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 EXPORT_SYMBOL(bpf_map_get); 989 990 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 991 { 992 struct fd f = fdget(ufd); 993 struct bpf_map *map; 994 995 map = __bpf_map_get(f); 996 if (IS_ERR(map)) 997 return map; 998 999 bpf_map_inc_with_uref(map); 1000 fdput(f); 1001 1002 return map; 1003 } 1004 1005 /* map_idr_lock should have been held */ 1006 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1007 { 1008 int refold; 1009 1010 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1011 if (!refold) 1012 return ERR_PTR(-ENOENT); 1013 if (uref) 1014 atomic64_inc(&map->usercnt); 1015 1016 return map; 1017 } 1018 1019 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1020 { 1021 spin_lock_bh(&map_idr_lock); 1022 map = __bpf_map_inc_not_zero(map, false); 1023 spin_unlock_bh(&map_idr_lock); 1024 1025 return map; 1026 } 1027 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1028 1029 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1030 { 1031 return -ENOTSUPP; 1032 } 1033 1034 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1035 { 1036 if (key_size) 1037 return vmemdup_user(ukey, key_size); 1038 1039 if (ukey) 1040 return ERR_PTR(-EINVAL); 1041 1042 return NULL; 1043 } 1044 1045 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1046 { 1047 if (key_size) 1048 return kvmemdup_bpfptr(ukey, key_size); 1049 1050 if (!bpfptr_is_null(ukey)) 1051 return ERR_PTR(-EINVAL); 1052 1053 return NULL; 1054 } 1055 1056 /* last field in 'union bpf_attr' used by this command */ 1057 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1058 1059 static int map_lookup_elem(union bpf_attr *attr) 1060 { 1061 void __user *ukey = u64_to_user_ptr(attr->key); 1062 void __user *uvalue = u64_to_user_ptr(attr->value); 1063 int ufd = attr->map_fd; 1064 struct bpf_map *map; 1065 void *key, *value; 1066 u32 value_size; 1067 struct fd f; 1068 int err; 1069 1070 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1071 return -EINVAL; 1072 1073 if (attr->flags & ~BPF_F_LOCK) 1074 return -EINVAL; 1075 1076 f = fdget(ufd); 1077 map = __bpf_map_get(f); 1078 if (IS_ERR(map)) 1079 return PTR_ERR(map); 1080 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1081 err = -EPERM; 1082 goto err_put; 1083 } 1084 1085 if ((attr->flags & BPF_F_LOCK) && 1086 !map_value_has_spin_lock(map)) { 1087 err = -EINVAL; 1088 goto err_put; 1089 } 1090 1091 key = __bpf_copy_key(ukey, map->key_size); 1092 if (IS_ERR(key)) { 1093 err = PTR_ERR(key); 1094 goto err_put; 1095 } 1096 1097 value_size = bpf_map_value_size(map); 1098 1099 err = -ENOMEM; 1100 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1101 if (!value) 1102 goto free_key; 1103 1104 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1105 if (copy_from_user(value, uvalue, value_size)) 1106 err = -EFAULT; 1107 else 1108 err = bpf_map_copy_value(map, key, value, attr->flags); 1109 goto free_value; 1110 } 1111 1112 err = bpf_map_copy_value(map, key, value, attr->flags); 1113 if (err) 1114 goto free_value; 1115 1116 err = -EFAULT; 1117 if (copy_to_user(uvalue, value, value_size) != 0) 1118 goto free_value; 1119 1120 err = 0; 1121 1122 free_value: 1123 kvfree(value); 1124 free_key: 1125 kvfree(key); 1126 err_put: 1127 fdput(f); 1128 return err; 1129 } 1130 1131 1132 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1133 1134 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1135 { 1136 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1137 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1138 int ufd = attr->map_fd; 1139 struct bpf_map *map; 1140 void *key, *value; 1141 u32 value_size; 1142 struct fd f; 1143 int err; 1144 1145 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1146 return -EINVAL; 1147 1148 f = fdget(ufd); 1149 map = __bpf_map_get(f); 1150 if (IS_ERR(map)) 1151 return PTR_ERR(map); 1152 bpf_map_write_active_inc(map); 1153 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1154 err = -EPERM; 1155 goto err_put; 1156 } 1157 1158 if ((attr->flags & BPF_F_LOCK) && 1159 !map_value_has_spin_lock(map)) { 1160 err = -EINVAL; 1161 goto err_put; 1162 } 1163 1164 key = ___bpf_copy_key(ukey, map->key_size); 1165 if (IS_ERR(key)) { 1166 err = PTR_ERR(key); 1167 goto err_put; 1168 } 1169 1170 value_size = bpf_map_value_size(map); 1171 1172 err = -ENOMEM; 1173 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1174 if (!value) 1175 goto free_key; 1176 1177 err = -EFAULT; 1178 if (copy_from_bpfptr(value, uvalue, value_size) != 0) 1179 goto free_value; 1180 1181 err = bpf_map_update_value(map, f, key, value, attr->flags); 1182 1183 free_value: 1184 kvfree(value); 1185 free_key: 1186 kvfree(key); 1187 err_put: 1188 bpf_map_write_active_dec(map); 1189 fdput(f); 1190 return err; 1191 } 1192 1193 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1194 1195 static int map_delete_elem(union bpf_attr *attr) 1196 { 1197 void __user *ukey = u64_to_user_ptr(attr->key); 1198 int ufd = attr->map_fd; 1199 struct bpf_map *map; 1200 struct fd f; 1201 void *key; 1202 int err; 1203 1204 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1205 return -EINVAL; 1206 1207 f = fdget(ufd); 1208 map = __bpf_map_get(f); 1209 if (IS_ERR(map)) 1210 return PTR_ERR(map); 1211 bpf_map_write_active_inc(map); 1212 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1213 err = -EPERM; 1214 goto err_put; 1215 } 1216 1217 key = __bpf_copy_key(ukey, map->key_size); 1218 if (IS_ERR(key)) { 1219 err = PTR_ERR(key); 1220 goto err_put; 1221 } 1222 1223 if (bpf_map_is_dev_bound(map)) { 1224 err = bpf_map_offload_delete_elem(map, key); 1225 goto out; 1226 } else if (IS_FD_PROG_ARRAY(map) || 1227 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1228 /* These maps require sleepable context */ 1229 err = map->ops->map_delete_elem(map, key); 1230 goto out; 1231 } 1232 1233 bpf_disable_instrumentation(); 1234 rcu_read_lock(); 1235 err = map->ops->map_delete_elem(map, key); 1236 rcu_read_unlock(); 1237 bpf_enable_instrumentation(); 1238 maybe_wait_bpf_programs(map); 1239 out: 1240 kvfree(key); 1241 err_put: 1242 bpf_map_write_active_dec(map); 1243 fdput(f); 1244 return err; 1245 } 1246 1247 /* last field in 'union bpf_attr' used by this command */ 1248 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1249 1250 static int map_get_next_key(union bpf_attr *attr) 1251 { 1252 void __user *ukey = u64_to_user_ptr(attr->key); 1253 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1254 int ufd = attr->map_fd; 1255 struct bpf_map *map; 1256 void *key, *next_key; 1257 struct fd f; 1258 int err; 1259 1260 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1261 return -EINVAL; 1262 1263 f = fdget(ufd); 1264 map = __bpf_map_get(f); 1265 if (IS_ERR(map)) 1266 return PTR_ERR(map); 1267 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1268 err = -EPERM; 1269 goto err_put; 1270 } 1271 1272 if (ukey) { 1273 key = __bpf_copy_key(ukey, map->key_size); 1274 if (IS_ERR(key)) { 1275 err = PTR_ERR(key); 1276 goto err_put; 1277 } 1278 } else { 1279 key = NULL; 1280 } 1281 1282 err = -ENOMEM; 1283 next_key = kvmalloc(map->key_size, GFP_USER); 1284 if (!next_key) 1285 goto free_key; 1286 1287 if (bpf_map_is_dev_bound(map)) { 1288 err = bpf_map_offload_get_next_key(map, key, next_key); 1289 goto out; 1290 } 1291 1292 rcu_read_lock(); 1293 err = map->ops->map_get_next_key(map, key, next_key); 1294 rcu_read_unlock(); 1295 out: 1296 if (err) 1297 goto free_next_key; 1298 1299 err = -EFAULT; 1300 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1301 goto free_next_key; 1302 1303 err = 0; 1304 1305 free_next_key: 1306 kvfree(next_key); 1307 free_key: 1308 kvfree(key); 1309 err_put: 1310 fdput(f); 1311 return err; 1312 } 1313 1314 int generic_map_delete_batch(struct bpf_map *map, 1315 const union bpf_attr *attr, 1316 union bpf_attr __user *uattr) 1317 { 1318 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1319 u32 cp, max_count; 1320 int err = 0; 1321 void *key; 1322 1323 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1324 return -EINVAL; 1325 1326 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1327 !map_value_has_spin_lock(map)) { 1328 return -EINVAL; 1329 } 1330 1331 max_count = attr->batch.count; 1332 if (!max_count) 1333 return 0; 1334 1335 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1336 if (!key) 1337 return -ENOMEM; 1338 1339 for (cp = 0; cp < max_count; cp++) { 1340 err = -EFAULT; 1341 if (copy_from_user(key, keys + cp * map->key_size, 1342 map->key_size)) 1343 break; 1344 1345 if (bpf_map_is_dev_bound(map)) { 1346 err = bpf_map_offload_delete_elem(map, key); 1347 break; 1348 } 1349 1350 bpf_disable_instrumentation(); 1351 rcu_read_lock(); 1352 err = map->ops->map_delete_elem(map, key); 1353 rcu_read_unlock(); 1354 bpf_enable_instrumentation(); 1355 maybe_wait_bpf_programs(map); 1356 if (err) 1357 break; 1358 } 1359 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1360 err = -EFAULT; 1361 1362 kvfree(key); 1363 return err; 1364 } 1365 1366 int generic_map_update_batch(struct bpf_map *map, 1367 const union bpf_attr *attr, 1368 union bpf_attr __user *uattr) 1369 { 1370 void __user *values = u64_to_user_ptr(attr->batch.values); 1371 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1372 u32 value_size, cp, max_count; 1373 int ufd = attr->batch.map_fd; 1374 void *key, *value; 1375 struct fd f; 1376 int err = 0; 1377 1378 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1379 return -EINVAL; 1380 1381 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1382 !map_value_has_spin_lock(map)) { 1383 return -EINVAL; 1384 } 1385 1386 value_size = bpf_map_value_size(map); 1387 1388 max_count = attr->batch.count; 1389 if (!max_count) 1390 return 0; 1391 1392 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1393 if (!key) 1394 return -ENOMEM; 1395 1396 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1397 if (!value) { 1398 kvfree(key); 1399 return -ENOMEM; 1400 } 1401 1402 f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */ 1403 for (cp = 0; cp < max_count; cp++) { 1404 err = -EFAULT; 1405 if (copy_from_user(key, keys + cp * map->key_size, 1406 map->key_size) || 1407 copy_from_user(value, values + cp * value_size, value_size)) 1408 break; 1409 1410 err = bpf_map_update_value(map, f, key, value, 1411 attr->batch.elem_flags); 1412 1413 if (err) 1414 break; 1415 } 1416 1417 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1418 err = -EFAULT; 1419 1420 kvfree(value); 1421 kvfree(key); 1422 fdput(f); 1423 return err; 1424 } 1425 1426 #define MAP_LOOKUP_RETRIES 3 1427 1428 int generic_map_lookup_batch(struct bpf_map *map, 1429 const union bpf_attr *attr, 1430 union bpf_attr __user *uattr) 1431 { 1432 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1433 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1434 void __user *values = u64_to_user_ptr(attr->batch.values); 1435 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1436 void *buf, *buf_prevkey, *prev_key, *key, *value; 1437 int err, retry = MAP_LOOKUP_RETRIES; 1438 u32 value_size, cp, max_count; 1439 1440 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1441 return -EINVAL; 1442 1443 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1444 !map_value_has_spin_lock(map)) 1445 return -EINVAL; 1446 1447 value_size = bpf_map_value_size(map); 1448 1449 max_count = attr->batch.count; 1450 if (!max_count) 1451 return 0; 1452 1453 if (put_user(0, &uattr->batch.count)) 1454 return -EFAULT; 1455 1456 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1457 if (!buf_prevkey) 1458 return -ENOMEM; 1459 1460 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1461 if (!buf) { 1462 kvfree(buf_prevkey); 1463 return -ENOMEM; 1464 } 1465 1466 err = -EFAULT; 1467 prev_key = NULL; 1468 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1469 goto free_buf; 1470 key = buf; 1471 value = key + map->key_size; 1472 if (ubatch) 1473 prev_key = buf_prevkey; 1474 1475 for (cp = 0; cp < max_count;) { 1476 rcu_read_lock(); 1477 err = map->ops->map_get_next_key(map, prev_key, key); 1478 rcu_read_unlock(); 1479 if (err) 1480 break; 1481 err = bpf_map_copy_value(map, key, value, 1482 attr->batch.elem_flags); 1483 1484 if (err == -ENOENT) { 1485 if (retry) { 1486 retry--; 1487 continue; 1488 } 1489 err = -EINTR; 1490 break; 1491 } 1492 1493 if (err) 1494 goto free_buf; 1495 1496 if (copy_to_user(keys + cp * map->key_size, key, 1497 map->key_size)) { 1498 err = -EFAULT; 1499 goto free_buf; 1500 } 1501 if (copy_to_user(values + cp * value_size, value, value_size)) { 1502 err = -EFAULT; 1503 goto free_buf; 1504 } 1505 1506 if (!prev_key) 1507 prev_key = buf_prevkey; 1508 1509 swap(prev_key, key); 1510 retry = MAP_LOOKUP_RETRIES; 1511 cp++; 1512 } 1513 1514 if (err == -EFAULT) 1515 goto free_buf; 1516 1517 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1518 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1519 err = -EFAULT; 1520 1521 free_buf: 1522 kvfree(buf_prevkey); 1523 kvfree(buf); 1524 return err; 1525 } 1526 1527 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 1528 1529 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1530 { 1531 void __user *ukey = u64_to_user_ptr(attr->key); 1532 void __user *uvalue = u64_to_user_ptr(attr->value); 1533 int ufd = attr->map_fd; 1534 struct bpf_map *map; 1535 void *key, *value; 1536 u32 value_size; 1537 struct fd f; 1538 int err; 1539 1540 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1541 return -EINVAL; 1542 1543 if (attr->flags & ~BPF_F_LOCK) 1544 return -EINVAL; 1545 1546 f = fdget(ufd); 1547 map = __bpf_map_get(f); 1548 if (IS_ERR(map)) 1549 return PTR_ERR(map); 1550 bpf_map_write_active_inc(map); 1551 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 1552 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1553 err = -EPERM; 1554 goto err_put; 1555 } 1556 1557 if (attr->flags && 1558 (map->map_type == BPF_MAP_TYPE_QUEUE || 1559 map->map_type == BPF_MAP_TYPE_STACK)) { 1560 err = -EINVAL; 1561 goto err_put; 1562 } 1563 1564 if ((attr->flags & BPF_F_LOCK) && 1565 !map_value_has_spin_lock(map)) { 1566 err = -EINVAL; 1567 goto err_put; 1568 } 1569 1570 key = __bpf_copy_key(ukey, map->key_size); 1571 if (IS_ERR(key)) { 1572 err = PTR_ERR(key); 1573 goto err_put; 1574 } 1575 1576 value_size = bpf_map_value_size(map); 1577 1578 err = -ENOMEM; 1579 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1580 if (!value) 1581 goto free_key; 1582 1583 err = -ENOTSUPP; 1584 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1585 map->map_type == BPF_MAP_TYPE_STACK) { 1586 err = map->ops->map_pop_elem(map, value); 1587 } else if (map->map_type == BPF_MAP_TYPE_HASH || 1588 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1589 map->map_type == BPF_MAP_TYPE_LRU_HASH || 1590 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 1591 if (!bpf_map_is_dev_bound(map)) { 1592 bpf_disable_instrumentation(); 1593 rcu_read_lock(); 1594 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 1595 rcu_read_unlock(); 1596 bpf_enable_instrumentation(); 1597 } 1598 } 1599 1600 if (err) 1601 goto free_value; 1602 1603 if (copy_to_user(uvalue, value, value_size) != 0) { 1604 err = -EFAULT; 1605 goto free_value; 1606 } 1607 1608 err = 0; 1609 1610 free_value: 1611 kvfree(value); 1612 free_key: 1613 kvfree(key); 1614 err_put: 1615 bpf_map_write_active_dec(map); 1616 fdput(f); 1617 return err; 1618 } 1619 1620 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1621 1622 static int map_freeze(const union bpf_attr *attr) 1623 { 1624 int err = 0, ufd = attr->map_fd; 1625 struct bpf_map *map; 1626 struct fd f; 1627 1628 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1629 return -EINVAL; 1630 1631 f = fdget(ufd); 1632 map = __bpf_map_get(f); 1633 if (IS_ERR(map)) 1634 return PTR_ERR(map); 1635 1636 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || 1637 map_value_has_timer(map)) { 1638 fdput(f); 1639 return -ENOTSUPP; 1640 } 1641 1642 mutex_lock(&map->freeze_mutex); 1643 if (bpf_map_write_active(map)) { 1644 err = -EBUSY; 1645 goto err_put; 1646 } 1647 if (READ_ONCE(map->frozen)) { 1648 err = -EBUSY; 1649 goto err_put; 1650 } 1651 if (!bpf_capable()) { 1652 err = -EPERM; 1653 goto err_put; 1654 } 1655 1656 WRITE_ONCE(map->frozen, true); 1657 err_put: 1658 mutex_unlock(&map->freeze_mutex); 1659 fdput(f); 1660 return err; 1661 } 1662 1663 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1664 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1665 [_id] = & _name ## _prog_ops, 1666 #define BPF_MAP_TYPE(_id, _ops) 1667 #define BPF_LINK_TYPE(_id, _name) 1668 #include <linux/bpf_types.h> 1669 #undef BPF_PROG_TYPE 1670 #undef BPF_MAP_TYPE 1671 #undef BPF_LINK_TYPE 1672 }; 1673 1674 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1675 { 1676 const struct bpf_prog_ops *ops; 1677 1678 if (type >= ARRAY_SIZE(bpf_prog_types)) 1679 return -EINVAL; 1680 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1681 ops = bpf_prog_types[type]; 1682 if (!ops) 1683 return -EINVAL; 1684 1685 if (!bpf_prog_is_dev_bound(prog->aux)) 1686 prog->aux->ops = ops; 1687 else 1688 prog->aux->ops = &bpf_offload_prog_ops; 1689 prog->type = type; 1690 return 0; 1691 } 1692 1693 enum bpf_audit { 1694 BPF_AUDIT_LOAD, 1695 BPF_AUDIT_UNLOAD, 1696 BPF_AUDIT_MAX, 1697 }; 1698 1699 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1700 [BPF_AUDIT_LOAD] = "LOAD", 1701 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1702 }; 1703 1704 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1705 { 1706 struct audit_context *ctx = NULL; 1707 struct audit_buffer *ab; 1708 1709 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1710 return; 1711 if (audit_enabled == AUDIT_OFF) 1712 return; 1713 if (op == BPF_AUDIT_LOAD) 1714 ctx = audit_context(); 1715 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1716 if (unlikely(!ab)) 1717 return; 1718 audit_log_format(ab, "prog-id=%u op=%s", 1719 prog->aux->id, bpf_audit_str[op]); 1720 audit_log_end(ab); 1721 } 1722 1723 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1724 { 1725 int id; 1726 1727 idr_preload(GFP_KERNEL); 1728 spin_lock_bh(&prog_idr_lock); 1729 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1730 if (id > 0) 1731 prog->aux->id = id; 1732 spin_unlock_bh(&prog_idr_lock); 1733 idr_preload_end(); 1734 1735 /* id is in [1, INT_MAX) */ 1736 if (WARN_ON_ONCE(!id)) 1737 return -ENOSPC; 1738 1739 return id > 0 ? 0 : id; 1740 } 1741 1742 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1743 { 1744 unsigned long flags; 1745 1746 /* cBPF to eBPF migrations are currently not in the idr store. 1747 * Offloaded programs are removed from the store when their device 1748 * disappears - even if someone grabs an fd to them they are unusable, 1749 * simply waiting for refcnt to drop to be freed. 1750 */ 1751 if (!prog->aux->id) 1752 return; 1753 1754 if (do_idr_lock) 1755 spin_lock_irqsave(&prog_idr_lock, flags); 1756 else 1757 __acquire(&prog_idr_lock); 1758 1759 idr_remove(&prog_idr, prog->aux->id); 1760 prog->aux->id = 0; 1761 1762 if (do_idr_lock) 1763 spin_unlock_irqrestore(&prog_idr_lock, flags); 1764 else 1765 __release(&prog_idr_lock); 1766 } 1767 1768 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1769 { 1770 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1771 1772 kvfree(aux->func_info); 1773 kfree(aux->func_info_aux); 1774 free_uid(aux->user); 1775 security_bpf_prog_free(aux); 1776 bpf_prog_free(aux->prog); 1777 } 1778 1779 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1780 { 1781 bpf_prog_kallsyms_del_all(prog); 1782 btf_put(prog->aux->btf); 1783 kvfree(prog->aux->jited_linfo); 1784 kvfree(prog->aux->linfo); 1785 kfree(prog->aux->kfunc_tab); 1786 if (prog->aux->attach_btf) 1787 btf_put(prog->aux->attach_btf); 1788 1789 if (deferred) { 1790 if (prog->aux->sleepable) 1791 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 1792 else 1793 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1794 } else { 1795 __bpf_prog_put_rcu(&prog->aux->rcu); 1796 } 1797 } 1798 1799 static void bpf_prog_put_deferred(struct work_struct *work) 1800 { 1801 struct bpf_prog_aux *aux; 1802 struct bpf_prog *prog; 1803 1804 aux = container_of(work, struct bpf_prog_aux, work); 1805 prog = aux->prog; 1806 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1807 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1808 __bpf_prog_put_noref(prog, true); 1809 } 1810 1811 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1812 { 1813 struct bpf_prog_aux *aux = prog->aux; 1814 1815 if (atomic64_dec_and_test(&aux->refcnt)) { 1816 /* bpf_prog_free_id() must be called first */ 1817 bpf_prog_free_id(prog, do_idr_lock); 1818 1819 if (in_irq() || irqs_disabled()) { 1820 INIT_WORK(&aux->work, bpf_prog_put_deferred); 1821 schedule_work(&aux->work); 1822 } else { 1823 bpf_prog_put_deferred(&aux->work); 1824 } 1825 } 1826 } 1827 1828 void bpf_prog_put(struct bpf_prog *prog) 1829 { 1830 __bpf_prog_put(prog, true); 1831 } 1832 EXPORT_SYMBOL_GPL(bpf_prog_put); 1833 1834 static int bpf_prog_release(struct inode *inode, struct file *filp) 1835 { 1836 struct bpf_prog *prog = filp->private_data; 1837 1838 bpf_prog_put(prog); 1839 return 0; 1840 } 1841 1842 struct bpf_prog_kstats { 1843 u64 nsecs; 1844 u64 cnt; 1845 u64 misses; 1846 }; 1847 1848 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1849 struct bpf_prog_kstats *stats) 1850 { 1851 u64 nsecs = 0, cnt = 0, misses = 0; 1852 int cpu; 1853 1854 for_each_possible_cpu(cpu) { 1855 const struct bpf_prog_stats *st; 1856 unsigned int start; 1857 u64 tnsecs, tcnt, tmisses; 1858 1859 st = per_cpu_ptr(prog->stats, cpu); 1860 do { 1861 start = u64_stats_fetch_begin_irq(&st->syncp); 1862 tnsecs = u64_stats_read(&st->nsecs); 1863 tcnt = u64_stats_read(&st->cnt); 1864 tmisses = u64_stats_read(&st->misses); 1865 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1866 nsecs += tnsecs; 1867 cnt += tcnt; 1868 misses += tmisses; 1869 } 1870 stats->nsecs = nsecs; 1871 stats->cnt = cnt; 1872 stats->misses = misses; 1873 } 1874 1875 #ifdef CONFIG_PROC_FS 1876 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1877 { 1878 const struct bpf_prog *prog = filp->private_data; 1879 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1880 struct bpf_prog_kstats stats; 1881 1882 bpf_prog_get_stats(prog, &stats); 1883 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1884 seq_printf(m, 1885 "prog_type:\t%u\n" 1886 "prog_jited:\t%u\n" 1887 "prog_tag:\t%s\n" 1888 "memlock:\t%llu\n" 1889 "prog_id:\t%u\n" 1890 "run_time_ns:\t%llu\n" 1891 "run_cnt:\t%llu\n" 1892 "recursion_misses:\t%llu\n" 1893 "verified_insns:\t%u\n", 1894 prog->type, 1895 prog->jited, 1896 prog_tag, 1897 prog->pages * 1ULL << PAGE_SHIFT, 1898 prog->aux->id, 1899 stats.nsecs, 1900 stats.cnt, 1901 stats.misses, 1902 prog->aux->verified_insns); 1903 } 1904 #endif 1905 1906 const struct file_operations bpf_prog_fops = { 1907 #ifdef CONFIG_PROC_FS 1908 .show_fdinfo = bpf_prog_show_fdinfo, 1909 #endif 1910 .release = bpf_prog_release, 1911 .read = bpf_dummy_read, 1912 .write = bpf_dummy_write, 1913 }; 1914 1915 int bpf_prog_new_fd(struct bpf_prog *prog) 1916 { 1917 int ret; 1918 1919 ret = security_bpf_prog(prog); 1920 if (ret < 0) 1921 return ret; 1922 1923 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1924 O_RDWR | O_CLOEXEC); 1925 } 1926 1927 static struct bpf_prog *____bpf_prog_get(struct fd f) 1928 { 1929 if (!f.file) 1930 return ERR_PTR(-EBADF); 1931 if (f.file->f_op != &bpf_prog_fops) { 1932 fdput(f); 1933 return ERR_PTR(-EINVAL); 1934 } 1935 1936 return f.file->private_data; 1937 } 1938 1939 void bpf_prog_add(struct bpf_prog *prog, int i) 1940 { 1941 atomic64_add(i, &prog->aux->refcnt); 1942 } 1943 EXPORT_SYMBOL_GPL(bpf_prog_add); 1944 1945 void bpf_prog_sub(struct bpf_prog *prog, int i) 1946 { 1947 /* Only to be used for undoing previous bpf_prog_add() in some 1948 * error path. We still know that another entity in our call 1949 * path holds a reference to the program, thus atomic_sub() can 1950 * be safely used in such cases! 1951 */ 1952 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1953 } 1954 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1955 1956 void bpf_prog_inc(struct bpf_prog *prog) 1957 { 1958 atomic64_inc(&prog->aux->refcnt); 1959 } 1960 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1961 1962 /* prog_idr_lock should have been held */ 1963 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1964 { 1965 int refold; 1966 1967 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1968 1969 if (!refold) 1970 return ERR_PTR(-ENOENT); 1971 1972 return prog; 1973 } 1974 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1975 1976 bool bpf_prog_get_ok(struct bpf_prog *prog, 1977 enum bpf_prog_type *attach_type, bool attach_drv) 1978 { 1979 /* not an attachment, just a refcount inc, always allow */ 1980 if (!attach_type) 1981 return true; 1982 1983 if (prog->type != *attach_type) 1984 return false; 1985 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1986 return false; 1987 1988 return true; 1989 } 1990 1991 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1992 bool attach_drv) 1993 { 1994 struct fd f = fdget(ufd); 1995 struct bpf_prog *prog; 1996 1997 prog = ____bpf_prog_get(f); 1998 if (IS_ERR(prog)) 1999 return prog; 2000 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 2001 prog = ERR_PTR(-EINVAL); 2002 goto out; 2003 } 2004 2005 bpf_prog_inc(prog); 2006 out: 2007 fdput(f); 2008 return prog; 2009 } 2010 2011 struct bpf_prog *bpf_prog_get(u32 ufd) 2012 { 2013 return __bpf_prog_get(ufd, NULL, false); 2014 } 2015 2016 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2017 bool attach_drv) 2018 { 2019 return __bpf_prog_get(ufd, &type, attach_drv); 2020 } 2021 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2022 2023 /* Initially all BPF programs could be loaded w/o specifying 2024 * expected_attach_type. Later for some of them specifying expected_attach_type 2025 * at load time became required so that program could be validated properly. 2026 * Programs of types that are allowed to be loaded both w/ and w/o (for 2027 * backward compatibility) expected_attach_type, should have the default attach 2028 * type assigned to expected_attach_type for the latter case, so that it can be 2029 * validated later at attach time. 2030 * 2031 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2032 * prog type requires it but has some attach types that have to be backward 2033 * compatible. 2034 */ 2035 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2036 { 2037 switch (attr->prog_type) { 2038 case BPF_PROG_TYPE_CGROUP_SOCK: 2039 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2040 * exist so checking for non-zero is the way to go here. 2041 */ 2042 if (!attr->expected_attach_type) 2043 attr->expected_attach_type = 2044 BPF_CGROUP_INET_SOCK_CREATE; 2045 break; 2046 case BPF_PROG_TYPE_SK_REUSEPORT: 2047 if (!attr->expected_attach_type) 2048 attr->expected_attach_type = 2049 BPF_SK_REUSEPORT_SELECT; 2050 break; 2051 } 2052 } 2053 2054 static int 2055 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2056 enum bpf_attach_type expected_attach_type, 2057 struct btf *attach_btf, u32 btf_id, 2058 struct bpf_prog *dst_prog) 2059 { 2060 if (btf_id) { 2061 if (btf_id > BTF_MAX_TYPE) 2062 return -EINVAL; 2063 2064 if (!attach_btf && !dst_prog) 2065 return -EINVAL; 2066 2067 switch (prog_type) { 2068 case BPF_PROG_TYPE_TRACING: 2069 case BPF_PROG_TYPE_LSM: 2070 case BPF_PROG_TYPE_STRUCT_OPS: 2071 case BPF_PROG_TYPE_EXT: 2072 break; 2073 default: 2074 return -EINVAL; 2075 } 2076 } 2077 2078 if (attach_btf && (!btf_id || dst_prog)) 2079 return -EINVAL; 2080 2081 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2082 prog_type != BPF_PROG_TYPE_EXT) 2083 return -EINVAL; 2084 2085 switch (prog_type) { 2086 case BPF_PROG_TYPE_CGROUP_SOCK: 2087 switch (expected_attach_type) { 2088 case BPF_CGROUP_INET_SOCK_CREATE: 2089 case BPF_CGROUP_INET_SOCK_RELEASE: 2090 case BPF_CGROUP_INET4_POST_BIND: 2091 case BPF_CGROUP_INET6_POST_BIND: 2092 return 0; 2093 default: 2094 return -EINVAL; 2095 } 2096 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2097 switch (expected_attach_type) { 2098 case BPF_CGROUP_INET4_BIND: 2099 case BPF_CGROUP_INET6_BIND: 2100 case BPF_CGROUP_INET4_CONNECT: 2101 case BPF_CGROUP_INET6_CONNECT: 2102 case BPF_CGROUP_INET4_GETPEERNAME: 2103 case BPF_CGROUP_INET6_GETPEERNAME: 2104 case BPF_CGROUP_INET4_GETSOCKNAME: 2105 case BPF_CGROUP_INET6_GETSOCKNAME: 2106 case BPF_CGROUP_UDP4_SENDMSG: 2107 case BPF_CGROUP_UDP6_SENDMSG: 2108 case BPF_CGROUP_UDP4_RECVMSG: 2109 case BPF_CGROUP_UDP6_RECVMSG: 2110 return 0; 2111 default: 2112 return -EINVAL; 2113 } 2114 case BPF_PROG_TYPE_CGROUP_SKB: 2115 switch (expected_attach_type) { 2116 case BPF_CGROUP_INET_INGRESS: 2117 case BPF_CGROUP_INET_EGRESS: 2118 return 0; 2119 default: 2120 return -EINVAL; 2121 } 2122 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2123 switch (expected_attach_type) { 2124 case BPF_CGROUP_SETSOCKOPT: 2125 case BPF_CGROUP_GETSOCKOPT: 2126 return 0; 2127 default: 2128 return -EINVAL; 2129 } 2130 case BPF_PROG_TYPE_SK_LOOKUP: 2131 if (expected_attach_type == BPF_SK_LOOKUP) 2132 return 0; 2133 return -EINVAL; 2134 case BPF_PROG_TYPE_SK_REUSEPORT: 2135 switch (expected_attach_type) { 2136 case BPF_SK_REUSEPORT_SELECT: 2137 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2138 return 0; 2139 default: 2140 return -EINVAL; 2141 } 2142 case BPF_PROG_TYPE_SYSCALL: 2143 case BPF_PROG_TYPE_EXT: 2144 if (expected_attach_type) 2145 return -EINVAL; 2146 fallthrough; 2147 default: 2148 return 0; 2149 } 2150 } 2151 2152 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2153 { 2154 switch (prog_type) { 2155 case BPF_PROG_TYPE_SCHED_CLS: 2156 case BPF_PROG_TYPE_SCHED_ACT: 2157 case BPF_PROG_TYPE_XDP: 2158 case BPF_PROG_TYPE_LWT_IN: 2159 case BPF_PROG_TYPE_LWT_OUT: 2160 case BPF_PROG_TYPE_LWT_XMIT: 2161 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2162 case BPF_PROG_TYPE_SK_SKB: 2163 case BPF_PROG_TYPE_SK_MSG: 2164 case BPF_PROG_TYPE_LIRC_MODE2: 2165 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2166 case BPF_PROG_TYPE_CGROUP_DEVICE: 2167 case BPF_PROG_TYPE_CGROUP_SOCK: 2168 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2169 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2170 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2171 case BPF_PROG_TYPE_SOCK_OPS: 2172 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2173 return true; 2174 case BPF_PROG_TYPE_CGROUP_SKB: 2175 /* always unpriv */ 2176 case BPF_PROG_TYPE_SK_REUSEPORT: 2177 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2178 default: 2179 return false; 2180 } 2181 } 2182 2183 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2184 { 2185 switch (prog_type) { 2186 case BPF_PROG_TYPE_KPROBE: 2187 case BPF_PROG_TYPE_TRACEPOINT: 2188 case BPF_PROG_TYPE_PERF_EVENT: 2189 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2190 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2191 case BPF_PROG_TYPE_TRACING: 2192 case BPF_PROG_TYPE_LSM: 2193 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2194 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2195 return true; 2196 default: 2197 return false; 2198 } 2199 } 2200 2201 /* last field in 'union bpf_attr' used by this command */ 2202 #define BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size 2203 2204 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr) 2205 { 2206 enum bpf_prog_type type = attr->prog_type; 2207 struct bpf_prog *prog, *dst_prog = NULL; 2208 struct btf *attach_btf = NULL; 2209 int err; 2210 char license[128]; 2211 bool is_gpl; 2212 2213 if (CHECK_ATTR(BPF_PROG_LOAD)) 2214 return -EINVAL; 2215 2216 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2217 BPF_F_ANY_ALIGNMENT | 2218 BPF_F_TEST_STATE_FREQ | 2219 BPF_F_SLEEPABLE | 2220 BPF_F_TEST_RND_HI32 | 2221 BPF_F_XDP_HAS_FRAGS)) 2222 return -EINVAL; 2223 2224 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2225 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2226 !bpf_capable()) 2227 return -EPERM; 2228 2229 /* copy eBPF program license from user space */ 2230 if (strncpy_from_bpfptr(license, 2231 make_bpfptr(attr->license, uattr.is_kernel), 2232 sizeof(license) - 1) < 0) 2233 return -EFAULT; 2234 license[sizeof(license) - 1] = 0; 2235 2236 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2237 is_gpl = license_is_gpl_compatible(license); 2238 2239 if (attr->insn_cnt == 0 || 2240 attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2241 return -E2BIG; 2242 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2243 type != BPF_PROG_TYPE_CGROUP_SKB && 2244 !bpf_capable()) 2245 return -EPERM; 2246 2247 if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN)) 2248 return -EPERM; 2249 if (is_perfmon_prog_type(type) && !perfmon_capable()) 2250 return -EPERM; 2251 2252 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2253 * or btf, we need to check which one it is 2254 */ 2255 if (attr->attach_prog_fd) { 2256 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2257 if (IS_ERR(dst_prog)) { 2258 dst_prog = NULL; 2259 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2260 if (IS_ERR(attach_btf)) 2261 return -EINVAL; 2262 if (!btf_is_kernel(attach_btf)) { 2263 /* attaching through specifying bpf_prog's BTF 2264 * objects directly might be supported eventually 2265 */ 2266 btf_put(attach_btf); 2267 return -ENOTSUPP; 2268 } 2269 } 2270 } else if (attr->attach_btf_id) { 2271 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2272 attach_btf = bpf_get_btf_vmlinux(); 2273 if (IS_ERR(attach_btf)) 2274 return PTR_ERR(attach_btf); 2275 if (!attach_btf) 2276 return -EINVAL; 2277 btf_get(attach_btf); 2278 } 2279 2280 bpf_prog_load_fixup_attach_type(attr); 2281 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2282 attach_btf, attr->attach_btf_id, 2283 dst_prog)) { 2284 if (dst_prog) 2285 bpf_prog_put(dst_prog); 2286 if (attach_btf) 2287 btf_put(attach_btf); 2288 return -EINVAL; 2289 } 2290 2291 /* plain bpf_prog allocation */ 2292 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2293 if (!prog) { 2294 if (dst_prog) 2295 bpf_prog_put(dst_prog); 2296 if (attach_btf) 2297 btf_put(attach_btf); 2298 return -ENOMEM; 2299 } 2300 2301 prog->expected_attach_type = attr->expected_attach_type; 2302 prog->aux->attach_btf = attach_btf; 2303 prog->aux->attach_btf_id = attr->attach_btf_id; 2304 prog->aux->dst_prog = dst_prog; 2305 prog->aux->offload_requested = !!attr->prog_ifindex; 2306 prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; 2307 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 2308 2309 err = security_bpf_prog_alloc(prog->aux); 2310 if (err) 2311 goto free_prog; 2312 2313 prog->aux->user = get_current_user(); 2314 prog->len = attr->insn_cnt; 2315 2316 err = -EFAULT; 2317 if (copy_from_bpfptr(prog->insns, 2318 make_bpfptr(attr->insns, uattr.is_kernel), 2319 bpf_prog_insn_size(prog)) != 0) 2320 goto free_prog_sec; 2321 2322 prog->orig_prog = NULL; 2323 prog->jited = 0; 2324 2325 atomic64_set(&prog->aux->refcnt, 1); 2326 prog->gpl_compatible = is_gpl ? 1 : 0; 2327 2328 if (bpf_prog_is_dev_bound(prog->aux)) { 2329 err = bpf_prog_offload_init(prog, attr); 2330 if (err) 2331 goto free_prog_sec; 2332 } 2333 2334 /* find program type: socket_filter vs tracing_filter */ 2335 err = find_prog_type(type, prog); 2336 if (err < 0) 2337 goto free_prog_sec; 2338 2339 prog->aux->load_time = ktime_get_boottime_ns(); 2340 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2341 sizeof(attr->prog_name)); 2342 if (err < 0) 2343 goto free_prog_sec; 2344 2345 /* run eBPF verifier */ 2346 err = bpf_check(&prog, attr, uattr); 2347 if (err < 0) 2348 goto free_used_maps; 2349 2350 prog = bpf_prog_select_runtime(prog, &err); 2351 if (err < 0) 2352 goto free_used_maps; 2353 2354 err = bpf_prog_alloc_id(prog); 2355 if (err) 2356 goto free_used_maps; 2357 2358 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2359 * effectively publicly exposed. However, retrieving via 2360 * bpf_prog_get_fd_by_id() will take another reference, 2361 * therefore it cannot be gone underneath us. 2362 * 2363 * Only for the time /after/ successful bpf_prog_new_fd() 2364 * and before returning to userspace, we might just hold 2365 * one reference and any parallel close on that fd could 2366 * rip everything out. Hence, below notifications must 2367 * happen before bpf_prog_new_fd(). 2368 * 2369 * Also, any failure handling from this point onwards must 2370 * be using bpf_prog_put() given the program is exposed. 2371 */ 2372 bpf_prog_kallsyms_add(prog); 2373 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2374 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2375 2376 err = bpf_prog_new_fd(prog); 2377 if (err < 0) 2378 bpf_prog_put(prog); 2379 return err; 2380 2381 free_used_maps: 2382 /* In case we have subprogs, we need to wait for a grace 2383 * period before we can tear down JIT memory since symbols 2384 * are already exposed under kallsyms. 2385 */ 2386 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2387 return err; 2388 free_prog_sec: 2389 free_uid(prog->aux->user); 2390 security_bpf_prog_free(prog->aux); 2391 free_prog: 2392 if (prog->aux->attach_btf) 2393 btf_put(prog->aux->attach_btf); 2394 bpf_prog_free(prog); 2395 return err; 2396 } 2397 2398 #define BPF_OBJ_LAST_FIELD file_flags 2399 2400 static int bpf_obj_pin(const union bpf_attr *attr) 2401 { 2402 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2403 return -EINVAL; 2404 2405 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2406 } 2407 2408 static int bpf_obj_get(const union bpf_attr *attr) 2409 { 2410 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2411 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2412 return -EINVAL; 2413 2414 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2415 attr->file_flags); 2416 } 2417 2418 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2419 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2420 { 2421 atomic64_set(&link->refcnt, 1); 2422 link->type = type; 2423 link->id = 0; 2424 link->ops = ops; 2425 link->prog = prog; 2426 } 2427 2428 static void bpf_link_free_id(int id) 2429 { 2430 if (!id) 2431 return; 2432 2433 spin_lock_bh(&link_idr_lock); 2434 idr_remove(&link_idr, id); 2435 spin_unlock_bh(&link_idr_lock); 2436 } 2437 2438 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2439 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2440 * anon_inode's release() call. This helper marksbpf_link as 2441 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 2442 * is not decremented, it's the responsibility of a calling code that failed 2443 * to complete bpf_link initialization. 2444 */ 2445 void bpf_link_cleanup(struct bpf_link_primer *primer) 2446 { 2447 primer->link->prog = NULL; 2448 bpf_link_free_id(primer->id); 2449 fput(primer->file); 2450 put_unused_fd(primer->fd); 2451 } 2452 2453 void bpf_link_inc(struct bpf_link *link) 2454 { 2455 atomic64_inc(&link->refcnt); 2456 } 2457 2458 /* bpf_link_free is guaranteed to be called from process context */ 2459 static void bpf_link_free(struct bpf_link *link) 2460 { 2461 bpf_link_free_id(link->id); 2462 if (link->prog) { 2463 /* detach BPF program, clean up used resources */ 2464 link->ops->release(link); 2465 bpf_prog_put(link->prog); 2466 } 2467 /* free bpf_link and its containing memory */ 2468 link->ops->dealloc(link); 2469 } 2470 2471 static void bpf_link_put_deferred(struct work_struct *work) 2472 { 2473 struct bpf_link *link = container_of(work, struct bpf_link, work); 2474 2475 bpf_link_free(link); 2476 } 2477 2478 /* bpf_link_put can be called from atomic context, but ensures that resources 2479 * are freed from process context 2480 */ 2481 void bpf_link_put(struct bpf_link *link) 2482 { 2483 if (!atomic64_dec_and_test(&link->refcnt)) 2484 return; 2485 2486 if (in_atomic()) { 2487 INIT_WORK(&link->work, bpf_link_put_deferred); 2488 schedule_work(&link->work); 2489 } else { 2490 bpf_link_free(link); 2491 } 2492 } 2493 EXPORT_SYMBOL(bpf_link_put); 2494 2495 static int bpf_link_release(struct inode *inode, struct file *filp) 2496 { 2497 struct bpf_link *link = filp->private_data; 2498 2499 bpf_link_put(link); 2500 return 0; 2501 } 2502 2503 #ifdef CONFIG_PROC_FS 2504 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 2505 #define BPF_MAP_TYPE(_id, _ops) 2506 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 2507 static const char *bpf_link_type_strs[] = { 2508 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 2509 #include <linux/bpf_types.h> 2510 }; 2511 #undef BPF_PROG_TYPE 2512 #undef BPF_MAP_TYPE 2513 #undef BPF_LINK_TYPE 2514 2515 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2516 { 2517 const struct bpf_link *link = filp->private_data; 2518 const struct bpf_prog *prog = link->prog; 2519 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2520 2521 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2522 seq_printf(m, 2523 "link_type:\t%s\n" 2524 "link_id:\t%u\n" 2525 "prog_tag:\t%s\n" 2526 "prog_id:\t%u\n", 2527 bpf_link_type_strs[link->type], 2528 link->id, 2529 prog_tag, 2530 prog->aux->id); 2531 if (link->ops->show_fdinfo) 2532 link->ops->show_fdinfo(link, m); 2533 } 2534 #endif 2535 2536 static const struct file_operations bpf_link_fops = { 2537 #ifdef CONFIG_PROC_FS 2538 .show_fdinfo = bpf_link_show_fdinfo, 2539 #endif 2540 .release = bpf_link_release, 2541 .read = bpf_dummy_read, 2542 .write = bpf_dummy_write, 2543 }; 2544 2545 static int bpf_link_alloc_id(struct bpf_link *link) 2546 { 2547 int id; 2548 2549 idr_preload(GFP_KERNEL); 2550 spin_lock_bh(&link_idr_lock); 2551 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 2552 spin_unlock_bh(&link_idr_lock); 2553 idr_preload_end(); 2554 2555 return id; 2556 } 2557 2558 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 2559 * reserving unused FD and allocating ID from link_idr. This is to be paired 2560 * with bpf_link_settle() to install FD and ID and expose bpf_link to 2561 * user-space, if bpf_link is successfully attached. If not, bpf_link and 2562 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 2563 * transient state is passed around in struct bpf_link_primer. 2564 * This is preferred way to create and initialize bpf_link, especially when 2565 * there are complicated and expensive operations inbetween creating bpf_link 2566 * itself and attaching it to BPF hook. By using bpf_link_prime() and 2567 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 2568 * expensive (and potentially failing) roll back operations in a rare case 2569 * that file, FD, or ID can't be allocated. 2570 */ 2571 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 2572 { 2573 struct file *file; 2574 int fd, id; 2575 2576 fd = get_unused_fd_flags(O_CLOEXEC); 2577 if (fd < 0) 2578 return fd; 2579 2580 2581 id = bpf_link_alloc_id(link); 2582 if (id < 0) { 2583 put_unused_fd(fd); 2584 return id; 2585 } 2586 2587 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2588 if (IS_ERR(file)) { 2589 bpf_link_free_id(id); 2590 put_unused_fd(fd); 2591 return PTR_ERR(file); 2592 } 2593 2594 primer->link = link; 2595 primer->file = file; 2596 primer->fd = fd; 2597 primer->id = id; 2598 return 0; 2599 } 2600 2601 int bpf_link_settle(struct bpf_link_primer *primer) 2602 { 2603 /* make bpf_link fetchable by ID */ 2604 spin_lock_bh(&link_idr_lock); 2605 primer->link->id = primer->id; 2606 spin_unlock_bh(&link_idr_lock); 2607 /* make bpf_link fetchable by FD */ 2608 fd_install(primer->fd, primer->file); 2609 /* pass through installed FD */ 2610 return primer->fd; 2611 } 2612 2613 int bpf_link_new_fd(struct bpf_link *link) 2614 { 2615 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2616 } 2617 2618 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2619 { 2620 struct fd f = fdget(ufd); 2621 struct bpf_link *link; 2622 2623 if (!f.file) 2624 return ERR_PTR(-EBADF); 2625 if (f.file->f_op != &bpf_link_fops) { 2626 fdput(f); 2627 return ERR_PTR(-EINVAL); 2628 } 2629 2630 link = f.file->private_data; 2631 bpf_link_inc(link); 2632 fdput(f); 2633 2634 return link; 2635 } 2636 EXPORT_SYMBOL(bpf_link_get_from_fd); 2637 2638 struct bpf_tracing_link { 2639 struct bpf_link link; 2640 enum bpf_attach_type attach_type; 2641 struct bpf_trampoline *trampoline; 2642 struct bpf_prog *tgt_prog; 2643 }; 2644 2645 static void bpf_tracing_link_release(struct bpf_link *link) 2646 { 2647 struct bpf_tracing_link *tr_link = 2648 container_of(link, struct bpf_tracing_link, link); 2649 2650 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, 2651 tr_link->trampoline)); 2652 2653 bpf_trampoline_put(tr_link->trampoline); 2654 2655 /* tgt_prog is NULL if target is a kernel function */ 2656 if (tr_link->tgt_prog) 2657 bpf_prog_put(tr_link->tgt_prog); 2658 } 2659 2660 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2661 { 2662 struct bpf_tracing_link *tr_link = 2663 container_of(link, struct bpf_tracing_link, link); 2664 2665 kfree(tr_link); 2666 } 2667 2668 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 2669 struct seq_file *seq) 2670 { 2671 struct bpf_tracing_link *tr_link = 2672 container_of(link, struct bpf_tracing_link, link); 2673 2674 seq_printf(seq, 2675 "attach_type:\t%d\n", 2676 tr_link->attach_type); 2677 } 2678 2679 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 2680 struct bpf_link_info *info) 2681 { 2682 struct bpf_tracing_link *tr_link = 2683 container_of(link, struct bpf_tracing_link, link); 2684 2685 info->tracing.attach_type = tr_link->attach_type; 2686 bpf_trampoline_unpack_key(tr_link->trampoline->key, 2687 &info->tracing.target_obj_id, 2688 &info->tracing.target_btf_id); 2689 2690 return 0; 2691 } 2692 2693 static const struct bpf_link_ops bpf_tracing_link_lops = { 2694 .release = bpf_tracing_link_release, 2695 .dealloc = bpf_tracing_link_dealloc, 2696 .show_fdinfo = bpf_tracing_link_show_fdinfo, 2697 .fill_link_info = bpf_tracing_link_fill_link_info, 2698 }; 2699 2700 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 2701 int tgt_prog_fd, 2702 u32 btf_id) 2703 { 2704 struct bpf_link_primer link_primer; 2705 struct bpf_prog *tgt_prog = NULL; 2706 struct bpf_trampoline *tr = NULL; 2707 struct bpf_tracing_link *link; 2708 u64 key = 0; 2709 int err; 2710 2711 switch (prog->type) { 2712 case BPF_PROG_TYPE_TRACING: 2713 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2714 prog->expected_attach_type != BPF_TRACE_FEXIT && 2715 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2716 err = -EINVAL; 2717 goto out_put_prog; 2718 } 2719 break; 2720 case BPF_PROG_TYPE_EXT: 2721 if (prog->expected_attach_type != 0) { 2722 err = -EINVAL; 2723 goto out_put_prog; 2724 } 2725 break; 2726 case BPF_PROG_TYPE_LSM: 2727 if (prog->expected_attach_type != BPF_LSM_MAC) { 2728 err = -EINVAL; 2729 goto out_put_prog; 2730 } 2731 break; 2732 default: 2733 err = -EINVAL; 2734 goto out_put_prog; 2735 } 2736 2737 if (!!tgt_prog_fd != !!btf_id) { 2738 err = -EINVAL; 2739 goto out_put_prog; 2740 } 2741 2742 if (tgt_prog_fd) { 2743 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */ 2744 if (prog->type != BPF_PROG_TYPE_EXT) { 2745 err = -EINVAL; 2746 goto out_put_prog; 2747 } 2748 2749 tgt_prog = bpf_prog_get(tgt_prog_fd); 2750 if (IS_ERR(tgt_prog)) { 2751 err = PTR_ERR(tgt_prog); 2752 tgt_prog = NULL; 2753 goto out_put_prog; 2754 } 2755 2756 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 2757 } 2758 2759 link = kzalloc(sizeof(*link), GFP_USER); 2760 if (!link) { 2761 err = -ENOMEM; 2762 goto out_put_prog; 2763 } 2764 bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, 2765 &bpf_tracing_link_lops, prog); 2766 link->attach_type = prog->expected_attach_type; 2767 2768 mutex_lock(&prog->aux->dst_mutex); 2769 2770 /* There are a few possible cases here: 2771 * 2772 * - if prog->aux->dst_trampoline is set, the program was just loaded 2773 * and not yet attached to anything, so we can use the values stored 2774 * in prog->aux 2775 * 2776 * - if prog->aux->dst_trampoline is NULL, the program has already been 2777 * attached to a target and its initial target was cleared (below) 2778 * 2779 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 2780 * target_btf_id using the link_create API. 2781 * 2782 * - if tgt_prog == NULL when this function was called using the old 2783 * raw_tracepoint_open API, and we need a target from prog->aux 2784 * 2785 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 2786 * was detached and is going for re-attachment. 2787 */ 2788 if (!prog->aux->dst_trampoline && !tgt_prog) { 2789 /* 2790 * Allow re-attach for TRACING and LSM programs. If it's 2791 * currently linked, bpf_trampoline_link_prog will fail. 2792 * EXT programs need to specify tgt_prog_fd, so they 2793 * re-attach in separate code path. 2794 */ 2795 if (prog->type != BPF_PROG_TYPE_TRACING && 2796 prog->type != BPF_PROG_TYPE_LSM) { 2797 err = -EINVAL; 2798 goto out_unlock; 2799 } 2800 btf_id = prog->aux->attach_btf_id; 2801 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 2802 } 2803 2804 if (!prog->aux->dst_trampoline || 2805 (key && key != prog->aux->dst_trampoline->key)) { 2806 /* If there is no saved target, or the specified target is 2807 * different from the destination specified at load time, we 2808 * need a new trampoline and a check for compatibility 2809 */ 2810 struct bpf_attach_target_info tgt_info = {}; 2811 2812 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 2813 &tgt_info); 2814 if (err) 2815 goto out_unlock; 2816 2817 tr = bpf_trampoline_get(key, &tgt_info); 2818 if (!tr) { 2819 err = -ENOMEM; 2820 goto out_unlock; 2821 } 2822 } else { 2823 /* The caller didn't specify a target, or the target was the 2824 * same as the destination supplied during program load. This 2825 * means we can reuse the trampoline and reference from program 2826 * load time, and there is no need to allocate a new one. This 2827 * can only happen once for any program, as the saved values in 2828 * prog->aux are cleared below. 2829 */ 2830 tr = prog->aux->dst_trampoline; 2831 tgt_prog = prog->aux->dst_prog; 2832 } 2833 2834 err = bpf_link_prime(&link->link, &link_primer); 2835 if (err) 2836 goto out_unlock; 2837 2838 err = bpf_trampoline_link_prog(prog, tr); 2839 if (err) { 2840 bpf_link_cleanup(&link_primer); 2841 link = NULL; 2842 goto out_unlock; 2843 } 2844 2845 link->tgt_prog = tgt_prog; 2846 link->trampoline = tr; 2847 2848 /* Always clear the trampoline and target prog from prog->aux to make 2849 * sure the original attach destination is not kept alive after a 2850 * program is (re-)attached to another target. 2851 */ 2852 if (prog->aux->dst_prog && 2853 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 2854 /* got extra prog ref from syscall, or attaching to different prog */ 2855 bpf_prog_put(prog->aux->dst_prog); 2856 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 2857 /* we allocated a new trampoline, so free the old one */ 2858 bpf_trampoline_put(prog->aux->dst_trampoline); 2859 2860 prog->aux->dst_prog = NULL; 2861 prog->aux->dst_trampoline = NULL; 2862 mutex_unlock(&prog->aux->dst_mutex); 2863 2864 return bpf_link_settle(&link_primer); 2865 out_unlock: 2866 if (tr && tr != prog->aux->dst_trampoline) 2867 bpf_trampoline_put(tr); 2868 mutex_unlock(&prog->aux->dst_mutex); 2869 kfree(link); 2870 out_put_prog: 2871 if (tgt_prog_fd && tgt_prog) 2872 bpf_prog_put(tgt_prog); 2873 return err; 2874 } 2875 2876 struct bpf_raw_tp_link { 2877 struct bpf_link link; 2878 struct bpf_raw_event_map *btp; 2879 }; 2880 2881 static void bpf_raw_tp_link_release(struct bpf_link *link) 2882 { 2883 struct bpf_raw_tp_link *raw_tp = 2884 container_of(link, struct bpf_raw_tp_link, link); 2885 2886 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2887 bpf_put_raw_tracepoint(raw_tp->btp); 2888 } 2889 2890 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2891 { 2892 struct bpf_raw_tp_link *raw_tp = 2893 container_of(link, struct bpf_raw_tp_link, link); 2894 2895 kfree(raw_tp); 2896 } 2897 2898 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 2899 struct seq_file *seq) 2900 { 2901 struct bpf_raw_tp_link *raw_tp_link = 2902 container_of(link, struct bpf_raw_tp_link, link); 2903 2904 seq_printf(seq, 2905 "tp_name:\t%s\n", 2906 raw_tp_link->btp->tp->name); 2907 } 2908 2909 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 2910 struct bpf_link_info *info) 2911 { 2912 struct bpf_raw_tp_link *raw_tp_link = 2913 container_of(link, struct bpf_raw_tp_link, link); 2914 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 2915 const char *tp_name = raw_tp_link->btp->tp->name; 2916 u32 ulen = info->raw_tracepoint.tp_name_len; 2917 size_t tp_len = strlen(tp_name); 2918 2919 if (!ulen ^ !ubuf) 2920 return -EINVAL; 2921 2922 info->raw_tracepoint.tp_name_len = tp_len + 1; 2923 2924 if (!ubuf) 2925 return 0; 2926 2927 if (ulen >= tp_len + 1) { 2928 if (copy_to_user(ubuf, tp_name, tp_len + 1)) 2929 return -EFAULT; 2930 } else { 2931 char zero = '\0'; 2932 2933 if (copy_to_user(ubuf, tp_name, ulen - 1)) 2934 return -EFAULT; 2935 if (put_user(zero, ubuf + ulen - 1)) 2936 return -EFAULT; 2937 return -ENOSPC; 2938 } 2939 2940 return 0; 2941 } 2942 2943 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 2944 .release = bpf_raw_tp_link_release, 2945 .dealloc = bpf_raw_tp_link_dealloc, 2946 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 2947 .fill_link_info = bpf_raw_tp_link_fill_link_info, 2948 }; 2949 2950 #ifdef CONFIG_PERF_EVENTS 2951 struct bpf_perf_link { 2952 struct bpf_link link; 2953 struct file *perf_file; 2954 }; 2955 2956 static void bpf_perf_link_release(struct bpf_link *link) 2957 { 2958 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2959 struct perf_event *event = perf_link->perf_file->private_data; 2960 2961 perf_event_free_bpf_prog(event); 2962 fput(perf_link->perf_file); 2963 } 2964 2965 static void bpf_perf_link_dealloc(struct bpf_link *link) 2966 { 2967 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 2968 2969 kfree(perf_link); 2970 } 2971 2972 static const struct bpf_link_ops bpf_perf_link_lops = { 2973 .release = bpf_perf_link_release, 2974 .dealloc = bpf_perf_link_dealloc, 2975 }; 2976 2977 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 2978 { 2979 struct bpf_link_primer link_primer; 2980 struct bpf_perf_link *link; 2981 struct perf_event *event; 2982 struct file *perf_file; 2983 int err; 2984 2985 if (attr->link_create.flags) 2986 return -EINVAL; 2987 2988 perf_file = perf_event_get(attr->link_create.target_fd); 2989 if (IS_ERR(perf_file)) 2990 return PTR_ERR(perf_file); 2991 2992 link = kzalloc(sizeof(*link), GFP_USER); 2993 if (!link) { 2994 err = -ENOMEM; 2995 goto out_put_file; 2996 } 2997 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 2998 link->perf_file = perf_file; 2999 3000 err = bpf_link_prime(&link->link, &link_primer); 3001 if (err) { 3002 kfree(link); 3003 goto out_put_file; 3004 } 3005 3006 event = perf_file->private_data; 3007 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3008 if (err) { 3009 bpf_link_cleanup(&link_primer); 3010 goto out_put_file; 3011 } 3012 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3013 bpf_prog_inc(prog); 3014 3015 return bpf_link_settle(&link_primer); 3016 3017 out_put_file: 3018 fput(perf_file); 3019 return err; 3020 } 3021 #endif /* CONFIG_PERF_EVENTS */ 3022 3023 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 3024 3025 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3026 { 3027 struct bpf_link_primer link_primer; 3028 struct bpf_raw_tp_link *link; 3029 struct bpf_raw_event_map *btp; 3030 struct bpf_prog *prog; 3031 const char *tp_name; 3032 char buf[128]; 3033 int err; 3034 3035 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3036 return -EINVAL; 3037 3038 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3039 if (IS_ERR(prog)) 3040 return PTR_ERR(prog); 3041 3042 switch (prog->type) { 3043 case BPF_PROG_TYPE_TRACING: 3044 case BPF_PROG_TYPE_EXT: 3045 case BPF_PROG_TYPE_LSM: 3046 if (attr->raw_tracepoint.name) { 3047 /* The attach point for this category of programs 3048 * should be specified via btf_id during program load. 3049 */ 3050 err = -EINVAL; 3051 goto out_put_prog; 3052 } 3053 if (prog->type == BPF_PROG_TYPE_TRACING && 3054 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3055 tp_name = prog->aux->attach_func_name; 3056 break; 3057 } 3058 err = bpf_tracing_prog_attach(prog, 0, 0); 3059 if (err >= 0) 3060 return err; 3061 goto out_put_prog; 3062 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3063 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3064 if (strncpy_from_user(buf, 3065 u64_to_user_ptr(attr->raw_tracepoint.name), 3066 sizeof(buf) - 1) < 0) { 3067 err = -EFAULT; 3068 goto out_put_prog; 3069 } 3070 buf[sizeof(buf) - 1] = 0; 3071 tp_name = buf; 3072 break; 3073 default: 3074 err = -EINVAL; 3075 goto out_put_prog; 3076 } 3077 3078 btp = bpf_get_raw_tracepoint(tp_name); 3079 if (!btp) { 3080 err = -ENOENT; 3081 goto out_put_prog; 3082 } 3083 3084 link = kzalloc(sizeof(*link), GFP_USER); 3085 if (!link) { 3086 err = -ENOMEM; 3087 goto out_put_btp; 3088 } 3089 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3090 &bpf_raw_tp_link_lops, prog); 3091 link->btp = btp; 3092 3093 err = bpf_link_prime(&link->link, &link_primer); 3094 if (err) { 3095 kfree(link); 3096 goto out_put_btp; 3097 } 3098 3099 err = bpf_probe_register(link->btp, prog); 3100 if (err) { 3101 bpf_link_cleanup(&link_primer); 3102 goto out_put_btp; 3103 } 3104 3105 return bpf_link_settle(&link_primer); 3106 3107 out_put_btp: 3108 bpf_put_raw_tracepoint(btp); 3109 out_put_prog: 3110 bpf_prog_put(prog); 3111 return err; 3112 } 3113 3114 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3115 enum bpf_attach_type attach_type) 3116 { 3117 switch (prog->type) { 3118 case BPF_PROG_TYPE_CGROUP_SOCK: 3119 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3120 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3121 case BPF_PROG_TYPE_SK_LOOKUP: 3122 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3123 case BPF_PROG_TYPE_CGROUP_SKB: 3124 if (!capable(CAP_NET_ADMIN)) 3125 /* cg-skb progs can be loaded by unpriv user. 3126 * check permissions at attach time. 3127 */ 3128 return -EPERM; 3129 return prog->enforce_expected_attach_type && 3130 prog->expected_attach_type != attach_type ? 3131 -EINVAL : 0; 3132 default: 3133 return 0; 3134 } 3135 } 3136 3137 static enum bpf_prog_type 3138 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3139 { 3140 switch (attach_type) { 3141 case BPF_CGROUP_INET_INGRESS: 3142 case BPF_CGROUP_INET_EGRESS: 3143 return BPF_PROG_TYPE_CGROUP_SKB; 3144 case BPF_CGROUP_INET_SOCK_CREATE: 3145 case BPF_CGROUP_INET_SOCK_RELEASE: 3146 case BPF_CGROUP_INET4_POST_BIND: 3147 case BPF_CGROUP_INET6_POST_BIND: 3148 return BPF_PROG_TYPE_CGROUP_SOCK; 3149 case BPF_CGROUP_INET4_BIND: 3150 case BPF_CGROUP_INET6_BIND: 3151 case BPF_CGROUP_INET4_CONNECT: 3152 case BPF_CGROUP_INET6_CONNECT: 3153 case BPF_CGROUP_INET4_GETPEERNAME: 3154 case BPF_CGROUP_INET6_GETPEERNAME: 3155 case BPF_CGROUP_INET4_GETSOCKNAME: 3156 case BPF_CGROUP_INET6_GETSOCKNAME: 3157 case BPF_CGROUP_UDP4_SENDMSG: 3158 case BPF_CGROUP_UDP6_SENDMSG: 3159 case BPF_CGROUP_UDP4_RECVMSG: 3160 case BPF_CGROUP_UDP6_RECVMSG: 3161 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3162 case BPF_CGROUP_SOCK_OPS: 3163 return BPF_PROG_TYPE_SOCK_OPS; 3164 case BPF_CGROUP_DEVICE: 3165 return BPF_PROG_TYPE_CGROUP_DEVICE; 3166 case BPF_SK_MSG_VERDICT: 3167 return BPF_PROG_TYPE_SK_MSG; 3168 case BPF_SK_SKB_STREAM_PARSER: 3169 case BPF_SK_SKB_STREAM_VERDICT: 3170 case BPF_SK_SKB_VERDICT: 3171 return BPF_PROG_TYPE_SK_SKB; 3172 case BPF_LIRC_MODE2: 3173 return BPF_PROG_TYPE_LIRC_MODE2; 3174 case BPF_FLOW_DISSECTOR: 3175 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3176 case BPF_CGROUP_SYSCTL: 3177 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3178 case BPF_CGROUP_GETSOCKOPT: 3179 case BPF_CGROUP_SETSOCKOPT: 3180 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3181 case BPF_TRACE_ITER: 3182 return BPF_PROG_TYPE_TRACING; 3183 case BPF_SK_LOOKUP: 3184 return BPF_PROG_TYPE_SK_LOOKUP; 3185 case BPF_XDP: 3186 return BPF_PROG_TYPE_XDP; 3187 default: 3188 return BPF_PROG_TYPE_UNSPEC; 3189 } 3190 } 3191 3192 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 3193 3194 #define BPF_F_ATTACH_MASK \ 3195 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 3196 3197 static int bpf_prog_attach(const union bpf_attr *attr) 3198 { 3199 enum bpf_prog_type ptype; 3200 struct bpf_prog *prog; 3201 int ret; 3202 3203 if (CHECK_ATTR(BPF_PROG_ATTACH)) 3204 return -EINVAL; 3205 3206 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 3207 return -EINVAL; 3208 3209 ptype = attach_type_to_prog_type(attr->attach_type); 3210 if (ptype == BPF_PROG_TYPE_UNSPEC) 3211 return -EINVAL; 3212 3213 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 3214 if (IS_ERR(prog)) 3215 return PTR_ERR(prog); 3216 3217 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 3218 bpf_prog_put(prog); 3219 return -EINVAL; 3220 } 3221 3222 switch (ptype) { 3223 case BPF_PROG_TYPE_SK_SKB: 3224 case BPF_PROG_TYPE_SK_MSG: 3225 ret = sock_map_get_from_fd(attr, prog); 3226 break; 3227 case BPF_PROG_TYPE_LIRC_MODE2: 3228 ret = lirc_prog_attach(attr, prog); 3229 break; 3230 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3231 ret = netns_bpf_prog_attach(attr, prog); 3232 break; 3233 case BPF_PROG_TYPE_CGROUP_DEVICE: 3234 case BPF_PROG_TYPE_CGROUP_SKB: 3235 case BPF_PROG_TYPE_CGROUP_SOCK: 3236 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3237 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3238 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3239 case BPF_PROG_TYPE_SOCK_OPS: 3240 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 3241 break; 3242 default: 3243 ret = -EINVAL; 3244 } 3245 3246 if (ret) 3247 bpf_prog_put(prog); 3248 return ret; 3249 } 3250 3251 #define BPF_PROG_DETACH_LAST_FIELD attach_type 3252 3253 static int bpf_prog_detach(const union bpf_attr *attr) 3254 { 3255 enum bpf_prog_type ptype; 3256 3257 if (CHECK_ATTR(BPF_PROG_DETACH)) 3258 return -EINVAL; 3259 3260 ptype = attach_type_to_prog_type(attr->attach_type); 3261 3262 switch (ptype) { 3263 case BPF_PROG_TYPE_SK_MSG: 3264 case BPF_PROG_TYPE_SK_SKB: 3265 return sock_map_prog_detach(attr, ptype); 3266 case BPF_PROG_TYPE_LIRC_MODE2: 3267 return lirc_prog_detach(attr); 3268 case BPF_PROG_TYPE_FLOW_DISSECTOR: 3269 return netns_bpf_prog_detach(attr, ptype); 3270 case BPF_PROG_TYPE_CGROUP_DEVICE: 3271 case BPF_PROG_TYPE_CGROUP_SKB: 3272 case BPF_PROG_TYPE_CGROUP_SOCK: 3273 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3274 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3275 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3276 case BPF_PROG_TYPE_SOCK_OPS: 3277 return cgroup_bpf_prog_detach(attr, ptype); 3278 default: 3279 return -EINVAL; 3280 } 3281 } 3282 3283 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 3284 3285 static int bpf_prog_query(const union bpf_attr *attr, 3286 union bpf_attr __user *uattr) 3287 { 3288 if (!capable(CAP_NET_ADMIN)) 3289 return -EPERM; 3290 if (CHECK_ATTR(BPF_PROG_QUERY)) 3291 return -EINVAL; 3292 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 3293 return -EINVAL; 3294 3295 switch (attr->query.attach_type) { 3296 case BPF_CGROUP_INET_INGRESS: 3297 case BPF_CGROUP_INET_EGRESS: 3298 case BPF_CGROUP_INET_SOCK_CREATE: 3299 case BPF_CGROUP_INET_SOCK_RELEASE: 3300 case BPF_CGROUP_INET4_BIND: 3301 case BPF_CGROUP_INET6_BIND: 3302 case BPF_CGROUP_INET4_POST_BIND: 3303 case BPF_CGROUP_INET6_POST_BIND: 3304 case BPF_CGROUP_INET4_CONNECT: 3305 case BPF_CGROUP_INET6_CONNECT: 3306 case BPF_CGROUP_INET4_GETPEERNAME: 3307 case BPF_CGROUP_INET6_GETPEERNAME: 3308 case BPF_CGROUP_INET4_GETSOCKNAME: 3309 case BPF_CGROUP_INET6_GETSOCKNAME: 3310 case BPF_CGROUP_UDP4_SENDMSG: 3311 case BPF_CGROUP_UDP6_SENDMSG: 3312 case BPF_CGROUP_UDP4_RECVMSG: 3313 case BPF_CGROUP_UDP6_RECVMSG: 3314 case BPF_CGROUP_SOCK_OPS: 3315 case BPF_CGROUP_DEVICE: 3316 case BPF_CGROUP_SYSCTL: 3317 case BPF_CGROUP_GETSOCKOPT: 3318 case BPF_CGROUP_SETSOCKOPT: 3319 return cgroup_bpf_prog_query(attr, uattr); 3320 case BPF_LIRC_MODE2: 3321 return lirc_prog_query(attr, uattr); 3322 case BPF_FLOW_DISSECTOR: 3323 case BPF_SK_LOOKUP: 3324 return netns_bpf_prog_query(attr, uattr); 3325 case BPF_SK_SKB_STREAM_PARSER: 3326 case BPF_SK_SKB_STREAM_VERDICT: 3327 case BPF_SK_MSG_VERDICT: 3328 case BPF_SK_SKB_VERDICT: 3329 return sock_map_bpf_prog_query(attr, uattr); 3330 default: 3331 return -EINVAL; 3332 } 3333 } 3334 3335 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu 3336 3337 static int bpf_prog_test_run(const union bpf_attr *attr, 3338 union bpf_attr __user *uattr) 3339 { 3340 struct bpf_prog *prog; 3341 int ret = -ENOTSUPP; 3342 3343 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 3344 return -EINVAL; 3345 3346 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 3347 (!attr->test.ctx_size_in && attr->test.ctx_in)) 3348 return -EINVAL; 3349 3350 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 3351 (!attr->test.ctx_size_out && attr->test.ctx_out)) 3352 return -EINVAL; 3353 3354 prog = bpf_prog_get(attr->test.prog_fd); 3355 if (IS_ERR(prog)) 3356 return PTR_ERR(prog); 3357 3358 if (prog->aux->ops->test_run) 3359 ret = prog->aux->ops->test_run(prog, attr, uattr); 3360 3361 bpf_prog_put(prog); 3362 return ret; 3363 } 3364 3365 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 3366 3367 static int bpf_obj_get_next_id(const union bpf_attr *attr, 3368 union bpf_attr __user *uattr, 3369 struct idr *idr, 3370 spinlock_t *lock) 3371 { 3372 u32 next_id = attr->start_id; 3373 int err = 0; 3374 3375 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 3376 return -EINVAL; 3377 3378 if (!capable(CAP_SYS_ADMIN)) 3379 return -EPERM; 3380 3381 next_id++; 3382 spin_lock_bh(lock); 3383 if (!idr_get_next(idr, &next_id)) 3384 err = -ENOENT; 3385 spin_unlock_bh(lock); 3386 3387 if (!err) 3388 err = put_user(next_id, &uattr->next_id); 3389 3390 return err; 3391 } 3392 3393 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 3394 { 3395 struct bpf_map *map; 3396 3397 spin_lock_bh(&map_idr_lock); 3398 again: 3399 map = idr_get_next(&map_idr, id); 3400 if (map) { 3401 map = __bpf_map_inc_not_zero(map, false); 3402 if (IS_ERR(map)) { 3403 (*id)++; 3404 goto again; 3405 } 3406 } 3407 spin_unlock_bh(&map_idr_lock); 3408 3409 return map; 3410 } 3411 3412 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 3413 { 3414 struct bpf_prog *prog; 3415 3416 spin_lock_bh(&prog_idr_lock); 3417 again: 3418 prog = idr_get_next(&prog_idr, id); 3419 if (prog) { 3420 prog = bpf_prog_inc_not_zero(prog); 3421 if (IS_ERR(prog)) { 3422 (*id)++; 3423 goto again; 3424 } 3425 } 3426 spin_unlock_bh(&prog_idr_lock); 3427 3428 return prog; 3429 } 3430 3431 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 3432 3433 struct bpf_prog *bpf_prog_by_id(u32 id) 3434 { 3435 struct bpf_prog *prog; 3436 3437 if (!id) 3438 return ERR_PTR(-ENOENT); 3439 3440 spin_lock_bh(&prog_idr_lock); 3441 prog = idr_find(&prog_idr, id); 3442 if (prog) 3443 prog = bpf_prog_inc_not_zero(prog); 3444 else 3445 prog = ERR_PTR(-ENOENT); 3446 spin_unlock_bh(&prog_idr_lock); 3447 return prog; 3448 } 3449 3450 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 3451 { 3452 struct bpf_prog *prog; 3453 u32 id = attr->prog_id; 3454 int fd; 3455 3456 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 3457 return -EINVAL; 3458 3459 if (!capable(CAP_SYS_ADMIN)) 3460 return -EPERM; 3461 3462 prog = bpf_prog_by_id(id); 3463 if (IS_ERR(prog)) 3464 return PTR_ERR(prog); 3465 3466 fd = bpf_prog_new_fd(prog); 3467 if (fd < 0) 3468 bpf_prog_put(prog); 3469 3470 return fd; 3471 } 3472 3473 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 3474 3475 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 3476 { 3477 struct bpf_map *map; 3478 u32 id = attr->map_id; 3479 int f_flags; 3480 int fd; 3481 3482 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 3483 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 3484 return -EINVAL; 3485 3486 if (!capable(CAP_SYS_ADMIN)) 3487 return -EPERM; 3488 3489 f_flags = bpf_get_file_flag(attr->open_flags); 3490 if (f_flags < 0) 3491 return f_flags; 3492 3493 spin_lock_bh(&map_idr_lock); 3494 map = idr_find(&map_idr, id); 3495 if (map) 3496 map = __bpf_map_inc_not_zero(map, true); 3497 else 3498 map = ERR_PTR(-ENOENT); 3499 spin_unlock_bh(&map_idr_lock); 3500 3501 if (IS_ERR(map)) 3502 return PTR_ERR(map); 3503 3504 fd = bpf_map_new_fd(map, f_flags); 3505 if (fd < 0) 3506 bpf_map_put_with_uref(map); 3507 3508 return fd; 3509 } 3510 3511 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 3512 unsigned long addr, u32 *off, 3513 u32 *type) 3514 { 3515 const struct bpf_map *map; 3516 int i; 3517 3518 mutex_lock(&prog->aux->used_maps_mutex); 3519 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 3520 map = prog->aux->used_maps[i]; 3521 if (map == (void *)addr) { 3522 *type = BPF_PSEUDO_MAP_FD; 3523 goto out; 3524 } 3525 if (!map->ops->map_direct_value_meta) 3526 continue; 3527 if (!map->ops->map_direct_value_meta(map, addr, off)) { 3528 *type = BPF_PSEUDO_MAP_VALUE; 3529 goto out; 3530 } 3531 } 3532 map = NULL; 3533 3534 out: 3535 mutex_unlock(&prog->aux->used_maps_mutex); 3536 return map; 3537 } 3538 3539 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 3540 const struct cred *f_cred) 3541 { 3542 const struct bpf_map *map; 3543 struct bpf_insn *insns; 3544 u32 off, type; 3545 u64 imm; 3546 u8 code; 3547 int i; 3548 3549 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 3550 GFP_USER); 3551 if (!insns) 3552 return insns; 3553 3554 for (i = 0; i < prog->len; i++) { 3555 code = insns[i].code; 3556 3557 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 3558 insns[i].code = BPF_JMP | BPF_CALL; 3559 insns[i].imm = BPF_FUNC_tail_call; 3560 /* fall-through */ 3561 } 3562 if (code == (BPF_JMP | BPF_CALL) || 3563 code == (BPF_JMP | BPF_CALL_ARGS)) { 3564 if (code == (BPF_JMP | BPF_CALL_ARGS)) 3565 insns[i].code = BPF_JMP | BPF_CALL; 3566 if (!bpf_dump_raw_ok(f_cred)) 3567 insns[i].imm = 0; 3568 continue; 3569 } 3570 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 3571 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 3572 continue; 3573 } 3574 3575 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 3576 continue; 3577 3578 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 3579 map = bpf_map_from_imm(prog, imm, &off, &type); 3580 if (map) { 3581 insns[i].src_reg = type; 3582 insns[i].imm = map->id; 3583 insns[i + 1].imm = off; 3584 continue; 3585 } 3586 } 3587 3588 return insns; 3589 } 3590 3591 static int set_info_rec_size(struct bpf_prog_info *info) 3592 { 3593 /* 3594 * Ensure info.*_rec_size is the same as kernel expected size 3595 * 3596 * or 3597 * 3598 * Only allow zero *_rec_size if both _rec_size and _cnt are 3599 * zero. In this case, the kernel will set the expected 3600 * _rec_size back to the info. 3601 */ 3602 3603 if ((info->nr_func_info || info->func_info_rec_size) && 3604 info->func_info_rec_size != sizeof(struct bpf_func_info)) 3605 return -EINVAL; 3606 3607 if ((info->nr_line_info || info->line_info_rec_size) && 3608 info->line_info_rec_size != sizeof(struct bpf_line_info)) 3609 return -EINVAL; 3610 3611 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 3612 info->jited_line_info_rec_size != sizeof(__u64)) 3613 return -EINVAL; 3614 3615 info->func_info_rec_size = sizeof(struct bpf_func_info); 3616 info->line_info_rec_size = sizeof(struct bpf_line_info); 3617 info->jited_line_info_rec_size = sizeof(__u64); 3618 3619 return 0; 3620 } 3621 3622 static int bpf_prog_get_info_by_fd(struct file *file, 3623 struct bpf_prog *prog, 3624 const union bpf_attr *attr, 3625 union bpf_attr __user *uattr) 3626 { 3627 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3628 struct bpf_prog_info info; 3629 u32 info_len = attr->info.info_len; 3630 struct bpf_prog_kstats stats; 3631 char __user *uinsns; 3632 u32 ulen; 3633 int err; 3634 3635 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3636 if (err) 3637 return err; 3638 info_len = min_t(u32, sizeof(info), info_len); 3639 3640 memset(&info, 0, sizeof(info)); 3641 if (copy_from_user(&info, uinfo, info_len)) 3642 return -EFAULT; 3643 3644 info.type = prog->type; 3645 info.id = prog->aux->id; 3646 info.load_time = prog->aux->load_time; 3647 info.created_by_uid = from_kuid_munged(current_user_ns(), 3648 prog->aux->user->uid); 3649 info.gpl_compatible = prog->gpl_compatible; 3650 3651 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3652 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3653 3654 mutex_lock(&prog->aux->used_maps_mutex); 3655 ulen = info.nr_map_ids; 3656 info.nr_map_ids = prog->aux->used_map_cnt; 3657 ulen = min_t(u32, info.nr_map_ids, ulen); 3658 if (ulen) { 3659 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3660 u32 i; 3661 3662 for (i = 0; i < ulen; i++) 3663 if (put_user(prog->aux->used_maps[i]->id, 3664 &user_map_ids[i])) { 3665 mutex_unlock(&prog->aux->used_maps_mutex); 3666 return -EFAULT; 3667 } 3668 } 3669 mutex_unlock(&prog->aux->used_maps_mutex); 3670 3671 err = set_info_rec_size(&info); 3672 if (err) 3673 return err; 3674 3675 bpf_prog_get_stats(prog, &stats); 3676 info.run_time_ns = stats.nsecs; 3677 info.run_cnt = stats.cnt; 3678 info.recursion_misses = stats.misses; 3679 3680 info.verified_insns = prog->aux->verified_insns; 3681 3682 if (!bpf_capable()) { 3683 info.jited_prog_len = 0; 3684 info.xlated_prog_len = 0; 3685 info.nr_jited_ksyms = 0; 3686 info.nr_jited_func_lens = 0; 3687 info.nr_func_info = 0; 3688 info.nr_line_info = 0; 3689 info.nr_jited_line_info = 0; 3690 goto done; 3691 } 3692 3693 ulen = info.xlated_prog_len; 3694 info.xlated_prog_len = bpf_prog_insn_size(prog); 3695 if (info.xlated_prog_len && ulen) { 3696 struct bpf_insn *insns_sanitized; 3697 bool fault; 3698 3699 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 3700 info.xlated_prog_insns = 0; 3701 goto done; 3702 } 3703 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 3704 if (!insns_sanitized) 3705 return -ENOMEM; 3706 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3707 ulen = min_t(u32, info.xlated_prog_len, ulen); 3708 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3709 kfree(insns_sanitized); 3710 if (fault) 3711 return -EFAULT; 3712 } 3713 3714 if (bpf_prog_is_dev_bound(prog->aux)) { 3715 err = bpf_prog_offload_info_fill(&info, prog); 3716 if (err) 3717 return err; 3718 goto done; 3719 } 3720 3721 /* NOTE: the following code is supposed to be skipped for offload. 3722 * bpf_prog_offload_info_fill() is the place to fill similar fields 3723 * for offload. 3724 */ 3725 ulen = info.jited_prog_len; 3726 if (prog->aux->func_cnt) { 3727 u32 i; 3728 3729 info.jited_prog_len = 0; 3730 for (i = 0; i < prog->aux->func_cnt; i++) 3731 info.jited_prog_len += prog->aux->func[i]->jited_len; 3732 } else { 3733 info.jited_prog_len = prog->jited_len; 3734 } 3735 3736 if (info.jited_prog_len && ulen) { 3737 if (bpf_dump_raw_ok(file->f_cred)) { 3738 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3739 ulen = min_t(u32, info.jited_prog_len, ulen); 3740 3741 /* for multi-function programs, copy the JITed 3742 * instructions for all the functions 3743 */ 3744 if (prog->aux->func_cnt) { 3745 u32 len, free, i; 3746 u8 *img; 3747 3748 free = ulen; 3749 for (i = 0; i < prog->aux->func_cnt; i++) { 3750 len = prog->aux->func[i]->jited_len; 3751 len = min_t(u32, len, free); 3752 img = (u8 *) prog->aux->func[i]->bpf_func; 3753 if (copy_to_user(uinsns, img, len)) 3754 return -EFAULT; 3755 uinsns += len; 3756 free -= len; 3757 if (!free) 3758 break; 3759 } 3760 } else { 3761 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3762 return -EFAULT; 3763 } 3764 } else { 3765 info.jited_prog_insns = 0; 3766 } 3767 } 3768 3769 ulen = info.nr_jited_ksyms; 3770 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3771 if (ulen) { 3772 if (bpf_dump_raw_ok(file->f_cred)) { 3773 unsigned long ksym_addr; 3774 u64 __user *user_ksyms; 3775 u32 i; 3776 3777 /* copy the address of the kernel symbol 3778 * corresponding to each function 3779 */ 3780 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3781 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3782 if (prog->aux->func_cnt) { 3783 for (i = 0; i < ulen; i++) { 3784 ksym_addr = (unsigned long) 3785 prog->aux->func[i]->bpf_func; 3786 if (put_user((u64) ksym_addr, 3787 &user_ksyms[i])) 3788 return -EFAULT; 3789 } 3790 } else { 3791 ksym_addr = (unsigned long) prog->bpf_func; 3792 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3793 return -EFAULT; 3794 } 3795 } else { 3796 info.jited_ksyms = 0; 3797 } 3798 } 3799 3800 ulen = info.nr_jited_func_lens; 3801 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3802 if (ulen) { 3803 if (bpf_dump_raw_ok(file->f_cred)) { 3804 u32 __user *user_lens; 3805 u32 func_len, i; 3806 3807 /* copy the JITed image lengths for each function */ 3808 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3809 user_lens = u64_to_user_ptr(info.jited_func_lens); 3810 if (prog->aux->func_cnt) { 3811 for (i = 0; i < ulen; i++) { 3812 func_len = 3813 prog->aux->func[i]->jited_len; 3814 if (put_user(func_len, &user_lens[i])) 3815 return -EFAULT; 3816 } 3817 } else { 3818 func_len = prog->jited_len; 3819 if (put_user(func_len, &user_lens[0])) 3820 return -EFAULT; 3821 } 3822 } else { 3823 info.jited_func_lens = 0; 3824 } 3825 } 3826 3827 if (prog->aux->btf) 3828 info.btf_id = btf_obj_id(prog->aux->btf); 3829 3830 ulen = info.nr_func_info; 3831 info.nr_func_info = prog->aux->func_info_cnt; 3832 if (info.nr_func_info && ulen) { 3833 char __user *user_finfo; 3834 3835 user_finfo = u64_to_user_ptr(info.func_info); 3836 ulen = min_t(u32, info.nr_func_info, ulen); 3837 if (copy_to_user(user_finfo, prog->aux->func_info, 3838 info.func_info_rec_size * ulen)) 3839 return -EFAULT; 3840 } 3841 3842 ulen = info.nr_line_info; 3843 info.nr_line_info = prog->aux->nr_linfo; 3844 if (info.nr_line_info && ulen) { 3845 __u8 __user *user_linfo; 3846 3847 user_linfo = u64_to_user_ptr(info.line_info); 3848 ulen = min_t(u32, info.nr_line_info, ulen); 3849 if (copy_to_user(user_linfo, prog->aux->linfo, 3850 info.line_info_rec_size * ulen)) 3851 return -EFAULT; 3852 } 3853 3854 ulen = info.nr_jited_line_info; 3855 if (prog->aux->jited_linfo) 3856 info.nr_jited_line_info = prog->aux->nr_linfo; 3857 else 3858 info.nr_jited_line_info = 0; 3859 if (info.nr_jited_line_info && ulen) { 3860 if (bpf_dump_raw_ok(file->f_cred)) { 3861 __u64 __user *user_linfo; 3862 u32 i; 3863 3864 user_linfo = u64_to_user_ptr(info.jited_line_info); 3865 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3866 for (i = 0; i < ulen; i++) { 3867 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3868 &user_linfo[i])) 3869 return -EFAULT; 3870 } 3871 } else { 3872 info.jited_line_info = 0; 3873 } 3874 } 3875 3876 ulen = info.nr_prog_tags; 3877 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3878 if (ulen) { 3879 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3880 u32 i; 3881 3882 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3883 ulen = min_t(u32, info.nr_prog_tags, ulen); 3884 if (prog->aux->func_cnt) { 3885 for (i = 0; i < ulen; i++) { 3886 if (copy_to_user(user_prog_tags[i], 3887 prog->aux->func[i]->tag, 3888 BPF_TAG_SIZE)) 3889 return -EFAULT; 3890 } 3891 } else { 3892 if (copy_to_user(user_prog_tags[0], 3893 prog->tag, BPF_TAG_SIZE)) 3894 return -EFAULT; 3895 } 3896 } 3897 3898 done: 3899 if (copy_to_user(uinfo, &info, info_len) || 3900 put_user(info_len, &uattr->info.info_len)) 3901 return -EFAULT; 3902 3903 return 0; 3904 } 3905 3906 static int bpf_map_get_info_by_fd(struct file *file, 3907 struct bpf_map *map, 3908 const union bpf_attr *attr, 3909 union bpf_attr __user *uattr) 3910 { 3911 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3912 struct bpf_map_info info; 3913 u32 info_len = attr->info.info_len; 3914 int err; 3915 3916 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3917 if (err) 3918 return err; 3919 info_len = min_t(u32, sizeof(info), info_len); 3920 3921 memset(&info, 0, sizeof(info)); 3922 info.type = map->map_type; 3923 info.id = map->id; 3924 info.key_size = map->key_size; 3925 info.value_size = map->value_size; 3926 info.max_entries = map->max_entries; 3927 info.map_flags = map->map_flags; 3928 info.map_extra = map->map_extra; 3929 memcpy(info.name, map->name, sizeof(map->name)); 3930 3931 if (map->btf) { 3932 info.btf_id = btf_obj_id(map->btf); 3933 info.btf_key_type_id = map->btf_key_type_id; 3934 info.btf_value_type_id = map->btf_value_type_id; 3935 } 3936 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3937 3938 if (bpf_map_is_dev_bound(map)) { 3939 err = bpf_map_offload_info_fill(&info, map); 3940 if (err) 3941 return err; 3942 } 3943 3944 if (copy_to_user(uinfo, &info, info_len) || 3945 put_user(info_len, &uattr->info.info_len)) 3946 return -EFAULT; 3947 3948 return 0; 3949 } 3950 3951 static int bpf_btf_get_info_by_fd(struct file *file, 3952 struct btf *btf, 3953 const union bpf_attr *attr, 3954 union bpf_attr __user *uattr) 3955 { 3956 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3957 u32 info_len = attr->info.info_len; 3958 int err; 3959 3960 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 3961 if (err) 3962 return err; 3963 3964 return btf_get_info_by_fd(btf, attr, uattr); 3965 } 3966 3967 static int bpf_link_get_info_by_fd(struct file *file, 3968 struct bpf_link *link, 3969 const union bpf_attr *attr, 3970 union bpf_attr __user *uattr) 3971 { 3972 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3973 struct bpf_link_info info; 3974 u32 info_len = attr->info.info_len; 3975 int err; 3976 3977 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 3978 if (err) 3979 return err; 3980 info_len = min_t(u32, sizeof(info), info_len); 3981 3982 memset(&info, 0, sizeof(info)); 3983 if (copy_from_user(&info, uinfo, info_len)) 3984 return -EFAULT; 3985 3986 info.type = link->type; 3987 info.id = link->id; 3988 info.prog_id = link->prog->aux->id; 3989 3990 if (link->ops->fill_link_info) { 3991 err = link->ops->fill_link_info(link, &info); 3992 if (err) 3993 return err; 3994 } 3995 3996 if (copy_to_user(uinfo, &info, info_len) || 3997 put_user(info_len, &uattr->info.info_len)) 3998 return -EFAULT; 3999 4000 return 0; 4001 } 4002 4003 4004 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 4005 4006 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 4007 union bpf_attr __user *uattr) 4008 { 4009 int ufd = attr->info.bpf_fd; 4010 struct fd f; 4011 int err; 4012 4013 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4014 return -EINVAL; 4015 4016 f = fdget(ufd); 4017 if (!f.file) 4018 return -EBADFD; 4019 4020 if (f.file->f_op == &bpf_prog_fops) 4021 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr, 4022 uattr); 4023 else if (f.file->f_op == &bpf_map_fops) 4024 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr, 4025 uattr); 4026 else if (f.file->f_op == &btf_fops) 4027 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr); 4028 else if (f.file->f_op == &bpf_link_fops) 4029 err = bpf_link_get_info_by_fd(f.file, f.file->private_data, 4030 attr, uattr); 4031 else 4032 err = -EINVAL; 4033 4034 fdput(f); 4035 return err; 4036 } 4037 4038 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 4039 4040 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr) 4041 { 4042 if (CHECK_ATTR(BPF_BTF_LOAD)) 4043 return -EINVAL; 4044 4045 if (!bpf_capable()) 4046 return -EPERM; 4047 4048 return btf_new_fd(attr, uattr); 4049 } 4050 4051 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4052 4053 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4054 { 4055 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4056 return -EINVAL; 4057 4058 if (!capable(CAP_SYS_ADMIN)) 4059 return -EPERM; 4060 4061 return btf_get_fd_by_id(attr->btf_id); 4062 } 4063 4064 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 4065 union bpf_attr __user *uattr, 4066 u32 prog_id, u32 fd_type, 4067 const char *buf, u64 probe_offset, 4068 u64 probe_addr) 4069 { 4070 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 4071 u32 len = buf ? strlen(buf) : 0, input_len; 4072 int err = 0; 4073 4074 if (put_user(len, &uattr->task_fd_query.buf_len)) 4075 return -EFAULT; 4076 input_len = attr->task_fd_query.buf_len; 4077 if (input_len && ubuf) { 4078 if (!len) { 4079 /* nothing to copy, just make ubuf NULL terminated */ 4080 char zero = '\0'; 4081 4082 if (put_user(zero, ubuf)) 4083 return -EFAULT; 4084 } else if (input_len >= len + 1) { 4085 /* ubuf can hold the string with NULL terminator */ 4086 if (copy_to_user(ubuf, buf, len + 1)) 4087 return -EFAULT; 4088 } else { 4089 /* ubuf cannot hold the string with NULL terminator, 4090 * do a partial copy with NULL terminator. 4091 */ 4092 char zero = '\0'; 4093 4094 err = -ENOSPC; 4095 if (copy_to_user(ubuf, buf, input_len - 1)) 4096 return -EFAULT; 4097 if (put_user(zero, ubuf + input_len - 1)) 4098 return -EFAULT; 4099 } 4100 } 4101 4102 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 4103 put_user(fd_type, &uattr->task_fd_query.fd_type) || 4104 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 4105 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 4106 return -EFAULT; 4107 4108 return err; 4109 } 4110 4111 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 4112 4113 static int bpf_task_fd_query(const union bpf_attr *attr, 4114 union bpf_attr __user *uattr) 4115 { 4116 pid_t pid = attr->task_fd_query.pid; 4117 u32 fd = attr->task_fd_query.fd; 4118 const struct perf_event *event; 4119 struct task_struct *task; 4120 struct file *file; 4121 int err; 4122 4123 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 4124 return -EINVAL; 4125 4126 if (!capable(CAP_SYS_ADMIN)) 4127 return -EPERM; 4128 4129 if (attr->task_fd_query.flags != 0) 4130 return -EINVAL; 4131 4132 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 4133 if (!task) 4134 return -ENOENT; 4135 4136 err = 0; 4137 file = fget_task(task, fd); 4138 put_task_struct(task); 4139 if (!file) 4140 return -EBADF; 4141 4142 if (file->f_op == &bpf_link_fops) { 4143 struct bpf_link *link = file->private_data; 4144 4145 if (link->ops == &bpf_raw_tp_link_lops) { 4146 struct bpf_raw_tp_link *raw_tp = 4147 container_of(link, struct bpf_raw_tp_link, link); 4148 struct bpf_raw_event_map *btp = raw_tp->btp; 4149 4150 err = bpf_task_fd_query_copy(attr, uattr, 4151 raw_tp->link.prog->aux->id, 4152 BPF_FD_TYPE_RAW_TRACEPOINT, 4153 btp->tp->name, 0, 0); 4154 goto put_file; 4155 } 4156 goto out_not_supp; 4157 } 4158 4159 event = perf_get_event(file); 4160 if (!IS_ERR(event)) { 4161 u64 probe_offset, probe_addr; 4162 u32 prog_id, fd_type; 4163 const char *buf; 4164 4165 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 4166 &buf, &probe_offset, 4167 &probe_addr); 4168 if (!err) 4169 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 4170 fd_type, buf, 4171 probe_offset, 4172 probe_addr); 4173 goto put_file; 4174 } 4175 4176 out_not_supp: 4177 err = -ENOTSUPP; 4178 put_file: 4179 fput(file); 4180 return err; 4181 } 4182 4183 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 4184 4185 #define BPF_DO_BATCH(fn) \ 4186 do { \ 4187 if (!fn) { \ 4188 err = -ENOTSUPP; \ 4189 goto err_put; \ 4190 } \ 4191 err = fn(map, attr, uattr); \ 4192 } while (0) 4193 4194 static int bpf_map_do_batch(const union bpf_attr *attr, 4195 union bpf_attr __user *uattr, 4196 int cmd) 4197 { 4198 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 4199 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 4200 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 4201 struct bpf_map *map; 4202 int err, ufd; 4203 struct fd f; 4204 4205 if (CHECK_ATTR(BPF_MAP_BATCH)) 4206 return -EINVAL; 4207 4208 ufd = attr->batch.map_fd; 4209 f = fdget(ufd); 4210 map = __bpf_map_get(f); 4211 if (IS_ERR(map)) 4212 return PTR_ERR(map); 4213 if (has_write) 4214 bpf_map_write_active_inc(map); 4215 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 4216 err = -EPERM; 4217 goto err_put; 4218 } 4219 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 4220 err = -EPERM; 4221 goto err_put; 4222 } 4223 4224 if (cmd == BPF_MAP_LOOKUP_BATCH) 4225 BPF_DO_BATCH(map->ops->map_lookup_batch); 4226 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 4227 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 4228 else if (cmd == BPF_MAP_UPDATE_BATCH) 4229 BPF_DO_BATCH(map->ops->map_update_batch); 4230 else 4231 BPF_DO_BATCH(map->ops->map_delete_batch); 4232 err_put: 4233 if (has_write) 4234 bpf_map_write_active_dec(map); 4235 fdput(f); 4236 return err; 4237 } 4238 4239 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, 4240 struct bpf_prog *prog) 4241 { 4242 if (attr->link_create.attach_type != prog->expected_attach_type) 4243 return -EINVAL; 4244 4245 if (prog->expected_attach_type == BPF_TRACE_ITER) 4246 return bpf_iter_link_attach(attr, uattr, prog); 4247 else if (prog->type == BPF_PROG_TYPE_EXT) 4248 return bpf_tracing_prog_attach(prog, 4249 attr->link_create.target_fd, 4250 attr->link_create.target_btf_id); 4251 return -EINVAL; 4252 } 4253 4254 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len 4255 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 4256 { 4257 enum bpf_prog_type ptype; 4258 struct bpf_prog *prog; 4259 int ret; 4260 4261 if (CHECK_ATTR(BPF_LINK_CREATE)) 4262 return -EINVAL; 4263 4264 prog = bpf_prog_get(attr->link_create.prog_fd); 4265 if (IS_ERR(prog)) 4266 return PTR_ERR(prog); 4267 4268 ret = bpf_prog_attach_check_attach_type(prog, 4269 attr->link_create.attach_type); 4270 if (ret) 4271 goto out; 4272 4273 switch (prog->type) { 4274 case BPF_PROG_TYPE_EXT: 4275 ret = tracing_bpf_link_attach(attr, uattr, prog); 4276 goto out; 4277 case BPF_PROG_TYPE_PERF_EVENT: 4278 case BPF_PROG_TYPE_KPROBE: 4279 case BPF_PROG_TYPE_TRACEPOINT: 4280 if (attr->link_create.attach_type != BPF_PERF_EVENT) { 4281 ret = -EINVAL; 4282 goto out; 4283 } 4284 ptype = prog->type; 4285 break; 4286 default: 4287 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 4288 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) { 4289 ret = -EINVAL; 4290 goto out; 4291 } 4292 break; 4293 } 4294 4295 switch (ptype) { 4296 case BPF_PROG_TYPE_CGROUP_SKB: 4297 case BPF_PROG_TYPE_CGROUP_SOCK: 4298 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4299 case BPF_PROG_TYPE_SOCK_OPS: 4300 case BPF_PROG_TYPE_CGROUP_DEVICE: 4301 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4302 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4303 ret = cgroup_bpf_link_attach(attr, prog); 4304 break; 4305 case BPF_PROG_TYPE_TRACING: 4306 ret = tracing_bpf_link_attach(attr, uattr, prog); 4307 break; 4308 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4309 case BPF_PROG_TYPE_SK_LOOKUP: 4310 ret = netns_bpf_link_create(attr, prog); 4311 break; 4312 #ifdef CONFIG_NET 4313 case BPF_PROG_TYPE_XDP: 4314 ret = bpf_xdp_link_attach(attr, prog); 4315 break; 4316 #endif 4317 #ifdef CONFIG_PERF_EVENTS 4318 case BPF_PROG_TYPE_PERF_EVENT: 4319 case BPF_PROG_TYPE_TRACEPOINT: 4320 case BPF_PROG_TYPE_KPROBE: 4321 ret = bpf_perf_link_attach(attr, prog); 4322 break; 4323 #endif 4324 default: 4325 ret = -EINVAL; 4326 } 4327 4328 out: 4329 if (ret < 0) 4330 bpf_prog_put(prog); 4331 return ret; 4332 } 4333 4334 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 4335 4336 static int link_update(union bpf_attr *attr) 4337 { 4338 struct bpf_prog *old_prog = NULL, *new_prog; 4339 struct bpf_link *link; 4340 u32 flags; 4341 int ret; 4342 4343 if (CHECK_ATTR(BPF_LINK_UPDATE)) 4344 return -EINVAL; 4345 4346 flags = attr->link_update.flags; 4347 if (flags & ~BPF_F_REPLACE) 4348 return -EINVAL; 4349 4350 link = bpf_link_get_from_fd(attr->link_update.link_fd); 4351 if (IS_ERR(link)) 4352 return PTR_ERR(link); 4353 4354 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 4355 if (IS_ERR(new_prog)) { 4356 ret = PTR_ERR(new_prog); 4357 goto out_put_link; 4358 } 4359 4360 if (flags & BPF_F_REPLACE) { 4361 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 4362 if (IS_ERR(old_prog)) { 4363 ret = PTR_ERR(old_prog); 4364 old_prog = NULL; 4365 goto out_put_progs; 4366 } 4367 } else if (attr->link_update.old_prog_fd) { 4368 ret = -EINVAL; 4369 goto out_put_progs; 4370 } 4371 4372 if (link->ops->update_prog) 4373 ret = link->ops->update_prog(link, new_prog, old_prog); 4374 else 4375 ret = -EINVAL; 4376 4377 out_put_progs: 4378 if (old_prog) 4379 bpf_prog_put(old_prog); 4380 if (ret) 4381 bpf_prog_put(new_prog); 4382 out_put_link: 4383 bpf_link_put(link); 4384 return ret; 4385 } 4386 4387 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 4388 4389 static int link_detach(union bpf_attr *attr) 4390 { 4391 struct bpf_link *link; 4392 int ret; 4393 4394 if (CHECK_ATTR(BPF_LINK_DETACH)) 4395 return -EINVAL; 4396 4397 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 4398 if (IS_ERR(link)) 4399 return PTR_ERR(link); 4400 4401 if (link->ops->detach) 4402 ret = link->ops->detach(link); 4403 else 4404 ret = -EOPNOTSUPP; 4405 4406 bpf_link_put(link); 4407 return ret; 4408 } 4409 4410 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 4411 { 4412 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 4413 } 4414 4415 struct bpf_link *bpf_link_by_id(u32 id) 4416 { 4417 struct bpf_link *link; 4418 4419 if (!id) 4420 return ERR_PTR(-ENOENT); 4421 4422 spin_lock_bh(&link_idr_lock); 4423 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 4424 link = idr_find(&link_idr, id); 4425 if (link) { 4426 if (link->id) 4427 link = bpf_link_inc_not_zero(link); 4428 else 4429 link = ERR_PTR(-EAGAIN); 4430 } else { 4431 link = ERR_PTR(-ENOENT); 4432 } 4433 spin_unlock_bh(&link_idr_lock); 4434 return link; 4435 } 4436 4437 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 4438 4439 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 4440 { 4441 struct bpf_link *link; 4442 u32 id = attr->link_id; 4443 int fd; 4444 4445 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 4446 return -EINVAL; 4447 4448 if (!capable(CAP_SYS_ADMIN)) 4449 return -EPERM; 4450 4451 link = bpf_link_by_id(id); 4452 if (IS_ERR(link)) 4453 return PTR_ERR(link); 4454 4455 fd = bpf_link_new_fd(link); 4456 if (fd < 0) 4457 bpf_link_put(link); 4458 4459 return fd; 4460 } 4461 4462 DEFINE_MUTEX(bpf_stats_enabled_mutex); 4463 4464 static int bpf_stats_release(struct inode *inode, struct file *file) 4465 { 4466 mutex_lock(&bpf_stats_enabled_mutex); 4467 static_key_slow_dec(&bpf_stats_enabled_key.key); 4468 mutex_unlock(&bpf_stats_enabled_mutex); 4469 return 0; 4470 } 4471 4472 static const struct file_operations bpf_stats_fops = { 4473 .release = bpf_stats_release, 4474 }; 4475 4476 static int bpf_enable_runtime_stats(void) 4477 { 4478 int fd; 4479 4480 mutex_lock(&bpf_stats_enabled_mutex); 4481 4482 /* Set a very high limit to avoid overflow */ 4483 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 4484 mutex_unlock(&bpf_stats_enabled_mutex); 4485 return -EBUSY; 4486 } 4487 4488 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 4489 if (fd >= 0) 4490 static_key_slow_inc(&bpf_stats_enabled_key.key); 4491 4492 mutex_unlock(&bpf_stats_enabled_mutex); 4493 return fd; 4494 } 4495 4496 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 4497 4498 static int bpf_enable_stats(union bpf_attr *attr) 4499 { 4500 4501 if (CHECK_ATTR(BPF_ENABLE_STATS)) 4502 return -EINVAL; 4503 4504 if (!capable(CAP_SYS_ADMIN)) 4505 return -EPERM; 4506 4507 switch (attr->enable_stats.type) { 4508 case BPF_STATS_RUN_TIME: 4509 return bpf_enable_runtime_stats(); 4510 default: 4511 break; 4512 } 4513 return -EINVAL; 4514 } 4515 4516 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 4517 4518 static int bpf_iter_create(union bpf_attr *attr) 4519 { 4520 struct bpf_link *link; 4521 int err; 4522 4523 if (CHECK_ATTR(BPF_ITER_CREATE)) 4524 return -EINVAL; 4525 4526 if (attr->iter_create.flags) 4527 return -EINVAL; 4528 4529 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 4530 if (IS_ERR(link)) 4531 return PTR_ERR(link); 4532 4533 err = bpf_iter_new_fd(link); 4534 bpf_link_put(link); 4535 4536 return err; 4537 } 4538 4539 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 4540 4541 static int bpf_prog_bind_map(union bpf_attr *attr) 4542 { 4543 struct bpf_prog *prog; 4544 struct bpf_map *map; 4545 struct bpf_map **used_maps_old, **used_maps_new; 4546 int i, ret = 0; 4547 4548 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 4549 return -EINVAL; 4550 4551 if (attr->prog_bind_map.flags) 4552 return -EINVAL; 4553 4554 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 4555 if (IS_ERR(prog)) 4556 return PTR_ERR(prog); 4557 4558 map = bpf_map_get(attr->prog_bind_map.map_fd); 4559 if (IS_ERR(map)) { 4560 ret = PTR_ERR(map); 4561 goto out_prog_put; 4562 } 4563 4564 mutex_lock(&prog->aux->used_maps_mutex); 4565 4566 used_maps_old = prog->aux->used_maps; 4567 4568 for (i = 0; i < prog->aux->used_map_cnt; i++) 4569 if (used_maps_old[i] == map) { 4570 bpf_map_put(map); 4571 goto out_unlock; 4572 } 4573 4574 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 4575 sizeof(used_maps_new[0]), 4576 GFP_KERNEL); 4577 if (!used_maps_new) { 4578 ret = -ENOMEM; 4579 goto out_unlock; 4580 } 4581 4582 memcpy(used_maps_new, used_maps_old, 4583 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 4584 used_maps_new[prog->aux->used_map_cnt] = map; 4585 4586 prog->aux->used_map_cnt++; 4587 prog->aux->used_maps = used_maps_new; 4588 4589 kfree(used_maps_old); 4590 4591 out_unlock: 4592 mutex_unlock(&prog->aux->used_maps_mutex); 4593 4594 if (ret) 4595 bpf_map_put(map); 4596 out_prog_put: 4597 bpf_prog_put(prog); 4598 return ret; 4599 } 4600 4601 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) 4602 { 4603 union bpf_attr attr; 4604 int err; 4605 4606 if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) 4607 return -EPERM; 4608 4609 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 4610 if (err) 4611 return err; 4612 size = min_t(u32, size, sizeof(attr)); 4613 4614 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 4615 memset(&attr, 0, sizeof(attr)); 4616 if (copy_from_bpfptr(&attr, uattr, size) != 0) 4617 return -EFAULT; 4618 4619 err = security_bpf(cmd, &attr, size); 4620 if (err < 0) 4621 return err; 4622 4623 switch (cmd) { 4624 case BPF_MAP_CREATE: 4625 err = map_create(&attr); 4626 break; 4627 case BPF_MAP_LOOKUP_ELEM: 4628 err = map_lookup_elem(&attr); 4629 break; 4630 case BPF_MAP_UPDATE_ELEM: 4631 err = map_update_elem(&attr, uattr); 4632 break; 4633 case BPF_MAP_DELETE_ELEM: 4634 err = map_delete_elem(&attr); 4635 break; 4636 case BPF_MAP_GET_NEXT_KEY: 4637 err = map_get_next_key(&attr); 4638 break; 4639 case BPF_MAP_FREEZE: 4640 err = map_freeze(&attr); 4641 break; 4642 case BPF_PROG_LOAD: 4643 err = bpf_prog_load(&attr, uattr); 4644 break; 4645 case BPF_OBJ_PIN: 4646 err = bpf_obj_pin(&attr); 4647 break; 4648 case BPF_OBJ_GET: 4649 err = bpf_obj_get(&attr); 4650 break; 4651 case BPF_PROG_ATTACH: 4652 err = bpf_prog_attach(&attr); 4653 break; 4654 case BPF_PROG_DETACH: 4655 err = bpf_prog_detach(&attr); 4656 break; 4657 case BPF_PROG_QUERY: 4658 err = bpf_prog_query(&attr, uattr.user); 4659 break; 4660 case BPF_PROG_TEST_RUN: 4661 err = bpf_prog_test_run(&attr, uattr.user); 4662 break; 4663 case BPF_PROG_GET_NEXT_ID: 4664 err = bpf_obj_get_next_id(&attr, uattr.user, 4665 &prog_idr, &prog_idr_lock); 4666 break; 4667 case BPF_MAP_GET_NEXT_ID: 4668 err = bpf_obj_get_next_id(&attr, uattr.user, 4669 &map_idr, &map_idr_lock); 4670 break; 4671 case BPF_BTF_GET_NEXT_ID: 4672 err = bpf_obj_get_next_id(&attr, uattr.user, 4673 &btf_idr, &btf_idr_lock); 4674 break; 4675 case BPF_PROG_GET_FD_BY_ID: 4676 err = bpf_prog_get_fd_by_id(&attr); 4677 break; 4678 case BPF_MAP_GET_FD_BY_ID: 4679 err = bpf_map_get_fd_by_id(&attr); 4680 break; 4681 case BPF_OBJ_GET_INFO_BY_FD: 4682 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 4683 break; 4684 case BPF_RAW_TRACEPOINT_OPEN: 4685 err = bpf_raw_tracepoint_open(&attr); 4686 break; 4687 case BPF_BTF_LOAD: 4688 err = bpf_btf_load(&attr, uattr); 4689 break; 4690 case BPF_BTF_GET_FD_BY_ID: 4691 err = bpf_btf_get_fd_by_id(&attr); 4692 break; 4693 case BPF_TASK_FD_QUERY: 4694 err = bpf_task_fd_query(&attr, uattr.user); 4695 break; 4696 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 4697 err = map_lookup_and_delete_elem(&attr); 4698 break; 4699 case BPF_MAP_LOOKUP_BATCH: 4700 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 4701 break; 4702 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 4703 err = bpf_map_do_batch(&attr, uattr.user, 4704 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 4705 break; 4706 case BPF_MAP_UPDATE_BATCH: 4707 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 4708 break; 4709 case BPF_MAP_DELETE_BATCH: 4710 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 4711 break; 4712 case BPF_LINK_CREATE: 4713 err = link_create(&attr, uattr); 4714 break; 4715 case BPF_LINK_UPDATE: 4716 err = link_update(&attr); 4717 break; 4718 case BPF_LINK_GET_FD_BY_ID: 4719 err = bpf_link_get_fd_by_id(&attr); 4720 break; 4721 case BPF_LINK_GET_NEXT_ID: 4722 err = bpf_obj_get_next_id(&attr, uattr.user, 4723 &link_idr, &link_idr_lock); 4724 break; 4725 case BPF_ENABLE_STATS: 4726 err = bpf_enable_stats(&attr); 4727 break; 4728 case BPF_ITER_CREATE: 4729 err = bpf_iter_create(&attr); 4730 break; 4731 case BPF_LINK_DETACH: 4732 err = link_detach(&attr); 4733 break; 4734 case BPF_PROG_BIND_MAP: 4735 err = bpf_prog_bind_map(&attr); 4736 break; 4737 default: 4738 err = -EINVAL; 4739 break; 4740 } 4741 4742 return err; 4743 } 4744 4745 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 4746 { 4747 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 4748 } 4749 4750 static bool syscall_prog_is_valid_access(int off, int size, 4751 enum bpf_access_type type, 4752 const struct bpf_prog *prog, 4753 struct bpf_insn_access_aux *info) 4754 { 4755 if (off < 0 || off >= U16_MAX) 4756 return false; 4757 if (off % size != 0) 4758 return false; 4759 return true; 4760 } 4761 4762 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 4763 { 4764 struct bpf_prog * __maybe_unused prog; 4765 4766 switch (cmd) { 4767 case BPF_MAP_CREATE: 4768 case BPF_MAP_UPDATE_ELEM: 4769 case BPF_MAP_FREEZE: 4770 case BPF_PROG_LOAD: 4771 case BPF_BTF_LOAD: 4772 case BPF_LINK_CREATE: 4773 case BPF_RAW_TRACEPOINT_OPEN: 4774 break; 4775 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 4776 case BPF_PROG_TEST_RUN: 4777 if (attr->test.data_in || attr->test.data_out || 4778 attr->test.ctx_out || attr->test.duration || 4779 attr->test.repeat || attr->test.flags) 4780 return -EINVAL; 4781 4782 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 4783 if (IS_ERR(prog)) 4784 return PTR_ERR(prog); 4785 4786 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 4787 attr->test.ctx_size_in > U16_MAX) { 4788 bpf_prog_put(prog); 4789 return -EINVAL; 4790 } 4791 4792 if (!__bpf_prog_enter_sleepable(prog)) { 4793 /* recursion detected */ 4794 bpf_prog_put(prog); 4795 return -EBUSY; 4796 } 4797 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 4798 __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */); 4799 bpf_prog_put(prog); 4800 return 0; 4801 #endif 4802 default: 4803 return -EINVAL; 4804 } 4805 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 4806 } 4807 EXPORT_SYMBOL(bpf_sys_bpf); 4808 4809 static const struct bpf_func_proto bpf_sys_bpf_proto = { 4810 .func = bpf_sys_bpf, 4811 .gpl_only = false, 4812 .ret_type = RET_INTEGER, 4813 .arg1_type = ARG_ANYTHING, 4814 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 4815 .arg3_type = ARG_CONST_SIZE, 4816 }; 4817 4818 const struct bpf_func_proto * __weak 4819 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4820 { 4821 return bpf_base_func_proto(func_id); 4822 } 4823 4824 BPF_CALL_1(bpf_sys_close, u32, fd) 4825 { 4826 /* When bpf program calls this helper there should not be 4827 * an fdget() without matching completed fdput(). 4828 * This helper is allowed in the following callchain only: 4829 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 4830 */ 4831 return close_fd(fd); 4832 } 4833 4834 static const struct bpf_func_proto bpf_sys_close_proto = { 4835 .func = bpf_sys_close, 4836 .gpl_only = false, 4837 .ret_type = RET_INTEGER, 4838 .arg1_type = ARG_ANYTHING, 4839 }; 4840 4841 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 4842 { 4843 if (flags) 4844 return -EINVAL; 4845 4846 if (name_sz <= 1 || name[name_sz - 1]) 4847 return -EINVAL; 4848 4849 if (!bpf_dump_raw_ok(current_cred())) 4850 return -EPERM; 4851 4852 *res = kallsyms_lookup_name(name); 4853 return *res ? 0 : -ENOENT; 4854 } 4855 4856 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 4857 .func = bpf_kallsyms_lookup_name, 4858 .gpl_only = false, 4859 .ret_type = RET_INTEGER, 4860 .arg1_type = ARG_PTR_TO_MEM, 4861 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 4862 .arg3_type = ARG_ANYTHING, 4863 .arg4_type = ARG_PTR_TO_LONG, 4864 }; 4865 4866 static const struct bpf_func_proto * 4867 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4868 { 4869 switch (func_id) { 4870 case BPF_FUNC_sys_bpf: 4871 return &bpf_sys_bpf_proto; 4872 case BPF_FUNC_btf_find_by_name_kind: 4873 return &bpf_btf_find_by_name_kind_proto; 4874 case BPF_FUNC_sys_close: 4875 return &bpf_sys_close_proto; 4876 case BPF_FUNC_kallsyms_lookup_name: 4877 return &bpf_kallsyms_lookup_name_proto; 4878 default: 4879 return tracing_prog_func_proto(func_id, prog); 4880 } 4881 } 4882 4883 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 4884 .get_func_proto = syscall_prog_func_proto, 4885 .is_valid_access = syscall_prog_is_valid_access, 4886 }; 4887 4888 const struct bpf_prog_ops bpf_syscall_prog_ops = { 4889 .test_run = bpf_prog_test_run_syscall, 4890 }; 4891