1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 2 * 3 * This program is free software; you can redistribute it and/or 4 * modify it under the terms of version 2 of the GNU General Public 5 * License as published by the Free Software Foundation. 6 * 7 * This program is distributed in the hope that it will be useful, but 8 * WITHOUT ANY WARRANTY; without even the implied warranty of 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 10 * General Public License for more details. 11 */ 12 #include <linux/bpf.h> 13 #include <linux/bpf_trace.h> 14 #include <linux/bpf_lirc.h> 15 #include <linux/btf.h> 16 #include <linux/syscalls.h> 17 #include <linux/slab.h> 18 #include <linux/sched/signal.h> 19 #include <linux/vmalloc.h> 20 #include <linux/mmzone.h> 21 #include <linux/anon_inodes.h> 22 #include <linux/fdtable.h> 23 #include <linux/file.h> 24 #include <linux/fs.h> 25 #include <linux/license.h> 26 #include <linux/filter.h> 27 #include <linux/version.h> 28 #include <linux/kernel.h> 29 #include <linux/idr.h> 30 #include <linux/cred.h> 31 #include <linux/timekeeping.h> 32 #include <linux/ctype.h> 33 #include <linux/btf.h> 34 #include <linux/nospec.h> 35 36 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \ 37 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 38 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 39 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 40 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 41 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map)) 42 43 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 44 45 DEFINE_PER_CPU(int, bpf_prog_active); 46 static DEFINE_IDR(prog_idr); 47 static DEFINE_SPINLOCK(prog_idr_lock); 48 static DEFINE_IDR(map_idr); 49 static DEFINE_SPINLOCK(map_idr_lock); 50 51 int sysctl_unprivileged_bpf_disabled __read_mostly; 52 53 static const struct bpf_map_ops * const bpf_map_types[] = { 54 #define BPF_PROG_TYPE(_id, _ops) 55 #define BPF_MAP_TYPE(_id, _ops) \ 56 [_id] = &_ops, 57 #include <linux/bpf_types.h> 58 #undef BPF_PROG_TYPE 59 #undef BPF_MAP_TYPE 60 }; 61 62 /* 63 * If we're handed a bigger struct than we know of, ensure all the unknown bits 64 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 65 * we don't know about yet. 66 * 67 * There is a ToCToU between this function call and the following 68 * copy_from_user() call. However, this is not a concern since this function is 69 * meant to be a future-proofing of bits. 70 */ 71 int bpf_check_uarg_tail_zero(void __user *uaddr, 72 size_t expected_size, 73 size_t actual_size) 74 { 75 unsigned char __user *addr; 76 unsigned char __user *end; 77 unsigned char val; 78 int err; 79 80 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 81 return -E2BIG; 82 83 if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size))) 84 return -EFAULT; 85 86 if (actual_size <= expected_size) 87 return 0; 88 89 addr = uaddr + expected_size; 90 end = uaddr + actual_size; 91 92 for (; addr < end; addr++) { 93 err = get_user(val, addr); 94 if (err) 95 return err; 96 if (val) 97 return -E2BIG; 98 } 99 100 return 0; 101 } 102 103 const struct bpf_map_ops bpf_map_offload_ops = { 104 .map_alloc = bpf_map_offload_map_alloc, 105 .map_free = bpf_map_offload_map_free, 106 }; 107 108 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 109 { 110 const struct bpf_map_ops *ops; 111 u32 type = attr->map_type; 112 struct bpf_map *map; 113 int err; 114 115 if (type >= ARRAY_SIZE(bpf_map_types)) 116 return ERR_PTR(-EINVAL); 117 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 118 ops = bpf_map_types[type]; 119 if (!ops) 120 return ERR_PTR(-EINVAL); 121 122 if (ops->map_alloc_check) { 123 err = ops->map_alloc_check(attr); 124 if (err) 125 return ERR_PTR(err); 126 } 127 if (attr->map_ifindex) 128 ops = &bpf_map_offload_ops; 129 map = ops->map_alloc(attr); 130 if (IS_ERR(map)) 131 return map; 132 map->ops = ops; 133 map->map_type = type; 134 return map; 135 } 136 137 void *bpf_map_area_alloc(size_t size, int numa_node) 138 { 139 /* We definitely need __GFP_NORETRY, so OOM killer doesn't 140 * trigger under memory pressure as we really just want to 141 * fail instead. 142 */ 143 const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO; 144 void *area; 145 146 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 147 area = kmalloc_node(size, GFP_USER | flags, numa_node); 148 if (area != NULL) 149 return area; 150 } 151 152 return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags, 153 __builtin_return_address(0)); 154 } 155 156 void bpf_map_area_free(void *area) 157 { 158 kvfree(area); 159 } 160 161 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 162 { 163 map->map_type = attr->map_type; 164 map->key_size = attr->key_size; 165 map->value_size = attr->value_size; 166 map->max_entries = attr->max_entries; 167 map->map_flags = attr->map_flags; 168 map->numa_node = bpf_map_attr_numa_node(attr); 169 } 170 171 int bpf_map_precharge_memlock(u32 pages) 172 { 173 struct user_struct *user = get_current_user(); 174 unsigned long memlock_limit, cur; 175 176 memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 177 cur = atomic_long_read(&user->locked_vm); 178 free_uid(user); 179 if (cur + pages > memlock_limit) 180 return -EPERM; 181 return 0; 182 } 183 184 static int bpf_map_charge_memlock(struct bpf_map *map) 185 { 186 struct user_struct *user = get_current_user(); 187 unsigned long memlock_limit; 188 189 memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 190 191 atomic_long_add(map->pages, &user->locked_vm); 192 193 if (atomic_long_read(&user->locked_vm) > memlock_limit) { 194 atomic_long_sub(map->pages, &user->locked_vm); 195 free_uid(user); 196 return -EPERM; 197 } 198 map->user = user; 199 return 0; 200 } 201 202 static void bpf_map_uncharge_memlock(struct bpf_map *map) 203 { 204 struct user_struct *user = map->user; 205 206 atomic_long_sub(map->pages, &user->locked_vm); 207 free_uid(user); 208 } 209 210 static int bpf_map_alloc_id(struct bpf_map *map) 211 { 212 int id; 213 214 idr_preload(GFP_KERNEL); 215 spin_lock_bh(&map_idr_lock); 216 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 217 if (id > 0) 218 map->id = id; 219 spin_unlock_bh(&map_idr_lock); 220 idr_preload_end(); 221 222 if (WARN_ON_ONCE(!id)) 223 return -ENOSPC; 224 225 return id > 0 ? 0 : id; 226 } 227 228 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 229 { 230 unsigned long flags; 231 232 /* Offloaded maps are removed from the IDR store when their device 233 * disappears - even if someone holds an fd to them they are unusable, 234 * the memory is gone, all ops will fail; they are simply waiting for 235 * refcnt to drop to be freed. 236 */ 237 if (!map->id) 238 return; 239 240 if (do_idr_lock) 241 spin_lock_irqsave(&map_idr_lock, flags); 242 else 243 __acquire(&map_idr_lock); 244 245 idr_remove(&map_idr, map->id); 246 map->id = 0; 247 248 if (do_idr_lock) 249 spin_unlock_irqrestore(&map_idr_lock, flags); 250 else 251 __release(&map_idr_lock); 252 } 253 254 /* called from workqueue */ 255 static void bpf_map_free_deferred(struct work_struct *work) 256 { 257 struct bpf_map *map = container_of(work, struct bpf_map, work); 258 259 bpf_map_uncharge_memlock(map); 260 security_bpf_map_free(map); 261 /* implementation dependent freeing */ 262 map->ops->map_free(map); 263 } 264 265 static void bpf_map_put_uref(struct bpf_map *map) 266 { 267 if (atomic_dec_and_test(&map->usercnt)) { 268 if (map->ops->map_release_uref) 269 map->ops->map_release_uref(map); 270 } 271 } 272 273 /* decrement map refcnt and schedule it for freeing via workqueue 274 * (unrelying map implementation ops->map_free() might sleep) 275 */ 276 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 277 { 278 if (atomic_dec_and_test(&map->refcnt)) { 279 /* bpf_map_free_id() must be called first */ 280 bpf_map_free_id(map, do_idr_lock); 281 btf_put(map->btf); 282 INIT_WORK(&map->work, bpf_map_free_deferred); 283 schedule_work(&map->work); 284 } 285 } 286 287 void bpf_map_put(struct bpf_map *map) 288 { 289 __bpf_map_put(map, true); 290 } 291 EXPORT_SYMBOL_GPL(bpf_map_put); 292 293 void bpf_map_put_with_uref(struct bpf_map *map) 294 { 295 bpf_map_put_uref(map); 296 bpf_map_put(map); 297 } 298 299 static int bpf_map_release(struct inode *inode, struct file *filp) 300 { 301 struct bpf_map *map = filp->private_data; 302 303 if (map->ops->map_release) 304 map->ops->map_release(map, filp); 305 306 bpf_map_put_with_uref(map); 307 return 0; 308 } 309 310 #ifdef CONFIG_PROC_FS 311 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 312 { 313 const struct bpf_map *map = filp->private_data; 314 const struct bpf_array *array; 315 u32 owner_prog_type = 0; 316 u32 owner_jited = 0; 317 318 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 319 array = container_of(map, struct bpf_array, map); 320 owner_prog_type = array->owner_prog_type; 321 owner_jited = array->owner_jited; 322 } 323 324 seq_printf(m, 325 "map_type:\t%u\n" 326 "key_size:\t%u\n" 327 "value_size:\t%u\n" 328 "max_entries:\t%u\n" 329 "map_flags:\t%#x\n" 330 "memlock:\t%llu\n", 331 map->map_type, 332 map->key_size, 333 map->value_size, 334 map->max_entries, 335 map->map_flags, 336 map->pages * 1ULL << PAGE_SHIFT); 337 338 if (owner_prog_type) { 339 seq_printf(m, "owner_prog_type:\t%u\n", 340 owner_prog_type); 341 seq_printf(m, "owner_jited:\t%u\n", 342 owner_jited); 343 } 344 } 345 #endif 346 347 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 348 loff_t *ppos) 349 { 350 /* We need this handler such that alloc_file() enables 351 * f_mode with FMODE_CAN_READ. 352 */ 353 return -EINVAL; 354 } 355 356 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 357 size_t siz, loff_t *ppos) 358 { 359 /* We need this handler such that alloc_file() enables 360 * f_mode with FMODE_CAN_WRITE. 361 */ 362 return -EINVAL; 363 } 364 365 const struct file_operations bpf_map_fops = { 366 #ifdef CONFIG_PROC_FS 367 .show_fdinfo = bpf_map_show_fdinfo, 368 #endif 369 .release = bpf_map_release, 370 .read = bpf_dummy_read, 371 .write = bpf_dummy_write, 372 }; 373 374 int bpf_map_new_fd(struct bpf_map *map, int flags) 375 { 376 int ret; 377 378 ret = security_bpf_map(map, OPEN_FMODE(flags)); 379 if (ret < 0) 380 return ret; 381 382 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 383 flags | O_CLOEXEC); 384 } 385 386 int bpf_get_file_flag(int flags) 387 { 388 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 389 return -EINVAL; 390 if (flags & BPF_F_RDONLY) 391 return O_RDONLY; 392 if (flags & BPF_F_WRONLY) 393 return O_WRONLY; 394 return O_RDWR; 395 } 396 397 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 398 #define CHECK_ATTR(CMD) \ 399 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 400 sizeof(attr->CMD##_LAST_FIELD), 0, \ 401 sizeof(*attr) - \ 402 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 403 sizeof(attr->CMD##_LAST_FIELD)) != NULL 404 405 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes. 406 * Return 0 on success and < 0 on error. 407 */ 408 static int bpf_obj_name_cpy(char *dst, const char *src) 409 { 410 const char *end = src + BPF_OBJ_NAME_LEN; 411 412 memset(dst, 0, BPF_OBJ_NAME_LEN); 413 414 /* Copy all isalnum() and '_' char */ 415 while (src < end && *src) { 416 if (!isalnum(*src) && *src != '_') 417 return -EINVAL; 418 *dst++ = *src++; 419 } 420 421 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */ 422 if (src == end) 423 return -EINVAL; 424 425 return 0; 426 } 427 428 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id 429 /* called via syscall */ 430 static int map_create(union bpf_attr *attr) 431 { 432 int numa_node = bpf_map_attr_numa_node(attr); 433 struct bpf_map *map; 434 int f_flags; 435 int err; 436 437 err = CHECK_ATTR(BPF_MAP_CREATE); 438 if (err) 439 return -EINVAL; 440 441 f_flags = bpf_get_file_flag(attr->map_flags); 442 if (f_flags < 0) 443 return f_flags; 444 445 if (numa_node != NUMA_NO_NODE && 446 ((unsigned int)numa_node >= nr_node_ids || 447 !node_online(numa_node))) 448 return -EINVAL; 449 450 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 451 map = find_and_alloc_map(attr); 452 if (IS_ERR(map)) 453 return PTR_ERR(map); 454 455 err = bpf_obj_name_cpy(map->name, attr->map_name); 456 if (err) 457 goto free_map_nouncharge; 458 459 atomic_set(&map->refcnt, 1); 460 atomic_set(&map->usercnt, 1); 461 462 if (bpf_map_support_seq_show(map) && 463 (attr->btf_key_type_id || attr->btf_value_type_id)) { 464 struct btf *btf; 465 466 if (!attr->btf_key_type_id || !attr->btf_value_type_id) { 467 err = -EINVAL; 468 goto free_map_nouncharge; 469 } 470 471 btf = btf_get_by_fd(attr->btf_fd); 472 if (IS_ERR(btf)) { 473 err = PTR_ERR(btf); 474 goto free_map_nouncharge; 475 } 476 477 err = map->ops->map_check_btf(map, btf, attr->btf_key_type_id, 478 attr->btf_value_type_id); 479 if (err) { 480 btf_put(btf); 481 goto free_map_nouncharge; 482 } 483 484 map->btf = btf; 485 map->btf_key_type_id = attr->btf_key_type_id; 486 map->btf_value_type_id = attr->btf_value_type_id; 487 } 488 489 err = security_bpf_map_alloc(map); 490 if (err) 491 goto free_map_nouncharge; 492 493 err = bpf_map_charge_memlock(map); 494 if (err) 495 goto free_map_sec; 496 497 err = bpf_map_alloc_id(map); 498 if (err) 499 goto free_map; 500 501 err = bpf_map_new_fd(map, f_flags); 502 if (err < 0) { 503 /* failed to allocate fd. 504 * bpf_map_put() is needed because the above 505 * bpf_map_alloc_id() has published the map 506 * to the userspace and the userspace may 507 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 508 */ 509 bpf_map_put(map); 510 return err; 511 } 512 513 return err; 514 515 free_map: 516 bpf_map_uncharge_memlock(map); 517 free_map_sec: 518 security_bpf_map_free(map); 519 free_map_nouncharge: 520 btf_put(map->btf); 521 map->ops->map_free(map); 522 return err; 523 } 524 525 /* if error is returned, fd is released. 526 * On success caller should complete fd access with matching fdput() 527 */ 528 struct bpf_map *__bpf_map_get(struct fd f) 529 { 530 if (!f.file) 531 return ERR_PTR(-EBADF); 532 if (f.file->f_op != &bpf_map_fops) { 533 fdput(f); 534 return ERR_PTR(-EINVAL); 535 } 536 537 return f.file->private_data; 538 } 539 540 /* prog's and map's refcnt limit */ 541 #define BPF_MAX_REFCNT 32768 542 543 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) 544 { 545 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { 546 atomic_dec(&map->refcnt); 547 return ERR_PTR(-EBUSY); 548 } 549 if (uref) 550 atomic_inc(&map->usercnt); 551 return map; 552 } 553 EXPORT_SYMBOL_GPL(bpf_map_inc); 554 555 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 556 { 557 struct fd f = fdget(ufd); 558 struct bpf_map *map; 559 560 map = __bpf_map_get(f); 561 if (IS_ERR(map)) 562 return map; 563 564 map = bpf_map_inc(map, true); 565 fdput(f); 566 567 return map; 568 } 569 570 /* map_idr_lock should have been held */ 571 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, 572 bool uref) 573 { 574 int refold; 575 576 refold = __atomic_add_unless(&map->refcnt, 1, 0); 577 578 if (refold >= BPF_MAX_REFCNT) { 579 __bpf_map_put(map, false); 580 return ERR_PTR(-EBUSY); 581 } 582 583 if (!refold) 584 return ERR_PTR(-ENOENT); 585 586 if (uref) 587 atomic_inc(&map->usercnt); 588 589 return map; 590 } 591 592 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 593 { 594 return -ENOTSUPP; 595 } 596 597 /* last field in 'union bpf_attr' used by this command */ 598 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value 599 600 static int map_lookup_elem(union bpf_attr *attr) 601 { 602 void __user *ukey = u64_to_user_ptr(attr->key); 603 void __user *uvalue = u64_to_user_ptr(attr->value); 604 int ufd = attr->map_fd; 605 struct bpf_map *map; 606 void *key, *value, *ptr; 607 u32 value_size; 608 struct fd f; 609 int err; 610 611 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 612 return -EINVAL; 613 614 f = fdget(ufd); 615 map = __bpf_map_get(f); 616 if (IS_ERR(map)) 617 return PTR_ERR(map); 618 619 if (!(f.file->f_mode & FMODE_CAN_READ)) { 620 err = -EPERM; 621 goto err_put; 622 } 623 624 key = memdup_user(ukey, map->key_size); 625 if (IS_ERR(key)) { 626 err = PTR_ERR(key); 627 goto err_put; 628 } 629 630 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 631 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 632 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 633 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 634 else if (IS_FD_MAP(map)) 635 value_size = sizeof(u32); 636 else 637 value_size = map->value_size; 638 639 err = -ENOMEM; 640 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 641 if (!value) 642 goto free_key; 643 644 if (bpf_map_is_dev_bound(map)) { 645 err = bpf_map_offload_lookup_elem(map, key, value); 646 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 647 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 648 err = bpf_percpu_hash_copy(map, key, value); 649 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 650 err = bpf_percpu_array_copy(map, key, value); 651 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 652 err = bpf_stackmap_copy(map, key, value); 653 } else if (IS_FD_ARRAY(map)) { 654 err = bpf_fd_array_map_lookup_elem(map, key, value); 655 } else if (IS_FD_HASH(map)) { 656 err = bpf_fd_htab_map_lookup_elem(map, key, value); 657 } else { 658 rcu_read_lock(); 659 ptr = map->ops->map_lookup_elem(map, key); 660 if (ptr) 661 memcpy(value, ptr, value_size); 662 rcu_read_unlock(); 663 err = ptr ? 0 : -ENOENT; 664 } 665 666 if (err) 667 goto free_value; 668 669 err = -EFAULT; 670 if (copy_to_user(uvalue, value, value_size) != 0) 671 goto free_value; 672 673 err = 0; 674 675 free_value: 676 kfree(value); 677 free_key: 678 kfree(key); 679 err_put: 680 fdput(f); 681 return err; 682 } 683 684 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 685 686 static int map_update_elem(union bpf_attr *attr) 687 { 688 void __user *ukey = u64_to_user_ptr(attr->key); 689 void __user *uvalue = u64_to_user_ptr(attr->value); 690 int ufd = attr->map_fd; 691 struct bpf_map *map; 692 void *key, *value; 693 u32 value_size; 694 struct fd f; 695 int err; 696 697 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 698 return -EINVAL; 699 700 f = fdget(ufd); 701 map = __bpf_map_get(f); 702 if (IS_ERR(map)) 703 return PTR_ERR(map); 704 705 if (!(f.file->f_mode & FMODE_CAN_WRITE)) { 706 err = -EPERM; 707 goto err_put; 708 } 709 710 key = memdup_user(ukey, map->key_size); 711 if (IS_ERR(key)) { 712 err = PTR_ERR(key); 713 goto err_put; 714 } 715 716 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 717 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 718 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 719 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 720 else 721 value_size = map->value_size; 722 723 err = -ENOMEM; 724 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 725 if (!value) 726 goto free_key; 727 728 err = -EFAULT; 729 if (copy_from_user(value, uvalue, value_size) != 0) 730 goto free_value; 731 732 /* Need to create a kthread, thus must support schedule */ 733 if (bpf_map_is_dev_bound(map)) { 734 err = bpf_map_offload_update_elem(map, key, value, attr->flags); 735 goto out; 736 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) { 737 err = map->ops->map_update_elem(map, key, value, attr->flags); 738 goto out; 739 } 740 741 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from 742 * inside bpf map update or delete otherwise deadlocks are possible 743 */ 744 preempt_disable(); 745 __this_cpu_inc(bpf_prog_active); 746 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 747 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 748 err = bpf_percpu_hash_update(map, key, value, attr->flags); 749 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 750 err = bpf_percpu_array_update(map, key, value, attr->flags); 751 } else if (IS_FD_ARRAY(map)) { 752 rcu_read_lock(); 753 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 754 attr->flags); 755 rcu_read_unlock(); 756 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 757 rcu_read_lock(); 758 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 759 attr->flags); 760 rcu_read_unlock(); 761 } else { 762 rcu_read_lock(); 763 err = map->ops->map_update_elem(map, key, value, attr->flags); 764 rcu_read_unlock(); 765 } 766 __this_cpu_dec(bpf_prog_active); 767 preempt_enable(); 768 out: 769 free_value: 770 kfree(value); 771 free_key: 772 kfree(key); 773 err_put: 774 fdput(f); 775 return err; 776 } 777 778 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 779 780 static int map_delete_elem(union bpf_attr *attr) 781 { 782 void __user *ukey = u64_to_user_ptr(attr->key); 783 int ufd = attr->map_fd; 784 struct bpf_map *map; 785 struct fd f; 786 void *key; 787 int err; 788 789 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 790 return -EINVAL; 791 792 f = fdget(ufd); 793 map = __bpf_map_get(f); 794 if (IS_ERR(map)) 795 return PTR_ERR(map); 796 797 if (!(f.file->f_mode & FMODE_CAN_WRITE)) { 798 err = -EPERM; 799 goto err_put; 800 } 801 802 key = memdup_user(ukey, map->key_size); 803 if (IS_ERR(key)) { 804 err = PTR_ERR(key); 805 goto err_put; 806 } 807 808 if (bpf_map_is_dev_bound(map)) { 809 err = bpf_map_offload_delete_elem(map, key); 810 goto out; 811 } 812 813 preempt_disable(); 814 __this_cpu_inc(bpf_prog_active); 815 rcu_read_lock(); 816 err = map->ops->map_delete_elem(map, key); 817 rcu_read_unlock(); 818 __this_cpu_dec(bpf_prog_active); 819 preempt_enable(); 820 out: 821 kfree(key); 822 err_put: 823 fdput(f); 824 return err; 825 } 826 827 /* last field in 'union bpf_attr' used by this command */ 828 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 829 830 static int map_get_next_key(union bpf_attr *attr) 831 { 832 void __user *ukey = u64_to_user_ptr(attr->key); 833 void __user *unext_key = u64_to_user_ptr(attr->next_key); 834 int ufd = attr->map_fd; 835 struct bpf_map *map; 836 void *key, *next_key; 837 struct fd f; 838 int err; 839 840 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 841 return -EINVAL; 842 843 f = fdget(ufd); 844 map = __bpf_map_get(f); 845 if (IS_ERR(map)) 846 return PTR_ERR(map); 847 848 if (!(f.file->f_mode & FMODE_CAN_READ)) { 849 err = -EPERM; 850 goto err_put; 851 } 852 853 if (ukey) { 854 key = memdup_user(ukey, map->key_size); 855 if (IS_ERR(key)) { 856 err = PTR_ERR(key); 857 goto err_put; 858 } 859 } else { 860 key = NULL; 861 } 862 863 err = -ENOMEM; 864 next_key = kmalloc(map->key_size, GFP_USER); 865 if (!next_key) 866 goto free_key; 867 868 if (bpf_map_is_dev_bound(map)) { 869 err = bpf_map_offload_get_next_key(map, key, next_key); 870 goto out; 871 } 872 873 rcu_read_lock(); 874 err = map->ops->map_get_next_key(map, key, next_key); 875 rcu_read_unlock(); 876 out: 877 if (err) 878 goto free_next_key; 879 880 err = -EFAULT; 881 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 882 goto free_next_key; 883 884 err = 0; 885 886 free_next_key: 887 kfree(next_key); 888 free_key: 889 kfree(key); 890 err_put: 891 fdput(f); 892 return err; 893 } 894 895 static const struct bpf_prog_ops * const bpf_prog_types[] = { 896 #define BPF_PROG_TYPE(_id, _name) \ 897 [_id] = & _name ## _prog_ops, 898 #define BPF_MAP_TYPE(_id, _ops) 899 #include <linux/bpf_types.h> 900 #undef BPF_PROG_TYPE 901 #undef BPF_MAP_TYPE 902 }; 903 904 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 905 { 906 const struct bpf_prog_ops *ops; 907 908 if (type >= ARRAY_SIZE(bpf_prog_types)) 909 return -EINVAL; 910 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 911 ops = bpf_prog_types[type]; 912 if (!ops) 913 return -EINVAL; 914 915 if (!bpf_prog_is_dev_bound(prog->aux)) 916 prog->aux->ops = ops; 917 else 918 prog->aux->ops = &bpf_offload_prog_ops; 919 prog->type = type; 920 return 0; 921 } 922 923 /* drop refcnt on maps used by eBPF program and free auxilary data */ 924 static void free_used_maps(struct bpf_prog_aux *aux) 925 { 926 int i; 927 928 for (i = 0; i < aux->used_map_cnt; i++) 929 bpf_map_put(aux->used_maps[i]); 930 931 kfree(aux->used_maps); 932 } 933 934 int __bpf_prog_charge(struct user_struct *user, u32 pages) 935 { 936 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 937 unsigned long user_bufs; 938 939 if (user) { 940 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 941 if (user_bufs > memlock_limit) { 942 atomic_long_sub(pages, &user->locked_vm); 943 return -EPERM; 944 } 945 } 946 947 return 0; 948 } 949 950 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 951 { 952 if (user) 953 atomic_long_sub(pages, &user->locked_vm); 954 } 955 956 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 957 { 958 struct user_struct *user = get_current_user(); 959 int ret; 960 961 ret = __bpf_prog_charge(user, prog->pages); 962 if (ret) { 963 free_uid(user); 964 return ret; 965 } 966 967 prog->aux->user = user; 968 return 0; 969 } 970 971 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 972 { 973 struct user_struct *user = prog->aux->user; 974 975 __bpf_prog_uncharge(user, prog->pages); 976 free_uid(user); 977 } 978 979 static int bpf_prog_alloc_id(struct bpf_prog *prog) 980 { 981 int id; 982 983 idr_preload(GFP_KERNEL); 984 spin_lock_bh(&prog_idr_lock); 985 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 986 if (id > 0) 987 prog->aux->id = id; 988 spin_unlock_bh(&prog_idr_lock); 989 idr_preload_end(); 990 991 /* id is in [1, INT_MAX) */ 992 if (WARN_ON_ONCE(!id)) 993 return -ENOSPC; 994 995 return id > 0 ? 0 : id; 996 } 997 998 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 999 { 1000 /* cBPF to eBPF migrations are currently not in the idr store. 1001 * Offloaded programs are removed from the store when their device 1002 * disappears - even if someone grabs an fd to them they are unusable, 1003 * simply waiting for refcnt to drop to be freed. 1004 */ 1005 if (!prog->aux->id) 1006 return; 1007 1008 if (do_idr_lock) 1009 spin_lock_bh(&prog_idr_lock); 1010 else 1011 __acquire(&prog_idr_lock); 1012 1013 idr_remove(&prog_idr, prog->aux->id); 1014 prog->aux->id = 0; 1015 1016 if (do_idr_lock) 1017 spin_unlock_bh(&prog_idr_lock); 1018 else 1019 __release(&prog_idr_lock); 1020 } 1021 1022 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1023 { 1024 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1025 1026 free_used_maps(aux); 1027 bpf_prog_uncharge_memlock(aux->prog); 1028 security_bpf_prog_free(aux); 1029 bpf_prog_free(aux->prog); 1030 } 1031 1032 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1033 { 1034 if (atomic_dec_and_test(&prog->aux->refcnt)) { 1035 int i; 1036 1037 /* bpf_prog_free_id() must be called first */ 1038 bpf_prog_free_id(prog, do_idr_lock); 1039 1040 for (i = 0; i < prog->aux->func_cnt; i++) 1041 bpf_prog_kallsyms_del(prog->aux->func[i]); 1042 bpf_prog_kallsyms_del(prog); 1043 1044 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1045 } 1046 } 1047 1048 void bpf_prog_put(struct bpf_prog *prog) 1049 { 1050 __bpf_prog_put(prog, true); 1051 } 1052 EXPORT_SYMBOL_GPL(bpf_prog_put); 1053 1054 static int bpf_prog_release(struct inode *inode, struct file *filp) 1055 { 1056 struct bpf_prog *prog = filp->private_data; 1057 1058 bpf_prog_put(prog); 1059 return 0; 1060 } 1061 1062 #ifdef CONFIG_PROC_FS 1063 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1064 { 1065 const struct bpf_prog *prog = filp->private_data; 1066 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1067 1068 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1069 seq_printf(m, 1070 "prog_type:\t%u\n" 1071 "prog_jited:\t%u\n" 1072 "prog_tag:\t%s\n" 1073 "memlock:\t%llu\n", 1074 prog->type, 1075 prog->jited, 1076 prog_tag, 1077 prog->pages * 1ULL << PAGE_SHIFT); 1078 } 1079 #endif 1080 1081 const struct file_operations bpf_prog_fops = { 1082 #ifdef CONFIG_PROC_FS 1083 .show_fdinfo = bpf_prog_show_fdinfo, 1084 #endif 1085 .release = bpf_prog_release, 1086 .read = bpf_dummy_read, 1087 .write = bpf_dummy_write, 1088 }; 1089 1090 int bpf_prog_new_fd(struct bpf_prog *prog) 1091 { 1092 int ret; 1093 1094 ret = security_bpf_prog(prog); 1095 if (ret < 0) 1096 return ret; 1097 1098 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1099 O_RDWR | O_CLOEXEC); 1100 } 1101 1102 static struct bpf_prog *____bpf_prog_get(struct fd f) 1103 { 1104 if (!f.file) 1105 return ERR_PTR(-EBADF); 1106 if (f.file->f_op != &bpf_prog_fops) { 1107 fdput(f); 1108 return ERR_PTR(-EINVAL); 1109 } 1110 1111 return f.file->private_data; 1112 } 1113 1114 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) 1115 { 1116 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) { 1117 atomic_sub(i, &prog->aux->refcnt); 1118 return ERR_PTR(-EBUSY); 1119 } 1120 return prog; 1121 } 1122 EXPORT_SYMBOL_GPL(bpf_prog_add); 1123 1124 void bpf_prog_sub(struct bpf_prog *prog, int i) 1125 { 1126 /* Only to be used for undoing previous bpf_prog_add() in some 1127 * error path. We still know that another entity in our call 1128 * path holds a reference to the program, thus atomic_sub() can 1129 * be safely used in such cases! 1130 */ 1131 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0); 1132 } 1133 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1134 1135 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) 1136 { 1137 return bpf_prog_add(prog, 1); 1138 } 1139 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1140 1141 /* prog_idr_lock should have been held */ 1142 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1143 { 1144 int refold; 1145 1146 refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0); 1147 1148 if (refold >= BPF_MAX_REFCNT) { 1149 __bpf_prog_put(prog, false); 1150 return ERR_PTR(-EBUSY); 1151 } 1152 1153 if (!refold) 1154 return ERR_PTR(-ENOENT); 1155 1156 return prog; 1157 } 1158 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1159 1160 bool bpf_prog_get_ok(struct bpf_prog *prog, 1161 enum bpf_prog_type *attach_type, bool attach_drv) 1162 { 1163 /* not an attachment, just a refcount inc, always allow */ 1164 if (!attach_type) 1165 return true; 1166 1167 if (prog->type != *attach_type) 1168 return false; 1169 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1170 return false; 1171 1172 return true; 1173 } 1174 1175 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1176 bool attach_drv) 1177 { 1178 struct fd f = fdget(ufd); 1179 struct bpf_prog *prog; 1180 1181 prog = ____bpf_prog_get(f); 1182 if (IS_ERR(prog)) 1183 return prog; 1184 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1185 prog = ERR_PTR(-EINVAL); 1186 goto out; 1187 } 1188 1189 prog = bpf_prog_inc(prog); 1190 out: 1191 fdput(f); 1192 return prog; 1193 } 1194 1195 struct bpf_prog *bpf_prog_get(u32 ufd) 1196 { 1197 return __bpf_prog_get(ufd, NULL, false); 1198 } 1199 1200 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1201 bool attach_drv) 1202 { 1203 return __bpf_prog_get(ufd, &type, attach_drv); 1204 } 1205 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1206 1207 /* Initially all BPF programs could be loaded w/o specifying 1208 * expected_attach_type. Later for some of them specifying expected_attach_type 1209 * at load time became required so that program could be validated properly. 1210 * Programs of types that are allowed to be loaded both w/ and w/o (for 1211 * backward compatibility) expected_attach_type, should have the default attach 1212 * type assigned to expected_attach_type for the latter case, so that it can be 1213 * validated later at attach time. 1214 * 1215 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1216 * prog type requires it but has some attach types that have to be backward 1217 * compatible. 1218 */ 1219 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1220 { 1221 switch (attr->prog_type) { 1222 case BPF_PROG_TYPE_CGROUP_SOCK: 1223 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1224 * exist so checking for non-zero is the way to go here. 1225 */ 1226 if (!attr->expected_attach_type) 1227 attr->expected_attach_type = 1228 BPF_CGROUP_INET_SOCK_CREATE; 1229 break; 1230 } 1231 } 1232 1233 static int 1234 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type, 1235 enum bpf_attach_type expected_attach_type) 1236 { 1237 switch (prog_type) { 1238 case BPF_PROG_TYPE_CGROUP_SOCK: 1239 switch (expected_attach_type) { 1240 case BPF_CGROUP_INET_SOCK_CREATE: 1241 case BPF_CGROUP_INET4_POST_BIND: 1242 case BPF_CGROUP_INET6_POST_BIND: 1243 return 0; 1244 default: 1245 return -EINVAL; 1246 } 1247 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1248 switch (expected_attach_type) { 1249 case BPF_CGROUP_INET4_BIND: 1250 case BPF_CGROUP_INET6_BIND: 1251 case BPF_CGROUP_INET4_CONNECT: 1252 case BPF_CGROUP_INET6_CONNECT: 1253 case BPF_CGROUP_UDP4_SENDMSG: 1254 case BPF_CGROUP_UDP6_SENDMSG: 1255 return 0; 1256 default: 1257 return -EINVAL; 1258 } 1259 default: 1260 return 0; 1261 } 1262 } 1263 1264 /* last field in 'union bpf_attr' used by this command */ 1265 #define BPF_PROG_LOAD_LAST_FIELD expected_attach_type 1266 1267 static int bpf_prog_load(union bpf_attr *attr) 1268 { 1269 enum bpf_prog_type type = attr->prog_type; 1270 struct bpf_prog *prog; 1271 int err; 1272 char license[128]; 1273 bool is_gpl; 1274 1275 if (CHECK_ATTR(BPF_PROG_LOAD)) 1276 return -EINVAL; 1277 1278 if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT) 1279 return -EINVAL; 1280 1281 /* copy eBPF program license from user space */ 1282 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 1283 sizeof(license) - 1) < 0) 1284 return -EFAULT; 1285 license[sizeof(license) - 1] = 0; 1286 1287 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 1288 is_gpl = license_is_gpl_compatible(license); 1289 1290 if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS) 1291 return -E2BIG; 1292 1293 if (type == BPF_PROG_TYPE_KPROBE && 1294 attr->kern_version != LINUX_VERSION_CODE) 1295 return -EINVAL; 1296 1297 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 1298 type != BPF_PROG_TYPE_CGROUP_SKB && 1299 !capable(CAP_SYS_ADMIN)) 1300 return -EPERM; 1301 1302 bpf_prog_load_fixup_attach_type(attr); 1303 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type)) 1304 return -EINVAL; 1305 1306 /* plain bpf_prog allocation */ 1307 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 1308 if (!prog) 1309 return -ENOMEM; 1310 1311 prog->expected_attach_type = attr->expected_attach_type; 1312 1313 prog->aux->offload_requested = !!attr->prog_ifindex; 1314 1315 err = security_bpf_prog_alloc(prog->aux); 1316 if (err) 1317 goto free_prog_nouncharge; 1318 1319 err = bpf_prog_charge_memlock(prog); 1320 if (err) 1321 goto free_prog_sec; 1322 1323 prog->len = attr->insn_cnt; 1324 1325 err = -EFAULT; 1326 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 1327 bpf_prog_insn_size(prog)) != 0) 1328 goto free_prog; 1329 1330 prog->orig_prog = NULL; 1331 prog->jited = 0; 1332 1333 atomic_set(&prog->aux->refcnt, 1); 1334 prog->gpl_compatible = is_gpl ? 1 : 0; 1335 1336 if (bpf_prog_is_dev_bound(prog->aux)) { 1337 err = bpf_prog_offload_init(prog, attr); 1338 if (err) 1339 goto free_prog; 1340 } 1341 1342 /* find program type: socket_filter vs tracing_filter */ 1343 err = find_prog_type(type, prog); 1344 if (err < 0) 1345 goto free_prog; 1346 1347 prog->aux->load_time = ktime_get_boot_ns(); 1348 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 1349 if (err) 1350 goto free_prog; 1351 1352 /* run eBPF verifier */ 1353 err = bpf_check(&prog, attr); 1354 if (err < 0) 1355 goto free_used_maps; 1356 1357 /* eBPF program is ready to be JITed */ 1358 if (!prog->bpf_func) 1359 prog = bpf_prog_select_runtime(prog, &err); 1360 if (err < 0) 1361 goto free_used_maps; 1362 1363 err = bpf_prog_alloc_id(prog); 1364 if (err) 1365 goto free_used_maps; 1366 1367 err = bpf_prog_new_fd(prog); 1368 if (err < 0) { 1369 /* failed to allocate fd. 1370 * bpf_prog_put() is needed because the above 1371 * bpf_prog_alloc_id() has published the prog 1372 * to the userspace and the userspace may 1373 * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID. 1374 */ 1375 bpf_prog_put(prog); 1376 return err; 1377 } 1378 1379 bpf_prog_kallsyms_add(prog); 1380 return err; 1381 1382 free_used_maps: 1383 free_used_maps(prog->aux); 1384 free_prog: 1385 bpf_prog_uncharge_memlock(prog); 1386 free_prog_sec: 1387 security_bpf_prog_free(prog->aux); 1388 free_prog_nouncharge: 1389 bpf_prog_free(prog); 1390 return err; 1391 } 1392 1393 #define BPF_OBJ_LAST_FIELD file_flags 1394 1395 static int bpf_obj_pin(const union bpf_attr *attr) 1396 { 1397 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 1398 return -EINVAL; 1399 1400 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 1401 } 1402 1403 static int bpf_obj_get(const union bpf_attr *attr) 1404 { 1405 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 1406 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 1407 return -EINVAL; 1408 1409 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 1410 attr->file_flags); 1411 } 1412 1413 struct bpf_raw_tracepoint { 1414 struct bpf_raw_event_map *btp; 1415 struct bpf_prog *prog; 1416 }; 1417 1418 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) 1419 { 1420 struct bpf_raw_tracepoint *raw_tp = filp->private_data; 1421 1422 if (raw_tp->prog) { 1423 bpf_probe_unregister(raw_tp->btp, raw_tp->prog); 1424 bpf_prog_put(raw_tp->prog); 1425 } 1426 kfree(raw_tp); 1427 return 0; 1428 } 1429 1430 static const struct file_operations bpf_raw_tp_fops = { 1431 .release = bpf_raw_tracepoint_release, 1432 .read = bpf_dummy_read, 1433 .write = bpf_dummy_write, 1434 }; 1435 1436 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 1437 1438 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 1439 { 1440 struct bpf_raw_tracepoint *raw_tp; 1441 struct bpf_raw_event_map *btp; 1442 struct bpf_prog *prog; 1443 char tp_name[128]; 1444 int tp_fd, err; 1445 1446 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name), 1447 sizeof(tp_name) - 1) < 0) 1448 return -EFAULT; 1449 tp_name[sizeof(tp_name) - 1] = 0; 1450 1451 btp = bpf_find_raw_tracepoint(tp_name); 1452 if (!btp) 1453 return -ENOENT; 1454 1455 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 1456 if (!raw_tp) 1457 return -ENOMEM; 1458 raw_tp->btp = btp; 1459 1460 prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd, 1461 BPF_PROG_TYPE_RAW_TRACEPOINT); 1462 if (IS_ERR(prog)) { 1463 err = PTR_ERR(prog); 1464 goto out_free_tp; 1465 } 1466 1467 err = bpf_probe_register(raw_tp->btp, prog); 1468 if (err) 1469 goto out_put_prog; 1470 1471 raw_tp->prog = prog; 1472 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp, 1473 O_CLOEXEC); 1474 if (tp_fd < 0) { 1475 bpf_probe_unregister(raw_tp->btp, prog); 1476 err = tp_fd; 1477 goto out_put_prog; 1478 } 1479 return tp_fd; 1480 1481 out_put_prog: 1482 bpf_prog_put(prog); 1483 out_free_tp: 1484 kfree(raw_tp); 1485 return err; 1486 } 1487 1488 #ifdef CONFIG_CGROUP_BPF 1489 1490 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 1491 enum bpf_attach_type attach_type) 1492 { 1493 switch (prog->type) { 1494 case BPF_PROG_TYPE_CGROUP_SOCK: 1495 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1496 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 1497 default: 1498 return 0; 1499 } 1500 } 1501 1502 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags 1503 1504 static int sockmap_get_from_fd(const union bpf_attr *attr, 1505 int type, bool attach) 1506 { 1507 struct bpf_prog *prog = NULL; 1508 int ufd = attr->target_fd; 1509 struct bpf_map *map; 1510 struct fd f; 1511 int err; 1512 1513 f = fdget(ufd); 1514 map = __bpf_map_get(f); 1515 if (IS_ERR(map)) 1516 return PTR_ERR(map); 1517 1518 if (attach) { 1519 prog = bpf_prog_get_type(attr->attach_bpf_fd, type); 1520 if (IS_ERR(prog)) { 1521 fdput(f); 1522 return PTR_ERR(prog); 1523 } 1524 } 1525 1526 err = sock_map_prog(map, prog, attr->attach_type); 1527 if (err) { 1528 fdput(f); 1529 if (prog) 1530 bpf_prog_put(prog); 1531 return err; 1532 } 1533 1534 fdput(f); 1535 return 0; 1536 } 1537 1538 #define BPF_F_ATTACH_MASK \ 1539 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) 1540 1541 static int bpf_prog_attach(const union bpf_attr *attr) 1542 { 1543 enum bpf_prog_type ptype; 1544 struct bpf_prog *prog; 1545 struct cgroup *cgrp; 1546 int ret; 1547 1548 if (!capable(CAP_NET_ADMIN)) 1549 return -EPERM; 1550 1551 if (CHECK_ATTR(BPF_PROG_ATTACH)) 1552 return -EINVAL; 1553 1554 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 1555 return -EINVAL; 1556 1557 switch (attr->attach_type) { 1558 case BPF_CGROUP_INET_INGRESS: 1559 case BPF_CGROUP_INET_EGRESS: 1560 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1561 break; 1562 case BPF_CGROUP_INET_SOCK_CREATE: 1563 case BPF_CGROUP_INET4_POST_BIND: 1564 case BPF_CGROUP_INET6_POST_BIND: 1565 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1566 break; 1567 case BPF_CGROUP_INET4_BIND: 1568 case BPF_CGROUP_INET6_BIND: 1569 case BPF_CGROUP_INET4_CONNECT: 1570 case BPF_CGROUP_INET6_CONNECT: 1571 case BPF_CGROUP_UDP4_SENDMSG: 1572 case BPF_CGROUP_UDP6_SENDMSG: 1573 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1574 break; 1575 case BPF_CGROUP_SOCK_OPS: 1576 ptype = BPF_PROG_TYPE_SOCK_OPS; 1577 break; 1578 case BPF_CGROUP_DEVICE: 1579 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1580 break; 1581 case BPF_SK_MSG_VERDICT: 1582 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, true); 1583 case BPF_SK_SKB_STREAM_PARSER: 1584 case BPF_SK_SKB_STREAM_VERDICT: 1585 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, true); 1586 case BPF_LIRC_MODE2: 1587 return lirc_prog_attach(attr); 1588 default: 1589 return -EINVAL; 1590 } 1591 1592 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1593 if (IS_ERR(prog)) 1594 return PTR_ERR(prog); 1595 1596 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 1597 bpf_prog_put(prog); 1598 return -EINVAL; 1599 } 1600 1601 cgrp = cgroup_get_from_fd(attr->target_fd); 1602 if (IS_ERR(cgrp)) { 1603 bpf_prog_put(prog); 1604 return PTR_ERR(cgrp); 1605 } 1606 1607 ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type, 1608 attr->attach_flags); 1609 if (ret) 1610 bpf_prog_put(prog); 1611 cgroup_put(cgrp); 1612 1613 return ret; 1614 } 1615 1616 #define BPF_PROG_DETACH_LAST_FIELD attach_type 1617 1618 static int bpf_prog_detach(const union bpf_attr *attr) 1619 { 1620 enum bpf_prog_type ptype; 1621 struct bpf_prog *prog; 1622 struct cgroup *cgrp; 1623 int ret; 1624 1625 if (!capable(CAP_NET_ADMIN)) 1626 return -EPERM; 1627 1628 if (CHECK_ATTR(BPF_PROG_DETACH)) 1629 return -EINVAL; 1630 1631 switch (attr->attach_type) { 1632 case BPF_CGROUP_INET_INGRESS: 1633 case BPF_CGROUP_INET_EGRESS: 1634 ptype = BPF_PROG_TYPE_CGROUP_SKB; 1635 break; 1636 case BPF_CGROUP_INET_SOCK_CREATE: 1637 case BPF_CGROUP_INET4_POST_BIND: 1638 case BPF_CGROUP_INET6_POST_BIND: 1639 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 1640 break; 1641 case BPF_CGROUP_INET4_BIND: 1642 case BPF_CGROUP_INET6_BIND: 1643 case BPF_CGROUP_INET4_CONNECT: 1644 case BPF_CGROUP_INET6_CONNECT: 1645 case BPF_CGROUP_UDP4_SENDMSG: 1646 case BPF_CGROUP_UDP6_SENDMSG: 1647 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 1648 break; 1649 case BPF_CGROUP_SOCK_OPS: 1650 ptype = BPF_PROG_TYPE_SOCK_OPS; 1651 break; 1652 case BPF_CGROUP_DEVICE: 1653 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 1654 break; 1655 case BPF_SK_MSG_VERDICT: 1656 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, false); 1657 case BPF_SK_SKB_STREAM_PARSER: 1658 case BPF_SK_SKB_STREAM_VERDICT: 1659 return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, false); 1660 case BPF_LIRC_MODE2: 1661 return lirc_prog_detach(attr); 1662 default: 1663 return -EINVAL; 1664 } 1665 1666 cgrp = cgroup_get_from_fd(attr->target_fd); 1667 if (IS_ERR(cgrp)) 1668 return PTR_ERR(cgrp); 1669 1670 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 1671 if (IS_ERR(prog)) 1672 prog = NULL; 1673 1674 ret = cgroup_bpf_detach(cgrp, prog, attr->attach_type, 0); 1675 if (prog) 1676 bpf_prog_put(prog); 1677 cgroup_put(cgrp); 1678 return ret; 1679 } 1680 1681 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 1682 1683 static int bpf_prog_query(const union bpf_attr *attr, 1684 union bpf_attr __user *uattr) 1685 { 1686 struct cgroup *cgrp; 1687 int ret; 1688 1689 if (!capable(CAP_NET_ADMIN)) 1690 return -EPERM; 1691 if (CHECK_ATTR(BPF_PROG_QUERY)) 1692 return -EINVAL; 1693 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 1694 return -EINVAL; 1695 1696 switch (attr->query.attach_type) { 1697 case BPF_CGROUP_INET_INGRESS: 1698 case BPF_CGROUP_INET_EGRESS: 1699 case BPF_CGROUP_INET_SOCK_CREATE: 1700 case BPF_CGROUP_INET4_BIND: 1701 case BPF_CGROUP_INET6_BIND: 1702 case BPF_CGROUP_INET4_POST_BIND: 1703 case BPF_CGROUP_INET6_POST_BIND: 1704 case BPF_CGROUP_INET4_CONNECT: 1705 case BPF_CGROUP_INET6_CONNECT: 1706 case BPF_CGROUP_UDP4_SENDMSG: 1707 case BPF_CGROUP_UDP6_SENDMSG: 1708 case BPF_CGROUP_SOCK_OPS: 1709 case BPF_CGROUP_DEVICE: 1710 break; 1711 case BPF_LIRC_MODE2: 1712 return lirc_prog_query(attr, uattr); 1713 default: 1714 return -EINVAL; 1715 } 1716 cgrp = cgroup_get_from_fd(attr->query.target_fd); 1717 if (IS_ERR(cgrp)) 1718 return PTR_ERR(cgrp); 1719 ret = cgroup_bpf_query(cgrp, attr, uattr); 1720 cgroup_put(cgrp); 1721 return ret; 1722 } 1723 #endif /* CONFIG_CGROUP_BPF */ 1724 1725 #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration 1726 1727 static int bpf_prog_test_run(const union bpf_attr *attr, 1728 union bpf_attr __user *uattr) 1729 { 1730 struct bpf_prog *prog; 1731 int ret = -ENOTSUPP; 1732 1733 if (!capable(CAP_SYS_ADMIN)) 1734 return -EPERM; 1735 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 1736 return -EINVAL; 1737 1738 prog = bpf_prog_get(attr->test.prog_fd); 1739 if (IS_ERR(prog)) 1740 return PTR_ERR(prog); 1741 1742 if (prog->aux->ops->test_run) 1743 ret = prog->aux->ops->test_run(prog, attr, uattr); 1744 1745 bpf_prog_put(prog); 1746 return ret; 1747 } 1748 1749 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 1750 1751 static int bpf_obj_get_next_id(const union bpf_attr *attr, 1752 union bpf_attr __user *uattr, 1753 struct idr *idr, 1754 spinlock_t *lock) 1755 { 1756 u32 next_id = attr->start_id; 1757 int err = 0; 1758 1759 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 1760 return -EINVAL; 1761 1762 if (!capable(CAP_SYS_ADMIN)) 1763 return -EPERM; 1764 1765 next_id++; 1766 spin_lock_bh(lock); 1767 if (!idr_get_next(idr, &next_id)) 1768 err = -ENOENT; 1769 spin_unlock_bh(lock); 1770 1771 if (!err) 1772 err = put_user(next_id, &uattr->next_id); 1773 1774 return err; 1775 } 1776 1777 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 1778 1779 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 1780 { 1781 struct bpf_prog *prog; 1782 u32 id = attr->prog_id; 1783 int fd; 1784 1785 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 1786 return -EINVAL; 1787 1788 if (!capable(CAP_SYS_ADMIN)) 1789 return -EPERM; 1790 1791 spin_lock_bh(&prog_idr_lock); 1792 prog = idr_find(&prog_idr, id); 1793 if (prog) 1794 prog = bpf_prog_inc_not_zero(prog); 1795 else 1796 prog = ERR_PTR(-ENOENT); 1797 spin_unlock_bh(&prog_idr_lock); 1798 1799 if (IS_ERR(prog)) 1800 return PTR_ERR(prog); 1801 1802 fd = bpf_prog_new_fd(prog); 1803 if (fd < 0) 1804 bpf_prog_put(prog); 1805 1806 return fd; 1807 } 1808 1809 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 1810 1811 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 1812 { 1813 struct bpf_map *map; 1814 u32 id = attr->map_id; 1815 int f_flags; 1816 int fd; 1817 1818 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 1819 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 1820 return -EINVAL; 1821 1822 if (!capable(CAP_SYS_ADMIN)) 1823 return -EPERM; 1824 1825 f_flags = bpf_get_file_flag(attr->open_flags); 1826 if (f_flags < 0) 1827 return f_flags; 1828 1829 spin_lock_bh(&map_idr_lock); 1830 map = idr_find(&map_idr, id); 1831 if (map) 1832 map = bpf_map_inc_not_zero(map, true); 1833 else 1834 map = ERR_PTR(-ENOENT); 1835 spin_unlock_bh(&map_idr_lock); 1836 1837 if (IS_ERR(map)) 1838 return PTR_ERR(map); 1839 1840 fd = bpf_map_new_fd(map, f_flags); 1841 if (fd < 0) 1842 bpf_map_put(map); 1843 1844 return fd; 1845 } 1846 1847 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 1848 unsigned long addr) 1849 { 1850 int i; 1851 1852 for (i = 0; i < prog->aux->used_map_cnt; i++) 1853 if (prog->aux->used_maps[i] == (void *)addr) 1854 return prog->aux->used_maps[i]; 1855 return NULL; 1856 } 1857 1858 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 1859 { 1860 const struct bpf_map *map; 1861 struct bpf_insn *insns; 1862 u64 imm; 1863 int i; 1864 1865 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 1866 GFP_USER); 1867 if (!insns) 1868 return insns; 1869 1870 for (i = 0; i < prog->len; i++) { 1871 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 1872 insns[i].code = BPF_JMP | BPF_CALL; 1873 insns[i].imm = BPF_FUNC_tail_call; 1874 /* fall-through */ 1875 } 1876 if (insns[i].code == (BPF_JMP | BPF_CALL) || 1877 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 1878 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 1879 insns[i].code = BPF_JMP | BPF_CALL; 1880 if (!bpf_dump_raw_ok()) 1881 insns[i].imm = 0; 1882 continue; 1883 } 1884 1885 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 1886 continue; 1887 1888 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 1889 map = bpf_map_from_imm(prog, imm); 1890 if (map) { 1891 insns[i].src_reg = BPF_PSEUDO_MAP_FD; 1892 insns[i].imm = map->id; 1893 insns[i + 1].imm = 0; 1894 continue; 1895 } 1896 1897 if (!bpf_dump_raw_ok() && 1898 imm == (unsigned long)prog->aux) { 1899 insns[i].imm = 0; 1900 insns[i + 1].imm = 0; 1901 continue; 1902 } 1903 } 1904 1905 return insns; 1906 } 1907 1908 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 1909 const union bpf_attr *attr, 1910 union bpf_attr __user *uattr) 1911 { 1912 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 1913 struct bpf_prog_info info = {}; 1914 u32 info_len = attr->info.info_len; 1915 char __user *uinsns; 1916 u32 ulen; 1917 int err; 1918 1919 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 1920 if (err) 1921 return err; 1922 info_len = min_t(u32, sizeof(info), info_len); 1923 1924 if (copy_from_user(&info, uinfo, info_len)) 1925 return -EFAULT; 1926 1927 info.type = prog->type; 1928 info.id = prog->aux->id; 1929 info.load_time = prog->aux->load_time; 1930 info.created_by_uid = from_kuid_munged(current_user_ns(), 1931 prog->aux->user->uid); 1932 info.gpl_compatible = prog->gpl_compatible; 1933 1934 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 1935 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 1936 1937 ulen = info.nr_map_ids; 1938 info.nr_map_ids = prog->aux->used_map_cnt; 1939 ulen = min_t(u32, info.nr_map_ids, ulen); 1940 if (ulen) { 1941 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 1942 u32 i; 1943 1944 for (i = 0; i < ulen; i++) 1945 if (put_user(prog->aux->used_maps[i]->id, 1946 &user_map_ids[i])) 1947 return -EFAULT; 1948 } 1949 1950 if (!capable(CAP_SYS_ADMIN)) { 1951 info.jited_prog_len = 0; 1952 info.xlated_prog_len = 0; 1953 info.nr_jited_ksyms = 0; 1954 goto done; 1955 } 1956 1957 ulen = info.xlated_prog_len; 1958 info.xlated_prog_len = bpf_prog_insn_size(prog); 1959 if (info.xlated_prog_len && ulen) { 1960 struct bpf_insn *insns_sanitized; 1961 bool fault; 1962 1963 if (prog->blinded && !bpf_dump_raw_ok()) { 1964 info.xlated_prog_insns = 0; 1965 goto done; 1966 } 1967 insns_sanitized = bpf_insn_prepare_dump(prog); 1968 if (!insns_sanitized) 1969 return -ENOMEM; 1970 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 1971 ulen = min_t(u32, info.xlated_prog_len, ulen); 1972 fault = copy_to_user(uinsns, insns_sanitized, ulen); 1973 kfree(insns_sanitized); 1974 if (fault) 1975 return -EFAULT; 1976 } 1977 1978 if (bpf_prog_is_dev_bound(prog->aux)) { 1979 err = bpf_prog_offload_info_fill(&info, prog); 1980 if (err) 1981 return err; 1982 goto done; 1983 } 1984 1985 /* NOTE: the following code is supposed to be skipped for offload. 1986 * bpf_prog_offload_info_fill() is the place to fill similar fields 1987 * for offload. 1988 */ 1989 ulen = info.jited_prog_len; 1990 if (prog->aux->func_cnt) { 1991 u32 i; 1992 1993 info.jited_prog_len = 0; 1994 for (i = 0; i < prog->aux->func_cnt; i++) 1995 info.jited_prog_len += prog->aux->func[i]->jited_len; 1996 } else { 1997 info.jited_prog_len = prog->jited_len; 1998 } 1999 2000 if (info.jited_prog_len && ulen) { 2001 if (bpf_dump_raw_ok()) { 2002 uinsns = u64_to_user_ptr(info.jited_prog_insns); 2003 ulen = min_t(u32, info.jited_prog_len, ulen); 2004 2005 /* for multi-function programs, copy the JITed 2006 * instructions for all the functions 2007 */ 2008 if (prog->aux->func_cnt) { 2009 u32 len, free, i; 2010 u8 *img; 2011 2012 free = ulen; 2013 for (i = 0; i < prog->aux->func_cnt; i++) { 2014 len = prog->aux->func[i]->jited_len; 2015 len = min_t(u32, len, free); 2016 img = (u8 *) prog->aux->func[i]->bpf_func; 2017 if (copy_to_user(uinsns, img, len)) 2018 return -EFAULT; 2019 uinsns += len; 2020 free -= len; 2021 if (!free) 2022 break; 2023 } 2024 } else { 2025 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 2026 return -EFAULT; 2027 } 2028 } else { 2029 info.jited_prog_insns = 0; 2030 } 2031 } 2032 2033 ulen = info.nr_jited_ksyms; 2034 info.nr_jited_ksyms = prog->aux->func_cnt; 2035 if (info.nr_jited_ksyms && ulen) { 2036 if (bpf_dump_raw_ok()) { 2037 u64 __user *user_ksyms; 2038 ulong ksym_addr; 2039 u32 i; 2040 2041 /* copy the address of the kernel symbol 2042 * corresponding to each function 2043 */ 2044 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 2045 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 2046 for (i = 0; i < ulen; i++) { 2047 ksym_addr = (ulong) prog->aux->func[i]->bpf_func; 2048 ksym_addr &= PAGE_MASK; 2049 if (put_user((u64) ksym_addr, &user_ksyms[i])) 2050 return -EFAULT; 2051 } 2052 } else { 2053 info.jited_ksyms = 0; 2054 } 2055 } 2056 2057 ulen = info.nr_jited_func_lens; 2058 info.nr_jited_func_lens = prog->aux->func_cnt; 2059 if (info.nr_jited_func_lens && ulen) { 2060 if (bpf_dump_raw_ok()) { 2061 u32 __user *user_lens; 2062 u32 func_len, i; 2063 2064 /* copy the JITed image lengths for each function */ 2065 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 2066 user_lens = u64_to_user_ptr(info.jited_func_lens); 2067 for (i = 0; i < ulen; i++) { 2068 func_len = prog->aux->func[i]->jited_len; 2069 if (put_user(func_len, &user_lens[i])) 2070 return -EFAULT; 2071 } 2072 } else { 2073 info.jited_func_lens = 0; 2074 } 2075 } 2076 2077 done: 2078 if (copy_to_user(uinfo, &info, info_len) || 2079 put_user(info_len, &uattr->info.info_len)) 2080 return -EFAULT; 2081 2082 return 0; 2083 } 2084 2085 static int bpf_map_get_info_by_fd(struct bpf_map *map, 2086 const union bpf_attr *attr, 2087 union bpf_attr __user *uattr) 2088 { 2089 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2090 struct bpf_map_info info = {}; 2091 u32 info_len = attr->info.info_len; 2092 int err; 2093 2094 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2095 if (err) 2096 return err; 2097 info_len = min_t(u32, sizeof(info), info_len); 2098 2099 info.type = map->map_type; 2100 info.id = map->id; 2101 info.key_size = map->key_size; 2102 info.value_size = map->value_size; 2103 info.max_entries = map->max_entries; 2104 info.map_flags = map->map_flags; 2105 memcpy(info.name, map->name, sizeof(map->name)); 2106 2107 if (map->btf) { 2108 info.btf_id = btf_id(map->btf); 2109 info.btf_key_type_id = map->btf_key_type_id; 2110 info.btf_value_type_id = map->btf_value_type_id; 2111 } 2112 2113 if (bpf_map_is_dev_bound(map)) { 2114 err = bpf_map_offload_info_fill(&info, map); 2115 if (err) 2116 return err; 2117 } 2118 2119 if (copy_to_user(uinfo, &info, info_len) || 2120 put_user(info_len, &uattr->info.info_len)) 2121 return -EFAULT; 2122 2123 return 0; 2124 } 2125 2126 static int bpf_btf_get_info_by_fd(struct btf *btf, 2127 const union bpf_attr *attr, 2128 union bpf_attr __user *uattr) 2129 { 2130 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2131 u32 info_len = attr->info.info_len; 2132 int err; 2133 2134 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 2135 if (err) 2136 return err; 2137 2138 return btf_get_info_by_fd(btf, attr, uattr); 2139 } 2140 2141 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 2142 2143 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 2144 union bpf_attr __user *uattr) 2145 { 2146 int ufd = attr->info.bpf_fd; 2147 struct fd f; 2148 int err; 2149 2150 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 2151 return -EINVAL; 2152 2153 f = fdget(ufd); 2154 if (!f.file) 2155 return -EBADFD; 2156 2157 if (f.file->f_op == &bpf_prog_fops) 2158 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 2159 uattr); 2160 else if (f.file->f_op == &bpf_map_fops) 2161 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 2162 uattr); 2163 else if (f.file->f_op == &btf_fops) 2164 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 2165 else 2166 err = -EINVAL; 2167 2168 fdput(f); 2169 return err; 2170 } 2171 2172 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 2173 2174 static int bpf_btf_load(const union bpf_attr *attr) 2175 { 2176 if (CHECK_ATTR(BPF_BTF_LOAD)) 2177 return -EINVAL; 2178 2179 if (!capable(CAP_SYS_ADMIN)) 2180 return -EPERM; 2181 2182 return btf_new_fd(attr); 2183 } 2184 2185 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 2186 2187 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 2188 { 2189 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 2190 return -EINVAL; 2191 2192 if (!capable(CAP_SYS_ADMIN)) 2193 return -EPERM; 2194 2195 return btf_get_fd_by_id(attr->btf_id); 2196 } 2197 2198 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 2199 union bpf_attr __user *uattr, 2200 u32 prog_id, u32 fd_type, 2201 const char *buf, u64 probe_offset, 2202 u64 probe_addr) 2203 { 2204 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 2205 u32 len = buf ? strlen(buf) : 0, input_len; 2206 int err = 0; 2207 2208 if (put_user(len, &uattr->task_fd_query.buf_len)) 2209 return -EFAULT; 2210 input_len = attr->task_fd_query.buf_len; 2211 if (input_len && ubuf) { 2212 if (!len) { 2213 /* nothing to copy, just make ubuf NULL terminated */ 2214 char zero = '\0'; 2215 2216 if (put_user(zero, ubuf)) 2217 return -EFAULT; 2218 } else if (input_len >= len + 1) { 2219 /* ubuf can hold the string with NULL terminator */ 2220 if (copy_to_user(ubuf, buf, len + 1)) 2221 return -EFAULT; 2222 } else { 2223 /* ubuf cannot hold the string with NULL terminator, 2224 * do a partial copy with NULL terminator. 2225 */ 2226 char zero = '\0'; 2227 2228 err = -ENOSPC; 2229 if (copy_to_user(ubuf, buf, input_len - 1)) 2230 return -EFAULT; 2231 if (put_user(zero, ubuf + input_len - 1)) 2232 return -EFAULT; 2233 } 2234 } 2235 2236 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 2237 put_user(fd_type, &uattr->task_fd_query.fd_type) || 2238 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 2239 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 2240 return -EFAULT; 2241 2242 return err; 2243 } 2244 2245 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 2246 2247 static int bpf_task_fd_query(const union bpf_attr *attr, 2248 union bpf_attr __user *uattr) 2249 { 2250 pid_t pid = attr->task_fd_query.pid; 2251 u32 fd = attr->task_fd_query.fd; 2252 const struct perf_event *event; 2253 struct files_struct *files; 2254 struct task_struct *task; 2255 struct file *file; 2256 int err; 2257 2258 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 2259 return -EINVAL; 2260 2261 if (!capable(CAP_SYS_ADMIN)) 2262 return -EPERM; 2263 2264 if (attr->task_fd_query.flags != 0) 2265 return -EINVAL; 2266 2267 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 2268 if (!task) 2269 return -ENOENT; 2270 2271 files = get_files_struct(task); 2272 put_task_struct(task); 2273 if (!files) 2274 return -ENOENT; 2275 2276 err = 0; 2277 spin_lock(&files->file_lock); 2278 file = fcheck_files(files, fd); 2279 if (!file) 2280 err = -EBADF; 2281 else 2282 get_file(file); 2283 spin_unlock(&files->file_lock); 2284 put_files_struct(files); 2285 2286 if (err) 2287 goto out; 2288 2289 if (file->f_op == &bpf_raw_tp_fops) { 2290 struct bpf_raw_tracepoint *raw_tp = file->private_data; 2291 struct bpf_raw_event_map *btp = raw_tp->btp; 2292 2293 err = bpf_task_fd_query_copy(attr, uattr, 2294 raw_tp->prog->aux->id, 2295 BPF_FD_TYPE_RAW_TRACEPOINT, 2296 btp->tp->name, 0, 0); 2297 goto put_file; 2298 } 2299 2300 event = perf_get_event(file); 2301 if (!IS_ERR(event)) { 2302 u64 probe_offset, probe_addr; 2303 u32 prog_id, fd_type; 2304 const char *buf; 2305 2306 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 2307 &buf, &probe_offset, 2308 &probe_addr); 2309 if (!err) 2310 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 2311 fd_type, buf, 2312 probe_offset, 2313 probe_addr); 2314 goto put_file; 2315 } 2316 2317 err = -ENOTSUPP; 2318 put_file: 2319 fput(file); 2320 out: 2321 return err; 2322 } 2323 2324 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 2325 { 2326 union bpf_attr attr = {}; 2327 int err; 2328 2329 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 2330 return -EPERM; 2331 2332 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 2333 if (err) 2334 return err; 2335 size = min_t(u32, size, sizeof(attr)); 2336 2337 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 2338 if (copy_from_user(&attr, uattr, size) != 0) 2339 return -EFAULT; 2340 2341 err = security_bpf(cmd, &attr, size); 2342 if (err < 0) 2343 return err; 2344 2345 switch (cmd) { 2346 case BPF_MAP_CREATE: 2347 err = map_create(&attr); 2348 break; 2349 case BPF_MAP_LOOKUP_ELEM: 2350 err = map_lookup_elem(&attr); 2351 break; 2352 case BPF_MAP_UPDATE_ELEM: 2353 err = map_update_elem(&attr); 2354 break; 2355 case BPF_MAP_DELETE_ELEM: 2356 err = map_delete_elem(&attr); 2357 break; 2358 case BPF_MAP_GET_NEXT_KEY: 2359 err = map_get_next_key(&attr); 2360 break; 2361 case BPF_PROG_LOAD: 2362 err = bpf_prog_load(&attr); 2363 break; 2364 case BPF_OBJ_PIN: 2365 err = bpf_obj_pin(&attr); 2366 break; 2367 case BPF_OBJ_GET: 2368 err = bpf_obj_get(&attr); 2369 break; 2370 #ifdef CONFIG_CGROUP_BPF 2371 case BPF_PROG_ATTACH: 2372 err = bpf_prog_attach(&attr); 2373 break; 2374 case BPF_PROG_DETACH: 2375 err = bpf_prog_detach(&attr); 2376 break; 2377 case BPF_PROG_QUERY: 2378 err = bpf_prog_query(&attr, uattr); 2379 break; 2380 #endif 2381 case BPF_PROG_TEST_RUN: 2382 err = bpf_prog_test_run(&attr, uattr); 2383 break; 2384 case BPF_PROG_GET_NEXT_ID: 2385 err = bpf_obj_get_next_id(&attr, uattr, 2386 &prog_idr, &prog_idr_lock); 2387 break; 2388 case BPF_MAP_GET_NEXT_ID: 2389 err = bpf_obj_get_next_id(&attr, uattr, 2390 &map_idr, &map_idr_lock); 2391 break; 2392 case BPF_PROG_GET_FD_BY_ID: 2393 err = bpf_prog_get_fd_by_id(&attr); 2394 break; 2395 case BPF_MAP_GET_FD_BY_ID: 2396 err = bpf_map_get_fd_by_id(&attr); 2397 break; 2398 case BPF_OBJ_GET_INFO_BY_FD: 2399 err = bpf_obj_get_info_by_fd(&attr, uattr); 2400 break; 2401 case BPF_RAW_TRACEPOINT_OPEN: 2402 err = bpf_raw_tracepoint_open(&attr); 2403 break; 2404 case BPF_BTF_LOAD: 2405 err = bpf_btf_load(&attr); 2406 break; 2407 case BPF_BTF_GET_FD_BY_ID: 2408 err = bpf_btf_get_fd_by_id(&attr); 2409 break; 2410 case BPF_TASK_FD_QUERY: 2411 err = bpf_task_fd_query(&attr, uattr); 2412 break; 2413 default: 2414 err = -EINVAL; 2415 break; 2416 } 2417 2418 return err; 2419 } 2420