1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf-cgroup.h> 6 #include <linux/bpf_trace.h> 7 #include <linux/bpf_lirc.h> 8 #include <linux/bpf_verifier.h> 9 #include <linux/btf.h> 10 #include <linux/syscalls.h> 11 #include <linux/slab.h> 12 #include <linux/sched/signal.h> 13 #include <linux/vmalloc.h> 14 #include <linux/mmzone.h> 15 #include <linux/anon_inodes.h> 16 #include <linux/fdtable.h> 17 #include <linux/file.h> 18 #include <linux/fs.h> 19 #include <linux/license.h> 20 #include <linux/filter.h> 21 #include <linux/kernel.h> 22 #include <linux/idr.h> 23 #include <linux/cred.h> 24 #include <linux/timekeeping.h> 25 #include <linux/ctype.h> 26 #include <linux/nospec.h> 27 #include <linux/audit.h> 28 #include <uapi/linux/btf.h> 29 #include <linux/pgtable.h> 30 #include <linux/bpf_lsm.h> 31 #include <linux/poll.h> 32 #include <linux/bpf-netns.h> 33 #include <linux/rcupdate_trace.h> 34 #include <linux/memcontrol.h> 35 36 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 37 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 38 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 39 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 40 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 41 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 42 IS_FD_HASH(map)) 43 44 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 45 46 DEFINE_PER_CPU(int, bpf_prog_active); 47 static DEFINE_IDR(prog_idr); 48 static DEFINE_SPINLOCK(prog_idr_lock); 49 static DEFINE_IDR(map_idr); 50 static DEFINE_SPINLOCK(map_idr_lock); 51 static DEFINE_IDR(link_idr); 52 static DEFINE_SPINLOCK(link_idr_lock); 53 54 int sysctl_unprivileged_bpf_disabled __read_mostly = 55 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 56 57 static const struct bpf_map_ops * const bpf_map_types[] = { 58 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 59 #define BPF_MAP_TYPE(_id, _ops) \ 60 [_id] = &_ops, 61 #define BPF_LINK_TYPE(_id, _name) 62 #include <linux/bpf_types.h> 63 #undef BPF_PROG_TYPE 64 #undef BPF_MAP_TYPE 65 #undef BPF_LINK_TYPE 66 }; 67 68 /* 69 * If we're handed a bigger struct than we know of, ensure all the unknown bits 70 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 71 * we don't know about yet. 72 * 73 * There is a ToCToU between this function call and the following 74 * copy_from_user() call. However, this is not a concern since this function is 75 * meant to be a future-proofing of bits. 76 */ 77 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 78 size_t expected_size, 79 size_t actual_size) 80 { 81 int res; 82 83 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 84 return -E2BIG; 85 86 if (actual_size <= expected_size) 87 return 0; 88 89 if (uaddr.is_kernel) 90 res = memchr_inv(uaddr.kernel + expected_size, 0, 91 actual_size - expected_size) == NULL; 92 else 93 res = check_zeroed_user(uaddr.user + expected_size, 94 actual_size - expected_size); 95 if (res < 0) 96 return res; 97 return res ? 0 : -E2BIG; 98 } 99 100 const struct bpf_map_ops bpf_map_offload_ops = { 101 .map_meta_equal = bpf_map_meta_equal, 102 .map_alloc = bpf_map_offload_map_alloc, 103 .map_free = bpf_map_offload_map_free, 104 .map_check_btf = map_check_no_btf, 105 }; 106 107 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 108 { 109 const struct bpf_map_ops *ops; 110 u32 type = attr->map_type; 111 struct bpf_map *map; 112 int err; 113 114 if (type >= ARRAY_SIZE(bpf_map_types)) 115 return ERR_PTR(-EINVAL); 116 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 117 ops = bpf_map_types[type]; 118 if (!ops) 119 return ERR_PTR(-EINVAL); 120 121 if (ops->map_alloc_check) { 122 err = ops->map_alloc_check(attr); 123 if (err) 124 return ERR_PTR(err); 125 } 126 if (attr->map_ifindex) 127 ops = &bpf_map_offload_ops; 128 map = ops->map_alloc(attr); 129 if (IS_ERR(map)) 130 return map; 131 map->ops = ops; 132 map->map_type = type; 133 return map; 134 } 135 136 static void bpf_map_write_active_inc(struct bpf_map *map) 137 { 138 atomic64_inc(&map->writecnt); 139 } 140 141 static void bpf_map_write_active_dec(struct bpf_map *map) 142 { 143 atomic64_dec(&map->writecnt); 144 } 145 146 bool bpf_map_write_active(const struct bpf_map *map) 147 { 148 return atomic64_read(&map->writecnt) != 0; 149 } 150 151 static u32 bpf_map_value_size(const struct bpf_map *map) 152 { 153 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 154 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 155 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 156 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 157 return round_up(map->value_size, 8) * num_possible_cpus(); 158 else if (IS_FD_MAP(map)) 159 return sizeof(u32); 160 else 161 return map->value_size; 162 } 163 164 static void maybe_wait_bpf_programs(struct bpf_map *map) 165 { 166 /* Wait for any running BPF programs to complete so that 167 * userspace, when we return to it, knows that all programs 168 * that could be running use the new map value. 169 */ 170 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 171 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 172 synchronize_rcu(); 173 } 174 175 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 176 void *value, __u64 flags) 177 { 178 int err; 179 180 /* Need to create a kthread, thus must support schedule */ 181 if (bpf_map_is_dev_bound(map)) { 182 return bpf_map_offload_update_elem(map, key, value, flags); 183 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 184 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 185 return map->ops->map_update_elem(map, key, value, flags); 186 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 187 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 188 return sock_map_update_elem_sys(map, key, value, flags); 189 } else if (IS_FD_PROG_ARRAY(map)) { 190 return bpf_fd_array_map_update_elem(map, f.file, key, value, 191 flags); 192 } 193 194 bpf_disable_instrumentation(); 195 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 196 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 197 err = bpf_percpu_hash_update(map, key, value, flags); 198 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 199 err = bpf_percpu_array_update(map, key, value, flags); 200 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 201 err = bpf_percpu_cgroup_storage_update(map, key, value, 202 flags); 203 } else if (IS_FD_ARRAY(map)) { 204 rcu_read_lock(); 205 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 206 flags); 207 rcu_read_unlock(); 208 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 209 rcu_read_lock(); 210 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 211 flags); 212 rcu_read_unlock(); 213 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 214 /* rcu_read_lock() is not needed */ 215 err = bpf_fd_reuseport_array_update_elem(map, key, value, 216 flags); 217 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 218 map->map_type == BPF_MAP_TYPE_STACK || 219 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 220 err = map->ops->map_push_elem(map, value, flags); 221 } else { 222 rcu_read_lock(); 223 err = map->ops->map_update_elem(map, key, value, flags); 224 rcu_read_unlock(); 225 } 226 bpf_enable_instrumentation(); 227 maybe_wait_bpf_programs(map); 228 229 return err; 230 } 231 232 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 233 __u64 flags) 234 { 235 void *ptr; 236 int err; 237 238 if (bpf_map_is_dev_bound(map)) 239 return bpf_map_offload_lookup_elem(map, key, value); 240 241 bpf_disable_instrumentation(); 242 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 243 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 244 err = bpf_percpu_hash_copy(map, key, value); 245 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 246 err = bpf_percpu_array_copy(map, key, value); 247 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 248 err = bpf_percpu_cgroup_storage_copy(map, key, value); 249 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 250 err = bpf_stackmap_copy(map, key, value); 251 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 252 err = bpf_fd_array_map_lookup_elem(map, key, value); 253 } else if (IS_FD_HASH(map)) { 254 err = bpf_fd_htab_map_lookup_elem(map, key, value); 255 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 256 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 257 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 258 map->map_type == BPF_MAP_TYPE_STACK || 259 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 260 err = map->ops->map_peek_elem(map, value); 261 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 262 /* struct_ops map requires directly updating "value" */ 263 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 264 } else { 265 rcu_read_lock(); 266 if (map->ops->map_lookup_elem_sys_only) 267 ptr = map->ops->map_lookup_elem_sys_only(map, key); 268 else 269 ptr = map->ops->map_lookup_elem(map, key); 270 if (IS_ERR(ptr)) { 271 err = PTR_ERR(ptr); 272 } else if (!ptr) { 273 err = -ENOENT; 274 } else { 275 err = 0; 276 if (flags & BPF_F_LOCK) 277 /* lock 'ptr' and copy everything but lock */ 278 copy_map_value_locked(map, value, ptr, true); 279 else 280 copy_map_value(map, value, ptr); 281 /* mask lock and timer, since value wasn't zero inited */ 282 check_and_init_map_value(map, value); 283 } 284 rcu_read_unlock(); 285 } 286 287 bpf_enable_instrumentation(); 288 maybe_wait_bpf_programs(map); 289 290 return err; 291 } 292 293 /* Please, do not use this function outside from the map creation path 294 * (e.g. in map update path) without taking care of setting the active 295 * memory cgroup (see at bpf_map_kmalloc_node() for example). 296 */ 297 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 298 { 299 /* We really just want to fail instead of triggering OOM killer 300 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 301 * which is used for lower order allocation requests. 302 * 303 * It has been observed that higher order allocation requests done by 304 * vmalloc with __GFP_NORETRY being set might fail due to not trying 305 * to reclaim memory from the page cache, thus we set 306 * __GFP_RETRY_MAYFAIL to avoid such situations. 307 */ 308 309 const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT; 310 unsigned int flags = 0; 311 unsigned long align = 1; 312 void *area; 313 314 if (size >= SIZE_MAX) 315 return NULL; 316 317 /* kmalloc()'ed memory can't be mmap()'ed */ 318 if (mmapable) { 319 BUG_ON(!PAGE_ALIGNED(size)); 320 align = SHMLBA; 321 flags = VM_USERMAP; 322 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 323 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 324 numa_node); 325 if (area != NULL) 326 return area; 327 } 328 329 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 330 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 331 flags, numa_node, __builtin_return_address(0)); 332 } 333 334 void *bpf_map_area_alloc(u64 size, int numa_node) 335 { 336 return __bpf_map_area_alloc(size, numa_node, false); 337 } 338 339 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 340 { 341 return __bpf_map_area_alloc(size, numa_node, true); 342 } 343 344 void bpf_map_area_free(void *area) 345 { 346 kvfree(area); 347 } 348 349 static u32 bpf_map_flags_retain_permanent(u32 flags) 350 { 351 /* Some map creation flags are not tied to the map object but 352 * rather to the map fd instead, so they have no meaning upon 353 * map object inspection since multiple file descriptors with 354 * different (access) properties can exist here. Thus, given 355 * this has zero meaning for the map itself, lets clear these 356 * from here. 357 */ 358 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 359 } 360 361 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 362 { 363 map->map_type = attr->map_type; 364 map->key_size = attr->key_size; 365 map->value_size = attr->value_size; 366 map->max_entries = attr->max_entries; 367 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 368 map->numa_node = bpf_map_attr_numa_node(attr); 369 map->map_extra = attr->map_extra; 370 } 371 372 static int bpf_map_alloc_id(struct bpf_map *map) 373 { 374 int id; 375 376 idr_preload(GFP_KERNEL); 377 spin_lock_bh(&map_idr_lock); 378 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 379 if (id > 0) 380 map->id = id; 381 spin_unlock_bh(&map_idr_lock); 382 idr_preload_end(); 383 384 if (WARN_ON_ONCE(!id)) 385 return -ENOSPC; 386 387 return id > 0 ? 0 : id; 388 } 389 390 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 391 { 392 unsigned long flags; 393 394 /* Offloaded maps are removed from the IDR store when their device 395 * disappears - even if someone holds an fd to them they are unusable, 396 * the memory is gone, all ops will fail; they are simply waiting for 397 * refcnt to drop to be freed. 398 */ 399 if (!map->id) 400 return; 401 402 if (do_idr_lock) 403 spin_lock_irqsave(&map_idr_lock, flags); 404 else 405 __acquire(&map_idr_lock); 406 407 idr_remove(&map_idr, map->id); 408 map->id = 0; 409 410 if (do_idr_lock) 411 spin_unlock_irqrestore(&map_idr_lock, flags); 412 else 413 __release(&map_idr_lock); 414 } 415 416 #ifdef CONFIG_MEMCG_KMEM 417 static void bpf_map_save_memcg(struct bpf_map *map) 418 { 419 map->memcg = get_mem_cgroup_from_mm(current->mm); 420 } 421 422 static void bpf_map_release_memcg(struct bpf_map *map) 423 { 424 mem_cgroup_put(map->memcg); 425 } 426 427 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 428 int node) 429 { 430 struct mem_cgroup *old_memcg; 431 void *ptr; 432 433 old_memcg = set_active_memcg(map->memcg); 434 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 435 set_active_memcg(old_memcg); 436 437 return ptr; 438 } 439 440 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 441 { 442 struct mem_cgroup *old_memcg; 443 void *ptr; 444 445 old_memcg = set_active_memcg(map->memcg); 446 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 447 set_active_memcg(old_memcg); 448 449 return ptr; 450 } 451 452 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 453 size_t align, gfp_t flags) 454 { 455 struct mem_cgroup *old_memcg; 456 void __percpu *ptr; 457 458 old_memcg = set_active_memcg(map->memcg); 459 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 460 set_active_memcg(old_memcg); 461 462 return ptr; 463 } 464 465 #else 466 static void bpf_map_save_memcg(struct bpf_map *map) 467 { 468 } 469 470 static void bpf_map_release_memcg(struct bpf_map *map) 471 { 472 } 473 #endif 474 475 /* called from workqueue */ 476 static void bpf_map_free_deferred(struct work_struct *work) 477 { 478 struct bpf_map *map = container_of(work, struct bpf_map, work); 479 480 security_bpf_map_free(map); 481 bpf_map_release_memcg(map); 482 /* implementation dependent freeing */ 483 map->ops->map_free(map); 484 } 485 486 static void bpf_map_put_uref(struct bpf_map *map) 487 { 488 if (atomic64_dec_and_test(&map->usercnt)) { 489 if (map->ops->map_release_uref) 490 map->ops->map_release_uref(map); 491 } 492 } 493 494 /* decrement map refcnt and schedule it for freeing via workqueue 495 * (unrelying map implementation ops->map_free() might sleep) 496 */ 497 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 498 { 499 if (atomic64_dec_and_test(&map->refcnt)) { 500 /* bpf_map_free_id() must be called first */ 501 bpf_map_free_id(map, do_idr_lock); 502 btf_put(map->btf); 503 INIT_WORK(&map->work, bpf_map_free_deferred); 504 schedule_work(&map->work); 505 } 506 } 507 508 void bpf_map_put(struct bpf_map *map) 509 { 510 __bpf_map_put(map, true); 511 } 512 EXPORT_SYMBOL_GPL(bpf_map_put); 513 514 void bpf_map_put_with_uref(struct bpf_map *map) 515 { 516 bpf_map_put_uref(map); 517 bpf_map_put(map); 518 } 519 520 static int bpf_map_release(struct inode *inode, struct file *filp) 521 { 522 struct bpf_map *map = filp->private_data; 523 524 if (map->ops->map_release) 525 map->ops->map_release(map, filp); 526 527 bpf_map_put_with_uref(map); 528 return 0; 529 } 530 531 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 532 { 533 fmode_t mode = f.file->f_mode; 534 535 /* Our file permissions may have been overridden by global 536 * map permissions facing syscall side. 537 */ 538 if (READ_ONCE(map->frozen)) 539 mode &= ~FMODE_CAN_WRITE; 540 return mode; 541 } 542 543 #ifdef CONFIG_PROC_FS 544 /* Provides an approximation of the map's memory footprint. 545 * Used only to provide a backward compatibility and display 546 * a reasonable "memlock" info. 547 */ 548 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map) 549 { 550 unsigned long size; 551 552 size = round_up(map->key_size + bpf_map_value_size(map), 8); 553 554 return round_up(map->max_entries * size, PAGE_SIZE); 555 } 556 557 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 558 { 559 struct bpf_map *map = filp->private_data; 560 u32 type = 0, jited = 0; 561 562 if (map_type_contains_progs(map)) { 563 spin_lock(&map->owner.lock); 564 type = map->owner.type; 565 jited = map->owner.jited; 566 spin_unlock(&map->owner.lock); 567 } 568 569 seq_printf(m, 570 "map_type:\t%u\n" 571 "key_size:\t%u\n" 572 "value_size:\t%u\n" 573 "max_entries:\t%u\n" 574 "map_flags:\t%#x\n" 575 "map_extra:\t%#llx\n" 576 "memlock:\t%lu\n" 577 "map_id:\t%u\n" 578 "frozen:\t%u\n", 579 map->map_type, 580 map->key_size, 581 map->value_size, 582 map->max_entries, 583 map->map_flags, 584 (unsigned long long)map->map_extra, 585 bpf_map_memory_footprint(map), 586 map->id, 587 READ_ONCE(map->frozen)); 588 if (type) { 589 seq_printf(m, "owner_prog_type:\t%u\n", type); 590 seq_printf(m, "owner_jited:\t%u\n", jited); 591 } 592 } 593 #endif 594 595 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 596 loff_t *ppos) 597 { 598 /* We need this handler such that alloc_file() enables 599 * f_mode with FMODE_CAN_READ. 600 */ 601 return -EINVAL; 602 } 603 604 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 605 size_t siz, loff_t *ppos) 606 { 607 /* We need this handler such that alloc_file() enables 608 * f_mode with FMODE_CAN_WRITE. 609 */ 610 return -EINVAL; 611 } 612 613 /* called for any extra memory-mapped regions (except initial) */ 614 static void bpf_map_mmap_open(struct vm_area_struct *vma) 615 { 616 struct bpf_map *map = vma->vm_file->private_data; 617 618 if (vma->vm_flags & VM_MAYWRITE) 619 bpf_map_write_active_inc(map); 620 } 621 622 /* called for all unmapped memory region (including initial) */ 623 static void bpf_map_mmap_close(struct vm_area_struct *vma) 624 { 625 struct bpf_map *map = vma->vm_file->private_data; 626 627 if (vma->vm_flags & VM_MAYWRITE) 628 bpf_map_write_active_dec(map); 629 } 630 631 static const struct vm_operations_struct bpf_map_default_vmops = { 632 .open = bpf_map_mmap_open, 633 .close = bpf_map_mmap_close, 634 }; 635 636 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 637 { 638 struct bpf_map *map = filp->private_data; 639 int err; 640 641 if (!map->ops->map_mmap || map_value_has_spin_lock(map) || 642 map_value_has_timer(map)) 643 return -ENOTSUPP; 644 645 if (!(vma->vm_flags & VM_SHARED)) 646 return -EINVAL; 647 648 mutex_lock(&map->freeze_mutex); 649 650 if (vma->vm_flags & VM_WRITE) { 651 if (map->frozen) { 652 err = -EPERM; 653 goto out; 654 } 655 /* map is meant to be read-only, so do not allow mapping as 656 * writable, because it's possible to leak a writable page 657 * reference and allows user-space to still modify it after 658 * freezing, while verifier will assume contents do not change 659 */ 660 if (map->map_flags & BPF_F_RDONLY_PROG) { 661 err = -EACCES; 662 goto out; 663 } 664 } 665 666 /* set default open/close callbacks */ 667 vma->vm_ops = &bpf_map_default_vmops; 668 vma->vm_private_data = map; 669 vma->vm_flags &= ~VM_MAYEXEC; 670 if (!(vma->vm_flags & VM_WRITE)) 671 /* disallow re-mapping with PROT_WRITE */ 672 vma->vm_flags &= ~VM_MAYWRITE; 673 674 err = map->ops->map_mmap(map, vma); 675 if (err) 676 goto out; 677 678 if (vma->vm_flags & VM_MAYWRITE) 679 bpf_map_write_active_inc(map); 680 out: 681 mutex_unlock(&map->freeze_mutex); 682 return err; 683 } 684 685 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 686 { 687 struct bpf_map *map = filp->private_data; 688 689 if (map->ops->map_poll) 690 return map->ops->map_poll(map, filp, pts); 691 692 return EPOLLERR; 693 } 694 695 const struct file_operations bpf_map_fops = { 696 #ifdef CONFIG_PROC_FS 697 .show_fdinfo = bpf_map_show_fdinfo, 698 #endif 699 .release = bpf_map_release, 700 .read = bpf_dummy_read, 701 .write = bpf_dummy_write, 702 .mmap = bpf_map_mmap, 703 .poll = bpf_map_poll, 704 }; 705 706 int bpf_map_new_fd(struct bpf_map *map, int flags) 707 { 708 int ret; 709 710 ret = security_bpf_map(map, OPEN_FMODE(flags)); 711 if (ret < 0) 712 return ret; 713 714 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 715 flags | O_CLOEXEC); 716 } 717 718 int bpf_get_file_flag(int flags) 719 { 720 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 721 return -EINVAL; 722 if (flags & BPF_F_RDONLY) 723 return O_RDONLY; 724 if (flags & BPF_F_WRONLY) 725 return O_WRONLY; 726 return O_RDWR; 727 } 728 729 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 730 #define CHECK_ATTR(CMD) \ 731 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 732 sizeof(attr->CMD##_LAST_FIELD), 0, \ 733 sizeof(*attr) - \ 734 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 735 sizeof(attr->CMD##_LAST_FIELD)) != NULL 736 737 /* dst and src must have at least "size" number of bytes. 738 * Return strlen on success and < 0 on error. 739 */ 740 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 741 { 742 const char *end = src + size; 743 const char *orig_src = src; 744 745 memset(dst, 0, size); 746 /* Copy all isalnum(), '_' and '.' chars. */ 747 while (src < end && *src) { 748 if (!isalnum(*src) && 749 *src != '_' && *src != '.') 750 return -EINVAL; 751 *dst++ = *src++; 752 } 753 754 /* No '\0' found in "size" number of bytes */ 755 if (src == end) 756 return -EINVAL; 757 758 return src - orig_src; 759 } 760 761 int map_check_no_btf(const struct bpf_map *map, 762 const struct btf *btf, 763 const struct btf_type *key_type, 764 const struct btf_type *value_type) 765 { 766 return -ENOTSUPP; 767 } 768 769 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 770 u32 btf_key_id, u32 btf_value_id) 771 { 772 const struct btf_type *key_type, *value_type; 773 u32 key_size, value_size; 774 int ret = 0; 775 776 /* Some maps allow key to be unspecified. */ 777 if (btf_key_id) { 778 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 779 if (!key_type || key_size != map->key_size) 780 return -EINVAL; 781 } else { 782 key_type = btf_type_by_id(btf, 0); 783 if (!map->ops->map_check_btf) 784 return -EINVAL; 785 } 786 787 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 788 if (!value_type || value_size != map->value_size) 789 return -EINVAL; 790 791 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 792 793 if (map_value_has_spin_lock(map)) { 794 if (map->map_flags & BPF_F_RDONLY_PROG) 795 return -EACCES; 796 if (map->map_type != BPF_MAP_TYPE_HASH && 797 map->map_type != BPF_MAP_TYPE_ARRAY && 798 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 799 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 800 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 801 map->map_type != BPF_MAP_TYPE_TASK_STORAGE) 802 return -ENOTSUPP; 803 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 804 map->value_size) { 805 WARN_ONCE(1, 806 "verifier bug spin_lock_off %d value_size %d\n", 807 map->spin_lock_off, map->value_size); 808 return -EFAULT; 809 } 810 } 811 812 map->timer_off = btf_find_timer(btf, value_type); 813 if (map_value_has_timer(map)) { 814 if (map->map_flags & BPF_F_RDONLY_PROG) 815 return -EACCES; 816 if (map->map_type != BPF_MAP_TYPE_HASH && 817 map->map_type != BPF_MAP_TYPE_LRU_HASH && 818 map->map_type != BPF_MAP_TYPE_ARRAY) 819 return -EOPNOTSUPP; 820 } 821 822 if (map->ops->map_check_btf) 823 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 824 825 return ret; 826 } 827 828 #define BPF_MAP_CREATE_LAST_FIELD map_extra 829 /* called via syscall */ 830 static int map_create(union bpf_attr *attr) 831 { 832 int numa_node = bpf_map_attr_numa_node(attr); 833 struct bpf_map *map; 834 int f_flags; 835 int err; 836 837 err = CHECK_ATTR(BPF_MAP_CREATE); 838 if (err) 839 return -EINVAL; 840 841 if (attr->btf_vmlinux_value_type_id) { 842 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 843 attr->btf_key_type_id || attr->btf_value_type_id) 844 return -EINVAL; 845 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 846 return -EINVAL; 847 } 848 849 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 850 attr->map_extra != 0) 851 return -EINVAL; 852 853 f_flags = bpf_get_file_flag(attr->map_flags); 854 if (f_flags < 0) 855 return f_flags; 856 857 if (numa_node != NUMA_NO_NODE && 858 ((unsigned int)numa_node >= nr_node_ids || 859 !node_online(numa_node))) 860 return -EINVAL; 861 862 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 863 map = find_and_alloc_map(attr); 864 if (IS_ERR(map)) 865 return PTR_ERR(map); 866 867 err = bpf_obj_name_cpy(map->name, attr->map_name, 868 sizeof(attr->map_name)); 869 if (err < 0) 870 goto free_map; 871 872 atomic64_set(&map->refcnt, 1); 873 atomic64_set(&map->usercnt, 1); 874 mutex_init(&map->freeze_mutex); 875 spin_lock_init(&map->owner.lock); 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 core_relo_rec_size 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 BPF_F_XDP_HAS_FRAGS)) 2221 return -EINVAL; 2222 2223 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2224 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2225 !bpf_capable()) 2226 return -EPERM; 2227 2228 /* copy eBPF program license from user space */ 2229 if (strncpy_from_bpfptr(license, 2230 make_bpfptr(attr->license, uattr.is_kernel), 2231 sizeof(license) - 1) < 0) 2232 return -EFAULT; 2233 license[sizeof(license) - 1] = 0; 2234 2235 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2236 is_gpl = license_is_gpl_compatible(license); 2237 2238 if (attr->insn_cnt == 0 || 2239 attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2240 return -E2BIG; 2241 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2242 type != BPF_PROG_TYPE_CGROUP_SKB && 2243 !bpf_capable()) 2244 return -EPERM; 2245 2246 if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN)) 2247 return -EPERM; 2248 if (is_perfmon_prog_type(type) && !perfmon_capable()) 2249 return -EPERM; 2250 2251 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2252 * or btf, we need to check which one it is 2253 */ 2254 if (attr->attach_prog_fd) { 2255 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2256 if (IS_ERR(dst_prog)) { 2257 dst_prog = NULL; 2258 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2259 if (IS_ERR(attach_btf)) 2260 return -EINVAL; 2261 if (!btf_is_kernel(attach_btf)) { 2262 /* attaching through specifying bpf_prog's BTF 2263 * objects directly might be supported eventually 2264 */ 2265 btf_put(attach_btf); 2266 return -ENOTSUPP; 2267 } 2268 } 2269 } else if (attr->attach_btf_id) { 2270 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2271 attach_btf = bpf_get_btf_vmlinux(); 2272 if (IS_ERR(attach_btf)) 2273 return PTR_ERR(attach_btf); 2274 if (!attach_btf) 2275 return -EINVAL; 2276 btf_get(attach_btf); 2277 } 2278 2279 bpf_prog_load_fixup_attach_type(attr); 2280 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2281 attach_btf, attr->attach_btf_id, 2282 dst_prog)) { 2283 if (dst_prog) 2284 bpf_prog_put(dst_prog); 2285 if (attach_btf) 2286 btf_put(attach_btf); 2287 return -EINVAL; 2288 } 2289 2290 /* plain bpf_prog allocation */ 2291 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2292 if (!prog) { 2293 if (dst_prog) 2294 bpf_prog_put(dst_prog); 2295 if (attach_btf) 2296 btf_put(attach_btf); 2297 return -ENOMEM; 2298 } 2299 2300 prog->expected_attach_type = attr->expected_attach_type; 2301 prog->aux->attach_btf = attach_btf; 2302 prog->aux->attach_btf_id = attr->attach_btf_id; 2303 prog->aux->dst_prog = dst_prog; 2304 prog->aux->offload_requested = !!attr->prog_ifindex; 2305 prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; 2306 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 2307 2308 err = security_bpf_prog_alloc(prog->aux); 2309 if (err) 2310 goto free_prog; 2311 2312 prog->aux->user = get_current_user(); 2313 prog->len = attr->insn_cnt; 2314 2315 err = -EFAULT; 2316 if (copy_from_bpfptr(prog->insns, 2317 make_bpfptr(attr->insns, uattr.is_kernel), 2318 bpf_prog_insn_size(prog)) != 0) 2319 goto free_prog_sec; 2320 2321 prog->orig_prog = NULL; 2322 prog->jited = 0; 2323 2324 atomic64_set(&prog->aux->refcnt, 1); 2325 prog->gpl_compatible = is_gpl ? 1 : 0; 2326 2327 if (bpf_prog_is_dev_bound(prog->aux)) { 2328 err = bpf_prog_offload_init(prog, attr); 2329 if (err) 2330 goto free_prog_sec; 2331 } 2332 2333 /* find program type: socket_filter vs tracing_filter */ 2334 err = find_prog_type(type, prog); 2335 if (err < 0) 2336 goto free_prog_sec; 2337 2338 prog->aux->load_time = ktime_get_boottime_ns(); 2339 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2340 sizeof(attr->prog_name)); 2341 if (err < 0) 2342 goto free_prog_sec; 2343 2344 /* run eBPF verifier */ 2345 err = bpf_check(&prog, attr, uattr); 2346 if (err < 0) 2347 goto free_used_maps; 2348 2349 prog = bpf_prog_select_runtime(prog, &err); 2350 if (err < 0) 2351 goto free_used_maps; 2352 2353 err = bpf_prog_alloc_id(prog); 2354 if (err) 2355 goto free_used_maps; 2356 2357 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2358 * effectively publicly exposed. However, retrieving via 2359 * bpf_prog_get_fd_by_id() will take another reference, 2360 * therefore it cannot be gone underneath us. 2361 * 2362 * Only for the time /after/ successful bpf_prog_new_fd() 2363 * and before returning to userspace, we might just hold 2364 * one reference and any parallel close on that fd could 2365 * rip everything out. Hence, below notifications must 2366 * happen before bpf_prog_new_fd(). 2367 * 2368 * Also, any failure handling from this point onwards must 2369 * be using bpf_prog_put() given the program is exposed. 2370 */ 2371 bpf_prog_kallsyms_add(prog); 2372 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2373 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2374 2375 err = bpf_prog_new_fd(prog); 2376 if (err < 0) 2377 bpf_prog_put(prog); 2378 return err; 2379 2380 free_used_maps: 2381 /* In case we have subprogs, we need to wait for a grace 2382 * period before we can tear down JIT memory since symbols 2383 * are already exposed under kallsyms. 2384 */ 2385 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2386 return err; 2387 free_prog_sec: 2388 free_uid(prog->aux->user); 2389 security_bpf_prog_free(prog->aux); 2390 free_prog: 2391 if (prog->aux->attach_btf) 2392 btf_put(prog->aux->attach_btf); 2393 bpf_prog_free(prog); 2394 return err; 2395 } 2396 2397 #define BPF_OBJ_LAST_FIELD file_flags 2398 2399 static int bpf_obj_pin(const union bpf_attr *attr) 2400 { 2401 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2402 return -EINVAL; 2403 2404 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2405 } 2406 2407 static int bpf_obj_get(const union bpf_attr *attr) 2408 { 2409 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2410 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2411 return -EINVAL; 2412 2413 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2414 attr->file_flags); 2415 } 2416 2417 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2418 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2419 { 2420 atomic64_set(&link->refcnt, 1); 2421 link->type = type; 2422 link->id = 0; 2423 link->ops = ops; 2424 link->prog = prog; 2425 } 2426 2427 static void bpf_link_free_id(int id) 2428 { 2429 if (!id) 2430 return; 2431 2432 spin_lock_bh(&link_idr_lock); 2433 idr_remove(&link_idr, id); 2434 spin_unlock_bh(&link_idr_lock); 2435 } 2436 2437 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2438 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2439 * anon_inode's release() call. This helper marksbpf_link as 2440 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 2441 * is not decremented, it's the responsibility of a calling code that failed 2442 * to complete bpf_link initialization. 2443 */ 2444 void bpf_link_cleanup(struct bpf_link_primer *primer) 2445 { 2446 primer->link->prog = NULL; 2447 bpf_link_free_id(primer->id); 2448 fput(primer->file); 2449 put_unused_fd(primer->fd); 2450 } 2451 2452 void bpf_link_inc(struct bpf_link *link) 2453 { 2454 atomic64_inc(&link->refcnt); 2455 } 2456 2457 /* bpf_link_free is guaranteed to be called from process context */ 2458 static void bpf_link_free(struct bpf_link *link) 2459 { 2460 bpf_link_free_id(link->id); 2461 if (link->prog) { 2462 /* detach BPF program, clean up used resources */ 2463 link->ops->release(link); 2464 bpf_prog_put(link->prog); 2465 } 2466 /* free bpf_link and its containing memory */ 2467 link->ops->dealloc(link); 2468 } 2469 2470 static void bpf_link_put_deferred(struct work_struct *work) 2471 { 2472 struct bpf_link *link = container_of(work, struct bpf_link, work); 2473 2474 bpf_link_free(link); 2475 } 2476 2477 /* bpf_link_put can be called from atomic context, but ensures that resources 2478 * are freed from process context 2479 */ 2480 void bpf_link_put(struct bpf_link *link) 2481 { 2482 if (!atomic64_dec_and_test(&link->refcnt)) 2483 return; 2484 2485 if (in_atomic()) { 2486 INIT_WORK(&link->work, bpf_link_put_deferred); 2487 schedule_work(&link->work); 2488 } else { 2489 bpf_link_free(link); 2490 } 2491 } 2492 2493 static int bpf_link_release(struct inode *inode, struct file *filp) 2494 { 2495 struct bpf_link *link = filp->private_data; 2496 2497 bpf_link_put(link); 2498 return 0; 2499 } 2500 2501 #ifdef CONFIG_PROC_FS 2502 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 2503 #define BPF_MAP_TYPE(_id, _ops) 2504 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 2505 static const char *bpf_link_type_strs[] = { 2506 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 2507 #include <linux/bpf_types.h> 2508 }; 2509 #undef BPF_PROG_TYPE 2510 #undef BPF_MAP_TYPE 2511 #undef BPF_LINK_TYPE 2512 2513 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2514 { 2515 const struct bpf_link *link = filp->private_data; 2516 const struct bpf_prog *prog = link->prog; 2517 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2518 2519 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2520 seq_printf(m, 2521 "link_type:\t%s\n" 2522 "link_id:\t%u\n" 2523 "prog_tag:\t%s\n" 2524 "prog_id:\t%u\n", 2525 bpf_link_type_strs[link->type], 2526 link->id, 2527 prog_tag, 2528 prog->aux->id); 2529 if (link->ops->show_fdinfo) 2530 link->ops->show_fdinfo(link, m); 2531 } 2532 #endif 2533 2534 static const struct file_operations bpf_link_fops = { 2535 #ifdef CONFIG_PROC_FS 2536 .show_fdinfo = bpf_link_show_fdinfo, 2537 #endif 2538 .release = bpf_link_release, 2539 .read = bpf_dummy_read, 2540 .write = bpf_dummy_write, 2541 }; 2542 2543 static int bpf_link_alloc_id(struct bpf_link *link) 2544 { 2545 int id; 2546 2547 idr_preload(GFP_KERNEL); 2548 spin_lock_bh(&link_idr_lock); 2549 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 2550 spin_unlock_bh(&link_idr_lock); 2551 idr_preload_end(); 2552 2553 return id; 2554 } 2555 2556 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 2557 * reserving unused FD and allocating ID from link_idr. This is to be paired 2558 * with bpf_link_settle() to install FD and ID and expose bpf_link to 2559 * user-space, if bpf_link is successfully attached. If not, bpf_link and 2560 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 2561 * transient state is passed around in struct bpf_link_primer. 2562 * This is preferred way to create and initialize bpf_link, especially when 2563 * there are complicated and expensive operations inbetween creating bpf_link 2564 * itself and attaching it to BPF hook. By using bpf_link_prime() and 2565 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 2566 * expensive (and potentially failing) roll back operations in a rare case 2567 * that file, FD, or ID can't be allocated. 2568 */ 2569 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 2570 { 2571 struct file *file; 2572 int fd, id; 2573 2574 fd = get_unused_fd_flags(O_CLOEXEC); 2575 if (fd < 0) 2576 return fd; 2577 2578 2579 id = bpf_link_alloc_id(link); 2580 if (id < 0) { 2581 put_unused_fd(fd); 2582 return id; 2583 } 2584 2585 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2586 if (IS_ERR(file)) { 2587 bpf_link_free_id(id); 2588 put_unused_fd(fd); 2589 return PTR_ERR(file); 2590 } 2591 2592 primer->link = link; 2593 primer->file = file; 2594 primer->fd = fd; 2595 primer->id = id; 2596 return 0; 2597 } 2598 2599 int bpf_link_settle(struct bpf_link_primer *primer) 2600 { 2601 /* make bpf_link fetchable by ID */ 2602 spin_lock_bh(&link_idr_lock); 2603 primer->link->id = primer->id; 2604 spin_unlock_bh(&link_idr_lock); 2605 /* make bpf_link fetchable by FD */ 2606 fd_install(primer->fd, primer->file); 2607 /* pass through installed FD */ 2608 return primer->fd; 2609 } 2610 2611 int bpf_link_new_fd(struct bpf_link *link) 2612 { 2613 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2614 } 2615 2616 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2617 { 2618 struct fd f = fdget(ufd); 2619 struct bpf_link *link; 2620 2621 if (!f.file) 2622 return ERR_PTR(-EBADF); 2623 if (f.file->f_op != &bpf_link_fops) { 2624 fdput(f); 2625 return ERR_PTR(-EINVAL); 2626 } 2627 2628 link = f.file->private_data; 2629 bpf_link_inc(link); 2630 fdput(f); 2631 2632 return link; 2633 } 2634 2635 struct bpf_tracing_link { 2636 struct bpf_link link; 2637 enum bpf_attach_type attach_type; 2638 struct bpf_trampoline *trampoline; 2639 struct bpf_prog *tgt_prog; 2640 }; 2641 2642 static void bpf_tracing_link_release(struct bpf_link *link) 2643 { 2644 struct bpf_tracing_link *tr_link = 2645 container_of(link, struct bpf_tracing_link, link); 2646 2647 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, 2648 tr_link->trampoline)); 2649 2650 bpf_trampoline_put(tr_link->trampoline); 2651 2652 /* tgt_prog is NULL if target is a kernel function */ 2653 if (tr_link->tgt_prog) 2654 bpf_prog_put(tr_link->tgt_prog); 2655 } 2656 2657 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2658 { 2659 struct bpf_tracing_link *tr_link = 2660 container_of(link, struct bpf_tracing_link, link); 2661 2662 kfree(tr_link); 2663 } 2664 2665 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 2666 struct seq_file *seq) 2667 { 2668 struct bpf_tracing_link *tr_link = 2669 container_of(link, struct bpf_tracing_link, link); 2670 2671 seq_printf(seq, 2672 "attach_type:\t%d\n", 2673 tr_link->attach_type); 2674 } 2675 2676 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 2677 struct bpf_link_info *info) 2678 { 2679 struct bpf_tracing_link *tr_link = 2680 container_of(link, struct bpf_tracing_link, link); 2681 2682 info->tracing.attach_type = tr_link->attach_type; 2683 bpf_trampoline_unpack_key(tr_link->trampoline->key, 2684 &info->tracing.target_obj_id, 2685 &info->tracing.target_btf_id); 2686 2687 return 0; 2688 } 2689 2690 static const struct bpf_link_ops bpf_tracing_link_lops = { 2691 .release = bpf_tracing_link_release, 2692 .dealloc = bpf_tracing_link_dealloc, 2693 .show_fdinfo = bpf_tracing_link_show_fdinfo, 2694 .fill_link_info = bpf_tracing_link_fill_link_info, 2695 }; 2696 2697 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 2698 int tgt_prog_fd, 2699 u32 btf_id) 2700 { 2701 struct bpf_link_primer link_primer; 2702 struct bpf_prog *tgt_prog = NULL; 2703 struct bpf_trampoline *tr = NULL; 2704 struct bpf_tracing_link *link; 2705 u64 key = 0; 2706 int err; 2707 2708 switch (prog->type) { 2709 case BPF_PROG_TYPE_TRACING: 2710 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2711 prog->expected_attach_type != BPF_TRACE_FEXIT && 2712 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2713 err = -EINVAL; 2714 goto out_put_prog; 2715 } 2716 break; 2717 case BPF_PROG_TYPE_EXT: 2718 if (prog->expected_attach_type != 0) { 2719 err = -EINVAL; 2720 goto out_put_prog; 2721 } 2722 break; 2723 case BPF_PROG_TYPE_LSM: 2724 if (prog->expected_attach_type != BPF_LSM_MAC) { 2725 err = -EINVAL; 2726 goto out_put_prog; 2727 } 2728 break; 2729 default: 2730 err = -EINVAL; 2731 goto out_put_prog; 2732 } 2733 2734 if (!!tgt_prog_fd != !!btf_id) { 2735 err = -EINVAL; 2736 goto out_put_prog; 2737 } 2738 2739 if (tgt_prog_fd) { 2740 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */ 2741 if (prog->type != BPF_PROG_TYPE_EXT) { 2742 err = -EINVAL; 2743 goto out_put_prog; 2744 } 2745 2746 tgt_prog = bpf_prog_get(tgt_prog_fd); 2747 if (IS_ERR(tgt_prog)) { 2748 err = PTR_ERR(tgt_prog); 2749 tgt_prog = NULL; 2750 goto out_put_prog; 2751 } 2752 2753 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 2754 } 2755 2756 link = kzalloc(sizeof(*link), GFP_USER); 2757 if (!link) { 2758 err = -ENOMEM; 2759 goto out_put_prog; 2760 } 2761 bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, 2762 &bpf_tracing_link_lops, prog); 2763 link->attach_type = prog->expected_attach_type; 2764 2765 mutex_lock(&prog->aux->dst_mutex); 2766 2767 /* There are a few possible cases here: 2768 * 2769 * - if prog->aux->dst_trampoline is set, the program was just loaded 2770 * and not yet attached to anything, so we can use the values stored 2771 * in prog->aux 2772 * 2773 * - if prog->aux->dst_trampoline is NULL, the program has already been 2774 * attached to a target and its initial target was cleared (below) 2775 * 2776 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 2777 * target_btf_id using the link_create API. 2778 * 2779 * - if tgt_prog == NULL when this function was called using the old 2780 * raw_tracepoint_open API, and we need a target from prog->aux 2781 * 2782 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 2783 * was detached and is going for re-attachment. 2784 */ 2785 if (!prog->aux->dst_trampoline && !tgt_prog) { 2786 /* 2787 * Allow re-attach for TRACING and LSM programs. If it's 2788 * currently linked, bpf_trampoline_link_prog will fail. 2789 * EXT programs need to specify tgt_prog_fd, so they 2790 * re-attach in separate code path. 2791 */ 2792 if (prog->type != BPF_PROG_TYPE_TRACING && 2793 prog->type != BPF_PROG_TYPE_LSM) { 2794 err = -EINVAL; 2795 goto out_unlock; 2796 } 2797 btf_id = prog->aux->attach_btf_id; 2798 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 2799 } 2800 2801 if (!prog->aux->dst_trampoline || 2802 (key && key != prog->aux->dst_trampoline->key)) { 2803 /* If there is no saved target, or the specified target is 2804 * different from the destination specified at load time, we 2805 * need a new trampoline and a check for compatibility 2806 */ 2807 struct bpf_attach_target_info tgt_info = {}; 2808 2809 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 2810 &tgt_info); 2811 if (err) 2812 goto out_unlock; 2813 2814 tr = bpf_trampoline_get(key, &tgt_info); 2815 if (!tr) { 2816 err = -ENOMEM; 2817 goto out_unlock; 2818 } 2819 } else { 2820 /* The caller didn't specify a target, or the target was the 2821 * same as the destination supplied during program load. This 2822 * means we can reuse the trampoline and reference from program 2823 * load time, and there is no need to allocate a new one. This 2824 * can only happen once for any program, as the saved values in 2825 * prog->aux are cleared below. 2826 */ 2827 tr = prog->aux->dst_trampoline; 2828 tgt_prog = prog->aux->dst_prog; 2829 } 2830 2831 err = bpf_link_prime(&link->link, &link_primer); 2832 if (err) 2833 goto out_unlock; 2834 2835 err = bpf_trampoline_link_prog(prog, tr); 2836 if (err) { 2837 bpf_link_cleanup(&link_primer); 2838 link = NULL; 2839 goto out_unlock; 2840 } 2841 2842 link->tgt_prog = tgt_prog; 2843 link->trampoline = tr; 2844 2845 /* Always clear the trampoline and target prog from prog->aux to make 2846 * sure the original attach destination is not kept alive after a 2847 * program is (re-)attached to another target. 2848 */ 2849 if (prog->aux->dst_prog && 2850 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 2851 /* got extra prog ref from syscall, or attaching to different prog */ 2852 bpf_prog_put(prog->aux->dst_prog); 2853 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 2854 /* we allocated a new trampoline, so free the old one */ 2855 bpf_trampoline_put(prog->aux->dst_trampoline); 2856 2857 prog->aux->dst_prog = NULL; 2858 prog->aux->dst_trampoline = NULL; 2859 mutex_unlock(&prog->aux->dst_mutex); 2860 2861 return bpf_link_settle(&link_primer); 2862 out_unlock: 2863 if (tr && tr != prog->aux->dst_trampoline) 2864 bpf_trampoline_put(tr); 2865 mutex_unlock(&prog->aux->dst_mutex); 2866 kfree(link); 2867 out_put_prog: 2868 if (tgt_prog_fd && tgt_prog) 2869 bpf_prog_put(tgt_prog); 2870 return err; 2871 } 2872 2873 struct bpf_raw_tp_link { 2874 struct bpf_link link; 2875 struct bpf_raw_event_map *btp; 2876 }; 2877 2878 static void bpf_raw_tp_link_release(struct bpf_link *link) 2879 { 2880 struct bpf_raw_tp_link *raw_tp = 2881 container_of(link, struct bpf_raw_tp_link, link); 2882 2883 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2884 bpf_put_raw_tracepoint(raw_tp->btp); 2885 } 2886 2887 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2888 { 2889 struct bpf_raw_tp_link *raw_tp = 2890 container_of(link, struct bpf_raw_tp_link, link); 2891 2892 kfree(raw_tp); 2893 } 2894 2895 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 2896 struct seq_file *seq) 2897 { 2898 struct bpf_raw_tp_link *raw_tp_link = 2899 container_of(link, struct bpf_raw_tp_link, link); 2900 2901 seq_printf(seq, 2902 "tp_name:\t%s\n", 2903 raw_tp_link->btp->tp->name); 2904 } 2905 2906 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 2907 struct bpf_link_info *info) 2908 { 2909 struct bpf_raw_tp_link *raw_tp_link = 2910 container_of(link, struct bpf_raw_tp_link, link); 2911 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 2912 const char *tp_name = raw_tp_link->btp->tp->name; 2913 u32 ulen = info->raw_tracepoint.tp_name_len; 2914 size_t tp_len = strlen(tp_name); 2915 2916 if (!ulen ^ !ubuf) 2917 return -EINVAL; 2918 2919 info->raw_tracepoint.tp_name_len = tp_len + 1; 2920 2921 if (!ubuf) 2922 return 0; 2923 2924 if (ulen >= tp_len + 1) { 2925 if (copy_to_user(ubuf, tp_name, tp_len + 1)) 2926 return -EFAULT; 2927 } else { 2928 char zero = '\0'; 2929 2930 if (copy_to_user(ubuf, tp_name, ulen - 1)) 2931 return -EFAULT; 2932 if (put_user(zero, ubuf + ulen - 1)) 2933 return -EFAULT; 2934 return -ENOSPC; 2935 } 2936 2937 return 0; 2938 } 2939 2940 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 2941 .release = bpf_raw_tp_link_release, 2942 .dealloc = bpf_raw_tp_link_dealloc, 2943 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 2944 .fill_link_info = bpf_raw_tp_link_fill_link_info, 2945 }; 2946 2947 #ifdef CONFIG_PERF_EVENTS 2948 struct bpf_perf_link { 2949 struct bpf_link link; 2950 struct file *perf_file; 2951 }; 2952 2953 static void bpf_perf_link_release(struct bpf_link *link) 2954 { 2955 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2956 struct perf_event *event = perf_link->perf_file->private_data; 2957 2958 perf_event_free_bpf_prog(event); 2959 fput(perf_link->perf_file); 2960 } 2961 2962 static void bpf_perf_link_dealloc(struct bpf_link *link) 2963 { 2964 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2965 2966 kfree(perf_link); 2967 } 2968 2969 static const struct bpf_link_ops bpf_perf_link_lops = { 2970 .release = bpf_perf_link_release, 2971 .dealloc = bpf_perf_link_dealloc, 2972 }; 2973 2974 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 2975 { 2976 struct bpf_link_primer link_primer; 2977 struct bpf_perf_link *link; 2978 struct perf_event *event; 2979 struct file *perf_file; 2980 int err; 2981 2982 if (attr->link_create.flags) 2983 return -EINVAL; 2984 2985 perf_file = perf_event_get(attr->link_create.target_fd); 2986 if (IS_ERR(perf_file)) 2987 return PTR_ERR(perf_file); 2988 2989 link = kzalloc(sizeof(*link), GFP_USER); 2990 if (!link) { 2991 err = -ENOMEM; 2992 goto out_put_file; 2993 } 2994 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 2995 link->perf_file = perf_file; 2996 2997 err = bpf_link_prime(&link->link, &link_primer); 2998 if (err) { 2999 kfree(link); 3000 goto out_put_file; 3001 } 3002 3003 event = perf_file->private_data; 3004 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3005 if (err) { 3006 bpf_link_cleanup(&link_primer); 3007 goto out_put_file; 3008 } 3009 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3010 bpf_prog_inc(prog); 3011 3012 return bpf_link_settle(&link_primer); 3013 3014 out_put_file: 3015 fput(perf_file); 3016 return err; 3017 } 3018 #endif /* CONFIG_PERF_EVENTS */ 3019 3020 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 3021 3022 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3023 { 3024 struct bpf_link_primer link_primer; 3025 struct bpf_raw_tp_link *link; 3026 struct bpf_raw_event_map *btp; 3027 struct bpf_prog *prog; 3028 const char *tp_name; 3029 char buf[128]; 3030 int err; 3031 3032 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3033 return -EINVAL; 3034 3035 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3036 if (IS_ERR(prog)) 3037 return PTR_ERR(prog); 3038 3039 switch (prog->type) { 3040 case BPF_PROG_TYPE_TRACING: 3041 case BPF_PROG_TYPE_EXT: 3042 case BPF_PROG_TYPE_LSM: 3043 if (attr->raw_tracepoint.name) { 3044 /* The attach point for this category of programs 3045 * should be specified via btf_id during program load. 3046 */ 3047 err = -EINVAL; 3048 goto out_put_prog; 3049 } 3050 if (prog->type == BPF_PROG_TYPE_TRACING && 3051 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3052 tp_name = prog->aux->attach_func_name; 3053 break; 3054 } 3055 err = bpf_tracing_prog_attach(prog, 0, 0); 3056 if (err >= 0) 3057 return err; 3058 goto out_put_prog; 3059 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3060 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3061 if (strncpy_from_user(buf, 3062 u64_to_user_ptr(attr->raw_tracepoint.name), 3063 sizeof(buf) - 1) < 0) { 3064 err = -EFAULT; 3065 goto out_put_prog; 3066 } 3067 buf[sizeof(buf) - 1] = 0; 3068 tp_name = buf; 3069 break; 3070 default: 3071 err = -EINVAL; 3072 goto out_put_prog; 3073 } 3074 3075 btp = bpf_get_raw_tracepoint(tp_name); 3076 if (!btp) { 3077 err = -ENOENT; 3078 goto out_put_prog; 3079 } 3080 3081 link = kzalloc(sizeof(*link), GFP_USER); 3082 if (!link) { 3083 err = -ENOMEM; 3084 goto out_put_btp; 3085 } 3086 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3087 &bpf_raw_tp_link_lops, prog); 3088 link->btp = btp; 3089 3090 err = bpf_link_prime(&link->link, &link_primer); 3091 if (err) { 3092 kfree(link); 3093 goto out_put_btp; 3094 } 3095 3096 err = bpf_probe_register(link->btp, prog); 3097 if (err) { 3098 bpf_link_cleanup(&link_primer); 3099 goto out_put_btp; 3100 } 3101 3102 return bpf_link_settle(&link_primer); 3103 3104 out_put_btp: 3105 bpf_put_raw_tracepoint(btp); 3106 out_put_prog: 3107 bpf_prog_put(prog); 3108 return err; 3109 } 3110 3111 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3112 enum bpf_attach_type attach_type) 3113 { 3114 switch (prog->type) { 3115 case BPF_PROG_TYPE_CGROUP_SOCK: 3116 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3117 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3118 case BPF_PROG_TYPE_SK_LOOKUP: 3119 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3120 case BPF_PROG_TYPE_CGROUP_SKB: 3121 if (!capable(CAP_NET_ADMIN)) 3122 /* cg-skb progs can be loaded by unpriv user. 3123 * check permissions at attach time. 3124 */ 3125 return -EPERM; 3126 return prog->enforce_expected_attach_type && 3127 prog->expected_attach_type != attach_type ? 3128 -EINVAL : 0; 3129 default: 3130 return 0; 3131 } 3132 } 3133 3134 static enum bpf_prog_type 3135 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3136 { 3137 switch (attach_type) { 3138 case BPF_CGROUP_INET_INGRESS: 3139 case BPF_CGROUP_INET_EGRESS: 3140 return BPF_PROG_TYPE_CGROUP_SKB; 3141 case BPF_CGROUP_INET_SOCK_CREATE: 3142 case BPF_CGROUP_INET_SOCK_RELEASE: 3143 case BPF_CGROUP_INET4_POST_BIND: 3144 case BPF_CGROUP_INET6_POST_BIND: 3145 return BPF_PROG_TYPE_CGROUP_SOCK; 3146 case BPF_CGROUP_INET4_BIND: 3147 case BPF_CGROUP_INET6_BIND: 3148 case BPF_CGROUP_INET4_CONNECT: 3149 case BPF_CGROUP_INET6_CONNECT: 3150 case BPF_CGROUP_INET4_GETPEERNAME: 3151 case BPF_CGROUP_INET6_GETPEERNAME: 3152 case BPF_CGROUP_INET4_GETSOCKNAME: 3153 case BPF_CGROUP_INET6_GETSOCKNAME: 3154 case BPF_CGROUP_UDP4_SENDMSG: 3155 case BPF_CGROUP_UDP6_SENDMSG: 3156 case BPF_CGROUP_UDP4_RECVMSG: 3157 case BPF_CGROUP_UDP6_RECVMSG: 3158 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3159 case BPF_CGROUP_SOCK_OPS: 3160 return BPF_PROG_TYPE_SOCK_OPS; 3161 case BPF_CGROUP_DEVICE: 3162 return BPF_PROG_TYPE_CGROUP_DEVICE; 3163 case BPF_SK_MSG_VERDICT: 3164 return BPF_PROG_TYPE_SK_MSG; 3165 case BPF_SK_SKB_STREAM_PARSER: 3166 case BPF_SK_SKB_STREAM_VERDICT: 3167 case BPF_SK_SKB_VERDICT: 3168 return BPF_PROG_TYPE_SK_SKB; 3169 case BPF_LIRC_MODE2: 3170 return BPF_PROG_TYPE_LIRC_MODE2; 3171 case BPF_FLOW_DISSECTOR: 3172 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3173 case BPF_CGROUP_SYSCTL: 3174 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3175 case BPF_CGROUP_GETSOCKOPT: 3176 case BPF_CGROUP_SETSOCKOPT: 3177 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3178 case BPF_TRACE_ITER: 3179 return BPF_PROG_TYPE_TRACING; 3180 case BPF_SK_LOOKUP: 3181 return BPF_PROG_TYPE_SK_LOOKUP; 3182 case BPF_XDP: 3183 return BPF_PROG_TYPE_XDP; 3184 default: 3185 return BPF_PROG_TYPE_UNSPEC; 3186 } 3187 } 3188 3189 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 3190 3191 #define BPF_F_ATTACH_MASK \ 3192 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 3193 3194 static int bpf_prog_attach(const union bpf_attr *attr) 3195 { 3196 enum bpf_prog_type ptype; 3197 struct bpf_prog *prog; 3198 int ret; 3199 3200 if (CHECK_ATTR(BPF_PROG_ATTACH)) 3201 return -EINVAL; 3202 3203 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 3204 return -EINVAL; 3205 3206 ptype = attach_type_to_prog_type(attr->attach_type); 3207 if (ptype == BPF_PROG_TYPE_UNSPEC) 3208 return -EINVAL; 3209 3210 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 3211 if (IS_ERR(prog)) 3212 return PTR_ERR(prog); 3213 3214 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 3215 bpf_prog_put(prog); 3216 return -EINVAL; 3217 } 3218 3219 switch (ptype) { 3220 case BPF_PROG_TYPE_SK_SKB: 3221 case BPF_PROG_TYPE_SK_MSG: 3222 ret = sock_map_get_from_fd(attr, prog); 3223 break; 3224 case BPF_PROG_TYPE_LIRC_MODE2: 3225 ret = lirc_prog_attach(attr, prog); 3226 break; 3227 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3228 ret = netns_bpf_prog_attach(attr, prog); 3229 break; 3230 case BPF_PROG_TYPE_CGROUP_DEVICE: 3231 case BPF_PROG_TYPE_CGROUP_SKB: 3232 case BPF_PROG_TYPE_CGROUP_SOCK: 3233 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3234 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3235 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3236 case BPF_PROG_TYPE_SOCK_OPS: 3237 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 3238 break; 3239 default: 3240 ret = -EINVAL; 3241 } 3242 3243 if (ret) 3244 bpf_prog_put(prog); 3245 return ret; 3246 } 3247 3248 #define BPF_PROG_DETACH_LAST_FIELD attach_type 3249 3250 static int bpf_prog_detach(const union bpf_attr *attr) 3251 { 3252 enum bpf_prog_type ptype; 3253 3254 if (CHECK_ATTR(BPF_PROG_DETACH)) 3255 return -EINVAL; 3256 3257 ptype = attach_type_to_prog_type(attr->attach_type); 3258 3259 switch (ptype) { 3260 case BPF_PROG_TYPE_SK_MSG: 3261 case BPF_PROG_TYPE_SK_SKB: 3262 return sock_map_prog_detach(attr, ptype); 3263 case BPF_PROG_TYPE_LIRC_MODE2: 3264 return lirc_prog_detach(attr); 3265 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3266 return netns_bpf_prog_detach(attr, ptype); 3267 case BPF_PROG_TYPE_CGROUP_DEVICE: 3268 case BPF_PROG_TYPE_CGROUP_SKB: 3269 case BPF_PROG_TYPE_CGROUP_SOCK: 3270 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3271 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3272 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3273 case BPF_PROG_TYPE_SOCK_OPS: 3274 return cgroup_bpf_prog_detach(attr, ptype); 3275 default: 3276 return -EINVAL; 3277 } 3278 } 3279 3280 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 3281 3282 static int bpf_prog_query(const union bpf_attr *attr, 3283 union bpf_attr __user *uattr) 3284 { 3285 if (!capable(CAP_NET_ADMIN)) 3286 return -EPERM; 3287 if (CHECK_ATTR(BPF_PROG_QUERY)) 3288 return -EINVAL; 3289 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 3290 return -EINVAL; 3291 3292 switch (attr->query.attach_type) { 3293 case BPF_CGROUP_INET_INGRESS: 3294 case BPF_CGROUP_INET_EGRESS: 3295 case BPF_CGROUP_INET_SOCK_CREATE: 3296 case BPF_CGROUP_INET_SOCK_RELEASE: 3297 case BPF_CGROUP_INET4_BIND: 3298 case BPF_CGROUP_INET6_BIND: 3299 case BPF_CGROUP_INET4_POST_BIND: 3300 case BPF_CGROUP_INET6_POST_BIND: 3301 case BPF_CGROUP_INET4_CONNECT: 3302 case BPF_CGROUP_INET6_CONNECT: 3303 case BPF_CGROUP_INET4_GETPEERNAME: 3304 case BPF_CGROUP_INET6_GETPEERNAME: 3305 case BPF_CGROUP_INET4_GETSOCKNAME: 3306 case BPF_CGROUP_INET6_GETSOCKNAME: 3307 case BPF_CGROUP_UDP4_SENDMSG: 3308 case BPF_CGROUP_UDP6_SENDMSG: 3309 case BPF_CGROUP_UDP4_RECVMSG: 3310 case BPF_CGROUP_UDP6_RECVMSG: 3311 case BPF_CGROUP_SOCK_OPS: 3312 case BPF_CGROUP_DEVICE: 3313 case BPF_CGROUP_SYSCTL: 3314 case BPF_CGROUP_GETSOCKOPT: 3315 case BPF_CGROUP_SETSOCKOPT: 3316 return cgroup_bpf_prog_query(attr, uattr); 3317 case BPF_LIRC_MODE2: 3318 return lirc_prog_query(attr, uattr); 3319 case BPF_FLOW_DISSECTOR: 3320 case BPF_SK_LOOKUP: 3321 return netns_bpf_prog_query(attr, uattr); 3322 case BPF_SK_SKB_STREAM_PARSER: 3323 case BPF_SK_SKB_STREAM_VERDICT: 3324 case BPF_SK_MSG_VERDICT: 3325 case BPF_SK_SKB_VERDICT: 3326 return sock_map_bpf_prog_query(attr, uattr); 3327 default: 3328 return -EINVAL; 3329 } 3330 } 3331 3332 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu 3333 3334 static int bpf_prog_test_run(const union bpf_attr *attr, 3335 union bpf_attr __user *uattr) 3336 { 3337 struct bpf_prog *prog; 3338 int ret = -ENOTSUPP; 3339 3340 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 3341 return -EINVAL; 3342 3343 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 3344 (!attr->test.ctx_size_in && attr->test.ctx_in)) 3345 return -EINVAL; 3346 3347 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 3348 (!attr->test.ctx_size_out && attr->test.ctx_out)) 3349 return -EINVAL; 3350 3351 prog = bpf_prog_get(attr->test.prog_fd); 3352 if (IS_ERR(prog)) 3353 return PTR_ERR(prog); 3354 3355 if (prog->aux->ops->test_run) 3356 ret = prog->aux->ops->test_run(prog, attr, uattr); 3357 3358 bpf_prog_put(prog); 3359 return ret; 3360 } 3361 3362 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 3363 3364 static int bpf_obj_get_next_id(const union bpf_attr *attr, 3365 union bpf_attr __user *uattr, 3366 struct idr *idr, 3367 spinlock_t *lock) 3368 { 3369 u32 next_id = attr->start_id; 3370 int err = 0; 3371 3372 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 3373 return -EINVAL; 3374 3375 if (!capable(CAP_SYS_ADMIN)) 3376 return -EPERM; 3377 3378 next_id++; 3379 spin_lock_bh(lock); 3380 if (!idr_get_next(idr, &next_id)) 3381 err = -ENOENT; 3382 spin_unlock_bh(lock); 3383 3384 if (!err) 3385 err = put_user(next_id, &uattr->next_id); 3386 3387 return err; 3388 } 3389 3390 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 3391 { 3392 struct bpf_map *map; 3393 3394 spin_lock_bh(&map_idr_lock); 3395 again: 3396 map = idr_get_next(&map_idr, id); 3397 if (map) { 3398 map = __bpf_map_inc_not_zero(map, false); 3399 if (IS_ERR(map)) { 3400 (*id)++; 3401 goto again; 3402 } 3403 } 3404 spin_unlock_bh(&map_idr_lock); 3405 3406 return map; 3407 } 3408 3409 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 3410 { 3411 struct bpf_prog *prog; 3412 3413 spin_lock_bh(&prog_idr_lock); 3414 again: 3415 prog = idr_get_next(&prog_idr, id); 3416 if (prog) { 3417 prog = bpf_prog_inc_not_zero(prog); 3418 if (IS_ERR(prog)) { 3419 (*id)++; 3420 goto again; 3421 } 3422 } 3423 spin_unlock_bh(&prog_idr_lock); 3424 3425 return prog; 3426 } 3427 3428 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 3429 3430 struct bpf_prog *bpf_prog_by_id(u32 id) 3431 { 3432 struct bpf_prog *prog; 3433 3434 if (!id) 3435 return ERR_PTR(-ENOENT); 3436 3437 spin_lock_bh(&prog_idr_lock); 3438 prog = idr_find(&prog_idr, id); 3439 if (prog) 3440 prog = bpf_prog_inc_not_zero(prog); 3441 else 3442 prog = ERR_PTR(-ENOENT); 3443 spin_unlock_bh(&prog_idr_lock); 3444 return prog; 3445 } 3446 3447 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 3448 { 3449 struct bpf_prog *prog; 3450 u32 id = attr->prog_id; 3451 int fd; 3452 3453 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 3454 return -EINVAL; 3455 3456 if (!capable(CAP_SYS_ADMIN)) 3457 return -EPERM; 3458 3459 prog = bpf_prog_by_id(id); 3460 if (IS_ERR(prog)) 3461 return PTR_ERR(prog); 3462 3463 fd = bpf_prog_new_fd(prog); 3464 if (fd < 0) 3465 bpf_prog_put(prog); 3466 3467 return fd; 3468 } 3469 3470 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 3471 3472 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 3473 { 3474 struct bpf_map *map; 3475 u32 id = attr->map_id; 3476 int f_flags; 3477 int fd; 3478 3479 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 3480 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 3481 return -EINVAL; 3482 3483 if (!capable(CAP_SYS_ADMIN)) 3484 return -EPERM; 3485 3486 f_flags = bpf_get_file_flag(attr->open_flags); 3487 if (f_flags < 0) 3488 return f_flags; 3489 3490 spin_lock_bh(&map_idr_lock); 3491 map = idr_find(&map_idr, id); 3492 if (map) 3493 map = __bpf_map_inc_not_zero(map, true); 3494 else 3495 map = ERR_PTR(-ENOENT); 3496 spin_unlock_bh(&map_idr_lock); 3497 3498 if (IS_ERR(map)) 3499 return PTR_ERR(map); 3500 3501 fd = bpf_map_new_fd(map, f_flags); 3502 if (fd < 0) 3503 bpf_map_put_with_uref(map); 3504 3505 return fd; 3506 } 3507 3508 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 3509 unsigned long addr, u32 *off, 3510 u32 *type) 3511 { 3512 const struct bpf_map *map; 3513 int i; 3514 3515 mutex_lock(&prog->aux->used_maps_mutex); 3516 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 3517 map = prog->aux->used_maps[i]; 3518 if (map == (void *)addr) { 3519 *type = BPF_PSEUDO_MAP_FD; 3520 goto out; 3521 } 3522 if (!map->ops->map_direct_value_meta) 3523 continue; 3524 if (!map->ops->map_direct_value_meta(map, addr, off)) { 3525 *type = BPF_PSEUDO_MAP_VALUE; 3526 goto out; 3527 } 3528 } 3529 map = NULL; 3530 3531 out: 3532 mutex_unlock(&prog->aux->used_maps_mutex); 3533 return map; 3534 } 3535 3536 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 3537 const struct cred *f_cred) 3538 { 3539 const struct bpf_map *map; 3540 struct bpf_insn *insns; 3541 u32 off, type; 3542 u64 imm; 3543 u8 code; 3544 int i; 3545 3546 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 3547 GFP_USER); 3548 if (!insns) 3549 return insns; 3550 3551 for (i = 0; i < prog->len; i++) { 3552 code = insns[i].code; 3553 3554 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 3555 insns[i].code = BPF_JMP | BPF_CALL; 3556 insns[i].imm = BPF_FUNC_tail_call; 3557 /* fall-through */ 3558 } 3559 if (code == (BPF_JMP | BPF_CALL) || 3560 code == (BPF_JMP | BPF_CALL_ARGS)) { 3561 if (code == (BPF_JMP | BPF_CALL_ARGS)) 3562 insns[i].code = BPF_JMP | BPF_CALL; 3563 if (!bpf_dump_raw_ok(f_cred)) 3564 insns[i].imm = 0; 3565 continue; 3566 } 3567 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 3568 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 3569 continue; 3570 } 3571 3572 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 3573 continue; 3574 3575 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 3576 map = bpf_map_from_imm(prog, imm, &off, &type); 3577 if (map) { 3578 insns[i].src_reg = type; 3579 insns[i].imm = map->id; 3580 insns[i + 1].imm = off; 3581 continue; 3582 } 3583 } 3584 3585 return insns; 3586 } 3587 3588 static int set_info_rec_size(struct bpf_prog_info *info) 3589 { 3590 /* 3591 * Ensure info.*_rec_size is the same as kernel expected size 3592 * 3593 * or 3594 * 3595 * Only allow zero *_rec_size if both _rec_size and _cnt are 3596 * zero. In this case, the kernel will set the expected 3597 * _rec_size back to the info. 3598 */ 3599 3600 if ((info->nr_func_info || info->func_info_rec_size) && 3601 info->func_info_rec_size != sizeof(struct bpf_func_info)) 3602 return -EINVAL; 3603 3604 if ((info->nr_line_info || info->line_info_rec_size) && 3605 info->line_info_rec_size != sizeof(struct bpf_line_info)) 3606 return -EINVAL; 3607 3608 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 3609 info->jited_line_info_rec_size != sizeof(__u64)) 3610 return -EINVAL; 3611 3612 info->func_info_rec_size = sizeof(struct bpf_func_info); 3613 info->line_info_rec_size = sizeof(struct bpf_line_info); 3614 info->jited_line_info_rec_size = sizeof(__u64); 3615 3616 return 0; 3617 } 3618 3619 static int bpf_prog_get_info_by_fd(struct file *file, 3620 struct bpf_prog *prog, 3621 const union bpf_attr *attr, 3622 union bpf_attr __user *uattr) 3623 { 3624 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3625 struct bpf_prog_info info; 3626 u32 info_len = attr->info.info_len; 3627 struct bpf_prog_kstats stats; 3628 char __user *uinsns; 3629 u32 ulen; 3630 int err; 3631 3632 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3633 if (err) 3634 return err; 3635 info_len = min_t(u32, sizeof(info), info_len); 3636 3637 memset(&info, 0, sizeof(info)); 3638 if (copy_from_user(&info, uinfo, info_len)) 3639 return -EFAULT; 3640 3641 info.type = prog->type; 3642 info.id = prog->aux->id; 3643 info.load_time = prog->aux->load_time; 3644 info.created_by_uid = from_kuid_munged(current_user_ns(), 3645 prog->aux->user->uid); 3646 info.gpl_compatible = prog->gpl_compatible; 3647 3648 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3649 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3650 3651 mutex_lock(&prog->aux->used_maps_mutex); 3652 ulen = info.nr_map_ids; 3653 info.nr_map_ids = prog->aux->used_map_cnt; 3654 ulen = min_t(u32, info.nr_map_ids, ulen); 3655 if (ulen) { 3656 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3657 u32 i; 3658 3659 for (i = 0; i < ulen; i++) 3660 if (put_user(prog->aux->used_maps[i]->id, 3661 &user_map_ids[i])) { 3662 mutex_unlock(&prog->aux->used_maps_mutex); 3663 return -EFAULT; 3664 } 3665 } 3666 mutex_unlock(&prog->aux->used_maps_mutex); 3667 3668 err = set_info_rec_size(&info); 3669 if (err) 3670 return err; 3671 3672 bpf_prog_get_stats(prog, &stats); 3673 info.run_time_ns = stats.nsecs; 3674 info.run_cnt = stats.cnt; 3675 info.recursion_misses = stats.misses; 3676 3677 info.verified_insns = prog->aux->verified_insns; 3678 3679 if (!bpf_capable()) { 3680 info.jited_prog_len = 0; 3681 info.xlated_prog_len = 0; 3682 info.nr_jited_ksyms = 0; 3683 info.nr_jited_func_lens = 0; 3684 info.nr_func_info = 0; 3685 info.nr_line_info = 0; 3686 info.nr_jited_line_info = 0; 3687 goto done; 3688 } 3689 3690 ulen = info.xlated_prog_len; 3691 info.xlated_prog_len = bpf_prog_insn_size(prog); 3692 if (info.xlated_prog_len && ulen) { 3693 struct bpf_insn *insns_sanitized; 3694 bool fault; 3695 3696 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 3697 info.xlated_prog_insns = 0; 3698 goto done; 3699 } 3700 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 3701 if (!insns_sanitized) 3702 return -ENOMEM; 3703 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3704 ulen = min_t(u32, info.xlated_prog_len, ulen); 3705 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3706 kfree(insns_sanitized); 3707 if (fault) 3708 return -EFAULT; 3709 } 3710 3711 if (bpf_prog_is_dev_bound(prog->aux)) { 3712 err = bpf_prog_offload_info_fill(&info, prog); 3713 if (err) 3714 return err; 3715 goto done; 3716 } 3717 3718 /* NOTE: the following code is supposed to be skipped for offload. 3719 * bpf_prog_offload_info_fill() is the place to fill similar fields 3720 * for offload. 3721 */ 3722 ulen = info.jited_prog_len; 3723 if (prog->aux->func_cnt) { 3724 u32 i; 3725 3726 info.jited_prog_len = 0; 3727 for (i = 0; i < prog->aux->func_cnt; i++) 3728 info.jited_prog_len += prog->aux->func[i]->jited_len; 3729 } else { 3730 info.jited_prog_len = prog->jited_len; 3731 } 3732 3733 if (info.jited_prog_len && ulen) { 3734 if (bpf_dump_raw_ok(file->f_cred)) { 3735 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3736 ulen = min_t(u32, info.jited_prog_len, ulen); 3737 3738 /* for multi-function programs, copy the JITed 3739 * instructions for all the functions 3740 */ 3741 if (prog->aux->func_cnt) { 3742 u32 len, free, i; 3743 u8 *img; 3744 3745 free = ulen; 3746 for (i = 0; i < prog->aux->func_cnt; i++) { 3747 len = prog->aux->func[i]->jited_len; 3748 len = min_t(u32, len, free); 3749 img = (u8 *) prog->aux->func[i]->bpf_func; 3750 if (copy_to_user(uinsns, img, len)) 3751 return -EFAULT; 3752 uinsns += len; 3753 free -= len; 3754 if (!free) 3755 break; 3756 } 3757 } else { 3758 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3759 return -EFAULT; 3760 } 3761 } else { 3762 info.jited_prog_insns = 0; 3763 } 3764 } 3765 3766 ulen = info.nr_jited_ksyms; 3767 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3768 if (ulen) { 3769 if (bpf_dump_raw_ok(file->f_cred)) { 3770 unsigned long ksym_addr; 3771 u64 __user *user_ksyms; 3772 u32 i; 3773 3774 /* copy the address of the kernel symbol 3775 * corresponding to each function 3776 */ 3777 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3778 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3779 if (prog->aux->func_cnt) { 3780 for (i = 0; i < ulen; i++) { 3781 ksym_addr = (unsigned long) 3782 prog->aux->func[i]->bpf_func; 3783 if (put_user((u64) ksym_addr, 3784 &user_ksyms[i])) 3785 return -EFAULT; 3786 } 3787 } else { 3788 ksym_addr = (unsigned long) prog->bpf_func; 3789 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3790 return -EFAULT; 3791 } 3792 } else { 3793 info.jited_ksyms = 0; 3794 } 3795 } 3796 3797 ulen = info.nr_jited_func_lens; 3798 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3799 if (ulen) { 3800 if (bpf_dump_raw_ok(file->f_cred)) { 3801 u32 __user *user_lens; 3802 u32 func_len, i; 3803 3804 /* copy the JITed image lengths for each function */ 3805 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3806 user_lens = u64_to_user_ptr(info.jited_func_lens); 3807 if (prog->aux->func_cnt) { 3808 for (i = 0; i < ulen; i++) { 3809 func_len = 3810 prog->aux->func[i]->jited_len; 3811 if (put_user(func_len, &user_lens[i])) 3812 return -EFAULT; 3813 } 3814 } else { 3815 func_len = prog->jited_len; 3816 if (put_user(func_len, &user_lens[0])) 3817 return -EFAULT; 3818 } 3819 } else { 3820 info.jited_func_lens = 0; 3821 } 3822 } 3823 3824 if (prog->aux->btf) 3825 info.btf_id = btf_obj_id(prog->aux->btf); 3826 3827 ulen = info.nr_func_info; 3828 info.nr_func_info = prog->aux->func_info_cnt; 3829 if (info.nr_func_info && ulen) { 3830 char __user *user_finfo; 3831 3832 user_finfo = u64_to_user_ptr(info.func_info); 3833 ulen = min_t(u32, info.nr_func_info, ulen); 3834 if (copy_to_user(user_finfo, prog->aux->func_info, 3835 info.func_info_rec_size * ulen)) 3836 return -EFAULT; 3837 } 3838 3839 ulen = info.nr_line_info; 3840 info.nr_line_info = prog->aux->nr_linfo; 3841 if (info.nr_line_info && ulen) { 3842 __u8 __user *user_linfo; 3843 3844 user_linfo = u64_to_user_ptr(info.line_info); 3845 ulen = min_t(u32, info.nr_line_info, ulen); 3846 if (copy_to_user(user_linfo, prog->aux->linfo, 3847 info.line_info_rec_size * ulen)) 3848 return -EFAULT; 3849 } 3850 3851 ulen = info.nr_jited_line_info; 3852 if (prog->aux->jited_linfo) 3853 info.nr_jited_line_info = prog->aux->nr_linfo; 3854 else 3855 info.nr_jited_line_info = 0; 3856 if (info.nr_jited_line_info && ulen) { 3857 if (bpf_dump_raw_ok(file->f_cred)) { 3858 __u64 __user *user_linfo; 3859 u32 i; 3860 3861 user_linfo = u64_to_user_ptr(info.jited_line_info); 3862 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3863 for (i = 0; i < ulen; i++) { 3864 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3865 &user_linfo[i])) 3866 return -EFAULT; 3867 } 3868 } else { 3869 info.jited_line_info = 0; 3870 } 3871 } 3872 3873 ulen = info.nr_prog_tags; 3874 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3875 if (ulen) { 3876 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3877 u32 i; 3878 3879 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3880 ulen = min_t(u32, info.nr_prog_tags, ulen); 3881 if (prog->aux->func_cnt) { 3882 for (i = 0; i < ulen; i++) { 3883 if (copy_to_user(user_prog_tags[i], 3884 prog->aux->func[i]->tag, 3885 BPF_TAG_SIZE)) 3886 return -EFAULT; 3887 } 3888 } else { 3889 if (copy_to_user(user_prog_tags[0], 3890 prog->tag, BPF_TAG_SIZE)) 3891 return -EFAULT; 3892 } 3893 } 3894 3895 done: 3896 if (copy_to_user(uinfo, &info, info_len) || 3897 put_user(info_len, &uattr->info.info_len)) 3898 return -EFAULT; 3899 3900 return 0; 3901 } 3902 3903 static int bpf_map_get_info_by_fd(struct file *file, 3904 struct bpf_map *map, 3905 const union bpf_attr *attr, 3906 union bpf_attr __user *uattr) 3907 { 3908 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3909 struct bpf_map_info info; 3910 u32 info_len = attr->info.info_len; 3911 int err; 3912 3913 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3914 if (err) 3915 return err; 3916 info_len = min_t(u32, sizeof(info), info_len); 3917 3918 memset(&info, 0, sizeof(info)); 3919 info.type = map->map_type; 3920 info.id = map->id; 3921 info.key_size = map->key_size; 3922 info.value_size = map->value_size; 3923 info.max_entries = map->max_entries; 3924 info.map_flags = map->map_flags; 3925 info.map_extra = map->map_extra; 3926 memcpy(info.name, map->name, sizeof(map->name)); 3927 3928 if (map->btf) { 3929 info.btf_id = btf_obj_id(map->btf); 3930 info.btf_key_type_id = map->btf_key_type_id; 3931 info.btf_value_type_id = map->btf_value_type_id; 3932 } 3933 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3934 3935 if (bpf_map_is_dev_bound(map)) { 3936 err = bpf_map_offload_info_fill(&info, map); 3937 if (err) 3938 return err; 3939 } 3940 3941 if (copy_to_user(uinfo, &info, info_len) || 3942 put_user(info_len, &uattr->info.info_len)) 3943 return -EFAULT; 3944 3945 return 0; 3946 } 3947 3948 static int bpf_btf_get_info_by_fd(struct file *file, 3949 struct btf *btf, 3950 const union bpf_attr *attr, 3951 union bpf_attr __user *uattr) 3952 { 3953 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3954 u32 info_len = attr->info.info_len; 3955 int err; 3956 3957 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 3958 if (err) 3959 return err; 3960 3961 return btf_get_info_by_fd(btf, attr, uattr); 3962 } 3963 3964 static int bpf_link_get_info_by_fd(struct file *file, 3965 struct bpf_link *link, 3966 const union bpf_attr *attr, 3967 union bpf_attr __user *uattr) 3968 { 3969 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3970 struct bpf_link_info info; 3971 u32 info_len = attr->info.info_len; 3972 int err; 3973 3974 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3975 if (err) 3976 return err; 3977 info_len = min_t(u32, sizeof(info), info_len); 3978 3979 memset(&info, 0, sizeof(info)); 3980 if (copy_from_user(&info, uinfo, info_len)) 3981 return -EFAULT; 3982 3983 info.type = link->type; 3984 info.id = link->id; 3985 info.prog_id = link->prog->aux->id; 3986 3987 if (link->ops->fill_link_info) { 3988 err = link->ops->fill_link_info(link, &info); 3989 if (err) 3990 return err; 3991 } 3992 3993 if (copy_to_user(uinfo, &info, info_len) || 3994 put_user(info_len, &uattr->info.info_len)) 3995 return -EFAULT; 3996 3997 return 0; 3998 } 3999 4000 4001 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 4002 4003 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 4004 union bpf_attr __user *uattr) 4005 { 4006 int ufd = attr->info.bpf_fd; 4007 struct fd f; 4008 int err; 4009 4010 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4011 return -EINVAL; 4012 4013 f = fdget(ufd); 4014 if (!f.file) 4015 return -EBADFD; 4016 4017 if (f.file->f_op == &bpf_prog_fops) 4018 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr, 4019 uattr); 4020 else if (f.file->f_op == &bpf_map_fops) 4021 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr, 4022 uattr); 4023 else if (f.file->f_op == &btf_fops) 4024 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr); 4025 else if (f.file->f_op == &bpf_link_fops) 4026 err = bpf_link_get_info_by_fd(f.file, f.file->private_data, 4027 attr, uattr); 4028 else 4029 err = -EINVAL; 4030 4031 fdput(f); 4032 return err; 4033 } 4034 4035 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 4036 4037 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr) 4038 { 4039 if (CHECK_ATTR(BPF_BTF_LOAD)) 4040 return -EINVAL; 4041 4042 if (!bpf_capable()) 4043 return -EPERM; 4044 4045 return btf_new_fd(attr, uattr); 4046 } 4047 4048 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4049 4050 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4051 { 4052 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4053 return -EINVAL; 4054 4055 if (!capable(CAP_SYS_ADMIN)) 4056 return -EPERM; 4057 4058 return btf_get_fd_by_id(attr->btf_id); 4059 } 4060 4061 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 4062 union bpf_attr __user *uattr, 4063 u32 prog_id, u32 fd_type, 4064 const char *buf, u64 probe_offset, 4065 u64 probe_addr) 4066 { 4067 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 4068 u32 len = buf ? strlen(buf) : 0, input_len; 4069 int err = 0; 4070 4071 if (put_user(len, &uattr->task_fd_query.buf_len)) 4072 return -EFAULT; 4073 input_len = attr->task_fd_query.buf_len; 4074 if (input_len && ubuf) { 4075 if (!len) { 4076 /* nothing to copy, just make ubuf NULL terminated */ 4077 char zero = '\0'; 4078 4079 if (put_user(zero, ubuf)) 4080 return -EFAULT; 4081 } else if (input_len >= len + 1) { 4082 /* ubuf can hold the string with NULL terminator */ 4083 if (copy_to_user(ubuf, buf, len + 1)) 4084 return -EFAULT; 4085 } else { 4086 /* ubuf cannot hold the string with NULL terminator, 4087 * do a partial copy with NULL terminator. 4088 */ 4089 char zero = '\0'; 4090 4091 err = -ENOSPC; 4092 if (copy_to_user(ubuf, buf, input_len - 1)) 4093 return -EFAULT; 4094 if (put_user(zero, ubuf + input_len - 1)) 4095 return -EFAULT; 4096 } 4097 } 4098 4099 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 4100 put_user(fd_type, &uattr->task_fd_query.fd_type) || 4101 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 4102 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 4103 return -EFAULT; 4104 4105 return err; 4106 } 4107 4108 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 4109 4110 static int bpf_task_fd_query(const union bpf_attr *attr, 4111 union bpf_attr __user *uattr) 4112 { 4113 pid_t pid = attr->task_fd_query.pid; 4114 u32 fd = attr->task_fd_query.fd; 4115 const struct perf_event *event; 4116 struct task_struct *task; 4117 struct file *file; 4118 int err; 4119 4120 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 4121 return -EINVAL; 4122 4123 if (!capable(CAP_SYS_ADMIN)) 4124 return -EPERM; 4125 4126 if (attr->task_fd_query.flags != 0) 4127 return -EINVAL; 4128 4129 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 4130 if (!task) 4131 return -ENOENT; 4132 4133 err = 0; 4134 file = fget_task(task, fd); 4135 put_task_struct(task); 4136 if (!file) 4137 return -EBADF; 4138 4139 if (file->f_op == &bpf_link_fops) { 4140 struct bpf_link *link = file->private_data; 4141 4142 if (link->ops == &bpf_raw_tp_link_lops) { 4143 struct bpf_raw_tp_link *raw_tp = 4144 container_of(link, struct bpf_raw_tp_link, link); 4145 struct bpf_raw_event_map *btp = raw_tp->btp; 4146 4147 err = bpf_task_fd_query_copy(attr, uattr, 4148 raw_tp->link.prog->aux->id, 4149 BPF_FD_TYPE_RAW_TRACEPOINT, 4150 btp->tp->name, 0, 0); 4151 goto put_file; 4152 } 4153 goto out_not_supp; 4154 } 4155 4156 event = perf_get_event(file); 4157 if (!IS_ERR(event)) { 4158 u64 probe_offset, probe_addr; 4159 u32 prog_id, fd_type; 4160 const char *buf; 4161 4162 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 4163 &buf, &probe_offset, 4164 &probe_addr); 4165 if (!err) 4166 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 4167 fd_type, buf, 4168 probe_offset, 4169 probe_addr); 4170 goto put_file; 4171 } 4172 4173 out_not_supp: 4174 err = -ENOTSUPP; 4175 put_file: 4176 fput(file); 4177 return err; 4178 } 4179 4180 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 4181 4182 #define BPF_DO_BATCH(fn) \ 4183 do { \ 4184 if (!fn) { \ 4185 err = -ENOTSUPP; \ 4186 goto err_put; \ 4187 } \ 4188 err = fn(map, attr, uattr); \ 4189 } while (0) 4190 4191 static int bpf_map_do_batch(const union bpf_attr *attr, 4192 union bpf_attr __user *uattr, 4193 int cmd) 4194 { 4195 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 4196 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 4197 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 4198 struct bpf_map *map; 4199 int err, ufd; 4200 struct fd f; 4201 4202 if (CHECK_ATTR(BPF_MAP_BATCH)) 4203 return -EINVAL; 4204 4205 ufd = attr->batch.map_fd; 4206 f = fdget(ufd); 4207 map = __bpf_map_get(f); 4208 if (IS_ERR(map)) 4209 return PTR_ERR(map); 4210 if (has_write) 4211 bpf_map_write_active_inc(map); 4212 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 4213 err = -EPERM; 4214 goto err_put; 4215 } 4216 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 4217 err = -EPERM; 4218 goto err_put; 4219 } 4220 4221 if (cmd == BPF_MAP_LOOKUP_BATCH) 4222 BPF_DO_BATCH(map->ops->map_lookup_batch); 4223 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 4224 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 4225 else if (cmd == BPF_MAP_UPDATE_BATCH) 4226 BPF_DO_BATCH(map->ops->map_update_batch); 4227 else 4228 BPF_DO_BATCH(map->ops->map_delete_batch); 4229 err_put: 4230 if (has_write) 4231 bpf_map_write_active_dec(map); 4232 fdput(f); 4233 return err; 4234 } 4235 4236 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, 4237 struct bpf_prog *prog) 4238 { 4239 if (attr->link_create.attach_type != prog->expected_attach_type) 4240 return -EINVAL; 4241 4242 if (prog->expected_attach_type == BPF_TRACE_ITER) 4243 return bpf_iter_link_attach(attr, uattr, prog); 4244 else if (prog->type == BPF_PROG_TYPE_EXT) 4245 return bpf_tracing_prog_attach(prog, 4246 attr->link_create.target_fd, 4247 attr->link_create.target_btf_id); 4248 return -EINVAL; 4249 } 4250 4251 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len 4252 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 4253 { 4254 enum bpf_prog_type ptype; 4255 struct bpf_prog *prog; 4256 int ret; 4257 4258 if (CHECK_ATTR(BPF_LINK_CREATE)) 4259 return -EINVAL; 4260 4261 prog = bpf_prog_get(attr->link_create.prog_fd); 4262 if (IS_ERR(prog)) 4263 return PTR_ERR(prog); 4264 4265 ret = bpf_prog_attach_check_attach_type(prog, 4266 attr->link_create.attach_type); 4267 if (ret) 4268 goto out; 4269 4270 switch (prog->type) { 4271 case BPF_PROG_TYPE_EXT: 4272 ret = tracing_bpf_link_attach(attr, uattr, prog); 4273 goto out; 4274 case BPF_PROG_TYPE_PERF_EVENT: 4275 case BPF_PROG_TYPE_KPROBE: 4276 case BPF_PROG_TYPE_TRACEPOINT: 4277 if (attr->link_create.attach_type != BPF_PERF_EVENT) { 4278 ret = -EINVAL; 4279 goto out; 4280 } 4281 ptype = prog->type; 4282 break; 4283 default: 4284 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 4285 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) { 4286 ret = -EINVAL; 4287 goto out; 4288 } 4289 break; 4290 } 4291 4292 switch (ptype) { 4293 case BPF_PROG_TYPE_CGROUP_SKB: 4294 case BPF_PROG_TYPE_CGROUP_SOCK: 4295 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4296 case BPF_PROG_TYPE_SOCK_OPS: 4297 case BPF_PROG_TYPE_CGROUP_DEVICE: 4298 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4299 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4300 ret = cgroup_bpf_link_attach(attr, prog); 4301 break; 4302 case BPF_PROG_TYPE_TRACING: 4303 ret = tracing_bpf_link_attach(attr, uattr, prog); 4304 break; 4305 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4306 case BPF_PROG_TYPE_SK_LOOKUP: 4307 ret = netns_bpf_link_create(attr, prog); 4308 break; 4309 #ifdef CONFIG_NET 4310 case BPF_PROG_TYPE_XDP: 4311 ret = bpf_xdp_link_attach(attr, prog); 4312 break; 4313 #endif 4314 #ifdef CONFIG_PERF_EVENTS 4315 case BPF_PROG_TYPE_PERF_EVENT: 4316 case BPF_PROG_TYPE_TRACEPOINT: 4317 case BPF_PROG_TYPE_KPROBE: 4318 ret = bpf_perf_link_attach(attr, prog); 4319 break; 4320 #endif 4321 default: 4322 ret = -EINVAL; 4323 } 4324 4325 out: 4326 if (ret < 0) 4327 bpf_prog_put(prog); 4328 return ret; 4329 } 4330 4331 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 4332 4333 static int link_update(union bpf_attr *attr) 4334 { 4335 struct bpf_prog *old_prog = NULL, *new_prog; 4336 struct bpf_link *link; 4337 u32 flags; 4338 int ret; 4339 4340 if (CHECK_ATTR(BPF_LINK_UPDATE)) 4341 return -EINVAL; 4342 4343 flags = attr->link_update.flags; 4344 if (flags & ~BPF_F_REPLACE) 4345 return -EINVAL; 4346 4347 link = bpf_link_get_from_fd(attr->link_update.link_fd); 4348 if (IS_ERR(link)) 4349 return PTR_ERR(link); 4350 4351 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 4352 if (IS_ERR(new_prog)) { 4353 ret = PTR_ERR(new_prog); 4354 goto out_put_link; 4355 } 4356 4357 if (flags & BPF_F_REPLACE) { 4358 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 4359 if (IS_ERR(old_prog)) { 4360 ret = PTR_ERR(old_prog); 4361 old_prog = NULL; 4362 goto out_put_progs; 4363 } 4364 } else if (attr->link_update.old_prog_fd) { 4365 ret = -EINVAL; 4366 goto out_put_progs; 4367 } 4368 4369 if (link->ops->update_prog) 4370 ret = link->ops->update_prog(link, new_prog, old_prog); 4371 else 4372 ret = -EINVAL; 4373 4374 out_put_progs: 4375 if (old_prog) 4376 bpf_prog_put(old_prog); 4377 if (ret) 4378 bpf_prog_put(new_prog); 4379 out_put_link: 4380 bpf_link_put(link); 4381 return ret; 4382 } 4383 4384 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 4385 4386 static int link_detach(union bpf_attr *attr) 4387 { 4388 struct bpf_link *link; 4389 int ret; 4390 4391 if (CHECK_ATTR(BPF_LINK_DETACH)) 4392 return -EINVAL; 4393 4394 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 4395 if (IS_ERR(link)) 4396 return PTR_ERR(link); 4397 4398 if (link->ops->detach) 4399 ret = link->ops->detach(link); 4400 else 4401 ret = -EOPNOTSUPP; 4402 4403 bpf_link_put(link); 4404 return ret; 4405 } 4406 4407 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 4408 { 4409 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 4410 } 4411 4412 struct bpf_link *bpf_link_by_id(u32 id) 4413 { 4414 struct bpf_link *link; 4415 4416 if (!id) 4417 return ERR_PTR(-ENOENT); 4418 4419 spin_lock_bh(&link_idr_lock); 4420 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 4421 link = idr_find(&link_idr, id); 4422 if (link) { 4423 if (link->id) 4424 link = bpf_link_inc_not_zero(link); 4425 else 4426 link = ERR_PTR(-EAGAIN); 4427 } else { 4428 link = ERR_PTR(-ENOENT); 4429 } 4430 spin_unlock_bh(&link_idr_lock); 4431 return link; 4432 } 4433 4434 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 4435 4436 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 4437 { 4438 struct bpf_link *link; 4439 u32 id = attr->link_id; 4440 int fd; 4441 4442 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 4443 return -EINVAL; 4444 4445 if (!capable(CAP_SYS_ADMIN)) 4446 return -EPERM; 4447 4448 link = bpf_link_by_id(id); 4449 if (IS_ERR(link)) 4450 return PTR_ERR(link); 4451 4452 fd = bpf_link_new_fd(link); 4453 if (fd < 0) 4454 bpf_link_put(link); 4455 4456 return fd; 4457 } 4458 4459 DEFINE_MUTEX(bpf_stats_enabled_mutex); 4460 4461 static int bpf_stats_release(struct inode *inode, struct file *file) 4462 { 4463 mutex_lock(&bpf_stats_enabled_mutex); 4464 static_key_slow_dec(&bpf_stats_enabled_key.key); 4465 mutex_unlock(&bpf_stats_enabled_mutex); 4466 return 0; 4467 } 4468 4469 static const struct file_operations bpf_stats_fops = { 4470 .release = bpf_stats_release, 4471 }; 4472 4473 static int bpf_enable_runtime_stats(void) 4474 { 4475 int fd; 4476 4477 mutex_lock(&bpf_stats_enabled_mutex); 4478 4479 /* Set a very high limit to avoid overflow */ 4480 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 4481 mutex_unlock(&bpf_stats_enabled_mutex); 4482 return -EBUSY; 4483 } 4484 4485 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 4486 if (fd >= 0) 4487 static_key_slow_inc(&bpf_stats_enabled_key.key); 4488 4489 mutex_unlock(&bpf_stats_enabled_mutex); 4490 return fd; 4491 } 4492 4493 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 4494 4495 static int bpf_enable_stats(union bpf_attr *attr) 4496 { 4497 4498 if (CHECK_ATTR(BPF_ENABLE_STATS)) 4499 return -EINVAL; 4500 4501 if (!capable(CAP_SYS_ADMIN)) 4502 return -EPERM; 4503 4504 switch (attr->enable_stats.type) { 4505 case BPF_STATS_RUN_TIME: 4506 return bpf_enable_runtime_stats(); 4507 default: 4508 break; 4509 } 4510 return -EINVAL; 4511 } 4512 4513 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 4514 4515 static int bpf_iter_create(union bpf_attr *attr) 4516 { 4517 struct bpf_link *link; 4518 int err; 4519 4520 if (CHECK_ATTR(BPF_ITER_CREATE)) 4521 return -EINVAL; 4522 4523 if (attr->iter_create.flags) 4524 return -EINVAL; 4525 4526 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 4527 if (IS_ERR(link)) 4528 return PTR_ERR(link); 4529 4530 err = bpf_iter_new_fd(link); 4531 bpf_link_put(link); 4532 4533 return err; 4534 } 4535 4536 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 4537 4538 static int bpf_prog_bind_map(union bpf_attr *attr) 4539 { 4540 struct bpf_prog *prog; 4541 struct bpf_map *map; 4542 struct bpf_map **used_maps_old, **used_maps_new; 4543 int i, ret = 0; 4544 4545 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 4546 return -EINVAL; 4547 4548 if (attr->prog_bind_map.flags) 4549 return -EINVAL; 4550 4551 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 4552 if (IS_ERR(prog)) 4553 return PTR_ERR(prog); 4554 4555 map = bpf_map_get(attr->prog_bind_map.map_fd); 4556 if (IS_ERR(map)) { 4557 ret = PTR_ERR(map); 4558 goto out_prog_put; 4559 } 4560 4561 mutex_lock(&prog->aux->used_maps_mutex); 4562 4563 used_maps_old = prog->aux->used_maps; 4564 4565 for (i = 0; i < prog->aux->used_map_cnt; i++) 4566 if (used_maps_old[i] == map) { 4567 bpf_map_put(map); 4568 goto out_unlock; 4569 } 4570 4571 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 4572 sizeof(used_maps_new[0]), 4573 GFP_KERNEL); 4574 if (!used_maps_new) { 4575 ret = -ENOMEM; 4576 goto out_unlock; 4577 } 4578 4579 memcpy(used_maps_new, used_maps_old, 4580 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 4581 used_maps_new[prog->aux->used_map_cnt] = map; 4582 4583 prog->aux->used_map_cnt++; 4584 prog->aux->used_maps = used_maps_new; 4585 4586 kfree(used_maps_old); 4587 4588 out_unlock: 4589 mutex_unlock(&prog->aux->used_maps_mutex); 4590 4591 if (ret) 4592 bpf_map_put(map); 4593 out_prog_put: 4594 bpf_prog_put(prog); 4595 return ret; 4596 } 4597 4598 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) 4599 { 4600 union bpf_attr attr; 4601 int err; 4602 4603 if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) 4604 return -EPERM; 4605 4606 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 4607 if (err) 4608 return err; 4609 size = min_t(u32, size, sizeof(attr)); 4610 4611 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 4612 memset(&attr, 0, sizeof(attr)); 4613 if (copy_from_bpfptr(&attr, uattr, size) != 0) 4614 return -EFAULT; 4615 4616 err = security_bpf(cmd, &attr, size); 4617 if (err < 0) 4618 return err; 4619 4620 switch (cmd) { 4621 case BPF_MAP_CREATE: 4622 err = map_create(&attr); 4623 break; 4624 case BPF_MAP_LOOKUP_ELEM: 4625 err = map_lookup_elem(&attr); 4626 break; 4627 case BPF_MAP_UPDATE_ELEM: 4628 err = map_update_elem(&attr, uattr); 4629 break; 4630 case BPF_MAP_DELETE_ELEM: 4631 err = map_delete_elem(&attr); 4632 break; 4633 case BPF_MAP_GET_NEXT_KEY: 4634 err = map_get_next_key(&attr); 4635 break; 4636 case BPF_MAP_FREEZE: 4637 err = map_freeze(&attr); 4638 break; 4639 case BPF_PROG_LOAD: 4640 err = bpf_prog_load(&attr, uattr); 4641 break; 4642 case BPF_OBJ_PIN: 4643 err = bpf_obj_pin(&attr); 4644 break; 4645 case BPF_OBJ_GET: 4646 err = bpf_obj_get(&attr); 4647 break; 4648 case BPF_PROG_ATTACH: 4649 err = bpf_prog_attach(&attr); 4650 break; 4651 case BPF_PROG_DETACH: 4652 err = bpf_prog_detach(&attr); 4653 break; 4654 case BPF_PROG_QUERY: 4655 err = bpf_prog_query(&attr, uattr.user); 4656 break; 4657 case BPF_PROG_TEST_RUN: 4658 err = bpf_prog_test_run(&attr, uattr.user); 4659 break; 4660 case BPF_PROG_GET_NEXT_ID: 4661 err = bpf_obj_get_next_id(&attr, uattr.user, 4662 &prog_idr, &prog_idr_lock); 4663 break; 4664 case BPF_MAP_GET_NEXT_ID: 4665 err = bpf_obj_get_next_id(&attr, uattr.user, 4666 &map_idr, &map_idr_lock); 4667 break; 4668 case BPF_BTF_GET_NEXT_ID: 4669 err = bpf_obj_get_next_id(&attr, uattr.user, 4670 &btf_idr, &btf_idr_lock); 4671 break; 4672 case BPF_PROG_GET_FD_BY_ID: 4673 err = bpf_prog_get_fd_by_id(&attr); 4674 break; 4675 case BPF_MAP_GET_FD_BY_ID: 4676 err = bpf_map_get_fd_by_id(&attr); 4677 break; 4678 case BPF_OBJ_GET_INFO_BY_FD: 4679 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 4680 break; 4681 case BPF_RAW_TRACEPOINT_OPEN: 4682 err = bpf_raw_tracepoint_open(&attr); 4683 break; 4684 case BPF_BTF_LOAD: 4685 err = bpf_btf_load(&attr, uattr); 4686 break; 4687 case BPF_BTF_GET_FD_BY_ID: 4688 err = bpf_btf_get_fd_by_id(&attr); 4689 break; 4690 case BPF_TASK_FD_QUERY: 4691 err = bpf_task_fd_query(&attr, uattr.user); 4692 break; 4693 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 4694 err = map_lookup_and_delete_elem(&attr); 4695 break; 4696 case BPF_MAP_LOOKUP_BATCH: 4697 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 4698 break; 4699 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 4700 err = bpf_map_do_batch(&attr, uattr.user, 4701 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 4702 break; 4703 case BPF_MAP_UPDATE_BATCH: 4704 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 4705 break; 4706 case BPF_MAP_DELETE_BATCH: 4707 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 4708 break; 4709 case BPF_LINK_CREATE: 4710 err = link_create(&attr, uattr); 4711 break; 4712 case BPF_LINK_UPDATE: 4713 err = link_update(&attr); 4714 break; 4715 case BPF_LINK_GET_FD_BY_ID: 4716 err = bpf_link_get_fd_by_id(&attr); 4717 break; 4718 case BPF_LINK_GET_NEXT_ID: 4719 err = bpf_obj_get_next_id(&attr, uattr.user, 4720 &link_idr, &link_idr_lock); 4721 break; 4722 case BPF_ENABLE_STATS: 4723 err = bpf_enable_stats(&attr); 4724 break; 4725 case BPF_ITER_CREATE: 4726 err = bpf_iter_create(&attr); 4727 break; 4728 case BPF_LINK_DETACH: 4729 err = link_detach(&attr); 4730 break; 4731 case BPF_PROG_BIND_MAP: 4732 err = bpf_prog_bind_map(&attr); 4733 break; 4734 default: 4735 err = -EINVAL; 4736 break; 4737 } 4738 4739 return err; 4740 } 4741 4742 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 4743 { 4744 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 4745 } 4746 4747 static bool syscall_prog_is_valid_access(int off, int size, 4748 enum bpf_access_type type, 4749 const struct bpf_prog *prog, 4750 struct bpf_insn_access_aux *info) 4751 { 4752 if (off < 0 || off >= U16_MAX) 4753 return false; 4754 if (off % size != 0) 4755 return false; 4756 return true; 4757 } 4758 4759 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size) 4760 { 4761 switch (cmd) { 4762 case BPF_MAP_CREATE: 4763 case BPF_MAP_UPDATE_ELEM: 4764 case BPF_MAP_FREEZE: 4765 case BPF_PROG_LOAD: 4766 case BPF_BTF_LOAD: 4767 break; 4768 /* case BPF_PROG_TEST_RUN: 4769 * is not part of this list to prevent recursive test_run 4770 */ 4771 default: 4772 return -EINVAL; 4773 } 4774 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 4775 } 4776 4777 static const struct bpf_func_proto bpf_sys_bpf_proto = { 4778 .func = bpf_sys_bpf, 4779 .gpl_only = false, 4780 .ret_type = RET_INTEGER, 4781 .arg1_type = ARG_ANYTHING, 4782 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 4783 .arg3_type = ARG_CONST_SIZE, 4784 }; 4785 4786 const struct bpf_func_proto * __weak 4787 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4788 { 4789 return bpf_base_func_proto(func_id); 4790 } 4791 4792 BPF_CALL_1(bpf_sys_close, u32, fd) 4793 { 4794 /* When bpf program calls this helper there should not be 4795 * an fdget() without matching completed fdput(). 4796 * This helper is allowed in the following callchain only: 4797 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 4798 */ 4799 return close_fd(fd); 4800 } 4801 4802 static const struct bpf_func_proto bpf_sys_close_proto = { 4803 .func = bpf_sys_close, 4804 .gpl_only = false, 4805 .ret_type = RET_INTEGER, 4806 .arg1_type = ARG_ANYTHING, 4807 }; 4808 4809 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 4810 { 4811 if (flags) 4812 return -EINVAL; 4813 4814 if (name_sz <= 1 || name[name_sz - 1]) 4815 return -EINVAL; 4816 4817 if (!bpf_dump_raw_ok(current_cred())) 4818 return -EPERM; 4819 4820 *res = kallsyms_lookup_name(name); 4821 return *res ? 0 : -ENOENT; 4822 } 4823 4824 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 4825 .func = bpf_kallsyms_lookup_name, 4826 .gpl_only = false, 4827 .ret_type = RET_INTEGER, 4828 .arg1_type = ARG_PTR_TO_MEM, 4829 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 4830 .arg3_type = ARG_ANYTHING, 4831 .arg4_type = ARG_PTR_TO_LONG, 4832 }; 4833 4834 static const struct bpf_func_proto * 4835 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4836 { 4837 switch (func_id) { 4838 case BPF_FUNC_sys_bpf: 4839 return &bpf_sys_bpf_proto; 4840 case BPF_FUNC_btf_find_by_name_kind: 4841 return &bpf_btf_find_by_name_kind_proto; 4842 case BPF_FUNC_sys_close: 4843 return &bpf_sys_close_proto; 4844 case BPF_FUNC_kallsyms_lookup_name: 4845 return &bpf_kallsyms_lookup_name_proto; 4846 default: 4847 return tracing_prog_func_proto(func_id, prog); 4848 } 4849 } 4850 4851 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 4852 .get_func_proto = syscall_prog_func_proto, 4853 .is_valid_access = syscall_prog_is_valid_access, 4854 }; 4855 4856 const struct bpf_prog_ops bpf_syscall_prog_ops = { 4857 .test_run = bpf_prog_test_run_syscall, 4858 }; 4859