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