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