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 29 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 30 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 31 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 32 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 33 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 34 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 35 IS_FD_HASH(map)) 36 37 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 38 39 DEFINE_PER_CPU(int, bpf_prog_active); 40 static DEFINE_IDR(prog_idr); 41 static DEFINE_SPINLOCK(prog_idr_lock); 42 static DEFINE_IDR(map_idr); 43 static DEFINE_SPINLOCK(map_idr_lock); 44 45 int sysctl_unprivileged_bpf_disabled __read_mostly; 46 47 static const struct bpf_map_ops * const bpf_map_types[] = { 48 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 49 #define BPF_MAP_TYPE(_id, _ops) \ 50 [_id] = &_ops, 51 #include <linux/bpf_types.h> 52 #undef BPF_PROG_TYPE 53 #undef BPF_MAP_TYPE 54 }; 55 56 /* 57 * If we're handed a bigger struct than we know of, ensure all the unknown bits 58 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 59 * we don't know about yet. 60 * 61 * There is a ToCToU between this function call and the following 62 * copy_from_user() call. However, this is not a concern since this function is 63 * meant to be a future-proofing of bits. 64 */ 65 int bpf_check_uarg_tail_zero(void __user *uaddr, 66 size_t expected_size, 67 size_t actual_size) 68 { 69 unsigned char __user *addr; 70 unsigned char __user *end; 71 unsigned char val; 72 int err; 73 74 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 75 return -E2BIG; 76 77 if (unlikely(!access_ok(uaddr, actual_size))) 78 return -EFAULT; 79 80 if (actual_size <= expected_size) 81 return 0; 82 83 addr = uaddr + expected_size; 84 end = uaddr + actual_size; 85 86 for (; addr < end; addr++) { 87 err = get_user(val, addr); 88 if (err) 89 return err; 90 if (val) 91 return -E2BIG; 92 } 93 94 return 0; 95 } 96 97 const struct bpf_map_ops bpf_map_offload_ops = { 98 .map_alloc = bpf_map_offload_map_alloc, 99 .map_free = bpf_map_offload_map_free, 100 .map_check_btf = map_check_no_btf, 101 }; 102 103 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 104 { 105 const struct bpf_map_ops *ops; 106 u32 type = attr->map_type; 107 struct bpf_map *map; 108 int err; 109 110 if (type >= ARRAY_SIZE(bpf_map_types)) 111 return ERR_PTR(-EINVAL); 112 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 113 ops = bpf_map_types[type]; 114 if (!ops) 115 return ERR_PTR(-EINVAL); 116 117 if (ops->map_alloc_check) { 118 err = ops->map_alloc_check(attr); 119 if (err) 120 return ERR_PTR(err); 121 } 122 if (attr->map_ifindex) 123 ops = &bpf_map_offload_ops; 124 map = ops->map_alloc(attr); 125 if (IS_ERR(map)) 126 return map; 127 map->ops = ops; 128 map->map_type = type; 129 return map; 130 } 131 132 static u32 bpf_map_value_size(struct bpf_map *map) 133 { 134 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 135 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 136 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 137 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 138 return round_up(map->value_size, 8) * num_possible_cpus(); 139 else if (IS_FD_MAP(map)) 140 return sizeof(u32); 141 else 142 return map->value_size; 143 } 144 145 static void maybe_wait_bpf_programs(struct bpf_map *map) 146 { 147 /* Wait for any running BPF programs to complete so that 148 * userspace, when we return to it, knows that all programs 149 * that could be running use the new map value. 150 */ 151 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 152 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 153 synchronize_rcu(); 154 } 155 156 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 157 void *value, __u64 flags) 158 { 159 int err; 160 161 /* Need to create a kthread, thus must support schedule */ 162 if (bpf_map_is_dev_bound(map)) { 163 return bpf_map_offload_update_elem(map, key, value, flags); 164 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 165 map->map_type == BPF_MAP_TYPE_SOCKHASH || 166 map->map_type == BPF_MAP_TYPE_SOCKMAP || 167 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 168 return map->ops->map_update_elem(map, key, value, flags); 169 } else if (IS_FD_PROG_ARRAY(map)) { 170 return bpf_fd_array_map_update_elem(map, f.file, key, value, 171 flags); 172 } 173 174 bpf_disable_instrumentation(); 175 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 176 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 177 err = bpf_percpu_hash_update(map, key, value, flags); 178 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 179 err = bpf_percpu_array_update(map, key, value, flags); 180 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 181 err = bpf_percpu_cgroup_storage_update(map, key, value, 182 flags); 183 } else if (IS_FD_ARRAY(map)) { 184 rcu_read_lock(); 185 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 186 flags); 187 rcu_read_unlock(); 188 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 189 rcu_read_lock(); 190 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 191 flags); 192 rcu_read_unlock(); 193 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 194 /* rcu_read_lock() is not needed */ 195 err = bpf_fd_reuseport_array_update_elem(map, key, value, 196 flags); 197 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 198 map->map_type == BPF_MAP_TYPE_STACK) { 199 err = map->ops->map_push_elem(map, value, flags); 200 } else { 201 rcu_read_lock(); 202 err = map->ops->map_update_elem(map, key, value, flags); 203 rcu_read_unlock(); 204 } 205 bpf_enable_instrumentation(); 206 maybe_wait_bpf_programs(map); 207 208 return err; 209 } 210 211 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 212 __u64 flags) 213 { 214 void *ptr; 215 int err; 216 217 if (bpf_map_is_dev_bound(map)) 218 return bpf_map_offload_lookup_elem(map, key, value); 219 220 bpf_disable_instrumentation(); 221 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 222 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 223 err = bpf_percpu_hash_copy(map, key, value); 224 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 225 err = bpf_percpu_array_copy(map, key, value); 226 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 227 err = bpf_percpu_cgroup_storage_copy(map, key, value); 228 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 229 err = bpf_stackmap_copy(map, key, value); 230 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 231 err = bpf_fd_array_map_lookup_elem(map, key, value); 232 } else if (IS_FD_HASH(map)) { 233 err = bpf_fd_htab_map_lookup_elem(map, key, value); 234 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 235 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 236 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 237 map->map_type == BPF_MAP_TYPE_STACK) { 238 err = map->ops->map_peek_elem(map, value); 239 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 240 /* struct_ops map requires directly updating "value" */ 241 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 242 } else { 243 rcu_read_lock(); 244 if (map->ops->map_lookup_elem_sys_only) 245 ptr = map->ops->map_lookup_elem_sys_only(map, key); 246 else 247 ptr = map->ops->map_lookup_elem(map, key); 248 if (IS_ERR(ptr)) { 249 err = PTR_ERR(ptr); 250 } else if (!ptr) { 251 err = -ENOENT; 252 } else { 253 err = 0; 254 if (flags & BPF_F_LOCK) 255 /* lock 'ptr' and copy everything but lock */ 256 copy_map_value_locked(map, value, ptr, true); 257 else 258 copy_map_value(map, value, ptr); 259 /* mask lock, since value wasn't zero inited */ 260 check_and_init_map_lock(map, value); 261 } 262 rcu_read_unlock(); 263 } 264 265 bpf_enable_instrumentation(); 266 maybe_wait_bpf_programs(map); 267 268 return err; 269 } 270 271 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 272 { 273 /* We really just want to fail instead of triggering OOM killer 274 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 275 * which is used for lower order allocation requests. 276 * 277 * It has been observed that higher order allocation requests done by 278 * vmalloc with __GFP_NORETRY being set might fail due to not trying 279 * to reclaim memory from the page cache, thus we set 280 * __GFP_RETRY_MAYFAIL to avoid such situations. 281 */ 282 283 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; 284 void *area; 285 286 if (size >= SIZE_MAX) 287 return NULL; 288 289 /* kmalloc()'ed memory can't be mmap()'ed */ 290 if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 291 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, 292 numa_node); 293 if (area != NULL) 294 return area; 295 } 296 if (mmapable) { 297 BUG_ON(!PAGE_ALIGNED(size)); 298 return vmalloc_user_node_flags(size, numa_node, GFP_KERNEL | 299 __GFP_RETRY_MAYFAIL | flags); 300 } 301 return __vmalloc_node_flags_caller(size, numa_node, 302 GFP_KERNEL | __GFP_RETRY_MAYFAIL | 303 flags, __builtin_return_address(0)); 304 } 305 306 void *bpf_map_area_alloc(u64 size, int numa_node) 307 { 308 return __bpf_map_area_alloc(size, numa_node, false); 309 } 310 311 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 312 { 313 return __bpf_map_area_alloc(size, numa_node, true); 314 } 315 316 void bpf_map_area_free(void *area) 317 { 318 kvfree(area); 319 } 320 321 static u32 bpf_map_flags_retain_permanent(u32 flags) 322 { 323 /* Some map creation flags are not tied to the map object but 324 * rather to the map fd instead, so they have no meaning upon 325 * map object inspection since multiple file descriptors with 326 * different (access) properties can exist here. Thus, given 327 * this has zero meaning for the map itself, lets clear these 328 * from here. 329 */ 330 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 331 } 332 333 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 334 { 335 map->map_type = attr->map_type; 336 map->key_size = attr->key_size; 337 map->value_size = attr->value_size; 338 map->max_entries = attr->max_entries; 339 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 340 map->numa_node = bpf_map_attr_numa_node(attr); 341 } 342 343 static int bpf_charge_memlock(struct user_struct *user, u32 pages) 344 { 345 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 346 347 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) { 348 atomic_long_sub(pages, &user->locked_vm); 349 return -EPERM; 350 } 351 return 0; 352 } 353 354 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages) 355 { 356 if (user) 357 atomic_long_sub(pages, &user->locked_vm); 358 } 359 360 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size) 361 { 362 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT; 363 struct user_struct *user; 364 int ret; 365 366 if (size >= U32_MAX - PAGE_SIZE) 367 return -E2BIG; 368 369 user = get_current_user(); 370 ret = bpf_charge_memlock(user, pages); 371 if (ret) { 372 free_uid(user); 373 return ret; 374 } 375 376 mem->pages = pages; 377 mem->user = user; 378 379 return 0; 380 } 381 382 void bpf_map_charge_finish(struct bpf_map_memory *mem) 383 { 384 bpf_uncharge_memlock(mem->user, mem->pages); 385 free_uid(mem->user); 386 } 387 388 void bpf_map_charge_move(struct bpf_map_memory *dst, 389 struct bpf_map_memory *src) 390 { 391 *dst = *src; 392 393 /* Make sure src will not be used for the redundant uncharging. */ 394 memset(src, 0, sizeof(struct bpf_map_memory)); 395 } 396 397 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages) 398 { 399 int ret; 400 401 ret = bpf_charge_memlock(map->memory.user, pages); 402 if (ret) 403 return ret; 404 map->memory.pages += pages; 405 return ret; 406 } 407 408 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages) 409 { 410 bpf_uncharge_memlock(map->memory.user, pages); 411 map->memory.pages -= pages; 412 } 413 414 static int bpf_map_alloc_id(struct bpf_map *map) 415 { 416 int id; 417 418 idr_preload(GFP_KERNEL); 419 spin_lock_bh(&map_idr_lock); 420 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 421 if (id > 0) 422 map->id = id; 423 spin_unlock_bh(&map_idr_lock); 424 idr_preload_end(); 425 426 if (WARN_ON_ONCE(!id)) 427 return -ENOSPC; 428 429 return id > 0 ? 0 : id; 430 } 431 432 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 433 { 434 unsigned long flags; 435 436 /* Offloaded maps are removed from the IDR store when their device 437 * disappears - even if someone holds an fd to them they are unusable, 438 * the memory is gone, all ops will fail; they are simply waiting for 439 * refcnt to drop to be freed. 440 */ 441 if (!map->id) 442 return; 443 444 if (do_idr_lock) 445 spin_lock_irqsave(&map_idr_lock, flags); 446 else 447 __acquire(&map_idr_lock); 448 449 idr_remove(&map_idr, map->id); 450 map->id = 0; 451 452 if (do_idr_lock) 453 spin_unlock_irqrestore(&map_idr_lock, flags); 454 else 455 __release(&map_idr_lock); 456 } 457 458 /* called from workqueue */ 459 static void bpf_map_free_deferred(struct work_struct *work) 460 { 461 struct bpf_map *map = container_of(work, struct bpf_map, work); 462 struct bpf_map_memory mem; 463 464 bpf_map_charge_move(&mem, &map->memory); 465 security_bpf_map_free(map); 466 /* implementation dependent freeing */ 467 map->ops->map_free(map); 468 bpf_map_charge_finish(&mem); 469 } 470 471 static void bpf_map_put_uref(struct bpf_map *map) 472 { 473 if (atomic64_dec_and_test(&map->usercnt)) { 474 if (map->ops->map_release_uref) 475 map->ops->map_release_uref(map); 476 } 477 } 478 479 /* decrement map refcnt and schedule it for freeing via workqueue 480 * (unrelying map implementation ops->map_free() might sleep) 481 */ 482 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 483 { 484 if (atomic64_dec_and_test(&map->refcnt)) { 485 /* bpf_map_free_id() must be called first */ 486 bpf_map_free_id(map, do_idr_lock); 487 btf_put(map->btf); 488 INIT_WORK(&map->work, bpf_map_free_deferred); 489 schedule_work(&map->work); 490 } 491 } 492 493 void bpf_map_put(struct bpf_map *map) 494 { 495 __bpf_map_put(map, true); 496 } 497 EXPORT_SYMBOL_GPL(bpf_map_put); 498 499 void bpf_map_put_with_uref(struct bpf_map *map) 500 { 501 bpf_map_put_uref(map); 502 bpf_map_put(map); 503 } 504 505 static int bpf_map_release(struct inode *inode, struct file *filp) 506 { 507 struct bpf_map *map = filp->private_data; 508 509 if (map->ops->map_release) 510 map->ops->map_release(map, filp); 511 512 bpf_map_put_with_uref(map); 513 return 0; 514 } 515 516 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 517 { 518 fmode_t mode = f.file->f_mode; 519 520 /* Our file permissions may have been overridden by global 521 * map permissions facing syscall side. 522 */ 523 if (READ_ONCE(map->frozen)) 524 mode &= ~FMODE_CAN_WRITE; 525 return mode; 526 } 527 528 #ifdef CONFIG_PROC_FS 529 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 530 { 531 const struct bpf_map *map = filp->private_data; 532 const struct bpf_array *array; 533 u32 type = 0, jited = 0; 534 535 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 536 array = container_of(map, struct bpf_array, map); 537 type = array->aux->type; 538 jited = array->aux->jited; 539 } 540 541 seq_printf(m, 542 "map_type:\t%u\n" 543 "key_size:\t%u\n" 544 "value_size:\t%u\n" 545 "max_entries:\t%u\n" 546 "map_flags:\t%#x\n" 547 "memlock:\t%llu\n" 548 "map_id:\t%u\n" 549 "frozen:\t%u\n", 550 map->map_type, 551 map->key_size, 552 map->value_size, 553 map->max_entries, 554 map->map_flags, 555 map->memory.pages * 1ULL << PAGE_SHIFT, 556 map->id, 557 READ_ONCE(map->frozen)); 558 if (type) { 559 seq_printf(m, "owner_prog_type:\t%u\n", type); 560 seq_printf(m, "owner_jited:\t%u\n", jited); 561 } 562 } 563 #endif 564 565 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 566 loff_t *ppos) 567 { 568 /* We need this handler such that alloc_file() enables 569 * f_mode with FMODE_CAN_READ. 570 */ 571 return -EINVAL; 572 } 573 574 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 575 size_t siz, loff_t *ppos) 576 { 577 /* We need this handler such that alloc_file() enables 578 * f_mode with FMODE_CAN_WRITE. 579 */ 580 return -EINVAL; 581 } 582 583 /* called for any extra memory-mapped regions (except initial) */ 584 static void bpf_map_mmap_open(struct vm_area_struct *vma) 585 { 586 struct bpf_map *map = vma->vm_file->private_data; 587 588 bpf_map_inc_with_uref(map); 589 590 if (vma->vm_flags & VM_WRITE) { 591 mutex_lock(&map->freeze_mutex); 592 map->writecnt++; 593 mutex_unlock(&map->freeze_mutex); 594 } 595 } 596 597 /* called for all unmapped memory region (including initial) */ 598 static void bpf_map_mmap_close(struct vm_area_struct *vma) 599 { 600 struct bpf_map *map = vma->vm_file->private_data; 601 602 if (vma->vm_flags & VM_WRITE) { 603 mutex_lock(&map->freeze_mutex); 604 map->writecnt--; 605 mutex_unlock(&map->freeze_mutex); 606 } 607 608 bpf_map_put_with_uref(map); 609 } 610 611 static const struct vm_operations_struct bpf_map_default_vmops = { 612 .open = bpf_map_mmap_open, 613 .close = bpf_map_mmap_close, 614 }; 615 616 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 617 { 618 struct bpf_map *map = filp->private_data; 619 int err; 620 621 if (!map->ops->map_mmap || map_value_has_spin_lock(map)) 622 return -ENOTSUPP; 623 624 if (!(vma->vm_flags & VM_SHARED)) 625 return -EINVAL; 626 627 mutex_lock(&map->freeze_mutex); 628 629 if ((vma->vm_flags & VM_WRITE) && map->frozen) { 630 err = -EPERM; 631 goto out; 632 } 633 634 /* set default open/close callbacks */ 635 vma->vm_ops = &bpf_map_default_vmops; 636 vma->vm_private_data = map; 637 638 err = map->ops->map_mmap(map, vma); 639 if (err) 640 goto out; 641 642 bpf_map_inc_with_uref(map); 643 644 if (vma->vm_flags & VM_WRITE) 645 map->writecnt++; 646 out: 647 mutex_unlock(&map->freeze_mutex); 648 return err; 649 } 650 651 const struct file_operations bpf_map_fops = { 652 #ifdef CONFIG_PROC_FS 653 .show_fdinfo = bpf_map_show_fdinfo, 654 #endif 655 .release = bpf_map_release, 656 .read = bpf_dummy_read, 657 .write = bpf_dummy_write, 658 .mmap = bpf_map_mmap, 659 }; 660 661 int bpf_map_new_fd(struct bpf_map *map, int flags) 662 { 663 int ret; 664 665 ret = security_bpf_map(map, OPEN_FMODE(flags)); 666 if (ret < 0) 667 return ret; 668 669 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 670 flags | O_CLOEXEC); 671 } 672 673 int bpf_get_file_flag(int flags) 674 { 675 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 676 return -EINVAL; 677 if (flags & BPF_F_RDONLY) 678 return O_RDONLY; 679 if (flags & BPF_F_WRONLY) 680 return O_WRONLY; 681 return O_RDWR; 682 } 683 684 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 685 #define CHECK_ATTR(CMD) \ 686 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 687 sizeof(attr->CMD##_LAST_FIELD), 0, \ 688 sizeof(*attr) - \ 689 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 690 sizeof(attr->CMD##_LAST_FIELD)) != NULL 691 692 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes. 693 * Return 0 on success and < 0 on error. 694 */ 695 static int bpf_obj_name_cpy(char *dst, const char *src) 696 { 697 const char *end = src + BPF_OBJ_NAME_LEN; 698 699 memset(dst, 0, BPF_OBJ_NAME_LEN); 700 /* Copy all isalnum(), '_' and '.' chars. */ 701 while (src < end && *src) { 702 if (!isalnum(*src) && 703 *src != '_' && *src != '.') 704 return -EINVAL; 705 *dst++ = *src++; 706 } 707 708 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */ 709 if (src == end) 710 return -EINVAL; 711 712 return 0; 713 } 714 715 int map_check_no_btf(const struct bpf_map *map, 716 const struct btf *btf, 717 const struct btf_type *key_type, 718 const struct btf_type *value_type) 719 { 720 return -ENOTSUPP; 721 } 722 723 static int map_check_btf(struct bpf_map *map, const struct btf *btf, 724 u32 btf_key_id, u32 btf_value_id) 725 { 726 const struct btf_type *key_type, *value_type; 727 u32 key_size, value_size; 728 int ret = 0; 729 730 /* Some maps allow key to be unspecified. */ 731 if (btf_key_id) { 732 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 733 if (!key_type || key_size != map->key_size) 734 return -EINVAL; 735 } else { 736 key_type = btf_type_by_id(btf, 0); 737 if (!map->ops->map_check_btf) 738 return -EINVAL; 739 } 740 741 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 742 if (!value_type || value_size != map->value_size) 743 return -EINVAL; 744 745 map->spin_lock_off = btf_find_spin_lock(btf, value_type); 746 747 if (map_value_has_spin_lock(map)) { 748 if (map->map_flags & BPF_F_RDONLY_PROG) 749 return -EACCES; 750 if (map->map_type != BPF_MAP_TYPE_HASH && 751 map->map_type != BPF_MAP_TYPE_ARRAY && 752 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 753 map->map_type != BPF_MAP_TYPE_SK_STORAGE) 754 return -ENOTSUPP; 755 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > 756 map->value_size) { 757 WARN_ONCE(1, 758 "verifier bug spin_lock_off %d value_size %d\n", 759 map->spin_lock_off, map->value_size); 760 return -EFAULT; 761 } 762 } 763 764 if (map->ops->map_check_btf) 765 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 766 767 return ret; 768 } 769 770 #define BPF_MAP_CREATE_LAST_FIELD btf_vmlinux_value_type_id 771 /* called via syscall */ 772 static int map_create(union bpf_attr *attr) 773 { 774 int numa_node = bpf_map_attr_numa_node(attr); 775 struct bpf_map_memory mem; 776 struct bpf_map *map; 777 int f_flags; 778 int err; 779 780 err = CHECK_ATTR(BPF_MAP_CREATE); 781 if (err) 782 return -EINVAL; 783 784 if (attr->btf_vmlinux_value_type_id) { 785 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 786 attr->btf_key_type_id || attr->btf_value_type_id) 787 return -EINVAL; 788 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 789 return -EINVAL; 790 } 791 792 f_flags = bpf_get_file_flag(attr->map_flags); 793 if (f_flags < 0) 794 return f_flags; 795 796 if (numa_node != NUMA_NO_NODE && 797 ((unsigned int)numa_node >= nr_node_ids || 798 !node_online(numa_node))) 799 return -EINVAL; 800 801 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 802 map = find_and_alloc_map(attr); 803 if (IS_ERR(map)) 804 return PTR_ERR(map); 805 806 err = bpf_obj_name_cpy(map->name, attr->map_name); 807 if (err) 808 goto free_map; 809 810 atomic64_set(&map->refcnt, 1); 811 atomic64_set(&map->usercnt, 1); 812 mutex_init(&map->freeze_mutex); 813 814 map->spin_lock_off = -EINVAL; 815 if (attr->btf_key_type_id || attr->btf_value_type_id || 816 /* Even the map's value is a kernel's struct, 817 * the bpf_prog.o must have BTF to begin with 818 * to figure out the corresponding kernel's 819 * counter part. Thus, attr->btf_fd has 820 * to be valid also. 821 */ 822 attr->btf_vmlinux_value_type_id) { 823 struct btf *btf; 824 825 btf = btf_get_by_fd(attr->btf_fd); 826 if (IS_ERR(btf)) { 827 err = PTR_ERR(btf); 828 goto free_map; 829 } 830 map->btf = btf; 831 832 if (attr->btf_value_type_id) { 833 err = map_check_btf(map, btf, attr->btf_key_type_id, 834 attr->btf_value_type_id); 835 if (err) 836 goto free_map; 837 } 838 839 map->btf_key_type_id = attr->btf_key_type_id; 840 map->btf_value_type_id = attr->btf_value_type_id; 841 map->btf_vmlinux_value_type_id = 842 attr->btf_vmlinux_value_type_id; 843 } 844 845 err = security_bpf_map_alloc(map); 846 if (err) 847 goto free_map; 848 849 err = bpf_map_alloc_id(map); 850 if (err) 851 goto free_map_sec; 852 853 err = bpf_map_new_fd(map, f_flags); 854 if (err < 0) { 855 /* failed to allocate fd. 856 * bpf_map_put_with_uref() is needed because the above 857 * bpf_map_alloc_id() has published the map 858 * to the userspace and the userspace may 859 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 860 */ 861 bpf_map_put_with_uref(map); 862 return err; 863 } 864 865 return err; 866 867 free_map_sec: 868 security_bpf_map_free(map); 869 free_map: 870 btf_put(map->btf); 871 bpf_map_charge_move(&mem, &map->memory); 872 map->ops->map_free(map); 873 bpf_map_charge_finish(&mem); 874 return err; 875 } 876 877 /* if error is returned, fd is released. 878 * On success caller should complete fd access with matching fdput() 879 */ 880 struct bpf_map *__bpf_map_get(struct fd f) 881 { 882 if (!f.file) 883 return ERR_PTR(-EBADF); 884 if (f.file->f_op != &bpf_map_fops) { 885 fdput(f); 886 return ERR_PTR(-EINVAL); 887 } 888 889 return f.file->private_data; 890 } 891 892 void bpf_map_inc(struct bpf_map *map) 893 { 894 atomic64_inc(&map->refcnt); 895 } 896 EXPORT_SYMBOL_GPL(bpf_map_inc); 897 898 void bpf_map_inc_with_uref(struct bpf_map *map) 899 { 900 atomic64_inc(&map->refcnt); 901 atomic64_inc(&map->usercnt); 902 } 903 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 904 905 struct bpf_map *bpf_map_get(u32 ufd) 906 { 907 struct fd f = fdget(ufd); 908 struct bpf_map *map; 909 910 map = __bpf_map_get(f); 911 if (IS_ERR(map)) 912 return map; 913 914 bpf_map_inc(map); 915 fdput(f); 916 917 return map; 918 } 919 920 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 921 { 922 struct fd f = fdget(ufd); 923 struct bpf_map *map; 924 925 map = __bpf_map_get(f); 926 if (IS_ERR(map)) 927 return map; 928 929 bpf_map_inc_with_uref(map); 930 fdput(f); 931 932 return map; 933 } 934 935 /* map_idr_lock should have been held */ 936 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 937 { 938 int refold; 939 940 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 941 if (!refold) 942 return ERR_PTR(-ENOENT); 943 if (uref) 944 atomic64_inc(&map->usercnt); 945 946 return map; 947 } 948 949 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 950 { 951 spin_lock_bh(&map_idr_lock); 952 map = __bpf_map_inc_not_zero(map, false); 953 spin_unlock_bh(&map_idr_lock); 954 955 return map; 956 } 957 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 958 959 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 960 { 961 return -ENOTSUPP; 962 } 963 964 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 965 { 966 if (key_size) 967 return memdup_user(ukey, key_size); 968 969 if (ukey) 970 return ERR_PTR(-EINVAL); 971 972 return NULL; 973 } 974 975 /* last field in 'union bpf_attr' used by this command */ 976 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 977 978 static int map_lookup_elem(union bpf_attr *attr) 979 { 980 void __user *ukey = u64_to_user_ptr(attr->key); 981 void __user *uvalue = u64_to_user_ptr(attr->value); 982 int ufd = attr->map_fd; 983 struct bpf_map *map; 984 void *key, *value; 985 u32 value_size; 986 struct fd f; 987 int err; 988 989 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 990 return -EINVAL; 991 992 if (attr->flags & ~BPF_F_LOCK) 993 return -EINVAL; 994 995 f = fdget(ufd); 996 map = __bpf_map_get(f); 997 if (IS_ERR(map)) 998 return PTR_ERR(map); 999 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1000 err = -EPERM; 1001 goto err_put; 1002 } 1003 1004 if ((attr->flags & BPF_F_LOCK) && 1005 !map_value_has_spin_lock(map)) { 1006 err = -EINVAL; 1007 goto err_put; 1008 } 1009 1010 key = __bpf_copy_key(ukey, map->key_size); 1011 if (IS_ERR(key)) { 1012 err = PTR_ERR(key); 1013 goto err_put; 1014 } 1015 1016 value_size = bpf_map_value_size(map); 1017 1018 err = -ENOMEM; 1019 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1020 if (!value) 1021 goto free_key; 1022 1023 err = bpf_map_copy_value(map, key, value, attr->flags); 1024 if (err) 1025 goto free_value; 1026 1027 err = -EFAULT; 1028 if (copy_to_user(uvalue, value, value_size) != 0) 1029 goto free_value; 1030 1031 err = 0; 1032 1033 free_value: 1034 kfree(value); 1035 free_key: 1036 kfree(key); 1037 err_put: 1038 fdput(f); 1039 return err; 1040 } 1041 1042 1043 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1044 1045 static int map_update_elem(union bpf_attr *attr) 1046 { 1047 void __user *ukey = u64_to_user_ptr(attr->key); 1048 void __user *uvalue = u64_to_user_ptr(attr->value); 1049 int ufd = attr->map_fd; 1050 struct bpf_map *map; 1051 void *key, *value; 1052 u32 value_size; 1053 struct fd f; 1054 int err; 1055 1056 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1057 return -EINVAL; 1058 1059 f = fdget(ufd); 1060 map = __bpf_map_get(f); 1061 if (IS_ERR(map)) 1062 return PTR_ERR(map); 1063 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1064 err = -EPERM; 1065 goto err_put; 1066 } 1067 1068 if ((attr->flags & BPF_F_LOCK) && 1069 !map_value_has_spin_lock(map)) { 1070 err = -EINVAL; 1071 goto err_put; 1072 } 1073 1074 key = __bpf_copy_key(ukey, map->key_size); 1075 if (IS_ERR(key)) { 1076 err = PTR_ERR(key); 1077 goto err_put; 1078 } 1079 1080 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1081 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 1082 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 1083 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 1084 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 1085 else 1086 value_size = map->value_size; 1087 1088 err = -ENOMEM; 1089 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1090 if (!value) 1091 goto free_key; 1092 1093 err = -EFAULT; 1094 if (copy_from_user(value, uvalue, value_size) != 0) 1095 goto free_value; 1096 1097 err = bpf_map_update_value(map, f, key, value, attr->flags); 1098 1099 free_value: 1100 kfree(value); 1101 free_key: 1102 kfree(key); 1103 err_put: 1104 fdput(f); 1105 return err; 1106 } 1107 1108 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1109 1110 static int map_delete_elem(union bpf_attr *attr) 1111 { 1112 void __user *ukey = u64_to_user_ptr(attr->key); 1113 int ufd = attr->map_fd; 1114 struct bpf_map *map; 1115 struct fd f; 1116 void *key; 1117 int err; 1118 1119 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1120 return -EINVAL; 1121 1122 f = fdget(ufd); 1123 map = __bpf_map_get(f); 1124 if (IS_ERR(map)) 1125 return PTR_ERR(map); 1126 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1127 err = -EPERM; 1128 goto err_put; 1129 } 1130 1131 key = __bpf_copy_key(ukey, map->key_size); 1132 if (IS_ERR(key)) { 1133 err = PTR_ERR(key); 1134 goto err_put; 1135 } 1136 1137 if (bpf_map_is_dev_bound(map)) { 1138 err = bpf_map_offload_delete_elem(map, key); 1139 goto out; 1140 } else if (IS_FD_PROG_ARRAY(map) || 1141 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1142 /* These maps require sleepable context */ 1143 err = map->ops->map_delete_elem(map, key); 1144 goto out; 1145 } 1146 1147 bpf_disable_instrumentation(); 1148 rcu_read_lock(); 1149 err = map->ops->map_delete_elem(map, key); 1150 rcu_read_unlock(); 1151 bpf_enable_instrumentation(); 1152 maybe_wait_bpf_programs(map); 1153 out: 1154 kfree(key); 1155 err_put: 1156 fdput(f); 1157 return err; 1158 } 1159 1160 /* last field in 'union bpf_attr' used by this command */ 1161 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1162 1163 static int map_get_next_key(union bpf_attr *attr) 1164 { 1165 void __user *ukey = u64_to_user_ptr(attr->key); 1166 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1167 int ufd = attr->map_fd; 1168 struct bpf_map *map; 1169 void *key, *next_key; 1170 struct fd f; 1171 int err; 1172 1173 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1174 return -EINVAL; 1175 1176 f = fdget(ufd); 1177 map = __bpf_map_get(f); 1178 if (IS_ERR(map)) 1179 return PTR_ERR(map); 1180 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1181 err = -EPERM; 1182 goto err_put; 1183 } 1184 1185 if (ukey) { 1186 key = __bpf_copy_key(ukey, map->key_size); 1187 if (IS_ERR(key)) { 1188 err = PTR_ERR(key); 1189 goto err_put; 1190 } 1191 } else { 1192 key = NULL; 1193 } 1194 1195 err = -ENOMEM; 1196 next_key = kmalloc(map->key_size, GFP_USER); 1197 if (!next_key) 1198 goto free_key; 1199 1200 if (bpf_map_is_dev_bound(map)) { 1201 err = bpf_map_offload_get_next_key(map, key, next_key); 1202 goto out; 1203 } 1204 1205 rcu_read_lock(); 1206 err = map->ops->map_get_next_key(map, key, next_key); 1207 rcu_read_unlock(); 1208 out: 1209 if (err) 1210 goto free_next_key; 1211 1212 err = -EFAULT; 1213 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1214 goto free_next_key; 1215 1216 err = 0; 1217 1218 free_next_key: 1219 kfree(next_key); 1220 free_key: 1221 kfree(key); 1222 err_put: 1223 fdput(f); 1224 return err; 1225 } 1226 1227 int generic_map_delete_batch(struct bpf_map *map, 1228 const union bpf_attr *attr, 1229 union bpf_attr __user *uattr) 1230 { 1231 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1232 u32 cp, max_count; 1233 int err = 0; 1234 void *key; 1235 1236 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1237 return -EINVAL; 1238 1239 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1240 !map_value_has_spin_lock(map)) { 1241 return -EINVAL; 1242 } 1243 1244 max_count = attr->batch.count; 1245 if (!max_count) 1246 return 0; 1247 1248 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1249 if (!key) 1250 return -ENOMEM; 1251 1252 for (cp = 0; cp < max_count; cp++) { 1253 err = -EFAULT; 1254 if (copy_from_user(key, keys + cp * map->key_size, 1255 map->key_size)) 1256 break; 1257 1258 if (bpf_map_is_dev_bound(map)) { 1259 err = bpf_map_offload_delete_elem(map, key); 1260 break; 1261 } 1262 1263 bpf_disable_instrumentation(); 1264 rcu_read_lock(); 1265 err = map->ops->map_delete_elem(map, key); 1266 rcu_read_unlock(); 1267 bpf_enable_instrumentation(); 1268 maybe_wait_bpf_programs(map); 1269 if (err) 1270 break; 1271 } 1272 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1273 err = -EFAULT; 1274 1275 kfree(key); 1276 return err; 1277 } 1278 1279 int generic_map_update_batch(struct bpf_map *map, 1280 const union bpf_attr *attr, 1281 union bpf_attr __user *uattr) 1282 { 1283 void __user *values = u64_to_user_ptr(attr->batch.values); 1284 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1285 u32 value_size, cp, max_count; 1286 int ufd = attr->map_fd; 1287 void *key, *value; 1288 struct fd f; 1289 int err = 0; 1290 1291 f = fdget(ufd); 1292 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1293 return -EINVAL; 1294 1295 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1296 !map_value_has_spin_lock(map)) { 1297 return -EINVAL; 1298 } 1299 1300 value_size = bpf_map_value_size(map); 1301 1302 max_count = attr->batch.count; 1303 if (!max_count) 1304 return 0; 1305 1306 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1307 if (!key) 1308 return -ENOMEM; 1309 1310 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1311 if (!value) { 1312 kfree(key); 1313 return -ENOMEM; 1314 } 1315 1316 for (cp = 0; cp < max_count; cp++) { 1317 err = -EFAULT; 1318 if (copy_from_user(key, keys + cp * map->key_size, 1319 map->key_size) || 1320 copy_from_user(value, values + cp * value_size, value_size)) 1321 break; 1322 1323 err = bpf_map_update_value(map, f, key, value, 1324 attr->batch.elem_flags); 1325 1326 if (err) 1327 break; 1328 } 1329 1330 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1331 err = -EFAULT; 1332 1333 kfree(value); 1334 kfree(key); 1335 return err; 1336 } 1337 1338 #define MAP_LOOKUP_RETRIES 3 1339 1340 int generic_map_lookup_batch(struct bpf_map *map, 1341 const union bpf_attr *attr, 1342 union bpf_attr __user *uattr) 1343 { 1344 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1345 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1346 void __user *values = u64_to_user_ptr(attr->batch.values); 1347 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1348 void *buf, *buf_prevkey, *prev_key, *key, *value; 1349 int err, retry = MAP_LOOKUP_RETRIES; 1350 u32 value_size, cp, max_count; 1351 1352 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1353 return -EINVAL; 1354 1355 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1356 !map_value_has_spin_lock(map)) 1357 return -EINVAL; 1358 1359 value_size = bpf_map_value_size(map); 1360 1361 max_count = attr->batch.count; 1362 if (!max_count) 1363 return 0; 1364 1365 if (put_user(0, &uattr->batch.count)) 1366 return -EFAULT; 1367 1368 buf_prevkey = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1369 if (!buf_prevkey) 1370 return -ENOMEM; 1371 1372 buf = kmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1373 if (!buf) { 1374 kvfree(buf_prevkey); 1375 return -ENOMEM; 1376 } 1377 1378 err = -EFAULT; 1379 prev_key = NULL; 1380 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1381 goto free_buf; 1382 key = buf; 1383 value = key + map->key_size; 1384 if (ubatch) 1385 prev_key = buf_prevkey; 1386 1387 for (cp = 0; cp < max_count;) { 1388 rcu_read_lock(); 1389 err = map->ops->map_get_next_key(map, prev_key, key); 1390 rcu_read_unlock(); 1391 if (err) 1392 break; 1393 err = bpf_map_copy_value(map, key, value, 1394 attr->batch.elem_flags); 1395 1396 if (err == -ENOENT) { 1397 if (retry) { 1398 retry--; 1399 continue; 1400 } 1401 err = -EINTR; 1402 break; 1403 } 1404 1405 if (err) 1406 goto free_buf; 1407 1408 if (copy_to_user(keys + cp * map->key_size, key, 1409 map->key_size)) { 1410 err = -EFAULT; 1411 goto free_buf; 1412 } 1413 if (copy_to_user(values + cp * value_size, value, value_size)) { 1414 err = -EFAULT; 1415 goto free_buf; 1416 } 1417 1418 if (!prev_key) 1419 prev_key = buf_prevkey; 1420 1421 swap(prev_key, key); 1422 retry = MAP_LOOKUP_RETRIES; 1423 cp++; 1424 } 1425 1426 if (err == -EFAULT) 1427 goto free_buf; 1428 1429 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1430 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1431 err = -EFAULT; 1432 1433 free_buf: 1434 kfree(buf_prevkey); 1435 kfree(buf); 1436 return err; 1437 } 1438 1439 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value 1440 1441 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1442 { 1443 void __user *ukey = u64_to_user_ptr(attr->key); 1444 void __user *uvalue = u64_to_user_ptr(attr->value); 1445 int ufd = attr->map_fd; 1446 struct bpf_map *map; 1447 void *key, *value; 1448 u32 value_size; 1449 struct fd f; 1450 int err; 1451 1452 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1453 return -EINVAL; 1454 1455 f = fdget(ufd); 1456 map = __bpf_map_get(f); 1457 if (IS_ERR(map)) 1458 return PTR_ERR(map); 1459 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1460 err = -EPERM; 1461 goto err_put; 1462 } 1463 1464 key = __bpf_copy_key(ukey, map->key_size); 1465 if (IS_ERR(key)) { 1466 err = PTR_ERR(key); 1467 goto err_put; 1468 } 1469 1470 value_size = map->value_size; 1471 1472 err = -ENOMEM; 1473 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1474 if (!value) 1475 goto free_key; 1476 1477 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1478 map->map_type == BPF_MAP_TYPE_STACK) { 1479 err = map->ops->map_pop_elem(map, value); 1480 } else { 1481 err = -ENOTSUPP; 1482 } 1483 1484 if (err) 1485 goto free_value; 1486 1487 if (copy_to_user(uvalue, value, value_size) != 0) 1488 goto free_value; 1489 1490 err = 0; 1491 1492 free_value: 1493 kfree(value); 1494 free_key: 1495 kfree(key); 1496 err_put: 1497 fdput(f); 1498 return err; 1499 } 1500 1501 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1502 1503 static int map_freeze(const union bpf_attr *attr) 1504 { 1505 int err = 0, ufd = attr->map_fd; 1506 struct bpf_map *map; 1507 struct fd f; 1508 1509 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1510 return -EINVAL; 1511 1512 f = fdget(ufd); 1513 map = __bpf_map_get(f); 1514 if (IS_ERR(map)) 1515 return PTR_ERR(map); 1516 1517 mutex_lock(&map->freeze_mutex); 1518 1519 if (map->writecnt) { 1520 err = -EBUSY; 1521 goto err_put; 1522 } 1523 if (READ_ONCE(map->frozen)) { 1524 err = -EBUSY; 1525 goto err_put; 1526 } 1527 if (!capable(CAP_SYS_ADMIN)) { 1528 err = -EPERM; 1529 goto err_put; 1530 } 1531 1532 WRITE_ONCE(map->frozen, true); 1533 err_put: 1534 mutex_unlock(&map->freeze_mutex); 1535 fdput(f); 1536 return err; 1537 } 1538 1539 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1540 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1541 [_id] = & _name ## _prog_ops, 1542 #define BPF_MAP_TYPE(_id, _ops) 1543 #include <linux/bpf_types.h> 1544 #undef BPF_PROG_TYPE 1545 #undef BPF_MAP_TYPE 1546 }; 1547 1548 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1549 { 1550 const struct bpf_prog_ops *ops; 1551 1552 if (type >= ARRAY_SIZE(bpf_prog_types)) 1553 return -EINVAL; 1554 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1555 ops = bpf_prog_types[type]; 1556 if (!ops) 1557 return -EINVAL; 1558 1559 if (!bpf_prog_is_dev_bound(prog->aux)) 1560 prog->aux->ops = ops; 1561 else 1562 prog->aux->ops = &bpf_offload_prog_ops; 1563 prog->type = type; 1564 return 0; 1565 } 1566 1567 enum bpf_audit { 1568 BPF_AUDIT_LOAD, 1569 BPF_AUDIT_UNLOAD, 1570 BPF_AUDIT_MAX, 1571 }; 1572 1573 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1574 [BPF_AUDIT_LOAD] = "LOAD", 1575 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1576 }; 1577 1578 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1579 { 1580 struct audit_context *ctx = NULL; 1581 struct audit_buffer *ab; 1582 1583 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1584 return; 1585 if (audit_enabled == AUDIT_OFF) 1586 return; 1587 if (op == BPF_AUDIT_LOAD) 1588 ctx = audit_context(); 1589 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1590 if (unlikely(!ab)) 1591 return; 1592 audit_log_format(ab, "prog-id=%u op=%s", 1593 prog->aux->id, bpf_audit_str[op]); 1594 audit_log_end(ab); 1595 } 1596 1597 int __bpf_prog_charge(struct user_struct *user, u32 pages) 1598 { 1599 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 1600 unsigned long user_bufs; 1601 1602 if (user) { 1603 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 1604 if (user_bufs > memlock_limit) { 1605 atomic_long_sub(pages, &user->locked_vm); 1606 return -EPERM; 1607 } 1608 } 1609 1610 return 0; 1611 } 1612 1613 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 1614 { 1615 if (user) 1616 atomic_long_sub(pages, &user->locked_vm); 1617 } 1618 1619 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 1620 { 1621 struct user_struct *user = get_current_user(); 1622 int ret; 1623 1624 ret = __bpf_prog_charge(user, prog->pages); 1625 if (ret) { 1626 free_uid(user); 1627 return ret; 1628 } 1629 1630 prog->aux->user = user; 1631 return 0; 1632 } 1633 1634 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 1635 { 1636 struct user_struct *user = prog->aux->user; 1637 1638 __bpf_prog_uncharge(user, prog->pages); 1639 free_uid(user); 1640 } 1641 1642 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1643 { 1644 int id; 1645 1646 idr_preload(GFP_KERNEL); 1647 spin_lock_bh(&prog_idr_lock); 1648 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1649 if (id > 0) 1650 prog->aux->id = id; 1651 spin_unlock_bh(&prog_idr_lock); 1652 idr_preload_end(); 1653 1654 /* id is in [1, INT_MAX) */ 1655 if (WARN_ON_ONCE(!id)) 1656 return -ENOSPC; 1657 1658 return id > 0 ? 0 : id; 1659 } 1660 1661 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1662 { 1663 /* cBPF to eBPF migrations are currently not in the idr store. 1664 * Offloaded programs are removed from the store when their device 1665 * disappears - even if someone grabs an fd to them they are unusable, 1666 * simply waiting for refcnt to drop to be freed. 1667 */ 1668 if (!prog->aux->id) 1669 return; 1670 1671 if (do_idr_lock) 1672 spin_lock_bh(&prog_idr_lock); 1673 else 1674 __acquire(&prog_idr_lock); 1675 1676 idr_remove(&prog_idr, prog->aux->id); 1677 prog->aux->id = 0; 1678 1679 if (do_idr_lock) 1680 spin_unlock_bh(&prog_idr_lock); 1681 else 1682 __release(&prog_idr_lock); 1683 } 1684 1685 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1686 { 1687 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1688 1689 kvfree(aux->func_info); 1690 kfree(aux->func_info_aux); 1691 bpf_prog_uncharge_memlock(aux->prog); 1692 security_bpf_prog_free(aux); 1693 bpf_prog_free(aux->prog); 1694 } 1695 1696 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1697 { 1698 bpf_prog_kallsyms_del_all(prog); 1699 btf_put(prog->aux->btf); 1700 bpf_prog_free_linfo(prog); 1701 1702 if (deferred) 1703 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1704 else 1705 __bpf_prog_put_rcu(&prog->aux->rcu); 1706 } 1707 1708 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1709 { 1710 if (atomic64_dec_and_test(&prog->aux->refcnt)) { 1711 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1712 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1713 /* bpf_prog_free_id() must be called first */ 1714 bpf_prog_free_id(prog, do_idr_lock); 1715 __bpf_prog_put_noref(prog, true); 1716 } 1717 } 1718 1719 void bpf_prog_put(struct bpf_prog *prog) 1720 { 1721 __bpf_prog_put(prog, true); 1722 } 1723 EXPORT_SYMBOL_GPL(bpf_prog_put); 1724 1725 static int bpf_prog_release(struct inode *inode, struct file *filp) 1726 { 1727 struct bpf_prog *prog = filp->private_data; 1728 1729 bpf_prog_put(prog); 1730 return 0; 1731 } 1732 1733 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1734 struct bpf_prog_stats *stats) 1735 { 1736 u64 nsecs = 0, cnt = 0; 1737 int cpu; 1738 1739 for_each_possible_cpu(cpu) { 1740 const struct bpf_prog_stats *st; 1741 unsigned int start; 1742 u64 tnsecs, tcnt; 1743 1744 st = per_cpu_ptr(prog->aux->stats, cpu); 1745 do { 1746 start = u64_stats_fetch_begin_irq(&st->syncp); 1747 tnsecs = st->nsecs; 1748 tcnt = st->cnt; 1749 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1750 nsecs += tnsecs; 1751 cnt += tcnt; 1752 } 1753 stats->nsecs = nsecs; 1754 stats->cnt = cnt; 1755 } 1756 1757 #ifdef CONFIG_PROC_FS 1758 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1759 { 1760 const struct bpf_prog *prog = filp->private_data; 1761 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1762 struct bpf_prog_stats stats; 1763 1764 bpf_prog_get_stats(prog, &stats); 1765 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1766 seq_printf(m, 1767 "prog_type:\t%u\n" 1768 "prog_jited:\t%u\n" 1769 "prog_tag:\t%s\n" 1770 "memlock:\t%llu\n" 1771 "prog_id:\t%u\n" 1772 "run_time_ns:\t%llu\n" 1773 "run_cnt:\t%llu\n", 1774 prog->type, 1775 prog->jited, 1776 prog_tag, 1777 prog->pages * 1ULL << PAGE_SHIFT, 1778 prog->aux->id, 1779 stats.nsecs, 1780 stats.cnt); 1781 } 1782 #endif 1783 1784 const struct file_operations bpf_prog_fops = { 1785 #ifdef CONFIG_PROC_FS 1786 .show_fdinfo = bpf_prog_show_fdinfo, 1787 #endif 1788 .release = bpf_prog_release, 1789 .read = bpf_dummy_read, 1790 .write = bpf_dummy_write, 1791 }; 1792 1793 int bpf_prog_new_fd(struct bpf_prog *prog) 1794 { 1795 int ret; 1796 1797 ret = security_bpf_prog(prog); 1798 if (ret < 0) 1799 return ret; 1800 1801 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1802 O_RDWR | O_CLOEXEC); 1803 } 1804 1805 static struct bpf_prog *____bpf_prog_get(struct fd f) 1806 { 1807 if (!f.file) 1808 return ERR_PTR(-EBADF); 1809 if (f.file->f_op != &bpf_prog_fops) { 1810 fdput(f); 1811 return ERR_PTR(-EINVAL); 1812 } 1813 1814 return f.file->private_data; 1815 } 1816 1817 void bpf_prog_add(struct bpf_prog *prog, int i) 1818 { 1819 atomic64_add(i, &prog->aux->refcnt); 1820 } 1821 EXPORT_SYMBOL_GPL(bpf_prog_add); 1822 1823 void bpf_prog_sub(struct bpf_prog *prog, int i) 1824 { 1825 /* Only to be used for undoing previous bpf_prog_add() in some 1826 * error path. We still know that another entity in our call 1827 * path holds a reference to the program, thus atomic_sub() can 1828 * be safely used in such cases! 1829 */ 1830 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1831 } 1832 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1833 1834 void bpf_prog_inc(struct bpf_prog *prog) 1835 { 1836 atomic64_inc(&prog->aux->refcnt); 1837 } 1838 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1839 1840 /* prog_idr_lock should have been held */ 1841 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1842 { 1843 int refold; 1844 1845 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1846 1847 if (!refold) 1848 return ERR_PTR(-ENOENT); 1849 1850 return prog; 1851 } 1852 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1853 1854 bool bpf_prog_get_ok(struct bpf_prog *prog, 1855 enum bpf_prog_type *attach_type, bool attach_drv) 1856 { 1857 /* not an attachment, just a refcount inc, always allow */ 1858 if (!attach_type) 1859 return true; 1860 1861 if (prog->type != *attach_type) 1862 return false; 1863 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1864 return false; 1865 1866 return true; 1867 } 1868 1869 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1870 bool attach_drv) 1871 { 1872 struct fd f = fdget(ufd); 1873 struct bpf_prog *prog; 1874 1875 prog = ____bpf_prog_get(f); 1876 if (IS_ERR(prog)) 1877 return prog; 1878 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1879 prog = ERR_PTR(-EINVAL); 1880 goto out; 1881 } 1882 1883 bpf_prog_inc(prog); 1884 out: 1885 fdput(f); 1886 return prog; 1887 } 1888 1889 struct bpf_prog *bpf_prog_get(u32 ufd) 1890 { 1891 return __bpf_prog_get(ufd, NULL, false); 1892 } 1893 1894 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1895 bool attach_drv) 1896 { 1897 return __bpf_prog_get(ufd, &type, attach_drv); 1898 } 1899 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1900 1901 /* Initially all BPF programs could be loaded w/o specifying 1902 * expected_attach_type. Later for some of them specifying expected_attach_type 1903 * at load time became required so that program could be validated properly. 1904 * Programs of types that are allowed to be loaded both w/ and w/o (for 1905 * backward compatibility) expected_attach_type, should have the default attach 1906 * type assigned to expected_attach_type for the latter case, so that it can be 1907 * validated later at attach time. 1908 * 1909 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1910 * prog type requires it but has some attach types that have to be backward 1911 * compatible. 1912 */ 1913 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1914 { 1915 switch (attr->prog_type) { 1916 case BPF_PROG_TYPE_CGROUP_SOCK: 1917 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1918 * exist so checking for non-zero is the way to go here. 1919 */ 1920 if (!attr->expected_attach_type) 1921 attr->expected_attach_type = 1922 BPF_CGROUP_INET_SOCK_CREATE; 1923 break; 1924 } 1925 } 1926 1927 static int 1928 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 1929 enum bpf_attach_type expected_attach_type, 1930 u32 btf_id, u32 prog_fd) 1931 { 1932 if (btf_id) { 1933 if (btf_id > BTF_MAX_TYPE) 1934 return -EINVAL; 1935 1936 switch (prog_type) { 1937 case BPF_PROG_TYPE_TRACING: 1938 case BPF_PROG_TYPE_STRUCT_OPS: 1939 case BPF_PROG_TYPE_EXT: 1940 break; 1941 default: 1942 return -EINVAL; 1943 } 1944 } 1945 1946 if (prog_fd && prog_type != BPF_PROG_TYPE_TRACING && 1947 prog_type != BPF_PROG_TYPE_EXT) 1948 return -EINVAL; 1949 1950 switch (prog_type) { 1951 case BPF_PROG_TYPE_CGROUP_SOCK: 1952 switch (expected_attach_type) { 1953 case BPF_CGROUP_INET_SOCK_CREATE: 1954 case BPF_CGROUP_INET4_POST_BIND: 1955 case BPF_CGROUP_INET6_POST_BIND: 1956 return 0; 1957 default: 1958 return -EINVAL; 1959 } 1960 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1961 switch (expected_attach_type) { 1962 case BPF_CGROUP_INET4_BIND: 1963 case BPF_CGROUP_INET6_BIND: 1964 case BPF_CGROUP_INET4_CONNECT: 1965 case BPF_CGROUP_INET6_CONNECT: 1966 case BPF_CGROUP_UDP4_SENDMSG: 1967 case BPF_CGROUP_UDP6_SENDMSG: 1968 case BPF_CGROUP_UDP4_RECVMSG: 1969 case BPF_CGROUP_UDP6_RECVMSG: 1970 return 0; 1971 default: 1972 return -EINVAL; 1973 } 1974 case BPF_PROG_TYPE_CGROUP_SKB: 1975 switch (expected_attach_type) { 1976 case BPF_CGROUP_INET_INGRESS: 1977 case BPF_CGROUP_INET_EGRESS: 1978 return 0; 1979 default: 1980 return -EINVAL; 1981 } 1982 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1983 switch (expected_attach_type) { 1984 case BPF_CGROUP_SETSOCKOPT: 1985 case BPF_CGROUP_GETSOCKOPT: 1986 return 0; 1987 default: 1988 return -EINVAL; 1989 } 1990 case BPF_PROG_TYPE_EXT: 1991 if (expected_attach_type) 1992 return -EINVAL; 1993 /* fallthrough */ 1994 default: 1995 return 0; 1996 } 1997 } 1998 1999 /* last field in 'union bpf_attr' used by this command */ 2000 #define BPF_PROG_LOAD_LAST_FIELD attach_prog_fd 2001 2002 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 2003 { 2004 enum bpf_prog_type type = attr->prog_type; 2005 struct bpf_prog *prog; 2006 int err; 2007 char license[128]; 2008 bool is_gpl; 2009 2010 if (CHECK_ATTR(BPF_PROG_LOAD)) 2011 return -EINVAL; 2012 2013 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2014 BPF_F_ANY_ALIGNMENT | 2015 BPF_F_TEST_STATE_FREQ | 2016 BPF_F_TEST_RND_HI32)) 2017 return -EINVAL; 2018 2019 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2020 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2021 !capable(CAP_SYS_ADMIN)) 2022 return -EPERM; 2023 2024 /* copy eBPF program license from user space */ 2025 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 2026 sizeof(license) - 1) < 0) 2027 return -EFAULT; 2028 license[sizeof(license) - 1] = 0; 2029 2030 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2031 is_gpl = license_is_gpl_compatible(license); 2032 2033 if (attr->insn_cnt == 0 || 2034 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2035 return -E2BIG; 2036 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2037 type != BPF_PROG_TYPE_CGROUP_SKB && 2038 !capable(CAP_SYS_ADMIN)) 2039 return -EPERM; 2040 2041 bpf_prog_load_fixup_attach_type(attr); 2042 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2043 attr->attach_btf_id, 2044 attr->attach_prog_fd)) 2045 return -EINVAL; 2046 2047 /* plain bpf_prog allocation */ 2048 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2049 if (!prog) 2050 return -ENOMEM; 2051 2052 prog->expected_attach_type = attr->expected_attach_type; 2053 prog->aux->attach_btf_id = attr->attach_btf_id; 2054 if (attr->attach_prog_fd) { 2055 struct bpf_prog *tgt_prog; 2056 2057 tgt_prog = bpf_prog_get(attr->attach_prog_fd); 2058 if (IS_ERR(tgt_prog)) { 2059 err = PTR_ERR(tgt_prog); 2060 goto free_prog_nouncharge; 2061 } 2062 prog->aux->linked_prog = tgt_prog; 2063 } 2064 2065 prog->aux->offload_requested = !!attr->prog_ifindex; 2066 2067 err = security_bpf_prog_alloc(prog->aux); 2068 if (err) 2069 goto free_prog_nouncharge; 2070 2071 err = bpf_prog_charge_memlock(prog); 2072 if (err) 2073 goto free_prog_sec; 2074 2075 prog->len = attr->insn_cnt; 2076 2077 err = -EFAULT; 2078 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 2079 bpf_prog_insn_size(prog)) != 0) 2080 goto free_prog; 2081 2082 prog->orig_prog = NULL; 2083 prog->jited = 0; 2084 2085 atomic64_set(&prog->aux->refcnt, 1); 2086 prog->gpl_compatible = is_gpl ? 1 : 0; 2087 2088 if (bpf_prog_is_dev_bound(prog->aux)) { 2089 err = bpf_prog_offload_init(prog, attr); 2090 if (err) 2091 goto free_prog; 2092 } 2093 2094 /* find program type: socket_filter vs tracing_filter */ 2095 err = find_prog_type(type, prog); 2096 if (err < 0) 2097 goto free_prog; 2098 2099 prog->aux->load_time = ktime_get_boottime_ns(); 2100 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name); 2101 if (err) 2102 goto free_prog; 2103 2104 /* run eBPF verifier */ 2105 err = bpf_check(&prog, attr, uattr); 2106 if (err < 0) 2107 goto free_used_maps; 2108 2109 prog = bpf_prog_select_runtime(prog, &err); 2110 if (err < 0) 2111 goto free_used_maps; 2112 2113 err = bpf_prog_alloc_id(prog); 2114 if (err) 2115 goto free_used_maps; 2116 2117 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2118 * effectively publicly exposed. However, retrieving via 2119 * bpf_prog_get_fd_by_id() will take another reference, 2120 * therefore it cannot be gone underneath us. 2121 * 2122 * Only for the time /after/ successful bpf_prog_new_fd() 2123 * and before returning to userspace, we might just hold 2124 * one reference and any parallel close on that fd could 2125 * rip everything out. Hence, below notifications must 2126 * happen before bpf_prog_new_fd(). 2127 * 2128 * Also, any failure handling from this point onwards must 2129 * be using bpf_prog_put() given the program is exposed. 2130 */ 2131 bpf_prog_kallsyms_add(prog); 2132 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2133 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2134 2135 err = bpf_prog_new_fd(prog); 2136 if (err < 0) 2137 bpf_prog_put(prog); 2138 return err; 2139 2140 free_used_maps: 2141 /* In case we have subprogs, we need to wait for a grace 2142 * period before we can tear down JIT memory since symbols 2143 * are already exposed under kallsyms. 2144 */ 2145 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2146 return err; 2147 free_prog: 2148 bpf_prog_uncharge_memlock(prog); 2149 free_prog_sec: 2150 security_bpf_prog_free(prog->aux); 2151 free_prog_nouncharge: 2152 bpf_prog_free(prog); 2153 return err; 2154 } 2155 2156 #define BPF_OBJ_LAST_FIELD file_flags 2157 2158 static int bpf_obj_pin(const union bpf_attr *attr) 2159 { 2160 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2161 return -EINVAL; 2162 2163 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2164 } 2165 2166 static int bpf_obj_get(const union bpf_attr *attr) 2167 { 2168 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2169 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2170 return -EINVAL; 2171 2172 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2173 attr->file_flags); 2174 } 2175 2176 struct bpf_link { 2177 atomic64_t refcnt; 2178 const struct bpf_link_ops *ops; 2179 struct bpf_prog *prog; 2180 struct work_struct work; 2181 }; 2182 2183 void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops, 2184 struct bpf_prog *prog) 2185 { 2186 atomic64_set(&link->refcnt, 1); 2187 link->ops = ops; 2188 link->prog = prog; 2189 } 2190 2191 void bpf_link_inc(struct bpf_link *link) 2192 { 2193 atomic64_inc(&link->refcnt); 2194 } 2195 2196 /* bpf_link_free is guaranteed to be called from process context */ 2197 static void bpf_link_free(struct bpf_link *link) 2198 { 2199 struct bpf_prog *prog; 2200 2201 /* remember prog locally, because release below will free link memory */ 2202 prog = link->prog; 2203 /* extra clean up and kfree of container link struct */ 2204 link->ops->release(link); 2205 /* no more accesing of link members after this point */ 2206 bpf_prog_put(prog); 2207 } 2208 2209 static void bpf_link_put_deferred(struct work_struct *work) 2210 { 2211 struct bpf_link *link = container_of(work, struct bpf_link, work); 2212 2213 bpf_link_free(link); 2214 } 2215 2216 /* bpf_link_put can be called from atomic context, but ensures that resources 2217 * are freed from process context 2218 */ 2219 void bpf_link_put(struct bpf_link *link) 2220 { 2221 if (!atomic64_dec_and_test(&link->refcnt)) 2222 return; 2223 2224 if (in_atomic()) { 2225 INIT_WORK(&link->work, bpf_link_put_deferred); 2226 schedule_work(&link->work); 2227 } else { 2228 bpf_link_free(link); 2229 } 2230 } 2231 2232 static int bpf_link_release(struct inode *inode, struct file *filp) 2233 { 2234 struct bpf_link *link = filp->private_data; 2235 2236 bpf_link_put(link); 2237 return 0; 2238 } 2239 2240 #ifdef CONFIG_PROC_FS 2241 static const struct bpf_link_ops bpf_raw_tp_lops; 2242 static const struct bpf_link_ops bpf_tracing_link_lops; 2243 static const struct bpf_link_ops bpf_xdp_link_lops; 2244 2245 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2246 { 2247 const struct bpf_link *link = filp->private_data; 2248 const struct bpf_prog *prog = link->prog; 2249 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2250 const char *link_type; 2251 2252 if (link->ops == &bpf_raw_tp_lops) 2253 link_type = "raw_tracepoint"; 2254 else if (link->ops == &bpf_tracing_link_lops) 2255 link_type = "tracing"; 2256 else 2257 link_type = "unknown"; 2258 2259 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2260 seq_printf(m, 2261 "link_type:\t%s\n" 2262 "prog_tag:\t%s\n" 2263 "prog_id:\t%u\n", 2264 link_type, 2265 prog_tag, 2266 prog->aux->id); 2267 } 2268 #endif 2269 2270 const struct file_operations bpf_link_fops = { 2271 #ifdef CONFIG_PROC_FS 2272 .show_fdinfo = bpf_link_show_fdinfo, 2273 #endif 2274 .release = bpf_link_release, 2275 .read = bpf_dummy_read, 2276 .write = bpf_dummy_write, 2277 }; 2278 2279 int bpf_link_new_fd(struct bpf_link *link) 2280 { 2281 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2282 } 2283 2284 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2285 { 2286 struct fd f = fdget(ufd); 2287 struct bpf_link *link; 2288 2289 if (!f.file) 2290 return ERR_PTR(-EBADF); 2291 if (f.file->f_op != &bpf_link_fops) { 2292 fdput(f); 2293 return ERR_PTR(-EINVAL); 2294 } 2295 2296 link = f.file->private_data; 2297 bpf_link_inc(link); 2298 fdput(f); 2299 2300 return link; 2301 } 2302 2303 struct bpf_tracing_link { 2304 struct bpf_link link; 2305 }; 2306 2307 static void bpf_tracing_link_release(struct bpf_link *link) 2308 { 2309 struct bpf_tracing_link *tr_link = 2310 container_of(link, struct bpf_tracing_link, link); 2311 2312 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog)); 2313 kfree(tr_link); 2314 } 2315 2316 static const struct bpf_link_ops bpf_tracing_link_lops = { 2317 .release = bpf_tracing_link_release, 2318 }; 2319 2320 static int bpf_tracing_prog_attach(struct bpf_prog *prog) 2321 { 2322 struct bpf_tracing_link *link; 2323 int link_fd, err; 2324 2325 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2326 prog->expected_attach_type != BPF_TRACE_FEXIT && 2327 prog->expected_attach_type != BPF_MODIFY_RETURN && 2328 prog->type != BPF_PROG_TYPE_EXT) { 2329 err = -EINVAL; 2330 goto out_put_prog; 2331 } 2332 2333 link = kzalloc(sizeof(*link), GFP_USER); 2334 if (!link) { 2335 err = -ENOMEM; 2336 goto out_put_prog; 2337 } 2338 bpf_link_init(&link->link, &bpf_tracing_link_lops, prog); 2339 2340 err = bpf_trampoline_link_prog(prog); 2341 if (err) 2342 goto out_free_link; 2343 2344 link_fd = bpf_link_new_fd(&link->link); 2345 if (link_fd < 0) { 2346 WARN_ON_ONCE(bpf_trampoline_unlink_prog(prog)); 2347 err = link_fd; 2348 goto out_free_link; 2349 } 2350 return link_fd; 2351 2352 out_free_link: 2353 kfree(link); 2354 out_put_prog: 2355 bpf_prog_put(prog); 2356 return err; 2357 } 2358 2359 struct bpf_raw_tp_link { 2360 struct bpf_link link; 2361 struct bpf_raw_event_map *btp; 2362 }; 2363 2364 static void bpf_raw_tp_link_release(struct bpf_link *link) 2365 { 2366 struct bpf_raw_tp_link *raw_tp = 2367 container_of(link, struct bpf_raw_tp_link, link); 2368 2369 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2370 bpf_put_raw_tracepoint(raw_tp->btp); 2371 kfree(raw_tp); 2372 } 2373 2374 static const struct bpf_link_ops bpf_raw_tp_lops = { 2375 .release = bpf_raw_tp_link_release, 2376 }; 2377 2378 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 2379 2380 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 2381 { 2382 struct bpf_raw_tp_link *raw_tp; 2383 struct bpf_raw_event_map *btp; 2384 struct bpf_prog *prog; 2385 const char *tp_name; 2386 char buf[128]; 2387 int link_fd, err; 2388 2389 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 2390 return -EINVAL; 2391 2392 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 2393 if (IS_ERR(prog)) 2394 return PTR_ERR(prog); 2395 2396 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT && 2397 prog->type != BPF_PROG_TYPE_TRACING && 2398 prog->type != BPF_PROG_TYPE_EXT && 2399 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) { 2400 err = -EINVAL; 2401 goto out_put_prog; 2402 } 2403 2404 if (prog->type == BPF_PROG_TYPE_TRACING || 2405 prog->type == BPF_PROG_TYPE_EXT) { 2406 if (attr->raw_tracepoint.name) { 2407 /* The attach point for this category of programs 2408 * should be specified via btf_id during program load. 2409 */ 2410 err = -EINVAL; 2411 goto out_put_prog; 2412 } 2413 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 2414 tp_name = prog->aux->attach_func_name; 2415 else 2416 return bpf_tracing_prog_attach(prog); 2417 } else { 2418 if (strncpy_from_user(buf, 2419 u64_to_user_ptr(attr->raw_tracepoint.name), 2420 sizeof(buf) - 1) < 0) { 2421 err = -EFAULT; 2422 goto out_put_prog; 2423 } 2424 buf[sizeof(buf) - 1] = 0; 2425 tp_name = buf; 2426 } 2427 2428 btp = bpf_get_raw_tracepoint(tp_name); 2429 if (!btp) { 2430 err = -ENOENT; 2431 goto out_put_prog; 2432 } 2433 2434 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); 2435 if (!raw_tp) { 2436 err = -ENOMEM; 2437 goto out_put_btp; 2438 } 2439 bpf_link_init(&raw_tp->link, &bpf_raw_tp_lops, prog); 2440 raw_tp->btp = btp; 2441 2442 err = bpf_probe_register(raw_tp->btp, prog); 2443 if (err) 2444 goto out_free_tp; 2445 2446 link_fd = bpf_link_new_fd(&raw_tp->link); 2447 if (link_fd < 0) { 2448 bpf_probe_unregister(raw_tp->btp, prog); 2449 err = link_fd; 2450 goto out_free_tp; 2451 } 2452 return link_fd; 2453 2454 out_free_tp: 2455 kfree(raw_tp); 2456 out_put_btp: 2457 bpf_put_raw_tracepoint(btp); 2458 out_put_prog: 2459 bpf_prog_put(prog); 2460 return err; 2461 } 2462 2463 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 2464 enum bpf_attach_type attach_type) 2465 { 2466 switch (prog->type) { 2467 case BPF_PROG_TYPE_CGROUP_SOCK: 2468 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2469 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2470 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 2471 case BPF_PROG_TYPE_CGROUP_SKB: 2472 return prog->enforce_expected_attach_type && 2473 prog->expected_attach_type != attach_type ? 2474 -EINVAL : 0; 2475 default: 2476 return 0; 2477 } 2478 } 2479 2480 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 2481 2482 #define BPF_F_ATTACH_MASK \ 2483 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 2484 2485 static int bpf_prog_attach(const union bpf_attr *attr) 2486 { 2487 enum bpf_prog_type ptype; 2488 struct bpf_prog *prog; 2489 int ret; 2490 2491 if (!capable(CAP_NET_ADMIN)) 2492 return -EPERM; 2493 2494 if (CHECK_ATTR(BPF_PROG_ATTACH)) 2495 return -EINVAL; 2496 2497 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 2498 return -EINVAL; 2499 2500 switch (attr->attach_type) { 2501 case BPF_CGROUP_INET_INGRESS: 2502 case BPF_CGROUP_INET_EGRESS: 2503 ptype = BPF_PROG_TYPE_CGROUP_SKB; 2504 break; 2505 case BPF_CGROUP_INET_SOCK_CREATE: 2506 case BPF_CGROUP_INET4_POST_BIND: 2507 case BPF_CGROUP_INET6_POST_BIND: 2508 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 2509 break; 2510 case BPF_CGROUP_INET4_BIND: 2511 case BPF_CGROUP_INET6_BIND: 2512 case BPF_CGROUP_INET4_CONNECT: 2513 case BPF_CGROUP_INET6_CONNECT: 2514 case BPF_CGROUP_UDP4_SENDMSG: 2515 case BPF_CGROUP_UDP6_SENDMSG: 2516 case BPF_CGROUP_UDP4_RECVMSG: 2517 case BPF_CGROUP_UDP6_RECVMSG: 2518 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 2519 break; 2520 case BPF_CGROUP_SOCK_OPS: 2521 ptype = BPF_PROG_TYPE_SOCK_OPS; 2522 break; 2523 case BPF_CGROUP_DEVICE: 2524 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 2525 break; 2526 case BPF_SK_MSG_VERDICT: 2527 ptype = BPF_PROG_TYPE_SK_MSG; 2528 break; 2529 case BPF_SK_SKB_STREAM_PARSER: 2530 case BPF_SK_SKB_STREAM_VERDICT: 2531 ptype = BPF_PROG_TYPE_SK_SKB; 2532 break; 2533 case BPF_LIRC_MODE2: 2534 ptype = BPF_PROG_TYPE_LIRC_MODE2; 2535 break; 2536 case BPF_FLOW_DISSECTOR: 2537 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR; 2538 break; 2539 case BPF_CGROUP_SYSCTL: 2540 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 2541 break; 2542 case BPF_CGROUP_GETSOCKOPT: 2543 case BPF_CGROUP_SETSOCKOPT: 2544 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 2545 break; 2546 default: 2547 return -EINVAL; 2548 } 2549 2550 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 2551 if (IS_ERR(prog)) 2552 return PTR_ERR(prog); 2553 2554 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 2555 bpf_prog_put(prog); 2556 return -EINVAL; 2557 } 2558 2559 switch (ptype) { 2560 case BPF_PROG_TYPE_SK_SKB: 2561 case BPF_PROG_TYPE_SK_MSG: 2562 ret = sock_map_get_from_fd(attr, prog); 2563 break; 2564 case BPF_PROG_TYPE_LIRC_MODE2: 2565 ret = lirc_prog_attach(attr, prog); 2566 break; 2567 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2568 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 2569 break; 2570 default: 2571 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 2572 } 2573 2574 if (ret) 2575 bpf_prog_put(prog); 2576 return ret; 2577 } 2578 2579 #define BPF_PROG_DETACH_LAST_FIELD attach_type 2580 2581 static int bpf_prog_detach(const union bpf_attr *attr) 2582 { 2583 enum bpf_prog_type ptype; 2584 2585 if (!capable(CAP_NET_ADMIN)) 2586 return -EPERM; 2587 2588 if (CHECK_ATTR(BPF_PROG_DETACH)) 2589 return -EINVAL; 2590 2591 switch (attr->attach_type) { 2592 case BPF_CGROUP_INET_INGRESS: 2593 case BPF_CGROUP_INET_EGRESS: 2594 ptype = BPF_PROG_TYPE_CGROUP_SKB; 2595 break; 2596 case BPF_CGROUP_INET_SOCK_CREATE: 2597 case BPF_CGROUP_INET4_POST_BIND: 2598 case BPF_CGROUP_INET6_POST_BIND: 2599 ptype = BPF_PROG_TYPE_CGROUP_SOCK; 2600 break; 2601 case BPF_CGROUP_INET4_BIND: 2602 case BPF_CGROUP_INET6_BIND: 2603 case BPF_CGROUP_INET4_CONNECT: 2604 case BPF_CGROUP_INET6_CONNECT: 2605 case BPF_CGROUP_UDP4_SENDMSG: 2606 case BPF_CGROUP_UDP6_SENDMSG: 2607 case BPF_CGROUP_UDP4_RECVMSG: 2608 case BPF_CGROUP_UDP6_RECVMSG: 2609 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 2610 break; 2611 case BPF_CGROUP_SOCK_OPS: 2612 ptype = BPF_PROG_TYPE_SOCK_OPS; 2613 break; 2614 case BPF_CGROUP_DEVICE: 2615 ptype = BPF_PROG_TYPE_CGROUP_DEVICE; 2616 break; 2617 case BPF_SK_MSG_VERDICT: 2618 return sock_map_get_from_fd(attr, NULL); 2619 case BPF_SK_SKB_STREAM_PARSER: 2620 case BPF_SK_SKB_STREAM_VERDICT: 2621 return sock_map_get_from_fd(attr, NULL); 2622 case BPF_LIRC_MODE2: 2623 return lirc_prog_detach(attr); 2624 case BPF_FLOW_DISSECTOR: 2625 return skb_flow_dissector_bpf_prog_detach(attr); 2626 case BPF_CGROUP_SYSCTL: 2627 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL; 2628 break; 2629 case BPF_CGROUP_GETSOCKOPT: 2630 case BPF_CGROUP_SETSOCKOPT: 2631 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT; 2632 break; 2633 default: 2634 return -EINVAL; 2635 } 2636 2637 return cgroup_bpf_prog_detach(attr, ptype); 2638 } 2639 2640 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 2641 2642 static int bpf_prog_query(const union bpf_attr *attr, 2643 union bpf_attr __user *uattr) 2644 { 2645 if (!capable(CAP_NET_ADMIN)) 2646 return -EPERM; 2647 if (CHECK_ATTR(BPF_PROG_QUERY)) 2648 return -EINVAL; 2649 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2650 return -EINVAL; 2651 2652 switch (attr->query.attach_type) { 2653 case BPF_CGROUP_INET_INGRESS: 2654 case BPF_CGROUP_INET_EGRESS: 2655 case BPF_CGROUP_INET_SOCK_CREATE: 2656 case BPF_CGROUP_INET4_BIND: 2657 case BPF_CGROUP_INET6_BIND: 2658 case BPF_CGROUP_INET4_POST_BIND: 2659 case BPF_CGROUP_INET6_POST_BIND: 2660 case BPF_CGROUP_INET4_CONNECT: 2661 case BPF_CGROUP_INET6_CONNECT: 2662 case BPF_CGROUP_UDP4_SENDMSG: 2663 case BPF_CGROUP_UDP6_SENDMSG: 2664 case BPF_CGROUP_UDP4_RECVMSG: 2665 case BPF_CGROUP_UDP6_RECVMSG: 2666 case BPF_CGROUP_SOCK_OPS: 2667 case BPF_CGROUP_DEVICE: 2668 case BPF_CGROUP_SYSCTL: 2669 case BPF_CGROUP_GETSOCKOPT: 2670 case BPF_CGROUP_SETSOCKOPT: 2671 break; 2672 case BPF_LIRC_MODE2: 2673 return lirc_prog_query(attr, uattr); 2674 case BPF_FLOW_DISSECTOR: 2675 return skb_flow_dissector_prog_query(attr, uattr); 2676 default: 2677 return -EINVAL; 2678 } 2679 2680 return cgroup_bpf_prog_query(attr, uattr); 2681 } 2682 2683 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2684 2685 static int bpf_prog_test_run(const union bpf_attr *attr, 2686 union bpf_attr __user *uattr) 2687 { 2688 struct bpf_prog *prog; 2689 int ret = -ENOTSUPP; 2690 2691 if (!capable(CAP_SYS_ADMIN)) 2692 return -EPERM; 2693 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2694 return -EINVAL; 2695 2696 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2697 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2698 return -EINVAL; 2699 2700 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2701 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2702 return -EINVAL; 2703 2704 prog = bpf_prog_get(attr->test.prog_fd); 2705 if (IS_ERR(prog)) 2706 return PTR_ERR(prog); 2707 2708 if (prog->aux->ops->test_run) 2709 ret = prog->aux->ops->test_run(prog, attr, uattr); 2710 2711 bpf_prog_put(prog); 2712 return ret; 2713 } 2714 2715 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2716 2717 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2718 union bpf_attr __user *uattr, 2719 struct idr *idr, 2720 spinlock_t *lock) 2721 { 2722 u32 next_id = attr->start_id; 2723 int err = 0; 2724 2725 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2726 return -EINVAL; 2727 2728 if (!capable(CAP_SYS_ADMIN)) 2729 return -EPERM; 2730 2731 next_id++; 2732 spin_lock_bh(lock); 2733 if (!idr_get_next(idr, &next_id)) 2734 err = -ENOENT; 2735 spin_unlock_bh(lock); 2736 2737 if (!err) 2738 err = put_user(next_id, &uattr->next_id); 2739 2740 return err; 2741 } 2742 2743 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2744 2745 struct bpf_prog *bpf_prog_by_id(u32 id) 2746 { 2747 struct bpf_prog *prog; 2748 2749 if (!id) 2750 return ERR_PTR(-ENOENT); 2751 2752 spin_lock_bh(&prog_idr_lock); 2753 prog = idr_find(&prog_idr, id); 2754 if (prog) 2755 prog = bpf_prog_inc_not_zero(prog); 2756 else 2757 prog = ERR_PTR(-ENOENT); 2758 spin_unlock_bh(&prog_idr_lock); 2759 return prog; 2760 } 2761 2762 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2763 { 2764 struct bpf_prog *prog; 2765 u32 id = attr->prog_id; 2766 int fd; 2767 2768 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2769 return -EINVAL; 2770 2771 if (!capable(CAP_SYS_ADMIN)) 2772 return -EPERM; 2773 2774 prog = bpf_prog_by_id(id); 2775 if (IS_ERR(prog)) 2776 return PTR_ERR(prog); 2777 2778 fd = bpf_prog_new_fd(prog); 2779 if (fd < 0) 2780 bpf_prog_put(prog); 2781 2782 return fd; 2783 } 2784 2785 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2786 2787 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2788 { 2789 struct bpf_map *map; 2790 u32 id = attr->map_id; 2791 int f_flags; 2792 int fd; 2793 2794 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2795 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2796 return -EINVAL; 2797 2798 if (!capable(CAP_SYS_ADMIN)) 2799 return -EPERM; 2800 2801 f_flags = bpf_get_file_flag(attr->open_flags); 2802 if (f_flags < 0) 2803 return f_flags; 2804 2805 spin_lock_bh(&map_idr_lock); 2806 map = idr_find(&map_idr, id); 2807 if (map) 2808 map = __bpf_map_inc_not_zero(map, true); 2809 else 2810 map = ERR_PTR(-ENOENT); 2811 spin_unlock_bh(&map_idr_lock); 2812 2813 if (IS_ERR(map)) 2814 return PTR_ERR(map); 2815 2816 fd = bpf_map_new_fd(map, f_flags); 2817 if (fd < 0) 2818 bpf_map_put_with_uref(map); 2819 2820 return fd; 2821 } 2822 2823 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2824 unsigned long addr, u32 *off, 2825 u32 *type) 2826 { 2827 const struct bpf_map *map; 2828 int i; 2829 2830 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2831 map = prog->aux->used_maps[i]; 2832 if (map == (void *)addr) { 2833 *type = BPF_PSEUDO_MAP_FD; 2834 return map; 2835 } 2836 if (!map->ops->map_direct_value_meta) 2837 continue; 2838 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2839 *type = BPF_PSEUDO_MAP_VALUE; 2840 return map; 2841 } 2842 } 2843 2844 return NULL; 2845 } 2846 2847 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2848 { 2849 const struct bpf_map *map; 2850 struct bpf_insn *insns; 2851 u32 off, type; 2852 u64 imm; 2853 int i; 2854 2855 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2856 GFP_USER); 2857 if (!insns) 2858 return insns; 2859 2860 for (i = 0; i < prog->len; i++) { 2861 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2862 insns[i].code = BPF_JMP | BPF_CALL; 2863 insns[i].imm = BPF_FUNC_tail_call; 2864 /* fall-through */ 2865 } 2866 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2867 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2868 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2869 insns[i].code = BPF_JMP | BPF_CALL; 2870 if (!bpf_dump_raw_ok()) 2871 insns[i].imm = 0; 2872 continue; 2873 } 2874 2875 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2876 continue; 2877 2878 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2879 map = bpf_map_from_imm(prog, imm, &off, &type); 2880 if (map) { 2881 insns[i].src_reg = type; 2882 insns[i].imm = map->id; 2883 insns[i + 1].imm = off; 2884 continue; 2885 } 2886 } 2887 2888 return insns; 2889 } 2890 2891 static int set_info_rec_size(struct bpf_prog_info *info) 2892 { 2893 /* 2894 * Ensure info.*_rec_size is the same as kernel expected size 2895 * 2896 * or 2897 * 2898 * Only allow zero *_rec_size if both _rec_size and _cnt are 2899 * zero. In this case, the kernel will set the expected 2900 * _rec_size back to the info. 2901 */ 2902 2903 if ((info->nr_func_info || info->func_info_rec_size) && 2904 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2905 return -EINVAL; 2906 2907 if ((info->nr_line_info || info->line_info_rec_size) && 2908 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2909 return -EINVAL; 2910 2911 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2912 info->jited_line_info_rec_size != sizeof(__u64)) 2913 return -EINVAL; 2914 2915 info->func_info_rec_size = sizeof(struct bpf_func_info); 2916 info->line_info_rec_size = sizeof(struct bpf_line_info); 2917 info->jited_line_info_rec_size = sizeof(__u64); 2918 2919 return 0; 2920 } 2921 2922 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2923 const union bpf_attr *attr, 2924 union bpf_attr __user *uattr) 2925 { 2926 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2927 struct bpf_prog_info info = {}; 2928 u32 info_len = attr->info.info_len; 2929 struct bpf_prog_stats stats; 2930 char __user *uinsns; 2931 u32 ulen; 2932 int err; 2933 2934 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2935 if (err) 2936 return err; 2937 info_len = min_t(u32, sizeof(info), info_len); 2938 2939 if (copy_from_user(&info, uinfo, info_len)) 2940 return -EFAULT; 2941 2942 info.type = prog->type; 2943 info.id = prog->aux->id; 2944 info.load_time = prog->aux->load_time; 2945 info.created_by_uid = from_kuid_munged(current_user_ns(), 2946 prog->aux->user->uid); 2947 info.gpl_compatible = prog->gpl_compatible; 2948 2949 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 2950 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 2951 2952 ulen = info.nr_map_ids; 2953 info.nr_map_ids = prog->aux->used_map_cnt; 2954 ulen = min_t(u32, info.nr_map_ids, ulen); 2955 if (ulen) { 2956 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 2957 u32 i; 2958 2959 for (i = 0; i < ulen; i++) 2960 if (put_user(prog->aux->used_maps[i]->id, 2961 &user_map_ids[i])) 2962 return -EFAULT; 2963 } 2964 2965 err = set_info_rec_size(&info); 2966 if (err) 2967 return err; 2968 2969 bpf_prog_get_stats(prog, &stats); 2970 info.run_time_ns = stats.nsecs; 2971 info.run_cnt = stats.cnt; 2972 2973 if (!capable(CAP_SYS_ADMIN)) { 2974 info.jited_prog_len = 0; 2975 info.xlated_prog_len = 0; 2976 info.nr_jited_ksyms = 0; 2977 info.nr_jited_func_lens = 0; 2978 info.nr_func_info = 0; 2979 info.nr_line_info = 0; 2980 info.nr_jited_line_info = 0; 2981 goto done; 2982 } 2983 2984 ulen = info.xlated_prog_len; 2985 info.xlated_prog_len = bpf_prog_insn_size(prog); 2986 if (info.xlated_prog_len && ulen) { 2987 struct bpf_insn *insns_sanitized; 2988 bool fault; 2989 2990 if (prog->blinded && !bpf_dump_raw_ok()) { 2991 info.xlated_prog_insns = 0; 2992 goto done; 2993 } 2994 insns_sanitized = bpf_insn_prepare_dump(prog); 2995 if (!insns_sanitized) 2996 return -ENOMEM; 2997 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 2998 ulen = min_t(u32, info.xlated_prog_len, ulen); 2999 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3000 kfree(insns_sanitized); 3001 if (fault) 3002 return -EFAULT; 3003 } 3004 3005 if (bpf_prog_is_dev_bound(prog->aux)) { 3006 err = bpf_prog_offload_info_fill(&info, prog); 3007 if (err) 3008 return err; 3009 goto done; 3010 } 3011 3012 /* NOTE: the following code is supposed to be skipped for offload. 3013 * bpf_prog_offload_info_fill() is the place to fill similar fields 3014 * for offload. 3015 */ 3016 ulen = info.jited_prog_len; 3017 if (prog->aux->func_cnt) { 3018 u32 i; 3019 3020 info.jited_prog_len = 0; 3021 for (i = 0; i < prog->aux->func_cnt; i++) 3022 info.jited_prog_len += prog->aux->func[i]->jited_len; 3023 } else { 3024 info.jited_prog_len = prog->jited_len; 3025 } 3026 3027 if (info.jited_prog_len && ulen) { 3028 if (bpf_dump_raw_ok()) { 3029 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3030 ulen = min_t(u32, info.jited_prog_len, ulen); 3031 3032 /* for multi-function programs, copy the JITed 3033 * instructions for all the functions 3034 */ 3035 if (prog->aux->func_cnt) { 3036 u32 len, free, i; 3037 u8 *img; 3038 3039 free = ulen; 3040 for (i = 0; i < prog->aux->func_cnt; i++) { 3041 len = prog->aux->func[i]->jited_len; 3042 len = min_t(u32, len, free); 3043 img = (u8 *) prog->aux->func[i]->bpf_func; 3044 if (copy_to_user(uinsns, img, len)) 3045 return -EFAULT; 3046 uinsns += len; 3047 free -= len; 3048 if (!free) 3049 break; 3050 } 3051 } else { 3052 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3053 return -EFAULT; 3054 } 3055 } else { 3056 info.jited_prog_insns = 0; 3057 } 3058 } 3059 3060 ulen = info.nr_jited_ksyms; 3061 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3062 if (ulen) { 3063 if (bpf_dump_raw_ok()) { 3064 unsigned long ksym_addr; 3065 u64 __user *user_ksyms; 3066 u32 i; 3067 3068 /* copy the address of the kernel symbol 3069 * corresponding to each function 3070 */ 3071 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3072 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3073 if (prog->aux->func_cnt) { 3074 for (i = 0; i < ulen; i++) { 3075 ksym_addr = (unsigned long) 3076 prog->aux->func[i]->bpf_func; 3077 if (put_user((u64) ksym_addr, 3078 &user_ksyms[i])) 3079 return -EFAULT; 3080 } 3081 } else { 3082 ksym_addr = (unsigned long) prog->bpf_func; 3083 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3084 return -EFAULT; 3085 } 3086 } else { 3087 info.jited_ksyms = 0; 3088 } 3089 } 3090 3091 ulen = info.nr_jited_func_lens; 3092 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3093 if (ulen) { 3094 if (bpf_dump_raw_ok()) { 3095 u32 __user *user_lens; 3096 u32 func_len, i; 3097 3098 /* copy the JITed image lengths for each function */ 3099 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3100 user_lens = u64_to_user_ptr(info.jited_func_lens); 3101 if (prog->aux->func_cnt) { 3102 for (i = 0; i < ulen; i++) { 3103 func_len = 3104 prog->aux->func[i]->jited_len; 3105 if (put_user(func_len, &user_lens[i])) 3106 return -EFAULT; 3107 } 3108 } else { 3109 func_len = prog->jited_len; 3110 if (put_user(func_len, &user_lens[0])) 3111 return -EFAULT; 3112 } 3113 } else { 3114 info.jited_func_lens = 0; 3115 } 3116 } 3117 3118 if (prog->aux->btf) 3119 info.btf_id = btf_id(prog->aux->btf); 3120 3121 ulen = info.nr_func_info; 3122 info.nr_func_info = prog->aux->func_info_cnt; 3123 if (info.nr_func_info && ulen) { 3124 char __user *user_finfo; 3125 3126 user_finfo = u64_to_user_ptr(info.func_info); 3127 ulen = min_t(u32, info.nr_func_info, ulen); 3128 if (copy_to_user(user_finfo, prog->aux->func_info, 3129 info.func_info_rec_size * ulen)) 3130 return -EFAULT; 3131 } 3132 3133 ulen = info.nr_line_info; 3134 info.nr_line_info = prog->aux->nr_linfo; 3135 if (info.nr_line_info && ulen) { 3136 __u8 __user *user_linfo; 3137 3138 user_linfo = u64_to_user_ptr(info.line_info); 3139 ulen = min_t(u32, info.nr_line_info, ulen); 3140 if (copy_to_user(user_linfo, prog->aux->linfo, 3141 info.line_info_rec_size * ulen)) 3142 return -EFAULT; 3143 } 3144 3145 ulen = info.nr_jited_line_info; 3146 if (prog->aux->jited_linfo) 3147 info.nr_jited_line_info = prog->aux->nr_linfo; 3148 else 3149 info.nr_jited_line_info = 0; 3150 if (info.nr_jited_line_info && ulen) { 3151 if (bpf_dump_raw_ok()) { 3152 __u64 __user *user_linfo; 3153 u32 i; 3154 3155 user_linfo = u64_to_user_ptr(info.jited_line_info); 3156 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3157 for (i = 0; i < ulen; i++) { 3158 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3159 &user_linfo[i])) 3160 return -EFAULT; 3161 } 3162 } else { 3163 info.jited_line_info = 0; 3164 } 3165 } 3166 3167 ulen = info.nr_prog_tags; 3168 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3169 if (ulen) { 3170 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3171 u32 i; 3172 3173 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3174 ulen = min_t(u32, info.nr_prog_tags, ulen); 3175 if (prog->aux->func_cnt) { 3176 for (i = 0; i < ulen; i++) { 3177 if (copy_to_user(user_prog_tags[i], 3178 prog->aux->func[i]->tag, 3179 BPF_TAG_SIZE)) 3180 return -EFAULT; 3181 } 3182 } else { 3183 if (copy_to_user(user_prog_tags[0], 3184 prog->tag, BPF_TAG_SIZE)) 3185 return -EFAULT; 3186 } 3187 } 3188 3189 done: 3190 if (copy_to_user(uinfo, &info, info_len) || 3191 put_user(info_len, &uattr->info.info_len)) 3192 return -EFAULT; 3193 3194 return 0; 3195 } 3196 3197 static int bpf_map_get_info_by_fd(struct bpf_map *map, 3198 const union bpf_attr *attr, 3199 union bpf_attr __user *uattr) 3200 { 3201 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3202 struct bpf_map_info info = {}; 3203 u32 info_len = attr->info.info_len; 3204 int err; 3205 3206 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 3207 if (err) 3208 return err; 3209 info_len = min_t(u32, sizeof(info), info_len); 3210 3211 info.type = map->map_type; 3212 info.id = map->id; 3213 info.key_size = map->key_size; 3214 info.value_size = map->value_size; 3215 info.max_entries = map->max_entries; 3216 info.map_flags = map->map_flags; 3217 memcpy(info.name, map->name, sizeof(map->name)); 3218 3219 if (map->btf) { 3220 info.btf_id = btf_id(map->btf); 3221 info.btf_key_type_id = map->btf_key_type_id; 3222 info.btf_value_type_id = map->btf_value_type_id; 3223 } 3224 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3225 3226 if (bpf_map_is_dev_bound(map)) { 3227 err = bpf_map_offload_info_fill(&info, map); 3228 if (err) 3229 return err; 3230 } 3231 3232 if (copy_to_user(uinfo, &info, info_len) || 3233 put_user(info_len, &uattr->info.info_len)) 3234 return -EFAULT; 3235 3236 return 0; 3237 } 3238 3239 static int bpf_btf_get_info_by_fd(struct btf *btf, 3240 const union bpf_attr *attr, 3241 union bpf_attr __user *uattr) 3242 { 3243 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3244 u32 info_len = attr->info.info_len; 3245 int err; 3246 3247 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 3248 if (err) 3249 return err; 3250 3251 return btf_get_info_by_fd(btf, attr, uattr); 3252 } 3253 3254 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 3255 3256 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 3257 union bpf_attr __user *uattr) 3258 { 3259 int ufd = attr->info.bpf_fd; 3260 struct fd f; 3261 int err; 3262 3263 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 3264 return -EINVAL; 3265 3266 f = fdget(ufd); 3267 if (!f.file) 3268 return -EBADFD; 3269 3270 if (f.file->f_op == &bpf_prog_fops) 3271 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 3272 uattr); 3273 else if (f.file->f_op == &bpf_map_fops) 3274 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 3275 uattr); 3276 else if (f.file->f_op == &btf_fops) 3277 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 3278 else 3279 err = -EINVAL; 3280 3281 fdput(f); 3282 return err; 3283 } 3284 3285 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 3286 3287 static int bpf_btf_load(const union bpf_attr *attr) 3288 { 3289 if (CHECK_ATTR(BPF_BTF_LOAD)) 3290 return -EINVAL; 3291 3292 if (!capable(CAP_SYS_ADMIN)) 3293 return -EPERM; 3294 3295 return btf_new_fd(attr); 3296 } 3297 3298 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 3299 3300 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 3301 { 3302 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 3303 return -EINVAL; 3304 3305 if (!capable(CAP_SYS_ADMIN)) 3306 return -EPERM; 3307 3308 return btf_get_fd_by_id(attr->btf_id); 3309 } 3310 3311 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 3312 union bpf_attr __user *uattr, 3313 u32 prog_id, u32 fd_type, 3314 const char *buf, u64 probe_offset, 3315 u64 probe_addr) 3316 { 3317 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 3318 u32 len = buf ? strlen(buf) : 0, input_len; 3319 int err = 0; 3320 3321 if (put_user(len, &uattr->task_fd_query.buf_len)) 3322 return -EFAULT; 3323 input_len = attr->task_fd_query.buf_len; 3324 if (input_len && ubuf) { 3325 if (!len) { 3326 /* nothing to copy, just make ubuf NULL terminated */ 3327 char zero = '\0'; 3328 3329 if (put_user(zero, ubuf)) 3330 return -EFAULT; 3331 } else if (input_len >= len + 1) { 3332 /* ubuf can hold the string with NULL terminator */ 3333 if (copy_to_user(ubuf, buf, len + 1)) 3334 return -EFAULT; 3335 } else { 3336 /* ubuf cannot hold the string with NULL terminator, 3337 * do a partial copy with NULL terminator. 3338 */ 3339 char zero = '\0'; 3340 3341 err = -ENOSPC; 3342 if (copy_to_user(ubuf, buf, input_len - 1)) 3343 return -EFAULT; 3344 if (put_user(zero, ubuf + input_len - 1)) 3345 return -EFAULT; 3346 } 3347 } 3348 3349 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 3350 put_user(fd_type, &uattr->task_fd_query.fd_type) || 3351 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 3352 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 3353 return -EFAULT; 3354 3355 return err; 3356 } 3357 3358 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 3359 3360 static int bpf_task_fd_query(const union bpf_attr *attr, 3361 union bpf_attr __user *uattr) 3362 { 3363 pid_t pid = attr->task_fd_query.pid; 3364 u32 fd = attr->task_fd_query.fd; 3365 const struct perf_event *event; 3366 struct files_struct *files; 3367 struct task_struct *task; 3368 struct file *file; 3369 int err; 3370 3371 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 3372 return -EINVAL; 3373 3374 if (!capable(CAP_SYS_ADMIN)) 3375 return -EPERM; 3376 3377 if (attr->task_fd_query.flags != 0) 3378 return -EINVAL; 3379 3380 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 3381 if (!task) 3382 return -ENOENT; 3383 3384 files = get_files_struct(task); 3385 put_task_struct(task); 3386 if (!files) 3387 return -ENOENT; 3388 3389 err = 0; 3390 spin_lock(&files->file_lock); 3391 file = fcheck_files(files, fd); 3392 if (!file) 3393 err = -EBADF; 3394 else 3395 get_file(file); 3396 spin_unlock(&files->file_lock); 3397 put_files_struct(files); 3398 3399 if (err) 3400 goto out; 3401 3402 if (file->f_op == &bpf_link_fops) { 3403 struct bpf_link *link = file->private_data; 3404 3405 if (link->ops == &bpf_raw_tp_lops) { 3406 struct bpf_raw_tp_link *raw_tp = 3407 container_of(link, struct bpf_raw_tp_link, link); 3408 struct bpf_raw_event_map *btp = raw_tp->btp; 3409 3410 err = bpf_task_fd_query_copy(attr, uattr, 3411 raw_tp->link.prog->aux->id, 3412 BPF_FD_TYPE_RAW_TRACEPOINT, 3413 btp->tp->name, 0, 0); 3414 goto put_file; 3415 } 3416 goto out_not_supp; 3417 } 3418 3419 event = perf_get_event(file); 3420 if (!IS_ERR(event)) { 3421 u64 probe_offset, probe_addr; 3422 u32 prog_id, fd_type; 3423 const char *buf; 3424 3425 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 3426 &buf, &probe_offset, 3427 &probe_addr); 3428 if (!err) 3429 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 3430 fd_type, buf, 3431 probe_offset, 3432 probe_addr); 3433 goto put_file; 3434 } 3435 3436 out_not_supp: 3437 err = -ENOTSUPP; 3438 put_file: 3439 fput(file); 3440 out: 3441 return err; 3442 } 3443 3444 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 3445 3446 #define BPF_DO_BATCH(fn) \ 3447 do { \ 3448 if (!fn) { \ 3449 err = -ENOTSUPP; \ 3450 goto err_put; \ 3451 } \ 3452 err = fn(map, attr, uattr); \ 3453 } while (0) 3454 3455 static int bpf_map_do_batch(const union bpf_attr *attr, 3456 union bpf_attr __user *uattr, 3457 int cmd) 3458 { 3459 struct bpf_map *map; 3460 int err, ufd; 3461 struct fd f; 3462 3463 if (CHECK_ATTR(BPF_MAP_BATCH)) 3464 return -EINVAL; 3465 3466 ufd = attr->batch.map_fd; 3467 f = fdget(ufd); 3468 map = __bpf_map_get(f); 3469 if (IS_ERR(map)) 3470 return PTR_ERR(map); 3471 3472 if ((cmd == BPF_MAP_LOOKUP_BATCH || 3473 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) && 3474 !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 3475 err = -EPERM; 3476 goto err_put; 3477 } 3478 3479 if (cmd != BPF_MAP_LOOKUP_BATCH && 3480 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 3481 err = -EPERM; 3482 goto err_put; 3483 } 3484 3485 if (cmd == BPF_MAP_LOOKUP_BATCH) 3486 BPF_DO_BATCH(map->ops->map_lookup_batch); 3487 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 3488 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 3489 else if (cmd == BPF_MAP_UPDATE_BATCH) 3490 BPF_DO_BATCH(map->ops->map_update_batch); 3491 else 3492 BPF_DO_BATCH(map->ops->map_delete_batch); 3493 3494 err_put: 3495 fdput(f); 3496 return err; 3497 } 3498 3499 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 3500 { 3501 union bpf_attr attr = {}; 3502 int err; 3503 3504 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 3505 return -EPERM; 3506 3507 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 3508 if (err) 3509 return err; 3510 size = min_t(u32, size, sizeof(attr)); 3511 3512 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 3513 if (copy_from_user(&attr, uattr, size) != 0) 3514 return -EFAULT; 3515 3516 err = security_bpf(cmd, &attr, size); 3517 if (err < 0) 3518 return err; 3519 3520 switch (cmd) { 3521 case BPF_MAP_CREATE: 3522 err = map_create(&attr); 3523 break; 3524 case BPF_MAP_LOOKUP_ELEM: 3525 err = map_lookup_elem(&attr); 3526 break; 3527 case BPF_MAP_UPDATE_ELEM: 3528 err = map_update_elem(&attr); 3529 break; 3530 case BPF_MAP_DELETE_ELEM: 3531 err = map_delete_elem(&attr); 3532 break; 3533 case BPF_MAP_GET_NEXT_KEY: 3534 err = map_get_next_key(&attr); 3535 break; 3536 case BPF_MAP_FREEZE: 3537 err = map_freeze(&attr); 3538 break; 3539 case BPF_PROG_LOAD: 3540 err = bpf_prog_load(&attr, uattr); 3541 break; 3542 case BPF_OBJ_PIN: 3543 err = bpf_obj_pin(&attr); 3544 break; 3545 case BPF_OBJ_GET: 3546 err = bpf_obj_get(&attr); 3547 break; 3548 case BPF_PROG_ATTACH: 3549 err = bpf_prog_attach(&attr); 3550 break; 3551 case BPF_PROG_DETACH: 3552 err = bpf_prog_detach(&attr); 3553 break; 3554 case BPF_PROG_QUERY: 3555 err = bpf_prog_query(&attr, uattr); 3556 break; 3557 case BPF_PROG_TEST_RUN: 3558 err = bpf_prog_test_run(&attr, uattr); 3559 break; 3560 case BPF_PROG_GET_NEXT_ID: 3561 err = bpf_obj_get_next_id(&attr, uattr, 3562 &prog_idr, &prog_idr_lock); 3563 break; 3564 case BPF_MAP_GET_NEXT_ID: 3565 err = bpf_obj_get_next_id(&attr, uattr, 3566 &map_idr, &map_idr_lock); 3567 break; 3568 case BPF_BTF_GET_NEXT_ID: 3569 err = bpf_obj_get_next_id(&attr, uattr, 3570 &btf_idr, &btf_idr_lock); 3571 break; 3572 case BPF_PROG_GET_FD_BY_ID: 3573 err = bpf_prog_get_fd_by_id(&attr); 3574 break; 3575 case BPF_MAP_GET_FD_BY_ID: 3576 err = bpf_map_get_fd_by_id(&attr); 3577 break; 3578 case BPF_OBJ_GET_INFO_BY_FD: 3579 err = bpf_obj_get_info_by_fd(&attr, uattr); 3580 break; 3581 case BPF_RAW_TRACEPOINT_OPEN: 3582 err = bpf_raw_tracepoint_open(&attr); 3583 break; 3584 case BPF_BTF_LOAD: 3585 err = bpf_btf_load(&attr); 3586 break; 3587 case BPF_BTF_GET_FD_BY_ID: 3588 err = bpf_btf_get_fd_by_id(&attr); 3589 break; 3590 case BPF_TASK_FD_QUERY: 3591 err = bpf_task_fd_query(&attr, uattr); 3592 break; 3593 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 3594 err = map_lookup_and_delete_elem(&attr); 3595 break; 3596 case BPF_MAP_LOOKUP_BATCH: 3597 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_LOOKUP_BATCH); 3598 break; 3599 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 3600 err = bpf_map_do_batch(&attr, uattr, 3601 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 3602 break; 3603 case BPF_MAP_UPDATE_BATCH: 3604 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_UPDATE_BATCH); 3605 break; 3606 case BPF_MAP_DELETE_BATCH: 3607 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_DELETE_BATCH); 3608 break; 3609 default: 3610 err = -EINVAL; 3611 break; 3612 } 3613 3614 return err; 3615 } 3616