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