1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf_trace.h> 6 #include <linux/bpf_lirc.h> 7 #include <linux/bpf_verifier.h> 8 #include <linux/btf.h> 9 #include <linux/syscalls.h> 10 #include <linux/slab.h> 11 #include <linux/sched/signal.h> 12 #include <linux/vmalloc.h> 13 #include <linux/mmzone.h> 14 #include <linux/anon_inodes.h> 15 #include <linux/fdtable.h> 16 #include <linux/file.h> 17 #include <linux/fs.h> 18 #include <linux/license.h> 19 #include <linux/filter.h> 20 #include <linux/kernel.h> 21 #include <linux/idr.h> 22 #include <linux/cred.h> 23 #include <linux/timekeeping.h> 24 #include <linux/ctype.h> 25 #include <linux/nospec.h> 26 #include <linux/audit.h> 27 #include <uapi/linux/btf.h> 28 #include <linux/pgtable.h> 29 #include <linux/bpf_lsm.h> 30 #include <linux/poll.h> 31 #include <linux/bpf-netns.h> 32 #include <linux/rcupdate_trace.h> 33 #include <linux/memcontrol.h> 34 35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 36 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 37 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 38 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 39 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 41 IS_FD_HASH(map)) 42 43 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 44 45 DEFINE_PER_CPU(int, bpf_prog_active); 46 static DEFINE_IDR(prog_idr); 47 static DEFINE_SPINLOCK(prog_idr_lock); 48 static DEFINE_IDR(map_idr); 49 static DEFINE_SPINLOCK(map_idr_lock); 50 static DEFINE_IDR(link_idr); 51 static DEFINE_SPINLOCK(link_idr_lock); 52 53 int sysctl_unprivileged_bpf_disabled __read_mostly = 54 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 55 56 static const struct bpf_map_ops * const bpf_map_types[] = { 57 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 58 #define BPF_MAP_TYPE(_id, _ops) \ 59 [_id] = &_ops, 60 #define BPF_LINK_TYPE(_id, _name) 61 #include <linux/bpf_types.h> 62 #undef BPF_PROG_TYPE 63 #undef BPF_MAP_TYPE 64 #undef BPF_LINK_TYPE 65 }; 66 67 /* 68 * If we're handed a bigger struct than we know of, ensure all the unknown bits 69 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 70 * we don't know about yet. 71 * 72 * There is a ToCToU between this function call and the following 73 * copy_from_user() call. However, this is not a concern since this function is 74 * meant to be a future-proofing of bits. 75 */ 76 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 77 size_t expected_size, 78 size_t actual_size) 79 { 80 int res; 81 82 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 83 return -E2BIG; 84 85 if (actual_size <= expected_size) 86 return 0; 87 88 if (uaddr.is_kernel) 89 res = memchr_inv(uaddr.kernel + expected_size, 0, 90 actual_size - expected_size) == NULL; 91 else 92 res = check_zeroed_user(uaddr.user + expected_size, 93 actual_size - expected_size); 94 if (res < 0) 95 return res; 96 return res ? 0 : -E2BIG; 97 } 98 99 const struct bpf_map_ops bpf_map_offload_ops = { 100 .map_meta_equal = bpf_map_meta_equal, 101 .map_alloc = bpf_map_offload_map_alloc, 102 .map_free = bpf_map_offload_map_free, 103 .map_check_btf = map_check_no_btf, 104 }; 105 106 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 107 { 108 const struct bpf_map_ops *ops; 109 u32 type = attr->map_type; 110 struct bpf_map *map; 111 int err; 112 113 if (type >= ARRAY_SIZE(bpf_map_types)) 114 return ERR_PTR(-EINVAL); 115 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 116 ops = bpf_map_types[type]; 117 if (!ops) 118 return ERR_PTR(-EINVAL); 119 120 if (ops->map_alloc_check) { 121 err = ops->map_alloc_check(attr); 122 if (err) 123 return ERR_PTR(err); 124 } 125 if (attr->map_ifindex) 126 ops = &bpf_map_offload_ops; 127 map = ops->map_alloc(attr); 128 if (IS_ERR(map)) 129 return map; 130 map->ops = ops; 131 map->map_type = type; 132 return map; 133 } 134 135 static void bpf_map_write_active_inc(struct bpf_map *map) 136 { 137 atomic64_inc(&map->writecnt); 138 } 139 140 static void bpf_map_write_active_dec(struct bpf_map *map) 141 { 142 atomic64_dec(&map->writecnt); 143 } 144 145 bool bpf_map_write_active(const struct bpf_map *map) 146 { 147 return atomic64_read(&map->writecnt) != 0; 148 } 149 150 static u32 bpf_map_value_size(const struct bpf_map *map) 151 { 152 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 153 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 154 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 155 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 156 return round_up(map->value_size, 8) * num_possible_cpus(); 157 else if (IS_FD_MAP(map)) 158 return sizeof(u32); 159 else 160 return map->value_size; 161 } 162 163 static void maybe_wait_bpf_programs(struct bpf_map *map) 164 { 165 /* Wait for any running BPF programs to complete so that 166 * userspace, when we return to it, knows that all programs 167 * that could be running use the new map value. 168 */ 169 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 170 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 171 synchronize_rcu(); 172 } 173 174 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 175 void *value, __u64 flags) 176 { 177 int err; 178 179 /* Need to create a kthread, thus must support schedule */ 180 if (bpf_map_is_dev_bound(map)) { 181 return bpf_map_offload_update_elem(map, key, value, flags); 182 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 183 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 184 return map->ops->map_update_elem(map, key, value, flags); 185 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 186 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 187 return sock_map_update_elem_sys(map, key, value, flags); 188 } else if (IS_FD_PROG_ARRAY(map)) { 189 return bpf_fd_array_map_update_elem(map, f.file, key, value, 190 flags); 191 } 192 193 bpf_disable_instrumentation(); 194 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 195 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 196 err = bpf_percpu_hash_update(map, key, value, flags); 197 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 198 err = bpf_percpu_array_update(map, key, value, flags); 199 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 200 err = bpf_percpu_cgroup_storage_update(map, key, value, 201 flags); 202 } else if (IS_FD_ARRAY(map)) { 203 rcu_read_lock(); 204 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 205 flags); 206 rcu_read_unlock(); 207 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 208 rcu_read_lock(); 209 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 210 flags); 211 rcu_read_unlock(); 212 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 213 /* rcu_read_lock() is not needed */ 214 err = bpf_fd_reuseport_array_update_elem(map, key, value, 215 flags); 216 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 217 map->map_type == BPF_MAP_TYPE_STACK || 218 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 219 err = map->ops->map_push_elem(map, value, flags); 220 } else { 221 rcu_read_lock(); 222 err = map->ops->map_update_elem(map, key, value, flags); 223 rcu_read_unlock(); 224 } 225 bpf_enable_instrumentation(); 226 maybe_wait_bpf_programs(map); 227 228 return err; 229 } 230 231 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 232 __u64 flags) 233 { 234 void *ptr; 235 int err; 236 237 if (bpf_map_is_dev_bound(map)) 238 return bpf_map_offload_lookup_elem(map, key, value); 239 240 bpf_disable_instrumentation(); 241 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 242 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 243 err = bpf_percpu_hash_copy(map, key, value); 244 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 245 err = bpf_percpu_array_copy(map, key, value); 246 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 247 err = bpf_percpu_cgroup_storage_copy(map, key, value); 248 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 249 err = bpf_stackmap_copy(map, key, value); 250 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 251 err = bpf_fd_array_map_lookup_elem(map, key, value); 252 } else if (IS_FD_HASH(map)) { 253 err = bpf_fd_htab_map_lookup_elem(map, key, value); 254 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 255 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 256 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 257 map->map_type == BPF_MAP_TYPE_STACK || 258 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 259 err = map->ops->map_peek_elem(map, value); 260 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 261 /* struct_ops map requires directly updating "value" */ 262 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 263 } else { 264 rcu_read_lock(); 265 if (map->ops->map_lookup_elem_sys_only) 266 ptr = map->ops->map_lookup_elem_sys_only(map, key); 267 else 268 ptr = map->ops->map_lookup_elem(map, key); 269 if (IS_ERR(ptr)) { 270 err = PTR_ERR(ptr); 271 } else if (!ptr) { 272 err = -ENOENT; 273 } else { 274 err = 0; 275 if (flags & BPF_F_LOCK) 276 /* lock 'ptr' and copy everything but lock */ 277 copy_map_value_locked(map, value, ptr, true); 278 else 279 copy_map_value(map, value, ptr); 280 /* mask lock and timer, since value wasn't zero inited */ 281 check_and_init_map_value(map, value); 282 } 283 rcu_read_unlock(); 284 } 285 286 bpf_enable_instrumentation(); 287 maybe_wait_bpf_programs(map); 288 289 return err; 290 } 291 292 /* Please, do not use this function outside from the map creation path 293 * (e.g. in map update path) without taking care of setting the active 294 * memory cgroup (see at bpf_map_kmalloc_node() for example). 295 */ 296 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 297 { 298 /* We really just want to fail instead of triggering OOM killer 299 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 300 * which is used for lower order allocation requests. 301 * 302 * It has been observed that higher order allocation requests done by 303 * vmalloc with __GFP_NORETRY being set might fail due to not trying 304 * to reclaim memory from the page cache, thus we set 305 * __GFP_RETRY_MAYFAIL to avoid such situations. 306 */ 307 308 const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT; 309 unsigned int flags = 0; 310 unsigned long align = 1; 311 void *area; 312 313 if (size >= SIZE_MAX) 314 return NULL; 315 316 /* kmalloc()'ed memory can't be mmap()'ed */ 317 if (mmapable) { 318 BUG_ON(!PAGE_ALIGNED(size)); 319 align = SHMLBA; 320 flags = VM_USERMAP; 321 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 322 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 323 numa_node); 324 if (area != NULL) 325 return area; 326 } 327 328 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 329 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 330 flags, numa_node, __builtin_return_address(0)); 331 } 332 333 void *bpf_map_area_alloc(u64 size, int numa_node) 334 { 335 return __bpf_map_area_alloc(size, numa_node, false); 336 } 337 338 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 339 { 340 return __bpf_map_area_alloc(size, numa_node, true); 341 } 342 343 void bpf_map_area_free(void *area) 344 { 345 kvfree(area); 346 } 347 348 static u32 bpf_map_flags_retain_permanent(u32 flags) 349 { 350 /* Some map creation flags are not tied to the map object but 351 * rather to the map fd instead, so they have no meaning upon 352 * map object inspection since multiple file descriptors with 353 * different (access) properties can exist here. Thus, given 354 * this has zero meaning for the map itself, lets clear these 355 * from here. 356 */ 357 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 358 } 359 360 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 361 { 362 map->map_type = attr->map_type; 363 map->key_size = attr->key_size; 364 map->value_size = attr->value_size; 365 map->max_entries = attr->max_entries; 366 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 367 map->numa_node = bpf_map_attr_numa_node(attr); 368 map->map_extra = attr->map_extra; 369 } 370 371 static int bpf_map_alloc_id(struct bpf_map *map) 372 { 373 int id; 374 375 idr_preload(GFP_KERNEL); 376 spin_lock_bh(&map_idr_lock); 377 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 378 if (id > 0) 379 map->id = id; 380 spin_unlock_bh(&map_idr_lock); 381 idr_preload_end(); 382 383 if (WARN_ON_ONCE(!id)) 384 return -ENOSPC; 385 386 return id > 0 ? 0 : id; 387 } 388 389 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 390 { 391 unsigned long flags; 392 393 /* Offloaded maps are removed from the IDR store when their device 394 * disappears - even if someone holds an fd to them they are unusable, 395 * the memory is gone, all ops will fail; they are simply waiting for 396 * refcnt to drop to be freed. 397 */ 398 if (!map->id) 399 return; 400 401 if (do_idr_lock) 402 spin_lock_irqsave(&map_idr_lock, flags); 403 else 404 __acquire(&map_idr_lock); 405 406 idr_remove(&map_idr, map->id); 407 map->id = 0; 408 409 if (do_idr_lock) 410 spin_unlock_irqrestore(&map_idr_lock, flags); 411 else 412 __release(&map_idr_lock); 413 } 414 415 #ifdef CONFIG_MEMCG_KMEM 416 static void bpf_map_save_memcg(struct bpf_map *map) 417 { 418 map->memcg = get_mem_cgroup_from_mm(current->mm); 419 } 420 421 static void bpf_map_release_memcg(struct bpf_map *map) 422 { 423 mem_cgroup_put(map->memcg); 424 } 425 426 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 427 int node) 428 { 429 struct mem_cgroup *old_memcg; 430 void *ptr; 431 432 old_memcg = set_active_memcg(map->memcg); 433 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 434 set_active_memcg(old_memcg); 435 436 return ptr; 437 } 438 439 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 440 { 441 struct mem_cgroup *old_memcg; 442 void *ptr; 443 444 old_memcg = set_active_memcg(map->memcg); 445 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 446 set_active_memcg(old_memcg); 447 448 return ptr; 449 } 450 451 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 452 size_t align, gfp_t flags) 453 { 454 struct mem_cgroup *old_memcg; 455 void __percpu *ptr; 456 457 old_memcg = set_active_memcg(map->memcg); 458 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 459 set_active_memcg(old_memcg); 460 461 return ptr; 462 } 463 464 #else 465 static void bpf_map_save_memcg(struct bpf_map *map) 466 { 467 } 468 469 static void bpf_map_release_memcg(struct bpf_map *map) 470 { 471 } 472 #endif 473 474 /* called from workqueue */ 475 static void bpf_map_free_deferred(struct work_struct *work) 476 { 477 struct bpf_map *map = container_of(work, struct bpf_map, work); 478 479 security_bpf_map_free(map); 480 bpf_map_release_memcg(map); 481 /* implementation dependent freeing */ 482 map->ops->map_free(map); 483 } 484 485 static void bpf_map_put_uref(struct bpf_map *map) 486 { 487 if (atomic64_dec_and_test(&map->usercnt)) { 488 if (map->ops->map_release_uref) 489 map->ops->map_release_uref(map); 490 } 491 } 492 493 /* decrement map refcnt and schedule it for freeing via workqueue 494 * (unrelying map implementation ops->map_free() might sleep) 495 */ 496 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 497 { 498 if (atomic64_dec_and_test(&map->refcnt)) { 499 /* bpf_map_free_id() must be called first */ 500 bpf_map_free_id(map, do_idr_lock); 501 btf_put(map->btf); 502 INIT_WORK(&map->work, bpf_map_free_deferred); 503 schedule_work(&map->work); 504 } 505 } 506 507 void bpf_map_put(struct bpf_map *map) 508 { 509 __bpf_map_put(map, true); 510 } 511 EXPORT_SYMBOL_GPL(bpf_map_put); 512 513 void bpf_map_put_with_uref(struct bpf_map *map) 514 { 515 bpf_map_put_uref(map); 516 bpf_map_put(map); 517 } 518 519 static int bpf_map_release(struct inode *inode, struct file *filp) 520 { 521 struct bpf_map *map = filp->private_data; 522 523 if (map->ops->map_release) 524 map->ops->map_release(map, filp); 525 526 bpf_map_put_with_uref(map); 527 return 0; 528 } 529 530 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 531 { 532 fmode_t mode = f.file->f_mode; 533 534 /* Our file permissions may have been overridden by global 535 * map permissions facing syscall side. 536 */ 537 if (READ_ONCE(map->frozen)) 538 mode &= ~FMODE_CAN_WRITE; 539 return mode; 540 } 541 542 #ifdef CONFIG_PROC_FS 543 /* Provides an approximation of the map's memory footprint. 544 * Used only to provide a backward compatibility and display 545 * a reasonable "memlock" info. 546 */ 547 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map) 548 { 549 unsigned long size; 550 551 size = round_up(map->key_size + bpf_map_value_size(map), 8); 552 553 return round_up(map->max_entries * size, PAGE_SIZE); 554 } 555 556 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 557 { 558 const struct bpf_map *map = filp->private_data; 559 const struct bpf_array *array; 560 u32 type = 0, jited = 0; 561 562 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 563 array = container_of(map, struct bpf_array, map); 564 spin_lock(&array->aux->owner.lock); 565 type = array->aux->owner.type; 566 jited = array->aux->owner.jited; 567 spin_unlock(&array->aux->owner.lock); 568 } 569 570 seq_printf(m, 571 "map_type:\t%u\n" 572 "key_size:\t%u\n" 573 "value_size:\t%u\n" 574 "max_entries:\t%u\n" 575 "map_flags:\t%#x\n" 576 "map_extra:\t%#llx\n" 577 "memlock:\t%lu\n" 578 "map_id:\t%u\n" 579 "frozen:\t%u\n", 580 map->map_type, 581 map->key_size, 582 map->value_size, 583 map->max_entries, 584 map->map_flags, 585 (unsigned long long)map->map_extra, 586 bpf_map_memory_footprint(map), 587 map->id, 588 READ_ONCE(map->frozen)); 589 if (type) { 590 seq_printf(m, "owner_prog_type:\t%u\n", type); 591 seq_printf(m, "owner_jited:\t%u\n", jited); 592 } 593 } 594 #endif 595 596 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 597 loff_t *ppos) 598 { 599 /* We need this handler such that alloc_file() enables 600 * f_mode with FMODE_CAN_READ. 601 */ 602 return -EINVAL; 603 } 604 605 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 606 size_t siz, loff_t *ppos) 607 { 608 /* We need this handler such that alloc_file() enables 609 * f_mode with FMODE_CAN_WRITE. 610 */ 611 return -EINVAL; 612 } 613 614 /* called for any extra memory-mapped regions (except initial) */ 615 static void bpf_map_mmap_open(struct vm_area_struct *vma) 616 { 617 struct bpf_map *map = vma->vm_file->private_data; 618 619 if (vma->vm_flags & VM_MAYWRITE) 620 bpf_map_write_active_inc(map); 621 } 622 623 /* called for all unmapped memory region (including initial) */ 624 static void bpf_map_mmap_close(struct vm_area_struct *vma) 625 { 626 struct bpf_map *map = vma->vm_file->private_data; 627 628 if (vma->vm_flags & VM_MAYWRITE) 629 bpf_map_write_active_dec(map); 630 } 631 632 static const struct vm_operations_struct bpf_map_default_vmops = { 633 .open = bpf_map_mmap_open, 634 .close = bpf_map_mmap_close, 635 }; 636 637 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 638 { 639 struct bpf_map *map = filp->private_data; 640 int err; 641 642 if (!map->ops->map_mmap || map_value_has_spin_lock(map) || 643 map_value_has_timer(map)) 644 return -ENOTSUPP; 645 646 if (!(vma->vm_flags & VM_SHARED)) 647 return -EINVAL; 648 649 mutex_lock(&map->freeze_mutex); 650 651 if (vma->vm_flags & VM_WRITE) { 652 if (map->frozen) { 653 err = -EPERM; 654 goto out; 655 } 656 /* map is meant to be read-only, so do not allow mapping as 657 * writable, because it's possible to leak a writable page 658 * reference and allows user-space to still modify it after 659 * freezing, while verifier will assume contents do not change 660 */ 661 if (map->map_flags & BPF_F_RDONLY_PROG) { 662 err = -EACCES; 663 goto out; 664 } 665 } 666 667 /* set default open/close callbacks */ 668 vma->vm_ops = &bpf_map_default_vmops; 669 vma->vm_private_data = map; 670 vma->vm_flags &= ~VM_MAYEXEC; 671 if (!(vma->vm_flags & VM_WRITE)) 672 /* disallow re-mapping with PROT_WRITE */ 673 vma->vm_flags &= ~VM_MAYWRITE; 674 675 err = map->ops->map_mmap(map, vma); 676 if (err) 677 goto out; 678 679 if (vma->vm_flags & VM_MAYWRITE) 680 bpf_map_write_active_inc(map); 681 out: 682 mutex_unlock(&map->freeze_mutex); 683 return err; 684 } 685 686 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 687 { 688 struct bpf_map *map = filp->private_data; 689 690 if (map->ops->map_poll) 691 return map->ops->map_poll(map, filp, pts); 692 693 return EPOLLERR; 694 } 695 696 const struct file_operations bpf_map_fops = { 697 #ifdef CONFIG_PROC_FS 698 .show_fdinfo = bpf_map_show_fdinfo, 699 #endif 700 .release = bpf_map_release, 701 .read = bpf_dummy_read, 702 .write = bpf_dummy_write, 703 .mmap = bpf_map_mmap, 704 .poll = bpf_map_poll, 705 }; 706 707 int bpf_map_new_fd(struct bpf_map *map, int flags) 708 { 709 int ret; 710 711 ret = security_bpf_map(map, OPEN_FMODE(flags)); 712 if (ret < 0) 713 return ret; 714 715 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 716 flags | O_CLOEXEC); 717 } 718 719 int bpf_get_file_flag(int flags) 720 { 721 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 722 return -EINVAL; 723 if (flags & BPF_F_RDONLY) 724 return O_RDONLY; 725 if (flags & BPF_F_WRONLY) 726 return O_WRONLY; 727 return O_RDWR; 728 } 729 730 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 731 #define CHECK_ATTR(CMD) \ 732 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 733 sizeof(attr->CMD##_LAST_FIELD), 0, \ 734 sizeof(*attr) - \ 735 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 736 sizeof(attr->CMD##_LAST_FIELD)) != NULL 737 738 /* dst and src must have at least "size" number of bytes. 739 * Return strlen on success and < 0 on error. 740 */ 741 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 742 { 743 const char *end = src + size; 744 const char *orig_src = src; 745 746 memset(dst, 0, size); 747 /* Copy all isalnum(), '_' and '.' chars. */ 748 while (src < end && *src) { 749 if (!isalnum(*src) && 750 *src != '_' && *src != '.') 751 return -EINVAL; 752 *dst++ = *src++; 753 } 754 755 /* No '\0' found in "size" number of bytes */ 756 if (src == end) 757 return -EINVAL; 758 759 return src - orig_src; 760 } 761 762 int map_check_no_btf(const struct bpf_map *map, 763 const struct btf *btf, 764 const struct btf_type *key_type, 765 const struct btf_type *value_type) 766 { 767 return -ENOTSUPP; 768 } 769 770 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 771 u32 btf_key_id, u32 btf_value_id) 772 { 773 const struct btf_type *key_type, *value_type; 774 u32 key_size, value_size; 775 int ret = 0; 776 777 /* Some maps allow key to be unspecified. */ 778 if (btf_key_id) { 779 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 780 if (!key_type || key_size != map->key_size) 781 return -EINVAL; 782 } else { 783 key_type = btf_type_by_id(btf, 0); 784 if (!map->ops->map_check_btf) 785 return -EINVAL; 786 } 787 788 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 789 if (!value_type || value_size != map->value_size) 790 return -EINVAL; 791 792 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 793 794 if (map_value_has_spin_lock(map)) { 795 if (map->map_flags & BPF_F_RDONLY_PROG) 796 return -EACCES; 797 if (map->map_type != BPF_MAP_TYPE_HASH && 798 map->map_type != BPF_MAP_TYPE_ARRAY && 799 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 800 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 801 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 802 map->map_type != BPF_MAP_TYPE_TASK_STORAGE) 803 return -ENOTSUPP; 804 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 805 map->value_size) { 806 WARN_ONCE(1, 807 "verifier bug spin_lock_off %d value_size %d\n", 808 map->spin_lock_off, map->value_size); 809 return -EFAULT; 810 } 811 } 812 813 map->timer_off = btf_find_timer(btf, value_type); 814 if (map_value_has_timer(map)) { 815 if (map->map_flags & BPF_F_RDONLY_PROG) 816 return -EACCES; 817 if (map->map_type != BPF_MAP_TYPE_HASH && 818 map->map_type != BPF_MAP_TYPE_LRU_HASH && 819 map->map_type != BPF_MAP_TYPE_ARRAY) 820 return -EOPNOTSUPP; 821 } 822 823 if (map->ops->map_check_btf) 824 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 825 826 return ret; 827 } 828 829 #define BPF_MAP_CREATE_LAST_FIELD map_extra 830 /* called via syscall */ 831 static int map_create(union bpf_attr *attr) 832 { 833 int numa_node = bpf_map_attr_numa_node(attr); 834 struct bpf_map *map; 835 int f_flags; 836 int err; 837 838 err = CHECK_ATTR(BPF_MAP_CREATE); 839 if (err) 840 return -EINVAL; 841 842 if (attr->btf_vmlinux_value_type_id) { 843 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 844 attr->btf_key_type_id || attr->btf_value_type_id) 845 return -EINVAL; 846 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 847 return -EINVAL; 848 } 849 850 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 851 attr->map_extra != 0) 852 return -EINVAL; 853 854 f_flags = bpf_get_file_flag(attr->map_flags); 855 if (f_flags < 0) 856 return f_flags; 857 858 if (numa_node != NUMA_NO_NODE && 859 ((unsigned int)numa_node >= nr_node_ids || 860 !node_online(numa_node))) 861 return -EINVAL; 862 863 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 864 map = find_and_alloc_map(attr); 865 if (IS_ERR(map)) 866 return PTR_ERR(map); 867 868 err = bpf_obj_name_cpy(map->name, attr->map_name, 869 sizeof(attr->map_name)); 870 if (err < 0) 871 goto free_map; 872 873 atomic64_set(&map->refcnt, 1); 874 atomic64_set(&map->usercnt, 1); 875 mutex_init(&map->freeze_mutex); 876 877 map->spin_lock_off = -EINVAL; 878 map->timer_off = -EINVAL; 879 if (attr->btf_key_type_id || attr->btf_value_type_id || 880 /* Even the map's value is a kernel's struct, 881 * the bpf_prog.o must have BTF to begin with 882 * to figure out the corresponding kernel's 883 * counter part. Thus, attr->btf_fd has 884 * to be valid also. 885 */ 886 attr->btf_vmlinux_value_type_id) { 887 struct btf *btf; 888 889 btf = btf_get_by_fd(attr->btf_fd); 890 if (IS_ERR(btf)) { 891 err = PTR_ERR(btf); 892 goto free_map; 893 } 894 if (btf_is_kernel(btf)) { 895 btf_put(btf); 896 err = -EACCES; 897 goto free_map; 898 } 899 map->btf = btf; 900 901 if (attr->btf_value_type_id) { 902 err = map_check_btf(map, btf, attr->btf_key_type_id, 903 attr->btf_value_type_id); 904 if (err) 905 goto free_map; 906 } 907 908 map->btf_key_type_id = attr->btf_key_type_id; 909 map->btf_value_type_id = attr->btf_value_type_id; 910 map->btf_vmlinux_value_type_id = 911 attr->btf_vmlinux_value_type_id; 912 } 913 914 err = security_bpf_map_alloc(map); 915 if (err) 916 goto free_map; 917 918 err = bpf_map_alloc_id(map); 919 if (err) 920 goto free_map_sec; 921 922 bpf_map_save_memcg(map); 923 924 err = bpf_map_new_fd(map, f_flags); 925 if (err < 0) { 926 /* failed to allocate fd. 927 * bpf_map_put_with_uref() is needed because the above 928 * bpf_map_alloc_id() has published the map 929 * to the userspace and the userspace may 930 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 931 */ 932 bpf_map_put_with_uref(map); 933 return err; 934 } 935 936 return err; 937 938 free_map_sec: 939 security_bpf_map_free(map); 940 free_map: 941 btf_put(map->btf); 942 map->ops->map_free(map); 943 return err; 944 } 945 946 /* if error is returned, fd is released. 947 * On success caller should complete fd access with matching fdput() 948 */ 949 struct bpf_map *__bpf_map_get(struct fd f) 950 { 951 if (!f.file) 952 return ERR_PTR(-EBADF); 953 if (f.file->f_op != &bpf_map_fops) { 954 fdput(f); 955 return ERR_PTR(-EINVAL); 956 } 957 958 return f.file->private_data; 959 } 960 961 void bpf_map_inc(struct bpf_map *map) 962 { 963 atomic64_inc(&map->refcnt); 964 } 965 EXPORT_SYMBOL_GPL(bpf_map_inc); 966 967 void bpf_map_inc_with_uref(struct bpf_map *map) 968 { 969 atomic64_inc(&map->refcnt); 970 atomic64_inc(&map->usercnt); 971 } 972 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 973 974 struct bpf_map *bpf_map_get(u32 ufd) 975 { 976 struct fd f = fdget(ufd); 977 struct bpf_map *map; 978 979 map = __bpf_map_get(f); 980 if (IS_ERR(map)) 981 return map; 982 983 bpf_map_inc(map); 984 fdput(f); 985 986 return map; 987 } 988 989 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 990 { 991 struct fd f = fdget(ufd); 992 struct bpf_map *map; 993 994 map = __bpf_map_get(f); 995 if (IS_ERR(map)) 996 return map; 997 998 bpf_map_inc_with_uref(map); 999 fdput(f); 1000 1001 return map; 1002 } 1003 1004 /* map_idr_lock should have been held */ 1005 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1006 { 1007 int refold; 1008 1009 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1010 if (!refold) 1011 return ERR_PTR(-ENOENT); 1012 if (uref) 1013 atomic64_inc(&map->usercnt); 1014 1015 return map; 1016 } 1017 1018 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1019 { 1020 spin_lock_bh(&map_idr_lock); 1021 map = __bpf_map_inc_not_zero(map, false); 1022 spin_unlock_bh(&map_idr_lock); 1023 1024 return map; 1025 } 1026 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1027 1028 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1029 { 1030 return -ENOTSUPP; 1031 } 1032 1033 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1034 { 1035 if (key_size) 1036 return vmemdup_user(ukey, key_size); 1037 1038 if (ukey) 1039 return ERR_PTR(-EINVAL); 1040 1041 return NULL; 1042 } 1043 1044 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1045 { 1046 if (key_size) 1047 return kvmemdup_bpfptr(ukey, key_size); 1048 1049 if (!bpfptr_is_null(ukey)) 1050 return ERR_PTR(-EINVAL); 1051 1052 return NULL; 1053 } 1054 1055 /* last field in 'union bpf_attr' used by this command */ 1056 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1057 1058 static int map_lookup_elem(union bpf_attr *attr) 1059 { 1060 void __user *ukey = u64_to_user_ptr(attr->key); 1061 void __user *uvalue = u64_to_user_ptr(attr->value); 1062 int ufd = attr->map_fd; 1063 struct bpf_map *map; 1064 void *key, *value; 1065 u32 value_size; 1066 struct fd f; 1067 int err; 1068 1069 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1070 return -EINVAL; 1071 1072 if (attr->flags & ~BPF_F_LOCK) 1073 return -EINVAL; 1074 1075 f = fdget(ufd); 1076 map = __bpf_map_get(f); 1077 if (IS_ERR(map)) 1078 return PTR_ERR(map); 1079 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1080 err = -EPERM; 1081 goto err_put; 1082 } 1083 1084 if ((attr->flags & BPF_F_LOCK) && 1085 !map_value_has_spin_lock(map)) { 1086 err = -EINVAL; 1087 goto err_put; 1088 } 1089 1090 key = __bpf_copy_key(ukey, map->key_size); 1091 if (IS_ERR(key)) { 1092 err = PTR_ERR(key); 1093 goto err_put; 1094 } 1095 1096 value_size = bpf_map_value_size(map); 1097 1098 err = -ENOMEM; 1099 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1100 if (!value) 1101 goto free_key; 1102 1103 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1104 if (copy_from_user(value, uvalue, value_size)) 1105 err = -EFAULT; 1106 else 1107 err = bpf_map_copy_value(map, key, value, attr->flags); 1108 goto free_value; 1109 } 1110 1111 err = bpf_map_copy_value(map, key, value, attr->flags); 1112 if (err) 1113 goto free_value; 1114 1115 err = -EFAULT; 1116 if (copy_to_user(uvalue, value, value_size) != 0) 1117 goto free_value; 1118 1119 err = 0; 1120 1121 free_value: 1122 kvfree(value); 1123 free_key: 1124 kvfree(key); 1125 err_put: 1126 fdput(f); 1127 return err; 1128 } 1129 1130 1131 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1132 1133 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1134 { 1135 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1136 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1137 int ufd = attr->map_fd; 1138 struct bpf_map *map; 1139 void *key, *value; 1140 u32 value_size; 1141 struct fd f; 1142 int err; 1143 1144 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1145 return -EINVAL; 1146 1147 f = fdget(ufd); 1148 map = __bpf_map_get(f); 1149 if (IS_ERR(map)) 1150 return PTR_ERR(map); 1151 bpf_map_write_active_inc(map); 1152 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1153 err = -EPERM; 1154 goto err_put; 1155 } 1156 1157 if ((attr->flags & BPF_F_LOCK) && 1158 !map_value_has_spin_lock(map)) { 1159 err = -EINVAL; 1160 goto err_put; 1161 } 1162 1163 key = ___bpf_copy_key(ukey, map->key_size); 1164 if (IS_ERR(key)) { 1165 err = PTR_ERR(key); 1166 goto err_put; 1167 } 1168 1169 value_size = bpf_map_value_size(map); 1170 1171 err = -ENOMEM; 1172 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1173 if (!value) 1174 goto free_key; 1175 1176 err = -EFAULT; 1177 if (copy_from_bpfptr(value, uvalue, value_size) != 0) 1178 goto free_value; 1179 1180 err = bpf_map_update_value(map, f, key, value, attr->flags); 1181 1182 free_value: 1183 kvfree(value); 1184 free_key: 1185 kvfree(key); 1186 err_put: 1187 bpf_map_write_active_dec(map); 1188 fdput(f); 1189 return err; 1190 } 1191 1192 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1193 1194 static int map_delete_elem(union bpf_attr *attr) 1195 { 1196 void __user *ukey = u64_to_user_ptr(attr->key); 1197 int ufd = attr->map_fd; 1198 struct bpf_map *map; 1199 struct fd f; 1200 void *key; 1201 int err; 1202 1203 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1204 return -EINVAL; 1205 1206 f = fdget(ufd); 1207 map = __bpf_map_get(f); 1208 if (IS_ERR(map)) 1209 return PTR_ERR(map); 1210 bpf_map_write_active_inc(map); 1211 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1212 err = -EPERM; 1213 goto err_put; 1214 } 1215 1216 key = __bpf_copy_key(ukey, map->key_size); 1217 if (IS_ERR(key)) { 1218 err = PTR_ERR(key); 1219 goto err_put; 1220 } 1221 1222 if (bpf_map_is_dev_bound(map)) { 1223 err = bpf_map_offload_delete_elem(map, key); 1224 goto out; 1225 } else if (IS_FD_PROG_ARRAY(map) || 1226 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1227 /* These maps require sleepable context */ 1228 err = map->ops->map_delete_elem(map, key); 1229 goto out; 1230 } 1231 1232 bpf_disable_instrumentation(); 1233 rcu_read_lock(); 1234 err = map->ops->map_delete_elem(map, key); 1235 rcu_read_unlock(); 1236 bpf_enable_instrumentation(); 1237 maybe_wait_bpf_programs(map); 1238 out: 1239 kvfree(key); 1240 err_put: 1241 bpf_map_write_active_dec(map); 1242 fdput(f); 1243 return err; 1244 } 1245 1246 /* last field in 'union bpf_attr' used by this command */ 1247 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1248 1249 static int map_get_next_key(union bpf_attr *attr) 1250 { 1251 void __user *ukey = u64_to_user_ptr(attr->key); 1252 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1253 int ufd = attr->map_fd; 1254 struct bpf_map *map; 1255 void *key, *next_key; 1256 struct fd f; 1257 int err; 1258 1259 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1260 return -EINVAL; 1261 1262 f = fdget(ufd); 1263 map = __bpf_map_get(f); 1264 if (IS_ERR(map)) 1265 return PTR_ERR(map); 1266 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1267 err = -EPERM; 1268 goto err_put; 1269 } 1270 1271 if (ukey) { 1272 key = __bpf_copy_key(ukey, map->key_size); 1273 if (IS_ERR(key)) { 1274 err = PTR_ERR(key); 1275 goto err_put; 1276 } 1277 } else { 1278 key = NULL; 1279 } 1280 1281 err = -ENOMEM; 1282 next_key = kvmalloc(map->key_size, GFP_USER); 1283 if (!next_key) 1284 goto free_key; 1285 1286 if (bpf_map_is_dev_bound(map)) { 1287 err = bpf_map_offload_get_next_key(map, key, next_key); 1288 goto out; 1289 } 1290 1291 rcu_read_lock(); 1292 err = map->ops->map_get_next_key(map, key, next_key); 1293 rcu_read_unlock(); 1294 out: 1295 if (err) 1296 goto free_next_key; 1297 1298 err = -EFAULT; 1299 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1300 goto free_next_key; 1301 1302 err = 0; 1303 1304 free_next_key: 1305 kvfree(next_key); 1306 free_key: 1307 kvfree(key); 1308 err_put: 1309 fdput(f); 1310 return err; 1311 } 1312 1313 int generic_map_delete_batch(struct bpf_map *map, 1314 const union bpf_attr *attr, 1315 union bpf_attr __user *uattr) 1316 { 1317 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1318 u32 cp, max_count; 1319 int err = 0; 1320 void *key; 1321 1322 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1323 return -EINVAL; 1324 1325 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1326 !map_value_has_spin_lock(map)) { 1327 return -EINVAL; 1328 } 1329 1330 max_count = attr->batch.count; 1331 if (!max_count) 1332 return 0; 1333 1334 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1335 if (!key) 1336 return -ENOMEM; 1337 1338 for (cp = 0; cp < max_count; cp++) { 1339 err = -EFAULT; 1340 if (copy_from_user(key, keys + cp * map->key_size, 1341 map->key_size)) 1342 break; 1343 1344 if (bpf_map_is_dev_bound(map)) { 1345 err = bpf_map_offload_delete_elem(map, key); 1346 break; 1347 } 1348 1349 bpf_disable_instrumentation(); 1350 rcu_read_lock(); 1351 err = map->ops->map_delete_elem(map, key); 1352 rcu_read_unlock(); 1353 bpf_enable_instrumentation(); 1354 maybe_wait_bpf_programs(map); 1355 if (err) 1356 break; 1357 } 1358 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1359 err = -EFAULT; 1360 1361 kvfree(key); 1362 return err; 1363 } 1364 1365 int generic_map_update_batch(struct bpf_map *map, 1366 const union bpf_attr *attr, 1367 union bpf_attr __user *uattr) 1368 { 1369 void __user *values = u64_to_user_ptr(attr->batch.values); 1370 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1371 u32 value_size, cp, max_count; 1372 int ufd = attr->batch.map_fd; 1373 void *key, *value; 1374 struct fd f; 1375 int err = 0; 1376 1377 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1378 return -EINVAL; 1379 1380 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1381 !map_value_has_spin_lock(map)) { 1382 return -EINVAL; 1383 } 1384 1385 value_size = bpf_map_value_size(map); 1386 1387 max_count = attr->batch.count; 1388 if (!max_count) 1389 return 0; 1390 1391 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1392 if (!key) 1393 return -ENOMEM; 1394 1395 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1396 if (!value) { 1397 kvfree(key); 1398 return -ENOMEM; 1399 } 1400 1401 f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */ 1402 for (cp = 0; cp < max_count; cp++) { 1403 err = -EFAULT; 1404 if (copy_from_user(key, keys + cp * map->key_size, 1405 map->key_size) || 1406 copy_from_user(value, values + cp * value_size, value_size)) 1407 break; 1408 1409 err = bpf_map_update_value(map, f, key, value, 1410 attr->batch.elem_flags); 1411 1412 if (err) 1413 break; 1414 } 1415 1416 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1417 err = -EFAULT; 1418 1419 kvfree(value); 1420 kvfree(key); 1421 fdput(f); 1422 return err; 1423 } 1424 1425 #define MAP_LOOKUP_RETRIES 3 1426 1427 int generic_map_lookup_batch(struct bpf_map *map, 1428 const union bpf_attr *attr, 1429 union bpf_attr __user *uattr) 1430 { 1431 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1432 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1433 void __user *values = u64_to_user_ptr(attr->batch.values); 1434 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1435 void *buf, *buf_prevkey, *prev_key, *key, *value; 1436 int err, retry = MAP_LOOKUP_RETRIES; 1437 u32 value_size, cp, max_count; 1438 1439 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1440 return -EINVAL; 1441 1442 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1443 !map_value_has_spin_lock(map)) 1444 return -EINVAL; 1445 1446 value_size = bpf_map_value_size(map); 1447 1448 max_count = attr->batch.count; 1449 if (!max_count) 1450 return 0; 1451 1452 if (put_user(0, &uattr->batch.count)) 1453 return -EFAULT; 1454 1455 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1456 if (!buf_prevkey) 1457 return -ENOMEM; 1458 1459 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1460 if (!buf) { 1461 kvfree(buf_prevkey); 1462 return -ENOMEM; 1463 } 1464 1465 err = -EFAULT; 1466 prev_key = NULL; 1467 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1468 goto free_buf; 1469 key = buf; 1470 value = key + map->key_size; 1471 if (ubatch) 1472 prev_key = buf_prevkey; 1473 1474 for (cp = 0; cp < max_count;) { 1475 rcu_read_lock(); 1476 err = map->ops->map_get_next_key(map, prev_key, key); 1477 rcu_read_unlock(); 1478 if (err) 1479 break; 1480 err = bpf_map_copy_value(map, key, value, 1481 attr->batch.elem_flags); 1482 1483 if (err == -ENOENT) { 1484 if (retry) { 1485 retry--; 1486 continue; 1487 } 1488 err = -EINTR; 1489 break; 1490 } 1491 1492 if (err) 1493 goto free_buf; 1494 1495 if (copy_to_user(keys + cp * map->key_size, key, 1496 map->key_size)) { 1497 err = -EFAULT; 1498 goto free_buf; 1499 } 1500 if (copy_to_user(values + cp * value_size, value, value_size)) { 1501 err = -EFAULT; 1502 goto free_buf; 1503 } 1504 1505 if (!prev_key) 1506 prev_key = buf_prevkey; 1507 1508 swap(prev_key, key); 1509 retry = MAP_LOOKUP_RETRIES; 1510 cp++; 1511 } 1512 1513 if (err == -EFAULT) 1514 goto free_buf; 1515 1516 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1517 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1518 err = -EFAULT; 1519 1520 free_buf: 1521 kvfree(buf_prevkey); 1522 kvfree(buf); 1523 return err; 1524 } 1525 1526 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 1527 1528 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1529 { 1530 void __user *ukey = u64_to_user_ptr(attr->key); 1531 void __user *uvalue = u64_to_user_ptr(attr->value); 1532 int ufd = attr->map_fd; 1533 struct bpf_map *map; 1534 void *key, *value; 1535 u32 value_size; 1536 struct fd f; 1537 int err; 1538 1539 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1540 return -EINVAL; 1541 1542 if (attr->flags & ~BPF_F_LOCK) 1543 return -EINVAL; 1544 1545 f = fdget(ufd); 1546 map = __bpf_map_get(f); 1547 if (IS_ERR(map)) 1548 return PTR_ERR(map); 1549 bpf_map_write_active_inc(map); 1550 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 1551 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1552 err = -EPERM; 1553 goto err_put; 1554 } 1555 1556 if (attr->flags && 1557 (map->map_type == BPF_MAP_TYPE_QUEUE || 1558 map->map_type == BPF_MAP_TYPE_STACK)) { 1559 err = -EINVAL; 1560 goto err_put; 1561 } 1562 1563 if ((attr->flags & BPF_F_LOCK) && 1564 !map_value_has_spin_lock(map)) { 1565 err = -EINVAL; 1566 goto err_put; 1567 } 1568 1569 key = __bpf_copy_key(ukey, map->key_size); 1570 if (IS_ERR(key)) { 1571 err = PTR_ERR(key); 1572 goto err_put; 1573 } 1574 1575 value_size = bpf_map_value_size(map); 1576 1577 err = -ENOMEM; 1578 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1579 if (!value) 1580 goto free_key; 1581 1582 err = -ENOTSUPP; 1583 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1584 map->map_type == BPF_MAP_TYPE_STACK) { 1585 err = map->ops->map_pop_elem(map, value); 1586 } else if (map->map_type == BPF_MAP_TYPE_HASH || 1587 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1588 map->map_type == BPF_MAP_TYPE_LRU_HASH || 1589 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 1590 if (!bpf_map_is_dev_bound(map)) { 1591 bpf_disable_instrumentation(); 1592 rcu_read_lock(); 1593 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 1594 rcu_read_unlock(); 1595 bpf_enable_instrumentation(); 1596 } 1597 } 1598 1599 if (err) 1600 goto free_value; 1601 1602 if (copy_to_user(uvalue, value, value_size) != 0) { 1603 err = -EFAULT; 1604 goto free_value; 1605 } 1606 1607 err = 0; 1608 1609 free_value: 1610 kvfree(value); 1611 free_key: 1612 kvfree(key); 1613 err_put: 1614 bpf_map_write_active_dec(map); 1615 fdput(f); 1616 return err; 1617 } 1618 1619 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1620 1621 static int map_freeze(const union bpf_attr *attr) 1622 { 1623 int err = 0, ufd = attr->map_fd; 1624 struct bpf_map *map; 1625 struct fd f; 1626 1627 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1628 return -EINVAL; 1629 1630 f = fdget(ufd); 1631 map = __bpf_map_get(f); 1632 if (IS_ERR(map)) 1633 return PTR_ERR(map); 1634 1635 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || 1636 map_value_has_timer(map)) { 1637 fdput(f); 1638 return -ENOTSUPP; 1639 } 1640 1641 mutex_lock(&map->freeze_mutex); 1642 if (bpf_map_write_active(map)) { 1643 err = -EBUSY; 1644 goto err_put; 1645 } 1646 if (READ_ONCE(map->frozen)) { 1647 err = -EBUSY; 1648 goto err_put; 1649 } 1650 if (!bpf_capable()) { 1651 err = -EPERM; 1652 goto err_put; 1653 } 1654 1655 WRITE_ONCE(map->frozen, true); 1656 err_put: 1657 mutex_unlock(&map->freeze_mutex); 1658 fdput(f); 1659 return err; 1660 } 1661 1662 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1663 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1664 [_id] = & _name ## _prog_ops, 1665 #define BPF_MAP_TYPE(_id, _ops) 1666 #define BPF_LINK_TYPE(_id, _name) 1667 #include <linux/bpf_types.h> 1668 #undef BPF_PROG_TYPE 1669 #undef BPF_MAP_TYPE 1670 #undef BPF_LINK_TYPE 1671 }; 1672 1673 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1674 { 1675 const struct bpf_prog_ops *ops; 1676 1677 if (type >= ARRAY_SIZE(bpf_prog_types)) 1678 return -EINVAL; 1679 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1680 ops = bpf_prog_types[type]; 1681 if (!ops) 1682 return -EINVAL; 1683 1684 if (!bpf_prog_is_dev_bound(prog->aux)) 1685 prog->aux->ops = ops; 1686 else 1687 prog->aux->ops = &bpf_offload_prog_ops; 1688 prog->type = type; 1689 return 0; 1690 } 1691 1692 enum bpf_audit { 1693 BPF_AUDIT_LOAD, 1694 BPF_AUDIT_UNLOAD, 1695 BPF_AUDIT_MAX, 1696 }; 1697 1698 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1699 [BPF_AUDIT_LOAD] = "LOAD", 1700 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1701 }; 1702 1703 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1704 { 1705 struct audit_context *ctx = NULL; 1706 struct audit_buffer *ab; 1707 1708 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1709 return; 1710 if (audit_enabled == AUDIT_OFF) 1711 return; 1712 if (op == BPF_AUDIT_LOAD) 1713 ctx = audit_context(); 1714 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1715 if (unlikely(!ab)) 1716 return; 1717 audit_log_format(ab, "prog-id=%u op=%s", 1718 prog->aux->id, bpf_audit_str[op]); 1719 audit_log_end(ab); 1720 } 1721 1722 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1723 { 1724 int id; 1725 1726 idr_preload(GFP_KERNEL); 1727 spin_lock_bh(&prog_idr_lock); 1728 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1729 if (id > 0) 1730 prog->aux->id = id; 1731 spin_unlock_bh(&prog_idr_lock); 1732 idr_preload_end(); 1733 1734 /* id is in [1, INT_MAX) */ 1735 if (WARN_ON_ONCE(!id)) 1736 return -ENOSPC; 1737 1738 return id > 0 ? 0 : id; 1739 } 1740 1741 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1742 { 1743 unsigned long flags; 1744 1745 /* cBPF to eBPF migrations are currently not in the idr store. 1746 * Offloaded programs are removed from the store when their device 1747 * disappears - even if someone grabs an fd to them they are unusable, 1748 * simply waiting for refcnt to drop to be freed. 1749 */ 1750 if (!prog->aux->id) 1751 return; 1752 1753 if (do_idr_lock) 1754 spin_lock_irqsave(&prog_idr_lock, flags); 1755 else 1756 __acquire(&prog_idr_lock); 1757 1758 idr_remove(&prog_idr, prog->aux->id); 1759 prog->aux->id = 0; 1760 1761 if (do_idr_lock) 1762 spin_unlock_irqrestore(&prog_idr_lock, flags); 1763 else 1764 __release(&prog_idr_lock); 1765 } 1766 1767 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1768 { 1769 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1770 1771 kvfree(aux->func_info); 1772 kfree(aux->func_info_aux); 1773 free_uid(aux->user); 1774 security_bpf_prog_free(aux); 1775 bpf_prog_free(aux->prog); 1776 } 1777 1778 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1779 { 1780 bpf_prog_kallsyms_del_all(prog); 1781 btf_put(prog->aux->btf); 1782 kvfree(prog->aux->jited_linfo); 1783 kvfree(prog->aux->linfo); 1784 kfree(prog->aux->kfunc_tab); 1785 if (prog->aux->attach_btf) 1786 btf_put(prog->aux->attach_btf); 1787 1788 if (deferred) { 1789 if (prog->aux->sleepable) 1790 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 1791 else 1792 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1793 } else { 1794 __bpf_prog_put_rcu(&prog->aux->rcu); 1795 } 1796 } 1797 1798 static void bpf_prog_put_deferred(struct work_struct *work) 1799 { 1800 struct bpf_prog_aux *aux; 1801 struct bpf_prog *prog; 1802 1803 aux = container_of(work, struct bpf_prog_aux, work); 1804 prog = aux->prog; 1805 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1806 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1807 __bpf_prog_put_noref(prog, true); 1808 } 1809 1810 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1811 { 1812 struct bpf_prog_aux *aux = prog->aux; 1813 1814 if (atomic64_dec_and_test(&aux->refcnt)) { 1815 /* bpf_prog_free_id() must be called first */ 1816 bpf_prog_free_id(prog, do_idr_lock); 1817 1818 if (in_irq() || irqs_disabled()) { 1819 INIT_WORK(&aux->work, bpf_prog_put_deferred); 1820 schedule_work(&aux->work); 1821 } else { 1822 bpf_prog_put_deferred(&aux->work); 1823 } 1824 } 1825 } 1826 1827 void bpf_prog_put(struct bpf_prog *prog) 1828 { 1829 __bpf_prog_put(prog, true); 1830 } 1831 EXPORT_SYMBOL_GPL(bpf_prog_put); 1832 1833 static int bpf_prog_release(struct inode *inode, struct file *filp) 1834 { 1835 struct bpf_prog *prog = filp->private_data; 1836 1837 bpf_prog_put(prog); 1838 return 0; 1839 } 1840 1841 struct bpf_prog_kstats { 1842 u64 nsecs; 1843 u64 cnt; 1844 u64 misses; 1845 }; 1846 1847 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1848 struct bpf_prog_kstats *stats) 1849 { 1850 u64 nsecs = 0, cnt = 0, misses = 0; 1851 int cpu; 1852 1853 for_each_possible_cpu(cpu) { 1854 const struct bpf_prog_stats *st; 1855 unsigned int start; 1856 u64 tnsecs, tcnt, tmisses; 1857 1858 st = per_cpu_ptr(prog->stats, cpu); 1859 do { 1860 start = u64_stats_fetch_begin_irq(&st->syncp); 1861 tnsecs = u64_stats_read(&st->nsecs); 1862 tcnt = u64_stats_read(&st->cnt); 1863 tmisses = u64_stats_read(&st->misses); 1864 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1865 nsecs += tnsecs; 1866 cnt += tcnt; 1867 misses += tmisses; 1868 } 1869 stats->nsecs = nsecs; 1870 stats->cnt = cnt; 1871 stats->misses = misses; 1872 } 1873 1874 #ifdef CONFIG_PROC_FS 1875 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1876 { 1877 const struct bpf_prog *prog = filp->private_data; 1878 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1879 struct bpf_prog_kstats stats; 1880 1881 bpf_prog_get_stats(prog, &stats); 1882 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1883 seq_printf(m, 1884 "prog_type:\t%u\n" 1885 "prog_jited:\t%u\n" 1886 "prog_tag:\t%s\n" 1887 "memlock:\t%llu\n" 1888 "prog_id:\t%u\n" 1889 "run_time_ns:\t%llu\n" 1890 "run_cnt:\t%llu\n" 1891 "recursion_misses:\t%llu\n" 1892 "verified_insns:\t%u\n", 1893 prog->type, 1894 prog->jited, 1895 prog_tag, 1896 prog->pages * 1ULL << PAGE_SHIFT, 1897 prog->aux->id, 1898 stats.nsecs, 1899 stats.cnt, 1900 stats.misses, 1901 prog->aux->verified_insns); 1902 } 1903 #endif 1904 1905 const struct file_operations bpf_prog_fops = { 1906 #ifdef CONFIG_PROC_FS 1907 .show_fdinfo = bpf_prog_show_fdinfo, 1908 #endif 1909 .release = bpf_prog_release, 1910 .read = bpf_dummy_read, 1911 .write = bpf_dummy_write, 1912 }; 1913 1914 int bpf_prog_new_fd(struct bpf_prog *prog) 1915 { 1916 int ret; 1917 1918 ret = security_bpf_prog(prog); 1919 if (ret < 0) 1920 return ret; 1921 1922 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1923 O_RDWR | O_CLOEXEC); 1924 } 1925 1926 static struct bpf_prog *____bpf_prog_get(struct fd f) 1927 { 1928 if (!f.file) 1929 return ERR_PTR(-EBADF); 1930 if (f.file->f_op != &bpf_prog_fops) { 1931 fdput(f); 1932 return ERR_PTR(-EINVAL); 1933 } 1934 1935 return f.file->private_data; 1936 } 1937 1938 void bpf_prog_add(struct bpf_prog *prog, int i) 1939 { 1940 atomic64_add(i, &prog->aux->refcnt); 1941 } 1942 EXPORT_SYMBOL_GPL(bpf_prog_add); 1943 1944 void bpf_prog_sub(struct bpf_prog *prog, int i) 1945 { 1946 /* Only to be used for undoing previous bpf_prog_add() in some 1947 * error path. We still know that another entity in our call 1948 * path holds a reference to the program, thus atomic_sub() can 1949 * be safely used in such cases! 1950 */ 1951 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1952 } 1953 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1954 1955 void bpf_prog_inc(struct bpf_prog *prog) 1956 { 1957 atomic64_inc(&prog->aux->refcnt); 1958 } 1959 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1960 1961 /* prog_idr_lock should have been held */ 1962 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1963 { 1964 int refold; 1965 1966 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1967 1968 if (!refold) 1969 return ERR_PTR(-ENOENT); 1970 1971 return prog; 1972 } 1973 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1974 1975 bool bpf_prog_get_ok(struct bpf_prog *prog, 1976 enum bpf_prog_type *attach_type, bool attach_drv) 1977 { 1978 /* not an attachment, just a refcount inc, always allow */ 1979 if (!attach_type) 1980 return true; 1981 1982 if (prog->type != *attach_type) 1983 return false; 1984 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1985 return false; 1986 1987 return true; 1988 } 1989 1990 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1991 bool attach_drv) 1992 { 1993 struct fd f = fdget(ufd); 1994 struct bpf_prog *prog; 1995 1996 prog = ____bpf_prog_get(f); 1997 if (IS_ERR(prog)) 1998 return prog; 1999 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 2000 prog = ERR_PTR(-EINVAL); 2001 goto out; 2002 } 2003 2004 bpf_prog_inc(prog); 2005 out: 2006 fdput(f); 2007 return prog; 2008 } 2009 2010 struct bpf_prog *bpf_prog_get(u32 ufd) 2011 { 2012 return __bpf_prog_get(ufd, NULL, false); 2013 } 2014 2015 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2016 bool attach_drv) 2017 { 2018 return __bpf_prog_get(ufd, &type, attach_drv); 2019 } 2020 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2021 2022 /* Initially all BPF programs could be loaded w/o specifying 2023 * expected_attach_type. Later for some of them specifying expected_attach_type 2024 * at load time became required so that program could be validated properly. 2025 * Programs of types that are allowed to be loaded both w/ and w/o (for 2026 * backward compatibility) expected_attach_type, should have the default attach 2027 * type assigned to expected_attach_type for the latter case, so that it can be 2028 * validated later at attach time. 2029 * 2030 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2031 * prog type requires it but has some attach types that have to be backward 2032 * compatible. 2033 */ 2034 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2035 { 2036 switch (attr->prog_type) { 2037 case BPF_PROG_TYPE_CGROUP_SOCK: 2038 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2039 * exist so checking for non-zero is the way to go here. 2040 */ 2041 if (!attr->expected_attach_type) 2042 attr->expected_attach_type = 2043 BPF_CGROUP_INET_SOCK_CREATE; 2044 break; 2045 case BPF_PROG_TYPE_SK_REUSEPORT: 2046 if (!attr->expected_attach_type) 2047 attr->expected_attach_type = 2048 BPF_SK_REUSEPORT_SELECT; 2049 break; 2050 } 2051 } 2052 2053 static int 2054 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2055 enum bpf_attach_type expected_attach_type, 2056 struct btf *attach_btf, u32 btf_id, 2057 struct bpf_prog *dst_prog) 2058 { 2059 if (btf_id) { 2060 if (btf_id > BTF_MAX_TYPE) 2061 return -EINVAL; 2062 2063 if (!attach_btf && !dst_prog) 2064 return -EINVAL; 2065 2066 switch (prog_type) { 2067 case BPF_PROG_TYPE_TRACING: 2068 case BPF_PROG_TYPE_LSM: 2069 case BPF_PROG_TYPE_STRUCT_OPS: 2070 case BPF_PROG_TYPE_EXT: 2071 break; 2072 default: 2073 return -EINVAL; 2074 } 2075 } 2076 2077 if (attach_btf && (!btf_id || dst_prog)) 2078 return -EINVAL; 2079 2080 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2081 prog_type != BPF_PROG_TYPE_EXT) 2082 return -EINVAL; 2083 2084 switch (prog_type) { 2085 case BPF_PROG_TYPE_CGROUP_SOCK: 2086 switch (expected_attach_type) { 2087 case BPF_CGROUP_INET_SOCK_CREATE: 2088 case BPF_CGROUP_INET_SOCK_RELEASE: 2089 case BPF_CGROUP_INET4_POST_BIND: 2090 case BPF_CGROUP_INET6_POST_BIND: 2091 return 0; 2092 default: 2093 return -EINVAL; 2094 } 2095 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2096 switch (expected_attach_type) { 2097 case BPF_CGROUP_INET4_BIND: 2098 case BPF_CGROUP_INET6_BIND: 2099 case BPF_CGROUP_INET4_CONNECT: 2100 case BPF_CGROUP_INET6_CONNECT: 2101 case BPF_CGROUP_INET4_GETPEERNAME: 2102 case BPF_CGROUP_INET6_GETPEERNAME: 2103 case BPF_CGROUP_INET4_GETSOCKNAME: 2104 case BPF_CGROUP_INET6_GETSOCKNAME: 2105 case BPF_CGROUP_UDP4_SENDMSG: 2106 case BPF_CGROUP_UDP6_SENDMSG: 2107 case BPF_CGROUP_UDP4_RECVMSG: 2108 case BPF_CGROUP_UDP6_RECVMSG: 2109 return 0; 2110 default: 2111 return -EINVAL; 2112 } 2113 case BPF_PROG_TYPE_CGROUP_SKB: 2114 switch (expected_attach_type) { 2115 case BPF_CGROUP_INET_INGRESS: 2116 case BPF_CGROUP_INET_EGRESS: 2117 return 0; 2118 default: 2119 return -EINVAL; 2120 } 2121 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2122 switch (expected_attach_type) { 2123 case BPF_CGROUP_SETSOCKOPT: 2124 case BPF_CGROUP_GETSOCKOPT: 2125 return 0; 2126 default: 2127 return -EINVAL; 2128 } 2129 case BPF_PROG_TYPE_SK_LOOKUP: 2130 if (expected_attach_type == BPF_SK_LOOKUP) 2131 return 0; 2132 return -EINVAL; 2133 case BPF_PROG_TYPE_SK_REUSEPORT: 2134 switch (expected_attach_type) { 2135 case BPF_SK_REUSEPORT_SELECT: 2136 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2137 return 0; 2138 default: 2139 return -EINVAL; 2140 } 2141 case BPF_PROG_TYPE_SYSCALL: 2142 case BPF_PROG_TYPE_EXT: 2143 if (expected_attach_type) 2144 return -EINVAL; 2145 fallthrough; 2146 default: 2147 return 0; 2148 } 2149 } 2150 2151 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2152 { 2153 switch (prog_type) { 2154 case BPF_PROG_TYPE_SCHED_CLS: 2155 case BPF_PROG_TYPE_SCHED_ACT: 2156 case BPF_PROG_TYPE_XDP: 2157 case BPF_PROG_TYPE_LWT_IN: 2158 case BPF_PROG_TYPE_LWT_OUT: 2159 case BPF_PROG_TYPE_LWT_XMIT: 2160 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2161 case BPF_PROG_TYPE_SK_SKB: 2162 case BPF_PROG_TYPE_SK_MSG: 2163 case BPF_PROG_TYPE_LIRC_MODE2: 2164 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2165 case BPF_PROG_TYPE_CGROUP_DEVICE: 2166 case BPF_PROG_TYPE_CGROUP_SOCK: 2167 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2168 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2169 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2170 case BPF_PROG_TYPE_SOCK_OPS: 2171 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2172 return true; 2173 case BPF_PROG_TYPE_CGROUP_SKB: 2174 /* always unpriv */ 2175 case BPF_PROG_TYPE_SK_REUSEPORT: 2176 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2177 default: 2178 return false; 2179 } 2180 } 2181 2182 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2183 { 2184 switch (prog_type) { 2185 case BPF_PROG_TYPE_KPROBE: 2186 case BPF_PROG_TYPE_TRACEPOINT: 2187 case BPF_PROG_TYPE_PERF_EVENT: 2188 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2189 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2190 case BPF_PROG_TYPE_TRACING: 2191 case BPF_PROG_TYPE_LSM: 2192 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2193 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2194 return true; 2195 default: 2196 return false; 2197 } 2198 } 2199 2200 /* last field in 'union bpf_attr' used by this command */ 2201 #define BPF_PROG_LOAD_LAST_FIELD fd_array 2202 2203 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr) 2204 { 2205 enum bpf_prog_type type = attr->prog_type; 2206 struct bpf_prog *prog, *dst_prog = NULL; 2207 struct btf *attach_btf = NULL; 2208 int err; 2209 char license[128]; 2210 bool is_gpl; 2211 2212 if (CHECK_ATTR(BPF_PROG_LOAD)) 2213 return -EINVAL; 2214 2215 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2216 BPF_F_ANY_ALIGNMENT | 2217 BPF_F_TEST_STATE_FREQ | 2218 BPF_F_SLEEPABLE | 2219 BPF_F_TEST_RND_HI32)) 2220 return -EINVAL; 2221 2222 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2223 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2224 !bpf_capable()) 2225 return -EPERM; 2226 2227 /* copy eBPF program license from user space */ 2228 if (strncpy_from_bpfptr(license, 2229 make_bpfptr(attr->license, uattr.is_kernel), 2230 sizeof(license) - 1) < 0) 2231 return -EFAULT; 2232 license[sizeof(license) - 1] = 0; 2233 2234 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2235 is_gpl = license_is_gpl_compatible(license); 2236 2237 if (attr->insn_cnt == 0 || 2238 attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2239 return -E2BIG; 2240 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2241 type != BPF_PROG_TYPE_CGROUP_SKB && 2242 !bpf_capable()) 2243 return -EPERM; 2244 2245 if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN)) 2246 return -EPERM; 2247 if (is_perfmon_prog_type(type) && !perfmon_capable()) 2248 return -EPERM; 2249 2250 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2251 * or btf, we need to check which one it is 2252 */ 2253 if (attr->attach_prog_fd) { 2254 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2255 if (IS_ERR(dst_prog)) { 2256 dst_prog = NULL; 2257 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2258 if (IS_ERR(attach_btf)) 2259 return -EINVAL; 2260 if (!btf_is_kernel(attach_btf)) { 2261 /* attaching through specifying bpf_prog's BTF 2262 * objects directly might be supported eventually 2263 */ 2264 btf_put(attach_btf); 2265 return -ENOTSUPP; 2266 } 2267 } 2268 } else if (attr->attach_btf_id) { 2269 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2270 attach_btf = bpf_get_btf_vmlinux(); 2271 if (IS_ERR(attach_btf)) 2272 return PTR_ERR(attach_btf); 2273 if (!attach_btf) 2274 return -EINVAL; 2275 btf_get(attach_btf); 2276 } 2277 2278 bpf_prog_load_fixup_attach_type(attr); 2279 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2280 attach_btf, attr->attach_btf_id, 2281 dst_prog)) { 2282 if (dst_prog) 2283 bpf_prog_put(dst_prog); 2284 if (attach_btf) 2285 btf_put(attach_btf); 2286 return -EINVAL; 2287 } 2288 2289 /* plain bpf_prog allocation */ 2290 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2291 if (!prog) { 2292 if (dst_prog) 2293 bpf_prog_put(dst_prog); 2294 if (attach_btf) 2295 btf_put(attach_btf); 2296 return -ENOMEM; 2297 } 2298 2299 prog->expected_attach_type = attr->expected_attach_type; 2300 prog->aux->attach_btf = attach_btf; 2301 prog->aux->attach_btf_id = attr->attach_btf_id; 2302 prog->aux->dst_prog = dst_prog; 2303 prog->aux->offload_requested = !!attr->prog_ifindex; 2304 prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; 2305 2306 err = security_bpf_prog_alloc(prog->aux); 2307 if (err) 2308 goto free_prog; 2309 2310 prog->aux->user = get_current_user(); 2311 prog->len = attr->insn_cnt; 2312 2313 err = -EFAULT; 2314 if (copy_from_bpfptr(prog->insns, 2315 make_bpfptr(attr->insns, uattr.is_kernel), 2316 bpf_prog_insn_size(prog)) != 0) 2317 goto free_prog_sec; 2318 2319 prog->orig_prog = NULL; 2320 prog->jited = 0; 2321 2322 atomic64_set(&prog->aux->refcnt, 1); 2323 prog->gpl_compatible = is_gpl ? 1 : 0; 2324 2325 if (bpf_prog_is_dev_bound(prog->aux)) { 2326 err = bpf_prog_offload_init(prog, attr); 2327 if (err) 2328 goto free_prog_sec; 2329 } 2330 2331 /* find program type: socket_filter vs tracing_filter */ 2332 err = find_prog_type(type, prog); 2333 if (err < 0) 2334 goto free_prog_sec; 2335 2336 prog->aux->load_time = ktime_get_boottime_ns(); 2337 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2338 sizeof(attr->prog_name)); 2339 if (err < 0) 2340 goto free_prog_sec; 2341 2342 /* run eBPF verifier */ 2343 err = bpf_check(&prog, attr, uattr); 2344 if (err < 0) 2345 goto free_used_maps; 2346 2347 prog = bpf_prog_select_runtime(prog, &err); 2348 if (err < 0) 2349 goto free_used_maps; 2350 2351 err = bpf_prog_alloc_id(prog); 2352 if (err) 2353 goto free_used_maps; 2354 2355 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2356 * effectively publicly exposed. However, retrieving via 2357 * bpf_prog_get_fd_by_id() will take another reference, 2358 * therefore it cannot be gone underneath us. 2359 * 2360 * Only for the time /after/ successful bpf_prog_new_fd() 2361 * and before returning to userspace, we might just hold 2362 * one reference and any parallel close on that fd could 2363 * rip everything out. Hence, below notifications must 2364 * happen before bpf_prog_new_fd(). 2365 * 2366 * Also, any failure handling from this point onwards must 2367 * be using bpf_prog_put() given the program is exposed. 2368 */ 2369 bpf_prog_kallsyms_add(prog); 2370 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2371 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2372 2373 err = bpf_prog_new_fd(prog); 2374 if (err < 0) 2375 bpf_prog_put(prog); 2376 return err; 2377 2378 free_used_maps: 2379 /* In case we have subprogs, we need to wait for a grace 2380 * period before we can tear down JIT memory since symbols 2381 * are already exposed under kallsyms. 2382 */ 2383 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2384 return err; 2385 free_prog_sec: 2386 free_uid(prog->aux->user); 2387 security_bpf_prog_free(prog->aux); 2388 free_prog: 2389 if (prog->aux->attach_btf) 2390 btf_put(prog->aux->attach_btf); 2391 bpf_prog_free(prog); 2392 return err; 2393 } 2394 2395 #define BPF_OBJ_LAST_FIELD file_flags 2396 2397 static int bpf_obj_pin(const union bpf_attr *attr) 2398 { 2399 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2400 return -EINVAL; 2401 2402 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2403 } 2404 2405 static int bpf_obj_get(const union bpf_attr *attr) 2406 { 2407 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2408 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2409 return -EINVAL; 2410 2411 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2412 attr->file_flags); 2413 } 2414 2415 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2416 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2417 { 2418 atomic64_set(&link->refcnt, 1); 2419 link->type = type; 2420 link->id = 0; 2421 link->ops = ops; 2422 link->prog = prog; 2423 } 2424 2425 static void bpf_link_free_id(int id) 2426 { 2427 if (!id) 2428 return; 2429 2430 spin_lock_bh(&link_idr_lock); 2431 idr_remove(&link_idr, id); 2432 spin_unlock_bh(&link_idr_lock); 2433 } 2434 2435 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2436 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2437 * anon_inode's release() call. This helper marksbpf_link as 2438 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 2439 * is not decremented, it's the responsibility of a calling code that failed 2440 * to complete bpf_link initialization. 2441 */ 2442 void bpf_link_cleanup(struct bpf_link_primer *primer) 2443 { 2444 primer->link->prog = NULL; 2445 bpf_link_free_id(primer->id); 2446 fput(primer->file); 2447 put_unused_fd(primer->fd); 2448 } 2449 2450 void bpf_link_inc(struct bpf_link *link) 2451 { 2452 atomic64_inc(&link->refcnt); 2453 } 2454 2455 /* bpf_link_free is guaranteed to be called from process context */ 2456 static void bpf_link_free(struct bpf_link *link) 2457 { 2458 bpf_link_free_id(link->id); 2459 if (link->prog) { 2460 /* detach BPF program, clean up used resources */ 2461 link->ops->release(link); 2462 bpf_prog_put(link->prog); 2463 } 2464 /* free bpf_link and its containing memory */ 2465 link->ops->dealloc(link); 2466 } 2467 2468 static void bpf_link_put_deferred(struct work_struct *work) 2469 { 2470 struct bpf_link *link = container_of(work, struct bpf_link, work); 2471 2472 bpf_link_free(link); 2473 } 2474 2475 /* bpf_link_put can be called from atomic context, but ensures that resources 2476 * are freed from process context 2477 */ 2478 void bpf_link_put(struct bpf_link *link) 2479 { 2480 if (!atomic64_dec_and_test(&link->refcnt)) 2481 return; 2482 2483 if (in_atomic()) { 2484 INIT_WORK(&link->work, bpf_link_put_deferred); 2485 schedule_work(&link->work); 2486 } else { 2487 bpf_link_free(link); 2488 } 2489 } 2490 2491 static int bpf_link_release(struct inode *inode, struct file *filp) 2492 { 2493 struct bpf_link *link = filp->private_data; 2494 2495 bpf_link_put(link); 2496 return 0; 2497 } 2498 2499 #ifdef CONFIG_PROC_FS 2500 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 2501 #define BPF_MAP_TYPE(_id, _ops) 2502 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 2503 static const char *bpf_link_type_strs[] = { 2504 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 2505 #include <linux/bpf_types.h> 2506 }; 2507 #undef BPF_PROG_TYPE 2508 #undef BPF_MAP_TYPE 2509 #undef BPF_LINK_TYPE 2510 2511 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2512 { 2513 const struct bpf_link *link = filp->private_data; 2514 const struct bpf_prog *prog = link->prog; 2515 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2516 2517 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2518 seq_printf(m, 2519 "link_type:\t%s\n" 2520 "link_id:\t%u\n" 2521 "prog_tag:\t%s\n" 2522 "prog_id:\t%u\n", 2523 bpf_link_type_strs[link->type], 2524 link->id, 2525 prog_tag, 2526 prog->aux->id); 2527 if (link->ops->show_fdinfo) 2528 link->ops->show_fdinfo(link, m); 2529 } 2530 #endif 2531 2532 static const struct file_operations bpf_link_fops = { 2533 #ifdef CONFIG_PROC_FS 2534 .show_fdinfo = bpf_link_show_fdinfo, 2535 #endif 2536 .release = bpf_link_release, 2537 .read = bpf_dummy_read, 2538 .write = bpf_dummy_write, 2539 }; 2540 2541 static int bpf_link_alloc_id(struct bpf_link *link) 2542 { 2543 int id; 2544 2545 idr_preload(GFP_KERNEL); 2546 spin_lock_bh(&link_idr_lock); 2547 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 2548 spin_unlock_bh(&link_idr_lock); 2549 idr_preload_end(); 2550 2551 return id; 2552 } 2553 2554 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 2555 * reserving unused FD and allocating ID from link_idr. This is to be paired 2556 * with bpf_link_settle() to install FD and ID and expose bpf_link to 2557 * user-space, if bpf_link is successfully attached. If not, bpf_link and 2558 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 2559 * transient state is passed around in struct bpf_link_primer. 2560 * This is preferred way to create and initialize bpf_link, especially when 2561 * there are complicated and expensive operations inbetween creating bpf_link 2562 * itself and attaching it to BPF hook. By using bpf_link_prime() and 2563 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 2564 * expensive (and potentially failing) roll back operations in a rare case 2565 * that file, FD, or ID can't be allocated. 2566 */ 2567 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 2568 { 2569 struct file *file; 2570 int fd, id; 2571 2572 fd = get_unused_fd_flags(O_CLOEXEC); 2573 if (fd < 0) 2574 return fd; 2575 2576 2577 id = bpf_link_alloc_id(link); 2578 if (id < 0) { 2579 put_unused_fd(fd); 2580 return id; 2581 } 2582 2583 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2584 if (IS_ERR(file)) { 2585 bpf_link_free_id(id); 2586 put_unused_fd(fd); 2587 return PTR_ERR(file); 2588 } 2589 2590 primer->link = link; 2591 primer->file = file; 2592 primer->fd = fd; 2593 primer->id = id; 2594 return 0; 2595 } 2596 2597 int bpf_link_settle(struct bpf_link_primer *primer) 2598 { 2599 /* make bpf_link fetchable by ID */ 2600 spin_lock_bh(&link_idr_lock); 2601 primer->link->id = primer->id; 2602 spin_unlock_bh(&link_idr_lock); 2603 /* make bpf_link fetchable by FD */ 2604 fd_install(primer->fd, primer->file); 2605 /* pass through installed FD */ 2606 return primer->fd; 2607 } 2608 2609 int bpf_link_new_fd(struct bpf_link *link) 2610 { 2611 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2612 } 2613 2614 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2615 { 2616 struct fd f = fdget(ufd); 2617 struct bpf_link *link; 2618 2619 if (!f.file) 2620 return ERR_PTR(-EBADF); 2621 if (f.file->f_op != &bpf_link_fops) { 2622 fdput(f); 2623 return ERR_PTR(-EINVAL); 2624 } 2625 2626 link = f.file->private_data; 2627 bpf_link_inc(link); 2628 fdput(f); 2629 2630 return link; 2631 } 2632 2633 struct bpf_tracing_link { 2634 struct bpf_link link; 2635 enum bpf_attach_type attach_type; 2636 struct bpf_trampoline *trampoline; 2637 struct bpf_prog *tgt_prog; 2638 }; 2639 2640 static void bpf_tracing_link_release(struct bpf_link *link) 2641 { 2642 struct bpf_tracing_link *tr_link = 2643 container_of(link, struct bpf_tracing_link, link); 2644 2645 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, 2646 tr_link->trampoline)); 2647 2648 bpf_trampoline_put(tr_link->trampoline); 2649 2650 /* tgt_prog is NULL if target is a kernel function */ 2651 if (tr_link->tgt_prog) 2652 bpf_prog_put(tr_link->tgt_prog); 2653 } 2654 2655 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2656 { 2657 struct bpf_tracing_link *tr_link = 2658 container_of(link, struct bpf_tracing_link, link); 2659 2660 kfree(tr_link); 2661 } 2662 2663 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 2664 struct seq_file *seq) 2665 { 2666 struct bpf_tracing_link *tr_link = 2667 container_of(link, struct bpf_tracing_link, link); 2668 2669 seq_printf(seq, 2670 "attach_type:\t%d\n", 2671 tr_link->attach_type); 2672 } 2673 2674 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 2675 struct bpf_link_info *info) 2676 { 2677 struct bpf_tracing_link *tr_link = 2678 container_of(link, struct bpf_tracing_link, link); 2679 2680 info->tracing.attach_type = tr_link->attach_type; 2681 bpf_trampoline_unpack_key(tr_link->trampoline->key, 2682 &info->tracing.target_obj_id, 2683 &info->tracing.target_btf_id); 2684 2685 return 0; 2686 } 2687 2688 static const struct bpf_link_ops bpf_tracing_link_lops = { 2689 .release = bpf_tracing_link_release, 2690 .dealloc = bpf_tracing_link_dealloc, 2691 .show_fdinfo = bpf_tracing_link_show_fdinfo, 2692 .fill_link_info = bpf_tracing_link_fill_link_info, 2693 }; 2694 2695 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 2696 int tgt_prog_fd, 2697 u32 btf_id) 2698 { 2699 struct bpf_link_primer link_primer; 2700 struct bpf_prog *tgt_prog = NULL; 2701 struct bpf_trampoline *tr = NULL; 2702 struct bpf_tracing_link *link; 2703 u64 key = 0; 2704 int err; 2705 2706 switch (prog->type) { 2707 case BPF_PROG_TYPE_TRACING: 2708 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2709 prog->expected_attach_type != BPF_TRACE_FEXIT && 2710 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2711 err = -EINVAL; 2712 goto out_put_prog; 2713 } 2714 break; 2715 case BPF_PROG_TYPE_EXT: 2716 if (prog->expected_attach_type != 0) { 2717 err = -EINVAL; 2718 goto out_put_prog; 2719 } 2720 break; 2721 case BPF_PROG_TYPE_LSM: 2722 if (prog->expected_attach_type != BPF_LSM_MAC) { 2723 err = -EINVAL; 2724 goto out_put_prog; 2725 } 2726 break; 2727 default: 2728 err = -EINVAL; 2729 goto out_put_prog; 2730 } 2731 2732 if (!!tgt_prog_fd != !!btf_id) { 2733 err = -EINVAL; 2734 goto out_put_prog; 2735 } 2736 2737 if (tgt_prog_fd) { 2738 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */ 2739 if (prog->type != BPF_PROG_TYPE_EXT) { 2740 err = -EINVAL; 2741 goto out_put_prog; 2742 } 2743 2744 tgt_prog = bpf_prog_get(tgt_prog_fd); 2745 if (IS_ERR(tgt_prog)) { 2746 err = PTR_ERR(tgt_prog); 2747 tgt_prog = NULL; 2748 goto out_put_prog; 2749 } 2750 2751 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 2752 } 2753 2754 link = kzalloc(sizeof(*link), GFP_USER); 2755 if (!link) { 2756 err = -ENOMEM; 2757 goto out_put_prog; 2758 } 2759 bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, 2760 &bpf_tracing_link_lops, prog); 2761 link->attach_type = prog->expected_attach_type; 2762 2763 mutex_lock(&prog->aux->dst_mutex); 2764 2765 /* There are a few possible cases here: 2766 * 2767 * - if prog->aux->dst_trampoline is set, the program was just loaded 2768 * and not yet attached to anything, so we can use the values stored 2769 * in prog->aux 2770 * 2771 * - if prog->aux->dst_trampoline is NULL, the program has already been 2772 * attached to a target and its initial target was cleared (below) 2773 * 2774 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 2775 * target_btf_id using the link_create API. 2776 * 2777 * - if tgt_prog == NULL when this function was called using the old 2778 * raw_tracepoint_open API, and we need a target from prog->aux 2779 * 2780 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 2781 * was detached and is going for re-attachment. 2782 */ 2783 if (!prog->aux->dst_trampoline && !tgt_prog) { 2784 /* 2785 * Allow re-attach for TRACING and LSM programs. If it's 2786 * currently linked, bpf_trampoline_link_prog will fail. 2787 * EXT programs need to specify tgt_prog_fd, so they 2788 * re-attach in separate code path. 2789 */ 2790 if (prog->type != BPF_PROG_TYPE_TRACING && 2791 prog->type != BPF_PROG_TYPE_LSM) { 2792 err = -EINVAL; 2793 goto out_unlock; 2794 } 2795 btf_id = prog->aux->attach_btf_id; 2796 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 2797 } 2798 2799 if (!prog->aux->dst_trampoline || 2800 (key && key != prog->aux->dst_trampoline->key)) { 2801 /* If there is no saved target, or the specified target is 2802 * different from the destination specified at load time, we 2803 * need a new trampoline and a check for compatibility 2804 */ 2805 struct bpf_attach_target_info tgt_info = {}; 2806 2807 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 2808 &tgt_info); 2809 if (err) 2810 goto out_unlock; 2811 2812 tr = bpf_trampoline_get(key, &tgt_info); 2813 if (!tr) { 2814 err = -ENOMEM; 2815 goto out_unlock; 2816 } 2817 } else { 2818 /* The caller didn't specify a target, or the target was the 2819 * same as the destination supplied during program load. This 2820 * means we can reuse the trampoline and reference from program 2821 * load time, and there is no need to allocate a new one. This 2822 * can only happen once for any program, as the saved values in 2823 * prog->aux are cleared below. 2824 */ 2825 tr = prog->aux->dst_trampoline; 2826 tgt_prog = prog->aux->dst_prog; 2827 } 2828 2829 err = bpf_link_prime(&link->link, &link_primer); 2830 if (err) 2831 goto out_unlock; 2832 2833 err = bpf_trampoline_link_prog(prog, tr); 2834 if (err) { 2835 bpf_link_cleanup(&link_primer); 2836 link = NULL; 2837 goto out_unlock; 2838 } 2839 2840 link->tgt_prog = tgt_prog; 2841 link->trampoline = tr; 2842 2843 /* Always clear the trampoline and target prog from prog->aux to make 2844 * sure the original attach destination is not kept alive after a 2845 * program is (re-)attached to another target. 2846 */ 2847 if (prog->aux->dst_prog && 2848 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 2849 /* got extra prog ref from syscall, or attaching to different prog */ 2850 bpf_prog_put(prog->aux->dst_prog); 2851 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 2852 /* we allocated a new trampoline, so free the old one */ 2853 bpf_trampoline_put(prog->aux->dst_trampoline); 2854 2855 prog->aux->dst_prog = NULL; 2856 prog->aux->dst_trampoline = NULL; 2857 mutex_unlock(&prog->aux->dst_mutex); 2858 2859 return bpf_link_settle(&link_primer); 2860 out_unlock: 2861 if (tr && tr != prog->aux->dst_trampoline) 2862 bpf_trampoline_put(tr); 2863 mutex_unlock(&prog->aux->dst_mutex); 2864 kfree(link); 2865 out_put_prog: 2866 if (tgt_prog_fd && tgt_prog) 2867 bpf_prog_put(tgt_prog); 2868 return err; 2869 } 2870 2871 struct bpf_raw_tp_link { 2872 struct bpf_link link; 2873 struct bpf_raw_event_map *btp; 2874 }; 2875 2876 static void bpf_raw_tp_link_release(struct bpf_link *link) 2877 { 2878 struct bpf_raw_tp_link *raw_tp = 2879 container_of(link, struct bpf_raw_tp_link, link); 2880 2881 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2882 bpf_put_raw_tracepoint(raw_tp->btp); 2883 } 2884 2885 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2886 { 2887 struct bpf_raw_tp_link *raw_tp = 2888 container_of(link, struct bpf_raw_tp_link, link); 2889 2890 kfree(raw_tp); 2891 } 2892 2893 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 2894 struct seq_file *seq) 2895 { 2896 struct bpf_raw_tp_link *raw_tp_link = 2897 container_of(link, struct bpf_raw_tp_link, link); 2898 2899 seq_printf(seq, 2900 "tp_name:\t%s\n", 2901 raw_tp_link->btp->tp->name); 2902 } 2903 2904 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 2905 struct bpf_link_info *info) 2906 { 2907 struct bpf_raw_tp_link *raw_tp_link = 2908 container_of(link, struct bpf_raw_tp_link, link); 2909 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 2910 const char *tp_name = raw_tp_link->btp->tp->name; 2911 u32 ulen = info->raw_tracepoint.tp_name_len; 2912 size_t tp_len = strlen(tp_name); 2913 2914 if (!ulen ^ !ubuf) 2915 return -EINVAL; 2916 2917 info->raw_tracepoint.tp_name_len = tp_len + 1; 2918 2919 if (!ubuf) 2920 return 0; 2921 2922 if (ulen >= tp_len + 1) { 2923 if (copy_to_user(ubuf, tp_name, tp_len + 1)) 2924 return -EFAULT; 2925 } else { 2926 char zero = '\0'; 2927 2928 if (copy_to_user(ubuf, tp_name, ulen - 1)) 2929 return -EFAULT; 2930 if (put_user(zero, ubuf + ulen - 1)) 2931 return -EFAULT; 2932 return -ENOSPC; 2933 } 2934 2935 return 0; 2936 } 2937 2938 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 2939 .release = bpf_raw_tp_link_release, 2940 .dealloc = bpf_raw_tp_link_dealloc, 2941 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 2942 .fill_link_info = bpf_raw_tp_link_fill_link_info, 2943 }; 2944 2945 #ifdef CONFIG_PERF_EVENTS 2946 struct bpf_perf_link { 2947 struct bpf_link link; 2948 struct file *perf_file; 2949 }; 2950 2951 static void bpf_perf_link_release(struct bpf_link *link) 2952 { 2953 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2954 struct perf_event *event = perf_link->perf_file->private_data; 2955 2956 perf_event_free_bpf_prog(event); 2957 fput(perf_link->perf_file); 2958 } 2959 2960 static void bpf_perf_link_dealloc(struct bpf_link *link) 2961 { 2962 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2963 2964 kfree(perf_link); 2965 } 2966 2967 static const struct bpf_link_ops bpf_perf_link_lops = { 2968 .release = bpf_perf_link_release, 2969 .dealloc = bpf_perf_link_dealloc, 2970 }; 2971 2972 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 2973 { 2974 struct bpf_link_primer link_primer; 2975 struct bpf_perf_link *link; 2976 struct perf_event *event; 2977 struct file *perf_file; 2978 int err; 2979 2980 if (attr->link_create.flags) 2981 return -EINVAL; 2982 2983 perf_file = perf_event_get(attr->link_create.target_fd); 2984 if (IS_ERR(perf_file)) 2985 return PTR_ERR(perf_file); 2986 2987 link = kzalloc(sizeof(*link), GFP_USER); 2988 if (!link) { 2989 err = -ENOMEM; 2990 goto out_put_file; 2991 } 2992 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 2993 link->perf_file = perf_file; 2994 2995 err = bpf_link_prime(&link->link, &link_primer); 2996 if (err) { 2997 kfree(link); 2998 goto out_put_file; 2999 } 3000 3001 event = perf_file->private_data; 3002 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3003 if (err) { 3004 bpf_link_cleanup(&link_primer); 3005 goto out_put_file; 3006 } 3007 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3008 bpf_prog_inc(prog); 3009 3010 return bpf_link_settle(&link_primer); 3011 3012 out_put_file: 3013 fput(perf_file); 3014 return err; 3015 } 3016 #endif /* CONFIG_PERF_EVENTS */ 3017 3018 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 3019 3020 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3021 { 3022 struct bpf_link_primer link_primer; 3023 struct bpf_raw_tp_link *link; 3024 struct bpf_raw_event_map *btp; 3025 struct bpf_prog *prog; 3026 const char *tp_name; 3027 char buf[128]; 3028 int err; 3029 3030 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3031 return -EINVAL; 3032 3033 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3034 if (IS_ERR(prog)) 3035 return PTR_ERR(prog); 3036 3037 switch (prog->type) { 3038 case BPF_PROG_TYPE_TRACING: 3039 case BPF_PROG_TYPE_EXT: 3040 case BPF_PROG_TYPE_LSM: 3041 if (attr->raw_tracepoint.name) { 3042 /* The attach point for this category of programs 3043 * should be specified via btf_id during program load. 3044 */ 3045 err = -EINVAL; 3046 goto out_put_prog; 3047 } 3048 if (prog->type == BPF_PROG_TYPE_TRACING && 3049 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3050 tp_name = prog->aux->attach_func_name; 3051 break; 3052 } 3053 err = bpf_tracing_prog_attach(prog, 0, 0); 3054 if (err >= 0) 3055 return err; 3056 goto out_put_prog; 3057 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3058 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3059 if (strncpy_from_user(buf, 3060 u64_to_user_ptr(attr->raw_tracepoint.name), 3061 sizeof(buf) - 1) < 0) { 3062 err = -EFAULT; 3063 goto out_put_prog; 3064 } 3065 buf[sizeof(buf) - 1] = 0; 3066 tp_name = buf; 3067 break; 3068 default: 3069 err = -EINVAL; 3070 goto out_put_prog; 3071 } 3072 3073 btp = bpf_get_raw_tracepoint(tp_name); 3074 if (!btp) { 3075 err = -ENOENT; 3076 goto out_put_prog; 3077 } 3078 3079 link = kzalloc(sizeof(*link), GFP_USER); 3080 if (!link) { 3081 err = -ENOMEM; 3082 goto out_put_btp; 3083 } 3084 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3085 &bpf_raw_tp_link_lops, prog); 3086 link->btp = btp; 3087 3088 err = bpf_link_prime(&link->link, &link_primer); 3089 if (err) { 3090 kfree(link); 3091 goto out_put_btp; 3092 } 3093 3094 err = bpf_probe_register(link->btp, prog); 3095 if (err) { 3096 bpf_link_cleanup(&link_primer); 3097 goto out_put_btp; 3098 } 3099 3100 return bpf_link_settle(&link_primer); 3101 3102 out_put_btp: 3103 bpf_put_raw_tracepoint(btp); 3104 out_put_prog: 3105 bpf_prog_put(prog); 3106 return err; 3107 } 3108 3109 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3110 enum bpf_attach_type attach_type) 3111 { 3112 switch (prog->type) { 3113 case BPF_PROG_TYPE_CGROUP_SOCK: 3114 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3115 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3116 case BPF_PROG_TYPE_SK_LOOKUP: 3117 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3118 case BPF_PROG_TYPE_CGROUP_SKB: 3119 if (!capable(CAP_NET_ADMIN)) 3120 /* cg-skb progs can be loaded by unpriv user. 3121 * check permissions at attach time. 3122 */ 3123 return -EPERM; 3124 return prog->enforce_expected_attach_type && 3125 prog->expected_attach_type != attach_type ? 3126 -EINVAL : 0; 3127 default: 3128 return 0; 3129 } 3130 } 3131 3132 static enum bpf_prog_type 3133 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3134 { 3135 switch (attach_type) { 3136 case BPF_CGROUP_INET_INGRESS: 3137 case BPF_CGROUP_INET_EGRESS: 3138 return BPF_PROG_TYPE_CGROUP_SKB; 3139 case BPF_CGROUP_INET_SOCK_CREATE: 3140 case BPF_CGROUP_INET_SOCK_RELEASE: 3141 case BPF_CGROUP_INET4_POST_BIND: 3142 case BPF_CGROUP_INET6_POST_BIND: 3143 return BPF_PROG_TYPE_CGROUP_SOCK; 3144 case BPF_CGROUP_INET4_BIND: 3145 case BPF_CGROUP_INET6_BIND: 3146 case BPF_CGROUP_INET4_CONNECT: 3147 case BPF_CGROUP_INET6_CONNECT: 3148 case BPF_CGROUP_INET4_GETPEERNAME: 3149 case BPF_CGROUP_INET6_GETPEERNAME: 3150 case BPF_CGROUP_INET4_GETSOCKNAME: 3151 case BPF_CGROUP_INET6_GETSOCKNAME: 3152 case BPF_CGROUP_UDP4_SENDMSG: 3153 case BPF_CGROUP_UDP6_SENDMSG: 3154 case BPF_CGROUP_UDP4_RECVMSG: 3155 case BPF_CGROUP_UDP6_RECVMSG: 3156 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3157 case BPF_CGROUP_SOCK_OPS: 3158 return BPF_PROG_TYPE_SOCK_OPS; 3159 case BPF_CGROUP_DEVICE: 3160 return BPF_PROG_TYPE_CGROUP_DEVICE; 3161 case BPF_SK_MSG_VERDICT: 3162 return BPF_PROG_TYPE_SK_MSG; 3163 case BPF_SK_SKB_STREAM_PARSER: 3164 case BPF_SK_SKB_STREAM_VERDICT: 3165 case BPF_SK_SKB_VERDICT: 3166 return BPF_PROG_TYPE_SK_SKB; 3167 case BPF_LIRC_MODE2: 3168 return BPF_PROG_TYPE_LIRC_MODE2; 3169 case BPF_FLOW_DISSECTOR: 3170 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3171 case BPF_CGROUP_SYSCTL: 3172 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3173 case BPF_CGROUP_GETSOCKOPT: 3174 case BPF_CGROUP_SETSOCKOPT: 3175 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3176 case BPF_TRACE_ITER: 3177 return BPF_PROG_TYPE_TRACING; 3178 case BPF_SK_LOOKUP: 3179 return BPF_PROG_TYPE_SK_LOOKUP; 3180 case BPF_XDP: 3181 return BPF_PROG_TYPE_XDP; 3182 default: 3183 return BPF_PROG_TYPE_UNSPEC; 3184 } 3185 } 3186 3187 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 3188 3189 #define BPF_F_ATTACH_MASK \ 3190 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 3191 3192 static int bpf_prog_attach(const union bpf_attr *attr) 3193 { 3194 enum bpf_prog_type ptype; 3195 struct bpf_prog *prog; 3196 int ret; 3197 3198 if (CHECK_ATTR(BPF_PROG_ATTACH)) 3199 return -EINVAL; 3200 3201 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 3202 return -EINVAL; 3203 3204 ptype = attach_type_to_prog_type(attr->attach_type); 3205 if (ptype == BPF_PROG_TYPE_UNSPEC) 3206 return -EINVAL; 3207 3208 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 3209 if (IS_ERR(prog)) 3210 return PTR_ERR(prog); 3211 3212 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 3213 bpf_prog_put(prog); 3214 return -EINVAL; 3215 } 3216 3217 switch (ptype) { 3218 case BPF_PROG_TYPE_SK_SKB: 3219 case BPF_PROG_TYPE_SK_MSG: 3220 ret = sock_map_get_from_fd(attr, prog); 3221 break; 3222 case BPF_PROG_TYPE_LIRC_MODE2: 3223 ret = lirc_prog_attach(attr, prog); 3224 break; 3225 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3226 ret = netns_bpf_prog_attach(attr, prog); 3227 break; 3228 case BPF_PROG_TYPE_CGROUP_DEVICE: 3229 case BPF_PROG_TYPE_CGROUP_SKB: 3230 case BPF_PROG_TYPE_CGROUP_SOCK: 3231 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3232 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3233 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3234 case BPF_PROG_TYPE_SOCK_OPS: 3235 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 3236 break; 3237 default: 3238 ret = -EINVAL; 3239 } 3240 3241 if (ret) 3242 bpf_prog_put(prog); 3243 return ret; 3244 } 3245 3246 #define BPF_PROG_DETACH_LAST_FIELD attach_type 3247 3248 static int bpf_prog_detach(const union bpf_attr *attr) 3249 { 3250 enum bpf_prog_type ptype; 3251 3252 if (CHECK_ATTR(BPF_PROG_DETACH)) 3253 return -EINVAL; 3254 3255 ptype = attach_type_to_prog_type(attr->attach_type); 3256 3257 switch (ptype) { 3258 case BPF_PROG_TYPE_SK_MSG: 3259 case BPF_PROG_TYPE_SK_SKB: 3260 return sock_map_prog_detach(attr, ptype); 3261 case BPF_PROG_TYPE_LIRC_MODE2: 3262 return lirc_prog_detach(attr); 3263 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3264 return netns_bpf_prog_detach(attr, ptype); 3265 case BPF_PROG_TYPE_CGROUP_DEVICE: 3266 case BPF_PROG_TYPE_CGROUP_SKB: 3267 case BPF_PROG_TYPE_CGROUP_SOCK: 3268 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3269 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3270 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3271 case BPF_PROG_TYPE_SOCK_OPS: 3272 return cgroup_bpf_prog_detach(attr, ptype); 3273 default: 3274 return -EINVAL; 3275 } 3276 } 3277 3278 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 3279 3280 static int bpf_prog_query(const union bpf_attr *attr, 3281 union bpf_attr __user *uattr) 3282 { 3283 if (!capable(CAP_NET_ADMIN)) 3284 return -EPERM; 3285 if (CHECK_ATTR(BPF_PROG_QUERY)) 3286 return -EINVAL; 3287 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 3288 return -EINVAL; 3289 3290 switch (attr->query.attach_type) { 3291 case BPF_CGROUP_INET_INGRESS: 3292 case BPF_CGROUP_INET_EGRESS: 3293 case BPF_CGROUP_INET_SOCK_CREATE: 3294 case BPF_CGROUP_INET_SOCK_RELEASE: 3295 case BPF_CGROUP_INET4_BIND: 3296 case BPF_CGROUP_INET6_BIND: 3297 case BPF_CGROUP_INET4_POST_BIND: 3298 case BPF_CGROUP_INET6_POST_BIND: 3299 case BPF_CGROUP_INET4_CONNECT: 3300 case BPF_CGROUP_INET6_CONNECT: 3301 case BPF_CGROUP_INET4_GETPEERNAME: 3302 case BPF_CGROUP_INET6_GETPEERNAME: 3303 case BPF_CGROUP_INET4_GETSOCKNAME: 3304 case BPF_CGROUP_INET6_GETSOCKNAME: 3305 case BPF_CGROUP_UDP4_SENDMSG: 3306 case BPF_CGROUP_UDP6_SENDMSG: 3307 case BPF_CGROUP_UDP4_RECVMSG: 3308 case BPF_CGROUP_UDP6_RECVMSG: 3309 case BPF_CGROUP_SOCK_OPS: 3310 case BPF_CGROUP_DEVICE: 3311 case BPF_CGROUP_SYSCTL: 3312 case BPF_CGROUP_GETSOCKOPT: 3313 case BPF_CGROUP_SETSOCKOPT: 3314 return cgroup_bpf_prog_query(attr, uattr); 3315 case BPF_LIRC_MODE2: 3316 return lirc_prog_query(attr, uattr); 3317 case BPF_FLOW_DISSECTOR: 3318 case BPF_SK_LOOKUP: 3319 return netns_bpf_prog_query(attr, uattr); 3320 default: 3321 return -EINVAL; 3322 } 3323 } 3324 3325 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu 3326 3327 static int bpf_prog_test_run(const union bpf_attr *attr, 3328 union bpf_attr __user *uattr) 3329 { 3330 struct bpf_prog *prog; 3331 int ret = -ENOTSUPP; 3332 3333 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 3334 return -EINVAL; 3335 3336 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 3337 (!attr->test.ctx_size_in && attr->test.ctx_in)) 3338 return -EINVAL; 3339 3340 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 3341 (!attr->test.ctx_size_out && attr->test.ctx_out)) 3342 return -EINVAL; 3343 3344 prog = bpf_prog_get(attr->test.prog_fd); 3345 if (IS_ERR(prog)) 3346 return PTR_ERR(prog); 3347 3348 if (prog->aux->ops->test_run) 3349 ret = prog->aux->ops->test_run(prog, attr, uattr); 3350 3351 bpf_prog_put(prog); 3352 return ret; 3353 } 3354 3355 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 3356 3357 static int bpf_obj_get_next_id(const union bpf_attr *attr, 3358 union bpf_attr __user *uattr, 3359 struct idr *idr, 3360 spinlock_t *lock) 3361 { 3362 u32 next_id = attr->start_id; 3363 int err = 0; 3364 3365 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 3366 return -EINVAL; 3367 3368 if (!capable(CAP_SYS_ADMIN)) 3369 return -EPERM; 3370 3371 next_id++; 3372 spin_lock_bh(lock); 3373 if (!idr_get_next(idr, &next_id)) 3374 err = -ENOENT; 3375 spin_unlock_bh(lock); 3376 3377 if (!err) 3378 err = put_user(next_id, &uattr->next_id); 3379 3380 return err; 3381 } 3382 3383 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 3384 { 3385 struct bpf_map *map; 3386 3387 spin_lock_bh(&map_idr_lock); 3388 again: 3389 map = idr_get_next(&map_idr, id); 3390 if (map) { 3391 map = __bpf_map_inc_not_zero(map, false); 3392 if (IS_ERR(map)) { 3393 (*id)++; 3394 goto again; 3395 } 3396 } 3397 spin_unlock_bh(&map_idr_lock); 3398 3399 return map; 3400 } 3401 3402 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 3403 { 3404 struct bpf_prog *prog; 3405 3406 spin_lock_bh(&prog_idr_lock); 3407 again: 3408 prog = idr_get_next(&prog_idr, id); 3409 if (prog) { 3410 prog = bpf_prog_inc_not_zero(prog); 3411 if (IS_ERR(prog)) { 3412 (*id)++; 3413 goto again; 3414 } 3415 } 3416 spin_unlock_bh(&prog_idr_lock); 3417 3418 return prog; 3419 } 3420 3421 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 3422 3423 struct bpf_prog *bpf_prog_by_id(u32 id) 3424 { 3425 struct bpf_prog *prog; 3426 3427 if (!id) 3428 return ERR_PTR(-ENOENT); 3429 3430 spin_lock_bh(&prog_idr_lock); 3431 prog = idr_find(&prog_idr, id); 3432 if (prog) 3433 prog = bpf_prog_inc_not_zero(prog); 3434 else 3435 prog = ERR_PTR(-ENOENT); 3436 spin_unlock_bh(&prog_idr_lock); 3437 return prog; 3438 } 3439 3440 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 3441 { 3442 struct bpf_prog *prog; 3443 u32 id = attr->prog_id; 3444 int fd; 3445 3446 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 3447 return -EINVAL; 3448 3449 if (!capable(CAP_SYS_ADMIN)) 3450 return -EPERM; 3451 3452 prog = bpf_prog_by_id(id); 3453 if (IS_ERR(prog)) 3454 return PTR_ERR(prog); 3455 3456 fd = bpf_prog_new_fd(prog); 3457 if (fd < 0) 3458 bpf_prog_put(prog); 3459 3460 return fd; 3461 } 3462 3463 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 3464 3465 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 3466 { 3467 struct bpf_map *map; 3468 u32 id = attr->map_id; 3469 int f_flags; 3470 int fd; 3471 3472 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 3473 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 3474 return -EINVAL; 3475 3476 if (!capable(CAP_SYS_ADMIN)) 3477 return -EPERM; 3478 3479 f_flags = bpf_get_file_flag(attr->open_flags); 3480 if (f_flags < 0) 3481 return f_flags; 3482 3483 spin_lock_bh(&map_idr_lock); 3484 map = idr_find(&map_idr, id); 3485 if (map) 3486 map = __bpf_map_inc_not_zero(map, true); 3487 else 3488 map = ERR_PTR(-ENOENT); 3489 spin_unlock_bh(&map_idr_lock); 3490 3491 if (IS_ERR(map)) 3492 return PTR_ERR(map); 3493 3494 fd = bpf_map_new_fd(map, f_flags); 3495 if (fd < 0) 3496 bpf_map_put_with_uref(map); 3497 3498 return fd; 3499 } 3500 3501 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 3502 unsigned long addr, u32 *off, 3503 u32 *type) 3504 { 3505 const struct bpf_map *map; 3506 int i; 3507 3508 mutex_lock(&prog->aux->used_maps_mutex); 3509 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 3510 map = prog->aux->used_maps[i]; 3511 if (map == (void *)addr) { 3512 *type = BPF_PSEUDO_MAP_FD; 3513 goto out; 3514 } 3515 if (!map->ops->map_direct_value_meta) 3516 continue; 3517 if (!map->ops->map_direct_value_meta(map, addr, off)) { 3518 *type = BPF_PSEUDO_MAP_VALUE; 3519 goto out; 3520 } 3521 } 3522 map = NULL; 3523 3524 out: 3525 mutex_unlock(&prog->aux->used_maps_mutex); 3526 return map; 3527 } 3528 3529 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 3530 const struct cred *f_cred) 3531 { 3532 const struct bpf_map *map; 3533 struct bpf_insn *insns; 3534 u32 off, type; 3535 u64 imm; 3536 u8 code; 3537 int i; 3538 3539 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 3540 GFP_USER); 3541 if (!insns) 3542 return insns; 3543 3544 for (i = 0; i < prog->len; i++) { 3545 code = insns[i].code; 3546 3547 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 3548 insns[i].code = BPF_JMP | BPF_CALL; 3549 insns[i].imm = BPF_FUNC_tail_call; 3550 /* fall-through */ 3551 } 3552 if (code == (BPF_JMP | BPF_CALL) || 3553 code == (BPF_JMP | BPF_CALL_ARGS)) { 3554 if (code == (BPF_JMP | BPF_CALL_ARGS)) 3555 insns[i].code = BPF_JMP | BPF_CALL; 3556 if (!bpf_dump_raw_ok(f_cred)) 3557 insns[i].imm = 0; 3558 continue; 3559 } 3560 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 3561 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 3562 continue; 3563 } 3564 3565 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 3566 continue; 3567 3568 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 3569 map = bpf_map_from_imm(prog, imm, &off, &type); 3570 if (map) { 3571 insns[i].src_reg = type; 3572 insns[i].imm = map->id; 3573 insns[i + 1].imm = off; 3574 continue; 3575 } 3576 } 3577 3578 return insns; 3579 } 3580 3581 static int set_info_rec_size(struct bpf_prog_info *info) 3582 { 3583 /* 3584 * Ensure info.*_rec_size is the same as kernel expected size 3585 * 3586 * or 3587 * 3588 * Only allow zero *_rec_size if both _rec_size and _cnt are 3589 * zero. In this case, the kernel will set the expected 3590 * _rec_size back to the info. 3591 */ 3592 3593 if ((info->nr_func_info || info->func_info_rec_size) && 3594 info->func_info_rec_size != sizeof(struct bpf_func_info)) 3595 return -EINVAL; 3596 3597 if ((info->nr_line_info || info->line_info_rec_size) && 3598 info->line_info_rec_size != sizeof(struct bpf_line_info)) 3599 return -EINVAL; 3600 3601 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 3602 info->jited_line_info_rec_size != sizeof(__u64)) 3603 return -EINVAL; 3604 3605 info->func_info_rec_size = sizeof(struct bpf_func_info); 3606 info->line_info_rec_size = sizeof(struct bpf_line_info); 3607 info->jited_line_info_rec_size = sizeof(__u64); 3608 3609 return 0; 3610 } 3611 3612 static int bpf_prog_get_info_by_fd(struct file *file, 3613 struct bpf_prog *prog, 3614 const union bpf_attr *attr, 3615 union bpf_attr __user *uattr) 3616 { 3617 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3618 struct bpf_prog_info info; 3619 u32 info_len = attr->info.info_len; 3620 struct bpf_prog_kstats stats; 3621 char __user *uinsns; 3622 u32 ulen; 3623 int err; 3624 3625 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3626 if (err) 3627 return err; 3628 info_len = min_t(u32, sizeof(info), info_len); 3629 3630 memset(&info, 0, sizeof(info)); 3631 if (copy_from_user(&info, uinfo, info_len)) 3632 return -EFAULT; 3633 3634 info.type = prog->type; 3635 info.id = prog->aux->id; 3636 info.load_time = prog->aux->load_time; 3637 info.created_by_uid = from_kuid_munged(current_user_ns(), 3638 prog->aux->user->uid); 3639 info.gpl_compatible = prog->gpl_compatible; 3640 3641 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3642 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3643 3644 mutex_lock(&prog->aux->used_maps_mutex); 3645 ulen = info.nr_map_ids; 3646 info.nr_map_ids = prog->aux->used_map_cnt; 3647 ulen = min_t(u32, info.nr_map_ids, ulen); 3648 if (ulen) { 3649 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3650 u32 i; 3651 3652 for (i = 0; i < ulen; i++) 3653 if (put_user(prog->aux->used_maps[i]->id, 3654 &user_map_ids[i])) { 3655 mutex_unlock(&prog->aux->used_maps_mutex); 3656 return -EFAULT; 3657 } 3658 } 3659 mutex_unlock(&prog->aux->used_maps_mutex); 3660 3661 err = set_info_rec_size(&info); 3662 if (err) 3663 return err; 3664 3665 bpf_prog_get_stats(prog, &stats); 3666 info.run_time_ns = stats.nsecs; 3667 info.run_cnt = stats.cnt; 3668 info.recursion_misses = stats.misses; 3669 3670 info.verified_insns = prog->aux->verified_insns; 3671 3672 if (!bpf_capable()) { 3673 info.jited_prog_len = 0; 3674 info.xlated_prog_len = 0; 3675 info.nr_jited_ksyms = 0; 3676 info.nr_jited_func_lens = 0; 3677 info.nr_func_info = 0; 3678 info.nr_line_info = 0; 3679 info.nr_jited_line_info = 0; 3680 goto done; 3681 } 3682 3683 ulen = info.xlated_prog_len; 3684 info.xlated_prog_len = bpf_prog_insn_size(prog); 3685 if (info.xlated_prog_len && ulen) { 3686 struct bpf_insn *insns_sanitized; 3687 bool fault; 3688 3689 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 3690 info.xlated_prog_insns = 0; 3691 goto done; 3692 } 3693 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 3694 if (!insns_sanitized) 3695 return -ENOMEM; 3696 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3697 ulen = min_t(u32, info.xlated_prog_len, ulen); 3698 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3699 kfree(insns_sanitized); 3700 if (fault) 3701 return -EFAULT; 3702 } 3703 3704 if (bpf_prog_is_dev_bound(prog->aux)) { 3705 err = bpf_prog_offload_info_fill(&info, prog); 3706 if (err) 3707 return err; 3708 goto done; 3709 } 3710 3711 /* NOTE: the following code is supposed to be skipped for offload. 3712 * bpf_prog_offload_info_fill() is the place to fill similar fields 3713 * for offload. 3714 */ 3715 ulen = info.jited_prog_len; 3716 if (prog->aux->func_cnt) { 3717 u32 i; 3718 3719 info.jited_prog_len = 0; 3720 for (i = 0; i < prog->aux->func_cnt; i++) 3721 info.jited_prog_len += prog->aux->func[i]->jited_len; 3722 } else { 3723 info.jited_prog_len = prog->jited_len; 3724 } 3725 3726 if (info.jited_prog_len && ulen) { 3727 if (bpf_dump_raw_ok(file->f_cred)) { 3728 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3729 ulen = min_t(u32, info.jited_prog_len, ulen); 3730 3731 /* for multi-function programs, copy the JITed 3732 * instructions for all the functions 3733 */ 3734 if (prog->aux->func_cnt) { 3735 u32 len, free, i; 3736 u8 *img; 3737 3738 free = ulen; 3739 for (i = 0; i < prog->aux->func_cnt; i++) { 3740 len = prog->aux->func[i]->jited_len; 3741 len = min_t(u32, len, free); 3742 img = (u8 *) prog->aux->func[i]->bpf_func; 3743 if (copy_to_user(uinsns, img, len)) 3744 return -EFAULT; 3745 uinsns += len; 3746 free -= len; 3747 if (!free) 3748 break; 3749 } 3750 } else { 3751 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3752 return -EFAULT; 3753 } 3754 } else { 3755 info.jited_prog_insns = 0; 3756 } 3757 } 3758 3759 ulen = info.nr_jited_ksyms; 3760 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3761 if (ulen) { 3762 if (bpf_dump_raw_ok(file->f_cred)) { 3763 unsigned long ksym_addr; 3764 u64 __user *user_ksyms; 3765 u32 i; 3766 3767 /* copy the address of the kernel symbol 3768 * corresponding to each function 3769 */ 3770 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3771 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3772 if (prog->aux->func_cnt) { 3773 for (i = 0; i < ulen; i++) { 3774 ksym_addr = (unsigned long) 3775 prog->aux->func[i]->bpf_func; 3776 if (put_user((u64) ksym_addr, 3777 &user_ksyms[i])) 3778 return -EFAULT; 3779 } 3780 } else { 3781 ksym_addr = (unsigned long) prog->bpf_func; 3782 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3783 return -EFAULT; 3784 } 3785 } else { 3786 info.jited_ksyms = 0; 3787 } 3788 } 3789 3790 ulen = info.nr_jited_func_lens; 3791 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3792 if (ulen) { 3793 if (bpf_dump_raw_ok(file->f_cred)) { 3794 u32 __user *user_lens; 3795 u32 func_len, i; 3796 3797 /* copy the JITed image lengths for each function */ 3798 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3799 user_lens = u64_to_user_ptr(info.jited_func_lens); 3800 if (prog->aux->func_cnt) { 3801 for (i = 0; i < ulen; i++) { 3802 func_len = 3803 prog->aux->func[i]->jited_len; 3804 if (put_user(func_len, &user_lens[i])) 3805 return -EFAULT; 3806 } 3807 } else { 3808 func_len = prog->jited_len; 3809 if (put_user(func_len, &user_lens[0])) 3810 return -EFAULT; 3811 } 3812 } else { 3813 info.jited_func_lens = 0; 3814 } 3815 } 3816 3817 if (prog->aux->btf) 3818 info.btf_id = btf_obj_id(prog->aux->btf); 3819 3820 ulen = info.nr_func_info; 3821 info.nr_func_info = prog->aux->func_info_cnt; 3822 if (info.nr_func_info && ulen) { 3823 char __user *user_finfo; 3824 3825 user_finfo = u64_to_user_ptr(info.func_info); 3826 ulen = min_t(u32, info.nr_func_info, ulen); 3827 if (copy_to_user(user_finfo, prog->aux->func_info, 3828 info.func_info_rec_size * ulen)) 3829 return -EFAULT; 3830 } 3831 3832 ulen = info.nr_line_info; 3833 info.nr_line_info = prog->aux->nr_linfo; 3834 if (info.nr_line_info && ulen) { 3835 __u8 __user *user_linfo; 3836 3837 user_linfo = u64_to_user_ptr(info.line_info); 3838 ulen = min_t(u32, info.nr_line_info, ulen); 3839 if (copy_to_user(user_linfo, prog->aux->linfo, 3840 info.line_info_rec_size * ulen)) 3841 return -EFAULT; 3842 } 3843 3844 ulen = info.nr_jited_line_info; 3845 if (prog->aux->jited_linfo) 3846 info.nr_jited_line_info = prog->aux->nr_linfo; 3847 else 3848 info.nr_jited_line_info = 0; 3849 if (info.nr_jited_line_info && ulen) { 3850 if (bpf_dump_raw_ok(file->f_cred)) { 3851 __u64 __user *user_linfo; 3852 u32 i; 3853 3854 user_linfo = u64_to_user_ptr(info.jited_line_info); 3855 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3856 for (i = 0; i < ulen; i++) { 3857 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3858 &user_linfo[i])) 3859 return -EFAULT; 3860 } 3861 } else { 3862 info.jited_line_info = 0; 3863 } 3864 } 3865 3866 ulen = info.nr_prog_tags; 3867 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3868 if (ulen) { 3869 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3870 u32 i; 3871 3872 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3873 ulen = min_t(u32, info.nr_prog_tags, ulen); 3874 if (prog->aux->func_cnt) { 3875 for (i = 0; i < ulen; i++) { 3876 if (copy_to_user(user_prog_tags[i], 3877 prog->aux->func[i]->tag, 3878 BPF_TAG_SIZE)) 3879 return -EFAULT; 3880 } 3881 } else { 3882 if (copy_to_user(user_prog_tags[0], 3883 prog->tag, BPF_TAG_SIZE)) 3884 return -EFAULT; 3885 } 3886 } 3887 3888 done: 3889 if (copy_to_user(uinfo, &info, info_len) || 3890 put_user(info_len, &uattr->info.info_len)) 3891 return -EFAULT; 3892 3893 return 0; 3894 } 3895 3896 static int bpf_map_get_info_by_fd(struct file *file, 3897 struct bpf_map *map, 3898 const union bpf_attr *attr, 3899 union bpf_attr __user *uattr) 3900 { 3901 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3902 struct bpf_map_info info; 3903 u32 info_len = attr->info.info_len; 3904 int err; 3905 3906 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3907 if (err) 3908 return err; 3909 info_len = min_t(u32, sizeof(info), info_len); 3910 3911 memset(&info, 0, sizeof(info)); 3912 info.type = map->map_type; 3913 info.id = map->id; 3914 info.key_size = map->key_size; 3915 info.value_size = map->value_size; 3916 info.max_entries = map->max_entries; 3917 info.map_flags = map->map_flags; 3918 info.map_extra = map->map_extra; 3919 memcpy(info.name, map->name, sizeof(map->name)); 3920 3921 if (map->btf) { 3922 info.btf_id = btf_obj_id(map->btf); 3923 info.btf_key_type_id = map->btf_key_type_id; 3924 info.btf_value_type_id = map->btf_value_type_id; 3925 } 3926 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3927 3928 if (bpf_map_is_dev_bound(map)) { 3929 err = bpf_map_offload_info_fill(&info, map); 3930 if (err) 3931 return err; 3932 } 3933 3934 if (copy_to_user(uinfo, &info, info_len) || 3935 put_user(info_len, &uattr->info.info_len)) 3936 return -EFAULT; 3937 3938 return 0; 3939 } 3940 3941 static int bpf_btf_get_info_by_fd(struct file *file, 3942 struct btf *btf, 3943 const union bpf_attr *attr, 3944 union bpf_attr __user *uattr) 3945 { 3946 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3947 u32 info_len = attr->info.info_len; 3948 int err; 3949 3950 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 3951 if (err) 3952 return err; 3953 3954 return btf_get_info_by_fd(btf, attr, uattr); 3955 } 3956 3957 static int bpf_link_get_info_by_fd(struct file *file, 3958 struct bpf_link *link, 3959 const union bpf_attr *attr, 3960 union bpf_attr __user *uattr) 3961 { 3962 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3963 struct bpf_link_info info; 3964 u32 info_len = attr->info.info_len; 3965 int err; 3966 3967 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3968 if (err) 3969 return err; 3970 info_len = min_t(u32, sizeof(info), info_len); 3971 3972 memset(&info, 0, sizeof(info)); 3973 if (copy_from_user(&info, uinfo, info_len)) 3974 return -EFAULT; 3975 3976 info.type = link->type; 3977 info.id = link->id; 3978 info.prog_id = link->prog->aux->id; 3979 3980 if (link->ops->fill_link_info) { 3981 err = link->ops->fill_link_info(link, &info); 3982 if (err) 3983 return err; 3984 } 3985 3986 if (copy_to_user(uinfo, &info, info_len) || 3987 put_user(info_len, &uattr->info.info_len)) 3988 return -EFAULT; 3989 3990 return 0; 3991 } 3992 3993 3994 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 3995 3996 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 3997 union bpf_attr __user *uattr) 3998 { 3999 int ufd = attr->info.bpf_fd; 4000 struct fd f; 4001 int err; 4002 4003 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4004 return -EINVAL; 4005 4006 f = fdget(ufd); 4007 if (!f.file) 4008 return -EBADFD; 4009 4010 if (f.file->f_op == &bpf_prog_fops) 4011 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr, 4012 uattr); 4013 else if (f.file->f_op == &bpf_map_fops) 4014 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr, 4015 uattr); 4016 else if (f.file->f_op == &btf_fops) 4017 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr); 4018 else if (f.file->f_op == &bpf_link_fops) 4019 err = bpf_link_get_info_by_fd(f.file, f.file->private_data, 4020 attr, uattr); 4021 else 4022 err = -EINVAL; 4023 4024 fdput(f); 4025 return err; 4026 } 4027 4028 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 4029 4030 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr) 4031 { 4032 if (CHECK_ATTR(BPF_BTF_LOAD)) 4033 return -EINVAL; 4034 4035 if (!bpf_capable()) 4036 return -EPERM; 4037 4038 return btf_new_fd(attr, uattr); 4039 } 4040 4041 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4042 4043 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4044 { 4045 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4046 return -EINVAL; 4047 4048 if (!capable(CAP_SYS_ADMIN)) 4049 return -EPERM; 4050 4051 return btf_get_fd_by_id(attr->btf_id); 4052 } 4053 4054 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 4055 union bpf_attr __user *uattr, 4056 u32 prog_id, u32 fd_type, 4057 const char *buf, u64 probe_offset, 4058 u64 probe_addr) 4059 { 4060 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 4061 u32 len = buf ? strlen(buf) : 0, input_len; 4062 int err = 0; 4063 4064 if (put_user(len, &uattr->task_fd_query.buf_len)) 4065 return -EFAULT; 4066 input_len = attr->task_fd_query.buf_len; 4067 if (input_len && ubuf) { 4068 if (!len) { 4069 /* nothing to copy, just make ubuf NULL terminated */ 4070 char zero = '\0'; 4071 4072 if (put_user(zero, ubuf)) 4073 return -EFAULT; 4074 } else if (input_len >= len + 1) { 4075 /* ubuf can hold the string with NULL terminator */ 4076 if (copy_to_user(ubuf, buf, len + 1)) 4077 return -EFAULT; 4078 } else { 4079 /* ubuf cannot hold the string with NULL terminator, 4080 * do a partial copy with NULL terminator. 4081 */ 4082 char zero = '\0'; 4083 4084 err = -ENOSPC; 4085 if (copy_to_user(ubuf, buf, input_len - 1)) 4086 return -EFAULT; 4087 if (put_user(zero, ubuf + input_len - 1)) 4088 return -EFAULT; 4089 } 4090 } 4091 4092 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 4093 put_user(fd_type, &uattr->task_fd_query.fd_type) || 4094 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 4095 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 4096 return -EFAULT; 4097 4098 return err; 4099 } 4100 4101 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 4102 4103 static int bpf_task_fd_query(const union bpf_attr *attr, 4104 union bpf_attr __user *uattr) 4105 { 4106 pid_t pid = attr->task_fd_query.pid; 4107 u32 fd = attr->task_fd_query.fd; 4108 const struct perf_event *event; 4109 struct task_struct *task; 4110 struct file *file; 4111 int err; 4112 4113 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 4114 return -EINVAL; 4115 4116 if (!capable(CAP_SYS_ADMIN)) 4117 return -EPERM; 4118 4119 if (attr->task_fd_query.flags != 0) 4120 return -EINVAL; 4121 4122 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 4123 if (!task) 4124 return -ENOENT; 4125 4126 err = 0; 4127 file = fget_task(task, fd); 4128 put_task_struct(task); 4129 if (!file) 4130 return -EBADF; 4131 4132 if (file->f_op == &bpf_link_fops) { 4133 struct bpf_link *link = file->private_data; 4134 4135 if (link->ops == &bpf_raw_tp_link_lops) { 4136 struct bpf_raw_tp_link *raw_tp = 4137 container_of(link, struct bpf_raw_tp_link, link); 4138 struct bpf_raw_event_map *btp = raw_tp->btp; 4139 4140 err = bpf_task_fd_query_copy(attr, uattr, 4141 raw_tp->link.prog->aux->id, 4142 BPF_FD_TYPE_RAW_TRACEPOINT, 4143 btp->tp->name, 0, 0); 4144 goto put_file; 4145 } 4146 goto out_not_supp; 4147 } 4148 4149 event = perf_get_event(file); 4150 if (!IS_ERR(event)) { 4151 u64 probe_offset, probe_addr; 4152 u32 prog_id, fd_type; 4153 const char *buf; 4154 4155 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 4156 &buf, &probe_offset, 4157 &probe_addr); 4158 if (!err) 4159 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 4160 fd_type, buf, 4161 probe_offset, 4162 probe_addr); 4163 goto put_file; 4164 } 4165 4166 out_not_supp: 4167 err = -ENOTSUPP; 4168 put_file: 4169 fput(file); 4170 return err; 4171 } 4172 4173 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 4174 4175 #define BPF_DO_BATCH(fn) \ 4176 do { \ 4177 if (!fn) { \ 4178 err = -ENOTSUPP; \ 4179 goto err_put; \ 4180 } \ 4181 err = fn(map, attr, uattr); \ 4182 } while (0) 4183 4184 static int bpf_map_do_batch(const union bpf_attr *attr, 4185 union bpf_attr __user *uattr, 4186 int cmd) 4187 { 4188 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 4189 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 4190 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 4191 struct bpf_map *map; 4192 int err, ufd; 4193 struct fd f; 4194 4195 if (CHECK_ATTR(BPF_MAP_BATCH)) 4196 return -EINVAL; 4197 4198 ufd = attr->batch.map_fd; 4199 f = fdget(ufd); 4200 map = __bpf_map_get(f); 4201 if (IS_ERR(map)) 4202 return PTR_ERR(map); 4203 if (has_write) 4204 bpf_map_write_active_inc(map); 4205 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 4206 err = -EPERM; 4207 goto err_put; 4208 } 4209 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 4210 err = -EPERM; 4211 goto err_put; 4212 } 4213 4214 if (cmd == BPF_MAP_LOOKUP_BATCH) 4215 BPF_DO_BATCH(map->ops->map_lookup_batch); 4216 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 4217 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 4218 else if (cmd == BPF_MAP_UPDATE_BATCH) 4219 BPF_DO_BATCH(map->ops->map_update_batch); 4220 else 4221 BPF_DO_BATCH(map->ops->map_delete_batch); 4222 err_put: 4223 if (has_write) 4224 bpf_map_write_active_dec(map); 4225 fdput(f); 4226 return err; 4227 } 4228 4229 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, 4230 struct bpf_prog *prog) 4231 { 4232 if (attr->link_create.attach_type != prog->expected_attach_type) 4233 return -EINVAL; 4234 4235 if (prog->expected_attach_type == BPF_TRACE_ITER) 4236 return bpf_iter_link_attach(attr, uattr, prog); 4237 else if (prog->type == BPF_PROG_TYPE_EXT) 4238 return bpf_tracing_prog_attach(prog, 4239 attr->link_create.target_fd, 4240 attr->link_create.target_btf_id); 4241 return -EINVAL; 4242 } 4243 4244 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len 4245 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 4246 { 4247 enum bpf_prog_type ptype; 4248 struct bpf_prog *prog; 4249 int ret; 4250 4251 if (CHECK_ATTR(BPF_LINK_CREATE)) 4252 return -EINVAL; 4253 4254 prog = bpf_prog_get(attr->link_create.prog_fd); 4255 if (IS_ERR(prog)) 4256 return PTR_ERR(prog); 4257 4258 ret = bpf_prog_attach_check_attach_type(prog, 4259 attr->link_create.attach_type); 4260 if (ret) 4261 goto out; 4262 4263 switch (prog->type) { 4264 case BPF_PROG_TYPE_EXT: 4265 ret = tracing_bpf_link_attach(attr, uattr, prog); 4266 goto out; 4267 case BPF_PROG_TYPE_PERF_EVENT: 4268 case BPF_PROG_TYPE_KPROBE: 4269 case BPF_PROG_TYPE_TRACEPOINT: 4270 if (attr->link_create.attach_type != BPF_PERF_EVENT) { 4271 ret = -EINVAL; 4272 goto out; 4273 } 4274 ptype = prog->type; 4275 break; 4276 default: 4277 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 4278 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) { 4279 ret = -EINVAL; 4280 goto out; 4281 } 4282 break; 4283 } 4284 4285 switch (ptype) { 4286 case BPF_PROG_TYPE_CGROUP_SKB: 4287 case BPF_PROG_TYPE_CGROUP_SOCK: 4288 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4289 case BPF_PROG_TYPE_SOCK_OPS: 4290 case BPF_PROG_TYPE_CGROUP_DEVICE: 4291 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4292 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4293 ret = cgroup_bpf_link_attach(attr, prog); 4294 break; 4295 case BPF_PROG_TYPE_TRACING: 4296 ret = tracing_bpf_link_attach(attr, uattr, prog); 4297 break; 4298 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4299 case BPF_PROG_TYPE_SK_LOOKUP: 4300 ret = netns_bpf_link_create(attr, prog); 4301 break; 4302 #ifdef CONFIG_NET 4303 case BPF_PROG_TYPE_XDP: 4304 ret = bpf_xdp_link_attach(attr, prog); 4305 break; 4306 #endif 4307 #ifdef CONFIG_PERF_EVENTS 4308 case BPF_PROG_TYPE_PERF_EVENT: 4309 case BPF_PROG_TYPE_TRACEPOINT: 4310 case BPF_PROG_TYPE_KPROBE: 4311 ret = bpf_perf_link_attach(attr, prog); 4312 break; 4313 #endif 4314 default: 4315 ret = -EINVAL; 4316 } 4317 4318 out: 4319 if (ret < 0) 4320 bpf_prog_put(prog); 4321 return ret; 4322 } 4323 4324 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 4325 4326 static int link_update(union bpf_attr *attr) 4327 { 4328 struct bpf_prog *old_prog = NULL, *new_prog; 4329 struct bpf_link *link; 4330 u32 flags; 4331 int ret; 4332 4333 if (CHECK_ATTR(BPF_LINK_UPDATE)) 4334 return -EINVAL; 4335 4336 flags = attr->link_update.flags; 4337 if (flags & ~BPF_F_REPLACE) 4338 return -EINVAL; 4339 4340 link = bpf_link_get_from_fd(attr->link_update.link_fd); 4341 if (IS_ERR(link)) 4342 return PTR_ERR(link); 4343 4344 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 4345 if (IS_ERR(new_prog)) { 4346 ret = PTR_ERR(new_prog); 4347 goto out_put_link; 4348 } 4349 4350 if (flags & BPF_F_REPLACE) { 4351 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 4352 if (IS_ERR(old_prog)) { 4353 ret = PTR_ERR(old_prog); 4354 old_prog = NULL; 4355 goto out_put_progs; 4356 } 4357 } else if (attr->link_update.old_prog_fd) { 4358 ret = -EINVAL; 4359 goto out_put_progs; 4360 } 4361 4362 if (link->ops->update_prog) 4363 ret = link->ops->update_prog(link, new_prog, old_prog); 4364 else 4365 ret = -EINVAL; 4366 4367 out_put_progs: 4368 if (old_prog) 4369 bpf_prog_put(old_prog); 4370 if (ret) 4371 bpf_prog_put(new_prog); 4372 out_put_link: 4373 bpf_link_put(link); 4374 return ret; 4375 } 4376 4377 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 4378 4379 static int link_detach(union bpf_attr *attr) 4380 { 4381 struct bpf_link *link; 4382 int ret; 4383 4384 if (CHECK_ATTR(BPF_LINK_DETACH)) 4385 return -EINVAL; 4386 4387 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 4388 if (IS_ERR(link)) 4389 return PTR_ERR(link); 4390 4391 if (link->ops->detach) 4392 ret = link->ops->detach(link); 4393 else 4394 ret = -EOPNOTSUPP; 4395 4396 bpf_link_put(link); 4397 return ret; 4398 } 4399 4400 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 4401 { 4402 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 4403 } 4404 4405 struct bpf_link *bpf_link_by_id(u32 id) 4406 { 4407 struct bpf_link *link; 4408 4409 if (!id) 4410 return ERR_PTR(-ENOENT); 4411 4412 spin_lock_bh(&link_idr_lock); 4413 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 4414 link = idr_find(&link_idr, id); 4415 if (link) { 4416 if (link->id) 4417 link = bpf_link_inc_not_zero(link); 4418 else 4419 link = ERR_PTR(-EAGAIN); 4420 } else { 4421 link = ERR_PTR(-ENOENT); 4422 } 4423 spin_unlock_bh(&link_idr_lock); 4424 return link; 4425 } 4426 4427 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 4428 4429 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 4430 { 4431 struct bpf_link *link; 4432 u32 id = attr->link_id; 4433 int fd; 4434 4435 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 4436 return -EINVAL; 4437 4438 if (!capable(CAP_SYS_ADMIN)) 4439 return -EPERM; 4440 4441 link = bpf_link_by_id(id); 4442 if (IS_ERR(link)) 4443 return PTR_ERR(link); 4444 4445 fd = bpf_link_new_fd(link); 4446 if (fd < 0) 4447 bpf_link_put(link); 4448 4449 return fd; 4450 } 4451 4452 DEFINE_MUTEX(bpf_stats_enabled_mutex); 4453 4454 static int bpf_stats_release(struct inode *inode, struct file *file) 4455 { 4456 mutex_lock(&bpf_stats_enabled_mutex); 4457 static_key_slow_dec(&bpf_stats_enabled_key.key); 4458 mutex_unlock(&bpf_stats_enabled_mutex); 4459 return 0; 4460 } 4461 4462 static const struct file_operations bpf_stats_fops = { 4463 .release = bpf_stats_release, 4464 }; 4465 4466 static int bpf_enable_runtime_stats(void) 4467 { 4468 int fd; 4469 4470 mutex_lock(&bpf_stats_enabled_mutex); 4471 4472 /* Set a very high limit to avoid overflow */ 4473 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 4474 mutex_unlock(&bpf_stats_enabled_mutex); 4475 return -EBUSY; 4476 } 4477 4478 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 4479 if (fd >= 0) 4480 static_key_slow_inc(&bpf_stats_enabled_key.key); 4481 4482 mutex_unlock(&bpf_stats_enabled_mutex); 4483 return fd; 4484 } 4485 4486 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 4487 4488 static int bpf_enable_stats(union bpf_attr *attr) 4489 { 4490 4491 if (CHECK_ATTR(BPF_ENABLE_STATS)) 4492 return -EINVAL; 4493 4494 if (!capable(CAP_SYS_ADMIN)) 4495 return -EPERM; 4496 4497 switch (attr->enable_stats.type) { 4498 case BPF_STATS_RUN_TIME: 4499 return bpf_enable_runtime_stats(); 4500 default: 4501 break; 4502 } 4503 return -EINVAL; 4504 } 4505 4506 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 4507 4508 static int bpf_iter_create(union bpf_attr *attr) 4509 { 4510 struct bpf_link *link; 4511 int err; 4512 4513 if (CHECK_ATTR(BPF_ITER_CREATE)) 4514 return -EINVAL; 4515 4516 if (attr->iter_create.flags) 4517 return -EINVAL; 4518 4519 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 4520 if (IS_ERR(link)) 4521 return PTR_ERR(link); 4522 4523 err = bpf_iter_new_fd(link); 4524 bpf_link_put(link); 4525 4526 return err; 4527 } 4528 4529 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 4530 4531 static int bpf_prog_bind_map(union bpf_attr *attr) 4532 { 4533 struct bpf_prog *prog; 4534 struct bpf_map *map; 4535 struct bpf_map **used_maps_old, **used_maps_new; 4536 int i, ret = 0; 4537 4538 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 4539 return -EINVAL; 4540 4541 if (attr->prog_bind_map.flags) 4542 return -EINVAL; 4543 4544 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 4545 if (IS_ERR(prog)) 4546 return PTR_ERR(prog); 4547 4548 map = bpf_map_get(attr->prog_bind_map.map_fd); 4549 if (IS_ERR(map)) { 4550 ret = PTR_ERR(map); 4551 goto out_prog_put; 4552 } 4553 4554 mutex_lock(&prog->aux->used_maps_mutex); 4555 4556 used_maps_old = prog->aux->used_maps; 4557 4558 for (i = 0; i < prog->aux->used_map_cnt; i++) 4559 if (used_maps_old[i] == map) { 4560 bpf_map_put(map); 4561 goto out_unlock; 4562 } 4563 4564 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 4565 sizeof(used_maps_new[0]), 4566 GFP_KERNEL); 4567 if (!used_maps_new) { 4568 ret = -ENOMEM; 4569 goto out_unlock; 4570 } 4571 4572 memcpy(used_maps_new, used_maps_old, 4573 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 4574 used_maps_new[prog->aux->used_map_cnt] = map; 4575 4576 prog->aux->used_map_cnt++; 4577 prog->aux->used_maps = used_maps_new; 4578 4579 kfree(used_maps_old); 4580 4581 out_unlock: 4582 mutex_unlock(&prog->aux->used_maps_mutex); 4583 4584 if (ret) 4585 bpf_map_put(map); 4586 out_prog_put: 4587 bpf_prog_put(prog); 4588 return ret; 4589 } 4590 4591 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) 4592 { 4593 union bpf_attr attr; 4594 int err; 4595 4596 if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) 4597 return -EPERM; 4598 4599 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 4600 if (err) 4601 return err; 4602 size = min_t(u32, size, sizeof(attr)); 4603 4604 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 4605 memset(&attr, 0, sizeof(attr)); 4606 if (copy_from_bpfptr(&attr, uattr, size) != 0) 4607 return -EFAULT; 4608 4609 err = security_bpf(cmd, &attr, size); 4610 if (err < 0) 4611 return err; 4612 4613 switch (cmd) { 4614 case BPF_MAP_CREATE: 4615 err = map_create(&attr); 4616 break; 4617 case BPF_MAP_LOOKUP_ELEM: 4618 err = map_lookup_elem(&attr); 4619 break; 4620 case BPF_MAP_UPDATE_ELEM: 4621 err = map_update_elem(&attr, uattr); 4622 break; 4623 case BPF_MAP_DELETE_ELEM: 4624 err = map_delete_elem(&attr); 4625 break; 4626 case BPF_MAP_GET_NEXT_KEY: 4627 err = map_get_next_key(&attr); 4628 break; 4629 case BPF_MAP_FREEZE: 4630 err = map_freeze(&attr); 4631 break; 4632 case BPF_PROG_LOAD: 4633 err = bpf_prog_load(&attr, uattr); 4634 break; 4635 case BPF_OBJ_PIN: 4636 err = bpf_obj_pin(&attr); 4637 break; 4638 case BPF_OBJ_GET: 4639 err = bpf_obj_get(&attr); 4640 break; 4641 case BPF_PROG_ATTACH: 4642 err = bpf_prog_attach(&attr); 4643 break; 4644 case BPF_PROG_DETACH: 4645 err = bpf_prog_detach(&attr); 4646 break; 4647 case BPF_PROG_QUERY: 4648 err = bpf_prog_query(&attr, uattr.user); 4649 break; 4650 case BPF_PROG_TEST_RUN: 4651 err = bpf_prog_test_run(&attr, uattr.user); 4652 break; 4653 case BPF_PROG_GET_NEXT_ID: 4654 err = bpf_obj_get_next_id(&attr, uattr.user, 4655 &prog_idr, &prog_idr_lock); 4656 break; 4657 case BPF_MAP_GET_NEXT_ID: 4658 err = bpf_obj_get_next_id(&attr, uattr.user, 4659 &map_idr, &map_idr_lock); 4660 break; 4661 case BPF_BTF_GET_NEXT_ID: 4662 err = bpf_obj_get_next_id(&attr, uattr.user, 4663 &btf_idr, &btf_idr_lock); 4664 break; 4665 case BPF_PROG_GET_FD_BY_ID: 4666 err = bpf_prog_get_fd_by_id(&attr); 4667 break; 4668 case BPF_MAP_GET_FD_BY_ID: 4669 err = bpf_map_get_fd_by_id(&attr); 4670 break; 4671 case BPF_OBJ_GET_INFO_BY_FD: 4672 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 4673 break; 4674 case BPF_RAW_TRACEPOINT_OPEN: 4675 err = bpf_raw_tracepoint_open(&attr); 4676 break; 4677 case BPF_BTF_LOAD: 4678 err = bpf_btf_load(&attr, uattr); 4679 break; 4680 case BPF_BTF_GET_FD_BY_ID: 4681 err = bpf_btf_get_fd_by_id(&attr); 4682 break; 4683 case BPF_TASK_FD_QUERY: 4684 err = bpf_task_fd_query(&attr, uattr.user); 4685 break; 4686 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 4687 err = map_lookup_and_delete_elem(&attr); 4688 break; 4689 case BPF_MAP_LOOKUP_BATCH: 4690 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 4691 break; 4692 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 4693 err = bpf_map_do_batch(&attr, uattr.user, 4694 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 4695 break; 4696 case BPF_MAP_UPDATE_BATCH: 4697 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 4698 break; 4699 case BPF_MAP_DELETE_BATCH: 4700 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 4701 break; 4702 case BPF_LINK_CREATE: 4703 err = link_create(&attr, uattr); 4704 break; 4705 case BPF_LINK_UPDATE: 4706 err = link_update(&attr); 4707 break; 4708 case BPF_LINK_GET_FD_BY_ID: 4709 err = bpf_link_get_fd_by_id(&attr); 4710 break; 4711 case BPF_LINK_GET_NEXT_ID: 4712 err = bpf_obj_get_next_id(&attr, uattr.user, 4713 &link_idr, &link_idr_lock); 4714 break; 4715 case BPF_ENABLE_STATS: 4716 err = bpf_enable_stats(&attr); 4717 break; 4718 case BPF_ITER_CREATE: 4719 err = bpf_iter_create(&attr); 4720 break; 4721 case BPF_LINK_DETACH: 4722 err = link_detach(&attr); 4723 break; 4724 case BPF_PROG_BIND_MAP: 4725 err = bpf_prog_bind_map(&attr); 4726 break; 4727 default: 4728 err = -EINVAL; 4729 break; 4730 } 4731 4732 return err; 4733 } 4734 4735 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 4736 { 4737 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 4738 } 4739 4740 static bool syscall_prog_is_valid_access(int off, int size, 4741 enum bpf_access_type type, 4742 const struct bpf_prog *prog, 4743 struct bpf_insn_access_aux *info) 4744 { 4745 if (off < 0 || off >= U16_MAX) 4746 return false; 4747 if (off % size != 0) 4748 return false; 4749 return true; 4750 } 4751 4752 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size) 4753 { 4754 switch (cmd) { 4755 case BPF_MAP_CREATE: 4756 case BPF_MAP_UPDATE_ELEM: 4757 case BPF_MAP_FREEZE: 4758 case BPF_PROG_LOAD: 4759 case BPF_BTF_LOAD: 4760 break; 4761 /* case BPF_PROG_TEST_RUN: 4762 * is not part of this list to prevent recursive test_run 4763 */ 4764 default: 4765 return -EINVAL; 4766 } 4767 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 4768 } 4769 4770 static const struct bpf_func_proto bpf_sys_bpf_proto = { 4771 .func = bpf_sys_bpf, 4772 .gpl_only = false, 4773 .ret_type = RET_INTEGER, 4774 .arg1_type = ARG_ANYTHING, 4775 .arg2_type = ARG_PTR_TO_MEM, 4776 .arg3_type = ARG_CONST_SIZE, 4777 }; 4778 4779 const struct bpf_func_proto * __weak 4780 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4781 { 4782 return bpf_base_func_proto(func_id); 4783 } 4784 4785 BPF_CALL_1(bpf_sys_close, u32, fd) 4786 { 4787 /* When bpf program calls this helper there should not be 4788 * an fdget() without matching completed fdput(). 4789 * This helper is allowed in the following callchain only: 4790 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 4791 */ 4792 return close_fd(fd); 4793 } 4794 4795 static const struct bpf_func_proto bpf_sys_close_proto = { 4796 .func = bpf_sys_close, 4797 .gpl_only = false, 4798 .ret_type = RET_INTEGER, 4799 .arg1_type = ARG_ANYTHING, 4800 }; 4801 4802 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 4803 { 4804 if (flags) 4805 return -EINVAL; 4806 4807 if (name_sz <= 1 || name[name_sz - 1]) 4808 return -EINVAL; 4809 4810 if (!bpf_dump_raw_ok(current_cred())) 4811 return -EPERM; 4812 4813 *res = kallsyms_lookup_name(name); 4814 return *res ? 0 : -ENOENT; 4815 } 4816 4817 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 4818 .func = bpf_kallsyms_lookup_name, 4819 .gpl_only = false, 4820 .ret_type = RET_INTEGER, 4821 .arg1_type = ARG_PTR_TO_MEM, 4822 .arg2_type = ARG_CONST_SIZE, 4823 .arg3_type = ARG_ANYTHING, 4824 .arg4_type = ARG_PTR_TO_LONG, 4825 }; 4826 4827 static const struct bpf_func_proto * 4828 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4829 { 4830 switch (func_id) { 4831 case BPF_FUNC_sys_bpf: 4832 return &bpf_sys_bpf_proto; 4833 case BPF_FUNC_btf_find_by_name_kind: 4834 return &bpf_btf_find_by_name_kind_proto; 4835 case BPF_FUNC_sys_close: 4836 return &bpf_sys_close_proto; 4837 case BPF_FUNC_kallsyms_lookup_name: 4838 return &bpf_kallsyms_lookup_name_proto; 4839 default: 4840 return tracing_prog_func_proto(func_id, prog); 4841 } 4842 } 4843 4844 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 4845 .get_func_proto = syscall_prog_func_proto, 4846 .is_valid_access = syscall_prog_is_valid_access, 4847 }; 4848 4849 const struct bpf_prog_ops bpf_syscall_prog_ops = { 4850 .test_run = bpf_prog_test_run_syscall, 4851 }; 4852