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/btf.h> 8 #include <linux/syscalls.h> 9 #include <linux/slab.h> 10 #include <linux/sched/signal.h> 11 #include <linux/vmalloc.h> 12 #include <linux/mmzone.h> 13 #include <linux/anon_inodes.h> 14 #include <linux/fdtable.h> 15 #include <linux/file.h> 16 #include <linux/fs.h> 17 #include <linux/license.h> 18 #include <linux/filter.h> 19 #include <linux/version.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/bpf_lsm.h> 29 30 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 31 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 32 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 33 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 34 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 35 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 36 IS_FD_HASH(map)) 37 38 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 39 40 DEFINE_PER_CPU(int, bpf_prog_active); 41 static DEFINE_IDR(prog_idr); 42 static DEFINE_SPINLOCK(prog_idr_lock); 43 static DEFINE_IDR(map_idr); 44 static DEFINE_SPINLOCK(map_idr_lock); 45 46 int sysctl_unprivileged_bpf_disabled __read_mostly; 47 48 static const struct bpf_map_ops * const bpf_map_types[] = { 49 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 50 #define BPF_MAP_TYPE(_id, _ops) \ 51 [_id] = &_ops, 52 #include <linux/bpf_types.h> 53 #undef BPF_PROG_TYPE 54 #undef BPF_MAP_TYPE 55 }; 56 57 /* 58 * If we're handed a bigger struct than we know of, ensure all the unknown bits 59 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 60 * we don't know about yet. 61 * 62 * There is a ToCToU between this function call and the following 63 * copy_from_user() call. However, this is not a concern since this function is 64 * meant to be a future-proofing of bits. 65 */ 66 int bpf_check_uarg_tail_zero(void __user *uaddr, 67 size_t expected_size, 68 size_t actual_size) 69 { 70 unsigned char __user *addr; 71 unsigned char __user *end; 72 unsigned char val; 73 int err; 74 75 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 76 return -E2BIG; 77 78 if (unlikely(!access_ok(uaddr, actual_size))) 79 return -EFAULT; 80 81 if (actual_size <= expected_size) 82 return 0; 83 84 addr = uaddr + expected_size; 85 end = uaddr + actual_size; 86 87 for (; addr < end; addr++) { 88 err = get_user(val, addr); 89 if (err) 90 return err; 91 if (val) 92 return -E2BIG; 93 } 94 95 return 0; 96 } 97 98 const struct bpf_map_ops bpf_map_offload_ops = { 99 .map_alloc = bpf_map_offload_map_alloc, 100 .map_free = bpf_map_offload_map_free, 101 .map_check_btf = map_check_no_btf, 102 }; 103 104 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 105 { 106 const struct bpf_map_ops *ops; 107 u32 type = attr->map_type; 108 struct bpf_map *map; 109 int err; 110 111 if (type >= ARRAY_SIZE(bpf_map_types)) 112 return ERR_PTR(-EINVAL); 113 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 114 ops = bpf_map_types[type]; 115 if (!ops) 116 return ERR_PTR(-EINVAL); 117 118 if (ops->map_alloc_check) { 119 err = ops->map_alloc_check(attr); 120 if (err) 121 return ERR_PTR(err); 122 } 123 if (attr->map_ifindex) 124 ops = &bpf_map_offload_ops; 125 map = ops->map_alloc(attr); 126 if (IS_ERR(map)) 127 return map; 128 map->ops = ops; 129 map->map_type = type; 130 return map; 131 } 132 133 static u32 bpf_map_value_size(struct bpf_map *map) 134 { 135 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 136 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 137 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 138 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 139 return round_up(map->value_size, 8) * num_possible_cpus(); 140 else if (IS_FD_MAP(map)) 141 return sizeof(u32); 142 else 143 return map->value_size; 144 } 145 146 static void maybe_wait_bpf_programs(struct bpf_map *map) 147 { 148 /* Wait for any running BPF programs to complete so that 149 * userspace, when we return to it, knows that all programs 150 * that could be running use the new map value. 151 */ 152 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 153 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 154 synchronize_rcu(); 155 } 156 157 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 158 void *value, __u64 flags) 159 { 160 int err; 161 162 /* Need to create a kthread, thus must support schedule */ 163 if (bpf_map_is_dev_bound(map)) { 164 return bpf_map_offload_update_elem(map, key, value, flags); 165 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 166 map->map_type == BPF_MAP_TYPE_SOCKHASH || 167 map->map_type == BPF_MAP_TYPE_SOCKMAP || 168 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 169 return map->ops->map_update_elem(map, key, value, flags); 170 } else if (IS_FD_PROG_ARRAY(map)) { 171 return bpf_fd_array_map_update_elem(map, f.file, key, value, 172 flags); 173 } 174 175 bpf_disable_instrumentation(); 176 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 177 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 178 err = bpf_percpu_hash_update(map, key, value, flags); 179 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 180 err = bpf_percpu_array_update(map, key, value, flags); 181 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 182 err = bpf_percpu_cgroup_storage_update(map, key, value, 183 flags); 184 } else if (IS_FD_ARRAY(map)) { 185 rcu_read_lock(); 186 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 187 flags); 188 rcu_read_unlock(); 189 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 190 rcu_read_lock(); 191 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 192 flags); 193 rcu_read_unlock(); 194 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 195 /* rcu_read_lock() is not needed */ 196 err = bpf_fd_reuseport_array_update_elem(map, key, value, 197 flags); 198 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 199 map->map_type == BPF_MAP_TYPE_STACK) { 200 err = map->ops->map_push_elem(map, value, flags); 201 } else { 202 rcu_read_lock(); 203 err = map->ops->map_update_elem(map, key, value, flags); 204 rcu_read_unlock(); 205 } 206 bpf_enable_instrumentation(); 207 maybe_wait_bpf_programs(map); 208 209 return err; 210 } 211 212 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 213 __u64 flags) 214 { 215 void *ptr; 216 int err; 217 218 if (bpf_map_is_dev_bound(map)) 219 return bpf_map_offload_lookup_elem(map, key, value); 220 221 bpf_disable_instrumentation(); 222 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 223 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 224 err = bpf_percpu_hash_copy(map, key, value); 225 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 226 err = bpf_percpu_array_copy(map, key, value); 227 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 228 err = bpf_percpu_cgroup_storage_copy(map, key, value); 229 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 230 err = bpf_stackmap_copy(map, key, value); 231 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 232 err = bpf_fd_array_map_lookup_elem(map, key, value); 233 } else if (IS_FD_HASH(map)) { 234 err = bpf_fd_htab_map_lookup_elem(map, key, value); 235 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 236 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 237 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 238 map->map_type == BPF_MAP_TYPE_STACK) { 239 err = map->ops->map_peek_elem(map, value); 240 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 241 /* struct_ops map requires directly updating "value" */ 242 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 243 } else { 244 rcu_read_lock(); 245 if (map->ops->map_lookup_elem_sys_only) 246 ptr = map->ops->map_lookup_elem_sys_only(map, key); 247 else 248 ptr = map->ops->map_lookup_elem(map, key); 249 if (IS_ERR(ptr)) { 250 err = PTR_ERR(ptr); 251 } else if (!ptr) { 252 err = -ENOENT; 253 } else { 254 err = 0; 255 if (flags & BPF_F_LOCK) 256 /* lock 'ptr' and copy everything but lock */ 257 copy_map_value_locked(map, value, ptr, true); 258 else 259 copy_map_value(map, value, ptr); 260 /* mask lock, since value wasn't zero inited */ 261 check_and_init_map_lock(map, value); 262 } 263 rcu_read_unlock(); 264 } 265 266 bpf_enable_instrumentation(); 267 maybe_wait_bpf_programs(map); 268 269 return err; 270 } 271 272 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 273 { 274 /* We really just want to fail instead of triggering OOM killer 275 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 276 * which is used for lower order allocation requests. 277 * 278 * It has been observed that higher order allocation requests done by 279 * vmalloc with __GFP_NORETRY being set might fail due to not trying 280 * to reclaim memory from the page cache, thus we set 281 * __GFP_RETRY_MAYFAIL to avoid such situations. 282 */ 283 284 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; 285 void *area; 286 287 if (size >= SIZE_MAX) 288 return NULL; 289 290 /* kmalloc()'ed memory can't be mmap()'ed */ 291 if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 292 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, 293 numa_node); 294 if (area != NULL) 295 return area; 296 } 297 if (mmapable) { 298 BUG_ON(!PAGE_ALIGNED(size)); 299 return vmalloc_user_node_flags(size, numa_node, GFP_KERNEL | 300 __GFP_RETRY_MAYFAIL | flags); 301 } 302 return __vmalloc_node_flags_caller(size, numa_node, 303 GFP_KERNEL | __GFP_RETRY_MAYFAIL | 304 flags, __builtin_return_address(0)); 305 } 306 307 void *bpf_map_area_alloc(u64 size, int numa_node) 308 { 309 return __bpf_map_area_alloc(size, numa_node, false); 310 } 311 312 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 313 { 314 return __bpf_map_area_alloc(size, numa_node, true); 315 } 316 317 void bpf_map_area_free(void *area) 318 { 319 kvfree(area); 320 } 321 322 static u32 bpf_map_flags_retain_permanent(u32 flags) 323 { 324 /* Some map creation flags are not tied to the map object but 325 * rather to the map fd instead, so they have no meaning upon 326 * map object inspection since multiple file descriptors with 327 * different (access) properties can exist here. Thus, given 328 * this has zero meaning for the map itself, lets clear these 329 * from here. 330 */ 331 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 332 } 333 334 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 335 { 336 map->map_type = attr->map_type; 337 map->key_size = attr->key_size; 338 map->value_size = attr->value_size; 339 map->max_entries = attr->max_entries; 340 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 341 map->numa_node = bpf_map_attr_numa_node(attr); 342 } 343 344 static int bpf_charge_memlock(struct user_struct *user, u32 pages) 345 { 346 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 347 348 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) { 349 atomic_long_sub(pages, &user->locked_vm); 350 return -EPERM; 351 } 352 return 0; 353 } 354 355 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages) 356 { 357 if (user) 358 atomic_long_sub(pages, &user->locked_vm); 359 } 360 361 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size) 362 { 363 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT; 364 struct user_struct *user; 365 int ret; 366 367 if (size >= U32_MAX - PAGE_SIZE) 368 return -E2BIG; 369 370 user = get_current_user(); 371 ret = bpf_charge_memlock(user, pages); 372 if (ret) { 373 free_uid(user); 374 return ret; 375 } 376 377 mem->pages = pages; 378 mem->user = user; 379 380 return 0; 381 } 382 383 void bpf_map_charge_finish(struct bpf_map_memory *mem) 384 { 385 bpf_uncharge_memlock(mem->user, mem->pages); 386 free_uid(mem->user); 387 } 388 389 void bpf_map_charge_move(struct bpf_map_memory *dst, 390 struct bpf_map_memory *src) 391 { 392 *dst = *src; 393 394 /* Make sure src will not be used for the redundant uncharging. */ 395 memset(src, 0, sizeof(struct bpf_map_memory)); 396 } 397 398 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages) 399 { 400 int ret; 401 402 ret = bpf_charge_memlock(map->memory.user, pages); 403 if (ret) 404 return ret; 405 map->memory.pages += pages; 406 return ret; 407 } 408 409 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages) 410 { 411 bpf_uncharge_memlock(map->memory.user, pages); 412 map->memory.pages -= pages; 413 } 414 415 static int bpf_map_alloc_id(struct bpf_map *map) 416 { 417 int id; 418 419 idr_preload(GFP_KERNEL); 420 spin_lock_bh(&map_idr_lock); 421 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 422 if (id > 0) 423 map->id = id; 424 spin_unlock_bh(&map_idr_lock); 425 idr_preload_end(); 426 427 if (WARN_ON_ONCE(!id)) 428 return -ENOSPC; 429 430 return id > 0 ? 0 : id; 431 } 432 433 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 434 { 435 unsigned long flags; 436 437 /* Offloaded maps are removed from the IDR store when their device 438 * disappears - even if someone holds an fd to them they are unusable, 439 * the memory is gone, all ops will fail; they are simply waiting for 440 * refcnt to drop to be freed. 441 */ 442 if (!map->id) 443 return; 444 445 if (do_idr_lock) 446 spin_lock_irqsave(&map_idr_lock, flags); 447 else 448 __acquire(&map_idr_lock); 449 450 idr_remove(&map_idr, map->id); 451 map->id = 0; 452 453 if (do_idr_lock) 454 spin_unlock_irqrestore(&map_idr_lock, flags); 455 else 456 __release(&map_idr_lock); 457 } 458 459 /* called from workqueue */ 460 static void bpf_map_free_deferred(struct work_struct *work) 461 { 462 struct bpf_map *map = container_of(work, struct bpf_map, work); 463 struct bpf_map_memory mem; 464 465 bpf_map_charge_move(&mem, &map->memory); 466 security_bpf_map_free(map); 467 /* implementation dependent freeing */ 468 map->ops->map_free(map); 469 bpf_map_charge_finish(&mem); 470 } 471 472 static void bpf_map_put_uref(struct bpf_map *map) 473 { 474 if (atomic64_dec_and_test(&map->usercnt)) { 475 if (map->ops->map_release_uref) 476 map->ops->map_release_uref(map); 477 } 478 } 479 480 /* decrement map refcnt and schedule it for freeing via workqueue 481 * (unrelying map implementation ops->map_free() might sleep) 482 */ 483 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 484 { 485 if (atomic64_dec_and_test(&map->refcnt)) { 486 /* bpf_map_free_id() must be called first */ 487 bpf_map_free_id(map, do_idr_lock); 488 btf_put(map->btf); 489 INIT_WORK(&map->work, bpf_map_free_deferred); 490 schedule_work(&map->work); 491 } 492 } 493 494 void bpf_map_put(struct bpf_map *map) 495 { 496 __bpf_map_put(map, true); 497 } 498 EXPORT_SYMBOL_GPL(bpf_map_put); 499 500 void bpf_map_put_with_uref(struct bpf_map *map) 501 { 502 bpf_map_put_uref(map); 503 bpf_map_put(map); 504 } 505 506 static int bpf_map_release(struct inode *inode, struct file *filp) 507 { 508 struct bpf_map *map = filp->private_data; 509 510 if (map->ops->map_release) 511 map->ops->map_release(map, filp); 512 513 bpf_map_put_with_uref(map); 514 return 0; 515 } 516 517 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 518 { 519 fmode_t mode = f.file->f_mode; 520 521 /* Our file permissions may have been overridden by global 522 * map permissions facing syscall side. 523 */ 524 if (READ_ONCE(map->frozen)) 525 mode &= ~FMODE_CAN_WRITE; 526 return mode; 527 } 528 529 #ifdef CONFIG_PROC_FS 530 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 531 { 532 const struct bpf_map *map = filp->private_data; 533 const struct bpf_array *array; 534 u32 type = 0, jited = 0; 535 536 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 537 array = container_of(map, struct bpf_array, map); 538 type = array->aux->type; 539 jited = array->aux->jited; 540 } 541 542 seq_printf(m, 543 "map_type:\t%u\n" 544 "key_size:\t%u\n" 545 "value_size:\t%u\n" 546 "max_entries:\t%u\n" 547 "map_flags:\t%#x\n" 548 "memlock:\t%llu\n" 549 "map_id:\t%u\n" 550 "frozen:\t%u\n", 551 map->map_type, 552 map->key_size, 553 map->value_size, 554 map->max_entries, 555 map->map_flags, 556 map->memory.pages * 1ULL << PAGE_SHIFT, 557 map->id, 558 READ_ONCE(map->frozen)); 559 if (type) { 560 seq_printf(m, "owner_prog_type:\t%u\n", type); 561 seq_printf(m, "owner_jited:\t%u\n", jited); 562 } 563 } 564 #endif 565 566 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 567 loff_t *ppos) 568 { 569 /* We need this handler such that alloc_file() enables 570 * f_mode with FMODE_CAN_READ. 571 */ 572 return -EINVAL; 573 } 574 575 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 576 size_t siz, loff_t *ppos) 577 { 578 /* We need this handler such that alloc_file() enables 579 * f_mode with FMODE_CAN_WRITE. 580 */ 581 return -EINVAL; 582 } 583 584 /* called for any extra memory-mapped regions (except initial) */ 585 static void bpf_map_mmap_open(struct vm_area_struct *vma) 586 { 587 struct bpf_map *map = vma->vm_file->private_data; 588 589 if (vma->vm_flags & VM_MAYWRITE) { 590 mutex_lock(&map->freeze_mutex); 591 map->writecnt++; 592 mutex_unlock(&map->freeze_mutex); 593 } 594 } 595 596 /* called for all unmapped memory region (including initial) */ 597 static void bpf_map_mmap_close(struct vm_area_struct *vma) 598 { 599 struct bpf_map *map = vma->vm_file->private_data; 600 601 if (vma->vm_flags & VM_MAYWRITE) { 602 mutex_lock(&map->freeze_mutex); 603 map->writecnt--; 604 mutex_unlock(&map->freeze_mutex); 605 } 606 } 607 608 static const struct vm_operations_struct bpf_map_default_vmops = { 609 .open = bpf_map_mmap_open, 610 .close = bpf_map_mmap_close, 611 }; 612 613 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 614 { 615 struct bpf_map *map = filp->private_data; 616 int err; 617 618 if (!map->ops->map_mmap || map_value_has_spin_lock(map)) 619 return -ENOTSUPP; 620 621 if (!(vma->vm_flags & VM_SHARED)) 622 return -EINVAL; 623 624 mutex_lock(&map->freeze_mutex); 625 626 if (vma->vm_flags & VM_WRITE) { 627 if (map->frozen) { 628 err = -EPERM; 629 goto out; 630 } 631 /* map is meant to be read-only, so do not allow mapping as 632 * writable, because it's possible to leak a writable page 633 * reference and allows user-space to still modify it after 634 * freezing, while verifier will assume contents do not change 635 */ 636 if (map->map_flags & BPF_F_RDONLY_PROG) { 637 err = -EACCES; 638 goto out; 639 } 640 } 641 642 /* set default open/close callbacks */ 643 vma->vm_ops = &bpf_map_default_vmops; 644 vma->vm_private_data = map; 645 vma->vm_flags &= ~VM_MAYEXEC; 646 if (!(vma->vm_flags & VM_WRITE)) 647 /* disallow re-mapping with PROT_WRITE */ 648 vma->vm_flags &= ~VM_MAYWRITE; 649 650 err = map->ops->map_mmap(map, vma); 651 if (err) 652 goto out; 653 654 if (vma->vm_flags & VM_MAYWRITE) 655 map->writecnt++; 656 out: 657 mutex_unlock(&map->freeze_mutex); 658 return err; 659 } 660 661 const struct file_operations bpf_map_fops = { 662 #ifdef CONFIG_PROC_FS 663 .show_fdinfo = bpf_map_show_fdinfo, 664 #endif 665 .release = bpf_map_release, 666 .read = bpf_dummy_read, 667 .write = bpf_dummy_write, 668 .mmap = bpf_map_mmap, 669 }; 670 671 int bpf_map_new_fd(struct bpf_map *map, int flags) 672 { 673 int ret; 674 675 ret = security_bpf_map(map, OPEN_FMODE(flags)); 676 if (ret < 0) 677 return ret; 678 679 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 680 flags | O_CLOEXEC); 681 } 682 683 int bpf_get_file_flag(int flags) 684 { 685 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 686 return -EINVAL; 687 if (flags & BPF_F_RDONLY) 688 return O_RDONLY; 689 if (flags & BPF_F_WRONLY) 690 return O_WRONLY; 691 return O_RDWR; 692 } 693 694 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 695 #define CHECK_ATTR(CMD) \ 696 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 697 sizeof(attr->CMD##_LAST_FIELD), 0, \ 698 sizeof(*attr) - \ 699 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 700 sizeof(attr->CMD##_LAST_FIELD)) != NULL 701 702 /* dst and src must have at least "size" number of bytes. 703 * Return strlen on success and < 0 on error. 704 */ 705 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 706 { 707 const char *end = src + size; 708 const char *orig_src = src; 709 710 memset(dst, 0, size); 711 /* Copy all isalnum(), '_' and '.' chars. */ 712 while (src < end && *src) { 713 if (!isalnum(*src) && 714 *src != '_' && *src != '.') 715 return -EINVAL; 716 *dst++ = *src++; 717 } 718 719 /* No '\0' found in "size" number of bytes */ 720 if (src == end) 721 return -EINVAL; 722 723 return src - orig_src; 724 } 725 726 int map_check_no_btf(const struct bpf_map *map, 727 const struct btf *btf, 728 const struct btf_type *key_type, 729 const struct btf_type *value_type) 730 { 731 return -ENOTSUPP; 732 } 733 734 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 735 u32 btf_key_id, u32 btf_value_id) 736 { 737 const struct btf_type *key_type, *value_type; 738 u32 key_size, value_size; 739 int ret = 0; 740 741 /* Some maps allow key to be unspecified. */ 742 if (btf_key_id) { 743 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 744 if (!key_type || key_size != map->key_size) 745 return -EINVAL; 746 } else { 747 key_type = btf_type_by_id(btf, 0); 748 if (!map->ops->map_check_btf) 749 return -EINVAL; 750 } 751 752 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 753 if (!value_type || value_size != map->value_size) 754 return -EINVAL; 755 756 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 757 758 if (map_value_has_spin_lock(map)) { 759 if (map->map_flags & BPF_F_RDONLY_PROG) 760 return -EACCES; 761 if (map->map_type != BPF_MAP_TYPE_HASH && 762 map->map_type != BPF_MAP_TYPE_ARRAY && 763 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 764 map->map_type != BPF_MAP_TYPE_SK_STORAGE) 765 return -ENOTSUPP; 766 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 767 map->value_size) { 768 WARN_ONCE(1, 769 "verifier bug spin_lock_off %d value_size %d\n", 770 map->spin_lock_off, map->value_size); 771 return -EFAULT; 772 } 773 } 774 775 if (map->ops->map_check_btf) 776 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 777 778 return ret; 779 } 780 781 #define BPF_MAP_CREATE_LAST_FIELD btf_vmlinux_value_type_id 782 /* called via syscall */ 783 static int map_create(union bpf_attr *attr) 784 { 785 int numa_node = bpf_map_attr_numa_node(attr); 786 struct bpf_map_memory mem; 787 struct bpf_map *map; 788 int f_flags; 789 int err; 790 791 err = CHECK_ATTR(BPF_MAP_CREATE); 792 if (err) 793 return -EINVAL; 794 795 if (attr->btf_vmlinux_value_type_id) { 796 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 797 attr->btf_key_type_id || attr->btf_value_type_id) 798 return -EINVAL; 799 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 800 return -EINVAL; 801 } 802 803 f_flags = bpf_get_file_flag(attr->map_flags); 804 if (f_flags < 0) 805 return f_flags; 806 807 if (numa_node != NUMA_NO_NODE && 808 ((unsigned int)numa_node >= nr_node_ids || 809 !node_online(numa_node))) 810 return -EINVAL; 811 812 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 813 map = find_and_alloc_map(attr); 814 if (IS_ERR(map)) 815 return PTR_ERR(map); 816 817 err = bpf_obj_name_cpy(map->name, attr->map_name, 818 sizeof(attr->map_name)); 819 if (err < 0) 820 goto free_map; 821 822 atomic64_set(&map->refcnt, 1); 823 atomic64_set(&map->usercnt, 1); 824 mutex_init(&map->freeze_mutex); 825 826 map->spin_lock_off = -EINVAL; 827 if (attr->btf_key_type_id || attr->btf_value_type_id || 828 /* Even the map's value is a kernel's struct, 829 * the bpf_prog.o must have BTF to begin with 830 * to figure out the corresponding kernel's 831 * counter part. Thus, attr->btf_fd has 832 * to be valid also. 833 */ 834 attr->btf_vmlinux_value_type_id) { 835 struct btf *btf; 836 837 btf = btf_get_by_fd(attr->btf_fd); 838 if (IS_ERR(btf)) { 839 err = PTR_ERR(btf); 840 goto free_map; 841 } 842 map->btf = btf; 843 844 if (attr->btf_value_type_id) { 845 err = map_check_btf(map, btf, attr->btf_key_type_id, 846 attr->btf_value_type_id); 847 if (err) 848 goto free_map; 849 } 850 851 map->btf_key_type_id = attr->btf_key_type_id; 852 map->btf_value_type_id = attr->btf_value_type_id; 853 map->btf_vmlinux_value_type_id = 854 attr->btf_vmlinux_value_type_id; 855 } 856 857 err = security_bpf_map_alloc(map); 858 if (err) 859 goto free_map; 860 861 err = bpf_map_alloc_id(map); 862 if (err) 863 goto free_map_sec; 864 865 err = bpf_map_new_fd(map, f_flags); 866 if (err < 0) { 867 /* failed to allocate fd. 868 * bpf_map_put_with_uref() is needed because the above 869 * bpf_map_alloc_id() has published the map 870 * to the userspace and the userspace may 871 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 872 */ 873 bpf_map_put_with_uref(map); 874 return err; 875 } 876 877 return err; 878 879 free_map_sec: 880 security_bpf_map_free(map); 881 free_map: 882 btf_put(map->btf); 883 bpf_map_charge_move(&mem, &map->memory); 884 map->ops->map_free(map); 885 bpf_map_charge_finish(&mem); 886 return err; 887 } 888 889 /* if error is returned, fd is released. 890 * On success caller should complete fd access with matching fdput() 891 */ 892 struct bpf_map *__bpf_map_get(struct fd f) 893 { 894 if (!f.file) 895 return ERR_PTR(-EBADF); 896 if (f.file->f_op != &bpf_map_fops) { 897 fdput(f); 898 return ERR_PTR(-EINVAL); 899 } 900 901 return f.file->private_data; 902 } 903 904 void bpf_map_inc(struct bpf_map *map) 905 { 906 atomic64_inc(&map->refcnt); 907 } 908 EXPORT_SYMBOL_GPL(bpf_map_inc); 909 910 void bpf_map_inc_with_uref(struct bpf_map *map) 911 { 912 atomic64_inc(&map->refcnt); 913 atomic64_inc(&map->usercnt); 914 } 915 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 916 917 struct bpf_map *bpf_map_get(u32 ufd) 918 { 919 struct fd f = fdget(ufd); 920 struct bpf_map *map; 921 922 map = __bpf_map_get(f); 923 if (IS_ERR(map)) 924 return map; 925 926 bpf_map_inc(map); 927 fdput(f); 928 929 return map; 930 } 931 932 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 933 { 934 struct fd f = fdget(ufd); 935 struct bpf_map *map; 936 937 map = __bpf_map_get(f); 938 if (IS_ERR(map)) 939 return map; 940 941 bpf_map_inc_with_uref(map); 942 fdput(f); 943 944 return map; 945 } 946 947 /* map_idr_lock should have been held */ 948 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 949 { 950 int refold; 951 952 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 953 if (!refold) 954 return ERR_PTR(-ENOENT); 955 if (uref) 956 atomic64_inc(&map->usercnt); 957 958 return map; 959 } 960 961 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 962 { 963 spin_lock_bh(&map_idr_lock); 964 map = __bpf_map_inc_not_zero(map, false); 965 spin_unlock_bh(&map_idr_lock); 966 967 return map; 968 } 969 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 970 971 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 972 { 973 return -ENOTSUPP; 974 } 975 976 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 977 { 978 if (key_size) 979 return memdup_user(ukey, key_size); 980 981 if (ukey) 982 return ERR_PTR(-EINVAL); 983 984 return NULL; 985 } 986 987 /* last field in 'union bpf_attr' used by this command */ 988 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 989 990 static int map_lookup_elem(union bpf_attr *attr) 991 { 992 void __user *ukey = u64_to_user_ptr(attr->key); 993 void __user *uvalue = u64_to_user_ptr(attr->value); 994 int ufd = attr->map_fd; 995 struct bpf_map *map; 996 void *key, *value; 997 u32 value_size; 998 struct fd f; 999 int err; 1000 1001 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1002 return -EINVAL; 1003 1004 if (attr->flags & ~BPF_F_LOCK) 1005 return -EINVAL; 1006 1007 f = fdget(ufd); 1008 map = __bpf_map_get(f); 1009 if (IS_ERR(map)) 1010 return PTR_ERR(map); 1011 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1012 err = -EPERM; 1013 goto err_put; 1014 } 1015 1016 if ((attr->flags & BPF_F_LOCK) && 1017 !map_value_has_spin_lock(map)) { 1018 err = -EINVAL; 1019 goto err_put; 1020 } 1021 1022 key = __bpf_copy_key(ukey, map->key_size); 1023 if (IS_ERR(key)) { 1024 err = PTR_ERR(key); 1025 goto err_put; 1026 } 1027 1028 value_size = bpf_map_value_size(map); 1029 1030 err = -ENOMEM; 1031 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1032 if (!value) 1033 goto free_key; 1034 1035 err = bpf_map_copy_value(map, key, value, attr->flags); 1036 if (err) 1037 goto free_value; 1038 1039 err = -EFAULT; 1040 if (copy_to_user(uvalue, value, value_size) != 0) 1041 goto free_value; 1042 1043 err = 0; 1044 1045 free_value: 1046 kfree(value); 1047 free_key: 1048 kfree(key); 1049 err_put: 1050 fdput(f); 1051 return err; 1052 } 1053 1054 1055 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1056 1057 static int map_update_elem(union bpf_attr *attr) 1058 { 1059 void __user *ukey = u64_to_user_ptr(attr->key); 1060 void __user *uvalue = u64_to_user_ptr(attr->value); 1061 int ufd = attr->map_fd; 1062 struct bpf_map *map; 1063 void *key, *value; 1064 u32 value_size; 1065 struct fd f; 1066 int err; 1067 1068 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1069 return -EINVAL; 1070 1071 f = fdget(ufd); 1072 map = __bpf_map_get(f); 1073 if (IS_ERR(map)) 1074 return PTR_ERR(map); 1075 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1076 err = -EPERM; 1077 goto err_put; 1078 } 1079 1080 if ((attr->flags & BPF_F_LOCK) && 1081 !map_value_has_spin_lock(map)) { 1082 err = -EINVAL; 1083 goto err_put; 1084 } 1085 1086 key = __bpf_copy_key(ukey, map->key_size); 1087 if (IS_ERR(key)) { 1088 err = PTR_ERR(key); 1089 goto err_put; 1090 } 1091 1092 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1093 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 1094 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 1095 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 1096 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 1097 else 1098 value_size = map->value_size; 1099 1100 err = -ENOMEM; 1101 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1102 if (!value) 1103 goto free_key; 1104 1105 err = -EFAULT; 1106 if (copy_from_user(value, uvalue, value_size) != 0) 1107 goto free_value; 1108 1109 err = bpf_map_update_value(map, f, key, value, attr->flags); 1110 1111 free_value: 1112 kfree(value); 1113 free_key: 1114 kfree(key); 1115 err_put: 1116 fdput(f); 1117 return err; 1118 } 1119 1120 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1121 1122 static int map_delete_elem(union bpf_attr *attr) 1123 { 1124 void __user *ukey = u64_to_user_ptr(attr->key); 1125 int ufd = attr->map_fd; 1126 struct bpf_map *map; 1127 struct fd f; 1128 void *key; 1129 int err; 1130 1131 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1132 return -EINVAL; 1133 1134 f = fdget(ufd); 1135 map = __bpf_map_get(f); 1136 if (IS_ERR(map)) 1137 return PTR_ERR(map); 1138 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1139 err = -EPERM; 1140 goto err_put; 1141 } 1142 1143 key = __bpf_copy_key(ukey, map->key_size); 1144 if (IS_ERR(key)) { 1145 err = PTR_ERR(key); 1146 goto err_put; 1147 } 1148 1149 if (bpf_map_is_dev_bound(map)) { 1150 err = bpf_map_offload_delete_elem(map, key); 1151 goto out; 1152 } else if (IS_FD_PROG_ARRAY(map) || 1153 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1154 /* These maps require sleepable context */ 1155 err = map->ops->map_delete_elem(map, key); 1156 goto out; 1157 } 1158 1159 bpf_disable_instrumentation(); 1160 rcu_read_lock(); 1161 err = map->ops->map_delete_elem(map, key); 1162 rcu_read_unlock(); 1163 bpf_enable_instrumentation(); 1164 maybe_wait_bpf_programs(map); 1165 out: 1166 kfree(key); 1167 err_put: 1168 fdput(f); 1169 return err; 1170 } 1171 1172 /* last field in 'union bpf_attr' used by this command */ 1173 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1174 1175 static int map_get_next_key(union bpf_attr *attr) 1176 { 1177 void __user *ukey = u64_to_user_ptr(attr->key); 1178 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1179 int ufd = attr->map_fd; 1180 struct bpf_map *map; 1181 void *key, *next_key; 1182 struct fd f; 1183 int err; 1184 1185 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1186 return -EINVAL; 1187 1188 f = fdget(ufd); 1189 map = __bpf_map_get(f); 1190 if (IS_ERR(map)) 1191 return PTR_ERR(map); 1192 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1193 err = -EPERM; 1194 goto err_put; 1195 } 1196 1197 if (ukey) { 1198 key = __bpf_copy_key(ukey, map->key_size); 1199 if (IS_ERR(key)) { 1200 err = PTR_ERR(key); 1201 goto err_put; 1202 } 1203 } else { 1204 key = NULL; 1205 } 1206 1207 err = -ENOMEM; 1208 next_key = kmalloc(map->key_size, GFP_USER); 1209 if (!next_key) 1210 goto free_key; 1211 1212 if (bpf_map_is_dev_bound(map)) { 1213 err = bpf_map_offload_get_next_key(map, key, next_key); 1214 goto out; 1215 } 1216 1217 rcu_read_lock(); 1218 err = map->ops->map_get_next_key(map, key, next_key); 1219 rcu_read_unlock(); 1220 out: 1221 if (err) 1222 goto free_next_key; 1223 1224 err = -EFAULT; 1225 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1226 goto free_next_key; 1227 1228 err = 0; 1229 1230 free_next_key: 1231 kfree(next_key); 1232 free_key: 1233 kfree(key); 1234 err_put: 1235 fdput(f); 1236 return err; 1237 } 1238 1239 int generic_map_delete_batch(struct bpf_map *map, 1240 const union bpf_attr *attr, 1241 union bpf_attr __user *uattr) 1242 { 1243 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1244 u32 cp, max_count; 1245 int err = 0; 1246 void *key; 1247 1248 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1249 return -EINVAL; 1250 1251 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1252 !map_value_has_spin_lock(map)) { 1253 return -EINVAL; 1254 } 1255 1256 max_count = attr->batch.count; 1257 if (!max_count) 1258 return 0; 1259 1260 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1261 if (!key) 1262 return -ENOMEM; 1263 1264 for (cp = 0; cp < max_count; cp++) { 1265 err = -EFAULT; 1266 if (copy_from_user(key, keys + cp * map->key_size, 1267 map->key_size)) 1268 break; 1269 1270 if (bpf_map_is_dev_bound(map)) { 1271 err = bpf_map_offload_delete_elem(map, key); 1272 break; 1273 } 1274 1275 bpf_disable_instrumentation(); 1276 rcu_read_lock(); 1277 err = map->ops->map_delete_elem(map, key); 1278 rcu_read_unlock(); 1279 bpf_enable_instrumentation(); 1280 maybe_wait_bpf_programs(map); 1281 if (err) 1282 break; 1283 } 1284 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1285 err = -EFAULT; 1286 1287 kfree(key); 1288 return err; 1289 } 1290 1291 int generic_map_update_batch(struct bpf_map *map, 1292 const union bpf_attr *attr, 1293 union bpf_attr __user *uattr) 1294 { 1295 void __user *values = u64_to_user_ptr(attr->batch.values); 1296 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1297 u32 value_size, cp, max_count; 1298 int ufd = attr->map_fd; 1299 void *key, *value; 1300 struct fd f; 1301 int err = 0; 1302 1303 f = fdget(ufd); 1304 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1305 return -EINVAL; 1306 1307 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1308 !map_value_has_spin_lock(map)) { 1309 return -EINVAL; 1310 } 1311 1312 value_size = bpf_map_value_size(map); 1313 1314 max_count = attr->batch.count; 1315 if (!max_count) 1316 return 0; 1317 1318 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1319 if (!key) 1320 return -ENOMEM; 1321 1322 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1323 if (!value) { 1324 kfree(key); 1325 return -ENOMEM; 1326 } 1327 1328 for (cp = 0; cp < max_count; cp++) { 1329 err = -EFAULT; 1330 if (copy_from_user(key, keys + cp * map->key_size, 1331 map->key_size) || 1332 copy_from_user(value, values + cp * value_size, value_size)) 1333 break; 1334 1335 err = bpf_map_update_value(map, f, key, value, 1336 attr->batch.elem_flags); 1337 1338 if (err) 1339 break; 1340 } 1341 1342 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1343 err = -EFAULT; 1344 1345 kfree(value); 1346 kfree(key); 1347 return err; 1348 } 1349 1350 #define MAP_LOOKUP_RETRIES 3 1351 1352 int generic_map_lookup_batch(struct bpf_map *map, 1353 const union bpf_attr *attr, 1354 union bpf_attr __user *uattr) 1355 { 1356 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1357 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1358 void __user *values = u64_to_user_ptr(attr->batch.values); 1359 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1360 void *buf, *buf_prevkey, *prev_key, *key, *value; 1361 int err, retry = MAP_LOOKUP_RETRIES; 1362 u32 value_size, cp, max_count; 1363 1364 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1365 return -EINVAL; 1366 1367 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1368 !map_value_has_spin_lock(map)) 1369 return -EINVAL; 1370 1371 value_size = bpf_map_value_size(map); 1372 1373 max_count = attr->batch.count; 1374 if (!max_count) 1375 return 0; 1376 1377 if (put_user(0, &uattr->batch.count)) 1378 return -EFAULT; 1379 1380 buf_prevkey = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1381 if (!buf_prevkey) 1382 return -ENOMEM; 1383 1384 buf = kmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1385 if (!buf) { 1386 kvfree(buf_prevkey); 1387 return -ENOMEM; 1388 } 1389 1390 err = -EFAULT; 1391 prev_key = NULL; 1392 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1393 goto free_buf; 1394 key = buf; 1395 value = key + map->key_size; 1396 if (ubatch) 1397 prev_key = buf_prevkey; 1398 1399 for (cp = 0; cp < max_count;) { 1400 rcu_read_lock(); 1401 err = map->ops->map_get_next_key(map, prev_key, key); 1402 rcu_read_unlock(); 1403 if (err) 1404 break; 1405 err = bpf_map_copy_value(map, key, value, 1406 attr->batch.elem_flags); 1407 1408 if (err == -ENOENT) { 1409 if (retry) { 1410 retry--; 1411 continue; 1412 } 1413 err = -EINTR; 1414 break; 1415 } 1416 1417 if (err) 1418 goto free_buf; 1419 1420 if (copy_to_user(keys + cp * map->key_size, key, 1421 map->key_size)) { 1422 err = -EFAULT; 1423 goto free_buf; 1424 } 1425 if (copy_to_user(values + cp * value_size, value, value_size)) { 1426 err = -EFAULT; 1427 goto free_buf; 1428 } 1429 1430 if (!prev_key) 1431 prev_key = buf_prevkey; 1432 1433 swap(prev_key, key); 1434 retry = MAP_LOOKUP_RETRIES; 1435 cp++; 1436 } 1437 1438 if (err == -EFAULT) 1439 goto free_buf; 1440 1441 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1442 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1443 err = -EFAULT; 1444 1445 free_buf: 1446 kfree(buf_prevkey); 1447 kfree(buf); 1448 return err; 1449 } 1450 1451 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value 1452 1453 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1454 { 1455 void __user *ukey = u64_to_user_ptr(attr->key); 1456 void __user *uvalue = u64_to_user_ptr(attr->value); 1457 int ufd = attr->map_fd; 1458 struct bpf_map *map; 1459 void *key, *value; 1460 u32 value_size; 1461 struct fd f; 1462 int err; 1463 1464 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1465 return -EINVAL; 1466 1467 f = fdget(ufd); 1468 map = __bpf_map_get(f); 1469 if (IS_ERR(map)) 1470 return PTR_ERR(map); 1471 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1472 err = -EPERM; 1473 goto err_put; 1474 } 1475 1476 key = __bpf_copy_key(ukey, map->key_size); 1477 if (IS_ERR(key)) { 1478 err = PTR_ERR(key); 1479 goto err_put; 1480 } 1481 1482 value_size = map->value_size; 1483 1484 err = -ENOMEM; 1485 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1486 if (!value) 1487 goto free_key; 1488 1489 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1490 map->map_type == BPF_MAP_TYPE_STACK) { 1491 err = map->ops->map_pop_elem(map, value); 1492 } else { 1493 err = -ENOTSUPP; 1494 } 1495 1496 if (err) 1497 goto free_value; 1498 1499 if (copy_to_user(uvalue, value, value_size) != 0) { 1500 err = -EFAULT; 1501 goto free_value; 1502 } 1503 1504 err = 0; 1505 1506 free_value: 1507 kfree(value); 1508 free_key: 1509 kfree(key); 1510 err_put: 1511 fdput(f); 1512 return err; 1513 } 1514 1515 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1516 1517 static int map_freeze(const union bpf_attr *attr) 1518 { 1519 int err = 0, ufd = attr->map_fd; 1520 struct bpf_map *map; 1521 struct fd f; 1522 1523 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1524 return -EINVAL; 1525 1526 f = fdget(ufd); 1527 map = __bpf_map_get(f); 1528 if (IS_ERR(map)) 1529 return PTR_ERR(map); 1530 1531 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1532 fdput(f); 1533 return -ENOTSUPP; 1534 } 1535 1536 mutex_lock(&map->freeze_mutex); 1537 1538 if (map->writecnt) { 1539 err = -EBUSY; 1540 goto err_put; 1541 } 1542 if (READ_ONCE(map->frozen)) { 1543 err = -EBUSY; 1544 goto err_put; 1545 } 1546 if (!capable(CAP_SYS_ADMIN)) { 1547 err = -EPERM; 1548 goto err_put; 1549 } 1550 1551 WRITE_ONCE(map->frozen, true); 1552 err_put: 1553 mutex_unlock(&map->freeze_mutex); 1554 fdput(f); 1555 return err; 1556 } 1557 1558 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1559 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1560 [_id] = & _name ## _prog_ops, 1561 #define BPF_MAP_TYPE(_id, _ops) 1562 #include <linux/bpf_types.h> 1563 #undef BPF_PROG_TYPE 1564 #undef BPF_MAP_TYPE 1565 }; 1566 1567 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1568 { 1569 const struct bpf_prog_ops *ops; 1570 1571 if (type >= ARRAY_SIZE(bpf_prog_types)) 1572 return -EINVAL; 1573 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1574 ops = bpf_prog_types[type]; 1575 if (!ops) 1576 return -EINVAL; 1577 1578 if (!bpf_prog_is_dev_bound(prog->aux)) 1579 prog->aux->ops = ops; 1580 else 1581 prog->aux->ops = &bpf_offload_prog_ops; 1582 prog->type = type; 1583 return 0; 1584 } 1585 1586 enum bpf_audit { 1587 BPF_AUDIT_LOAD, 1588 BPF_AUDIT_UNLOAD, 1589 BPF_AUDIT_MAX, 1590 }; 1591 1592 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1593 [BPF_AUDIT_LOAD] = "LOAD", 1594 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1595 }; 1596 1597 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1598 { 1599 struct audit_context *ctx = NULL; 1600 struct audit_buffer *ab; 1601 1602 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1603 return; 1604 if (audit_enabled == AUDIT_OFF) 1605 return; 1606 if (op == BPF_AUDIT_LOAD) 1607 ctx = audit_context(); 1608 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1609 if (unlikely(!ab)) 1610 return; 1611 audit_log_format(ab, "prog-id=%u op=%s", 1612 prog->aux->id, bpf_audit_str[op]); 1613 audit_log_end(ab); 1614 } 1615 1616 int __bpf_prog_charge(struct user_struct *user, u32 pages) 1617 { 1618 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 1619 unsigned long user_bufs; 1620 1621 if (user) { 1622 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 1623 if (user_bufs > memlock_limit) { 1624 atomic_long_sub(pages, &user->locked_vm); 1625 return -EPERM; 1626 } 1627 } 1628 1629 return 0; 1630 } 1631 1632 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 1633 { 1634 if (user) 1635 atomic_long_sub(pages, &user->locked_vm); 1636 } 1637 1638 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 1639 { 1640 struct user_struct *user = get_current_user(); 1641 int ret; 1642 1643 ret = __bpf_prog_charge(user, prog->pages); 1644 if (ret) { 1645 free_uid(user); 1646 return ret; 1647 } 1648 1649 prog->aux->user = user; 1650 return 0; 1651 } 1652 1653 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 1654 { 1655 struct user_struct *user = prog->aux->user; 1656 1657 __bpf_prog_uncharge(user, prog->pages); 1658 free_uid(user); 1659 } 1660 1661 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1662 { 1663 int id; 1664 1665 idr_preload(GFP_KERNEL); 1666 spin_lock_bh(&prog_idr_lock); 1667 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1668 if (id > 0) 1669 prog->aux->id = id; 1670 spin_unlock_bh(&prog_idr_lock); 1671 idr_preload_end(); 1672 1673 /* id is in [1, INT_MAX) */ 1674 if (WARN_ON_ONCE(!id)) 1675 return -ENOSPC; 1676 1677 return id > 0 ? 0 : id; 1678 } 1679 1680 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1681 { 1682 /* cBPF to eBPF migrations are currently not in the idr store. 1683 * Offloaded programs are removed from the store when their device 1684 * disappears - even if someone grabs an fd to them they are unusable, 1685 * simply waiting for refcnt to drop to be freed. 1686 */ 1687 if (!prog->aux->id) 1688 return; 1689 1690 if (do_idr_lock) 1691 spin_lock_bh(&prog_idr_lock); 1692 else 1693 __acquire(&prog_idr_lock); 1694 1695 idr_remove(&prog_idr, prog->aux->id); 1696 prog->aux->id = 0; 1697 1698 if (do_idr_lock) 1699 spin_unlock_bh(&prog_idr_lock); 1700 else 1701 __release(&prog_idr_lock); 1702 } 1703 1704 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1705 { 1706 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1707 1708 kvfree(aux->func_info); 1709 kfree(aux->func_info_aux); 1710 bpf_prog_uncharge_memlock(aux->prog); 1711 security_bpf_prog_free(aux); 1712 bpf_prog_free(aux->prog); 1713 } 1714 1715 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1716 { 1717 bpf_prog_kallsyms_del_all(prog); 1718 btf_put(prog->aux->btf); 1719 bpf_prog_free_linfo(prog); 1720 1721 if (deferred) 1722 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1723 else 1724 __bpf_prog_put_rcu(&prog->aux->rcu); 1725 } 1726 1727 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1728 { 1729 if (atomic64_dec_and_test(&prog->aux->refcnt)) { 1730 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1731 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1732 /* bpf_prog_free_id() must be called first */ 1733 bpf_prog_free_id(prog, do_idr_lock); 1734 __bpf_prog_put_noref(prog, true); 1735 } 1736 } 1737 1738 void bpf_prog_put(struct bpf_prog *prog) 1739 { 1740 __bpf_prog_put(prog, true); 1741 } 1742 EXPORT_SYMBOL_GPL(bpf_prog_put); 1743 1744 static int bpf_prog_release(struct inode *inode, struct file *filp) 1745 { 1746 struct bpf_prog *prog = filp->private_data; 1747 1748 bpf_prog_put(prog); 1749 return 0; 1750 } 1751 1752 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1753 struct bpf_prog_stats *stats) 1754 { 1755 u64 nsecs = 0, cnt = 0; 1756 int cpu; 1757 1758 for_each_possible_cpu(cpu) { 1759 const struct bpf_prog_stats *st; 1760 unsigned int start; 1761 u64 tnsecs, tcnt; 1762 1763 st = per_cpu_ptr(prog->aux->stats, cpu); 1764 do { 1765 start = u64_stats_fetch_begin_irq(&st->syncp); 1766 tnsecs = st->nsecs; 1767 tcnt = st->cnt; 1768 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1769 nsecs += tnsecs; 1770 cnt += tcnt; 1771 } 1772 stats->nsecs = nsecs; 1773 stats->cnt = cnt; 1774 } 1775 1776 #ifdef CONFIG_PROC_FS 1777 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1778 { 1779 const struct bpf_prog *prog = filp->private_data; 1780 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1781 struct bpf_prog_stats stats; 1782 1783 bpf_prog_get_stats(prog, &stats); 1784 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1785 seq_printf(m, 1786 "prog_type:\t%u\n" 1787 "prog_jited:\t%u\n" 1788 "prog_tag:\t%s\n" 1789 "memlock:\t%llu\n" 1790 "prog_id:\t%u\n" 1791 "run_time_ns:\t%llu\n" 1792 "run_cnt:\t%llu\n", 1793 prog->type, 1794 prog->jited, 1795 prog_tag, 1796 prog->pages * 1ULL << PAGE_SHIFT, 1797 prog->aux->id, 1798 stats.nsecs, 1799 stats.cnt); 1800 } 1801 #endif 1802 1803 const struct file_operations bpf_prog_fops = { 1804 #ifdef CONFIG_PROC_FS 1805 .show_fdinfo = bpf_prog_show_fdinfo, 1806 #endif 1807 .release = bpf_prog_release, 1808 .read = bpf_dummy_read, 1809 .write = bpf_dummy_write, 1810 }; 1811 1812 int bpf_prog_new_fd(struct bpf_prog *prog) 1813 { 1814 int ret; 1815 1816 ret = security_bpf_prog(prog); 1817 if (ret < 0) 1818 return ret; 1819 1820 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1821 O_RDWR | O_CLOEXEC); 1822 } 1823 1824 static struct bpf_prog *____bpf_prog_get(struct fd f) 1825 { 1826 if (!f.file) 1827 return ERR_PTR(-EBADF); 1828 if (f.file->f_op != &bpf_prog_fops) { 1829 fdput(f); 1830 return ERR_PTR(-EINVAL); 1831 } 1832 1833 return f.file->private_data; 1834 } 1835 1836 void bpf_prog_add(struct bpf_prog *prog, int i) 1837 { 1838 atomic64_add(i, &prog->aux->refcnt); 1839 } 1840 EXPORT_SYMBOL_GPL(bpf_prog_add); 1841 1842 void bpf_prog_sub(struct bpf_prog *prog, int i) 1843 { 1844 /* Only to be used for undoing previous bpf_prog_add() in some 1845 * error path. We still know that another entity in our call 1846 * path holds a reference to the program, thus atomic_sub() can 1847 * be safely used in such cases! 1848 */ 1849 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1850 } 1851 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1852 1853 void bpf_prog_inc(struct bpf_prog *prog) 1854 { 1855 atomic64_inc(&prog->aux->refcnt); 1856 } 1857 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1858 1859 /* prog_idr_lock should have been held */ 1860 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1861 { 1862 int refold; 1863 1864 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1865 1866 if (!refold) 1867 return ERR_PTR(-ENOENT); 1868 1869 return prog; 1870 } 1871 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1872 1873 bool bpf_prog_get_ok(struct bpf_prog *prog, 1874 enum bpf_prog_type *attach_type, bool attach_drv) 1875 { 1876 /* not an attachment, just a refcount inc, always allow */ 1877 if (!attach_type) 1878 return true; 1879 1880 if (prog->type != *attach_type) 1881 return false; 1882 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1883 return false; 1884 1885 return true; 1886 } 1887 1888 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1889 bool attach_drv) 1890 { 1891 struct fd f = fdget(ufd); 1892 struct bpf_prog *prog; 1893 1894 prog = ____bpf_prog_get(f); 1895 if (IS_ERR(prog)) 1896 return prog; 1897 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1898 prog = ERR_PTR(-EINVAL); 1899 goto out; 1900 } 1901 1902 bpf_prog_inc(prog); 1903 out: 1904 fdput(f); 1905 return prog; 1906 } 1907 1908 struct bpf_prog *bpf_prog_get(u32 ufd) 1909 { 1910 return __bpf_prog_get(ufd, NULL, false); 1911 } 1912 1913 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1914 bool attach_drv) 1915 { 1916 return __bpf_prog_get(ufd, &type, attach_drv); 1917 } 1918 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1919 1920 /* Initially all BPF programs could be loaded w/o specifying 1921 * expected_attach_type. Later for some of them specifying expected_attach_type 1922 * at load time became required so that program could be validated properly. 1923 * Programs of types that are allowed to be loaded both w/ and w/o (for 1924 * backward compatibility) expected_attach_type, should have the default attach 1925 * type assigned to expected_attach_type for the latter case, so that it can be 1926 * validated later at attach time. 1927 * 1928 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1929 * prog type requires it but has some attach types that have to be backward 1930 * compatible. 1931 */ 1932 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1933 { 1934 switch (attr->prog_type) { 1935 case BPF_PROG_TYPE_CGROUP_SOCK: 1936 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1937 * exist so checking for non-zero is the way to go here. 1938 */ 1939 if (!attr->expected_attach_type) 1940 attr->expected_attach_type = 1941 BPF_CGROUP_INET_SOCK_CREATE; 1942 break; 1943 } 1944 } 1945 1946 static int 1947 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 1948 enum bpf_attach_type expected_attach_type, 1949 u32 btf_id, u32 prog_fd) 1950 { 1951 if (btf_id) { 1952 if (btf_id > BTF_MAX_TYPE) 1953 return -EINVAL; 1954 1955 switch (prog_type) { 1956 case BPF_PROG_TYPE_TRACING: 1957 case BPF_PROG_TYPE_LSM: 1958 case BPF_PROG_TYPE_STRUCT_OPS: 1959 case BPF_PROG_TYPE_EXT: 1960 break; 1961 default: 1962 return -EINVAL; 1963 } 1964 } 1965 1966 if (prog_fd && prog_type != BPF_PROG_TYPE_TRACING && 1967 prog_type != BPF_PROG_TYPE_EXT) 1968 return -EINVAL; 1969 1970 switch (prog_type) { 1971 case BPF_PROG_TYPE_CGROUP_SOCK: 1972 switch (expected_attach_type) { 1973 case BPF_CGROUP_INET_SOCK_CREATE: 1974 case BPF_CGROUP_INET4_POST_BIND: 1975 case BPF_CGROUP_INET6_POST_BIND: 1976 return 0; 1977 default: 1978 return -EINVAL; 1979 } 1980 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1981 switch (expected_attach_type) { 1982 case BPF_CGROUP_INET4_BIND: 1983 case BPF_CGROUP_INET6_BIND: 1984 case BPF_CGROUP_INET4_CONNECT: 1985 case BPF_CGROUP_INET6_CONNECT: 1986 case BPF_CGROUP_UDP4_SENDMSG: 1987 case BPF_CGROUP_UDP6_SENDMSG: 1988 case BPF_CGROUP_UDP4_RECVMSG: 1989 case BPF_CGROUP_UDP6_RECVMSG: 1990 return 0; 1991 default: 1992 return -EINVAL; 1993 } 1994 case BPF_PROG_TYPE_CGROUP_SKB: 1995 switch (expected_attach_type) { 1996 case BPF_CGROUP_INET_INGRESS: 1997 case BPF_CGROUP_INET_EGRESS: 1998 return 0; 1999 default: 2000 return -EINVAL; 2001 } 2002 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2003 switch (expected_attach_type) { 2004 case BPF_CGROUP_SETSOCKOPT: 2005 case BPF_CGROUP_GETSOCKOPT: 2006 return 0; 2007 default: 2008 return -EINVAL; 2009 } 2010 case BPF_PROG_TYPE_EXT: 2011 if (expected_attach_type) 2012 return -EINVAL; 2013 /* fallthrough */ 2014 default: 2015 return 0; 2016 } 2017 } 2018 2019 /* last field in 'union bpf_attr' used by this command */ 2020 #define BPF_PROG_LOAD_LAST_FIELD attach_prog_fd 2021 2022 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 2023 { 2024 enum bpf_prog_type type = attr->prog_type; 2025 struct bpf_prog *prog; 2026 int err; 2027 char license[128]; 2028 bool is_gpl; 2029 2030 if (CHECK_ATTR(BPF_PROG_LOAD)) 2031 return -EINVAL; 2032 2033 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2034 BPF_F_ANY_ALIGNMENT | 2035 BPF_F_TEST_STATE_FREQ | 2036 BPF_F_TEST_RND_HI32)) 2037 return -EINVAL; 2038 2039 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2040 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2041 !capable(CAP_SYS_ADMIN)) 2042 return -EPERM; 2043 2044 /* copy eBPF program license from user space */ 2045 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 2046 sizeof(license) - 1) < 0) 2047 return -EFAULT; 2048 license[sizeof(license) - 1] = 0; 2049 2050 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2051 is_gpl = license_is_gpl_compatible(license); 2052 2053 if (attr->insn_cnt == 0 || 2054 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2055 return -E2BIG; 2056 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2057 type != BPF_PROG_TYPE_CGROUP_SKB && 2058 !capable(CAP_SYS_ADMIN)) 2059 return -EPERM; 2060 2061 bpf_prog_load_fixup_attach_type(attr); 2062 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2063 attr->attach_btf_id, 2064 attr->attach_prog_fd)) 2065 return -EINVAL; 2066 2067 /* plain bpf_prog allocation */ 2068 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2069 if (!prog) 2070 return -ENOMEM; 2071 2072 prog->expected_attach_type = attr->expected_attach_type; 2073 prog->aux->attach_btf_id = attr->attach_btf_id; 2074 if (attr->attach_prog_fd) { 2075 struct bpf_prog *tgt_prog; 2076 2077 tgt_prog = bpf_prog_get(attr->attach_prog_fd); 2078 if (IS_ERR(tgt_prog)) { 2079 err = PTR_ERR(tgt_prog); 2080 goto free_prog_nouncharge; 2081 } 2082 prog->aux->linked_prog = tgt_prog; 2083 } 2084 2085 prog->aux->offload_requested = !!attr->prog_ifindex; 2086 2087 err = security_bpf_prog_alloc(prog->aux); 2088 if (err) 2089 goto free_prog_nouncharge; 2090 2091 err = bpf_prog_charge_memlock(prog); 2092 if (err) 2093 goto free_prog_sec; 2094 2095 prog->len = attr->insn_cnt; 2096 2097 err = -EFAULT; 2098 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 2099 bpf_prog_insn_size(prog)) != 0) 2100 goto free_prog; 2101 2102 prog->orig_prog = NULL; 2103 prog->jited = 0; 2104 2105 atomic64_set(&prog->aux->refcnt, 1); 2106 prog->gpl_compatible = is_gpl ? 1 : 0; 2107 2108 if (bpf_prog_is_dev_bound(prog->aux)) { 2109 err = bpf_prog_offload_init(prog, attr); 2110 if (err) 2111 goto free_prog; 2112 } 2113 2114 /* find program type: socket_filter vs tracing_filter */ 2115 err = find_prog_type(type, prog); 2116 if (err < 0) 2117 goto free_prog; 2118 2119 prog->aux->load_time = ktime_get_boottime_ns(); 2120 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2121 sizeof(attr->prog_name)); 2122 if (err < 0) 2123 goto free_prog; 2124 2125 /* run eBPF verifier */ 2126 err = bpf_check(&prog, attr, uattr); 2127 if (err < 0) 2128 goto free_used_maps; 2129 2130 prog = bpf_prog_select_runtime(prog, &err); 2131 if (err < 0) 2132 goto free_used_maps; 2133 2134 err = bpf_prog_alloc_id(prog); 2135 if (err) 2136 goto free_used_maps; 2137 2138 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2139 * effectively publicly exposed. However, retrieving via 2140 * bpf_prog_get_fd_by_id() will take another reference, 2141 * therefore it cannot be gone underneath us. 2142 * 2143 * Only for the time /after/ successful bpf_prog_new_fd() 2144 * and before returning to userspace, we might just hold 2145 * one reference and any parallel close on that fd could 2146 * rip everything out. Hence, below notifications must 2147 * happen before bpf_prog_new_fd(). 2148 * 2149 * Also, any failure handling from this point onwards must 2150 * be using bpf_prog_put() given the program is exposed. 2151 */ 2152 bpf_prog_kallsyms_add(prog); 2153 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2154 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2155 2156 err = bpf_prog_new_fd(prog); 2157 if (err < 0) 2158 bpf_prog_put(prog); 2159 return err; 2160 2161 free_used_maps: 2162 /* In case we have subprogs, we need to wait for a grace 2163 * period before we can tear down JIT memory since symbols 2164 * are already exposed under kallsyms. 2165 */ 2166 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2167 return err; 2168 free_prog: 2169 bpf_prog_uncharge_memlock(prog); 2170 free_prog_sec: 2171 security_bpf_prog_free(prog->aux); 2172 free_prog_nouncharge: 2173 bpf_prog_free(prog); 2174 return err; 2175 } 2176 2177 #define BPF_OBJ_LAST_FIELD file_flags 2178 2179 static int bpf_obj_pin(const union bpf_attr *attr) 2180 { 2181 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2182 return -EINVAL; 2183 2184 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2185 } 2186 2187 static int bpf_obj_get(const union bpf_attr *attr) 2188 { 2189 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2190 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2191 return -EINVAL; 2192 2193 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2194 attr->file_flags); 2195 } 2196 2197 void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops, 2198 struct bpf_prog *prog) 2199 { 2200 atomic64_set(&link->refcnt, 1); 2201 link->ops = ops; 2202 link->prog = prog; 2203 } 2204 2205 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2206 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2207 * anon_inode's release() call. This helper manages marking bpf_link as 2208 * defunct, releases anon_inode file and puts reserved FD. 2209 */ 2210 void bpf_link_cleanup(struct bpf_link *link, struct file *link_file, 2211 int link_fd) 2212 { 2213 link->prog = NULL; 2214 fput(link_file); 2215 put_unused_fd(link_fd); 2216 } 2217 2218 void bpf_link_inc(struct bpf_link *link) 2219 { 2220 atomic64_inc(&link->refcnt); 2221 } 2222 2223 /* bpf_link_free is guaranteed to be called from process context */ 2224 static void bpf_link_free(struct bpf_link *link) 2225 { 2226 if (link->prog) { 2227 /* detach BPF program, clean up used resources */ 2228 link->ops->release(link); 2229 bpf_prog_put(link->prog); 2230 } 2231 /* free bpf_link and its containing memory */ 2232 link->ops->dealloc(link); 2233 } 2234 2235 static void bpf_link_put_deferred(struct work_struct *work) 2236 { 2237 struct bpf_link *link = container_of(work, struct bpf_link, work); 2238 2239 bpf_link_free(link); 2240 } 2241 2242 /* bpf_link_put can be called from atomic context, but ensures that resources 2243 * are freed from process context 2244 */ 2245 void bpf_link_put(struct bpf_link *link) 2246 { 2247 if (!atomic64_dec_and_test(&link->refcnt)) 2248 return; 2249 2250 if (in_atomic()) { 2251 INIT_WORK(&link->work, bpf_link_put_deferred); 2252 schedule_work(&link->work); 2253 } else { 2254 bpf_link_free(link); 2255 } 2256 } 2257 2258 static int bpf_link_release(struct inode *inode, struct file *filp) 2259 { 2260 struct bpf_link *link = filp->private_data; 2261 2262 bpf_link_put(link); 2263 return 0; 2264 } 2265 2266 #ifdef CONFIG_PROC_FS 2267 static const struct bpf_link_ops bpf_raw_tp_lops; 2268 static const struct bpf_link_ops bpf_tracing_link_lops; 2269 2270 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2271 { 2272 const struct bpf_link *link = filp->private_data; 2273 const struct bpf_prog *prog = link->prog; 2274 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2275 const char *link_type; 2276 2277 if (link->ops == &bpf_raw_tp_lops) 2278 link_type = "raw_tracepoint"; 2279 else if (link->ops == &bpf_tracing_link_lops) 2280 link_type = "tracing"; 2281 #ifdef CONFIG_CGROUP_BPF 2282 else if (link->ops == &bpf_cgroup_link_lops) 2283 link_type = "cgroup"; 2284 #endif 2285 else 2286 link_type = "unknown"; 2287 2288 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2289 seq_printf(m, 2290 "link_type:\t%s\n" 2291 "prog_tag:\t%s\n" 2292 "prog_id:\t%u\n", 2293 link_type, 2294 prog_tag, 2295 prog->aux->id); 2296 } 2297 #endif 2298 2299 static const struct file_operations bpf_link_fops = { 2300 #ifdef CONFIG_PROC_FS 2301 .show_fdinfo = bpf_link_show_fdinfo, 2302 #endif 2303 .release = bpf_link_release, 2304 .read = bpf_dummy_read, 2305 .write = bpf_dummy_write, 2306 }; 2307 2308 int bpf_link_new_fd(struct bpf_link *link) 2309 { 2310 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2311 } 2312 2313 /* Similar to bpf_link_new_fd, create anon_inode for given bpf_link, but 2314 * instead of immediately installing fd in fdtable, just reserve it and 2315 * return. Caller then need to either install it with fd_install(fd, file) or 2316 * release with put_unused_fd(fd). 2317 * This is useful for cases when bpf_link attachment/detachment are 2318 * complicated and expensive operations and should be delayed until all the fd 2319 * reservation and anon_inode creation succeeds. 2320 */ 2321 struct file *bpf_link_new_file(struct bpf_link *link, int *reserved_fd) 2322 { 2323 struct file *file; 2324 int fd; 2325 2326 fd = get_unused_fd_flags(O_CLOEXEC); 2327 if (fd < 0) 2328 return ERR_PTR(fd); 2329 2330 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2331 if (IS_ERR(file)) { 2332 put_unused_fd(fd); 2333 return file; 2334 } 2335 2336 *reserved_fd = fd; 2337 return file; 2338 } 2339 2340 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2341 { 2342 struct fd f = fdget(ufd); 2343 struct bpf_link *link; 2344 2345 if (!f.file) 2346 return ERR_PTR(-EBADF); 2347 if (f.file->f_op != &bpf_link_fops) { 2348 fdput(f); 2349 return ERR_PTR(-EINVAL); 2350 } 2351 2352 link = f.file->private_data; 2353 bpf_link_inc(link); 2354 fdput(f); 2355 2356 return link; 2357 } 2358 2359 struct bpf_tracing_link { 2360 struct bpf_link link; 2361 }; 2362 2363 static void bpf_tracing_link_release(struct bpf_link *link) 2364 { 2365 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog)); 2366 } 2367 2368 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2369 { 2370 struct bpf_tracing_link *tr_link = 2371 container_of(link, struct bpf_tracing_link, link); 2372 2373 kfree(tr_link); 2374 } 2375 2376 static const struct bpf_link_ops bpf_tracing_link_lops = { 2377 .release = bpf_tracing_link_release, 2378 .dealloc = bpf_tracing_link_dealloc, 2379 }; 2380 2381 static int bpf_tracing_prog_attach(struct bpf_prog *prog) 2382 { 2383 struct bpf_tracing_link *link; 2384 struct file *link_file; 2385 int link_fd, err; 2386 2387 switch (prog->type) { 2388 case BPF_PROG_TYPE_TRACING: 2389 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2390 prog->expected_attach_type != BPF_TRACE_FEXIT && 2391 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2392 err = -EINVAL; 2393 goto out_put_prog; 2394 } 2395 break; 2396 case BPF_PROG_TYPE_EXT: 2397 if (prog->expected_attach_type != 0) { 2398 err = -EINVAL; 2399 goto out_put_prog; 2400 } 2401 break; 2402 case BPF_PROG_TYPE_LSM: 2403 if (prog->expected_attach_type != BPF_LSM_MAC) { 2404 err = -EINVAL; 2405 goto out_put_prog; 2406 } 2407 break; 2408 default: 2409 err = -EINVAL; 2410 goto out_put_prog; 2411 } 2412 2413 link = kzalloc(sizeof(*link), GFP_USER); 2414 if (!link) { 2415 err = -ENOMEM; 2416 goto out_put_prog; 2417 } 2418 bpf_link_init(&link->link, &bpf_tracing_link_lops, prog); 2419 2420 link_file = bpf_link_new_file(&link->link, &link_fd); 2421 if (IS_ERR(link_file)) { 2422 kfree(link); 2423 err = PTR_ERR(link_file); 2424 goto out_put_prog; 2425 } 2426 2427 err = bpf_trampoline_link_prog(prog); 2428 if (err) { 2429 bpf_link_cleanup(&link->link, link_file, link_fd); 2430 goto out_put_prog; 2431 } 2432 2433 fd_install(link_fd, link_file); 2434 return link_fd; 2435 2436 out_put_prog: 2437 bpf_prog_put(prog); 2438 return err; 2439 } 2440 2441 struct bpf_raw_tp_link { 2442 struct bpf_link link; 2443 struct bpf_raw_event_map *btp; 2444 }; 2445 2446 static void bpf_raw_tp_link_release(struct bpf_link *link) 2447 { 2448 struct bpf_raw_tp_link *raw_tp = 2449 container_of(link, struct bpf_raw_tp_link, link); 2450 2451 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2452 bpf_put_raw_tracepoint(raw_tp->btp); 2453 } 2454 2455 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2456 { 2457 struct bpf_raw_tp_link *raw_tp = 2458 container_of(link, struct bpf_raw_tp_link, link); 2459 2460 kfree(raw_tp); 2461 } 2462 2463 static const struct bpf_link_ops bpf_raw_tp_lops = { 2464 .release = bpf_raw_tp_link_release, 2465 .dealloc = bpf_raw_tp_link_dealloc, 2466 }; 2467 2468 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 2469 2470 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 2471 { 2472 struct bpf_raw_tp_link *link; 2473 struct bpf_raw_event_map *btp; 2474 struct file *link_file; 2475 struct bpf_prog *prog; 2476 const char *tp_name; 2477 char buf[128]; 2478 int link_fd, err; 2479 2480 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 2481 return -EINVAL; 2482 2483 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 2484 if (IS_ERR(prog)) 2485 return PTR_ERR(prog); 2486 2487 switch (prog->type) { 2488 case BPF_PROG_TYPE_TRACING: 2489 case BPF_PROG_TYPE_EXT: 2490 case BPF_PROG_TYPE_LSM: 2491 if (attr->raw_tracepoint.name) { 2492 /* The attach point for this category of programs 2493 * should be specified via btf_id during program load. 2494 */ 2495 err = -EINVAL; 2496 goto out_put_prog; 2497 } 2498 if (prog->type == BPF_PROG_TYPE_TRACING && 2499 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 2500 tp_name = prog->aux->attach_func_name; 2501 break; 2502 } 2503 return bpf_tracing_prog_attach(prog); 2504 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2505 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2506 if (strncpy_from_user(buf, 2507 u64_to_user_ptr(attr->raw_tracepoint.name), 2508 sizeof(buf) - 1) < 0) { 2509 err = -EFAULT; 2510 goto out_put_prog; 2511 } 2512 buf[sizeof(buf) - 1] = 0; 2513 tp_name = buf; 2514 break; 2515 default: 2516 err = -EINVAL; 2517 goto out_put_prog; 2518 } 2519 2520 btp = bpf_get_raw_tracepoint(tp_name); 2521 if (!btp) { 2522 err = -ENOENT; 2523 goto out_put_prog; 2524 } 2525 2526 link = kzalloc(sizeof(*link), GFP_USER); 2527 if (!link) { 2528 err = -ENOMEM; 2529 goto out_put_btp; 2530 } 2531 bpf_link_init(&link->link, &bpf_raw_tp_lops, prog); 2532 link->btp = btp; 2533 2534 link_file = bpf_link_new_file(&link->link, &link_fd); 2535 if (IS_ERR(link_file)) { 2536 kfree(link); 2537 err = PTR_ERR(link_file); 2538 goto out_put_btp; 2539 } 2540 2541 err = bpf_probe_register(link->btp, prog); 2542 if (err) { 2543 bpf_link_cleanup(&link->link, link_file, link_fd); 2544 goto out_put_btp; 2545 } 2546 2547 fd_install(link_fd, link_file); 2548 return link_fd; 2549 2550 out_put_btp: 2551 bpf_put_raw_tracepoint(btp); 2552 out_put_prog: 2553 bpf_prog_put(prog); 2554 return err; 2555 } 2556 2557 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 2558 enum bpf_attach_type attach_type) 2559 { 2560 switch (prog->type) { 2561 case BPF_PROG_TYPE_CGROUP_SOCK: 2562 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2563 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2564 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 2565 case BPF_PROG_TYPE_CGROUP_SKB: 2566 return prog->enforce_expected_attach_type && 2567 prog->expected_attach_type != attach_type ? 2568 -EINVAL : 0; 2569 default: 2570 return 0; 2571 } 2572 } 2573 2574 static enum bpf_prog_type 2575 attach_type_to_prog_type(enum bpf_attach_type attach_type) 2576 { 2577 switch (attach_type) { 2578 case BPF_CGROUP_INET_INGRESS: 2579 case BPF_CGROUP_INET_EGRESS: 2580 return BPF_PROG_TYPE_CGROUP_SKB; 2581 break; 2582 case BPF_CGROUP_INET_SOCK_CREATE: 2583 case BPF_CGROUP_INET4_POST_BIND: 2584 case BPF_CGROUP_INET6_POST_BIND: 2585 return BPF_PROG_TYPE_CGROUP_SOCK; 2586 case BPF_CGROUP_INET4_BIND: 2587 case BPF_CGROUP_INET6_BIND: 2588 case BPF_CGROUP_INET4_CONNECT: 2589 case BPF_CGROUP_INET6_CONNECT: 2590 case BPF_CGROUP_UDP4_SENDMSG: 2591 case BPF_CGROUP_UDP6_SENDMSG: 2592 case BPF_CGROUP_UDP4_RECVMSG: 2593 case BPF_CGROUP_UDP6_RECVMSG: 2594 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 2595 case BPF_CGROUP_SOCK_OPS: 2596 return BPF_PROG_TYPE_SOCK_OPS; 2597 case BPF_CGROUP_DEVICE: 2598 return BPF_PROG_TYPE_CGROUP_DEVICE; 2599 case BPF_SK_MSG_VERDICT: 2600 return BPF_PROG_TYPE_SK_MSG; 2601 case BPF_SK_SKB_STREAM_PARSER: 2602 case BPF_SK_SKB_STREAM_VERDICT: 2603 return BPF_PROG_TYPE_SK_SKB; 2604 case BPF_LIRC_MODE2: 2605 return BPF_PROG_TYPE_LIRC_MODE2; 2606 case BPF_FLOW_DISSECTOR: 2607 return BPF_PROG_TYPE_FLOW_DISSECTOR; 2608 case BPF_CGROUP_SYSCTL: 2609 return BPF_PROG_TYPE_CGROUP_SYSCTL; 2610 case BPF_CGROUP_GETSOCKOPT: 2611 case BPF_CGROUP_SETSOCKOPT: 2612 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 2613 default: 2614 return BPF_PROG_TYPE_UNSPEC; 2615 } 2616 } 2617 2618 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 2619 2620 #define BPF_F_ATTACH_MASK \ 2621 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 2622 2623 static int bpf_prog_attach(const union bpf_attr *attr) 2624 { 2625 enum bpf_prog_type ptype; 2626 struct bpf_prog *prog; 2627 int ret; 2628 2629 if (!capable(CAP_NET_ADMIN)) 2630 return -EPERM; 2631 2632 if (CHECK_ATTR(BPF_PROG_ATTACH)) 2633 return -EINVAL; 2634 2635 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 2636 return -EINVAL; 2637 2638 ptype = attach_type_to_prog_type(attr->attach_type); 2639 if (ptype == BPF_PROG_TYPE_UNSPEC) 2640 return -EINVAL; 2641 2642 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 2643 if (IS_ERR(prog)) 2644 return PTR_ERR(prog); 2645 2646 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 2647 bpf_prog_put(prog); 2648 return -EINVAL; 2649 } 2650 2651 switch (ptype) { 2652 case BPF_PROG_TYPE_SK_SKB: 2653 case BPF_PROG_TYPE_SK_MSG: 2654 ret = sock_map_get_from_fd(attr, prog); 2655 break; 2656 case BPF_PROG_TYPE_LIRC_MODE2: 2657 ret = lirc_prog_attach(attr, prog); 2658 break; 2659 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2660 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 2661 break; 2662 case BPF_PROG_TYPE_CGROUP_DEVICE: 2663 case BPF_PROG_TYPE_CGROUP_SKB: 2664 case BPF_PROG_TYPE_CGROUP_SOCK: 2665 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2666 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2667 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2668 case BPF_PROG_TYPE_SOCK_OPS: 2669 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 2670 break; 2671 default: 2672 ret = -EINVAL; 2673 } 2674 2675 if (ret) 2676 bpf_prog_put(prog); 2677 return ret; 2678 } 2679 2680 #define BPF_PROG_DETACH_LAST_FIELD attach_type 2681 2682 static int bpf_prog_detach(const union bpf_attr *attr) 2683 { 2684 enum bpf_prog_type ptype; 2685 2686 if (!capable(CAP_NET_ADMIN)) 2687 return -EPERM; 2688 2689 if (CHECK_ATTR(BPF_PROG_DETACH)) 2690 return -EINVAL; 2691 2692 ptype = attach_type_to_prog_type(attr->attach_type); 2693 2694 switch (ptype) { 2695 case BPF_PROG_TYPE_SK_MSG: 2696 case BPF_PROG_TYPE_SK_SKB: 2697 return sock_map_get_from_fd(attr, NULL); 2698 case BPF_PROG_TYPE_LIRC_MODE2: 2699 return lirc_prog_detach(attr); 2700 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2701 return skb_flow_dissector_bpf_prog_detach(attr); 2702 case BPF_PROG_TYPE_CGROUP_DEVICE: 2703 case BPF_PROG_TYPE_CGROUP_SKB: 2704 case BPF_PROG_TYPE_CGROUP_SOCK: 2705 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2706 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2707 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2708 case BPF_PROG_TYPE_SOCK_OPS: 2709 return cgroup_bpf_prog_detach(attr, ptype); 2710 default: 2711 return -EINVAL; 2712 } 2713 } 2714 2715 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 2716 2717 static int bpf_prog_query(const union bpf_attr *attr, 2718 union bpf_attr __user *uattr) 2719 { 2720 if (!capable(CAP_NET_ADMIN)) 2721 return -EPERM; 2722 if (CHECK_ATTR(BPF_PROG_QUERY)) 2723 return -EINVAL; 2724 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2725 return -EINVAL; 2726 2727 switch (attr->query.attach_type) { 2728 case BPF_CGROUP_INET_INGRESS: 2729 case BPF_CGROUP_INET_EGRESS: 2730 case BPF_CGROUP_INET_SOCK_CREATE: 2731 case BPF_CGROUP_INET4_BIND: 2732 case BPF_CGROUP_INET6_BIND: 2733 case BPF_CGROUP_INET4_POST_BIND: 2734 case BPF_CGROUP_INET6_POST_BIND: 2735 case BPF_CGROUP_INET4_CONNECT: 2736 case BPF_CGROUP_INET6_CONNECT: 2737 case BPF_CGROUP_UDP4_SENDMSG: 2738 case BPF_CGROUP_UDP6_SENDMSG: 2739 case BPF_CGROUP_UDP4_RECVMSG: 2740 case BPF_CGROUP_UDP6_RECVMSG: 2741 case BPF_CGROUP_SOCK_OPS: 2742 case BPF_CGROUP_DEVICE: 2743 case BPF_CGROUP_SYSCTL: 2744 case BPF_CGROUP_GETSOCKOPT: 2745 case BPF_CGROUP_SETSOCKOPT: 2746 return cgroup_bpf_prog_query(attr, uattr); 2747 case BPF_LIRC_MODE2: 2748 return lirc_prog_query(attr, uattr); 2749 case BPF_FLOW_DISSECTOR: 2750 return skb_flow_dissector_prog_query(attr, uattr); 2751 default: 2752 return -EINVAL; 2753 } 2754 } 2755 2756 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2757 2758 static int bpf_prog_test_run(const union bpf_attr *attr, 2759 union bpf_attr __user *uattr) 2760 { 2761 struct bpf_prog *prog; 2762 int ret = -ENOTSUPP; 2763 2764 if (!capable(CAP_SYS_ADMIN)) 2765 return -EPERM; 2766 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2767 return -EINVAL; 2768 2769 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2770 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2771 return -EINVAL; 2772 2773 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2774 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2775 return -EINVAL; 2776 2777 prog = bpf_prog_get(attr->test.prog_fd); 2778 if (IS_ERR(prog)) 2779 return PTR_ERR(prog); 2780 2781 if (prog->aux->ops->test_run) 2782 ret = prog->aux->ops->test_run(prog, attr, uattr); 2783 2784 bpf_prog_put(prog); 2785 return ret; 2786 } 2787 2788 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2789 2790 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2791 union bpf_attr __user *uattr, 2792 struct idr *idr, 2793 spinlock_t *lock) 2794 { 2795 u32 next_id = attr->start_id; 2796 int err = 0; 2797 2798 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2799 return -EINVAL; 2800 2801 if (!capable(CAP_SYS_ADMIN)) 2802 return -EPERM; 2803 2804 next_id++; 2805 spin_lock_bh(lock); 2806 if (!idr_get_next(idr, &next_id)) 2807 err = -ENOENT; 2808 spin_unlock_bh(lock); 2809 2810 if (!err) 2811 err = put_user(next_id, &uattr->next_id); 2812 2813 return err; 2814 } 2815 2816 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2817 2818 struct bpf_prog *bpf_prog_by_id(u32 id) 2819 { 2820 struct bpf_prog *prog; 2821 2822 if (!id) 2823 return ERR_PTR(-ENOENT); 2824 2825 spin_lock_bh(&prog_idr_lock); 2826 prog = idr_find(&prog_idr, id); 2827 if (prog) 2828 prog = bpf_prog_inc_not_zero(prog); 2829 else 2830 prog = ERR_PTR(-ENOENT); 2831 spin_unlock_bh(&prog_idr_lock); 2832 return prog; 2833 } 2834 2835 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2836 { 2837 struct bpf_prog *prog; 2838 u32 id = attr->prog_id; 2839 int fd; 2840 2841 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2842 return -EINVAL; 2843 2844 if (!capable(CAP_SYS_ADMIN)) 2845 return -EPERM; 2846 2847 prog = bpf_prog_by_id(id); 2848 if (IS_ERR(prog)) 2849 return PTR_ERR(prog); 2850 2851 fd = bpf_prog_new_fd(prog); 2852 if (fd < 0) 2853 bpf_prog_put(prog); 2854 2855 return fd; 2856 } 2857 2858 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2859 2860 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2861 { 2862 struct bpf_map *map; 2863 u32 id = attr->map_id; 2864 int f_flags; 2865 int fd; 2866 2867 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2868 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2869 return -EINVAL; 2870 2871 if (!capable(CAP_SYS_ADMIN)) 2872 return -EPERM; 2873 2874 f_flags = bpf_get_file_flag(attr->open_flags); 2875 if (f_flags < 0) 2876 return f_flags; 2877 2878 spin_lock_bh(&map_idr_lock); 2879 map = idr_find(&map_idr, id); 2880 if (map) 2881 map = __bpf_map_inc_not_zero(map, true); 2882 else 2883 map = ERR_PTR(-ENOENT); 2884 spin_unlock_bh(&map_idr_lock); 2885 2886 if (IS_ERR(map)) 2887 return PTR_ERR(map); 2888 2889 fd = bpf_map_new_fd(map, f_flags); 2890 if (fd < 0) 2891 bpf_map_put_with_uref(map); 2892 2893 return fd; 2894 } 2895 2896 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2897 unsigned long addr, u32 *off, 2898 u32 *type) 2899 { 2900 const struct bpf_map *map; 2901 int i; 2902 2903 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2904 map = prog->aux->used_maps[i]; 2905 if (map == (void *)addr) { 2906 *type = BPF_PSEUDO_MAP_FD; 2907 return map; 2908 } 2909 if (!map->ops->map_direct_value_meta) 2910 continue; 2911 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2912 *type = BPF_PSEUDO_MAP_VALUE; 2913 return map; 2914 } 2915 } 2916 2917 return NULL; 2918 } 2919 2920 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2921 { 2922 const struct bpf_map *map; 2923 struct bpf_insn *insns; 2924 u32 off, type; 2925 u64 imm; 2926 int i; 2927 2928 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2929 GFP_USER); 2930 if (!insns) 2931 return insns; 2932 2933 for (i = 0; i < prog->len; i++) { 2934 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2935 insns[i].code = BPF_JMP | BPF_CALL; 2936 insns[i].imm = BPF_FUNC_tail_call; 2937 /* fall-through */ 2938 } 2939 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2940 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2941 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2942 insns[i].code = BPF_JMP | BPF_CALL; 2943 if (!bpf_dump_raw_ok()) 2944 insns[i].imm = 0; 2945 continue; 2946 } 2947 2948 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2949 continue; 2950 2951 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2952 map = bpf_map_from_imm(prog, imm, &off, &type); 2953 if (map) { 2954 insns[i].src_reg = type; 2955 insns[i].imm = map->id; 2956 insns[i + 1].imm = off; 2957 continue; 2958 } 2959 } 2960 2961 return insns; 2962 } 2963 2964 static int set_info_rec_size(struct bpf_prog_info *info) 2965 { 2966 /* 2967 * Ensure info.*_rec_size is the same as kernel expected size 2968 * 2969 * or 2970 * 2971 * Only allow zero *_rec_size if both _rec_size and _cnt are 2972 * zero. In this case, the kernel will set the expected 2973 * _rec_size back to the info. 2974 */ 2975 2976 if ((info->nr_func_info || info->func_info_rec_size) && 2977 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2978 return -EINVAL; 2979 2980 if ((info->nr_line_info || info->line_info_rec_size) && 2981 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2982 return -EINVAL; 2983 2984 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2985 info->jited_line_info_rec_size != sizeof(__u64)) 2986 return -EINVAL; 2987 2988 info->func_info_rec_size = sizeof(struct bpf_func_info); 2989 info->line_info_rec_size = sizeof(struct bpf_line_info); 2990 info->jited_line_info_rec_size = sizeof(__u64); 2991 2992 return 0; 2993 } 2994 2995 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2996 const union bpf_attr *attr, 2997 union bpf_attr __user *uattr) 2998 { 2999 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3000 struct bpf_prog_info info; 3001 u32 info_len = attr->info.info_len; 3002 struct bpf_prog_stats stats; 3003 char __user *uinsns; 3004 u32 ulen; 3005 int err; 3006 3007 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 3008 if (err) 3009 return err; 3010 info_len = min_t(u32, sizeof(info), info_len); 3011 3012 memset(&info, 0, sizeof(info)); 3013 if (copy_from_user(&info, uinfo, info_len)) 3014 return -EFAULT; 3015 3016 info.type = prog->type; 3017 info.id = prog->aux->id; 3018 info.load_time = prog->aux->load_time; 3019 info.created_by_uid = from_kuid_munged(current_user_ns(), 3020 prog->aux->user->uid); 3021 info.gpl_compatible = prog->gpl_compatible; 3022 3023 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3024 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3025 3026 ulen = info.nr_map_ids; 3027 info.nr_map_ids = prog->aux->used_map_cnt; 3028 ulen = min_t(u32, info.nr_map_ids, ulen); 3029 if (ulen) { 3030 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3031 u32 i; 3032 3033 for (i = 0; i < ulen; i++) 3034 if (put_user(prog->aux->used_maps[i]->id, 3035 &user_map_ids[i])) 3036 return -EFAULT; 3037 } 3038 3039 err = set_info_rec_size(&info); 3040 if (err) 3041 return err; 3042 3043 bpf_prog_get_stats(prog, &stats); 3044 info.run_time_ns = stats.nsecs; 3045 info.run_cnt = stats.cnt; 3046 3047 if (!capable(CAP_SYS_ADMIN)) { 3048 info.jited_prog_len = 0; 3049 info.xlated_prog_len = 0; 3050 info.nr_jited_ksyms = 0; 3051 info.nr_jited_func_lens = 0; 3052 info.nr_func_info = 0; 3053 info.nr_line_info = 0; 3054 info.nr_jited_line_info = 0; 3055 goto done; 3056 } 3057 3058 ulen = info.xlated_prog_len; 3059 info.xlated_prog_len = bpf_prog_insn_size(prog); 3060 if (info.xlated_prog_len && ulen) { 3061 struct bpf_insn *insns_sanitized; 3062 bool fault; 3063 3064 if (prog->blinded && !bpf_dump_raw_ok()) { 3065 info.xlated_prog_insns = 0; 3066 goto done; 3067 } 3068 insns_sanitized = bpf_insn_prepare_dump(prog); 3069 if (!insns_sanitized) 3070 return -ENOMEM; 3071 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3072 ulen = min_t(u32, info.xlated_prog_len, ulen); 3073 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3074 kfree(insns_sanitized); 3075 if (fault) 3076 return -EFAULT; 3077 } 3078 3079 if (bpf_prog_is_dev_bound(prog->aux)) { 3080 err = bpf_prog_offload_info_fill(&info, prog); 3081 if (err) 3082 return err; 3083 goto done; 3084 } 3085 3086 /* NOTE: the following code is supposed to be skipped for offload. 3087 * bpf_prog_offload_info_fill() is the place to fill similar fields 3088 * for offload. 3089 */ 3090 ulen = info.jited_prog_len; 3091 if (prog->aux->func_cnt) { 3092 u32 i; 3093 3094 info.jited_prog_len = 0; 3095 for (i = 0; i < prog->aux->func_cnt; i++) 3096 info.jited_prog_len += prog->aux->func[i]->jited_len; 3097 } else { 3098 info.jited_prog_len = prog->jited_len; 3099 } 3100 3101 if (info.jited_prog_len && ulen) { 3102 if (bpf_dump_raw_ok()) { 3103 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3104 ulen = min_t(u32, info.jited_prog_len, ulen); 3105 3106 /* for multi-function programs, copy the JITed 3107 * instructions for all the functions 3108 */ 3109 if (prog->aux->func_cnt) { 3110 u32 len, free, i; 3111 u8 *img; 3112 3113 free = ulen; 3114 for (i = 0; i < prog->aux->func_cnt; i++) { 3115 len = prog->aux->func[i]->jited_len; 3116 len = min_t(u32, len, free); 3117 img = (u8 *) prog->aux->func[i]->bpf_func; 3118 if (copy_to_user(uinsns, img, len)) 3119 return -EFAULT; 3120 uinsns += len; 3121 free -= len; 3122 if (!free) 3123 break; 3124 } 3125 } else { 3126 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3127 return -EFAULT; 3128 } 3129 } else { 3130 info.jited_prog_insns = 0; 3131 } 3132 } 3133 3134 ulen = info.nr_jited_ksyms; 3135 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3136 if (ulen) { 3137 if (bpf_dump_raw_ok()) { 3138 unsigned long ksym_addr; 3139 u64 __user *user_ksyms; 3140 u32 i; 3141 3142 /* copy the address of the kernel symbol 3143 * corresponding to each function 3144 */ 3145 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3146 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3147 if (prog->aux->func_cnt) { 3148 for (i = 0; i < ulen; i++) { 3149 ksym_addr = (unsigned long) 3150 prog->aux->func[i]->bpf_func; 3151 if (put_user((u64) ksym_addr, 3152 &user_ksyms[i])) 3153 return -EFAULT; 3154 } 3155 } else { 3156 ksym_addr = (unsigned long) prog->bpf_func; 3157 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3158 return -EFAULT; 3159 } 3160 } else { 3161 info.jited_ksyms = 0; 3162 } 3163 } 3164 3165 ulen = info.nr_jited_func_lens; 3166 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3167 if (ulen) { 3168 if (bpf_dump_raw_ok()) { 3169 u32 __user *user_lens; 3170 u32 func_len, i; 3171 3172 /* copy the JITed image lengths for each function */ 3173 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3174 user_lens = u64_to_user_ptr(info.jited_func_lens); 3175 if (prog->aux->func_cnt) { 3176 for (i = 0; i < ulen; i++) { 3177 func_len = 3178 prog->aux->func[i]->jited_len; 3179 if (put_user(func_len, &user_lens[i])) 3180 return -EFAULT; 3181 } 3182 } else { 3183 func_len = prog->jited_len; 3184 if (put_user(func_len, &user_lens[0])) 3185 return -EFAULT; 3186 } 3187 } else { 3188 info.jited_func_lens = 0; 3189 } 3190 } 3191 3192 if (prog->aux->btf) 3193 info.btf_id = btf_id(prog->aux->btf); 3194 3195 ulen = info.nr_func_info; 3196 info.nr_func_info = prog->aux->func_info_cnt; 3197 if (info.nr_func_info && ulen) { 3198 char __user *user_finfo; 3199 3200 user_finfo = u64_to_user_ptr(info.func_info); 3201 ulen = min_t(u32, info.nr_func_info, ulen); 3202 if (copy_to_user(user_finfo, prog->aux->func_info, 3203 info.func_info_rec_size * ulen)) 3204 return -EFAULT; 3205 } 3206 3207 ulen = info.nr_line_info; 3208 info.nr_line_info = prog->aux->nr_linfo; 3209 if (info.nr_line_info && ulen) { 3210 __u8 __user *user_linfo; 3211 3212 user_linfo = u64_to_user_ptr(info.line_info); 3213 ulen = min_t(u32, info.nr_line_info, ulen); 3214 if (copy_to_user(user_linfo, prog->aux->linfo, 3215 info.line_info_rec_size * ulen)) 3216 return -EFAULT; 3217 } 3218 3219 ulen = info.nr_jited_line_info; 3220 if (prog->aux->jited_linfo) 3221 info.nr_jited_line_info = prog->aux->nr_linfo; 3222 else 3223 info.nr_jited_line_info = 0; 3224 if (info.nr_jited_line_info && ulen) { 3225 if (bpf_dump_raw_ok()) { 3226 __u64 __user *user_linfo; 3227 u32 i; 3228 3229 user_linfo = u64_to_user_ptr(info.jited_line_info); 3230 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3231 for (i = 0; i < ulen; i++) { 3232 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3233 &user_linfo[i])) 3234 return -EFAULT; 3235 } 3236 } else { 3237 info.jited_line_info = 0; 3238 } 3239 } 3240 3241 ulen = info.nr_prog_tags; 3242 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3243 if (ulen) { 3244 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3245 u32 i; 3246 3247 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3248 ulen = min_t(u32, info.nr_prog_tags, ulen); 3249 if (prog->aux->func_cnt) { 3250 for (i = 0; i < ulen; i++) { 3251 if (copy_to_user(user_prog_tags[i], 3252 prog->aux->func[i]->tag, 3253 BPF_TAG_SIZE)) 3254 return -EFAULT; 3255 } 3256 } else { 3257 if (copy_to_user(user_prog_tags[0], 3258 prog->tag, BPF_TAG_SIZE)) 3259 return -EFAULT; 3260 } 3261 } 3262 3263 done: 3264 if (copy_to_user(uinfo, &info, info_len) || 3265 put_user(info_len, &uattr->info.info_len)) 3266 return -EFAULT; 3267 3268 return 0; 3269 } 3270 3271 static int bpf_map_get_info_by_fd(struct bpf_map *map, 3272 const union bpf_attr *attr, 3273 union bpf_attr __user *uattr) 3274 { 3275 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3276 struct bpf_map_info info; 3277 u32 info_len = attr->info.info_len; 3278 int err; 3279 3280 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 3281 if (err) 3282 return err; 3283 info_len = min_t(u32, sizeof(info), info_len); 3284 3285 memset(&info, 0, sizeof(info)); 3286 info.type = map->map_type; 3287 info.id = map->id; 3288 info.key_size = map->key_size; 3289 info.value_size = map->value_size; 3290 info.max_entries = map->max_entries; 3291 info.map_flags = map->map_flags; 3292 memcpy(info.name, map->name, sizeof(map->name)); 3293 3294 if (map->btf) { 3295 info.btf_id = btf_id(map->btf); 3296 info.btf_key_type_id = map->btf_key_type_id; 3297 info.btf_value_type_id = map->btf_value_type_id; 3298 } 3299 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3300 3301 if (bpf_map_is_dev_bound(map)) { 3302 err = bpf_map_offload_info_fill(&info, map); 3303 if (err) 3304 return err; 3305 } 3306 3307 if (copy_to_user(uinfo, &info, info_len) || 3308 put_user(info_len, &uattr->info.info_len)) 3309 return -EFAULT; 3310 3311 return 0; 3312 } 3313 3314 static int bpf_btf_get_info_by_fd(struct btf *btf, 3315 const union bpf_attr *attr, 3316 union bpf_attr __user *uattr) 3317 { 3318 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3319 u32 info_len = attr->info.info_len; 3320 int err; 3321 3322 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 3323 if (err) 3324 return err; 3325 3326 return btf_get_info_by_fd(btf, attr, uattr); 3327 } 3328 3329 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 3330 3331 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 3332 union bpf_attr __user *uattr) 3333 { 3334 int ufd = attr->info.bpf_fd; 3335 struct fd f; 3336 int err; 3337 3338 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 3339 return -EINVAL; 3340 3341 f = fdget(ufd); 3342 if (!f.file) 3343 return -EBADFD; 3344 3345 if (f.file->f_op == &bpf_prog_fops) 3346 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 3347 uattr); 3348 else if (f.file->f_op == &bpf_map_fops) 3349 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 3350 uattr); 3351 else if (f.file->f_op == &btf_fops) 3352 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 3353 else 3354 err = -EINVAL; 3355 3356 fdput(f); 3357 return err; 3358 } 3359 3360 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 3361 3362 static int bpf_btf_load(const union bpf_attr *attr) 3363 { 3364 if (CHECK_ATTR(BPF_BTF_LOAD)) 3365 return -EINVAL; 3366 3367 if (!capable(CAP_SYS_ADMIN)) 3368 return -EPERM; 3369 3370 return btf_new_fd(attr); 3371 } 3372 3373 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 3374 3375 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 3376 { 3377 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 3378 return -EINVAL; 3379 3380 if (!capable(CAP_SYS_ADMIN)) 3381 return -EPERM; 3382 3383 return btf_get_fd_by_id(attr->btf_id); 3384 } 3385 3386 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 3387 union bpf_attr __user *uattr, 3388 u32 prog_id, u32 fd_type, 3389 const char *buf, u64 probe_offset, 3390 u64 probe_addr) 3391 { 3392 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 3393 u32 len = buf ? strlen(buf) : 0, input_len; 3394 int err = 0; 3395 3396 if (put_user(len, &uattr->task_fd_query.buf_len)) 3397 return -EFAULT; 3398 input_len = attr->task_fd_query.buf_len; 3399 if (input_len && ubuf) { 3400 if (!len) { 3401 /* nothing to copy, just make ubuf NULL terminated */ 3402 char zero = '\0'; 3403 3404 if (put_user(zero, ubuf)) 3405 return -EFAULT; 3406 } else if (input_len >= len + 1) { 3407 /* ubuf can hold the string with NULL terminator */ 3408 if (copy_to_user(ubuf, buf, len + 1)) 3409 return -EFAULT; 3410 } else { 3411 /* ubuf cannot hold the string with NULL terminator, 3412 * do a partial copy with NULL terminator. 3413 */ 3414 char zero = '\0'; 3415 3416 err = -ENOSPC; 3417 if (copy_to_user(ubuf, buf, input_len - 1)) 3418 return -EFAULT; 3419 if (put_user(zero, ubuf + input_len - 1)) 3420 return -EFAULT; 3421 } 3422 } 3423 3424 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 3425 put_user(fd_type, &uattr->task_fd_query.fd_type) || 3426 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 3427 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 3428 return -EFAULT; 3429 3430 return err; 3431 } 3432 3433 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 3434 3435 static int bpf_task_fd_query(const union bpf_attr *attr, 3436 union bpf_attr __user *uattr) 3437 { 3438 pid_t pid = attr->task_fd_query.pid; 3439 u32 fd = attr->task_fd_query.fd; 3440 const struct perf_event *event; 3441 struct files_struct *files; 3442 struct task_struct *task; 3443 struct file *file; 3444 int err; 3445 3446 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 3447 return -EINVAL; 3448 3449 if (!capable(CAP_SYS_ADMIN)) 3450 return -EPERM; 3451 3452 if (attr->task_fd_query.flags != 0) 3453 return -EINVAL; 3454 3455 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 3456 if (!task) 3457 return -ENOENT; 3458 3459 files = get_files_struct(task); 3460 put_task_struct(task); 3461 if (!files) 3462 return -ENOENT; 3463 3464 err = 0; 3465 spin_lock(&files->file_lock); 3466 file = fcheck_files(files, fd); 3467 if (!file) 3468 err = -EBADF; 3469 else 3470 get_file(file); 3471 spin_unlock(&files->file_lock); 3472 put_files_struct(files); 3473 3474 if (err) 3475 goto out; 3476 3477 if (file->f_op == &bpf_link_fops) { 3478 struct bpf_link *link = file->private_data; 3479 3480 if (link->ops == &bpf_raw_tp_lops) { 3481 struct bpf_raw_tp_link *raw_tp = 3482 container_of(link, struct bpf_raw_tp_link, link); 3483 struct bpf_raw_event_map *btp = raw_tp->btp; 3484 3485 err = bpf_task_fd_query_copy(attr, uattr, 3486 raw_tp->link.prog->aux->id, 3487 BPF_FD_TYPE_RAW_TRACEPOINT, 3488 btp->tp->name, 0, 0); 3489 goto put_file; 3490 } 3491 goto out_not_supp; 3492 } 3493 3494 event = perf_get_event(file); 3495 if (!IS_ERR(event)) { 3496 u64 probe_offset, probe_addr; 3497 u32 prog_id, fd_type; 3498 const char *buf; 3499 3500 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 3501 &buf, &probe_offset, 3502 &probe_addr); 3503 if (!err) 3504 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 3505 fd_type, buf, 3506 probe_offset, 3507 probe_addr); 3508 goto put_file; 3509 } 3510 3511 out_not_supp: 3512 err = -ENOTSUPP; 3513 put_file: 3514 fput(file); 3515 out: 3516 return err; 3517 } 3518 3519 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 3520 3521 #define BPF_DO_BATCH(fn) \ 3522 do { \ 3523 if (!fn) { \ 3524 err = -ENOTSUPP; \ 3525 goto err_put; \ 3526 } \ 3527 err = fn(map, attr, uattr); \ 3528 } while (0) 3529 3530 static int bpf_map_do_batch(const union bpf_attr *attr, 3531 union bpf_attr __user *uattr, 3532 int cmd) 3533 { 3534 struct bpf_map *map; 3535 int err, ufd; 3536 struct fd f; 3537 3538 if (CHECK_ATTR(BPF_MAP_BATCH)) 3539 return -EINVAL; 3540 3541 ufd = attr->batch.map_fd; 3542 f = fdget(ufd); 3543 map = __bpf_map_get(f); 3544 if (IS_ERR(map)) 3545 return PTR_ERR(map); 3546 3547 if ((cmd == BPF_MAP_LOOKUP_BATCH || 3548 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) && 3549 !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 3550 err = -EPERM; 3551 goto err_put; 3552 } 3553 3554 if (cmd != BPF_MAP_LOOKUP_BATCH && 3555 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 3556 err = -EPERM; 3557 goto err_put; 3558 } 3559 3560 if (cmd == BPF_MAP_LOOKUP_BATCH) 3561 BPF_DO_BATCH(map->ops->map_lookup_batch); 3562 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 3563 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 3564 else if (cmd == BPF_MAP_UPDATE_BATCH) 3565 BPF_DO_BATCH(map->ops->map_update_batch); 3566 else 3567 BPF_DO_BATCH(map->ops->map_delete_batch); 3568 3569 err_put: 3570 fdput(f); 3571 return err; 3572 } 3573 3574 #define BPF_LINK_CREATE_LAST_FIELD link_create.flags 3575 static int link_create(union bpf_attr *attr) 3576 { 3577 enum bpf_prog_type ptype; 3578 struct bpf_prog *prog; 3579 int ret; 3580 3581 if (!capable(CAP_NET_ADMIN)) 3582 return -EPERM; 3583 3584 if (CHECK_ATTR(BPF_LINK_CREATE)) 3585 return -EINVAL; 3586 3587 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 3588 if (ptype == BPF_PROG_TYPE_UNSPEC) 3589 return -EINVAL; 3590 3591 prog = bpf_prog_get_type(attr->link_create.prog_fd, ptype); 3592 if (IS_ERR(prog)) 3593 return PTR_ERR(prog); 3594 3595 ret = bpf_prog_attach_check_attach_type(prog, 3596 attr->link_create.attach_type); 3597 if (ret) 3598 goto err_out; 3599 3600 switch (ptype) { 3601 case BPF_PROG_TYPE_CGROUP_SKB: 3602 case BPF_PROG_TYPE_CGROUP_SOCK: 3603 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3604 case BPF_PROG_TYPE_SOCK_OPS: 3605 case BPF_PROG_TYPE_CGROUP_DEVICE: 3606 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3607 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3608 ret = cgroup_bpf_link_attach(attr, prog); 3609 break; 3610 default: 3611 ret = -EINVAL; 3612 } 3613 3614 err_out: 3615 if (ret < 0) 3616 bpf_prog_put(prog); 3617 return ret; 3618 } 3619 3620 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 3621 3622 static int link_update(union bpf_attr *attr) 3623 { 3624 struct bpf_prog *old_prog = NULL, *new_prog; 3625 struct bpf_link *link; 3626 u32 flags; 3627 int ret; 3628 3629 if (!capable(CAP_NET_ADMIN)) 3630 return -EPERM; 3631 3632 if (CHECK_ATTR(BPF_LINK_UPDATE)) 3633 return -EINVAL; 3634 3635 flags = attr->link_update.flags; 3636 if (flags & ~BPF_F_REPLACE) 3637 return -EINVAL; 3638 3639 link = bpf_link_get_from_fd(attr->link_update.link_fd); 3640 if (IS_ERR(link)) 3641 return PTR_ERR(link); 3642 3643 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 3644 if (IS_ERR(new_prog)) { 3645 ret = PTR_ERR(new_prog); 3646 goto out_put_link; 3647 } 3648 3649 if (flags & BPF_F_REPLACE) { 3650 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 3651 if (IS_ERR(old_prog)) { 3652 ret = PTR_ERR(old_prog); 3653 old_prog = NULL; 3654 goto out_put_progs; 3655 } 3656 } else if (attr->link_update.old_prog_fd) { 3657 ret = -EINVAL; 3658 goto out_put_progs; 3659 } 3660 3661 #ifdef CONFIG_CGROUP_BPF 3662 if (link->ops == &bpf_cgroup_link_lops) { 3663 ret = cgroup_bpf_replace(link, old_prog, new_prog); 3664 goto out_put_progs; 3665 } 3666 #endif 3667 ret = -EINVAL; 3668 3669 out_put_progs: 3670 if (old_prog) 3671 bpf_prog_put(old_prog); 3672 if (ret) 3673 bpf_prog_put(new_prog); 3674 out_put_link: 3675 bpf_link_put(link); 3676 return ret; 3677 } 3678 3679 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 3680 { 3681 union bpf_attr attr; 3682 int err; 3683 3684 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 3685 return -EPERM; 3686 3687 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 3688 if (err) 3689 return err; 3690 size = min_t(u32, size, sizeof(attr)); 3691 3692 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 3693 memset(&attr, 0, sizeof(attr)); 3694 if (copy_from_user(&attr, uattr, size) != 0) 3695 return -EFAULT; 3696 3697 err = security_bpf(cmd, &attr, size); 3698 if (err < 0) 3699 return err; 3700 3701 switch (cmd) { 3702 case BPF_MAP_CREATE: 3703 err = map_create(&attr); 3704 break; 3705 case BPF_MAP_LOOKUP_ELEM: 3706 err = map_lookup_elem(&attr); 3707 break; 3708 case BPF_MAP_UPDATE_ELEM: 3709 err = map_update_elem(&attr); 3710 break; 3711 case BPF_MAP_DELETE_ELEM: 3712 err = map_delete_elem(&attr); 3713 break; 3714 case BPF_MAP_GET_NEXT_KEY: 3715 err = map_get_next_key(&attr); 3716 break; 3717 case BPF_MAP_FREEZE: 3718 err = map_freeze(&attr); 3719 break; 3720 case BPF_PROG_LOAD: 3721 err = bpf_prog_load(&attr, uattr); 3722 break; 3723 case BPF_OBJ_PIN: 3724 err = bpf_obj_pin(&attr); 3725 break; 3726 case BPF_OBJ_GET: 3727 err = bpf_obj_get(&attr); 3728 break; 3729 case BPF_PROG_ATTACH: 3730 err = bpf_prog_attach(&attr); 3731 break; 3732 case BPF_PROG_DETACH: 3733 err = bpf_prog_detach(&attr); 3734 break; 3735 case BPF_PROG_QUERY: 3736 err = bpf_prog_query(&attr, uattr); 3737 break; 3738 case BPF_PROG_TEST_RUN: 3739 err = bpf_prog_test_run(&attr, uattr); 3740 break; 3741 case BPF_PROG_GET_NEXT_ID: 3742 err = bpf_obj_get_next_id(&attr, uattr, 3743 &prog_idr, &prog_idr_lock); 3744 break; 3745 case BPF_MAP_GET_NEXT_ID: 3746 err = bpf_obj_get_next_id(&attr, uattr, 3747 &map_idr, &map_idr_lock); 3748 break; 3749 case BPF_BTF_GET_NEXT_ID: 3750 err = bpf_obj_get_next_id(&attr, uattr, 3751 &btf_idr, &btf_idr_lock); 3752 break; 3753 case BPF_PROG_GET_FD_BY_ID: 3754 err = bpf_prog_get_fd_by_id(&attr); 3755 break; 3756 case BPF_MAP_GET_FD_BY_ID: 3757 err = bpf_map_get_fd_by_id(&attr); 3758 break; 3759 case BPF_OBJ_GET_INFO_BY_FD: 3760 err = bpf_obj_get_info_by_fd(&attr, uattr); 3761 break; 3762 case BPF_RAW_TRACEPOINT_OPEN: 3763 err = bpf_raw_tracepoint_open(&attr); 3764 break; 3765 case BPF_BTF_LOAD: 3766 err = bpf_btf_load(&attr); 3767 break; 3768 case BPF_BTF_GET_FD_BY_ID: 3769 err = bpf_btf_get_fd_by_id(&attr); 3770 break; 3771 case BPF_TASK_FD_QUERY: 3772 err = bpf_task_fd_query(&attr, uattr); 3773 break; 3774 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 3775 err = map_lookup_and_delete_elem(&attr); 3776 break; 3777 case BPF_MAP_LOOKUP_BATCH: 3778 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_LOOKUP_BATCH); 3779 break; 3780 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 3781 err = bpf_map_do_batch(&attr, uattr, 3782 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 3783 break; 3784 case BPF_MAP_UPDATE_BATCH: 3785 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_UPDATE_BATCH); 3786 break; 3787 case BPF_MAP_DELETE_BATCH: 3788 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_DELETE_BATCH); 3789 break; 3790 case BPF_LINK_CREATE: 3791 err = link_create(&attr); 3792 break; 3793 case BPF_LINK_UPDATE: 3794 err = link_update(&attr); 3795 break; 3796 default: 3797 err = -EINVAL; 3798 break; 3799 } 3800 3801 return err; 3802 } 3803