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