1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf-cgroup.h> 6 #include <linux/bpf_trace.h> 7 #include <linux/bpf_lirc.h> 8 #include <linux/bpf_verifier.h> 9 #include <linux/btf.h> 10 #include <linux/syscalls.h> 11 #include <linux/slab.h> 12 #include <linux/sched/signal.h> 13 #include <linux/vmalloc.h> 14 #include <linux/mmzone.h> 15 #include <linux/anon_inodes.h> 16 #include <linux/fdtable.h> 17 #include <linux/file.h> 18 #include <linux/fs.h> 19 #include <linux/license.h> 20 #include <linux/filter.h> 21 #include <linux/kernel.h> 22 #include <linux/idr.h> 23 #include <linux/cred.h> 24 #include <linux/timekeeping.h> 25 #include <linux/ctype.h> 26 #include <linux/nospec.h> 27 #include <linux/audit.h> 28 #include <uapi/linux/btf.h> 29 #include <linux/pgtable.h> 30 #include <linux/bpf_lsm.h> 31 #include <linux/poll.h> 32 #include <linux/bpf-netns.h> 33 #include <linux/rcupdate_trace.h> 34 #include <linux/memcontrol.h> 35 36 #define IS_FD_ARRAY(map) ((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_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 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_PROG_ARRAY(map) || \ 42 IS_FD_HASH(map)) 43 44 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 45 46 DEFINE_PER_CPU(int, bpf_prog_active); 47 static DEFINE_IDR(prog_idr); 48 static DEFINE_SPINLOCK(prog_idr_lock); 49 static DEFINE_IDR(map_idr); 50 static DEFINE_SPINLOCK(map_idr_lock); 51 static DEFINE_IDR(link_idr); 52 static DEFINE_SPINLOCK(link_idr_lock); 53 54 int sysctl_unprivileged_bpf_disabled __read_mostly = 55 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 56 57 static const struct bpf_map_ops * const bpf_map_types[] = { 58 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 59 #define BPF_MAP_TYPE(_id, _ops) \ 60 [_id] = &_ops, 61 #define BPF_LINK_TYPE(_id, _name) 62 #include <linux/bpf_types.h> 63 #undef BPF_PROG_TYPE 64 #undef BPF_MAP_TYPE 65 #undef BPF_LINK_TYPE 66 }; 67 68 /* 69 * If we're handed a bigger struct than we know of, ensure all the unknown bits 70 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 71 * we don't know about yet. 72 * 73 * There is a ToCToU between this function call and the following 74 * copy_from_user() call. However, this is not a concern since this function is 75 * meant to be a future-proofing of bits. 76 */ 77 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 78 size_t expected_size, 79 size_t actual_size) 80 { 81 int res; 82 83 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 84 return -E2BIG; 85 86 if (actual_size <= expected_size) 87 return 0; 88 89 if (uaddr.is_kernel) 90 res = memchr_inv(uaddr.kernel + expected_size, 0, 91 actual_size - expected_size) == NULL; 92 else 93 res = check_zeroed_user(uaddr.user + expected_size, 94 actual_size - expected_size); 95 if (res < 0) 96 return res; 97 return res ? 0 : -E2BIG; 98 } 99 100 const struct bpf_map_ops bpf_map_offload_ops = { 101 .map_meta_equal = bpf_map_meta_equal, 102 .map_alloc = bpf_map_offload_map_alloc, 103 .map_free = bpf_map_offload_map_free, 104 .map_check_btf = map_check_no_btf, 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 static void bpf_map_write_active_inc(struct bpf_map *map) 137 { 138 atomic64_inc(&map->writecnt); 139 } 140 141 static void bpf_map_write_active_dec(struct bpf_map *map) 142 { 143 atomic64_dec(&map->writecnt); 144 } 145 146 bool bpf_map_write_active(const struct bpf_map *map) 147 { 148 return atomic64_read(&map->writecnt) != 0; 149 } 150 151 static u32 bpf_map_value_size(const struct bpf_map *map) 152 { 153 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 154 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 155 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 156 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 157 return round_up(map->value_size, 8) * num_possible_cpus(); 158 else if (IS_FD_MAP(map)) 159 return sizeof(u32); 160 else 161 return map->value_size; 162 } 163 164 static void maybe_wait_bpf_programs(struct bpf_map *map) 165 { 166 /* Wait for any running BPF programs to complete so that 167 * userspace, when we return to it, knows that all programs 168 * that could be running use the new map value. 169 */ 170 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 171 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 172 synchronize_rcu(); 173 } 174 175 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 176 void *value, __u64 flags) 177 { 178 int err; 179 180 /* Need to create a kthread, thus must support schedule */ 181 if (bpf_map_is_dev_bound(map)) { 182 return bpf_map_offload_update_elem(map, key, value, flags); 183 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 184 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 185 return map->ops->map_update_elem(map, key, value, flags); 186 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 187 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 188 return sock_map_update_elem_sys(map, key, value, flags); 189 } else if (IS_FD_PROG_ARRAY(map)) { 190 return bpf_fd_array_map_update_elem(map, f.file, key, value, 191 flags); 192 } 193 194 bpf_disable_instrumentation(); 195 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 196 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 197 err = bpf_percpu_hash_update(map, key, value, flags); 198 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 199 err = bpf_percpu_array_update(map, key, value, flags); 200 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 201 err = bpf_percpu_cgroup_storage_update(map, key, value, 202 flags); 203 } else if (IS_FD_ARRAY(map)) { 204 rcu_read_lock(); 205 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 206 flags); 207 rcu_read_unlock(); 208 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 209 rcu_read_lock(); 210 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 211 flags); 212 rcu_read_unlock(); 213 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 214 /* rcu_read_lock() is not needed */ 215 err = bpf_fd_reuseport_array_update_elem(map, key, value, 216 flags); 217 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 218 map->map_type == BPF_MAP_TYPE_STACK || 219 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 220 err = map->ops->map_push_elem(map, value, flags); 221 } else { 222 rcu_read_lock(); 223 err = map->ops->map_update_elem(map, key, value, flags); 224 rcu_read_unlock(); 225 } 226 bpf_enable_instrumentation(); 227 maybe_wait_bpf_programs(map); 228 229 return err; 230 } 231 232 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 233 __u64 flags) 234 { 235 void *ptr; 236 int err; 237 238 if (bpf_map_is_dev_bound(map)) 239 return bpf_map_offload_lookup_elem(map, key, value); 240 241 bpf_disable_instrumentation(); 242 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 243 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 244 err = bpf_percpu_hash_copy(map, key, value); 245 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 246 err = bpf_percpu_array_copy(map, key, value); 247 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 248 err = bpf_percpu_cgroup_storage_copy(map, key, value); 249 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 250 err = bpf_stackmap_copy(map, key, value); 251 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 252 err = bpf_fd_array_map_lookup_elem(map, key, value); 253 } else if (IS_FD_HASH(map)) { 254 err = bpf_fd_htab_map_lookup_elem(map, key, value); 255 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 256 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 257 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 258 map->map_type == BPF_MAP_TYPE_STACK || 259 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 260 err = map->ops->map_peek_elem(map, value); 261 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 262 /* struct_ops map requires directly updating "value" */ 263 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 264 } else { 265 rcu_read_lock(); 266 if (map->ops->map_lookup_elem_sys_only) 267 ptr = map->ops->map_lookup_elem_sys_only(map, key); 268 else 269 ptr = map->ops->map_lookup_elem(map, key); 270 if (IS_ERR(ptr)) { 271 err = PTR_ERR(ptr); 272 } else if (!ptr) { 273 err = -ENOENT; 274 } else { 275 err = 0; 276 if (flags & BPF_F_LOCK) 277 /* lock 'ptr' and copy everything but lock */ 278 copy_map_value_locked(map, value, ptr, true); 279 else 280 copy_map_value(map, value, ptr); 281 /* mask lock and timer, since value wasn't zero inited */ 282 check_and_init_map_value(map, value); 283 } 284 rcu_read_unlock(); 285 } 286 287 bpf_enable_instrumentation(); 288 maybe_wait_bpf_programs(map); 289 290 return err; 291 } 292 293 /* Please, do not use this function outside from the map creation path 294 * (e.g. in map update path) without taking care of setting the active 295 * memory cgroup (see at bpf_map_kmalloc_node() for example). 296 */ 297 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 298 { 299 /* We really just want to fail instead of triggering OOM killer 300 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 301 * which is used for lower order allocation requests. 302 * 303 * It has been observed that higher order allocation requests done by 304 * vmalloc with __GFP_NORETRY being set might fail due to not trying 305 * to reclaim memory from the page cache, thus we set 306 * __GFP_RETRY_MAYFAIL to avoid such situations. 307 */ 308 309 const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT; 310 unsigned int flags = 0; 311 unsigned long align = 1; 312 void *area; 313 314 if (size >= SIZE_MAX) 315 return NULL; 316 317 /* kmalloc()'ed memory can't be mmap()'ed */ 318 if (mmapable) { 319 BUG_ON(!PAGE_ALIGNED(size)); 320 align = SHMLBA; 321 flags = VM_USERMAP; 322 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 323 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 324 numa_node); 325 if (area != NULL) 326 return area; 327 } 328 329 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 330 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 331 flags, numa_node, __builtin_return_address(0)); 332 } 333 334 void *bpf_map_area_alloc(u64 size, int numa_node) 335 { 336 return __bpf_map_area_alloc(size, numa_node, false); 337 } 338 339 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 340 { 341 return __bpf_map_area_alloc(size, numa_node, true); 342 } 343 344 void bpf_map_area_free(void *area) 345 { 346 kvfree(area); 347 } 348 349 static u32 bpf_map_flags_retain_permanent(u32 flags) 350 { 351 /* Some map creation flags are not tied to the map object but 352 * rather to the map fd instead, so they have no meaning upon 353 * map object inspection since multiple file descriptors with 354 * different (access) properties can exist here. Thus, given 355 * this has zero meaning for the map itself, lets clear these 356 * from here. 357 */ 358 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 359 } 360 361 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 362 { 363 map->map_type = attr->map_type; 364 map->key_size = attr->key_size; 365 map->value_size = attr->value_size; 366 map->max_entries = attr->max_entries; 367 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 368 map->numa_node = bpf_map_attr_numa_node(attr); 369 map->map_extra = attr->map_extra; 370 } 371 372 static int bpf_map_alloc_id(struct bpf_map *map) 373 { 374 int id; 375 376 idr_preload(GFP_KERNEL); 377 spin_lock_bh(&map_idr_lock); 378 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 379 if (id > 0) 380 map->id = id; 381 spin_unlock_bh(&map_idr_lock); 382 idr_preload_end(); 383 384 if (WARN_ON_ONCE(!id)) 385 return -ENOSPC; 386 387 return id > 0 ? 0 : id; 388 } 389 390 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 391 { 392 unsigned long flags; 393 394 /* Offloaded maps are removed from the IDR store when their device 395 * disappears - even if someone holds an fd to them they are unusable, 396 * the memory is gone, all ops will fail; they are simply waiting for 397 * refcnt to drop to be freed. 398 */ 399 if (!map->id) 400 return; 401 402 if (do_idr_lock) 403 spin_lock_irqsave(&map_idr_lock, flags); 404 else 405 __acquire(&map_idr_lock); 406 407 idr_remove(&map_idr, map->id); 408 map->id = 0; 409 410 if (do_idr_lock) 411 spin_unlock_irqrestore(&map_idr_lock, flags); 412 else 413 __release(&map_idr_lock); 414 } 415 416 #ifdef CONFIG_MEMCG_KMEM 417 static void bpf_map_save_memcg(struct bpf_map *map) 418 { 419 map->memcg = get_mem_cgroup_from_mm(current->mm); 420 } 421 422 static void bpf_map_release_memcg(struct bpf_map *map) 423 { 424 mem_cgroup_put(map->memcg); 425 } 426 427 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 428 int node) 429 { 430 struct mem_cgroup *old_memcg; 431 void *ptr; 432 433 old_memcg = set_active_memcg(map->memcg); 434 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 435 set_active_memcg(old_memcg); 436 437 return ptr; 438 } 439 440 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 441 { 442 struct mem_cgroup *old_memcg; 443 void *ptr; 444 445 old_memcg = set_active_memcg(map->memcg); 446 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 447 set_active_memcg(old_memcg); 448 449 return ptr; 450 } 451 452 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 453 size_t align, gfp_t flags) 454 { 455 struct mem_cgroup *old_memcg; 456 void __percpu *ptr; 457 458 old_memcg = set_active_memcg(map->memcg); 459 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 460 set_active_memcg(old_memcg); 461 462 return ptr; 463 } 464 465 #else 466 static void bpf_map_save_memcg(struct bpf_map *map) 467 { 468 } 469 470 static void bpf_map_release_memcg(struct bpf_map *map) 471 { 472 } 473 #endif 474 475 /* called from workqueue */ 476 static void bpf_map_free_deferred(struct work_struct *work) 477 { 478 struct bpf_map *map = container_of(work, struct bpf_map, work); 479 480 security_bpf_map_free(map); 481 bpf_map_release_memcg(map); 482 /* implementation dependent freeing */ 483 map->ops->map_free(map); 484 } 485 486 static void bpf_map_put_uref(struct bpf_map *map) 487 { 488 if (atomic64_dec_and_test(&map->usercnt)) { 489 if (map->ops->map_release_uref) 490 map->ops->map_release_uref(map); 491 } 492 } 493 494 /* decrement map refcnt and schedule it for freeing via workqueue 495 * (unrelying map implementation ops->map_free() might sleep) 496 */ 497 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 498 { 499 if (atomic64_dec_and_test(&map->refcnt)) { 500 /* bpf_map_free_id() must be called first */ 501 bpf_map_free_id(map, do_idr_lock); 502 btf_put(map->btf); 503 INIT_WORK(&map->work, bpf_map_free_deferred); 504 schedule_work(&map->work); 505 } 506 } 507 508 void bpf_map_put(struct bpf_map *map) 509 { 510 __bpf_map_put(map, true); 511 } 512 EXPORT_SYMBOL_GPL(bpf_map_put); 513 514 void bpf_map_put_with_uref(struct bpf_map *map) 515 { 516 bpf_map_put_uref(map); 517 bpf_map_put(map); 518 } 519 520 static int bpf_map_release(struct inode *inode, struct file *filp) 521 { 522 struct bpf_map *map = filp->private_data; 523 524 if (map->ops->map_release) 525 map->ops->map_release(map, filp); 526 527 bpf_map_put_with_uref(map); 528 return 0; 529 } 530 531 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 532 { 533 fmode_t mode = f.file->f_mode; 534 535 /* Our file permissions may have been overridden by global 536 * map permissions facing syscall side. 537 */ 538 if (READ_ONCE(map->frozen)) 539 mode &= ~FMODE_CAN_WRITE; 540 return mode; 541 } 542 543 #ifdef CONFIG_PROC_FS 544 /* Provides an approximation of the map's memory footprint. 545 * Used only to provide a backward compatibility and display 546 * a reasonable "memlock" info. 547 */ 548 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map) 549 { 550 unsigned long size; 551 552 size = round_up(map->key_size + bpf_map_value_size(map), 8); 553 554 return round_up(map->max_entries * size, PAGE_SIZE); 555 } 556 557 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 558 { 559 const struct bpf_map *map = filp->private_data; 560 const struct bpf_array *array; 561 u32 type = 0, jited = 0; 562 563 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 564 array = container_of(map, struct bpf_array, map); 565 spin_lock(&array->aux->owner.lock); 566 type = array->aux->owner.type; 567 jited = array->aux->owner.jited; 568 spin_unlock(&array->aux->owner.lock); 569 } 570 571 seq_printf(m, 572 "map_type:\t%u\n" 573 "key_size:\t%u\n" 574 "value_size:\t%u\n" 575 "max_entries:\t%u\n" 576 "map_flags:\t%#x\n" 577 "map_extra:\t%#llx\n" 578 "memlock:\t%lu\n" 579 "map_id:\t%u\n" 580 "frozen:\t%u\n", 581 map->map_type, 582 map->key_size, 583 map->value_size, 584 map->max_entries, 585 map->map_flags, 586 (unsigned long long)map->map_extra, 587 bpf_map_memory_footprint(map), 588 map->id, 589 READ_ONCE(map->frozen)); 590 if (type) { 591 seq_printf(m, "owner_prog_type:\t%u\n", type); 592 seq_printf(m, "owner_jited:\t%u\n", jited); 593 } 594 } 595 #endif 596 597 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 598 loff_t *ppos) 599 { 600 /* We need this handler such that alloc_file() enables 601 * f_mode with FMODE_CAN_READ. 602 */ 603 return -EINVAL; 604 } 605 606 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 607 size_t siz, loff_t *ppos) 608 { 609 /* We need this handler such that alloc_file() enables 610 * f_mode with FMODE_CAN_WRITE. 611 */ 612 return -EINVAL; 613 } 614 615 /* called for any extra memory-mapped regions (except initial) */ 616 static void bpf_map_mmap_open(struct vm_area_struct *vma) 617 { 618 struct bpf_map *map = vma->vm_file->private_data; 619 620 if (vma->vm_flags & VM_MAYWRITE) 621 bpf_map_write_active_inc(map); 622 } 623 624 /* called for all unmapped memory region (including initial) */ 625 static void bpf_map_mmap_close(struct vm_area_struct *vma) 626 { 627 struct bpf_map *map = vma->vm_file->private_data; 628 629 if (vma->vm_flags & VM_MAYWRITE) 630 bpf_map_write_active_dec(map); 631 } 632 633 static const struct vm_operations_struct bpf_map_default_vmops = { 634 .open = bpf_map_mmap_open, 635 .close = bpf_map_mmap_close, 636 }; 637 638 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 639 { 640 struct bpf_map *map = filp->private_data; 641 int err; 642 643 if (!map->ops->map_mmap || map_value_has_spin_lock(map) || 644 map_value_has_timer(map)) 645 return -ENOTSUPP; 646 647 if (!(vma->vm_flags & VM_SHARED)) 648 return -EINVAL; 649 650 mutex_lock(&map->freeze_mutex); 651 652 if (vma->vm_flags & VM_WRITE) { 653 if (map->frozen) { 654 err = -EPERM; 655 goto out; 656 } 657 /* map is meant to be read-only, so do not allow mapping as 658 * writable, because it's possible to leak a writable page 659 * reference and allows user-space to still modify it after 660 * freezing, while verifier will assume contents do not change 661 */ 662 if (map->map_flags & BPF_F_RDONLY_PROG) { 663 err = -EACCES; 664 goto out; 665 } 666 } 667 668 /* set default open/close callbacks */ 669 vma->vm_ops = &bpf_map_default_vmops; 670 vma->vm_private_data = map; 671 vma->vm_flags &= ~VM_MAYEXEC; 672 if (!(vma->vm_flags & VM_WRITE)) 673 /* disallow re-mapping with PROT_WRITE */ 674 vma->vm_flags &= ~VM_MAYWRITE; 675 676 err = map->ops->map_mmap(map, vma); 677 if (err) 678 goto out; 679 680 if (vma->vm_flags & VM_MAYWRITE) 681 bpf_map_write_active_inc(map); 682 out: 683 mutex_unlock(&map->freeze_mutex); 684 return err; 685 } 686 687 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 688 { 689 struct bpf_map *map = filp->private_data; 690 691 if (map->ops->map_poll) 692 return map->ops->map_poll(map, filp, pts); 693 694 return EPOLLERR; 695 } 696 697 const struct file_operations bpf_map_fops = { 698 #ifdef CONFIG_PROC_FS 699 .show_fdinfo = bpf_map_show_fdinfo, 700 #endif 701 .release = bpf_map_release, 702 .read = bpf_dummy_read, 703 .write = bpf_dummy_write, 704 .mmap = bpf_map_mmap, 705 .poll = bpf_map_poll, 706 }; 707 708 int bpf_map_new_fd(struct bpf_map *map, int flags) 709 { 710 int ret; 711 712 ret = security_bpf_map(map, OPEN_FMODE(flags)); 713 if (ret < 0) 714 return ret; 715 716 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 717 flags | O_CLOEXEC); 718 } 719 720 int bpf_get_file_flag(int flags) 721 { 722 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 723 return -EINVAL; 724 if (flags & BPF_F_RDONLY) 725 return O_RDONLY; 726 if (flags & BPF_F_WRONLY) 727 return O_WRONLY; 728 return O_RDWR; 729 } 730 731 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 732 #define CHECK_ATTR(CMD) \ 733 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 734 sizeof(attr->CMD##_LAST_FIELD), 0, \ 735 sizeof(*attr) - \ 736 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 737 sizeof(attr->CMD##_LAST_FIELD)) != NULL 738 739 /* dst and src must have at least "size" number of bytes. 740 * Return strlen on success and < 0 on error. 741 */ 742 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 743 { 744 const char *end = src + size; 745 const char *orig_src = src; 746 747 memset(dst, 0, size); 748 /* Copy all isalnum(), '_' and '.' chars. */ 749 while (src < end && *src) { 750 if (!isalnum(*src) && 751 *src != '_' && *src != '.') 752 return -EINVAL; 753 *dst++ = *src++; 754 } 755 756 /* No '\0' found in "size" number of bytes */ 757 if (src == end) 758 return -EINVAL; 759 760 return src - orig_src; 761 } 762 763 int map_check_no_btf(const struct bpf_map *map, 764 const struct btf *btf, 765 const struct btf_type *key_type, 766 const struct btf_type *value_type) 767 { 768 return -ENOTSUPP; 769 } 770 771 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 772 u32 btf_key_id, u32 btf_value_id) 773 { 774 const struct btf_type *key_type, *value_type; 775 u32 key_size, value_size; 776 int ret = 0; 777 778 /* Some maps allow key to be unspecified. */ 779 if (btf_key_id) { 780 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 781 if (!key_type || key_size != map->key_size) 782 return -EINVAL; 783 } else { 784 key_type = btf_type_by_id(btf, 0); 785 if (!map->ops->map_check_btf) 786 return -EINVAL; 787 } 788 789 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 790 if (!value_type || value_size != map->value_size) 791 return -EINVAL; 792 793 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 794 795 if (map_value_has_spin_lock(map)) { 796 if (map->map_flags & BPF_F_RDONLY_PROG) 797 return -EACCES; 798 if (map->map_type != BPF_MAP_TYPE_HASH && 799 map->map_type != BPF_MAP_TYPE_ARRAY && 800 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 801 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 802 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 803 map->map_type != BPF_MAP_TYPE_TASK_STORAGE) 804 return -ENOTSUPP; 805 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 806 map->value_size) { 807 WARN_ONCE(1, 808 "verifier bug spin_lock_off %d value_size %d\n", 809 map->spin_lock_off, map->value_size); 810 return -EFAULT; 811 } 812 } 813 814 map->timer_off = btf_find_timer(btf, value_type); 815 if (map_value_has_timer(map)) { 816 if (map->map_flags & BPF_F_RDONLY_PROG) 817 return -EACCES; 818 if (map->map_type != BPF_MAP_TYPE_HASH && 819 map->map_type != BPF_MAP_TYPE_LRU_HASH && 820 map->map_type != BPF_MAP_TYPE_ARRAY) 821 return -EOPNOTSUPP; 822 } 823 824 if (map->ops->map_check_btf) 825 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 826 827 return ret; 828 } 829 830 #define BPF_MAP_CREATE_LAST_FIELD map_extra 831 /* called via syscall */ 832 static int map_create(union bpf_attr *attr) 833 { 834 int numa_node = bpf_map_attr_numa_node(attr); 835 struct bpf_map *map; 836 int f_flags; 837 int err; 838 839 err = CHECK_ATTR(BPF_MAP_CREATE); 840 if (err) 841 return -EINVAL; 842 843 if (attr->btf_vmlinux_value_type_id) { 844 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 845 attr->btf_key_type_id || attr->btf_value_type_id) 846 return -EINVAL; 847 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 848 return -EINVAL; 849 } 850 851 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 852 attr->map_extra != 0) 853 return -EINVAL; 854 855 f_flags = bpf_get_file_flag(attr->map_flags); 856 if (f_flags < 0) 857 return f_flags; 858 859 if (numa_node != NUMA_NO_NODE && 860 ((unsigned int)numa_node >= nr_node_ids || 861 !node_online(numa_node))) 862 return -EINVAL; 863 864 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 865 map = find_and_alloc_map(attr); 866 if (IS_ERR(map)) 867 return PTR_ERR(map); 868 869 err = bpf_obj_name_cpy(map->name, attr->map_name, 870 sizeof(attr->map_name)); 871 if (err < 0) 872 goto free_map; 873 874 atomic64_set(&map->refcnt, 1); 875 atomic64_set(&map->usercnt, 1); 876 mutex_init(&map->freeze_mutex); 877 878 map->spin_lock_off = -EINVAL; 879 map->timer_off = -EINVAL; 880 if (attr->btf_key_type_id || attr->btf_value_type_id || 881 /* Even the map's value is a kernel's struct, 882 * the bpf_prog.o must have BTF to begin with 883 * to figure out the corresponding kernel's 884 * counter part. Thus, attr->btf_fd has 885 * to be valid also. 886 */ 887 attr->btf_vmlinux_value_type_id) { 888 struct btf *btf; 889 890 btf = btf_get_by_fd(attr->btf_fd); 891 if (IS_ERR(btf)) { 892 err = PTR_ERR(btf); 893 goto free_map; 894 } 895 if (btf_is_kernel(btf)) { 896 btf_put(btf); 897 err = -EACCES; 898 goto free_map; 899 } 900 map->btf = btf; 901 902 if (attr->btf_value_type_id) { 903 err = map_check_btf(map, btf, attr->btf_key_type_id, 904 attr->btf_value_type_id); 905 if (err) 906 goto free_map; 907 } 908 909 map->btf_key_type_id = attr->btf_key_type_id; 910 map->btf_value_type_id = attr->btf_value_type_id; 911 map->btf_vmlinux_value_type_id = 912 attr->btf_vmlinux_value_type_id; 913 } 914 915 err = security_bpf_map_alloc(map); 916 if (err) 917 goto free_map; 918 919 err = bpf_map_alloc_id(map); 920 if (err) 921 goto free_map_sec; 922 923 bpf_map_save_memcg(map); 924 925 err = bpf_map_new_fd(map, f_flags); 926 if (err < 0) { 927 /* failed to allocate fd. 928 * bpf_map_put_with_uref() is needed because the above 929 * bpf_map_alloc_id() has published the map 930 * to the userspace and the userspace may 931 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 932 */ 933 bpf_map_put_with_uref(map); 934 return err; 935 } 936 937 return err; 938 939 free_map_sec: 940 security_bpf_map_free(map); 941 free_map: 942 btf_put(map->btf); 943 map->ops->map_free(map); 944 return err; 945 } 946 947 /* if error is returned, fd is released. 948 * On success caller should complete fd access with matching fdput() 949 */ 950 struct bpf_map *__bpf_map_get(struct fd f) 951 { 952 if (!f.file) 953 return ERR_PTR(-EBADF); 954 if (f.file->f_op != &bpf_map_fops) { 955 fdput(f); 956 return ERR_PTR(-EINVAL); 957 } 958 959 return f.file->private_data; 960 } 961 962 void bpf_map_inc(struct bpf_map *map) 963 { 964 atomic64_inc(&map->refcnt); 965 } 966 EXPORT_SYMBOL_GPL(bpf_map_inc); 967 968 void bpf_map_inc_with_uref(struct bpf_map *map) 969 { 970 atomic64_inc(&map->refcnt); 971 atomic64_inc(&map->usercnt); 972 } 973 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 974 975 struct bpf_map *bpf_map_get(u32 ufd) 976 { 977 struct fd f = fdget(ufd); 978 struct bpf_map *map; 979 980 map = __bpf_map_get(f); 981 if (IS_ERR(map)) 982 return map; 983 984 bpf_map_inc(map); 985 fdput(f); 986 987 return map; 988 } 989 990 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 991 { 992 struct fd f = fdget(ufd); 993 struct bpf_map *map; 994 995 map = __bpf_map_get(f); 996 if (IS_ERR(map)) 997 return map; 998 999 bpf_map_inc_with_uref(map); 1000 fdput(f); 1001 1002 return map; 1003 } 1004 1005 /* map_idr_lock should have been held */ 1006 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1007 { 1008 int refold; 1009 1010 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1011 if (!refold) 1012 return ERR_PTR(-ENOENT); 1013 if (uref) 1014 atomic64_inc(&map->usercnt); 1015 1016 return map; 1017 } 1018 1019 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1020 { 1021 spin_lock_bh(&map_idr_lock); 1022 map = __bpf_map_inc_not_zero(map, false); 1023 spin_unlock_bh(&map_idr_lock); 1024 1025 return map; 1026 } 1027 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1028 1029 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1030 { 1031 return -ENOTSUPP; 1032 } 1033 1034 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1035 { 1036 if (key_size) 1037 return vmemdup_user(ukey, key_size); 1038 1039 if (ukey) 1040 return ERR_PTR(-EINVAL); 1041 1042 return NULL; 1043 } 1044 1045 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1046 { 1047 if (key_size) 1048 return kvmemdup_bpfptr(ukey, key_size); 1049 1050 if (!bpfptr_is_null(ukey)) 1051 return ERR_PTR(-EINVAL); 1052 1053 return NULL; 1054 } 1055 1056 /* last field in 'union bpf_attr' used by this command */ 1057 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1058 1059 static int map_lookup_elem(union bpf_attr *attr) 1060 { 1061 void __user *ukey = u64_to_user_ptr(attr->key); 1062 void __user *uvalue = u64_to_user_ptr(attr->value); 1063 int ufd = attr->map_fd; 1064 struct bpf_map *map; 1065 void *key, *value; 1066 u32 value_size; 1067 struct fd f; 1068 int err; 1069 1070 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1071 return -EINVAL; 1072 1073 if (attr->flags & ~BPF_F_LOCK) 1074 return -EINVAL; 1075 1076 f = fdget(ufd); 1077 map = __bpf_map_get(f); 1078 if (IS_ERR(map)) 1079 return PTR_ERR(map); 1080 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1081 err = -EPERM; 1082 goto err_put; 1083 } 1084 1085 if ((attr->flags & BPF_F_LOCK) && 1086 !map_value_has_spin_lock(map)) { 1087 err = -EINVAL; 1088 goto err_put; 1089 } 1090 1091 key = __bpf_copy_key(ukey, map->key_size); 1092 if (IS_ERR(key)) { 1093 err = PTR_ERR(key); 1094 goto err_put; 1095 } 1096 1097 value_size = bpf_map_value_size(map); 1098 1099 err = -ENOMEM; 1100 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1101 if (!value) 1102 goto free_key; 1103 1104 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1105 if (copy_from_user(value, uvalue, value_size)) 1106 err = -EFAULT; 1107 else 1108 err = bpf_map_copy_value(map, key, value, attr->flags); 1109 goto free_value; 1110 } 1111 1112 err = bpf_map_copy_value(map, key, value, attr->flags); 1113 if (err) 1114 goto free_value; 1115 1116 err = -EFAULT; 1117 if (copy_to_user(uvalue, value, value_size) != 0) 1118 goto free_value; 1119 1120 err = 0; 1121 1122 free_value: 1123 kvfree(value); 1124 free_key: 1125 kvfree(key); 1126 err_put: 1127 fdput(f); 1128 return err; 1129 } 1130 1131 1132 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1133 1134 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1135 { 1136 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1137 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1138 int ufd = attr->map_fd; 1139 struct bpf_map *map; 1140 void *key, *value; 1141 u32 value_size; 1142 struct fd f; 1143 int err; 1144 1145 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1146 return -EINVAL; 1147 1148 f = fdget(ufd); 1149 map = __bpf_map_get(f); 1150 if (IS_ERR(map)) 1151 return PTR_ERR(map); 1152 bpf_map_write_active_inc(map); 1153 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1154 err = -EPERM; 1155 goto err_put; 1156 } 1157 1158 if ((attr->flags & BPF_F_LOCK) && 1159 !map_value_has_spin_lock(map)) { 1160 err = -EINVAL; 1161 goto err_put; 1162 } 1163 1164 key = ___bpf_copy_key(ukey, map->key_size); 1165 if (IS_ERR(key)) { 1166 err = PTR_ERR(key); 1167 goto err_put; 1168 } 1169 1170 value_size = bpf_map_value_size(map); 1171 1172 err = -ENOMEM; 1173 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1174 if (!value) 1175 goto free_key; 1176 1177 err = -EFAULT; 1178 if (copy_from_bpfptr(value, uvalue, value_size) != 0) 1179 goto free_value; 1180 1181 err = bpf_map_update_value(map, f, key, value, attr->flags); 1182 1183 free_value: 1184 kvfree(value); 1185 free_key: 1186 kvfree(key); 1187 err_put: 1188 bpf_map_write_active_dec(map); 1189 fdput(f); 1190 return err; 1191 } 1192 1193 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1194 1195 static int map_delete_elem(union bpf_attr *attr) 1196 { 1197 void __user *ukey = u64_to_user_ptr(attr->key); 1198 int ufd = attr->map_fd; 1199 struct bpf_map *map; 1200 struct fd f; 1201 void *key; 1202 int err; 1203 1204 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1205 return -EINVAL; 1206 1207 f = fdget(ufd); 1208 map = __bpf_map_get(f); 1209 if (IS_ERR(map)) 1210 return PTR_ERR(map); 1211 bpf_map_write_active_inc(map); 1212 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1213 err = -EPERM; 1214 goto err_put; 1215 } 1216 1217 key = __bpf_copy_key(ukey, map->key_size); 1218 if (IS_ERR(key)) { 1219 err = PTR_ERR(key); 1220 goto err_put; 1221 } 1222 1223 if (bpf_map_is_dev_bound(map)) { 1224 err = bpf_map_offload_delete_elem(map, key); 1225 goto out; 1226 } else if (IS_FD_PROG_ARRAY(map) || 1227 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1228 /* These maps require sleepable context */ 1229 err = map->ops->map_delete_elem(map, key); 1230 goto out; 1231 } 1232 1233 bpf_disable_instrumentation(); 1234 rcu_read_lock(); 1235 err = map->ops->map_delete_elem(map, key); 1236 rcu_read_unlock(); 1237 bpf_enable_instrumentation(); 1238 maybe_wait_bpf_programs(map); 1239 out: 1240 kvfree(key); 1241 err_put: 1242 bpf_map_write_active_dec(map); 1243 fdput(f); 1244 return err; 1245 } 1246 1247 /* last field in 'union bpf_attr' used by this command */ 1248 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1249 1250 static int map_get_next_key(union bpf_attr *attr) 1251 { 1252 void __user *ukey = u64_to_user_ptr(attr->key); 1253 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1254 int ufd = attr->map_fd; 1255 struct bpf_map *map; 1256 void *key, *next_key; 1257 struct fd f; 1258 int err; 1259 1260 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1261 return -EINVAL; 1262 1263 f = fdget(ufd); 1264 map = __bpf_map_get(f); 1265 if (IS_ERR(map)) 1266 return PTR_ERR(map); 1267 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1268 err = -EPERM; 1269 goto err_put; 1270 } 1271 1272 if (ukey) { 1273 key = __bpf_copy_key(ukey, map->key_size); 1274 if (IS_ERR(key)) { 1275 err = PTR_ERR(key); 1276 goto err_put; 1277 } 1278 } else { 1279 key = NULL; 1280 } 1281 1282 err = -ENOMEM; 1283 next_key = kvmalloc(map->key_size, GFP_USER); 1284 if (!next_key) 1285 goto free_key; 1286 1287 if (bpf_map_is_dev_bound(map)) { 1288 err = bpf_map_offload_get_next_key(map, key, next_key); 1289 goto out; 1290 } 1291 1292 rcu_read_lock(); 1293 err = map->ops->map_get_next_key(map, key, next_key); 1294 rcu_read_unlock(); 1295 out: 1296 if (err) 1297 goto free_next_key; 1298 1299 err = -EFAULT; 1300 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1301 goto free_next_key; 1302 1303 err = 0; 1304 1305 free_next_key: 1306 kvfree(next_key); 1307 free_key: 1308 kvfree(key); 1309 err_put: 1310 fdput(f); 1311 return err; 1312 } 1313 1314 int generic_map_delete_batch(struct bpf_map *map, 1315 const union bpf_attr *attr, 1316 union bpf_attr __user *uattr) 1317 { 1318 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1319 u32 cp, max_count; 1320 int err = 0; 1321 void *key; 1322 1323 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1324 return -EINVAL; 1325 1326 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1327 !map_value_has_spin_lock(map)) { 1328 return -EINVAL; 1329 } 1330 1331 max_count = attr->batch.count; 1332 if (!max_count) 1333 return 0; 1334 1335 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1336 if (!key) 1337 return -ENOMEM; 1338 1339 for (cp = 0; cp < max_count; cp++) { 1340 err = -EFAULT; 1341 if (copy_from_user(key, keys + cp * map->key_size, 1342 map->key_size)) 1343 break; 1344 1345 if (bpf_map_is_dev_bound(map)) { 1346 err = bpf_map_offload_delete_elem(map, key); 1347 break; 1348 } 1349 1350 bpf_disable_instrumentation(); 1351 rcu_read_lock(); 1352 err = map->ops->map_delete_elem(map, key); 1353 rcu_read_unlock(); 1354 bpf_enable_instrumentation(); 1355 maybe_wait_bpf_programs(map); 1356 if (err) 1357 break; 1358 cond_resched(); 1359 } 1360 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1361 err = -EFAULT; 1362 1363 kvfree(key); 1364 return err; 1365 } 1366 1367 int generic_map_update_batch(struct bpf_map *map, 1368 const union bpf_attr *attr, 1369 union bpf_attr __user *uattr) 1370 { 1371 void __user *values = u64_to_user_ptr(attr->batch.values); 1372 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1373 u32 value_size, cp, max_count; 1374 int ufd = attr->batch.map_fd; 1375 void *key, *value; 1376 struct fd f; 1377 int err = 0; 1378 1379 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1380 return -EINVAL; 1381 1382 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1383 !map_value_has_spin_lock(map)) { 1384 return -EINVAL; 1385 } 1386 1387 value_size = bpf_map_value_size(map); 1388 1389 max_count = attr->batch.count; 1390 if (!max_count) 1391 return 0; 1392 1393 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1394 if (!key) 1395 return -ENOMEM; 1396 1397 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1398 if (!value) { 1399 kvfree(key); 1400 return -ENOMEM; 1401 } 1402 1403 f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */ 1404 for (cp = 0; cp < max_count; cp++) { 1405 err = -EFAULT; 1406 if (copy_from_user(key, keys + cp * map->key_size, 1407 map->key_size) || 1408 copy_from_user(value, values + cp * value_size, value_size)) 1409 break; 1410 1411 err = bpf_map_update_value(map, f, key, value, 1412 attr->batch.elem_flags); 1413 1414 if (err) 1415 break; 1416 cond_resched(); 1417 } 1418 1419 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1420 err = -EFAULT; 1421 1422 kvfree(value); 1423 kvfree(key); 1424 fdput(f); 1425 return err; 1426 } 1427 1428 #define MAP_LOOKUP_RETRIES 3 1429 1430 int generic_map_lookup_batch(struct bpf_map *map, 1431 const union bpf_attr *attr, 1432 union bpf_attr __user *uattr) 1433 { 1434 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1435 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1436 void __user *values = u64_to_user_ptr(attr->batch.values); 1437 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1438 void *buf, *buf_prevkey, *prev_key, *key, *value; 1439 int err, retry = MAP_LOOKUP_RETRIES; 1440 u32 value_size, cp, max_count; 1441 1442 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1443 return -EINVAL; 1444 1445 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1446 !map_value_has_spin_lock(map)) 1447 return -EINVAL; 1448 1449 value_size = bpf_map_value_size(map); 1450 1451 max_count = attr->batch.count; 1452 if (!max_count) 1453 return 0; 1454 1455 if (put_user(0, &uattr->batch.count)) 1456 return -EFAULT; 1457 1458 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1459 if (!buf_prevkey) 1460 return -ENOMEM; 1461 1462 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1463 if (!buf) { 1464 kvfree(buf_prevkey); 1465 return -ENOMEM; 1466 } 1467 1468 err = -EFAULT; 1469 prev_key = NULL; 1470 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1471 goto free_buf; 1472 key = buf; 1473 value = key + map->key_size; 1474 if (ubatch) 1475 prev_key = buf_prevkey; 1476 1477 for (cp = 0; cp < max_count;) { 1478 rcu_read_lock(); 1479 err = map->ops->map_get_next_key(map, prev_key, key); 1480 rcu_read_unlock(); 1481 if (err) 1482 break; 1483 err = bpf_map_copy_value(map, key, value, 1484 attr->batch.elem_flags); 1485 1486 if (err == -ENOENT) { 1487 if (retry) { 1488 retry--; 1489 continue; 1490 } 1491 err = -EINTR; 1492 break; 1493 } 1494 1495 if (err) 1496 goto free_buf; 1497 1498 if (copy_to_user(keys + cp * map->key_size, key, 1499 map->key_size)) { 1500 err = -EFAULT; 1501 goto free_buf; 1502 } 1503 if (copy_to_user(values + cp * value_size, value, value_size)) { 1504 err = -EFAULT; 1505 goto free_buf; 1506 } 1507 1508 if (!prev_key) 1509 prev_key = buf_prevkey; 1510 1511 swap(prev_key, key); 1512 retry = MAP_LOOKUP_RETRIES; 1513 cp++; 1514 cond_resched(); 1515 } 1516 1517 if (err == -EFAULT) 1518 goto free_buf; 1519 1520 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1521 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1522 err = -EFAULT; 1523 1524 free_buf: 1525 kvfree(buf_prevkey); 1526 kvfree(buf); 1527 return err; 1528 } 1529 1530 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 1531 1532 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1533 { 1534 void __user *ukey = u64_to_user_ptr(attr->key); 1535 void __user *uvalue = u64_to_user_ptr(attr->value); 1536 int ufd = attr->map_fd; 1537 struct bpf_map *map; 1538 void *key, *value; 1539 u32 value_size; 1540 struct fd f; 1541 int err; 1542 1543 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1544 return -EINVAL; 1545 1546 if (attr->flags & ~BPF_F_LOCK) 1547 return -EINVAL; 1548 1549 f = fdget(ufd); 1550 map = __bpf_map_get(f); 1551 if (IS_ERR(map)) 1552 return PTR_ERR(map); 1553 bpf_map_write_active_inc(map); 1554 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 1555 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1556 err = -EPERM; 1557 goto err_put; 1558 } 1559 1560 if (attr->flags && 1561 (map->map_type == BPF_MAP_TYPE_QUEUE || 1562 map->map_type == BPF_MAP_TYPE_STACK)) { 1563 err = -EINVAL; 1564 goto err_put; 1565 } 1566 1567 if ((attr->flags & BPF_F_LOCK) && 1568 !map_value_has_spin_lock(map)) { 1569 err = -EINVAL; 1570 goto err_put; 1571 } 1572 1573 key = __bpf_copy_key(ukey, map->key_size); 1574 if (IS_ERR(key)) { 1575 err = PTR_ERR(key); 1576 goto err_put; 1577 } 1578 1579 value_size = bpf_map_value_size(map); 1580 1581 err = -ENOMEM; 1582 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1583 if (!value) 1584 goto free_key; 1585 1586 err = -ENOTSUPP; 1587 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1588 map->map_type == BPF_MAP_TYPE_STACK) { 1589 err = map->ops->map_pop_elem(map, value); 1590 } else if (map->map_type == BPF_MAP_TYPE_HASH || 1591 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1592 map->map_type == BPF_MAP_TYPE_LRU_HASH || 1593 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 1594 if (!bpf_map_is_dev_bound(map)) { 1595 bpf_disable_instrumentation(); 1596 rcu_read_lock(); 1597 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 1598 rcu_read_unlock(); 1599 bpf_enable_instrumentation(); 1600 } 1601 } 1602 1603 if (err) 1604 goto free_value; 1605 1606 if (copy_to_user(uvalue, value, value_size) != 0) { 1607 err = -EFAULT; 1608 goto free_value; 1609 } 1610 1611 err = 0; 1612 1613 free_value: 1614 kvfree(value); 1615 free_key: 1616 kvfree(key); 1617 err_put: 1618 bpf_map_write_active_dec(map); 1619 fdput(f); 1620 return err; 1621 } 1622 1623 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1624 1625 static int map_freeze(const union bpf_attr *attr) 1626 { 1627 int err = 0, ufd = attr->map_fd; 1628 struct bpf_map *map; 1629 struct fd f; 1630 1631 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1632 return -EINVAL; 1633 1634 f = fdget(ufd); 1635 map = __bpf_map_get(f); 1636 if (IS_ERR(map)) 1637 return PTR_ERR(map); 1638 1639 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || 1640 map_value_has_timer(map)) { 1641 fdput(f); 1642 return -ENOTSUPP; 1643 } 1644 1645 mutex_lock(&map->freeze_mutex); 1646 if (bpf_map_write_active(map)) { 1647 err = -EBUSY; 1648 goto err_put; 1649 } 1650 if (READ_ONCE(map->frozen)) { 1651 err = -EBUSY; 1652 goto err_put; 1653 } 1654 if (!bpf_capable()) { 1655 err = -EPERM; 1656 goto err_put; 1657 } 1658 1659 WRITE_ONCE(map->frozen, true); 1660 err_put: 1661 mutex_unlock(&map->freeze_mutex); 1662 fdput(f); 1663 return err; 1664 } 1665 1666 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1667 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1668 [_id] = & _name ## _prog_ops, 1669 #define BPF_MAP_TYPE(_id, _ops) 1670 #define BPF_LINK_TYPE(_id, _name) 1671 #include <linux/bpf_types.h> 1672 #undef BPF_PROG_TYPE 1673 #undef BPF_MAP_TYPE 1674 #undef BPF_LINK_TYPE 1675 }; 1676 1677 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1678 { 1679 const struct bpf_prog_ops *ops; 1680 1681 if (type >= ARRAY_SIZE(bpf_prog_types)) 1682 return -EINVAL; 1683 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1684 ops = bpf_prog_types[type]; 1685 if (!ops) 1686 return -EINVAL; 1687 1688 if (!bpf_prog_is_dev_bound(prog->aux)) 1689 prog->aux->ops = ops; 1690 else 1691 prog->aux->ops = &bpf_offload_prog_ops; 1692 prog->type = type; 1693 return 0; 1694 } 1695 1696 enum bpf_audit { 1697 BPF_AUDIT_LOAD, 1698 BPF_AUDIT_UNLOAD, 1699 BPF_AUDIT_MAX, 1700 }; 1701 1702 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1703 [BPF_AUDIT_LOAD] = "LOAD", 1704 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1705 }; 1706 1707 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1708 { 1709 struct audit_context *ctx = NULL; 1710 struct audit_buffer *ab; 1711 1712 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1713 return; 1714 if (audit_enabled == AUDIT_OFF) 1715 return; 1716 if (op == BPF_AUDIT_LOAD) 1717 ctx = audit_context(); 1718 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1719 if (unlikely(!ab)) 1720 return; 1721 audit_log_format(ab, "prog-id=%u op=%s", 1722 prog->aux->id, bpf_audit_str[op]); 1723 audit_log_end(ab); 1724 } 1725 1726 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1727 { 1728 int id; 1729 1730 idr_preload(GFP_KERNEL); 1731 spin_lock_bh(&prog_idr_lock); 1732 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1733 if (id > 0) 1734 prog->aux->id = id; 1735 spin_unlock_bh(&prog_idr_lock); 1736 idr_preload_end(); 1737 1738 /* id is in [1, INT_MAX) */ 1739 if (WARN_ON_ONCE(!id)) 1740 return -ENOSPC; 1741 1742 return id > 0 ? 0 : id; 1743 } 1744 1745 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1746 { 1747 unsigned long flags; 1748 1749 /* cBPF to eBPF migrations are currently not in the idr store. 1750 * Offloaded programs are removed from the store when their device 1751 * disappears - even if someone grabs an fd to them they are unusable, 1752 * simply waiting for refcnt to drop to be freed. 1753 */ 1754 if (!prog->aux->id) 1755 return; 1756 1757 if (do_idr_lock) 1758 spin_lock_irqsave(&prog_idr_lock, flags); 1759 else 1760 __acquire(&prog_idr_lock); 1761 1762 idr_remove(&prog_idr, prog->aux->id); 1763 prog->aux->id = 0; 1764 1765 if (do_idr_lock) 1766 spin_unlock_irqrestore(&prog_idr_lock, flags); 1767 else 1768 __release(&prog_idr_lock); 1769 } 1770 1771 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1772 { 1773 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1774 1775 kvfree(aux->func_info); 1776 kfree(aux->func_info_aux); 1777 free_uid(aux->user); 1778 security_bpf_prog_free(aux); 1779 bpf_prog_free(aux->prog); 1780 } 1781 1782 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1783 { 1784 bpf_prog_kallsyms_del_all(prog); 1785 btf_put(prog->aux->btf); 1786 kvfree(prog->aux->jited_linfo); 1787 kvfree(prog->aux->linfo); 1788 kfree(prog->aux->kfunc_tab); 1789 if (prog->aux->attach_btf) 1790 btf_put(prog->aux->attach_btf); 1791 1792 if (deferred) { 1793 if (prog->aux->sleepable) 1794 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 1795 else 1796 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1797 } else { 1798 __bpf_prog_put_rcu(&prog->aux->rcu); 1799 } 1800 } 1801 1802 static void bpf_prog_put_deferred(struct work_struct *work) 1803 { 1804 struct bpf_prog_aux *aux; 1805 struct bpf_prog *prog; 1806 1807 aux = container_of(work, struct bpf_prog_aux, work); 1808 prog = aux->prog; 1809 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1810 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1811 __bpf_prog_put_noref(prog, true); 1812 } 1813 1814 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1815 { 1816 struct bpf_prog_aux *aux = prog->aux; 1817 1818 if (atomic64_dec_and_test(&aux->refcnt)) { 1819 /* bpf_prog_free_id() must be called first */ 1820 bpf_prog_free_id(prog, do_idr_lock); 1821 1822 if (in_irq() || irqs_disabled()) { 1823 INIT_WORK(&aux->work, bpf_prog_put_deferred); 1824 schedule_work(&aux->work); 1825 } else { 1826 bpf_prog_put_deferred(&aux->work); 1827 } 1828 } 1829 } 1830 1831 void bpf_prog_put(struct bpf_prog *prog) 1832 { 1833 __bpf_prog_put(prog, true); 1834 } 1835 EXPORT_SYMBOL_GPL(bpf_prog_put); 1836 1837 static int bpf_prog_release(struct inode *inode, struct file *filp) 1838 { 1839 struct bpf_prog *prog = filp->private_data; 1840 1841 bpf_prog_put(prog); 1842 return 0; 1843 } 1844 1845 struct bpf_prog_kstats { 1846 u64 nsecs; 1847 u64 cnt; 1848 u64 misses; 1849 }; 1850 1851 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1852 struct bpf_prog_kstats *stats) 1853 { 1854 u64 nsecs = 0, cnt = 0, misses = 0; 1855 int cpu; 1856 1857 for_each_possible_cpu(cpu) { 1858 const struct bpf_prog_stats *st; 1859 unsigned int start; 1860 u64 tnsecs, tcnt, tmisses; 1861 1862 st = per_cpu_ptr(prog->stats, cpu); 1863 do { 1864 start = u64_stats_fetch_begin_irq(&st->syncp); 1865 tnsecs = u64_stats_read(&st->nsecs); 1866 tcnt = u64_stats_read(&st->cnt); 1867 tmisses = u64_stats_read(&st->misses); 1868 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1869 nsecs += tnsecs; 1870 cnt += tcnt; 1871 misses += tmisses; 1872 } 1873 stats->nsecs = nsecs; 1874 stats->cnt = cnt; 1875 stats->misses = misses; 1876 } 1877 1878 #ifdef CONFIG_PROC_FS 1879 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1880 { 1881 const struct bpf_prog *prog = filp->private_data; 1882 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1883 struct bpf_prog_kstats stats; 1884 1885 bpf_prog_get_stats(prog, &stats); 1886 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1887 seq_printf(m, 1888 "prog_type:\t%u\n" 1889 "prog_jited:\t%u\n" 1890 "prog_tag:\t%s\n" 1891 "memlock:\t%llu\n" 1892 "prog_id:\t%u\n" 1893 "run_time_ns:\t%llu\n" 1894 "run_cnt:\t%llu\n" 1895 "recursion_misses:\t%llu\n" 1896 "verified_insns:\t%u\n", 1897 prog->type, 1898 prog->jited, 1899 prog_tag, 1900 prog->pages * 1ULL << PAGE_SHIFT, 1901 prog->aux->id, 1902 stats.nsecs, 1903 stats.cnt, 1904 stats.misses, 1905 prog->aux->verified_insns); 1906 } 1907 #endif 1908 1909 const struct file_operations bpf_prog_fops = { 1910 #ifdef CONFIG_PROC_FS 1911 .show_fdinfo = bpf_prog_show_fdinfo, 1912 #endif 1913 .release = bpf_prog_release, 1914 .read = bpf_dummy_read, 1915 .write = bpf_dummy_write, 1916 }; 1917 1918 int bpf_prog_new_fd(struct bpf_prog *prog) 1919 { 1920 int ret; 1921 1922 ret = security_bpf_prog(prog); 1923 if (ret < 0) 1924 return ret; 1925 1926 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1927 O_RDWR | O_CLOEXEC); 1928 } 1929 1930 static struct bpf_prog *____bpf_prog_get(struct fd f) 1931 { 1932 if (!f.file) 1933 return ERR_PTR(-EBADF); 1934 if (f.file->f_op != &bpf_prog_fops) { 1935 fdput(f); 1936 return ERR_PTR(-EINVAL); 1937 } 1938 1939 return f.file->private_data; 1940 } 1941 1942 void bpf_prog_add(struct bpf_prog *prog, int i) 1943 { 1944 atomic64_add(i, &prog->aux->refcnt); 1945 } 1946 EXPORT_SYMBOL_GPL(bpf_prog_add); 1947 1948 void bpf_prog_sub(struct bpf_prog *prog, int i) 1949 { 1950 /* Only to be used for undoing previous bpf_prog_add() in some 1951 * error path. We still know that another entity in our call 1952 * path holds a reference to the program, thus atomic_sub() can 1953 * be safely used in such cases! 1954 */ 1955 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1956 } 1957 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1958 1959 void bpf_prog_inc(struct bpf_prog *prog) 1960 { 1961 atomic64_inc(&prog->aux->refcnt); 1962 } 1963 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1964 1965 /* prog_idr_lock should have been held */ 1966 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1967 { 1968 int refold; 1969 1970 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1971 1972 if (!refold) 1973 return ERR_PTR(-ENOENT); 1974 1975 return prog; 1976 } 1977 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1978 1979 bool bpf_prog_get_ok(struct bpf_prog *prog, 1980 enum bpf_prog_type *attach_type, bool attach_drv) 1981 { 1982 /* not an attachment, just a refcount inc, always allow */ 1983 if (!attach_type) 1984 return true; 1985 1986 if (prog->type != *attach_type) 1987 return false; 1988 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1989 return false; 1990 1991 return true; 1992 } 1993 1994 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1995 bool attach_drv) 1996 { 1997 struct fd f = fdget(ufd); 1998 struct bpf_prog *prog; 1999 2000 prog = ____bpf_prog_get(f); 2001 if (IS_ERR(prog)) 2002 return prog; 2003 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 2004 prog = ERR_PTR(-EINVAL); 2005 goto out; 2006 } 2007 2008 bpf_prog_inc(prog); 2009 out: 2010 fdput(f); 2011 return prog; 2012 } 2013 2014 struct bpf_prog *bpf_prog_get(u32 ufd) 2015 { 2016 return __bpf_prog_get(ufd, NULL, false); 2017 } 2018 2019 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2020 bool attach_drv) 2021 { 2022 return __bpf_prog_get(ufd, &type, attach_drv); 2023 } 2024 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2025 2026 /* Initially all BPF programs could be loaded w/o specifying 2027 * expected_attach_type. Later for some of them specifying expected_attach_type 2028 * at load time became required so that program could be validated properly. 2029 * Programs of types that are allowed to be loaded both w/ and w/o (for 2030 * backward compatibility) expected_attach_type, should have the default attach 2031 * type assigned to expected_attach_type for the latter case, so that it can be 2032 * validated later at attach time. 2033 * 2034 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2035 * prog type requires it but has some attach types that have to be backward 2036 * compatible. 2037 */ 2038 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2039 { 2040 switch (attr->prog_type) { 2041 case BPF_PROG_TYPE_CGROUP_SOCK: 2042 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2043 * exist so checking for non-zero is the way to go here. 2044 */ 2045 if (!attr->expected_attach_type) 2046 attr->expected_attach_type = 2047 BPF_CGROUP_INET_SOCK_CREATE; 2048 break; 2049 case BPF_PROG_TYPE_SK_REUSEPORT: 2050 if (!attr->expected_attach_type) 2051 attr->expected_attach_type = 2052 BPF_SK_REUSEPORT_SELECT; 2053 break; 2054 } 2055 } 2056 2057 static int 2058 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2059 enum bpf_attach_type expected_attach_type, 2060 struct btf *attach_btf, u32 btf_id, 2061 struct bpf_prog *dst_prog) 2062 { 2063 if (btf_id) { 2064 if (btf_id > BTF_MAX_TYPE) 2065 return -EINVAL; 2066 2067 if (!attach_btf && !dst_prog) 2068 return -EINVAL; 2069 2070 switch (prog_type) { 2071 case BPF_PROG_TYPE_TRACING: 2072 case BPF_PROG_TYPE_LSM: 2073 case BPF_PROG_TYPE_STRUCT_OPS: 2074 case BPF_PROG_TYPE_EXT: 2075 break; 2076 default: 2077 return -EINVAL; 2078 } 2079 } 2080 2081 if (attach_btf && (!btf_id || dst_prog)) 2082 return -EINVAL; 2083 2084 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2085 prog_type != BPF_PROG_TYPE_EXT) 2086 return -EINVAL; 2087 2088 switch (prog_type) { 2089 case BPF_PROG_TYPE_CGROUP_SOCK: 2090 switch (expected_attach_type) { 2091 case BPF_CGROUP_INET_SOCK_CREATE: 2092 case BPF_CGROUP_INET_SOCK_RELEASE: 2093 case BPF_CGROUP_INET4_POST_BIND: 2094 case BPF_CGROUP_INET6_POST_BIND: 2095 return 0; 2096 default: 2097 return -EINVAL; 2098 } 2099 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2100 switch (expected_attach_type) { 2101 case BPF_CGROUP_INET4_BIND: 2102 case BPF_CGROUP_INET6_BIND: 2103 case BPF_CGROUP_INET4_CONNECT: 2104 case BPF_CGROUP_INET6_CONNECT: 2105 case BPF_CGROUP_INET4_GETPEERNAME: 2106 case BPF_CGROUP_INET6_GETPEERNAME: 2107 case BPF_CGROUP_INET4_GETSOCKNAME: 2108 case BPF_CGROUP_INET6_GETSOCKNAME: 2109 case BPF_CGROUP_UDP4_SENDMSG: 2110 case BPF_CGROUP_UDP6_SENDMSG: 2111 case BPF_CGROUP_UDP4_RECVMSG: 2112 case BPF_CGROUP_UDP6_RECVMSG: 2113 return 0; 2114 default: 2115 return -EINVAL; 2116 } 2117 case BPF_PROG_TYPE_CGROUP_SKB: 2118 switch (expected_attach_type) { 2119 case BPF_CGROUP_INET_INGRESS: 2120 case BPF_CGROUP_INET_EGRESS: 2121 return 0; 2122 default: 2123 return -EINVAL; 2124 } 2125 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2126 switch (expected_attach_type) { 2127 case BPF_CGROUP_SETSOCKOPT: 2128 case BPF_CGROUP_GETSOCKOPT: 2129 return 0; 2130 default: 2131 return -EINVAL; 2132 } 2133 case BPF_PROG_TYPE_SK_LOOKUP: 2134 if (expected_attach_type == BPF_SK_LOOKUP) 2135 return 0; 2136 return -EINVAL; 2137 case BPF_PROG_TYPE_SK_REUSEPORT: 2138 switch (expected_attach_type) { 2139 case BPF_SK_REUSEPORT_SELECT: 2140 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2141 return 0; 2142 default: 2143 return -EINVAL; 2144 } 2145 case BPF_PROG_TYPE_SYSCALL: 2146 case BPF_PROG_TYPE_EXT: 2147 if (expected_attach_type) 2148 return -EINVAL; 2149 fallthrough; 2150 default: 2151 return 0; 2152 } 2153 } 2154 2155 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2156 { 2157 switch (prog_type) { 2158 case BPF_PROG_TYPE_SCHED_CLS: 2159 case BPF_PROG_TYPE_SCHED_ACT: 2160 case BPF_PROG_TYPE_XDP: 2161 case BPF_PROG_TYPE_LWT_IN: 2162 case BPF_PROG_TYPE_LWT_OUT: 2163 case BPF_PROG_TYPE_LWT_XMIT: 2164 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2165 case BPF_PROG_TYPE_SK_SKB: 2166 case BPF_PROG_TYPE_SK_MSG: 2167 case BPF_PROG_TYPE_LIRC_MODE2: 2168 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2169 case BPF_PROG_TYPE_CGROUP_DEVICE: 2170 case BPF_PROG_TYPE_CGROUP_SOCK: 2171 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2172 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2173 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2174 case BPF_PROG_TYPE_SOCK_OPS: 2175 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2176 return true; 2177 case BPF_PROG_TYPE_CGROUP_SKB: 2178 /* always unpriv */ 2179 case BPF_PROG_TYPE_SK_REUSEPORT: 2180 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2181 default: 2182 return false; 2183 } 2184 } 2185 2186 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2187 { 2188 switch (prog_type) { 2189 case BPF_PROG_TYPE_KPROBE: 2190 case BPF_PROG_TYPE_TRACEPOINT: 2191 case BPF_PROG_TYPE_PERF_EVENT: 2192 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2193 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2194 case BPF_PROG_TYPE_TRACING: 2195 case BPF_PROG_TYPE_LSM: 2196 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2197 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2198 return true; 2199 default: 2200 return false; 2201 } 2202 } 2203 2204 /* last field in 'union bpf_attr' used by this command */ 2205 #define BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size 2206 2207 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr) 2208 { 2209 enum bpf_prog_type type = attr->prog_type; 2210 struct bpf_prog *prog, *dst_prog = NULL; 2211 struct btf *attach_btf = NULL; 2212 int err; 2213 char license[128]; 2214 bool is_gpl; 2215 2216 if (CHECK_ATTR(BPF_PROG_LOAD)) 2217 return -EINVAL; 2218 2219 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2220 BPF_F_ANY_ALIGNMENT | 2221 BPF_F_TEST_STATE_FREQ | 2222 BPF_F_SLEEPABLE | 2223 BPF_F_TEST_RND_HI32)) 2224 return -EINVAL; 2225 2226 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2227 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2228 !bpf_capable()) 2229 return -EPERM; 2230 2231 /* copy eBPF program license from user space */ 2232 if (strncpy_from_bpfptr(license, 2233 make_bpfptr(attr->license, uattr.is_kernel), 2234 sizeof(license) - 1) < 0) 2235 return -EFAULT; 2236 license[sizeof(license) - 1] = 0; 2237 2238 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2239 is_gpl = license_is_gpl_compatible(license); 2240 2241 if (attr->insn_cnt == 0 || 2242 attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2243 return -E2BIG; 2244 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2245 type != BPF_PROG_TYPE_CGROUP_SKB && 2246 !bpf_capable()) 2247 return -EPERM; 2248 2249 if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN)) 2250 return -EPERM; 2251 if (is_perfmon_prog_type(type) && !perfmon_capable()) 2252 return -EPERM; 2253 2254 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2255 * or btf, we need to check which one it is 2256 */ 2257 if (attr->attach_prog_fd) { 2258 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2259 if (IS_ERR(dst_prog)) { 2260 dst_prog = NULL; 2261 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2262 if (IS_ERR(attach_btf)) 2263 return -EINVAL; 2264 if (!btf_is_kernel(attach_btf)) { 2265 /* attaching through specifying bpf_prog's BTF 2266 * objects directly might be supported eventually 2267 */ 2268 btf_put(attach_btf); 2269 return -ENOTSUPP; 2270 } 2271 } 2272 } else if (attr->attach_btf_id) { 2273 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2274 attach_btf = bpf_get_btf_vmlinux(); 2275 if (IS_ERR(attach_btf)) 2276 return PTR_ERR(attach_btf); 2277 if (!attach_btf) 2278 return -EINVAL; 2279 btf_get(attach_btf); 2280 } 2281 2282 bpf_prog_load_fixup_attach_type(attr); 2283 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2284 attach_btf, attr->attach_btf_id, 2285 dst_prog)) { 2286 if (dst_prog) 2287 bpf_prog_put(dst_prog); 2288 if (attach_btf) 2289 btf_put(attach_btf); 2290 return -EINVAL; 2291 } 2292 2293 /* plain bpf_prog allocation */ 2294 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2295 if (!prog) { 2296 if (dst_prog) 2297 bpf_prog_put(dst_prog); 2298 if (attach_btf) 2299 btf_put(attach_btf); 2300 return -ENOMEM; 2301 } 2302 2303 prog->expected_attach_type = attr->expected_attach_type; 2304 prog->aux->attach_btf = attach_btf; 2305 prog->aux->attach_btf_id = attr->attach_btf_id; 2306 prog->aux->dst_prog = dst_prog; 2307 prog->aux->offload_requested = !!attr->prog_ifindex; 2308 prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; 2309 2310 err = security_bpf_prog_alloc(prog->aux); 2311 if (err) 2312 goto free_prog; 2313 2314 prog->aux->user = get_current_user(); 2315 prog->len = attr->insn_cnt; 2316 2317 err = -EFAULT; 2318 if (copy_from_bpfptr(prog->insns, 2319 make_bpfptr(attr->insns, uattr.is_kernel), 2320 bpf_prog_insn_size(prog)) != 0) 2321 goto free_prog_sec; 2322 2323 prog->orig_prog = NULL; 2324 prog->jited = 0; 2325 2326 atomic64_set(&prog->aux->refcnt, 1); 2327 prog->gpl_compatible = is_gpl ? 1 : 0; 2328 2329 if (bpf_prog_is_dev_bound(prog->aux)) { 2330 err = bpf_prog_offload_init(prog, attr); 2331 if (err) 2332 goto free_prog_sec; 2333 } 2334 2335 /* find program type: socket_filter vs tracing_filter */ 2336 err = find_prog_type(type, prog); 2337 if (err < 0) 2338 goto free_prog_sec; 2339 2340 prog->aux->load_time = ktime_get_boottime_ns(); 2341 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2342 sizeof(attr->prog_name)); 2343 if (err < 0) 2344 goto free_prog_sec; 2345 2346 /* run eBPF verifier */ 2347 err = bpf_check(&prog, attr, uattr); 2348 if (err < 0) 2349 goto free_used_maps; 2350 2351 prog = bpf_prog_select_runtime(prog, &err); 2352 if (err < 0) 2353 goto free_used_maps; 2354 2355 err = bpf_prog_alloc_id(prog); 2356 if (err) 2357 goto free_used_maps; 2358 2359 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2360 * effectively publicly exposed. However, retrieving via 2361 * bpf_prog_get_fd_by_id() will take another reference, 2362 * therefore it cannot be gone underneath us. 2363 * 2364 * Only for the time /after/ successful bpf_prog_new_fd() 2365 * and before returning to userspace, we might just hold 2366 * one reference and any parallel close on that fd could 2367 * rip everything out. Hence, below notifications must 2368 * happen before bpf_prog_new_fd(). 2369 * 2370 * Also, any failure handling from this point onwards must 2371 * be using bpf_prog_put() given the program is exposed. 2372 */ 2373 bpf_prog_kallsyms_add(prog); 2374 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2375 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2376 2377 err = bpf_prog_new_fd(prog); 2378 if (err < 0) 2379 bpf_prog_put(prog); 2380 return err; 2381 2382 free_used_maps: 2383 /* In case we have subprogs, we need to wait for a grace 2384 * period before we can tear down JIT memory since symbols 2385 * are already exposed under kallsyms. 2386 */ 2387 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2388 return err; 2389 free_prog_sec: 2390 free_uid(prog->aux->user); 2391 security_bpf_prog_free(prog->aux); 2392 free_prog: 2393 if (prog->aux->attach_btf) 2394 btf_put(prog->aux->attach_btf); 2395 bpf_prog_free(prog); 2396 return err; 2397 } 2398 2399 #define BPF_OBJ_LAST_FIELD file_flags 2400 2401 static int bpf_obj_pin(const union bpf_attr *attr) 2402 { 2403 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2404 return -EINVAL; 2405 2406 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2407 } 2408 2409 static int bpf_obj_get(const union bpf_attr *attr) 2410 { 2411 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2412 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2413 return -EINVAL; 2414 2415 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2416 attr->file_flags); 2417 } 2418 2419 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2420 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2421 { 2422 atomic64_set(&link->refcnt, 1); 2423 link->type = type; 2424 link->id = 0; 2425 link->ops = ops; 2426 link->prog = prog; 2427 } 2428 2429 static void bpf_link_free_id(int id) 2430 { 2431 if (!id) 2432 return; 2433 2434 spin_lock_bh(&link_idr_lock); 2435 idr_remove(&link_idr, id); 2436 spin_unlock_bh(&link_idr_lock); 2437 } 2438 2439 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2440 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2441 * anon_inode's release() call. This helper marksbpf_link as 2442 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 2443 * is not decremented, it's the responsibility of a calling code that failed 2444 * to complete bpf_link initialization. 2445 */ 2446 void bpf_link_cleanup(struct bpf_link_primer *primer) 2447 { 2448 primer->link->prog = NULL; 2449 bpf_link_free_id(primer->id); 2450 fput(primer->file); 2451 put_unused_fd(primer->fd); 2452 } 2453 2454 void bpf_link_inc(struct bpf_link *link) 2455 { 2456 atomic64_inc(&link->refcnt); 2457 } 2458 2459 /* bpf_link_free is guaranteed to be called from process context */ 2460 static void bpf_link_free(struct bpf_link *link) 2461 { 2462 bpf_link_free_id(link->id); 2463 if (link->prog) { 2464 /* detach BPF program, clean up used resources */ 2465 link->ops->release(link); 2466 bpf_prog_put(link->prog); 2467 } 2468 /* free bpf_link and its containing memory */ 2469 link->ops->dealloc(link); 2470 } 2471 2472 static void bpf_link_put_deferred(struct work_struct *work) 2473 { 2474 struct bpf_link *link = container_of(work, struct bpf_link, work); 2475 2476 bpf_link_free(link); 2477 } 2478 2479 /* bpf_link_put can be called from atomic context, but ensures that resources 2480 * are freed from process context 2481 */ 2482 void bpf_link_put(struct bpf_link *link) 2483 { 2484 if (!atomic64_dec_and_test(&link->refcnt)) 2485 return; 2486 2487 if (in_atomic()) { 2488 INIT_WORK(&link->work, bpf_link_put_deferred); 2489 schedule_work(&link->work); 2490 } else { 2491 bpf_link_free(link); 2492 } 2493 } 2494 2495 static int bpf_link_release(struct inode *inode, struct file *filp) 2496 { 2497 struct bpf_link *link = filp->private_data; 2498 2499 bpf_link_put(link); 2500 return 0; 2501 } 2502 2503 #ifdef CONFIG_PROC_FS 2504 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 2505 #define BPF_MAP_TYPE(_id, _ops) 2506 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 2507 static const char *bpf_link_type_strs[] = { 2508 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 2509 #include <linux/bpf_types.h> 2510 }; 2511 #undef BPF_PROG_TYPE 2512 #undef BPF_MAP_TYPE 2513 #undef BPF_LINK_TYPE 2514 2515 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2516 { 2517 const struct bpf_link *link = filp->private_data; 2518 const struct bpf_prog *prog = link->prog; 2519 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2520 2521 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2522 seq_printf(m, 2523 "link_type:\t%s\n" 2524 "link_id:\t%u\n" 2525 "prog_tag:\t%s\n" 2526 "prog_id:\t%u\n", 2527 bpf_link_type_strs[link->type], 2528 link->id, 2529 prog_tag, 2530 prog->aux->id); 2531 if (link->ops->show_fdinfo) 2532 link->ops->show_fdinfo(link, m); 2533 } 2534 #endif 2535 2536 static const struct file_operations bpf_link_fops = { 2537 #ifdef CONFIG_PROC_FS 2538 .show_fdinfo = bpf_link_show_fdinfo, 2539 #endif 2540 .release = bpf_link_release, 2541 .read = bpf_dummy_read, 2542 .write = bpf_dummy_write, 2543 }; 2544 2545 static int bpf_link_alloc_id(struct bpf_link *link) 2546 { 2547 int id; 2548 2549 idr_preload(GFP_KERNEL); 2550 spin_lock_bh(&link_idr_lock); 2551 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 2552 spin_unlock_bh(&link_idr_lock); 2553 idr_preload_end(); 2554 2555 return id; 2556 } 2557 2558 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 2559 * reserving unused FD and allocating ID from link_idr. This is to be paired 2560 * with bpf_link_settle() to install FD and ID and expose bpf_link to 2561 * user-space, if bpf_link is successfully attached. If not, bpf_link and 2562 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 2563 * transient state is passed around in struct bpf_link_primer. 2564 * This is preferred way to create and initialize bpf_link, especially when 2565 * there are complicated and expensive operations inbetween creating bpf_link 2566 * itself and attaching it to BPF hook. By using bpf_link_prime() and 2567 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 2568 * expensive (and potentially failing) roll back operations in a rare case 2569 * that file, FD, or ID can't be allocated. 2570 */ 2571 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 2572 { 2573 struct file *file; 2574 int fd, id; 2575 2576 fd = get_unused_fd_flags(O_CLOEXEC); 2577 if (fd < 0) 2578 return fd; 2579 2580 2581 id = bpf_link_alloc_id(link); 2582 if (id < 0) { 2583 put_unused_fd(fd); 2584 return id; 2585 } 2586 2587 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2588 if (IS_ERR(file)) { 2589 bpf_link_free_id(id); 2590 put_unused_fd(fd); 2591 return PTR_ERR(file); 2592 } 2593 2594 primer->link = link; 2595 primer->file = file; 2596 primer->fd = fd; 2597 primer->id = id; 2598 return 0; 2599 } 2600 2601 int bpf_link_settle(struct bpf_link_primer *primer) 2602 { 2603 /* make bpf_link fetchable by ID */ 2604 spin_lock_bh(&link_idr_lock); 2605 primer->link->id = primer->id; 2606 spin_unlock_bh(&link_idr_lock); 2607 /* make bpf_link fetchable by FD */ 2608 fd_install(primer->fd, primer->file); 2609 /* pass through installed FD */ 2610 return primer->fd; 2611 } 2612 2613 int bpf_link_new_fd(struct bpf_link *link) 2614 { 2615 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2616 } 2617 2618 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2619 { 2620 struct fd f = fdget(ufd); 2621 struct bpf_link *link; 2622 2623 if (!f.file) 2624 return ERR_PTR(-EBADF); 2625 if (f.file->f_op != &bpf_link_fops) { 2626 fdput(f); 2627 return ERR_PTR(-EINVAL); 2628 } 2629 2630 link = f.file->private_data; 2631 bpf_link_inc(link); 2632 fdput(f); 2633 2634 return link; 2635 } 2636 2637 struct bpf_tracing_link { 2638 struct bpf_link link; 2639 enum bpf_attach_type attach_type; 2640 struct bpf_trampoline *trampoline; 2641 struct bpf_prog *tgt_prog; 2642 }; 2643 2644 static void bpf_tracing_link_release(struct bpf_link *link) 2645 { 2646 struct bpf_tracing_link *tr_link = 2647 container_of(link, struct bpf_tracing_link, link); 2648 2649 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, 2650 tr_link->trampoline)); 2651 2652 bpf_trampoline_put(tr_link->trampoline); 2653 2654 /* tgt_prog is NULL if target is a kernel function */ 2655 if (tr_link->tgt_prog) 2656 bpf_prog_put(tr_link->tgt_prog); 2657 } 2658 2659 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2660 { 2661 struct bpf_tracing_link *tr_link = 2662 container_of(link, struct bpf_tracing_link, link); 2663 2664 kfree(tr_link); 2665 } 2666 2667 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 2668 struct seq_file *seq) 2669 { 2670 struct bpf_tracing_link *tr_link = 2671 container_of(link, struct bpf_tracing_link, link); 2672 2673 seq_printf(seq, 2674 "attach_type:\t%d\n", 2675 tr_link->attach_type); 2676 } 2677 2678 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 2679 struct bpf_link_info *info) 2680 { 2681 struct bpf_tracing_link *tr_link = 2682 container_of(link, struct bpf_tracing_link, link); 2683 2684 info->tracing.attach_type = tr_link->attach_type; 2685 bpf_trampoline_unpack_key(tr_link->trampoline->key, 2686 &info->tracing.target_obj_id, 2687 &info->tracing.target_btf_id); 2688 2689 return 0; 2690 } 2691 2692 static const struct bpf_link_ops bpf_tracing_link_lops = { 2693 .release = bpf_tracing_link_release, 2694 .dealloc = bpf_tracing_link_dealloc, 2695 .show_fdinfo = bpf_tracing_link_show_fdinfo, 2696 .fill_link_info = bpf_tracing_link_fill_link_info, 2697 }; 2698 2699 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 2700 int tgt_prog_fd, 2701 u32 btf_id) 2702 { 2703 struct bpf_link_primer link_primer; 2704 struct bpf_prog *tgt_prog = NULL; 2705 struct bpf_trampoline *tr = NULL; 2706 struct bpf_tracing_link *link; 2707 u64 key = 0; 2708 int err; 2709 2710 switch (prog->type) { 2711 case BPF_PROG_TYPE_TRACING: 2712 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2713 prog->expected_attach_type != BPF_TRACE_FEXIT && 2714 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2715 err = -EINVAL; 2716 goto out_put_prog; 2717 } 2718 break; 2719 case BPF_PROG_TYPE_EXT: 2720 if (prog->expected_attach_type != 0) { 2721 err = -EINVAL; 2722 goto out_put_prog; 2723 } 2724 break; 2725 case BPF_PROG_TYPE_LSM: 2726 if (prog->expected_attach_type != BPF_LSM_MAC) { 2727 err = -EINVAL; 2728 goto out_put_prog; 2729 } 2730 break; 2731 default: 2732 err = -EINVAL; 2733 goto out_put_prog; 2734 } 2735 2736 if (!!tgt_prog_fd != !!btf_id) { 2737 err = -EINVAL; 2738 goto out_put_prog; 2739 } 2740 2741 if (tgt_prog_fd) { 2742 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */ 2743 if (prog->type != BPF_PROG_TYPE_EXT) { 2744 err = -EINVAL; 2745 goto out_put_prog; 2746 } 2747 2748 tgt_prog = bpf_prog_get(tgt_prog_fd); 2749 if (IS_ERR(tgt_prog)) { 2750 err = PTR_ERR(tgt_prog); 2751 tgt_prog = NULL; 2752 goto out_put_prog; 2753 } 2754 2755 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 2756 } 2757 2758 link = kzalloc(sizeof(*link), GFP_USER); 2759 if (!link) { 2760 err = -ENOMEM; 2761 goto out_put_prog; 2762 } 2763 bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, 2764 &bpf_tracing_link_lops, prog); 2765 link->attach_type = prog->expected_attach_type; 2766 2767 mutex_lock(&prog->aux->dst_mutex); 2768 2769 /* There are a few possible cases here: 2770 * 2771 * - if prog->aux->dst_trampoline is set, the program was just loaded 2772 * and not yet attached to anything, so we can use the values stored 2773 * in prog->aux 2774 * 2775 * - if prog->aux->dst_trampoline is NULL, the program has already been 2776 * attached to a target and its initial target was cleared (below) 2777 * 2778 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 2779 * target_btf_id using the link_create API. 2780 * 2781 * - if tgt_prog == NULL when this function was called using the old 2782 * raw_tracepoint_open API, and we need a target from prog->aux 2783 * 2784 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 2785 * was detached and is going for re-attachment. 2786 */ 2787 if (!prog->aux->dst_trampoline && !tgt_prog) { 2788 /* 2789 * Allow re-attach for TRACING and LSM programs. If it's 2790 * currently linked, bpf_trampoline_link_prog will fail. 2791 * EXT programs need to specify tgt_prog_fd, so they 2792 * re-attach in separate code path. 2793 */ 2794 if (prog->type != BPF_PROG_TYPE_TRACING && 2795 prog->type != BPF_PROG_TYPE_LSM) { 2796 err = -EINVAL; 2797 goto out_unlock; 2798 } 2799 btf_id = prog->aux->attach_btf_id; 2800 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 2801 } 2802 2803 if (!prog->aux->dst_trampoline || 2804 (key && key != prog->aux->dst_trampoline->key)) { 2805 /* If there is no saved target, or the specified target is 2806 * different from the destination specified at load time, we 2807 * need a new trampoline and a check for compatibility 2808 */ 2809 struct bpf_attach_target_info tgt_info = {}; 2810 2811 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 2812 &tgt_info); 2813 if (err) 2814 goto out_unlock; 2815 2816 tr = bpf_trampoline_get(key, &tgt_info); 2817 if (!tr) { 2818 err = -ENOMEM; 2819 goto out_unlock; 2820 } 2821 } else { 2822 /* The caller didn't specify a target, or the target was the 2823 * same as the destination supplied during program load. This 2824 * means we can reuse the trampoline and reference from program 2825 * load time, and there is no need to allocate a new one. This 2826 * can only happen once for any program, as the saved values in 2827 * prog->aux are cleared below. 2828 */ 2829 tr = prog->aux->dst_trampoline; 2830 tgt_prog = prog->aux->dst_prog; 2831 } 2832 2833 err = bpf_link_prime(&link->link, &link_primer); 2834 if (err) 2835 goto out_unlock; 2836 2837 err = bpf_trampoline_link_prog(prog, tr); 2838 if (err) { 2839 bpf_link_cleanup(&link_primer); 2840 link = NULL; 2841 goto out_unlock; 2842 } 2843 2844 link->tgt_prog = tgt_prog; 2845 link->trampoline = tr; 2846 2847 /* Always clear the trampoline and target prog from prog->aux to make 2848 * sure the original attach destination is not kept alive after a 2849 * program is (re-)attached to another target. 2850 */ 2851 if (prog->aux->dst_prog && 2852 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 2853 /* got extra prog ref from syscall, or attaching to different prog */ 2854 bpf_prog_put(prog->aux->dst_prog); 2855 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 2856 /* we allocated a new trampoline, so free the old one */ 2857 bpf_trampoline_put(prog->aux->dst_trampoline); 2858 2859 prog->aux->dst_prog = NULL; 2860 prog->aux->dst_trampoline = NULL; 2861 mutex_unlock(&prog->aux->dst_mutex); 2862 2863 return bpf_link_settle(&link_primer); 2864 out_unlock: 2865 if (tr && tr != prog->aux->dst_trampoline) 2866 bpf_trampoline_put(tr); 2867 mutex_unlock(&prog->aux->dst_mutex); 2868 kfree(link); 2869 out_put_prog: 2870 if (tgt_prog_fd && tgt_prog) 2871 bpf_prog_put(tgt_prog); 2872 return err; 2873 } 2874 2875 struct bpf_raw_tp_link { 2876 struct bpf_link link; 2877 struct bpf_raw_event_map *btp; 2878 }; 2879 2880 static void bpf_raw_tp_link_release(struct bpf_link *link) 2881 { 2882 struct bpf_raw_tp_link *raw_tp = 2883 container_of(link, struct bpf_raw_tp_link, link); 2884 2885 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2886 bpf_put_raw_tracepoint(raw_tp->btp); 2887 } 2888 2889 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2890 { 2891 struct bpf_raw_tp_link *raw_tp = 2892 container_of(link, struct bpf_raw_tp_link, link); 2893 2894 kfree(raw_tp); 2895 } 2896 2897 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 2898 struct seq_file *seq) 2899 { 2900 struct bpf_raw_tp_link *raw_tp_link = 2901 container_of(link, struct bpf_raw_tp_link, link); 2902 2903 seq_printf(seq, 2904 "tp_name:\t%s\n", 2905 raw_tp_link->btp->tp->name); 2906 } 2907 2908 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 2909 struct bpf_link_info *info) 2910 { 2911 struct bpf_raw_tp_link *raw_tp_link = 2912 container_of(link, struct bpf_raw_tp_link, link); 2913 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 2914 const char *tp_name = raw_tp_link->btp->tp->name; 2915 u32 ulen = info->raw_tracepoint.tp_name_len; 2916 size_t tp_len = strlen(tp_name); 2917 2918 if (!ulen ^ !ubuf) 2919 return -EINVAL; 2920 2921 info->raw_tracepoint.tp_name_len = tp_len + 1; 2922 2923 if (!ubuf) 2924 return 0; 2925 2926 if (ulen >= tp_len + 1) { 2927 if (copy_to_user(ubuf, tp_name, tp_len + 1)) 2928 return -EFAULT; 2929 } else { 2930 char zero = '\0'; 2931 2932 if (copy_to_user(ubuf, tp_name, ulen - 1)) 2933 return -EFAULT; 2934 if (put_user(zero, ubuf + ulen - 1)) 2935 return -EFAULT; 2936 return -ENOSPC; 2937 } 2938 2939 return 0; 2940 } 2941 2942 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 2943 .release = bpf_raw_tp_link_release, 2944 .dealloc = bpf_raw_tp_link_dealloc, 2945 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 2946 .fill_link_info = bpf_raw_tp_link_fill_link_info, 2947 }; 2948 2949 #ifdef CONFIG_PERF_EVENTS 2950 struct bpf_perf_link { 2951 struct bpf_link link; 2952 struct file *perf_file; 2953 }; 2954 2955 static void bpf_perf_link_release(struct bpf_link *link) 2956 { 2957 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2958 struct perf_event *event = perf_link->perf_file->private_data; 2959 2960 perf_event_free_bpf_prog(event); 2961 fput(perf_link->perf_file); 2962 } 2963 2964 static void bpf_perf_link_dealloc(struct bpf_link *link) 2965 { 2966 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2967 2968 kfree(perf_link); 2969 } 2970 2971 static const struct bpf_link_ops bpf_perf_link_lops = { 2972 .release = bpf_perf_link_release, 2973 .dealloc = bpf_perf_link_dealloc, 2974 }; 2975 2976 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 2977 { 2978 struct bpf_link_primer link_primer; 2979 struct bpf_perf_link *link; 2980 struct perf_event *event; 2981 struct file *perf_file; 2982 int err; 2983 2984 if (attr->link_create.flags) 2985 return -EINVAL; 2986 2987 perf_file = perf_event_get(attr->link_create.target_fd); 2988 if (IS_ERR(perf_file)) 2989 return PTR_ERR(perf_file); 2990 2991 link = kzalloc(sizeof(*link), GFP_USER); 2992 if (!link) { 2993 err = -ENOMEM; 2994 goto out_put_file; 2995 } 2996 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 2997 link->perf_file = perf_file; 2998 2999 err = bpf_link_prime(&link->link, &link_primer); 3000 if (err) { 3001 kfree(link); 3002 goto out_put_file; 3003 } 3004 3005 event = perf_file->private_data; 3006 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3007 if (err) { 3008 bpf_link_cleanup(&link_primer); 3009 goto out_put_file; 3010 } 3011 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3012 bpf_prog_inc(prog); 3013 3014 return bpf_link_settle(&link_primer); 3015 3016 out_put_file: 3017 fput(perf_file); 3018 return err; 3019 } 3020 #endif /* CONFIG_PERF_EVENTS */ 3021 3022 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 3023 3024 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3025 { 3026 struct bpf_link_primer link_primer; 3027 struct bpf_raw_tp_link *link; 3028 struct bpf_raw_event_map *btp; 3029 struct bpf_prog *prog; 3030 const char *tp_name; 3031 char buf[128]; 3032 int err; 3033 3034 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3035 return -EINVAL; 3036 3037 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3038 if (IS_ERR(prog)) 3039 return PTR_ERR(prog); 3040 3041 switch (prog->type) { 3042 case BPF_PROG_TYPE_TRACING: 3043 case BPF_PROG_TYPE_EXT: 3044 case BPF_PROG_TYPE_LSM: 3045 if (attr->raw_tracepoint.name) { 3046 /* The attach point for this category of programs 3047 * should be specified via btf_id during program load. 3048 */ 3049 err = -EINVAL; 3050 goto out_put_prog; 3051 } 3052 if (prog->type == BPF_PROG_TYPE_TRACING && 3053 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3054 tp_name = prog->aux->attach_func_name; 3055 break; 3056 } 3057 err = bpf_tracing_prog_attach(prog, 0, 0); 3058 if (err >= 0) 3059 return err; 3060 goto out_put_prog; 3061 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3062 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3063 if (strncpy_from_user(buf, 3064 u64_to_user_ptr(attr->raw_tracepoint.name), 3065 sizeof(buf) - 1) < 0) { 3066 err = -EFAULT; 3067 goto out_put_prog; 3068 } 3069 buf[sizeof(buf) - 1] = 0; 3070 tp_name = buf; 3071 break; 3072 default: 3073 err = -EINVAL; 3074 goto out_put_prog; 3075 } 3076 3077 btp = bpf_get_raw_tracepoint(tp_name); 3078 if (!btp) { 3079 err = -ENOENT; 3080 goto out_put_prog; 3081 } 3082 3083 link = kzalloc(sizeof(*link), GFP_USER); 3084 if (!link) { 3085 err = -ENOMEM; 3086 goto out_put_btp; 3087 } 3088 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3089 &bpf_raw_tp_link_lops, prog); 3090 link->btp = btp; 3091 3092 err = bpf_link_prime(&link->link, &link_primer); 3093 if (err) { 3094 kfree(link); 3095 goto out_put_btp; 3096 } 3097 3098 err = bpf_probe_register(link->btp, prog); 3099 if (err) { 3100 bpf_link_cleanup(&link_primer); 3101 goto out_put_btp; 3102 } 3103 3104 return bpf_link_settle(&link_primer); 3105 3106 out_put_btp: 3107 bpf_put_raw_tracepoint(btp); 3108 out_put_prog: 3109 bpf_prog_put(prog); 3110 return err; 3111 } 3112 3113 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3114 enum bpf_attach_type attach_type) 3115 { 3116 switch (prog->type) { 3117 case BPF_PROG_TYPE_CGROUP_SOCK: 3118 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3119 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3120 case BPF_PROG_TYPE_SK_LOOKUP: 3121 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3122 case BPF_PROG_TYPE_CGROUP_SKB: 3123 if (!capable(CAP_NET_ADMIN)) 3124 /* cg-skb progs can be loaded by unpriv user. 3125 * check permissions at attach time. 3126 */ 3127 return -EPERM; 3128 return prog->enforce_expected_attach_type && 3129 prog->expected_attach_type != attach_type ? 3130 -EINVAL : 0; 3131 default: 3132 return 0; 3133 } 3134 } 3135 3136 static enum bpf_prog_type 3137 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3138 { 3139 switch (attach_type) { 3140 case BPF_CGROUP_INET_INGRESS: 3141 case BPF_CGROUP_INET_EGRESS: 3142 return BPF_PROG_TYPE_CGROUP_SKB; 3143 case BPF_CGROUP_INET_SOCK_CREATE: 3144 case BPF_CGROUP_INET_SOCK_RELEASE: 3145 case BPF_CGROUP_INET4_POST_BIND: 3146 case BPF_CGROUP_INET6_POST_BIND: 3147 return BPF_PROG_TYPE_CGROUP_SOCK; 3148 case BPF_CGROUP_INET4_BIND: 3149 case BPF_CGROUP_INET6_BIND: 3150 case BPF_CGROUP_INET4_CONNECT: 3151 case BPF_CGROUP_INET6_CONNECT: 3152 case BPF_CGROUP_INET4_GETPEERNAME: 3153 case BPF_CGROUP_INET6_GETPEERNAME: 3154 case BPF_CGROUP_INET4_GETSOCKNAME: 3155 case BPF_CGROUP_INET6_GETSOCKNAME: 3156 case BPF_CGROUP_UDP4_SENDMSG: 3157 case BPF_CGROUP_UDP6_SENDMSG: 3158 case BPF_CGROUP_UDP4_RECVMSG: 3159 case BPF_CGROUP_UDP6_RECVMSG: 3160 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3161 case BPF_CGROUP_SOCK_OPS: 3162 return BPF_PROG_TYPE_SOCK_OPS; 3163 case BPF_CGROUP_DEVICE: 3164 return BPF_PROG_TYPE_CGROUP_DEVICE; 3165 case BPF_SK_MSG_VERDICT: 3166 return BPF_PROG_TYPE_SK_MSG; 3167 case BPF_SK_SKB_STREAM_PARSER: 3168 case BPF_SK_SKB_STREAM_VERDICT: 3169 case BPF_SK_SKB_VERDICT: 3170 return BPF_PROG_TYPE_SK_SKB; 3171 case BPF_LIRC_MODE2: 3172 return BPF_PROG_TYPE_LIRC_MODE2; 3173 case BPF_FLOW_DISSECTOR: 3174 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3175 case BPF_CGROUP_SYSCTL: 3176 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3177 case BPF_CGROUP_GETSOCKOPT: 3178 case BPF_CGROUP_SETSOCKOPT: 3179 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3180 case BPF_TRACE_ITER: 3181 return BPF_PROG_TYPE_TRACING; 3182 case BPF_SK_LOOKUP: 3183 return BPF_PROG_TYPE_SK_LOOKUP; 3184 case BPF_XDP: 3185 return BPF_PROG_TYPE_XDP; 3186 default: 3187 return BPF_PROG_TYPE_UNSPEC; 3188 } 3189 } 3190 3191 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 3192 3193 #define BPF_F_ATTACH_MASK \ 3194 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 3195 3196 static int bpf_prog_attach(const union bpf_attr *attr) 3197 { 3198 enum bpf_prog_type ptype; 3199 struct bpf_prog *prog; 3200 int ret; 3201 3202 if (CHECK_ATTR(BPF_PROG_ATTACH)) 3203 return -EINVAL; 3204 3205 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 3206 return -EINVAL; 3207 3208 ptype = attach_type_to_prog_type(attr->attach_type); 3209 if (ptype == BPF_PROG_TYPE_UNSPEC) 3210 return -EINVAL; 3211 3212 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 3213 if (IS_ERR(prog)) 3214 return PTR_ERR(prog); 3215 3216 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 3217 bpf_prog_put(prog); 3218 return -EINVAL; 3219 } 3220 3221 switch (ptype) { 3222 case BPF_PROG_TYPE_SK_SKB: 3223 case BPF_PROG_TYPE_SK_MSG: 3224 ret = sock_map_get_from_fd(attr, prog); 3225 break; 3226 case BPF_PROG_TYPE_LIRC_MODE2: 3227 ret = lirc_prog_attach(attr, prog); 3228 break; 3229 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3230 ret = netns_bpf_prog_attach(attr, prog); 3231 break; 3232 case BPF_PROG_TYPE_CGROUP_DEVICE: 3233 case BPF_PROG_TYPE_CGROUP_SKB: 3234 case BPF_PROG_TYPE_CGROUP_SOCK: 3235 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3236 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3237 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3238 case BPF_PROG_TYPE_SOCK_OPS: 3239 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 3240 break; 3241 default: 3242 ret = -EINVAL; 3243 } 3244 3245 if (ret) 3246 bpf_prog_put(prog); 3247 return ret; 3248 } 3249 3250 #define BPF_PROG_DETACH_LAST_FIELD attach_type 3251 3252 static int bpf_prog_detach(const union bpf_attr *attr) 3253 { 3254 enum bpf_prog_type ptype; 3255 3256 if (CHECK_ATTR(BPF_PROG_DETACH)) 3257 return -EINVAL; 3258 3259 ptype = attach_type_to_prog_type(attr->attach_type); 3260 3261 switch (ptype) { 3262 case BPF_PROG_TYPE_SK_MSG: 3263 case BPF_PROG_TYPE_SK_SKB: 3264 return sock_map_prog_detach(attr, ptype); 3265 case BPF_PROG_TYPE_LIRC_MODE2: 3266 return lirc_prog_detach(attr); 3267 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3268 return netns_bpf_prog_detach(attr, ptype); 3269 case BPF_PROG_TYPE_CGROUP_DEVICE: 3270 case BPF_PROG_TYPE_CGROUP_SKB: 3271 case BPF_PROG_TYPE_CGROUP_SOCK: 3272 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3273 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3274 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3275 case BPF_PROG_TYPE_SOCK_OPS: 3276 return cgroup_bpf_prog_detach(attr, ptype); 3277 default: 3278 return -EINVAL; 3279 } 3280 } 3281 3282 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 3283 3284 static int bpf_prog_query(const union bpf_attr *attr, 3285 union bpf_attr __user *uattr) 3286 { 3287 if (!capable(CAP_NET_ADMIN)) 3288 return -EPERM; 3289 if (CHECK_ATTR(BPF_PROG_QUERY)) 3290 return -EINVAL; 3291 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 3292 return -EINVAL; 3293 3294 switch (attr->query.attach_type) { 3295 case BPF_CGROUP_INET_INGRESS: 3296 case BPF_CGROUP_INET_EGRESS: 3297 case BPF_CGROUP_INET_SOCK_CREATE: 3298 case BPF_CGROUP_INET_SOCK_RELEASE: 3299 case BPF_CGROUP_INET4_BIND: 3300 case BPF_CGROUP_INET6_BIND: 3301 case BPF_CGROUP_INET4_POST_BIND: 3302 case BPF_CGROUP_INET6_POST_BIND: 3303 case BPF_CGROUP_INET4_CONNECT: 3304 case BPF_CGROUP_INET6_CONNECT: 3305 case BPF_CGROUP_INET4_GETPEERNAME: 3306 case BPF_CGROUP_INET6_GETPEERNAME: 3307 case BPF_CGROUP_INET4_GETSOCKNAME: 3308 case BPF_CGROUP_INET6_GETSOCKNAME: 3309 case BPF_CGROUP_UDP4_SENDMSG: 3310 case BPF_CGROUP_UDP6_SENDMSG: 3311 case BPF_CGROUP_UDP4_RECVMSG: 3312 case BPF_CGROUP_UDP6_RECVMSG: 3313 case BPF_CGROUP_SOCK_OPS: 3314 case BPF_CGROUP_DEVICE: 3315 case BPF_CGROUP_SYSCTL: 3316 case BPF_CGROUP_GETSOCKOPT: 3317 case BPF_CGROUP_SETSOCKOPT: 3318 return cgroup_bpf_prog_query(attr, uattr); 3319 case BPF_LIRC_MODE2: 3320 return lirc_prog_query(attr, uattr); 3321 case BPF_FLOW_DISSECTOR: 3322 case BPF_SK_LOOKUP: 3323 return netns_bpf_prog_query(attr, uattr); 3324 default: 3325 return -EINVAL; 3326 } 3327 } 3328 3329 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu 3330 3331 static int bpf_prog_test_run(const union bpf_attr *attr, 3332 union bpf_attr __user *uattr) 3333 { 3334 struct bpf_prog *prog; 3335 int ret = -ENOTSUPP; 3336 3337 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 3338 return -EINVAL; 3339 3340 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 3341 (!attr->test.ctx_size_in && attr->test.ctx_in)) 3342 return -EINVAL; 3343 3344 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 3345 (!attr->test.ctx_size_out && attr->test.ctx_out)) 3346 return -EINVAL; 3347 3348 prog = bpf_prog_get(attr->test.prog_fd); 3349 if (IS_ERR(prog)) 3350 return PTR_ERR(prog); 3351 3352 if (prog->aux->ops->test_run) 3353 ret = prog->aux->ops->test_run(prog, attr, uattr); 3354 3355 bpf_prog_put(prog); 3356 return ret; 3357 } 3358 3359 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 3360 3361 static int bpf_obj_get_next_id(const union bpf_attr *attr, 3362 union bpf_attr __user *uattr, 3363 struct idr *idr, 3364 spinlock_t *lock) 3365 { 3366 u32 next_id = attr->start_id; 3367 int err = 0; 3368 3369 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 3370 return -EINVAL; 3371 3372 if (!capable(CAP_SYS_ADMIN)) 3373 return -EPERM; 3374 3375 next_id++; 3376 spin_lock_bh(lock); 3377 if (!idr_get_next(idr, &next_id)) 3378 err = -ENOENT; 3379 spin_unlock_bh(lock); 3380 3381 if (!err) 3382 err = put_user(next_id, &uattr->next_id); 3383 3384 return err; 3385 } 3386 3387 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 3388 { 3389 struct bpf_map *map; 3390 3391 spin_lock_bh(&map_idr_lock); 3392 again: 3393 map = idr_get_next(&map_idr, id); 3394 if (map) { 3395 map = __bpf_map_inc_not_zero(map, false); 3396 if (IS_ERR(map)) { 3397 (*id)++; 3398 goto again; 3399 } 3400 } 3401 spin_unlock_bh(&map_idr_lock); 3402 3403 return map; 3404 } 3405 3406 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 3407 { 3408 struct bpf_prog *prog; 3409 3410 spin_lock_bh(&prog_idr_lock); 3411 again: 3412 prog = idr_get_next(&prog_idr, id); 3413 if (prog) { 3414 prog = bpf_prog_inc_not_zero(prog); 3415 if (IS_ERR(prog)) { 3416 (*id)++; 3417 goto again; 3418 } 3419 } 3420 spin_unlock_bh(&prog_idr_lock); 3421 3422 return prog; 3423 } 3424 3425 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 3426 3427 struct bpf_prog *bpf_prog_by_id(u32 id) 3428 { 3429 struct bpf_prog *prog; 3430 3431 if (!id) 3432 return ERR_PTR(-ENOENT); 3433 3434 spin_lock_bh(&prog_idr_lock); 3435 prog = idr_find(&prog_idr, id); 3436 if (prog) 3437 prog = bpf_prog_inc_not_zero(prog); 3438 else 3439 prog = ERR_PTR(-ENOENT); 3440 spin_unlock_bh(&prog_idr_lock); 3441 return prog; 3442 } 3443 3444 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 3445 { 3446 struct bpf_prog *prog; 3447 u32 id = attr->prog_id; 3448 int fd; 3449 3450 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 3451 return -EINVAL; 3452 3453 if (!capable(CAP_SYS_ADMIN)) 3454 return -EPERM; 3455 3456 prog = bpf_prog_by_id(id); 3457 if (IS_ERR(prog)) 3458 return PTR_ERR(prog); 3459 3460 fd = bpf_prog_new_fd(prog); 3461 if (fd < 0) 3462 bpf_prog_put(prog); 3463 3464 return fd; 3465 } 3466 3467 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 3468 3469 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 3470 { 3471 struct bpf_map *map; 3472 u32 id = attr->map_id; 3473 int f_flags; 3474 int fd; 3475 3476 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 3477 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 3478 return -EINVAL; 3479 3480 if (!capable(CAP_SYS_ADMIN)) 3481 return -EPERM; 3482 3483 f_flags = bpf_get_file_flag(attr->open_flags); 3484 if (f_flags < 0) 3485 return f_flags; 3486 3487 spin_lock_bh(&map_idr_lock); 3488 map = idr_find(&map_idr, id); 3489 if (map) 3490 map = __bpf_map_inc_not_zero(map, true); 3491 else 3492 map = ERR_PTR(-ENOENT); 3493 spin_unlock_bh(&map_idr_lock); 3494 3495 if (IS_ERR(map)) 3496 return PTR_ERR(map); 3497 3498 fd = bpf_map_new_fd(map, f_flags); 3499 if (fd < 0) 3500 bpf_map_put_with_uref(map); 3501 3502 return fd; 3503 } 3504 3505 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 3506 unsigned long addr, u32 *off, 3507 u32 *type) 3508 { 3509 const struct bpf_map *map; 3510 int i; 3511 3512 mutex_lock(&prog->aux->used_maps_mutex); 3513 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 3514 map = prog->aux->used_maps[i]; 3515 if (map == (void *)addr) { 3516 *type = BPF_PSEUDO_MAP_FD; 3517 goto out; 3518 } 3519 if (!map->ops->map_direct_value_meta) 3520 continue; 3521 if (!map->ops->map_direct_value_meta(map, addr, off)) { 3522 *type = BPF_PSEUDO_MAP_VALUE; 3523 goto out; 3524 } 3525 } 3526 map = NULL; 3527 3528 out: 3529 mutex_unlock(&prog->aux->used_maps_mutex); 3530 return map; 3531 } 3532 3533 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 3534 const struct cred *f_cred) 3535 { 3536 const struct bpf_map *map; 3537 struct bpf_insn *insns; 3538 u32 off, type; 3539 u64 imm; 3540 u8 code; 3541 int i; 3542 3543 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 3544 GFP_USER); 3545 if (!insns) 3546 return insns; 3547 3548 for (i = 0; i < prog->len; i++) { 3549 code = insns[i].code; 3550 3551 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 3552 insns[i].code = BPF_JMP | BPF_CALL; 3553 insns[i].imm = BPF_FUNC_tail_call; 3554 /* fall-through */ 3555 } 3556 if (code == (BPF_JMP | BPF_CALL) || 3557 code == (BPF_JMP | BPF_CALL_ARGS)) { 3558 if (code == (BPF_JMP | BPF_CALL_ARGS)) 3559 insns[i].code = BPF_JMP | BPF_CALL; 3560 if (!bpf_dump_raw_ok(f_cred)) 3561 insns[i].imm = 0; 3562 continue; 3563 } 3564 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 3565 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 3566 continue; 3567 } 3568 3569 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 3570 continue; 3571 3572 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 3573 map = bpf_map_from_imm(prog, imm, &off, &type); 3574 if (map) { 3575 insns[i].src_reg = type; 3576 insns[i].imm = map->id; 3577 insns[i + 1].imm = off; 3578 continue; 3579 } 3580 } 3581 3582 return insns; 3583 } 3584 3585 static int set_info_rec_size(struct bpf_prog_info *info) 3586 { 3587 /* 3588 * Ensure info.*_rec_size is the same as kernel expected size 3589 * 3590 * or 3591 * 3592 * Only allow zero *_rec_size if both _rec_size and _cnt are 3593 * zero. In this case, the kernel will set the expected 3594 * _rec_size back to the info. 3595 */ 3596 3597 if ((info->nr_func_info || info->func_info_rec_size) && 3598 info->func_info_rec_size != sizeof(struct bpf_func_info)) 3599 return -EINVAL; 3600 3601 if ((info->nr_line_info || info->line_info_rec_size) && 3602 info->line_info_rec_size != sizeof(struct bpf_line_info)) 3603 return -EINVAL; 3604 3605 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 3606 info->jited_line_info_rec_size != sizeof(__u64)) 3607 return -EINVAL; 3608 3609 info->func_info_rec_size = sizeof(struct bpf_func_info); 3610 info->line_info_rec_size = sizeof(struct bpf_line_info); 3611 info->jited_line_info_rec_size = sizeof(__u64); 3612 3613 return 0; 3614 } 3615 3616 static int bpf_prog_get_info_by_fd(struct file *file, 3617 struct bpf_prog *prog, 3618 const union bpf_attr *attr, 3619 union bpf_attr __user *uattr) 3620 { 3621 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3622 struct bpf_prog_info info; 3623 u32 info_len = attr->info.info_len; 3624 struct bpf_prog_kstats stats; 3625 char __user *uinsns; 3626 u32 ulen; 3627 int err; 3628 3629 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3630 if (err) 3631 return err; 3632 info_len = min_t(u32, sizeof(info), info_len); 3633 3634 memset(&info, 0, sizeof(info)); 3635 if (copy_from_user(&info, uinfo, info_len)) 3636 return -EFAULT; 3637 3638 info.type = prog->type; 3639 info.id = prog->aux->id; 3640 info.load_time = prog->aux->load_time; 3641 info.created_by_uid = from_kuid_munged(current_user_ns(), 3642 prog->aux->user->uid); 3643 info.gpl_compatible = prog->gpl_compatible; 3644 3645 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3646 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3647 3648 mutex_lock(&prog->aux->used_maps_mutex); 3649 ulen = info.nr_map_ids; 3650 info.nr_map_ids = prog->aux->used_map_cnt; 3651 ulen = min_t(u32, info.nr_map_ids, ulen); 3652 if (ulen) { 3653 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3654 u32 i; 3655 3656 for (i = 0; i < ulen; i++) 3657 if (put_user(prog->aux->used_maps[i]->id, 3658 &user_map_ids[i])) { 3659 mutex_unlock(&prog->aux->used_maps_mutex); 3660 return -EFAULT; 3661 } 3662 } 3663 mutex_unlock(&prog->aux->used_maps_mutex); 3664 3665 err = set_info_rec_size(&info); 3666 if (err) 3667 return err; 3668 3669 bpf_prog_get_stats(prog, &stats); 3670 info.run_time_ns = stats.nsecs; 3671 info.run_cnt = stats.cnt; 3672 info.recursion_misses = stats.misses; 3673 3674 info.verified_insns = prog->aux->verified_insns; 3675 3676 if (!bpf_capable()) { 3677 info.jited_prog_len = 0; 3678 info.xlated_prog_len = 0; 3679 info.nr_jited_ksyms = 0; 3680 info.nr_jited_func_lens = 0; 3681 info.nr_func_info = 0; 3682 info.nr_line_info = 0; 3683 info.nr_jited_line_info = 0; 3684 goto done; 3685 } 3686 3687 ulen = info.xlated_prog_len; 3688 info.xlated_prog_len = bpf_prog_insn_size(prog); 3689 if (info.xlated_prog_len && ulen) { 3690 struct bpf_insn *insns_sanitized; 3691 bool fault; 3692 3693 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 3694 info.xlated_prog_insns = 0; 3695 goto done; 3696 } 3697 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 3698 if (!insns_sanitized) 3699 return -ENOMEM; 3700 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3701 ulen = min_t(u32, info.xlated_prog_len, ulen); 3702 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3703 kfree(insns_sanitized); 3704 if (fault) 3705 return -EFAULT; 3706 } 3707 3708 if (bpf_prog_is_dev_bound(prog->aux)) { 3709 err = bpf_prog_offload_info_fill(&info, prog); 3710 if (err) 3711 return err; 3712 goto done; 3713 } 3714 3715 /* NOTE: the following code is supposed to be skipped for offload. 3716 * bpf_prog_offload_info_fill() is the place to fill similar fields 3717 * for offload. 3718 */ 3719 ulen = info.jited_prog_len; 3720 if (prog->aux->func_cnt) { 3721 u32 i; 3722 3723 info.jited_prog_len = 0; 3724 for (i = 0; i < prog->aux->func_cnt; i++) 3725 info.jited_prog_len += prog->aux->func[i]->jited_len; 3726 } else { 3727 info.jited_prog_len = prog->jited_len; 3728 } 3729 3730 if (info.jited_prog_len && ulen) { 3731 if (bpf_dump_raw_ok(file->f_cred)) { 3732 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3733 ulen = min_t(u32, info.jited_prog_len, ulen); 3734 3735 /* for multi-function programs, copy the JITed 3736 * instructions for all the functions 3737 */ 3738 if (prog->aux->func_cnt) { 3739 u32 len, free, i; 3740 u8 *img; 3741 3742 free = ulen; 3743 for (i = 0; i < prog->aux->func_cnt; i++) { 3744 len = prog->aux->func[i]->jited_len; 3745 len = min_t(u32, len, free); 3746 img = (u8 *) prog->aux->func[i]->bpf_func; 3747 if (copy_to_user(uinsns, img, len)) 3748 return -EFAULT; 3749 uinsns += len; 3750 free -= len; 3751 if (!free) 3752 break; 3753 } 3754 } else { 3755 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3756 return -EFAULT; 3757 } 3758 } else { 3759 info.jited_prog_insns = 0; 3760 } 3761 } 3762 3763 ulen = info.nr_jited_ksyms; 3764 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3765 if (ulen) { 3766 if (bpf_dump_raw_ok(file->f_cred)) { 3767 unsigned long ksym_addr; 3768 u64 __user *user_ksyms; 3769 u32 i; 3770 3771 /* copy the address of the kernel symbol 3772 * corresponding to each function 3773 */ 3774 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3775 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3776 if (prog->aux->func_cnt) { 3777 for (i = 0; i < ulen; i++) { 3778 ksym_addr = (unsigned long) 3779 prog->aux->func[i]->bpf_func; 3780 if (put_user((u64) ksym_addr, 3781 &user_ksyms[i])) 3782 return -EFAULT; 3783 } 3784 } else { 3785 ksym_addr = (unsigned long) prog->bpf_func; 3786 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3787 return -EFAULT; 3788 } 3789 } else { 3790 info.jited_ksyms = 0; 3791 } 3792 } 3793 3794 ulen = info.nr_jited_func_lens; 3795 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3796 if (ulen) { 3797 if (bpf_dump_raw_ok(file->f_cred)) { 3798 u32 __user *user_lens; 3799 u32 func_len, i; 3800 3801 /* copy the JITed image lengths for each function */ 3802 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3803 user_lens = u64_to_user_ptr(info.jited_func_lens); 3804 if (prog->aux->func_cnt) { 3805 for (i = 0; i < ulen; i++) { 3806 func_len = 3807 prog->aux->func[i]->jited_len; 3808 if (put_user(func_len, &user_lens[i])) 3809 return -EFAULT; 3810 } 3811 } else { 3812 func_len = prog->jited_len; 3813 if (put_user(func_len, &user_lens[0])) 3814 return -EFAULT; 3815 } 3816 } else { 3817 info.jited_func_lens = 0; 3818 } 3819 } 3820 3821 if (prog->aux->btf) 3822 info.btf_id = btf_obj_id(prog->aux->btf); 3823 3824 ulen = info.nr_func_info; 3825 info.nr_func_info = prog->aux->func_info_cnt; 3826 if (info.nr_func_info && ulen) { 3827 char __user *user_finfo; 3828 3829 user_finfo = u64_to_user_ptr(info.func_info); 3830 ulen = min_t(u32, info.nr_func_info, ulen); 3831 if (copy_to_user(user_finfo, prog->aux->func_info, 3832 info.func_info_rec_size * ulen)) 3833 return -EFAULT; 3834 } 3835 3836 ulen = info.nr_line_info; 3837 info.nr_line_info = prog->aux->nr_linfo; 3838 if (info.nr_line_info && ulen) { 3839 __u8 __user *user_linfo; 3840 3841 user_linfo = u64_to_user_ptr(info.line_info); 3842 ulen = min_t(u32, info.nr_line_info, ulen); 3843 if (copy_to_user(user_linfo, prog->aux->linfo, 3844 info.line_info_rec_size * ulen)) 3845 return -EFAULT; 3846 } 3847 3848 ulen = info.nr_jited_line_info; 3849 if (prog->aux->jited_linfo) 3850 info.nr_jited_line_info = prog->aux->nr_linfo; 3851 else 3852 info.nr_jited_line_info = 0; 3853 if (info.nr_jited_line_info && ulen) { 3854 if (bpf_dump_raw_ok(file->f_cred)) { 3855 __u64 __user *user_linfo; 3856 u32 i; 3857 3858 user_linfo = u64_to_user_ptr(info.jited_line_info); 3859 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3860 for (i = 0; i < ulen; i++) { 3861 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3862 &user_linfo[i])) 3863 return -EFAULT; 3864 } 3865 } else { 3866 info.jited_line_info = 0; 3867 } 3868 } 3869 3870 ulen = info.nr_prog_tags; 3871 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3872 if (ulen) { 3873 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3874 u32 i; 3875 3876 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3877 ulen = min_t(u32, info.nr_prog_tags, ulen); 3878 if (prog->aux->func_cnt) { 3879 for (i = 0; i < ulen; i++) { 3880 if (copy_to_user(user_prog_tags[i], 3881 prog->aux->func[i]->tag, 3882 BPF_TAG_SIZE)) 3883 return -EFAULT; 3884 } 3885 } else { 3886 if (copy_to_user(user_prog_tags[0], 3887 prog->tag, BPF_TAG_SIZE)) 3888 return -EFAULT; 3889 } 3890 } 3891 3892 done: 3893 if (copy_to_user(uinfo, &info, info_len) || 3894 put_user(info_len, &uattr->info.info_len)) 3895 return -EFAULT; 3896 3897 return 0; 3898 } 3899 3900 static int bpf_map_get_info_by_fd(struct file *file, 3901 struct bpf_map *map, 3902 const union bpf_attr *attr, 3903 union bpf_attr __user *uattr) 3904 { 3905 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3906 struct bpf_map_info info; 3907 u32 info_len = attr->info.info_len; 3908 int err; 3909 3910 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3911 if (err) 3912 return err; 3913 info_len = min_t(u32, sizeof(info), info_len); 3914 3915 memset(&info, 0, sizeof(info)); 3916 info.type = map->map_type; 3917 info.id = map->id; 3918 info.key_size = map->key_size; 3919 info.value_size = map->value_size; 3920 info.max_entries = map->max_entries; 3921 info.map_flags = map->map_flags; 3922 info.map_extra = map->map_extra; 3923 memcpy(info.name, map->name, sizeof(map->name)); 3924 3925 if (map->btf) { 3926 info.btf_id = btf_obj_id(map->btf); 3927 info.btf_key_type_id = map->btf_key_type_id; 3928 info.btf_value_type_id = map->btf_value_type_id; 3929 } 3930 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3931 3932 if (bpf_map_is_dev_bound(map)) { 3933 err = bpf_map_offload_info_fill(&info, map); 3934 if (err) 3935 return err; 3936 } 3937 3938 if (copy_to_user(uinfo, &info, info_len) || 3939 put_user(info_len, &uattr->info.info_len)) 3940 return -EFAULT; 3941 3942 return 0; 3943 } 3944 3945 static int bpf_btf_get_info_by_fd(struct file *file, 3946 struct btf *btf, 3947 const union bpf_attr *attr, 3948 union bpf_attr __user *uattr) 3949 { 3950 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3951 u32 info_len = attr->info.info_len; 3952 int err; 3953 3954 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 3955 if (err) 3956 return err; 3957 3958 return btf_get_info_by_fd(btf, attr, uattr); 3959 } 3960 3961 static int bpf_link_get_info_by_fd(struct file *file, 3962 struct bpf_link *link, 3963 const union bpf_attr *attr, 3964 union bpf_attr __user *uattr) 3965 { 3966 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3967 struct bpf_link_info info; 3968 u32 info_len = attr->info.info_len; 3969 int err; 3970 3971 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3972 if (err) 3973 return err; 3974 info_len = min_t(u32, sizeof(info), info_len); 3975 3976 memset(&info, 0, sizeof(info)); 3977 if (copy_from_user(&info, uinfo, info_len)) 3978 return -EFAULT; 3979 3980 info.type = link->type; 3981 info.id = link->id; 3982 info.prog_id = link->prog->aux->id; 3983 3984 if (link->ops->fill_link_info) { 3985 err = link->ops->fill_link_info(link, &info); 3986 if (err) 3987 return err; 3988 } 3989 3990 if (copy_to_user(uinfo, &info, info_len) || 3991 put_user(info_len, &uattr->info.info_len)) 3992 return -EFAULT; 3993 3994 return 0; 3995 } 3996 3997 3998 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 3999 4000 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 4001 union bpf_attr __user *uattr) 4002 { 4003 int ufd = attr->info.bpf_fd; 4004 struct fd f; 4005 int err; 4006 4007 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4008 return -EINVAL; 4009 4010 f = fdget(ufd); 4011 if (!f.file) 4012 return -EBADFD; 4013 4014 if (f.file->f_op == &bpf_prog_fops) 4015 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr, 4016 uattr); 4017 else if (f.file->f_op == &bpf_map_fops) 4018 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr, 4019 uattr); 4020 else if (f.file->f_op == &btf_fops) 4021 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr); 4022 else if (f.file->f_op == &bpf_link_fops) 4023 err = bpf_link_get_info_by_fd(f.file, f.file->private_data, 4024 attr, uattr); 4025 else 4026 err = -EINVAL; 4027 4028 fdput(f); 4029 return err; 4030 } 4031 4032 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 4033 4034 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr) 4035 { 4036 if (CHECK_ATTR(BPF_BTF_LOAD)) 4037 return -EINVAL; 4038 4039 if (!bpf_capable()) 4040 return -EPERM; 4041 4042 return btf_new_fd(attr, uattr); 4043 } 4044 4045 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4046 4047 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4048 { 4049 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4050 return -EINVAL; 4051 4052 if (!capable(CAP_SYS_ADMIN)) 4053 return -EPERM; 4054 4055 return btf_get_fd_by_id(attr->btf_id); 4056 } 4057 4058 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 4059 union bpf_attr __user *uattr, 4060 u32 prog_id, u32 fd_type, 4061 const char *buf, u64 probe_offset, 4062 u64 probe_addr) 4063 { 4064 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 4065 u32 len = buf ? strlen(buf) : 0, input_len; 4066 int err = 0; 4067 4068 if (put_user(len, &uattr->task_fd_query.buf_len)) 4069 return -EFAULT; 4070 input_len = attr->task_fd_query.buf_len; 4071 if (input_len && ubuf) { 4072 if (!len) { 4073 /* nothing to copy, just make ubuf NULL terminated */ 4074 char zero = '\0'; 4075 4076 if (put_user(zero, ubuf)) 4077 return -EFAULT; 4078 } else if (input_len >= len + 1) { 4079 /* ubuf can hold the string with NULL terminator */ 4080 if (copy_to_user(ubuf, buf, len + 1)) 4081 return -EFAULT; 4082 } else { 4083 /* ubuf cannot hold the string with NULL terminator, 4084 * do a partial copy with NULL terminator. 4085 */ 4086 char zero = '\0'; 4087 4088 err = -ENOSPC; 4089 if (copy_to_user(ubuf, buf, input_len - 1)) 4090 return -EFAULT; 4091 if (put_user(zero, ubuf + input_len - 1)) 4092 return -EFAULT; 4093 } 4094 } 4095 4096 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 4097 put_user(fd_type, &uattr->task_fd_query.fd_type) || 4098 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 4099 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 4100 return -EFAULT; 4101 4102 return err; 4103 } 4104 4105 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 4106 4107 static int bpf_task_fd_query(const union bpf_attr *attr, 4108 union bpf_attr __user *uattr) 4109 { 4110 pid_t pid = attr->task_fd_query.pid; 4111 u32 fd = attr->task_fd_query.fd; 4112 const struct perf_event *event; 4113 struct task_struct *task; 4114 struct file *file; 4115 int err; 4116 4117 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 4118 return -EINVAL; 4119 4120 if (!capable(CAP_SYS_ADMIN)) 4121 return -EPERM; 4122 4123 if (attr->task_fd_query.flags != 0) 4124 return -EINVAL; 4125 4126 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 4127 if (!task) 4128 return -ENOENT; 4129 4130 err = 0; 4131 file = fget_task(task, fd); 4132 put_task_struct(task); 4133 if (!file) 4134 return -EBADF; 4135 4136 if (file->f_op == &bpf_link_fops) { 4137 struct bpf_link *link = file->private_data; 4138 4139 if (link->ops == &bpf_raw_tp_link_lops) { 4140 struct bpf_raw_tp_link *raw_tp = 4141 container_of(link, struct bpf_raw_tp_link, link); 4142 struct bpf_raw_event_map *btp = raw_tp->btp; 4143 4144 err = bpf_task_fd_query_copy(attr, uattr, 4145 raw_tp->link.prog->aux->id, 4146 BPF_FD_TYPE_RAW_TRACEPOINT, 4147 btp->tp->name, 0, 0); 4148 goto put_file; 4149 } 4150 goto out_not_supp; 4151 } 4152 4153 event = perf_get_event(file); 4154 if (!IS_ERR(event)) { 4155 u64 probe_offset, probe_addr; 4156 u32 prog_id, fd_type; 4157 const char *buf; 4158 4159 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 4160 &buf, &probe_offset, 4161 &probe_addr); 4162 if (!err) 4163 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 4164 fd_type, buf, 4165 probe_offset, 4166 probe_addr); 4167 goto put_file; 4168 } 4169 4170 out_not_supp: 4171 err = -ENOTSUPP; 4172 put_file: 4173 fput(file); 4174 return err; 4175 } 4176 4177 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 4178 4179 #define BPF_DO_BATCH(fn) \ 4180 do { \ 4181 if (!fn) { \ 4182 err = -ENOTSUPP; \ 4183 goto err_put; \ 4184 } \ 4185 err = fn(map, attr, uattr); \ 4186 } while (0) 4187 4188 static int bpf_map_do_batch(const union bpf_attr *attr, 4189 union bpf_attr __user *uattr, 4190 int cmd) 4191 { 4192 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 4193 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 4194 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 4195 struct bpf_map *map; 4196 int err, ufd; 4197 struct fd f; 4198 4199 if (CHECK_ATTR(BPF_MAP_BATCH)) 4200 return -EINVAL; 4201 4202 ufd = attr->batch.map_fd; 4203 f = fdget(ufd); 4204 map = __bpf_map_get(f); 4205 if (IS_ERR(map)) 4206 return PTR_ERR(map); 4207 if (has_write) 4208 bpf_map_write_active_inc(map); 4209 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 4210 err = -EPERM; 4211 goto err_put; 4212 } 4213 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 4214 err = -EPERM; 4215 goto err_put; 4216 } 4217 4218 if (cmd == BPF_MAP_LOOKUP_BATCH) 4219 BPF_DO_BATCH(map->ops->map_lookup_batch); 4220 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 4221 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 4222 else if (cmd == BPF_MAP_UPDATE_BATCH) 4223 BPF_DO_BATCH(map->ops->map_update_batch); 4224 else 4225 BPF_DO_BATCH(map->ops->map_delete_batch); 4226 err_put: 4227 if (has_write) 4228 bpf_map_write_active_dec(map); 4229 fdput(f); 4230 return err; 4231 } 4232 4233 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, 4234 struct bpf_prog *prog) 4235 { 4236 if (attr->link_create.attach_type != prog->expected_attach_type) 4237 return -EINVAL; 4238 4239 if (prog->expected_attach_type == BPF_TRACE_ITER) 4240 return bpf_iter_link_attach(attr, uattr, prog); 4241 else if (prog->type == BPF_PROG_TYPE_EXT) 4242 return bpf_tracing_prog_attach(prog, 4243 attr->link_create.target_fd, 4244 attr->link_create.target_btf_id); 4245 return -EINVAL; 4246 } 4247 4248 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len 4249 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 4250 { 4251 enum bpf_prog_type ptype; 4252 struct bpf_prog *prog; 4253 int ret; 4254 4255 if (CHECK_ATTR(BPF_LINK_CREATE)) 4256 return -EINVAL; 4257 4258 prog = bpf_prog_get(attr->link_create.prog_fd); 4259 if (IS_ERR(prog)) 4260 return PTR_ERR(prog); 4261 4262 ret = bpf_prog_attach_check_attach_type(prog, 4263 attr->link_create.attach_type); 4264 if (ret) 4265 goto out; 4266 4267 switch (prog->type) { 4268 case BPF_PROG_TYPE_EXT: 4269 ret = tracing_bpf_link_attach(attr, uattr, prog); 4270 goto out; 4271 case BPF_PROG_TYPE_PERF_EVENT: 4272 case BPF_PROG_TYPE_KPROBE: 4273 case BPF_PROG_TYPE_TRACEPOINT: 4274 if (attr->link_create.attach_type != BPF_PERF_EVENT) { 4275 ret = -EINVAL; 4276 goto out; 4277 } 4278 ptype = prog->type; 4279 break; 4280 default: 4281 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 4282 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) { 4283 ret = -EINVAL; 4284 goto out; 4285 } 4286 break; 4287 } 4288 4289 switch (ptype) { 4290 case BPF_PROG_TYPE_CGROUP_SKB: 4291 case BPF_PROG_TYPE_CGROUP_SOCK: 4292 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4293 case BPF_PROG_TYPE_SOCK_OPS: 4294 case BPF_PROG_TYPE_CGROUP_DEVICE: 4295 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4296 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4297 ret = cgroup_bpf_link_attach(attr, prog); 4298 break; 4299 case BPF_PROG_TYPE_TRACING: 4300 ret = tracing_bpf_link_attach(attr, uattr, prog); 4301 break; 4302 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4303 case BPF_PROG_TYPE_SK_LOOKUP: 4304 ret = netns_bpf_link_create(attr, prog); 4305 break; 4306 #ifdef CONFIG_NET 4307 case BPF_PROG_TYPE_XDP: 4308 ret = bpf_xdp_link_attach(attr, prog); 4309 break; 4310 #endif 4311 #ifdef CONFIG_PERF_EVENTS 4312 case BPF_PROG_TYPE_PERF_EVENT: 4313 case BPF_PROG_TYPE_TRACEPOINT: 4314 case BPF_PROG_TYPE_KPROBE: 4315 ret = bpf_perf_link_attach(attr, prog); 4316 break; 4317 #endif 4318 default: 4319 ret = -EINVAL; 4320 } 4321 4322 out: 4323 if (ret < 0) 4324 bpf_prog_put(prog); 4325 return ret; 4326 } 4327 4328 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 4329 4330 static int link_update(union bpf_attr *attr) 4331 { 4332 struct bpf_prog *old_prog = NULL, *new_prog; 4333 struct bpf_link *link; 4334 u32 flags; 4335 int ret; 4336 4337 if (CHECK_ATTR(BPF_LINK_UPDATE)) 4338 return -EINVAL; 4339 4340 flags = attr->link_update.flags; 4341 if (flags & ~BPF_F_REPLACE) 4342 return -EINVAL; 4343 4344 link = bpf_link_get_from_fd(attr->link_update.link_fd); 4345 if (IS_ERR(link)) 4346 return PTR_ERR(link); 4347 4348 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 4349 if (IS_ERR(new_prog)) { 4350 ret = PTR_ERR(new_prog); 4351 goto out_put_link; 4352 } 4353 4354 if (flags & BPF_F_REPLACE) { 4355 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 4356 if (IS_ERR(old_prog)) { 4357 ret = PTR_ERR(old_prog); 4358 old_prog = NULL; 4359 goto out_put_progs; 4360 } 4361 } else if (attr->link_update.old_prog_fd) { 4362 ret = -EINVAL; 4363 goto out_put_progs; 4364 } 4365 4366 if (link->ops->update_prog) 4367 ret = link->ops->update_prog(link, new_prog, old_prog); 4368 else 4369 ret = -EINVAL; 4370 4371 out_put_progs: 4372 if (old_prog) 4373 bpf_prog_put(old_prog); 4374 if (ret) 4375 bpf_prog_put(new_prog); 4376 out_put_link: 4377 bpf_link_put(link); 4378 return ret; 4379 } 4380 4381 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 4382 4383 static int link_detach(union bpf_attr *attr) 4384 { 4385 struct bpf_link *link; 4386 int ret; 4387 4388 if (CHECK_ATTR(BPF_LINK_DETACH)) 4389 return -EINVAL; 4390 4391 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 4392 if (IS_ERR(link)) 4393 return PTR_ERR(link); 4394 4395 if (link->ops->detach) 4396 ret = link->ops->detach(link); 4397 else 4398 ret = -EOPNOTSUPP; 4399 4400 bpf_link_put(link); 4401 return ret; 4402 } 4403 4404 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 4405 { 4406 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 4407 } 4408 4409 struct bpf_link *bpf_link_by_id(u32 id) 4410 { 4411 struct bpf_link *link; 4412 4413 if (!id) 4414 return ERR_PTR(-ENOENT); 4415 4416 spin_lock_bh(&link_idr_lock); 4417 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 4418 link = idr_find(&link_idr, id); 4419 if (link) { 4420 if (link->id) 4421 link = bpf_link_inc_not_zero(link); 4422 else 4423 link = ERR_PTR(-EAGAIN); 4424 } else { 4425 link = ERR_PTR(-ENOENT); 4426 } 4427 spin_unlock_bh(&link_idr_lock); 4428 return link; 4429 } 4430 4431 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 4432 4433 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 4434 { 4435 struct bpf_link *link; 4436 u32 id = attr->link_id; 4437 int fd; 4438 4439 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 4440 return -EINVAL; 4441 4442 if (!capable(CAP_SYS_ADMIN)) 4443 return -EPERM; 4444 4445 link = bpf_link_by_id(id); 4446 if (IS_ERR(link)) 4447 return PTR_ERR(link); 4448 4449 fd = bpf_link_new_fd(link); 4450 if (fd < 0) 4451 bpf_link_put(link); 4452 4453 return fd; 4454 } 4455 4456 DEFINE_MUTEX(bpf_stats_enabled_mutex); 4457 4458 static int bpf_stats_release(struct inode *inode, struct file *file) 4459 { 4460 mutex_lock(&bpf_stats_enabled_mutex); 4461 static_key_slow_dec(&bpf_stats_enabled_key.key); 4462 mutex_unlock(&bpf_stats_enabled_mutex); 4463 return 0; 4464 } 4465 4466 static const struct file_operations bpf_stats_fops = { 4467 .release = bpf_stats_release, 4468 }; 4469 4470 static int bpf_enable_runtime_stats(void) 4471 { 4472 int fd; 4473 4474 mutex_lock(&bpf_stats_enabled_mutex); 4475 4476 /* Set a very high limit to avoid overflow */ 4477 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 4478 mutex_unlock(&bpf_stats_enabled_mutex); 4479 return -EBUSY; 4480 } 4481 4482 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 4483 if (fd >= 0) 4484 static_key_slow_inc(&bpf_stats_enabled_key.key); 4485 4486 mutex_unlock(&bpf_stats_enabled_mutex); 4487 return fd; 4488 } 4489 4490 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 4491 4492 static int bpf_enable_stats(union bpf_attr *attr) 4493 { 4494 4495 if (CHECK_ATTR(BPF_ENABLE_STATS)) 4496 return -EINVAL; 4497 4498 if (!capable(CAP_SYS_ADMIN)) 4499 return -EPERM; 4500 4501 switch (attr->enable_stats.type) { 4502 case BPF_STATS_RUN_TIME: 4503 return bpf_enable_runtime_stats(); 4504 default: 4505 break; 4506 } 4507 return -EINVAL; 4508 } 4509 4510 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 4511 4512 static int bpf_iter_create(union bpf_attr *attr) 4513 { 4514 struct bpf_link *link; 4515 int err; 4516 4517 if (CHECK_ATTR(BPF_ITER_CREATE)) 4518 return -EINVAL; 4519 4520 if (attr->iter_create.flags) 4521 return -EINVAL; 4522 4523 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 4524 if (IS_ERR(link)) 4525 return PTR_ERR(link); 4526 4527 err = bpf_iter_new_fd(link); 4528 bpf_link_put(link); 4529 4530 return err; 4531 } 4532 4533 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 4534 4535 static int bpf_prog_bind_map(union bpf_attr *attr) 4536 { 4537 struct bpf_prog *prog; 4538 struct bpf_map *map; 4539 struct bpf_map **used_maps_old, **used_maps_new; 4540 int i, ret = 0; 4541 4542 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 4543 return -EINVAL; 4544 4545 if (attr->prog_bind_map.flags) 4546 return -EINVAL; 4547 4548 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 4549 if (IS_ERR(prog)) 4550 return PTR_ERR(prog); 4551 4552 map = bpf_map_get(attr->prog_bind_map.map_fd); 4553 if (IS_ERR(map)) { 4554 ret = PTR_ERR(map); 4555 goto out_prog_put; 4556 } 4557 4558 mutex_lock(&prog->aux->used_maps_mutex); 4559 4560 used_maps_old = prog->aux->used_maps; 4561 4562 for (i = 0; i < prog->aux->used_map_cnt; i++) 4563 if (used_maps_old[i] == map) { 4564 bpf_map_put(map); 4565 goto out_unlock; 4566 } 4567 4568 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 4569 sizeof(used_maps_new[0]), 4570 GFP_KERNEL); 4571 if (!used_maps_new) { 4572 ret = -ENOMEM; 4573 goto out_unlock; 4574 } 4575 4576 memcpy(used_maps_new, used_maps_old, 4577 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 4578 used_maps_new[prog->aux->used_map_cnt] = map; 4579 4580 prog->aux->used_map_cnt++; 4581 prog->aux->used_maps = used_maps_new; 4582 4583 kfree(used_maps_old); 4584 4585 out_unlock: 4586 mutex_unlock(&prog->aux->used_maps_mutex); 4587 4588 if (ret) 4589 bpf_map_put(map); 4590 out_prog_put: 4591 bpf_prog_put(prog); 4592 return ret; 4593 } 4594 4595 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) 4596 { 4597 union bpf_attr attr; 4598 int err; 4599 4600 if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) 4601 return -EPERM; 4602 4603 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 4604 if (err) 4605 return err; 4606 size = min_t(u32, size, sizeof(attr)); 4607 4608 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 4609 memset(&attr, 0, sizeof(attr)); 4610 if (copy_from_bpfptr(&attr, uattr, size) != 0) 4611 return -EFAULT; 4612 4613 err = security_bpf(cmd, &attr, size); 4614 if (err < 0) 4615 return err; 4616 4617 switch (cmd) { 4618 case BPF_MAP_CREATE: 4619 err = map_create(&attr); 4620 break; 4621 case BPF_MAP_LOOKUP_ELEM: 4622 err = map_lookup_elem(&attr); 4623 break; 4624 case BPF_MAP_UPDATE_ELEM: 4625 err = map_update_elem(&attr, uattr); 4626 break; 4627 case BPF_MAP_DELETE_ELEM: 4628 err = map_delete_elem(&attr); 4629 break; 4630 case BPF_MAP_GET_NEXT_KEY: 4631 err = map_get_next_key(&attr); 4632 break; 4633 case BPF_MAP_FREEZE: 4634 err = map_freeze(&attr); 4635 break; 4636 case BPF_PROG_LOAD: 4637 err = bpf_prog_load(&attr, uattr); 4638 break; 4639 case BPF_OBJ_PIN: 4640 err = bpf_obj_pin(&attr); 4641 break; 4642 case BPF_OBJ_GET: 4643 err = bpf_obj_get(&attr); 4644 break; 4645 case BPF_PROG_ATTACH: 4646 err = bpf_prog_attach(&attr); 4647 break; 4648 case BPF_PROG_DETACH: 4649 err = bpf_prog_detach(&attr); 4650 break; 4651 case BPF_PROG_QUERY: 4652 err = bpf_prog_query(&attr, uattr.user); 4653 break; 4654 case BPF_PROG_TEST_RUN: 4655 err = bpf_prog_test_run(&attr, uattr.user); 4656 break; 4657 case BPF_PROG_GET_NEXT_ID: 4658 err = bpf_obj_get_next_id(&attr, uattr.user, 4659 &prog_idr, &prog_idr_lock); 4660 break; 4661 case BPF_MAP_GET_NEXT_ID: 4662 err = bpf_obj_get_next_id(&attr, uattr.user, 4663 &map_idr, &map_idr_lock); 4664 break; 4665 case BPF_BTF_GET_NEXT_ID: 4666 err = bpf_obj_get_next_id(&attr, uattr.user, 4667 &btf_idr, &btf_idr_lock); 4668 break; 4669 case BPF_PROG_GET_FD_BY_ID: 4670 err = bpf_prog_get_fd_by_id(&attr); 4671 break; 4672 case BPF_MAP_GET_FD_BY_ID: 4673 err = bpf_map_get_fd_by_id(&attr); 4674 break; 4675 case BPF_OBJ_GET_INFO_BY_FD: 4676 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 4677 break; 4678 case BPF_RAW_TRACEPOINT_OPEN: 4679 err = bpf_raw_tracepoint_open(&attr); 4680 break; 4681 case BPF_BTF_LOAD: 4682 err = bpf_btf_load(&attr, uattr); 4683 break; 4684 case BPF_BTF_GET_FD_BY_ID: 4685 err = bpf_btf_get_fd_by_id(&attr); 4686 break; 4687 case BPF_TASK_FD_QUERY: 4688 err = bpf_task_fd_query(&attr, uattr.user); 4689 break; 4690 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 4691 err = map_lookup_and_delete_elem(&attr); 4692 break; 4693 case BPF_MAP_LOOKUP_BATCH: 4694 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 4695 break; 4696 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 4697 err = bpf_map_do_batch(&attr, uattr.user, 4698 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 4699 break; 4700 case BPF_MAP_UPDATE_BATCH: 4701 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 4702 break; 4703 case BPF_MAP_DELETE_BATCH: 4704 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 4705 break; 4706 case BPF_LINK_CREATE: 4707 err = link_create(&attr, uattr); 4708 break; 4709 case BPF_LINK_UPDATE: 4710 err = link_update(&attr); 4711 break; 4712 case BPF_LINK_GET_FD_BY_ID: 4713 err = bpf_link_get_fd_by_id(&attr); 4714 break; 4715 case BPF_LINK_GET_NEXT_ID: 4716 err = bpf_obj_get_next_id(&attr, uattr.user, 4717 &link_idr, &link_idr_lock); 4718 break; 4719 case BPF_ENABLE_STATS: 4720 err = bpf_enable_stats(&attr); 4721 break; 4722 case BPF_ITER_CREATE: 4723 err = bpf_iter_create(&attr); 4724 break; 4725 case BPF_LINK_DETACH: 4726 err = link_detach(&attr); 4727 break; 4728 case BPF_PROG_BIND_MAP: 4729 err = bpf_prog_bind_map(&attr); 4730 break; 4731 default: 4732 err = -EINVAL; 4733 break; 4734 } 4735 4736 return err; 4737 } 4738 4739 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 4740 { 4741 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 4742 } 4743 4744 static bool syscall_prog_is_valid_access(int off, int size, 4745 enum bpf_access_type type, 4746 const struct bpf_prog *prog, 4747 struct bpf_insn_access_aux *info) 4748 { 4749 if (off < 0 || off >= U16_MAX) 4750 return false; 4751 if (off % size != 0) 4752 return false; 4753 return true; 4754 } 4755 4756 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size) 4757 { 4758 switch (cmd) { 4759 case BPF_MAP_CREATE: 4760 case BPF_MAP_UPDATE_ELEM: 4761 case BPF_MAP_FREEZE: 4762 case BPF_PROG_LOAD: 4763 case BPF_BTF_LOAD: 4764 break; 4765 /* case BPF_PROG_TEST_RUN: 4766 * is not part of this list to prevent recursive test_run 4767 */ 4768 default: 4769 return -EINVAL; 4770 } 4771 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 4772 } 4773 4774 static const struct bpf_func_proto bpf_sys_bpf_proto = { 4775 .func = bpf_sys_bpf, 4776 .gpl_only = false, 4777 .ret_type = RET_INTEGER, 4778 .arg1_type = ARG_ANYTHING, 4779 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 4780 .arg3_type = ARG_CONST_SIZE, 4781 }; 4782 4783 const struct bpf_func_proto * __weak 4784 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4785 { 4786 return bpf_base_func_proto(func_id); 4787 } 4788 4789 BPF_CALL_1(bpf_sys_close, u32, fd) 4790 { 4791 /* When bpf program calls this helper there should not be 4792 * an fdget() without matching completed fdput(). 4793 * This helper is allowed in the following callchain only: 4794 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 4795 */ 4796 return close_fd(fd); 4797 } 4798 4799 static const struct bpf_func_proto bpf_sys_close_proto = { 4800 .func = bpf_sys_close, 4801 .gpl_only = false, 4802 .ret_type = RET_INTEGER, 4803 .arg1_type = ARG_ANYTHING, 4804 }; 4805 4806 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 4807 { 4808 if (flags) 4809 return -EINVAL; 4810 4811 if (name_sz <= 1 || name[name_sz - 1]) 4812 return -EINVAL; 4813 4814 if (!bpf_dump_raw_ok(current_cred())) 4815 return -EPERM; 4816 4817 *res = kallsyms_lookup_name(name); 4818 return *res ? 0 : -ENOENT; 4819 } 4820 4821 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 4822 .func = bpf_kallsyms_lookup_name, 4823 .gpl_only = false, 4824 .ret_type = RET_INTEGER, 4825 .arg1_type = ARG_PTR_TO_MEM, 4826 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 4827 .arg3_type = ARG_ANYTHING, 4828 .arg4_type = ARG_PTR_TO_LONG, 4829 }; 4830 4831 static const struct bpf_func_proto * 4832 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4833 { 4834 switch (func_id) { 4835 case BPF_FUNC_sys_bpf: 4836 return &bpf_sys_bpf_proto; 4837 case BPF_FUNC_btf_find_by_name_kind: 4838 return &bpf_btf_find_by_name_kind_proto; 4839 case BPF_FUNC_sys_close: 4840 return &bpf_sys_close_proto; 4841 case BPF_FUNC_kallsyms_lookup_name: 4842 return &bpf_kallsyms_lookup_name_proto; 4843 default: 4844 return tracing_prog_func_proto(func_id, prog); 4845 } 4846 } 4847 4848 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 4849 .get_func_proto = syscall_prog_func_proto, 4850 .is_valid_access = syscall_prog_is_valid_access, 4851 }; 4852 4853 const struct bpf_prog_ops bpf_syscall_prog_ops = { 4854 .test_run = bpf_prog_test_run_syscall, 4855 }; 4856