EBUSY); 547 } 548 if (uref) 549 atomic_inc(&map->usercnt); 550 return map; 551 } 552 EXPORT_SYMBOL_GPL(bpf_map_inc); 553 554 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 555 { 556 struct fd f = fdget(ufd); 557 struct bpf_map *map; 558 559 map = __bpf_map_get(f); 560 if (IS_ERR(map)) 561 return map; 562 563 map = bpf_map_inc(map, true); 564 fdput(f); 565 566 return map; 567 } 568 569 /* map_idr_lock should have been held */ 570 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, 571 bool uref) 572 { 573 int refold; 574 575 refold = __atomic_add_unless(&map->refcnt, 1, 0); 576 577 if (refold >= BPF_MAX_REFCNT) { 578 __bpf_map_put(map, false); 579 return ERR_PTR(-EBUSY); 580 } 581 582 if (!refold) 583 return ERR_PTR(-ENOENT); 584 585 if (uref) 586 atomic_inc(&map->usercnt); 587 588 return map; 589 } 590 591 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 592 { 593 return -ENOTSUPP; 594 } 595 596 /* last field in 'union bpf_attr' used by this command */ 597 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value 598 599 static int map_lookup_elem(union bpf_attr *attr) 600 { 601 void __user *ukey = u64_to_user_ptr(attr->key); 602 void __user *uvalue = u64_to_user_ptr(attr->value); 603 int ufd = attr->map_fd; 604 struct bpf_map *map; 605 void *key, *value, *ptr; 606 u32 value_size; 607 struct fd f; 608 int err; 609 610 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 611 return -EINVAL; 612 613 f = fdget(ufd); 614 map = __bpf_map_get(f); 615 if (IS_ERR(map)) 616 return PTR_ERR(map); 617 618 if (!(f.file->f_mode & FMODE_CAN_READ)) { 619 err = -EPERM; 620 goto err_put; 621 } 622 623 key = memdup_user(ukey, map->key_size); 624 if (IS_ERR(key)) { 625 err = PTR_ERR(key); 626 goto err_put; 627 } 628 629 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 630 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 631 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 632 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 633 else if (IS_FD_MAP(map)) 634 value_size = sizeof(u32); 635 else 636 value_size = map->value_size; 637 638 err = -ENOMEM; 639 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 640 if (!value) 641 goto free_key; 642 643 if (bpf_map_is_dev_bound(map)) { 644 err = bpf_map_offload_lookup_elem(map, key, value); 645 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 646 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 647 err = bpf_percpu_hash_copy(map, key, value); 648 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 649 err = bpf_percpu_array_copy(map, key, value); 650 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 651 err = bpf_stackmap_copy(map, key, value); 652 } else if (IS_FD_ARRAY(map)) { 653 err = bpf_fd_array_map_lookup_elem(map, key, value); 654 } else if (IS_FD_HASH(map)) { 655 err = bpf_fd_htab_map_lookup_elem(map, key, value); 656 } else { 657 rcu_read_lock(); 658 ptr = map->ops->map_lookup_elem(map, key); 659 if (ptr) 660 memcpy(value, ptr, value_size); 661 rcu_read_unlock(); 662 err = ptr ? 0 : -ENOENT; 663 } 664 665 if (err) 666 goto free_value; 667 668 err = -EFAULT; 669 if (copy_to_user(uvalue, value, value_size) != 0) 670 goto free_value; 671 672 err = 0; 673 674 free_value: 675 kfree(value); 676 free_key: 677 kfree(key); 678 err_put: 679 fdput(f); 680 return err; 681 } 682 683 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 684 685 static int map_update_elem(union bpf_attr *attr) 686 { 687 void __user *ukey = u64_to_user_ptr(attr->key); 688 void __user *uvalue = u64_to_user_ptr(attr->value); 689 int ufd = attr->map_fd; 690 struct bpf_map *map; 691 void *key, *value; 692 u32 value_size; 693 struct fd f; 694 int err; 695 696 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 697 return -EINVAL; 698 699 f = fdget(ufd); 700 map = __bpf_map_get(f); 701 if (IS_ERR(map)) 702 return PTR_ERR(map); 703 704 if (!(f.file->f_mode & FMODE_CAN_WRITE)) { 705 err = -EPERM; 706 goto err_put; 707 } 708 709 key = memdup_user(ukey, map->key_size); 710 if (IS_ERR(key)) { 711 err = PTR_ERR(key); 712 goto err_put; 713 } 714 715 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 716 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 717 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 718 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 719 else 720 value_size = map->value_size; 721 722 err = -ENOMEM; 723 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 724 if (!value) 725 goto free_key; 726 727 err = -EFAULT; 728 if (copy_from_user(value, uvalue, value_size) != 0) 729 goto free_value; 730 731 /* Need to create a kthread, thus must support schedule */ 732 if (bpf_map_is_dev_bound(map)) { 733 err = bpf_map_offload_update_elem(map, key, value, attr->flags); 734 goto out; 735 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) { 736 err = map->ops->map_update_elem(map, key, value, attr->flags); 737 goto out; 738 } 739 740 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from 741 * inside bpf map update or delete otherwise deadlocks are possible 742 */ 743 preempt_disable(); 744 __this_cpu_inc(bpf_prog_active); 745 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 746 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 747 err = bpf_percpu_hash_update(map, key, value, attr->flags); 748 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 749 err = bpf_percpu_array_update(map, key, value, attr->flags); 750 } else if (IS_FD_ARRAY(map)) { 751 rcu_read_lock(); 752 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 753 attr->flags); 754 rcu_read_unlock(); 755 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 756 rcu_read_lock(); 757 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 758 attr->flags); 759 rcu_read_unlock(); 760 } else { 761 rcu_read_lock(); 762 err = map->ops->map_update_elem(map, key, value, attr->flags); 763 rcu_read_unlock(); 764 } 765 __this_cpu_dec(bpf_prog_active); 766 preempt_enable(); 767 out: 768 free_value: 769 kfree(value); 770 free_key: 771 kfree(key); 772 err_put: 773 fdput(f); 774 return err; 775 } 776 777 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 778 779 static int map_delete_elem(union bpf_attr *attr) 780 { 781 void __user *ukey = u64_to_user_ptr(attr->key); 782 int ufd = attr->map_fd; 783 struct bpf_map *map; 784 struct fd f; 785 void *key; 786 int err; 787 788 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 789 return -EINVAL; 790 791 f = fdget(ufd); 792 map = __bpf_map_get(f); 793 if (IS_ERR(map)) 794 return PTR_ERR(map); 795 796 if (!(f.file->f_mode & FMODE_CAN_WRITE)) { 797 err = -EPERM; 798 goto err_put; 799 } 800 801 key = memdup_user(ukey, map->key_size); 802 if (IS_ERR(key)) { 803 err = PTR_ERR(key); 804 goto err_put; 805 } 806 807 if (bpf_map_is_dev_bound(map)) { 808 err = bpf_map_offload_delete_elem(map, key); 809 goto out; 810 } 811 812 preempt_disable(); 813 __this_cpu_inc(bpf_prog_active); 814 rcu_read_lock(); 815 err = map->ops->map_delete_elem(map, key); 816 rcu_read_unlock(); 817 __this_cpu_dec(bpf_prog_active); 818 preempt_enable(); 819 out: 820 kfree(key); 821 err_put: 822 fdput(f); 823 return err; 824 } 825 826 /* last field in 'union bpf_attr' used by this command */ 827 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 828 829 static int map_get_next_key(union bpf_attr *attr) 830 { 831 void __user *ukey = u64_to_user_ptr(attr->key); 832 void __user *unext_key = u64_to_user_ptr(attr->next_key); 833 int ufd = attr->map_fd; 834 struct bpf_map *map; 835 void *key, *next_key; 836 struct fd f; 837 int err; 838 839 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 840 return -EINVAL; 841 842 f = fdget(ufd); 843 map = __bpf_map_get(f); 844 if (IS_ERR(map)) 845 return PTR_ERR(map); 846 847 if (!(f.file->f_mode & FMODE_CAN_READ)) { 848 err = -EPERM; 849 goto err_put; 850 } 851 852 if (ukey) { 853 key = memdup_user(ukey, map->key_size); 854 if (IS_ERR(key)) { 855 err = PTR_ERR(key); 856 goto err_put; 857 } 858 } else { 859 key = NULL; 860 } 861 862 err = -ENOMEM; 863 next_key = kmalloc(map->key_size, GFP_USER); 864 if (!next_key) 865 goto free_key; 866 867 if (bpf_map_is_dev_bound(map)) { 868 err = bpf_map_offload_get_next_key(map, key, next_key); 869 goto out; 870 } 871 872 rcu_read_lock(); 873 err = map->ops->map_get_next_key(map, key, next_key); 874 rcu_read_unlock(); 875 out: 876 if (err) 877 goto free_next_key; 878 879 err = -EFAULT; 880 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 881 goto free_next_key; 882 883 err = 0; 884 885 free_next_key: 886 kfree(next_key); 887 free_key: 888 kfree(key); 889 err_put: 890 fdput(f); 891 return err; 892 } 893 894 static const struct bpf_prog_ops * const bpf_prog_types[] = { 895 #define BPF_PROG_TYPE(_id, _name) \ 896 [_id] = & _name ## _prog_ops, 897 #define BPF_MAP_TYPE(_id, _ops) 898 #include <linux/bpf_types.h> 899 #undef BPF_PROG_TYPE 900 #undef BPF_MAP_TYPE 901 }; 902 903 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 904 { 905 const struct bpf_prog_ops *ops; 906 907 if (type >= ARRAY_SIZE(bpf_prog_types)) 908 return -EINVAL; 909 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 910 ops = bpf_prog_types[type]; 911 if (!ops) 912 return -EINVAL; 913 914 if (!bpf_prog_is_dev_bound(prog->aux)) 915 prog->aux->ops = ops; 916 else 917 prog->aux->ops = &bpf_offload_prog_ops; 918 prog->type = type; 919 return 0; 920 } 921 922 /* drop refcnt on maps used by eBPF program and free auxilary data */ 923 static void free_used_maps(struct bpf_prog_aux *aux) 924 { 925 int i; 926 927 for (i = 0; i < aux->used_map_cnt; i++) 928 bpf_map_put(aux->used_maps[i]); 929 930 kfree(aux->used_maps); 931 } 932 933 int __bpf_prog_charge(struct user_struct *user, u32 pages) 934 { 935 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 936 unsigned long user_bufs; 937 938 if (user) { 939 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 940 if (user_bufs > memlock_limit) { 941 atomic_long_sub(pages, &user->locked_vm); 942 return -EPERM; 943 } 944 } 945 946 return 0; 947 } 948 949 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 950 { 951 if (user) 952 atomic_long_sub(pages, &user->locked_vm); 953 } 954 955 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 956 { 957 struct user_struct *user = get_current_user(); 958 int ret; 959 960 ret = __bpf_prog_charge(user, prog->pages); 961 if (ret) { 962 free_uid(user); 963 return ret; 964 } 965 966 prog->aux->user = user; 967 return 0; 968 } 969 970 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 971 { 972 struct user_struct *user = prog->aux->user; 973 974 __bpf_prog_uncharge(user, prog->pages); 975 free_uid(user); 976 } 977 978 static int bpf_prog_alloc_id(struct bpf_prog *prog) 979 { 980 int id; 981 982 idr_preload(GFP_KERNEL); 983 spin_lock_bh(&prog_idr_lock); 984 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 985 if (id > 0) 986 prog->aux->id = id; 987 spin_unlock_bh(&prog_idr_lock); 988 idr_preload_end(); 989 990 /* id is in [1, INT_MAX) */ 991 if (WARN_ON_ONCE(!id)) 992 return -ENOSPC; 993 994 return id > 0 ? 0 : id; 995 } 996 997 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 998 { 999 /* cBPF to eBPF migrations are currently not in the idr store. 1000 * Offloaded programs are removed from the store when their device 1001 * disappears - even if someone grabs an fd to them they are unusable, 1002 * simply waiting for refcnt to drop to be freed. 1003 */ 1004 if (!prog->aux->id) 1005 return; 1006 1007 if (do_idr_lock) 1008 spin_lock_bh(&prog_idr_lock); 1009 else 1010 __acquire(&prog_idr_lock); 1011 1012 idr_remove(&prog_idr, prog->aux->id); 1013 prog->aux->id = 0; 1014 1015 if (do_idr_lock) 1016 spin_unlock_bh(&prog_idr_lock); 1017 else 1018 __release(&prog_idr_lock); 1019 } 1020 1021 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1022 { 1023 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1024 1025 free_used_maps(aux); 1026 bpf_prog_uncharge_memlock(aux->prog); 1027 security_bpf_prog_free(aux); 1028 bpf_prog_free(aux->prog); 1029 } 1030 1031 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1032 { 1033 if (atomic_dec_and_test(&prog->aux->refcnt)) { 1034 int i; 1035 1036 /* bpf_prog_free_id() must be called first */ 1037 bpf_prog_free_id(prog, do_idr_lock); 1038 1039 for (i = 0; i < prog->aux->func_cnt; i++) 1040 bpf_prog_kallsyms_del(prog->aux->func[i]); 1041 bpf_prog_kallsyms_del(prog); 1042 1043 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1044 } 1045 } 1046 1047 void bpf_prog_put(struct bpf_prog *prog) 1048 { 1049 __bpf_prog_put(prog, true); 1050 } 1051 EXPORT_SYMBOL_GPL(bpf_prog_put); 1052 1053 static int bpf_prog_release(struct inode *inode, struct file *filp) 1054 { 1055 struct bpf_prog *prog = filp->private_data; 1056 1057 bpf_prog_put(prog); 1058 return 0; 1059 } 1060 1061 #ifdef CONFIG_PROC_FS 1062 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1063 { 1064 const struct bpf_prog *prog = filp->private_data; 1065 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1066 1067 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1068 seq_printf(m, 1069 "prog_type:\t%u\n" 1070 "prog_jited:\t%u\n" 1071 "prog_tag:\t%s\n" 1072 "memlock:\t%llu\n", 1073 prog->type, 1074 prog->jited, 1075 prog_tag, 1076 prog->pages * 1ULL << PAGE_SHIFT); 1077 } 1078 #endif 1079 1080 const struct file_operations bpf_prog_fops = { 1081 #ifdef CONFIG_PROC_FS 1082 .show_fdinfo = bpf_prog_show_fdinfo, 1083 #endif 1084 .release = bpf_prog_release, 1085 .read = bpf_dummy_read, 1086 .write = bpf_dummy_write, 1087 }; 1088 1089 int bpf_prog_new_fd(struct bpf_prog *prog) 1090 { 1091 int ret; 1092 1093 ret = security_bpf_prog(prog); 1094 if (ret < 0) 1095 return ret; 1096 1097 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1098 O_RDWR | O_CLOEXEC); 1099 } 1100 1101 static struct bpf_prog *____bpf_prog_get(struct fd f) 1102 { 1103 if (!f.file) 1104 return ERR_PTR(-EBADF); 1105 if (f.file->f_op != &bpf_prog_fops) { 1106 fdput(f); 1107 return ERR_PTR(-EINVAL); 1108 } 1109 1110 return f.file->private_data; 1111 } 1112 1113 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) 1114 { 1115 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) { 1116 atomic_sub(i, &prog->aux->refcnt); 1117 return ERR_PTR(-EBUSY); 1118 } 1119 return prog; 1120 } 1121 EXPORT_SYMBOL_GPL(bpf_prog_add); 1122 1123 void bpf_prog_sub(struct bpf_prog *prog, int i) 1124 { 1125 /* Only to be used for undoing previous bpf_prog_add() in some 1126 * error path. We still know that another entity in our call 1127 * path holds a reference to the program, thus atomic_sub() can 1128 * be safely used in such cases! 1129 */ 1130 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0); 1131 } 1132 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1133 1134 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) 1135 { 1136 return bpf_prog_add(prog, 1); 1137 } 1138 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1139 1140 /* prog_idr_lock should have been held */ 1141 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1142 { 1143 int refold; 1144 1145 refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0); 1146 1147 if (refold >= BPF_MAX_REFCNT) { 1148 __bpf_prog_put(prog, false); 1149 return ERR_PTR(-EBUSY); 1150 } 1151 1152 if (!refold) 1153 return ERR_PTR(-ENOENT); 1154 1155 return prog; 1156 } 1157 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1158 1159 bool bpf_prog_get_ok(struct bpf_prog *prog, 1160 enum bpf_prog_type *attach_type, bool attach_drv) 1161 { 1162 /* not an attachment, just a refcount inc, always allow */ 1163 if (!attach_type) 1164 return true; 1165 1166 if (prog->type != *attach_type) 1167 return false; 1168 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1169 return false; 1170 1171 return true; 1172 } 1173 1174 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1175 bool attach_drv) 1176 { 1177 struct fd f = fdget(ufd); 1178 struct bpf_prog *prog; 1179 1180 prog = ____bpf_prog_get(f); 1181 if (IS_ERR(prog)) 1182 return prog; 1183 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1184 prog = ERR_PTR(-EINVAL); 1185 goto out; 1186 } 1187 1188 prog = bpf_prog_inc(prog); 1189 out: 1190 fdput(f); 1191 return prog; 1192 } 1193 1194 struct bpf_prog *bpf_prog_get(u32 ufd) 1195 { 1196 return __bpf_prog_get(ufd, NULL, false); 1197 } 1198 1199 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1200 bool attach_drv) 1201 { 1202 return __bpf_prog_get(ufd, &type, attach_drv); 1203 } 1204 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1205 1206 /* Initially all BPF programs could be loaded w/o specifying 1207 * expected_attach_type. Later for some of them specifying expected_attach_type 1208 * at load time became required so that program could be validated properly. 1209 * Programs of types that are allowed to be loaded both w/ and w/o (for 1210 * backward compatibility) expected_attach_type, should have the default attach 1211 * type assigned to expected_attach_type for the latter case, so that it can be 1212 * validated later at attach time. 1213 * 1214 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1215 * prog type requires it but has some attach types that have to be backward 1216 * compatible. 1217 */ 1218 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1219 { 1220 switch (attr->prog_type) { 1221 case BPF_PROG_TYPE_CGROUP_SOCK: 1222 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1223 * exist so checking for non-zero is the way to go here. 1224 */ 1225 if (!attr->expected_attach_type) 1226 attr->expected_attach_type = 1227 BPF_CGROUP_INET_SOCK_CREATE; 1228 break; 1229 } 1230 } 1231 1232 static int 1233 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type, 1234 enum bpf_attach_type expected_attach_type) 1235 { 1236 switch (prog_type) { 1237 case BPF_PROG_TYPE_CGROUP_SOCK: 1238 switch (expected_attach_type) { 1239 case BPF_CGROUP_INET_SOCK_CREATE: 1240 case BPF_CGROUP_INET4_POST_BIND: 1241 case BPF_CGROUP_INET6_POST_BIND: 1242 return 0; 1243 default: 1244 return -EINVAL; 1245 } 1246 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1247 switch (expected_attach_type) { 1248 case BPF_CGROUP_INET4_BIND: 1249 case BPF_CGROUP_INET6_BIND: 1250 case BPF_CGROUP_INET4_CONNECT: 1251 case BPF_CGROUP_INET6_CONNECT: 1252 return 0; 1253 default: 1254 return -EINVAL; 1255 } 1256 default: 1257 return 0; 1258 } 1259 } 1260 1261 /* last field in 'union bpf_attr' used by this command */ 1262 #define BPF_PROG_LOAD_LAST_FIELD expected_attach_type 1263 1264 static int bpf_prog_load(union bpf_attr *attr) 1265 { 1266 enum bpf_prog_type type = attr->prog_type; 1267 struct bpf_prog *prog; 1268 int err; 1269 char license[128]; 1270 bool is_gpl; 1271 1272 if (CHECK_ATTR(BPF_PROG_LOAD)) 1273 return -EINVAL; 1274 1275 if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT) 1276 return -EINVAL; 1277 1278 /* copy eBPF program license from user space */ 1279 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 1280 sizeof(license) - 1) < 0) 1281 return -EFAULT; 1282 license[sizeof(license) - 1] = 0; 1283 1284 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 1285 is_gpl = license_is_gpl_compatible(license); 1286 1287 if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS) 1288 return -E2BIG; 1289 1290 if (type == BPF_PROG_TYPE_KPROBE && 1291 attr->kern_version != LINUX_VERSION_CODE) 1292 return -EINVAL; 1293 1294 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 1295 type != BPF_PROG_TYPE_CGROUP_SKB && 1296 !capable(CAP_SYS_ADMIN)) 1297 return -EPERM; 1298 1299 bpf_prog_load_fixup_attach_type(attr); 1300 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type)) 1301 return -EINVAL; 1302 1303 /* plain bpf_prog allocation */ 1304 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 1305 if (!prog) 1306 return -ENOMEM; 1307 1308 prog->expected_attach_type = attr->expected_attach_type; 1309 1310 prog->aux->offload_requested = !!attr->prog_ifindex; 1311 1312 err = security_bpf_prog_alloc(prog->aux); 1313 if (err) 1314 goto free_prog_nouncharge; 1315 1316 err = bpf_prog_charge_memlock(prog); 1317 if (err) 1318 goto free_prog_sec; 1319 1320 prog->len = attr->insn_cnt; 1321 1322 err = -EFAULT; 1323 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 1324 bpf_prog_insn_size(prog)) != 0) 1325 goto free_prog; 1326 1327 prog->orig_prog = NULL; 1328 prog->jited = 0; 1329 1330 atomic_set(&prog->aux->refcnt, 1); 1331 prog->gpl_compatible = is_gpl ? 1 : 0; 1332 1333 if (bpf_prog_is_dev_bound(prog->aux)) { 1334 err = bpf_prog_offload_init(prog, attr); 1335 if (err) 1336 goto free_prog; 1337 } 1338 1339 /* find program type: socket_filter vs tracing_filter */ 1340 err = find_prog_type(type, prog); 1341 if (err < 0) 1342 goto free_prog; 1343 1344 prog->aux->load_time = ktime_get_boot_ns(); 1345 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 1346 if (err) 1347 goto free_prog; 1348 1349 /* run eBPF verifier */ 1350 err = bpf_check(&prog, attr); 1351 if (err < 0) 1352 goto free_used_maps; 1353 1354 /* eBPF program is ready to be JITed */ 1355 if (!prog->bpf_func) 1356 prog = bpf_prog_select_runtime(prog, &err); 1357 if (err < 0) 1358 goto free_used_maps; 1359 1360 err = bpf_prog_alloc_id(prog); 1361 if (err) 1362 goto free_used_maps; 1363 1364 err = bpf_prog_new_fd(prog); 1365 if (err < 0) { 1366 /* failed to allocate fd. 1367 * bpf_prog_put() is needed because the above 1368 * bpf_prog_alloc_id() has published the prog 1369 * to the userspace and the userspace may 1370 * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID. 1371 */ 1372 bpf_prog_put(prog); 1373 return err; 1374 } 1375 1376 bpf_prog_kallsyms_add(prog); 1377 return err; 1378 1379 free_used_maps: 1380 free_used_maps(prog->aux); 1381 free_prog: 1382 bpf_prog_uncharge_memlock(prog); 1383 free_prog_sec: 1384 security_bpf_prog_free(prog->aux); 1385 free_prog_nouncharge: 1386 bpf_prog_free(prog); 1387 return err; 1388 } 1389 1390 #define BPF_OBJ_LAST_FIELD file_flags 1391 1392 static int bpf_obj_pin(const union bpf_attr *attr) 1393 { 1394 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 1395 return -EINVAL; 1396 1397 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 1398 } 1399 1400 static int bpf_obj_get(const union bpf_attr *attr) 1401 { 1402 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 1403 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 1404 return -EINVAL; 1405 1406 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 1407 attr->file_flags); 1408 } 1409 1410 struct bpf_raw_tracepoint { 1411 struct bpf_raw_event_map *btp; 1412 struct bpf_prog *prog; 1413 }; 1414 1415 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) 1416 { 1417 struct bpf_raw_tracepoint *raw_tp = filp->private_data; 1418 1419 if (raw_tp->prog) { 1420 bpf_probe_unregister(raw_tp->btp, raw_tp->prog); 1421 bpf_prog_put(raw_tp->prog); 1422 } 1423 kfree(raw_tp); 1424 return 0; 1425 } 1426 1427 static const struct file_operations bpf_raw_tp_fops = { 1428 .release = bpf_raw_tracepoint_release, 1429 .read = bpf_dummy_read, 1430 .write = bpf_dummy_write, 1431 }; 1432 1433 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 1434 1435 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 1436 { 1437 struct bpf_raw_tracepoint *raw_tp; 1438 struct bpf_raw_event_map *btp; 1439 struct bpf_prog *prog; 1440 char tp_name[128]; 1441 int tp_fd, err; 1442 1443 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name), 1444 sizeof(tp_name) - 1) < 0) 1445 return -EFAULT; 1446 tp_name[sizeof(tp_name) - 1] = 0; 1447 1448 btp = bpf_find_raw_tracepoint(tp_name); 1449 if (!btp) 1450 return -ENOENT; 1451 1452 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 1453 if (!raw_tp) 1454 return -ENOMEM; 1455 raw_tp->btp = btp; 1456 1457 prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd, 1458 BPF_PROG_TYPE_RAW_TRACEPOINT); 1459 if (IS_ERR(prog)) { 1460 err = PTR_ERR(prog); 1461 goto out_free_tp; 1462 } 1463 1464 err = bpf_probe_register(raw_tp->btp, prog); 1465 if (err) 1466 goto out_put_prog; 1467 1468 raw_tp->prog = prog; 1469 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp, 1470 O_CLOEXEC); 1471 if (tp_fd < 0) { 1472 bpf_probe_unregister(raw_tp->btp, prog); 1473 err = tp_fd; 1474 goto out_put_prog; 1475 } 1476 return tp_fd; 1477 1478 out_put_prog: 1479 bpf_prog_put(prog); 1480 out_free_tp: 1481 kfree(raw_tp); 1482 return err; 1483 } 1484 1485 #ifdef CONFIG_CGROUP_BPF 1486 1487 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 1488 enum bpf_attach_type attach_type) 1489 { 1490 switch (prog->type) { 1491 case BPF_PROG_TYPE_CGROUP_SOCK: 1492 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1493 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 1494 default: 1495 return 0; 1496 } 1497 } 1498 1499 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags 1500 1501 static int sockmap_get_from_fd(const union bpf_attr *attr, 1502 int type, bool attach) 1503 { 1504 struct bpf_prog *prog = NULL; 1505 int ufd = attr->target_fd; 1506 struct bpf_map *map; 1507 struct fd f; 1508 int err; 1509 1510 f = fdget(ufd); 1511 map = __bpf_map_get(f); 1512 if (IS_ERR(map)) 1513 return PTR_ERR(map); 1514 1515 if (attach) { 1516 prog = bpf_prog_get_type(attr->attach_bpf_fd, type); 1517 if (IS_ERR(prog)) { 1518 fdput(f); 1519 return PTR_ERR(prog); 1520 } 1521 } 1522 1523 err = sock_map_prog(map, prog, attr->attach_type); 1524 if (err) { 1525 fdput(f); 1526 if (prog) 1527 bpf_prog_put(prog); 1528 return err; 1529 } 1530 1531 fdput(f); 1532 return 0; 1533 } 1534 1535 #define BPF_F_ATTACH_MASK \ 1536 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) 1537 1538 static int bpf_prog_attach(const union bpf_attr *attr) 1539 { 1540 enum bpf_prog_type ptype; 1541 struct bpf_prog *prog; 1542 struct cgroup *cgrp; 1543 int ret; 1544 1545 if (!capable(CAP_NET_ADMIN)) 1546 return -EPERM; 1547 1548 if (CHECK_ATTR(BPF_PROG_ATTACH)) 1549 return -EINVAL; 1550 1551 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 1552 return -EINVAL; 1553 1554 switch (attr->attach_type) { 1555 case BPF_CGROUP_INET_INGRESS: 1556 case BPF_CGROUP_INET_EGRESS: 1557 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1558 break; 1559 case BPF_CGROUP_INET_SOCK_CREATE: 1560 case BPF_CGROUP_INET4_POST_BIND: 1561 case BPF_CGROUP_INET6_POST_BIND: 1562 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1563 break; 1564 case BPF_CGROUP_INET4_BIND: 1565 case BPF_CGROUP_INET6_BIND: 1566 case BPF_CGROUP_INET4_CONNECT: 1567 case BPF_CGROUP_INET6_CONNECT: 1568 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1569 break; 1570 case BPF_CGROUP_SOCK_OPS: 1571 ptype = BPF_PROG_TYPE_SOCK_OPS; 1572 break; 1573 case BPF_CGROUP_DEVICE: 1574 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1575 break; 1576 case BPF_SK_MSG_VERDICT: 1577 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, true); 1578 case BPF_SK_SKB_STREAM_PARSER: 1579 case BPF_SK_SKB_STREAM_VERDICT: 1580 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, true); 1581 default: 1582 return -EINVAL; 1583 } 1584 1585 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1586 if (IS_ERR(prog)) 1587 return PTR_ERR(prog); 1588 1589 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 1590 bpf_prog_put(prog); 1591 return -EINVAL; 1592 } 1593 1594 cgrp = cgroup_get_from_fd(attr->target_fd); 1595 if (IS_ERR(cgrp)) { 1596 bpf_prog_put(prog); 1597 return PTR_ERR(cgrp); 1598 } 1599 1600 ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type, 1601 attr->attach_flags); 1602 if (ret) 1603 bpf_prog_put(prog); 1604 cgroup_put(cgrp); 1605 1606 return ret; 1607 } 1608 1609 #define BPF_PROG_DETACH_LAST_FIELD attach_type 1610 1611 static int bpf_prog_detach(const union bpf_attr *attr) 1612 { 1613 enum bpf_prog_type ptype; 1614 struct bpf_prog *prog; 1615 struct cgroup *cgrp; 1616 int ret; 1617 1618 if (!capable(CAP_NET_ADMIN)) 1619 return -EPERM; 1620 1621 if (CHECK_ATTR(BPF_PROG_DETACH)) 1622 return -EINVAL; 1623 1624 switch (attr->attach_type) { 1625 case BPF_CGROUP_INET_INGRESS: 1626 case BPF_CGROUP_INET_EGRESS: 1627 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1628 break; 1629 case BPF_CGROUP_INET_SOCK_CREATE: 1630 case BPF_CGROUP_INET4_POST_BIND: 1631 case BPF_CGROUP_INET6_POST_BIND: 1632 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1633 break; 1634 case BPF_CGROUP_INET4_BIND: 1635 case BPF_CGROUP_INET6_BIND: 1636 case BPF_CGROUP_INET4_CONNECT: 1637 case BPF_CGROUP_INET6_CONNECT: 1638 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1639 break; 1640 case BPF_CGROUP_SOCK_OPS: 1641 ptype = BPF_PROG_TYPE_SOCK_OPS; 1642 break; 1643 case BPF_CGROUP_DEVICE: 1644 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1645 break; 1646 case BPF_SK_MSG_VERDICT: 1647 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, false); 1648 case BPF_SK_SKB_STREAM_PARSER: 1649 case BPF_SK_SKB_STREAM_VERDICT: 1650 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, false); 1651 default: 1652 return -EINVAL; 1653 } 1654 1655 cgrp = cgroup_get_from_fd(attr->target_fd); 1656 if (IS_ERR(cgrp)) 1657 return PTR_ERR(cgrp); 1658 1659 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1660 if (IS_ERR(prog)) 1661 prog = NULL; 1662 1663 ret = cgroup_bpf_detach(cgrp, prog, attr->attach_type, 0); 1664 if (prog) 1665 bpf_prog_put(prog); 1666 cgroup_put(cgrp); 1667 return ret; 1668 } 1669 1670 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 1671 1672 static int bpf_prog_query(const union bpf_attr *attr, 1673 union bpf_attr __user *uattr) 1674 { 1675 struct cgroup *cgrp; 1676 int ret; 1677 1678 if (!capable(CAP_NET_ADMIN)) 1679 return -EPERM; 1680 if (CHECK_ATTR(BPF_PROG_QUERY)) 1681 return -EINVAL; 1682 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 1683 return -EINVAL; 1684 1685 switch (attr->query.attach_type) { 1686 case BPF_CGROUP_INET_INGRESS: 1687 case BPF_CGROUP_INET_EGRESS: 1688 case BPF_CGROUP_INET_SOCK_CREATE: 1689 case BPF_CGROUP_INET4_BIND: 1690 case BPF_CGROUP_INET6_BIND: 1691 case BPF_CGROUP_INET4_POST_BIND: 1692 case BPF_CGROUP_INET6_POST_BIND: 1693 case BPF_CGROUP_INET4_CONNECT: 1694 case BPF_CGROUP_INET6_CONNECT: 1695 case BPF_CGROUP_SOCK_OPS: 1696 case BPF_CGROUP_DEVICE: 1697 break; 1698 default: 1699 return -EINVAL; 1700 } 1701 cgrp = cgroup_get_from_fd(attr->query.target_fd); 1702 if (IS_ERR(cgrp)) 1703 return PTR_ERR(cgrp); 1704 ret = cgroup_bpf_query(cgrp, attr, uattr); 1705 cgroup_put(cgrp); 1706 return ret; 1707 } 1708 #endif /* CONFIG_CGROUP_BPF */ 1709 1710 #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration 1711 1712 static int bpf_prog_test_run(const union bpf_attr *attr, 1713 union bpf_attr __user *uattr) 1714 { 1715 struct bpf_prog *prog; 1716 int ret = -ENOTSUPP; 1717 1718 if (!capable(CAP_SYS_ADMIN)) 1719 return -EPERM; 1720 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 1721 return -EINVAL; 1722 1723 prog = bpf_prog_get(attr->test.prog_fd); 1724 if (IS_ERR(prog)) 1725 return PTR_ERR(prog); 1726 1727 if (prog->aux->ops->test_run) 1728 ret = prog->aux->ops->test_run(prog, attr, uattr); 1729 1730 bpf_prog_put(prog); 1731 return ret; 1732 } 1733 1734 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 1735 1736 static int bpf_obj_get_next_id(const union bpf_attr *attr, 1737 union bpf_attr __user *uattr, 1738 struct idr *idr, 1739 spinlock_t *lock) 1740 { 1741 u32 next_id = attr->start_id; 1742 int err = 0; 1743 1744 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 1745 return -EINVAL; 1746 1747 if (!capable(CAP_SYS_ADMIN)) 1748 return -EPERM; 1749 1750 next_id++; 1751 spin_lock_bh(lock); 1752 if (!idr_get_next(idr, &next_id)) 1753 err = -ENOENT; 1754 spin_unlock_bh(lock); 1755 1756 if (!err) 1757 err = put_user(next_id, &uattr->next_id); 1758 1759 return err; 1760 } 1761 1762 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 1763 1764 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 1765 { 1766 struct bpf_prog *prog; 1767 u32 id = attr->prog_id; 1768 int fd; 1769 1770 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 1771 return -EINVAL; 1772 1773 if (!capable(CAP_SYS_ADMIN)) 1774 return -EPERM; 1775 1776 spin_lock_bh(&prog_idr_lock); 1777 prog = idr_find(&prog_idr, id); 1778 if (prog) 1779 prog = bpf_prog_inc_not_zero(prog); 1780 else 1781 prog = ERR_PTR(-ENOENT); 1782 spin_unlock_bh(&prog_idr_lock); 1783 1784 if (IS_ERR(prog)) 1785 return PTR_ERR(prog); 1786 1787 fd = bpf_prog_new_fd(prog); 1788 if (fd < 0) 1789 bpf_prog_put(prog); 1790 1791 return fd; 1792 } 1793 1794 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 1795 1796 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 1797 { 1798 struct bpf_map *map; 1799 u32 id = attr->map_id; 1800 int f_flags; 1801 int fd; 1802 1803 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 1804 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 1805 return -EINVAL; 1806 1807 if (!capable(CAP_SYS_ADMIN)) 1808 return -EPERM; 1809 1810 f_flags = bpf_get_file_flag(attr->open_flags); 1811 if (f_flags < 0) 1812 return f_flags; 1813 1814 spin_lock_bh(&map_idr_lock); 1815 map = idr_find(&map_idr, id); 1816 if (map) 1817 map = bpf_map_inc_not_zero(map, true); 1818 else 1819 map = ERR_PTR(-ENOENT); 1820 spin_unlock_bh(&map_idr_lock); 1821 1822 if (IS_ERR(map)) 1823 return PTR_ERR(map); 1824 1825 fd = bpf_map_new_fd(map, f_flags); 1826 if (fd < 0) 1827 bpf_map_put(map); 1828 1829 return fd; 1830 } 1831 1832 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 1833 unsigned long addr) 1834 { 1835 int i; 1836 1837 for (i = 0; i < prog->aux->used_map_cnt; i++) 1838 if (prog->aux->used_maps[i] == (void *)addr) 1839 return prog->aux->used_maps[i]; 1840 return NULL; 1841 } 1842 1843 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 1844 { 1845 const struct bpf_map *map; 1846 struct bpf_insn *insns; 1847 u64 imm; 1848 int i; 1849 1850 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 1851 GFP_USER); 1852 if (!insns) 1853 return insns; 1854 1855 for (i = 0; i < prog->len; i++) { 1856 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 1857 insns[i].code = BPF_JMP | BPF_CALL; 1858 insns[i].imm = BPF_FUNC_tail_call; 1859 /* fall-through */ 1860 } 1861 if (insns[i].code == (BPF_JMP | BPF_CALL) || 1862 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 1863 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 1864 insns[i].code = BPF_JMP | BPF_CALL; 1865 if (!bpf_dump_raw_ok()) 1866 insns[i].imm = 0; 1867 continue; 1868 } 1869 1870 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 1871 continue; 1872 1873 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 1874 map = bpf_map_from_imm(prog, imm); 1875 if (map) { 1876 insns[i].src_reg = BPF_PSEUDO_MAP_FD; 1877 insns[i].imm = map->id; 1878 insns[i + 1].imm = 0; 1879 continue; 1880 } 1881 1882 if (!bpf_dump_raw_ok() && 1883 imm == (unsigned long)prog->aux) { 1884 insns[i].imm = 0; 1885 insns[i + 1].imm = 0; 1886 continue; 1887 } 1888 } 1889 1890 return insns; 1891 } 1892 1893 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 1894 const union bpf_attr *attr, 1895 union bpf_attr __user *uattr) 1896 { 1897 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 1898 struct bpf_prog_info info = {}; 1899 u32 info_len = attr->info.info_len; 1900 char __user *uinsns; 1901 u32 ulen; 1902 int err; 1903 1904 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 1905 if (err) 1906 return err; 1907 info_len = min_t(u32, sizeof(info), info_len); 1908 1909 if (copy_from_user(&info, uinfo, info_len)) 1910 return -EFAULT; 1911 1912 info.type = prog->type; 1913 info.id = prog->aux->id; 1914 info.load_time = prog->aux->load_time; 1915 info.created_by_uid = from_kuid_munged(current_user_ns(), 1916 prog->aux->user->uid); 1917 info.gpl_compatible = prog->gpl_compatible; 1918 1919 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 1920 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 1921 1922 ulen = info.nr_map_ids; 1923 info.nr_map_ids = prog->aux->used_map_cnt; 1924 ulen = min_t(u32, info.nr_map_ids, ulen); 1925 if (ulen) { 1926 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 1927 u32 i; 1928 1929 for (i = 0; i < ulen; i++) 1930 if (put_user(prog->aux->used_maps[i]->id, 1931 &user_map_ids[i])) 1932 return -EFAULT; 1933 } 1934 1935 if (!capable(CAP_SYS_ADMIN)) { 1936 info.jited_prog_len = 0; 1937 info.xlated_prog_len = 0; 1938 info.nr_jited_ksyms = 0; 1939 goto done; 1940 } 1941 1942 ulen = info.xlated_prog_len; 1943 info.xlated_prog_len = bpf_prog_insn_size(prog); 1944 if (info.xlated_prog_len && ulen) { 1945 struct bpf_insn *insns_sanitized; 1946 bool fault; 1947 1948 if (prog->blinded && !bpf_dump_raw_ok()) { 1949 info.xlated_prog_insns = 0; 1950 goto done; 1951 } 1952 insns_sanitized = bpf_insn_prepare_dump(prog); 1953 if (!insns_sanitized) 1954 return -ENOMEM; 1955 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 1956 ulen = min_t(u32, info.xlated_prog_len, ulen); 1957 fault = copy_to_user(uinsns, insns_sanitized, ulen); 1958 kfree(insns_sanitized); 1959 if (fault) 1960 return -EFAULT; 1961 } 1962 1963 if (bpf_prog_is_dev_bound(prog->aux)) { 1964 err = bpf_prog_offload_info_fill(&info, prog); 1965 if (err) 1966 return err; 1967 goto done; 1968 } 1969 1970 /* NOTE: the following code is supposed to be skipped for offload. 1971 * bpf_prog_offload_info_fill() is the place to fill similar fields 1972 * for offload. 1973 */ 1974 ulen = info.jited_prog_len; 1975 if (prog->aux->func_cnt) { 1976 u32 i; 1977 1978 info.jited_prog_len = 0; 1979 for (i = 0; i < prog->aux->func_cnt; i++) 1980 info.jited_prog_len += prog->aux->func[i]->jited_len; 1981 } else { 1982 info.jited_prog_len = prog->jited_len; 1983 } 1984 1985 if (info.jited_prog_len && ulen) { 1986 if (bpf_dump_raw_ok()) { 1987 uinsns = u64_to_user_ptr(info.jited_prog_insns); 1988 ulen = min_t(u32, info.jited_prog_len, ulen); 1989 1990 /* for multi-function programs, copy the JITed 1991 * instructions for all the functions 1992 */ 1993 if (prog->aux->func_cnt) { 1994 u32 len, free, i; 1995 u8 *img; 1996 1997 free = ulen; 1998 for (i = 0; i < prog->aux->func_cnt; i++) { 1999 len = prog->aux->func[i]->jited_len; 2000 len = min_t(u32, len, free); 2001 img = (u8 *) prog->aux->func[i]->bpf_func; 2002 if (copy_to_user(uinsns, img, len)) 2003 return -EFAULT; 2004 uinsns += len; 2005 free -= len; 2006 if (!free) 2007 break; 2008 } 2009 } else { 2010 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 2011 return -EFAULT; 2012 } 2013 } else { 2014 info.jited_prog_insns = 0; 2015 } 2016 } 2017 2018 ulen = info.nr_jited_ksyms; 2019 info.nr_jited_ksyms = prog->aux->func_cnt; 2020 if (info.nr_jited_ksyms && ulen) { 2021 if (bpf_dump_raw_ok()) { 2022 u64 __user *user_ksyms; 2023 ulong ksym_addr; 2024 u32 i; 2025 2026 /* copy the address of the kernel symbol 2027 * corresponding to each function 2028 */ 2029 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 2030 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 2031 for (i = 0; i < ulen; i++) { 2032 ksym_addr = (ulong) prog->aux->func[i]->bpf_func; 2033 ksym_addr &= PAGE_MASK; 2034 if (put_user((u64) ksym_addr, &user_ksyms[i])) 2035 return -EFAULT; 2036 } 2037 } else { 2038 info.jited_ksyms = 0; 2039 } 2040 } 2041 2042 ulen = info.nr_jited_func_lens; 2043 info.nr_jited_func_lens = prog->aux->func_cnt; 2044 if (info.nr_jited_func_lens && ulen) { 2045 if (bpf_dump_raw_ok()) { 2046 u32 __user *user_lens; 2047 u32 func_len, i; 2048 2049 /* copy the JITed image lengths for each function */ 2050 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 2051 user_lens = u64_to_user_ptr(info.jited_func_lens); 2052 for (i = 0; i < ulen; i++) { 2053 func_len = prog->aux->func[i]->jited_len; 2054 if (put_user(func_len, &user_lens[i])) 2055 return -EFAULT; 2056 } 2057 } else { 2058 info.jited_func_lens = 0; 2059 } 2060 } 2061 2062 done: 2063 if (copy_to_user(uinfo, &info, info_len) || 2064 put_user(info_len, &uattr->info.info_len)) 2065 return -EFAULT; 2066 2067 return 0; 2068 } 2069 2070 static int bpf_map_get_info_by_fd(struct bpf_map *map, 2071 const union bpf_attr *attr, 2072 union bpf_attr __user *uattr) 2073 { 2074 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2075 struct bpf_map_info info = {}; 2076 u32 info_len = attr->info.info_len; 2077 int err; 2078 2079 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2080 if (err) 2081 return err; 2082 info_len = min_t(u32, sizeof(info), info_len); 2083 2084 info.type = map->map_type; 2085 info.id = map->id; 2086 info.key_size = map->key_size; 2087 info.value_size = map->value_size; 2088 info.max_entries = map->max_entries; 2089 info.map_flags = map->map_flags; 2090 memcpy(info.name, map->name, sizeof(map->name)); 2091 2092 if (map->btf) { 2093 info.btf_id = btf_id(map->btf); 2094 info.btf_key_type_id = map->btf_key_type_id; 2095 info.btf_value_type_id = map->btf_value_type_id; 2096 } 2097 2098 if (bpf_map_is_dev_bound(map)) { 2099 err = bpf_map_offload_info_fill(&info, map); 2100 if (err) 2101 return err; 2102 } 2103 2104 if (copy_to_user(uinfo, &info, info_len) || 2105 put_user(info_len, &uattr->info.info_len)) 2106 return -EFAULT; 2107 2108 return 0; 2109 } 2110 2111 static int bpf_btf_get_info_by_fd(struct btf *btf, 2112 const union bpf_attr *attr, 2113 union bpf_attr __user *uattr) 2114 { 2115 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2116 u32 info_len = attr->info.info_len; 2117 int err; 2118 2119 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 2120 if (err) 2121 return err; 2122 2123 return btf_get_info_by_fd(btf, attr, uattr); 2124 } 2125 2126 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 2127 2128 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 2129 union bpf_attr __user *uattr) 2130 { 2131 int ufd = attr->info.bpf_fd; 2132 struct fd f; 2133 int err; 2134 2135 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 2136 return -EINVAL; 2137 2138 f = fdget(ufd); 2139 if (!f.file) 2140 return -EBADFD; 2141 2142 if (f.file->f_op == &bpf_prog_fops) 2143 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 2144 uattr); 2145 else if (f.file->f_op == &bpf_map_fops) 2146 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 2147 uattr); 2148 else if (f.file->f_op == &btf_fops) 2149 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 2150 else 2151 err = -EINVAL; 2152 2153 fdput(f); 2154 return err; 2155 } 2156 2157 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 2158 2159 static int bpf_btf_load(const union bpf_attr *attr) 2160 { 2161 if (CHECK_ATTR(BPF_BTF_LOAD)) 2162 return -EINVAL; 2163 2164 if (!capable(CAP_SYS_ADMIN)) 2165 return -EPERM; 2166 2167 return btf_new_fd(attr); 2168 } 2169 2170 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 2171 2172 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 2173 { 2174 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 2175 return -EINVAL; 2176 2177 if (!capable(CAP_SYS_ADMIN)) 2178 return -EPERM; 2179 2180 return btf_get_fd_by_id(attr->btf_id); 2181 } 2182 2183 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 2184 union bpf_attr __user *uattr, 2185 u32 prog_id, u32 fd_type, 2186 const char *buf, u64 probe_offset, 2187 u64 probe_addr) 2188 { 2189 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 2190 u32 len = buf ? strlen(buf) : 0, input_len; 2191 int err = 0; 2192 2193 if (put_user(len, &uattr->task_fd_query.buf_len)) 2194 return -EFAULT; 2195 input_len = attr->task_fd_query.buf_len; 2196 if (input_len && ubuf) { 2197 if (!len) { 2198 /* nothing to copy, just make ubuf NULL terminated */ 2199 char zero = '\0'; 2200 2201 if (put_user(zero, ubuf)) 2202 return -EFAULT; 2203 } else if (input_len >= len + 1) { 2204 /* ubuf can hold the string with NULL terminator */ 2205 if (copy_to_user(ubuf, buf, len + 1)) 2206 return -EFAULT; 2207 } else { 2208 /* ubuf cannot hold the string with NULL terminator, 2209 * do a partial copy with NULL terminator. 2210 */ 2211 char zero = '\0'; 2212 2213 err = -ENOSPC; 2214 if (copy_to_user(ubuf, buf, input_len - 1)) 2215 return -EFAULT; 2216 if (put_user(zero, ubuf + input_len - 1)) 2217 return -EFAULT; 2218 } 2219 } 2220 2221 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 2222 put_user(fd_type, &uattr->task_fd_query.fd_type) || 2223 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 2224 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 2225 return -EFAULT; 2226 2227 return err; 2228 } 2229 2230 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 2231 2232 static int bpf_task_fd_query(const union bpf_attr *attr, 2233 union bpf_attr __user *uattr) 2234 { 2235 pid_t pid = attr->task_fd_query.pid; 2236 u32 fd = attr->task_fd_query.fd; 2237 const struct perf_event *event; 2238 struct files_struct *files; 2239 struct task_struct *task; 2240 struct file *file; 2241 int err; 2242 2243 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 2244 return -EINVAL; 2245 2246 if (!capable(CAP_SYS_ADMIN)) 2247 return -EPERM; 2248 2249 if (attr->task_fd_query.flags != 0) 2250 return -EINVAL; 2251 2252 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 2253 if (!task) 2254 return -ENOENT; 2255 2256 files = get_files_struct(task); 2257 put_task_struct(task); 2258 if (!files) 2259 return -ENOENT; 2260 2261 err = 0; 2262 spin_lock(&files->file_lock); 2263 file = fcheck_files(files, fd); 2264 if (!file) 2265 err = -EBADF; 2266 else 2267 get_file(file); 2268 spin_unlock(&files->file_lock); 2269 put_files_struct(files); 2270 2271 if (err) 2272 goto out; 2273 2274 if (file->f_op == &bpf_raw_tp_fops) { 2275 struct bpf_raw_tracepoint *raw_tp = file->private_data; 2276 struct bpf_raw_event_map *btp = raw_tp->btp; 2277 2278 err = bpf_task_fd_query_copy(attr, uattr, 2279 raw_tp->prog->aux->id, 2280 BPF_FD_TYPE_RAW_TRACEPOINT, 2281 btp->tp->name, 0, 0); 2282 goto put_file; 2283 } 2284 2285 event = perf_get_event(file); 2286 if (!IS_ERR(event)) { 2287 u64 probe_offset, probe_addr; 2288 u32 prog_id, fd_type; 2289 const char *buf; 2290 2291 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 2292 &buf, &probe_offset, 2293 &probe_addr); 2294 if (!err) 2295 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 2296 fd_type, buf, 2297 probe_offset, 2298 probe_addr); 2299 goto put_file; 2300 } 2301 2302 err = -ENOTSUPP; 2303 put_file: 2304 fput(file); 2305 out: 2306 return err; 2307 } 2308 2309 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 2310 { 2311 union bpf_attr attr = {}; 2312 int err; 2313 2314 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 2315 return -EPERM; 2316 2317 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 2318 if (err) 2319 return err; 2320 size = min_t(u32, size, sizeof(attr)); 2321 2322 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 2323 if (copy_from_user(&attr, uattr, size) != 0) 2324 return -EFAULT; 2325 2326 err = security_bpf(cmd, &attr, size); 2327 if (err < 0) 2328 return err; 2329 2330 switch (cmd) { 2331 case BPF_MAP_CREATE: 2332 err = map_create(&attr); 2333 break; 2334 case BPF_MAP_LOOKUP_ELEM: 2335 err = map_lookup_elem(&attr); 2336 break; 2337 case BPF_MAP_UPDATE_ELEM: 2338 err = map_update_elem(&attr); 2339 break; 2340 case BPF_MAP_DELETE_ELEM: 2341 err = map_delete_elem(&attr); 2342 break; 2343 case BPF_MAP_GET_NEXT_KEY: 2344 err = map_get_next_key(&attr); 2345 break; 2346 case BPF_PROG_LOAD: 2347 err = bpf_prog_load(&attr); 2348 break; 2349 case BPF_OBJ_PIN: 2350 err = bpf_obj_pin(&attr); 2351 break; 2352 case BPF_OBJ_GET: 2353 err = bpf_obj_get(&attr); 2354 break; 2355 #ifdef CONFIG_CGROUP_BPF 2356 case BPF_PROG_ATTACH: 2357 err = bpf_prog_attach(&attr); 2358 break; 2359 case BPF_PROG_DETACH: 2360 err = bpf_prog_detach(&attr); 2361 break; 2362 case BPF_PROG_QUERY: 2363 err = bpf_prog_query(&attr, uattr); 2364 break; 2365 #endif 2366 case BPF_PROG_TEST_RUN: 2367 err = bpf_prog_test_run(&attr, uattr); 2368 break; 2369 case BPF_PROG_GET_NEXT_ID: 2370 err = bpf_obj_get_next_id(&attr, uattr, 2371 &prog_idr, &prog_idr_lock); 2372 break; 2373 case BPF_MAP_GET_NEXT_ID: 2374 err = bpf_obj_get_next_id(&attr, uattr, 2375 &map_idr, &map_idr_lock); 2376 break; 2377 case BPF_PROG_GET_FD_BY_ID: 2378 err = bpf_prog_get_fd_by_id(&attr); 2379 break; 2380 case BPF_MAP_GET_FD_BY_ID: 2381 err = bpf_map_get_fd_by_id(&attr); 2382 break; 2383 case BPF_OBJ_GET_INFO_BY_FD: 2384 err = bpf_obj_get_info_by_fd(&attr, uattr); 2385 break; 2386 case BPF_RAW_TRACEPOINT_OPEN: 2387 err = bpf_raw_tracepoint_open(&attr); 2388 break; 2389 case BPF_BTF_LOAD: 2390 err = bpf_btf_load(&attr); 2391 break; 2392 case BPF_BTF_GET_FD_BY_ID: 2393 err = bpf_btf_get_fd_by_id(&attr); 2394 break; 2395 case BPF_TASK_FD_QUERY: 2396 err = bpf_task_fd_query(&attr, uattr); 2397 break; 2398 default: 2399 err = -EINVAL; 2400 break; 2401 } 2402 2403 return err; 2404 } 2405