1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf_trace.h> 6 #include <linux/bpf_lirc.h> 7 #include <linux/btf.h> 8 #include <linux/syscalls.h> 9 #include <linux/slab.h> 10 #include <linux/sched/signal.h> 11 #include <linux/vmalloc.h> 12 #include <linux/mmzone.h> 13 #include <linux/anon_inodes.h> 14 #include <linux/fdtable.h> 15 #include <linux/file.h> 16 #include <linux/fs.h> 17 #include <linux/license.h> 18 #include <linux/filter.h> 19 #include <linux/version.h> 20 #include <linux/kernel.h> 21 #include <linux/idr.h> 22 #include <linux/cred.h> 23 #include <linux/timekeeping.h> 24 #include <linux/ctype.h> 25 #include <linux/nospec.h> 26 #include <linux/audit.h> 27 #include <uapi/linux/btf.h> 28 #include <linux/bpf_lsm.h> 29 30 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 31 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 32 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 33 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 34 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 35 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 36 IS_FD_HASH(map)) 37 38 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 39 40 DEFINE_PER_CPU(int, bpf_prog_active); 41 static DEFINE_IDR(prog_idr); 42 static DEFINE_SPINLOCK(prog_idr_lock); 43 static DEFINE_IDR(map_idr); 44 static DEFINE_SPINLOCK(map_idr_lock); 45 46 int sysctl_unprivileged_bpf_disabled __read_mostly; 47 48 static const struct bpf_map_ops * const bpf_map_types[] = { 49 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 50 #define BPF_MAP_TYPE(_id, _ops) \ 51 [_id] = &_ops, 52 #include <linux/bpf_types.h> 53 #undef BPF_PROG_TYPE 54 #undef BPF_MAP_TYPE 55 }; 56 57 /* 58 * If we're handed a bigger struct than we know of, ensure all the unknown bits 59 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 60 * we don't know about yet. 61 * 62 * There is a ToCToU between this function call and the following 63 * copy_from_user() call. However, this is not a concern since this function is 64 * meant to be a future-proofing of bits. 65 */ 66 int bpf_check_uarg_tail_zero(void __user *uaddr, 67 size_t expected_size, 68 size_t actual_size) 69 { 70 unsigned char __user *addr; 71 unsigned char __user *end; 72 unsigned char val; 73 int err; 74 75 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 76 return -E2BIG; 77 78 if (unlikely(!access_ok(uaddr, actual_size))) 79 return -EFAULT; 80 81 if (actual_size <= expected_size) 82 return 0; 83 84 addr = uaddr + expected_size; 85 end = uaddr + actual_size; 86 87 for (; addr < end; addr++) { 88 err = get_user(val, addr); 89 if (err) 90 return err; 91 if (val) 92 return -E2BIG; 93 } 94 95 return 0; 96 } 97 98 const struct bpf_map_ops bpf_map_offload_ops = { 99 .map_alloc = bpf_map_offload_map_alloc, 100 .map_free = bpf_map_offload_map_free, 101 .map_check_btf = map_check_no_btf, 102 }; 103 104 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) 105 { 106 const struct bpf_map_ops *ops; 107 u32 type = attr->map_type; 108 struct bpf_map *map; 109 int err; 110 111 if (type >= ARRAY_SIZE(bpf_map_types)) 112 return ERR_PTR(-EINVAL); 113 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types)); 114 ops = bpf_map_types[type]; 115 if (!ops) 116 return ERR_PTR(-EINVAL); 117 118 if (ops->map_alloc_check) { 119 err = ops->map_alloc_check(attr); 120 if (err) 121 return ERR_PTR(err); 122 } 123 if (attr->map_ifindex) 124 ops = &bpf_map_offload_ops; 125 map = ops->map_alloc(attr); 126 if (IS_ERR(map)) 127 return map; 128 map->ops = ops; 129 map->map_type = type; 130 return map; 131 } 132 133 static u32 bpf_map_value_size(struct bpf_map *map) 134 { 135 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 136 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 137 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 138 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 139 return round_up(map->value_size, 8) * num_possible_cpus(); 140 else if (IS_FD_MAP(map)) 141 return sizeof(u32); 142 else 143 return map->value_size; 144 } 145 146 static void maybe_wait_bpf_programs(struct bpf_map *map) 147 { 148 /* Wait for any running BPF programs to complete so that 149 * userspace, when we return to it, knows that all programs 150 * that could be running use the new map value. 151 */ 152 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 153 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 154 synchronize_rcu(); 155 } 156 157 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, 158 void *value, __u64 flags) 159 { 160 int err; 161 162 /* Need to create a kthread, thus must support schedule */ 163 if (bpf_map_is_dev_bound(map)) { 164 return bpf_map_offload_update_elem(map, key, value, flags); 165 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 166 map->map_type == BPF_MAP_TYPE_SOCKHASH || 167 map->map_type == BPF_MAP_TYPE_SOCKMAP || 168 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 169 return map->ops->map_update_elem(map, key, value, flags); 170 } else if (IS_FD_PROG_ARRAY(map)) { 171 return bpf_fd_array_map_update_elem(map, f.file, key, value, 172 flags); 173 } 174 175 bpf_disable_instrumentation(); 176 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 177 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 178 err = bpf_percpu_hash_update(map, key, value, flags); 179 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 180 err = bpf_percpu_array_update(map, key, value, flags); 181 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 182 err = bpf_percpu_cgroup_storage_update(map, key, value, 183 flags); 184 } else if (IS_FD_ARRAY(map)) { 185 rcu_read_lock(); 186 err = bpf_fd_array_map_update_elem(map, f.file, key, value, 187 flags); 188 rcu_read_unlock(); 189 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 190 rcu_read_lock(); 191 err = bpf_fd_htab_map_update_elem(map, f.file, key, value, 192 flags); 193 rcu_read_unlock(); 194 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 195 /* rcu_read_lock() is not needed */ 196 err = bpf_fd_reuseport_array_update_elem(map, key, value, 197 flags); 198 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 199 map->map_type == BPF_MAP_TYPE_STACK) { 200 err = map->ops->map_push_elem(map, value, flags); 201 } else { 202 rcu_read_lock(); 203 err = map->ops->map_update_elem(map, key, value, flags); 204 rcu_read_unlock(); 205 } 206 bpf_enable_instrumentation(); 207 maybe_wait_bpf_programs(map); 208 209 return err; 210 } 211 212 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 213 __u64 flags) 214 { 215 void *ptr; 216 int err; 217 218 if (bpf_map_is_dev_bound(map)) 219 return bpf_map_offload_lookup_elem(map, key, value); 220 221 bpf_disable_instrumentation(); 222 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 223 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 224 err = bpf_percpu_hash_copy(map, key, value); 225 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 226 err = bpf_percpu_array_copy(map, key, value); 227 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 228 err = bpf_percpu_cgroup_storage_copy(map, key, value); 229 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 230 err = bpf_stackmap_copy(map, key, value); 231 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 232 err = bpf_fd_array_map_lookup_elem(map, key, value); 233 } else if (IS_FD_HASH(map)) { 234 err = bpf_fd_htab_map_lookup_elem(map, key, value); 235 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 236 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 237 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 238 map->map_type == BPF_MAP_TYPE_STACK) { 239 err = map->ops->map_peek_elem(map, value); 240 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 241 /* struct_ops map requires directly updating "value" */ 242 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 243 } else { 244 rcu_read_lock(); 245 if (map->ops->map_lookup_elem_sys_only) 246 ptr = map->ops->map_lookup_elem_sys_only(map, key); 247 else 248 ptr = map->ops->map_lookup_elem(map, key); 249 if (IS_ERR(ptr)) { 250 err = PTR_ERR(ptr); 251 } else if (!ptr) { 252 err = -ENOENT; 253 } else { 254 err = 0; 255 if (flags & BPF_F_LOCK) 256 /* lock 'ptr' and copy everything but lock */ 257 copy_map_value_locked(map, value, ptr, true); 258 else 259 copy_map_value(map, value, ptr); 260 /* mask lock, since value wasn't zero inited */ 261 check_and_init_map_lock(map, value); 262 } 263 rcu_read_unlock(); 264 } 265 266 bpf_enable_instrumentation(); 267 maybe_wait_bpf_programs(map); 268 269 return err; 270 } 271 272 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 273 { 274 /* We really just want to fail instead of triggering OOM killer 275 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 276 * which is used for lower order allocation requests. 277 * 278 * It has been observed that higher order allocation requests done by 279 * vmalloc with __GFP_NORETRY being set might fail due to not trying 280 * to reclaim memory from the page cache, thus we set 281 * __GFP_RETRY_MAYFAIL to avoid such situations. 282 */ 283 284 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; 285 void *area; 286 287 if (size >= SIZE_MAX) 288 return NULL; 289 290 /* kmalloc()'ed memory can't be mmap()'ed */ 291 if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 292 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, 293 numa_node); 294 if (area != NULL) 295 return area; 296 } 297 if (mmapable) { 298 BUG_ON(!PAGE_ALIGNED(size)); 299 return vmalloc_user_node_flags(size, numa_node, GFP_KERNEL | 300 __GFP_RETRY_MAYFAIL | flags); 301 } 302 return __vmalloc_node_flags_caller(size, numa_node, 303 GFP_KERNEL | __GFP_RETRY_MAYFAIL | 304 flags, __builtin_return_address(0)); 305 } 306 307 void *bpf_map_area_alloc(u64 size, int numa_node) 308 { 309 return __bpf_map_area_alloc(size, numa_node, false); 310 } 311 312 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 313 { 314 return __bpf_map_area_alloc(size, numa_node, true); 315 } 316 317 void bpf_map_area_free(void *area) 318 { 319 kvfree(area); 320 } 321 322 static u32 bpf_map_flags_retain_permanent(u32 flags) 323 { 324 /* Some map creation flags are not tied to the map object but 325 * rather to the map fd instead, so they have no meaning upon 326 * map object inspection since multiple file descriptors with 327 * different (access) properties can exist here. Thus, given 328 * this has zero meaning for the map itself, lets clear these 329 * from here. 330 */ 331 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 332 } 333 334 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 335 { 336 map->map_type = attr->map_type; 337 map->key_size = attr->key_size; 338 map->value_size = attr->value_size; 339 map->max_entries = attr->max_entries; 340 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 341 map->numa_node = bpf_map_attr_numa_node(attr); 342 } 343 344 static int bpf_charge_memlock(struct user_struct *user, u32 pages) 345 { 346 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 347 348 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) { 349 atomic_long_sub(pages, &user->locked_vm); 350 return -EPERM; 351 } 352 return 0; 353 } 354 355 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages) 356 { 357 if (user) 358 atomic_long_sub(pages, &user->locked_vm); 359 } 360 361 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size) 362 { 363 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT; 364 struct user_struct *user; 365 int ret; 366 367 if (size >= U32_MAX - PAGE_SIZE) 368 return -E2BIG; 369 370 user = get_current_user(); 371 ret = bpf_charge_memlock(user, pages); 372 if (ret) { 373 free_uid(user); 374 return ret; 375 } 376 377 mem->pages = pages; 378 mem->user = user; 379 380 return 0; 381 } 382 383 void bpf_map_charge_finish(struct bpf_map_memory *mem) 384 { 385 bpf_uncharge_memlock(mem->user, mem->pages); 386 free_uid(mem->user); 387 } 388 389 void bpf_map_charge_move(struct bpf_map_memory *dst, 390 struct bpf_map_memory *src) 391 { 392 *dst = *src; 393 394 /* Make sure src will not be used for the redundant uncharging. */ 395 memset(src, 0, sizeof(struct bpf_map_memory)); 396 } 397 398 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages) 399 { 400 int ret; 401 402 ret = bpf_charge_memlock(map->memory.user, pages); 403 if (ret) 404 return ret; 405 map->memory.pages += pages; 406 return ret; 407 } 408 409 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages) 410 { 411 bpf_uncharge_memlock(map->memory.user, pages); 412 map->memory.pages -= pages; 413 } 414 415 static int bpf_map_alloc_id(struct bpf_map *map) 416 { 417 int id; 418 419 idr_preload(GFP_KERNEL); 420 spin_lock_bh(&map_idr_lock); 421 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 422 if (id > 0) 423 map->id = id; 424 spin_unlock_bh(&map_idr_lock); 425 idr_preload_end(); 426 427 if (WARN_ON_ONCE(!id)) 428 return -ENOSPC; 429 430 return id > 0 ? 0 : id; 431 } 432 433 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) 434 { 435 unsigned long flags; 436 437 /* Offloaded maps are removed from the IDR store when their device 438 * disappears - even if someone holds an fd to them they are unusable, 439 * the memory is gone, all ops will fail; they are simply waiting for 440 * refcnt to drop to be freed. 441 */ 442 if (!map->id) 443 return; 444 445 if (do_idr_lock) 446 spin_lock_irqsave(&map_idr_lock, flags); 447 else 448 __acquire(&map_idr_lock); 449 450 idr_remove(&map_idr, map->id); 451 map->id = 0; 452 453 if (do_idr_lock) 454 spin_unlock_irqrestore(&map_idr_lock, flags); 455 else 456 __release(&map_idr_lock); 457 } 458 459 /* called from workqueue */ 460 static void bpf_map_free_deferred(struct work_struct *work) 461 { 462 struct bpf_map *map = container_of(work, struct bpf_map, work); 463 struct bpf_map_memory mem; 464 465 bpf_map_charge_move(&mem, &map->memory); 466 security_bpf_map_free(map); 467 /* implementation dependent freeing */ 468 map->ops->map_free(map); 469 bpf_map_charge_finish(&mem); 470 } 471 472 static void bpf_map_put_uref(struct bpf_map *map) 473 { 474 if (atomic64_dec_and_test(&map->usercnt)) { 475 if (map->ops->map_release_uref) 476 map->ops->map_release_uref(map); 477 } 478 } 479 480 /* decrement map refcnt and schedule it for freeing via workqueue 481 * (unrelying map implementation ops->map_free() might sleep) 482 */ 483 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) 484 { 485 if (atomic64_dec_and_test(&map->refcnt)) { 486 /* bpf_map_free_id() must be called first */ 487 bpf_map_free_id(map, do_idr_lock); 488 btf_put(map->btf); 489 INIT_WORK(&map->work, bpf_map_free_deferred); 490 schedule_work(&map->work); 491 } 492 } 493 494 void bpf_map_put(struct bpf_map *map) 495 { 496 __bpf_map_put(map, true); 497 } 498 EXPORT_SYMBOL_GPL(bpf_map_put); 499 500 void bpf_map_put_with_uref(struct bpf_map *map) 501 { 502 bpf_map_put_uref(map); 503 bpf_map_put(map); 504 } 505 506 static int bpf_map_release(struct inode *inode, struct file *filp) 507 { 508 struct bpf_map *map = filp->private_data; 509 510 if (map->ops->map_release) 511 map->ops->map_release(map, filp); 512 513 bpf_map_put_with_uref(map); 514 return 0; 515 } 516 517 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 518 { 519 fmode_t mode = f.file->f_mode; 520 521 /* Our file permissions may have been overridden by global 522 * map permissions facing syscall side. 523 */ 524 if (READ_ONCE(map->frozen)) 525 mode &= ~FMODE_CAN_WRITE; 526 return mode; 527 } 528 529 #ifdef CONFIG_PROC_FS 530 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 531 { 532 const struct bpf_map *map = filp->private_data; 533 const struct bpf_array *array; 534 u32 type = 0, jited = 0; 535 536 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { 537 array = container_of(map, struct bpf_array, map); 538 type = array->aux->type; 539 jited = array->aux->jited; 540 } 541 542 seq_printf(m, 543 "map_type:\t%u\n" 544 "key_size:\t%u\n" 545 "value_size:\t%u\n" 546 "max_entries:\t%u\n" 547 "map_flags:\t%#x\n" 548 "memlock:\t%llu\n" 549 "map_id:\t%u\n" 550 "frozen:\t%u\n", 551 map->map_type, 552 map->key_size, 553 map->value_size, 554 map->max_entries, 555 map->map_flags, 556 map->memory.pages * 1ULL << PAGE_SHIFT, 557 map->id, 558 READ_ONCE(map->frozen)); 559 if (type) { 560 seq_printf(m, "owner_prog_type:\t%u\n", type); 561 seq_printf(m, "owner_jited:\t%u\n", jited); 562 } 563 } 564 #endif 565 566 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 567 loff_t *ppos) 568 { 569 /* We need this handler such that alloc_file() enables 570 * f_mode with FMODE_CAN_READ. 571 */ 572 return -EINVAL; 573 } 574 575 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 576 size_t siz, loff_t *ppos) 577 { 578 /* We need this handler such that alloc_file() enables 579 * f_mode with FMODE_CAN_WRITE. 580 */ 581 return -EINVAL; 582 } 583 584 /* called for any extra memory-mapped regions (except initial) */ 585 static void bpf_map_mmap_open(struct vm_area_struct *vma) 586 { 587 struct bpf_map *map = vma->vm_file->private_data; 588 589 if (vma->vm_flags & VM_MAYWRITE) { 590 mutex_lock(&map->freeze_mutex); 591 map->writecnt++; 592 mutex_unlock(&map->freeze_mutex); 593 } 594 } 595 596 /* called for all unmapped memory region (including initial) */ 597 static void bpf_map_mmap_close(struct vm_area_struct *vma) 598 { 599 struct bpf_map *map = vma->vm_file->private_data; 600 601 if (vma->vm_flags & VM_MAYWRITE) { 602 mutex_lock(&map->freeze_mutex); 603 map->writecnt--; 604 mutex_unlock(&map->freeze_mutex); 605 } 606 } 607 608 static const struct vm_operations_struct bpf_map_default_vmops = { 609 .open = bpf_map_mmap_open, 610 .close = bpf_map_mmap_close, 611 }; 612 613 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 614 { 615 struct bpf_map *map = filp->private_data; 616 int err; 617 618 if (!map->ops->map_mmap || map_value_has_spin_lock(map)) 619 return -ENOTSUPP; 620 621 if (!(vma->vm_flags & VM_SHARED)) 622 return -EINVAL; 623 624 mutex_lock(&map->freeze_mutex); 625 626 if ((vma->vm_flags & VM_WRITE) && map->frozen) { 627 err = -EPERM; 628 goto out; 629 } 630 631 /* set default open/close callbacks */ 632 vma->vm_ops = &bpf_map_default_vmops; 633 vma->vm_private_data = map; 634 vma->vm_flags &= ~VM_MAYEXEC; 635 if (!(vma->vm_flags & VM_WRITE)) 636 /* disallow re-mapping with PROT_WRITE */ 637 vma->vm_flags &= ~VM_MAYWRITE; 638 639 err = map->ops->map_mmap(map, vma); 640 if (err) 641 goto out; 642 643 if (vma->vm_flags & VM_MAYWRITE) 644 map->writecnt++; 645 out: 646 mutex_unlock(&map->freeze_mutex); 647 return err; 648 } 649 650 const struct file_operations bpf_map_fops = { 651 #ifdef CONFIG_PROC_FS 652 .show_fdinfo = bpf_map_show_fdinfo, 653 #endif 654 .release = bpf_map_release, 655 .read = bpf_dummy_read, 656 .write = bpf_dummy_write, 657 .mmap = bpf_map_mmap, 658 }; 659 660 int bpf_map_new_fd(struct bpf_map *map, int flags) 661 { 662 int ret; 663 664 ret = security_bpf_map(map, OPEN_FMODE(flags)); 665 if (ret < 0) 666 return ret; 667 668 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 669 flags | O_CLOEXEC); 670 } 671 672 int bpf_get_file_flag(int flags) 673 { 674 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 675 return -EINVAL; 676 if (flags & BPF_F_RDONLY) 677 return O_RDONLY; 678 if (flags & BPF_F_WRONLY) 679 return O_WRONLY; 680 return O_RDWR; 681 } 682 683 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 684 #define CHECK_ATTR(CMD) \ 685 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 686 sizeof(attr->CMD##_LAST_FIELD), 0, \ 687 sizeof(*attr) - \ 688 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 689 sizeof(attr->CMD##_LAST_FIELD)) != NULL 690 691 /* dst and src must have at least "size" number of bytes. 692 * Return strlen on success and < 0 on error. 693 */ 694 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 695 { 696 const char *end = src + size; 697 const char *orig_src = src; 698 699 memset(dst, 0, size); 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 "size" number of bytes */ 709 if (src == end) 710 return -EINVAL; 711 712 return src - orig_src; 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 sizeof(attr->map_name)); 808 if (err < 0) 809 goto free_map; 810 811 atomic64_set(&map->refcnt, 1); 812 atomic64_set(&map->usercnt, 1); 813 mutex_init(&map->freeze_mutex); 814 815 map->spin_lock_off = -EINVAL; 816 if (attr->btf_key_type_id || attr->btf_value_type_id || 817 /* Even the map's value is a kernel's struct, 818 * the bpf_prog.o must have BTF to begin with 819 * to figure out the corresponding kernel's 820 * counter part. Thus, attr->btf_fd has 821 * to be valid also. 822 */ 823 attr->btf_vmlinux_value_type_id) { 824 struct btf *btf; 825 826 btf = btf_get_by_fd(attr->btf_fd); 827 if (IS_ERR(btf)) { 828 err = PTR_ERR(btf); 829 goto free_map; 830 } 831 map->btf = btf; 832 833 if (attr->btf_value_type_id) { 834 err = map_check_btf(map, btf, attr->btf_key_type_id, 835 attr->btf_value_type_id); 836 if (err) 837 goto free_map; 838 } 839 840 map->btf_key_type_id = attr->btf_key_type_id; 841 map->btf_value_type_id = attr->btf_value_type_id; 842 map->btf_vmlinux_value_type_id = 843 attr->btf_vmlinux_value_type_id; 844 } 845 846 err = security_bpf_map_alloc(map); 847 if (err) 848 goto free_map; 849 850 err = bpf_map_alloc_id(map); 851 if (err) 852 goto free_map_sec; 853 854 err = bpf_map_new_fd(map, f_flags); 855 if (err < 0) { 856 /* failed to allocate fd. 857 * bpf_map_put_with_uref() is needed because the above 858 * bpf_map_alloc_id() has published the map 859 * to the userspace and the userspace may 860 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 861 */ 862 bpf_map_put_with_uref(map); 863 return err; 864 } 865 866 return err; 867 868 free_map_sec: 869 security_bpf_map_free(map); 870 free_map: 871 btf_put(map->btf); 872 bpf_map_charge_move(&mem, &map->memory); 873 map->ops->map_free(map); 874 bpf_map_charge_finish(&mem); 875 return err; 876 } 877 878 /* if error is returned, fd is released. 879 * On success caller should complete fd access with matching fdput() 880 */ 881 struct bpf_map *__bpf_map_get(struct fd f) 882 { 883 if (!f.file) 884 return ERR_PTR(-EBADF); 885 if (f.file->f_op != &bpf_map_fops) { 886 fdput(f); 887 return ERR_PTR(-EINVAL); 888 } 889 890 return f.file->private_data; 891 } 892 893 void bpf_map_inc(struct bpf_map *map) 894 { 895 atomic64_inc(&map->refcnt); 896 } 897 EXPORT_SYMBOL_GPL(bpf_map_inc); 898 899 void bpf_map_inc_with_uref(struct bpf_map *map) 900 { 901 atomic64_inc(&map->refcnt); 902 atomic64_inc(&map->usercnt); 903 } 904 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 905 906 struct bpf_map *bpf_map_get(u32 ufd) 907 { 908 struct fd f = fdget(ufd); 909 struct bpf_map *map; 910 911 map = __bpf_map_get(f); 912 if (IS_ERR(map)) 913 return map; 914 915 bpf_map_inc(map); 916 fdput(f); 917 918 return map; 919 } 920 921 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 922 { 923 struct fd f = fdget(ufd); 924 struct bpf_map *map; 925 926 map = __bpf_map_get(f); 927 if (IS_ERR(map)) 928 return map; 929 930 bpf_map_inc_with_uref(map); 931 fdput(f); 932 933 return map; 934 } 935 936 /* map_idr_lock should have been held */ 937 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 938 { 939 int refold; 940 941 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 942 if (!refold) 943 return ERR_PTR(-ENOENT); 944 if (uref) 945 atomic64_inc(&map->usercnt); 946 947 return map; 948 } 949 950 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 951 { 952 spin_lock_bh(&map_idr_lock); 953 map = __bpf_map_inc_not_zero(map, false); 954 spin_unlock_bh(&map_idr_lock); 955 956 return map; 957 } 958 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 959 960 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 961 { 962 return -ENOTSUPP; 963 } 964 965 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 966 { 967 if (key_size) 968 return memdup_user(ukey, key_size); 969 970 if (ukey) 971 return ERR_PTR(-EINVAL); 972 973 return NULL; 974 } 975 976 /* last field in 'union bpf_attr' used by this command */ 977 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 978 979 static int map_lookup_elem(union bpf_attr *attr) 980 { 981 void __user *ukey = u64_to_user_ptr(attr->key); 982 void __user *uvalue = u64_to_user_ptr(attr->value); 983 int ufd = attr->map_fd; 984 struct bpf_map *map; 985 void *key, *value; 986 u32 value_size; 987 struct fd f; 988 int err; 989 990 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 991 return -EINVAL; 992 993 if (attr->flags & ~BPF_F_LOCK) 994 return -EINVAL; 995 996 f = fdget(ufd); 997 map = __bpf_map_get(f); 998 if (IS_ERR(map)) 999 return PTR_ERR(map); 1000 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1001 err = -EPERM; 1002 goto err_put; 1003 } 1004 1005 if ((attr->flags & BPF_F_LOCK) && 1006 !map_value_has_spin_lock(map)) { 1007 err = -EINVAL; 1008 goto err_put; 1009 } 1010 1011 key = __bpf_copy_key(ukey, map->key_size); 1012 if (IS_ERR(key)) { 1013 err = PTR_ERR(key); 1014 goto err_put; 1015 } 1016 1017 value_size = bpf_map_value_size(map); 1018 1019 err = -ENOMEM; 1020 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1021 if (!value) 1022 goto free_key; 1023 1024 err = bpf_map_copy_value(map, key, value, attr->flags); 1025 if (err) 1026 goto free_value; 1027 1028 err = -EFAULT; 1029 if (copy_to_user(uvalue, value, value_size) != 0) 1030 goto free_value; 1031 1032 err = 0; 1033 1034 free_value: 1035 kfree(value); 1036 free_key: 1037 kfree(key); 1038 err_put: 1039 fdput(f); 1040 return err; 1041 } 1042 1043 1044 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1045 1046 static int map_update_elem(union bpf_attr *attr) 1047 { 1048 void __user *ukey = u64_to_user_ptr(attr->key); 1049 void __user *uvalue = u64_to_user_ptr(attr->value); 1050 int ufd = attr->map_fd; 1051 struct bpf_map *map; 1052 void *key, *value; 1053 u32 value_size; 1054 struct fd f; 1055 int err; 1056 1057 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1058 return -EINVAL; 1059 1060 f = fdget(ufd); 1061 map = __bpf_map_get(f); 1062 if (IS_ERR(map)) 1063 return PTR_ERR(map); 1064 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1065 err = -EPERM; 1066 goto err_put; 1067 } 1068 1069 if ((attr->flags & BPF_F_LOCK) && 1070 !map_value_has_spin_lock(map)) { 1071 err = -EINVAL; 1072 goto err_put; 1073 } 1074 1075 key = __bpf_copy_key(ukey, map->key_size); 1076 if (IS_ERR(key)) { 1077 err = PTR_ERR(key); 1078 goto err_put; 1079 } 1080 1081 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 1082 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 1083 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 1084 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 1085 value_size = round_up(map->value_size, 8) * num_possible_cpus(); 1086 else 1087 value_size = map->value_size; 1088 1089 err = -ENOMEM; 1090 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1091 if (!value) 1092 goto free_key; 1093 1094 err = -EFAULT; 1095 if (copy_from_user(value, uvalue, value_size) != 0) 1096 goto free_value; 1097 1098 err = bpf_map_update_value(map, f, key, value, attr->flags); 1099 1100 free_value: 1101 kfree(value); 1102 free_key: 1103 kfree(key); 1104 err_put: 1105 fdput(f); 1106 return err; 1107 } 1108 1109 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1110 1111 static int map_delete_elem(union bpf_attr *attr) 1112 { 1113 void __user *ukey = u64_to_user_ptr(attr->key); 1114 int ufd = attr->map_fd; 1115 struct bpf_map *map; 1116 struct fd f; 1117 void *key; 1118 int err; 1119 1120 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1121 return -EINVAL; 1122 1123 f = fdget(ufd); 1124 map = __bpf_map_get(f); 1125 if (IS_ERR(map)) 1126 return PTR_ERR(map); 1127 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1128 err = -EPERM; 1129 goto err_put; 1130 } 1131 1132 key = __bpf_copy_key(ukey, map->key_size); 1133 if (IS_ERR(key)) { 1134 err = PTR_ERR(key); 1135 goto err_put; 1136 } 1137 1138 if (bpf_map_is_dev_bound(map)) { 1139 err = bpf_map_offload_delete_elem(map, key); 1140 goto out; 1141 } else if (IS_FD_PROG_ARRAY(map) || 1142 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1143 /* These maps require sleepable context */ 1144 err = map->ops->map_delete_elem(map, key); 1145 goto out; 1146 } 1147 1148 bpf_disable_instrumentation(); 1149 rcu_read_lock(); 1150 err = map->ops->map_delete_elem(map, key); 1151 rcu_read_unlock(); 1152 bpf_enable_instrumentation(); 1153 maybe_wait_bpf_programs(map); 1154 out: 1155 kfree(key); 1156 err_put: 1157 fdput(f); 1158 return err; 1159 } 1160 1161 /* last field in 'union bpf_attr' used by this command */ 1162 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1163 1164 static int map_get_next_key(union bpf_attr *attr) 1165 { 1166 void __user *ukey = u64_to_user_ptr(attr->key); 1167 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1168 int ufd = attr->map_fd; 1169 struct bpf_map *map; 1170 void *key, *next_key; 1171 struct fd f; 1172 int err; 1173 1174 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1175 return -EINVAL; 1176 1177 f = fdget(ufd); 1178 map = __bpf_map_get(f); 1179 if (IS_ERR(map)) 1180 return PTR_ERR(map); 1181 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1182 err = -EPERM; 1183 goto err_put; 1184 } 1185 1186 if (ukey) { 1187 key = __bpf_copy_key(ukey, map->key_size); 1188 if (IS_ERR(key)) { 1189 err = PTR_ERR(key); 1190 goto err_put; 1191 } 1192 } else { 1193 key = NULL; 1194 } 1195 1196 err = -ENOMEM; 1197 next_key = kmalloc(map->key_size, GFP_USER); 1198 if (!next_key) 1199 goto free_key; 1200 1201 if (bpf_map_is_dev_bound(map)) { 1202 err = bpf_map_offload_get_next_key(map, key, next_key); 1203 goto out; 1204 } 1205 1206 rcu_read_lock(); 1207 err = map->ops->map_get_next_key(map, key, next_key); 1208 rcu_read_unlock(); 1209 out: 1210 if (err) 1211 goto free_next_key; 1212 1213 err = -EFAULT; 1214 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1215 goto free_next_key; 1216 1217 err = 0; 1218 1219 free_next_key: 1220 kfree(next_key); 1221 free_key: 1222 kfree(key); 1223 err_put: 1224 fdput(f); 1225 return err; 1226 } 1227 1228 int generic_map_delete_batch(struct bpf_map *map, 1229 const union bpf_attr *attr, 1230 union bpf_attr __user *uattr) 1231 { 1232 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1233 u32 cp, max_count; 1234 int err = 0; 1235 void *key; 1236 1237 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1238 return -EINVAL; 1239 1240 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1241 !map_value_has_spin_lock(map)) { 1242 return -EINVAL; 1243 } 1244 1245 max_count = attr->batch.count; 1246 if (!max_count) 1247 return 0; 1248 1249 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1250 if (!key) 1251 return -ENOMEM; 1252 1253 for (cp = 0; cp < max_count; cp++) { 1254 err = -EFAULT; 1255 if (copy_from_user(key, keys + cp * map->key_size, 1256 map->key_size)) 1257 break; 1258 1259 if (bpf_map_is_dev_bound(map)) { 1260 err = bpf_map_offload_delete_elem(map, key); 1261 break; 1262 } 1263 1264 bpf_disable_instrumentation(); 1265 rcu_read_lock(); 1266 err = map->ops->map_delete_elem(map, key); 1267 rcu_read_unlock(); 1268 bpf_enable_instrumentation(); 1269 maybe_wait_bpf_programs(map); 1270 if (err) 1271 break; 1272 } 1273 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1274 err = -EFAULT; 1275 1276 kfree(key); 1277 return err; 1278 } 1279 1280 int generic_map_update_batch(struct bpf_map *map, 1281 const union bpf_attr *attr, 1282 union bpf_attr __user *uattr) 1283 { 1284 void __user *values = u64_to_user_ptr(attr->batch.values); 1285 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1286 u32 value_size, cp, max_count; 1287 int ufd = attr->map_fd; 1288 void *key, *value; 1289 struct fd f; 1290 int err = 0; 1291 1292 f = fdget(ufd); 1293 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1294 return -EINVAL; 1295 1296 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1297 !map_value_has_spin_lock(map)) { 1298 return -EINVAL; 1299 } 1300 1301 value_size = bpf_map_value_size(map); 1302 1303 max_count = attr->batch.count; 1304 if (!max_count) 1305 return 0; 1306 1307 key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1308 if (!key) 1309 return -ENOMEM; 1310 1311 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1312 if (!value) { 1313 kfree(key); 1314 return -ENOMEM; 1315 } 1316 1317 for (cp = 0; cp < max_count; cp++) { 1318 err = -EFAULT; 1319 if (copy_from_user(key, keys + cp * map->key_size, 1320 map->key_size) || 1321 copy_from_user(value, values + cp * value_size, value_size)) 1322 break; 1323 1324 err = bpf_map_update_value(map, f, key, value, 1325 attr->batch.elem_flags); 1326 1327 if (err) 1328 break; 1329 } 1330 1331 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1332 err = -EFAULT; 1333 1334 kfree(value); 1335 kfree(key); 1336 return err; 1337 } 1338 1339 #define MAP_LOOKUP_RETRIES 3 1340 1341 int generic_map_lookup_batch(struct bpf_map *map, 1342 const union bpf_attr *attr, 1343 union bpf_attr __user *uattr) 1344 { 1345 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1346 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1347 void __user *values = u64_to_user_ptr(attr->batch.values); 1348 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1349 void *buf, *buf_prevkey, *prev_key, *key, *value; 1350 int err, retry = MAP_LOOKUP_RETRIES; 1351 u32 value_size, cp, max_count; 1352 1353 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1354 return -EINVAL; 1355 1356 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1357 !map_value_has_spin_lock(map)) 1358 return -EINVAL; 1359 1360 value_size = bpf_map_value_size(map); 1361 1362 max_count = attr->batch.count; 1363 if (!max_count) 1364 return 0; 1365 1366 if (put_user(0, &uattr->batch.count)) 1367 return -EFAULT; 1368 1369 buf_prevkey = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1370 if (!buf_prevkey) 1371 return -ENOMEM; 1372 1373 buf = kmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1374 if (!buf) { 1375 kvfree(buf_prevkey); 1376 return -ENOMEM; 1377 } 1378 1379 err = -EFAULT; 1380 prev_key = NULL; 1381 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1382 goto free_buf; 1383 key = buf; 1384 value = key + map->key_size; 1385 if (ubatch) 1386 prev_key = buf_prevkey; 1387 1388 for (cp = 0; cp < max_count;) { 1389 rcu_read_lock(); 1390 err = map->ops->map_get_next_key(map, prev_key, key); 1391 rcu_read_unlock(); 1392 if (err) 1393 break; 1394 err = bpf_map_copy_value(map, key, value, 1395 attr->batch.elem_flags); 1396 1397 if (err == -ENOENT) { 1398 if (retry) { 1399 retry--; 1400 continue; 1401 } 1402 err = -EINTR; 1403 break; 1404 } 1405 1406 if (err) 1407 goto free_buf; 1408 1409 if (copy_to_user(keys + cp * map->key_size, key, 1410 map->key_size)) { 1411 err = -EFAULT; 1412 goto free_buf; 1413 } 1414 if (copy_to_user(values + cp * value_size, value, value_size)) { 1415 err = -EFAULT; 1416 goto free_buf; 1417 } 1418 1419 if (!prev_key) 1420 prev_key = buf_prevkey; 1421 1422 swap(prev_key, key); 1423 retry = MAP_LOOKUP_RETRIES; 1424 cp++; 1425 } 1426 1427 if (err == -EFAULT) 1428 goto free_buf; 1429 1430 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1431 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1432 err = -EFAULT; 1433 1434 free_buf: 1435 kfree(buf_prevkey); 1436 kfree(buf); 1437 return err; 1438 } 1439 1440 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value 1441 1442 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1443 { 1444 void __user *ukey = u64_to_user_ptr(attr->key); 1445 void __user *uvalue = u64_to_user_ptr(attr->value); 1446 int ufd = attr->map_fd; 1447 struct bpf_map *map; 1448 void *key, *value; 1449 u32 value_size; 1450 struct fd f; 1451 int err; 1452 1453 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1454 return -EINVAL; 1455 1456 f = fdget(ufd); 1457 map = __bpf_map_get(f); 1458 if (IS_ERR(map)) 1459 return PTR_ERR(map); 1460 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1461 err = -EPERM; 1462 goto err_put; 1463 } 1464 1465 key = __bpf_copy_key(ukey, map->key_size); 1466 if (IS_ERR(key)) { 1467 err = PTR_ERR(key); 1468 goto err_put; 1469 } 1470 1471 value_size = map->value_size; 1472 1473 err = -ENOMEM; 1474 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); 1475 if (!value) 1476 goto free_key; 1477 1478 if (map->map_type == BPF_MAP_TYPE_QUEUE || 1479 map->map_type == BPF_MAP_TYPE_STACK) { 1480 err = map->ops->map_pop_elem(map, value); 1481 } else { 1482 err = -ENOTSUPP; 1483 } 1484 1485 if (err) 1486 goto free_value; 1487 1488 if (copy_to_user(uvalue, value, value_size) != 0) 1489 goto free_value; 1490 1491 err = 0; 1492 1493 free_value: 1494 kfree(value); 1495 free_key: 1496 kfree(key); 1497 err_put: 1498 fdput(f); 1499 return err; 1500 } 1501 1502 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 1503 1504 static int map_freeze(const union bpf_attr *attr) 1505 { 1506 int err = 0, ufd = attr->map_fd; 1507 struct bpf_map *map; 1508 struct fd f; 1509 1510 if (CHECK_ATTR(BPF_MAP_FREEZE)) 1511 return -EINVAL; 1512 1513 f = fdget(ufd); 1514 map = __bpf_map_get(f); 1515 if (IS_ERR(map)) 1516 return PTR_ERR(map); 1517 1518 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1519 fdput(f); 1520 return -ENOTSUPP; 1521 } 1522 1523 mutex_lock(&map->freeze_mutex); 1524 1525 if (map->writecnt) { 1526 err = -EBUSY; 1527 goto err_put; 1528 } 1529 if (READ_ONCE(map->frozen)) { 1530 err = -EBUSY; 1531 goto err_put; 1532 } 1533 if (!capable(CAP_SYS_ADMIN)) { 1534 err = -EPERM; 1535 goto err_put; 1536 } 1537 1538 WRITE_ONCE(map->frozen, true); 1539 err_put: 1540 mutex_unlock(&map->freeze_mutex); 1541 fdput(f); 1542 return err; 1543 } 1544 1545 static const struct bpf_prog_ops * const bpf_prog_types[] = { 1546 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 1547 [_id] = & _name ## _prog_ops, 1548 #define BPF_MAP_TYPE(_id, _ops) 1549 #include <linux/bpf_types.h> 1550 #undef BPF_PROG_TYPE 1551 #undef BPF_MAP_TYPE 1552 }; 1553 1554 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 1555 { 1556 const struct bpf_prog_ops *ops; 1557 1558 if (type >= ARRAY_SIZE(bpf_prog_types)) 1559 return -EINVAL; 1560 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 1561 ops = bpf_prog_types[type]; 1562 if (!ops) 1563 return -EINVAL; 1564 1565 if (!bpf_prog_is_dev_bound(prog->aux)) 1566 prog->aux->ops = ops; 1567 else 1568 prog->aux->ops = &bpf_offload_prog_ops; 1569 prog->type = type; 1570 return 0; 1571 } 1572 1573 enum bpf_audit { 1574 BPF_AUDIT_LOAD, 1575 BPF_AUDIT_UNLOAD, 1576 BPF_AUDIT_MAX, 1577 }; 1578 1579 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 1580 [BPF_AUDIT_LOAD] = "LOAD", 1581 [BPF_AUDIT_UNLOAD] = "UNLOAD", 1582 }; 1583 1584 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 1585 { 1586 struct audit_context *ctx = NULL; 1587 struct audit_buffer *ab; 1588 1589 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 1590 return; 1591 if (audit_enabled == AUDIT_OFF) 1592 return; 1593 if (op == BPF_AUDIT_LOAD) 1594 ctx = audit_context(); 1595 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 1596 if (unlikely(!ab)) 1597 return; 1598 audit_log_format(ab, "prog-id=%u op=%s", 1599 prog->aux->id, bpf_audit_str[op]); 1600 audit_log_end(ab); 1601 } 1602 1603 int __bpf_prog_charge(struct user_struct *user, u32 pages) 1604 { 1605 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 1606 unsigned long user_bufs; 1607 1608 if (user) { 1609 user_bufs = atomic_long_add_return(pages, &user->locked_vm); 1610 if (user_bufs > memlock_limit) { 1611 atomic_long_sub(pages, &user->locked_vm); 1612 return -EPERM; 1613 } 1614 } 1615 1616 return 0; 1617 } 1618 1619 void __bpf_prog_uncharge(struct user_struct *user, u32 pages) 1620 { 1621 if (user) 1622 atomic_long_sub(pages, &user->locked_vm); 1623 } 1624 1625 static int bpf_prog_charge_memlock(struct bpf_prog *prog) 1626 { 1627 struct user_struct *user = get_current_user(); 1628 int ret; 1629 1630 ret = __bpf_prog_charge(user, prog->pages); 1631 if (ret) { 1632 free_uid(user); 1633 return ret; 1634 } 1635 1636 prog->aux->user = user; 1637 return 0; 1638 } 1639 1640 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) 1641 { 1642 struct user_struct *user = prog->aux->user; 1643 1644 __bpf_prog_uncharge(user, prog->pages); 1645 free_uid(user); 1646 } 1647 1648 static int bpf_prog_alloc_id(struct bpf_prog *prog) 1649 { 1650 int id; 1651 1652 idr_preload(GFP_KERNEL); 1653 spin_lock_bh(&prog_idr_lock); 1654 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 1655 if (id > 0) 1656 prog->aux->id = id; 1657 spin_unlock_bh(&prog_idr_lock); 1658 idr_preload_end(); 1659 1660 /* id is in [1, INT_MAX) */ 1661 if (WARN_ON_ONCE(!id)) 1662 return -ENOSPC; 1663 1664 return id > 0 ? 0 : id; 1665 } 1666 1667 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) 1668 { 1669 /* cBPF to eBPF migrations are currently not in the idr store. 1670 * Offloaded programs are removed from the store when their device 1671 * disappears - even if someone grabs an fd to them they are unusable, 1672 * simply waiting for refcnt to drop to be freed. 1673 */ 1674 if (!prog->aux->id) 1675 return; 1676 1677 if (do_idr_lock) 1678 spin_lock_bh(&prog_idr_lock); 1679 else 1680 __acquire(&prog_idr_lock); 1681 1682 idr_remove(&prog_idr, prog->aux->id); 1683 prog->aux->id = 0; 1684 1685 if (do_idr_lock) 1686 spin_unlock_bh(&prog_idr_lock); 1687 else 1688 __release(&prog_idr_lock); 1689 } 1690 1691 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 1692 { 1693 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 1694 1695 kvfree(aux->func_info); 1696 kfree(aux->func_info_aux); 1697 bpf_prog_uncharge_memlock(aux->prog); 1698 security_bpf_prog_free(aux); 1699 bpf_prog_free(aux->prog); 1700 } 1701 1702 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 1703 { 1704 bpf_prog_kallsyms_del_all(prog); 1705 btf_put(prog->aux->btf); 1706 bpf_prog_free_linfo(prog); 1707 1708 if (deferred) 1709 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 1710 else 1711 __bpf_prog_put_rcu(&prog->aux->rcu); 1712 } 1713 1714 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) 1715 { 1716 if (atomic64_dec_and_test(&prog->aux->refcnt)) { 1717 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 1718 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 1719 /* bpf_prog_free_id() must be called first */ 1720 bpf_prog_free_id(prog, do_idr_lock); 1721 __bpf_prog_put_noref(prog, true); 1722 } 1723 } 1724 1725 void bpf_prog_put(struct bpf_prog *prog) 1726 { 1727 __bpf_prog_put(prog, true); 1728 } 1729 EXPORT_SYMBOL_GPL(bpf_prog_put); 1730 1731 static int bpf_prog_release(struct inode *inode, struct file *filp) 1732 { 1733 struct bpf_prog *prog = filp->private_data; 1734 1735 bpf_prog_put(prog); 1736 return 0; 1737 } 1738 1739 static void bpf_prog_get_stats(const struct bpf_prog *prog, 1740 struct bpf_prog_stats *stats) 1741 { 1742 u64 nsecs = 0, cnt = 0; 1743 int cpu; 1744 1745 for_each_possible_cpu(cpu) { 1746 const struct bpf_prog_stats *st; 1747 unsigned int start; 1748 u64 tnsecs, tcnt; 1749 1750 st = per_cpu_ptr(prog->aux->stats, cpu); 1751 do { 1752 start = u64_stats_fetch_begin_irq(&st->syncp); 1753 tnsecs = st->nsecs; 1754 tcnt = st->cnt; 1755 } while (u64_stats_fetch_retry_irq(&st->syncp, start)); 1756 nsecs += tnsecs; 1757 cnt += tcnt; 1758 } 1759 stats->nsecs = nsecs; 1760 stats->cnt = cnt; 1761 } 1762 1763 #ifdef CONFIG_PROC_FS 1764 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 1765 { 1766 const struct bpf_prog *prog = filp->private_data; 1767 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 1768 struct bpf_prog_stats stats; 1769 1770 bpf_prog_get_stats(prog, &stats); 1771 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 1772 seq_printf(m, 1773 "prog_type:\t%u\n" 1774 "prog_jited:\t%u\n" 1775 "prog_tag:\t%s\n" 1776 "memlock:\t%llu\n" 1777 "prog_id:\t%u\n" 1778 "run_time_ns:\t%llu\n" 1779 "run_cnt:\t%llu\n", 1780 prog->type, 1781 prog->jited, 1782 prog_tag, 1783 prog->pages * 1ULL << PAGE_SHIFT, 1784 prog->aux->id, 1785 stats.nsecs, 1786 stats.cnt); 1787 } 1788 #endif 1789 1790 const struct file_operations bpf_prog_fops = { 1791 #ifdef CONFIG_PROC_FS 1792 .show_fdinfo = bpf_prog_show_fdinfo, 1793 #endif 1794 .release = bpf_prog_release, 1795 .read = bpf_dummy_read, 1796 .write = bpf_dummy_write, 1797 }; 1798 1799 int bpf_prog_new_fd(struct bpf_prog *prog) 1800 { 1801 int ret; 1802 1803 ret = security_bpf_prog(prog); 1804 if (ret < 0) 1805 return ret; 1806 1807 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 1808 O_RDWR | O_CLOEXEC); 1809 } 1810 1811 static struct bpf_prog *____bpf_prog_get(struct fd f) 1812 { 1813 if (!f.file) 1814 return ERR_PTR(-EBADF); 1815 if (f.file->f_op != &bpf_prog_fops) { 1816 fdput(f); 1817 return ERR_PTR(-EINVAL); 1818 } 1819 1820 return f.file->private_data; 1821 } 1822 1823 void bpf_prog_add(struct bpf_prog *prog, int i) 1824 { 1825 atomic64_add(i, &prog->aux->refcnt); 1826 } 1827 EXPORT_SYMBOL_GPL(bpf_prog_add); 1828 1829 void bpf_prog_sub(struct bpf_prog *prog, int i) 1830 { 1831 /* Only to be used for undoing previous bpf_prog_add() in some 1832 * error path. We still know that another entity in our call 1833 * path holds a reference to the program, thus atomic_sub() can 1834 * be safely used in such cases! 1835 */ 1836 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 1837 } 1838 EXPORT_SYMBOL_GPL(bpf_prog_sub); 1839 1840 void bpf_prog_inc(struct bpf_prog *prog) 1841 { 1842 atomic64_inc(&prog->aux->refcnt); 1843 } 1844 EXPORT_SYMBOL_GPL(bpf_prog_inc); 1845 1846 /* prog_idr_lock should have been held */ 1847 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 1848 { 1849 int refold; 1850 1851 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 1852 1853 if (!refold) 1854 return ERR_PTR(-ENOENT); 1855 1856 return prog; 1857 } 1858 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 1859 1860 bool bpf_prog_get_ok(struct bpf_prog *prog, 1861 enum bpf_prog_type *attach_type, bool attach_drv) 1862 { 1863 /* not an attachment, just a refcount inc, always allow */ 1864 if (!attach_type) 1865 return true; 1866 1867 if (prog->type != *attach_type) 1868 return false; 1869 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv) 1870 return false; 1871 1872 return true; 1873 } 1874 1875 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 1876 bool attach_drv) 1877 { 1878 struct fd f = fdget(ufd); 1879 struct bpf_prog *prog; 1880 1881 prog = ____bpf_prog_get(f); 1882 if (IS_ERR(prog)) 1883 return prog; 1884 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 1885 prog = ERR_PTR(-EINVAL); 1886 goto out; 1887 } 1888 1889 bpf_prog_inc(prog); 1890 out: 1891 fdput(f); 1892 return prog; 1893 } 1894 1895 struct bpf_prog *bpf_prog_get(u32 ufd) 1896 { 1897 return __bpf_prog_get(ufd, NULL, false); 1898 } 1899 1900 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 1901 bool attach_drv) 1902 { 1903 return __bpf_prog_get(ufd, &type, attach_drv); 1904 } 1905 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 1906 1907 /* Initially all BPF programs could be loaded w/o specifying 1908 * expected_attach_type. Later for some of them specifying expected_attach_type 1909 * at load time became required so that program could be validated properly. 1910 * Programs of types that are allowed to be loaded both w/ and w/o (for 1911 * backward compatibility) expected_attach_type, should have the default attach 1912 * type assigned to expected_attach_type for the latter case, so that it can be 1913 * validated later at attach time. 1914 * 1915 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 1916 * prog type requires it but has some attach types that have to be backward 1917 * compatible. 1918 */ 1919 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 1920 { 1921 switch (attr->prog_type) { 1922 case BPF_PROG_TYPE_CGROUP_SOCK: 1923 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 1924 * exist so checking for non-zero is the way to go here. 1925 */ 1926 if (!attr->expected_attach_type) 1927 attr->expected_attach_type = 1928 BPF_CGROUP_INET_SOCK_CREATE; 1929 break; 1930 } 1931 } 1932 1933 static int 1934 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 1935 enum bpf_attach_type expected_attach_type, 1936 u32 btf_id, u32 prog_fd) 1937 { 1938 if (btf_id) { 1939 if (btf_id > BTF_MAX_TYPE) 1940 return -EINVAL; 1941 1942 switch (prog_type) { 1943 case BPF_PROG_TYPE_TRACING: 1944 case BPF_PROG_TYPE_LSM: 1945 case BPF_PROG_TYPE_STRUCT_OPS: 1946 case BPF_PROG_TYPE_EXT: 1947 break; 1948 default: 1949 return -EINVAL; 1950 } 1951 } 1952 1953 if (prog_fd && prog_type != BPF_PROG_TYPE_TRACING && 1954 prog_type != BPF_PROG_TYPE_EXT) 1955 return -EINVAL; 1956 1957 switch (prog_type) { 1958 case BPF_PROG_TYPE_CGROUP_SOCK: 1959 switch (expected_attach_type) { 1960 case BPF_CGROUP_INET_SOCK_CREATE: 1961 case BPF_CGROUP_INET4_POST_BIND: 1962 case BPF_CGROUP_INET6_POST_BIND: 1963 return 0; 1964 default: 1965 return -EINVAL; 1966 } 1967 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 1968 switch (expected_attach_type) { 1969 case BPF_CGROUP_INET4_BIND: 1970 case BPF_CGROUP_INET6_BIND: 1971 case BPF_CGROUP_INET4_CONNECT: 1972 case BPF_CGROUP_INET6_CONNECT: 1973 case BPF_CGROUP_UDP4_SENDMSG: 1974 case BPF_CGROUP_UDP6_SENDMSG: 1975 case BPF_CGROUP_UDP4_RECVMSG: 1976 case BPF_CGROUP_UDP6_RECVMSG: 1977 return 0; 1978 default: 1979 return -EINVAL; 1980 } 1981 case BPF_PROG_TYPE_CGROUP_SKB: 1982 switch (expected_attach_type) { 1983 case BPF_CGROUP_INET_INGRESS: 1984 case BPF_CGROUP_INET_EGRESS: 1985 return 0; 1986 default: 1987 return -EINVAL; 1988 } 1989 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 1990 switch (expected_attach_type) { 1991 case BPF_CGROUP_SETSOCKOPT: 1992 case BPF_CGROUP_GETSOCKOPT: 1993 return 0; 1994 default: 1995 return -EINVAL; 1996 } 1997 case BPF_PROG_TYPE_EXT: 1998 if (expected_attach_type) 1999 return -EINVAL; 2000 /* fallthrough */ 2001 default: 2002 return 0; 2003 } 2004 } 2005 2006 /* last field in 'union bpf_attr' used by this command */ 2007 #define BPF_PROG_LOAD_LAST_FIELD attach_prog_fd 2008 2009 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) 2010 { 2011 enum bpf_prog_type type = attr->prog_type; 2012 struct bpf_prog *prog; 2013 int err; 2014 char license[128]; 2015 bool is_gpl; 2016 2017 if (CHECK_ATTR(BPF_PROG_LOAD)) 2018 return -EINVAL; 2019 2020 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2021 BPF_F_ANY_ALIGNMENT | 2022 BPF_F_TEST_STATE_FREQ | 2023 BPF_F_TEST_RND_HI32)) 2024 return -EINVAL; 2025 2026 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2027 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2028 !capable(CAP_SYS_ADMIN)) 2029 return -EPERM; 2030 2031 /* copy eBPF program license from user space */ 2032 if (strncpy_from_user(license, u64_to_user_ptr(attr->license), 2033 sizeof(license) - 1) < 0) 2034 return -EFAULT; 2035 license[sizeof(license) - 1] = 0; 2036 2037 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2038 is_gpl = license_is_gpl_compatible(license); 2039 2040 if (attr->insn_cnt == 0 || 2041 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) 2042 return -E2BIG; 2043 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2044 type != BPF_PROG_TYPE_CGROUP_SKB && 2045 !capable(CAP_SYS_ADMIN)) 2046 return -EPERM; 2047 2048 bpf_prog_load_fixup_attach_type(attr); 2049 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2050 attr->attach_btf_id, 2051 attr->attach_prog_fd)) 2052 return -EINVAL; 2053 2054 /* plain bpf_prog allocation */ 2055 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2056 if (!prog) 2057 return -ENOMEM; 2058 2059 prog->expected_attach_type = attr->expected_attach_type; 2060 prog->aux->attach_btf_id = attr->attach_btf_id; 2061 if (attr->attach_prog_fd) { 2062 struct bpf_prog *tgt_prog; 2063 2064 tgt_prog = bpf_prog_get(attr->attach_prog_fd); 2065 if (IS_ERR(tgt_prog)) { 2066 err = PTR_ERR(tgt_prog); 2067 goto free_prog_nouncharge; 2068 } 2069 prog->aux->linked_prog = tgt_prog; 2070 } 2071 2072 prog->aux->offload_requested = !!attr->prog_ifindex; 2073 2074 err = security_bpf_prog_alloc(prog->aux); 2075 if (err) 2076 goto free_prog_nouncharge; 2077 2078 err = bpf_prog_charge_memlock(prog); 2079 if (err) 2080 goto free_prog_sec; 2081 2082 prog->len = attr->insn_cnt; 2083 2084 err = -EFAULT; 2085 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), 2086 bpf_prog_insn_size(prog)) != 0) 2087 goto free_prog; 2088 2089 prog->orig_prog = NULL; 2090 prog->jited = 0; 2091 2092 atomic64_set(&prog->aux->refcnt, 1); 2093 prog->gpl_compatible = is_gpl ? 1 : 0; 2094 2095 if (bpf_prog_is_dev_bound(prog->aux)) { 2096 err = bpf_prog_offload_init(prog, attr); 2097 if (err) 2098 goto free_prog; 2099 } 2100 2101 /* find program type: socket_filter vs tracing_filter */ 2102 err = find_prog_type(type, prog); 2103 if (err < 0) 2104 goto free_prog; 2105 2106 prog->aux->load_time = ktime_get_boottime_ns(); 2107 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2108 sizeof(attr->prog_name)); 2109 if (err < 0) 2110 goto free_prog; 2111 2112 /* run eBPF verifier */ 2113 err = bpf_check(&prog, attr, uattr); 2114 if (err < 0) 2115 goto free_used_maps; 2116 2117 prog = bpf_prog_select_runtime(prog, &err); 2118 if (err < 0) 2119 goto free_used_maps; 2120 2121 err = bpf_prog_alloc_id(prog); 2122 if (err) 2123 goto free_used_maps; 2124 2125 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2126 * effectively publicly exposed. However, retrieving via 2127 * bpf_prog_get_fd_by_id() will take another reference, 2128 * therefore it cannot be gone underneath us. 2129 * 2130 * Only for the time /after/ successful bpf_prog_new_fd() 2131 * and before returning to userspace, we might just hold 2132 * one reference and any parallel close on that fd could 2133 * rip everything out. Hence, below notifications must 2134 * happen before bpf_prog_new_fd(). 2135 * 2136 * Also, any failure handling from this point onwards must 2137 * be using bpf_prog_put() given the program is exposed. 2138 */ 2139 bpf_prog_kallsyms_add(prog); 2140 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2141 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2142 2143 err = bpf_prog_new_fd(prog); 2144 if (err < 0) 2145 bpf_prog_put(prog); 2146 return err; 2147 2148 free_used_maps: 2149 /* In case we have subprogs, we need to wait for a grace 2150 * period before we can tear down JIT memory since symbols 2151 * are already exposed under kallsyms. 2152 */ 2153 __bpf_prog_put_noref(prog, prog->aux->func_cnt); 2154 return err; 2155 free_prog: 2156 bpf_prog_uncharge_memlock(prog); 2157 free_prog_sec: 2158 security_bpf_prog_free(prog->aux); 2159 free_prog_nouncharge: 2160 bpf_prog_free(prog); 2161 return err; 2162 } 2163 2164 #define BPF_OBJ_LAST_FIELD file_flags 2165 2166 static int bpf_obj_pin(const union bpf_attr *attr) 2167 { 2168 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0) 2169 return -EINVAL; 2170 2171 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); 2172 } 2173 2174 static int bpf_obj_get(const union bpf_attr *attr) 2175 { 2176 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2177 attr->file_flags & ~BPF_OBJ_FLAG_MASK) 2178 return -EINVAL; 2179 2180 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname), 2181 attr->file_flags); 2182 } 2183 2184 void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops, 2185 struct bpf_prog *prog) 2186 { 2187 atomic64_set(&link->refcnt, 1); 2188 link->ops = ops; 2189 link->prog = prog; 2190 } 2191 2192 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2193 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2194 * anon_inode's release() call. This helper manages marking bpf_link as 2195 * defunct, releases anon_inode file and puts reserved FD. 2196 */ 2197 void bpf_link_cleanup(struct bpf_link *link, struct file *link_file, 2198 int link_fd) 2199 { 2200 link->prog = NULL; 2201 fput(link_file); 2202 put_unused_fd(link_fd); 2203 } 2204 2205 void bpf_link_inc(struct bpf_link *link) 2206 { 2207 atomic64_inc(&link->refcnt); 2208 } 2209 2210 /* bpf_link_free is guaranteed to be called from process context */ 2211 static void bpf_link_free(struct bpf_link *link) 2212 { 2213 if (link->prog) { 2214 /* detach BPF program, clean up used resources */ 2215 link->ops->release(link); 2216 bpf_prog_put(link->prog); 2217 } 2218 /* free bpf_link and its containing memory */ 2219 link->ops->dealloc(link); 2220 } 2221 2222 static void bpf_link_put_deferred(struct work_struct *work) 2223 { 2224 struct bpf_link *link = container_of(work, struct bpf_link, work); 2225 2226 bpf_link_free(link); 2227 } 2228 2229 /* bpf_link_put can be called from atomic context, but ensures that resources 2230 * are freed from process context 2231 */ 2232 void bpf_link_put(struct bpf_link *link) 2233 { 2234 if (!atomic64_dec_and_test(&link->refcnt)) 2235 return; 2236 2237 if (in_atomic()) { 2238 INIT_WORK(&link->work, bpf_link_put_deferred); 2239 schedule_work(&link->work); 2240 } else { 2241 bpf_link_free(link); 2242 } 2243 } 2244 2245 static int bpf_link_release(struct inode *inode, struct file *filp) 2246 { 2247 struct bpf_link *link = filp->private_data; 2248 2249 bpf_link_put(link); 2250 return 0; 2251 } 2252 2253 #ifdef CONFIG_PROC_FS 2254 static const struct bpf_link_ops bpf_raw_tp_lops; 2255 static const struct bpf_link_ops bpf_tracing_link_lops; 2256 2257 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 2258 { 2259 const struct bpf_link *link = filp->private_data; 2260 const struct bpf_prog *prog = link->prog; 2261 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2262 const char *link_type; 2263 2264 if (link->ops == &bpf_raw_tp_lops) 2265 link_type = "raw_tracepoint"; 2266 else if (link->ops == &bpf_tracing_link_lops) 2267 link_type = "tracing"; 2268 #ifdef CONFIG_CGROUP_BPF 2269 else if (link->ops == &bpf_cgroup_link_lops) 2270 link_type = "cgroup"; 2271 #endif 2272 else 2273 link_type = "unknown"; 2274 2275 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2276 seq_printf(m, 2277 "link_type:\t%s\n" 2278 "prog_tag:\t%s\n" 2279 "prog_id:\t%u\n", 2280 link_type, 2281 prog_tag, 2282 prog->aux->id); 2283 } 2284 #endif 2285 2286 static const struct file_operations bpf_link_fops = { 2287 #ifdef CONFIG_PROC_FS 2288 .show_fdinfo = bpf_link_show_fdinfo, 2289 #endif 2290 .release = bpf_link_release, 2291 .read = bpf_dummy_read, 2292 .write = bpf_dummy_write, 2293 }; 2294 2295 int bpf_link_new_fd(struct bpf_link *link) 2296 { 2297 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 2298 } 2299 2300 /* Similar to bpf_link_new_fd, create anon_inode for given bpf_link, but 2301 * instead of immediately installing fd in fdtable, just reserve it and 2302 * return. Caller then need to either install it with fd_install(fd, file) or 2303 * release with put_unused_fd(fd). 2304 * This is useful for cases when bpf_link attachment/detachment are 2305 * complicated and expensive operations and should be delayed until all the fd 2306 * reservation and anon_inode creation succeeds. 2307 */ 2308 struct file *bpf_link_new_file(struct bpf_link *link, int *reserved_fd) 2309 { 2310 struct file *file; 2311 int fd; 2312 2313 fd = get_unused_fd_flags(O_CLOEXEC); 2314 if (fd < 0) 2315 return ERR_PTR(fd); 2316 2317 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 2318 if (IS_ERR(file)) { 2319 put_unused_fd(fd); 2320 return file; 2321 } 2322 2323 *reserved_fd = fd; 2324 return file; 2325 } 2326 2327 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 2328 { 2329 struct fd f = fdget(ufd); 2330 struct bpf_link *link; 2331 2332 if (!f.file) 2333 return ERR_PTR(-EBADF); 2334 if (f.file->f_op != &bpf_link_fops) { 2335 fdput(f); 2336 return ERR_PTR(-EINVAL); 2337 } 2338 2339 link = f.file->private_data; 2340 bpf_link_inc(link); 2341 fdput(f); 2342 2343 return link; 2344 } 2345 2346 struct bpf_tracing_link { 2347 struct bpf_link link; 2348 }; 2349 2350 static void bpf_tracing_link_release(struct bpf_link *link) 2351 { 2352 WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog)); 2353 } 2354 2355 static void bpf_tracing_link_dealloc(struct bpf_link *link) 2356 { 2357 struct bpf_tracing_link *tr_link = 2358 container_of(link, struct bpf_tracing_link, link); 2359 2360 kfree(tr_link); 2361 } 2362 2363 static const struct bpf_link_ops bpf_tracing_link_lops = { 2364 .release = bpf_tracing_link_release, 2365 .dealloc = bpf_tracing_link_dealloc, 2366 }; 2367 2368 static int bpf_tracing_prog_attach(struct bpf_prog *prog) 2369 { 2370 struct bpf_tracing_link *link; 2371 struct file *link_file; 2372 int link_fd, err; 2373 2374 switch (prog->type) { 2375 case BPF_PROG_TYPE_TRACING: 2376 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 2377 prog->expected_attach_type != BPF_TRACE_FEXIT && 2378 prog->expected_attach_type != BPF_MODIFY_RETURN) { 2379 err = -EINVAL; 2380 goto out_put_prog; 2381 } 2382 break; 2383 case BPF_PROG_TYPE_EXT: 2384 if (prog->expected_attach_type != 0) { 2385 err = -EINVAL; 2386 goto out_put_prog; 2387 } 2388 break; 2389 case BPF_PROG_TYPE_LSM: 2390 if (prog->expected_attach_type != BPF_LSM_MAC) { 2391 err = -EINVAL; 2392 goto out_put_prog; 2393 } 2394 break; 2395 default: 2396 err = -EINVAL; 2397 goto out_put_prog; 2398 } 2399 2400 link = kzalloc(sizeof(*link), GFP_USER); 2401 if (!link) { 2402 err = -ENOMEM; 2403 goto out_put_prog; 2404 } 2405 bpf_link_init(&link->link, &bpf_tracing_link_lops, prog); 2406 2407 link_file = bpf_link_new_file(&link->link, &link_fd); 2408 if (IS_ERR(link_file)) { 2409 kfree(link); 2410 err = PTR_ERR(link_file); 2411 goto out_put_prog; 2412 } 2413 2414 err = bpf_trampoline_link_prog(prog); 2415 if (err) { 2416 bpf_link_cleanup(&link->link, link_file, link_fd); 2417 goto out_put_prog; 2418 } 2419 2420 fd_install(link_fd, link_file); 2421 return link_fd; 2422 2423 out_put_prog: 2424 bpf_prog_put(prog); 2425 return err; 2426 } 2427 2428 struct bpf_raw_tp_link { 2429 struct bpf_link link; 2430 struct bpf_raw_event_map *btp; 2431 }; 2432 2433 static void bpf_raw_tp_link_release(struct bpf_link *link) 2434 { 2435 struct bpf_raw_tp_link *raw_tp = 2436 container_of(link, struct bpf_raw_tp_link, link); 2437 2438 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 2439 bpf_put_raw_tracepoint(raw_tp->btp); 2440 } 2441 2442 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 2443 { 2444 struct bpf_raw_tp_link *raw_tp = 2445 container_of(link, struct bpf_raw_tp_link, link); 2446 2447 kfree(raw_tp); 2448 } 2449 2450 static const struct bpf_link_ops bpf_raw_tp_lops = { 2451 .release = bpf_raw_tp_link_release, 2452 .dealloc = bpf_raw_tp_link_dealloc, 2453 }; 2454 2455 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 2456 2457 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 2458 { 2459 struct bpf_raw_tp_link *link; 2460 struct bpf_raw_event_map *btp; 2461 struct file *link_file; 2462 struct bpf_prog *prog; 2463 const char *tp_name; 2464 char buf[128]; 2465 int link_fd, err; 2466 2467 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 2468 return -EINVAL; 2469 2470 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 2471 if (IS_ERR(prog)) 2472 return PTR_ERR(prog); 2473 2474 switch (prog->type) { 2475 case BPF_PROG_TYPE_TRACING: 2476 case BPF_PROG_TYPE_EXT: 2477 case BPF_PROG_TYPE_LSM: 2478 if (attr->raw_tracepoint.name) { 2479 /* The attach point for this category of programs 2480 * should be specified via btf_id during program load. 2481 */ 2482 err = -EINVAL; 2483 goto out_put_prog; 2484 } 2485 if (prog->type == BPF_PROG_TYPE_TRACING && 2486 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 2487 tp_name = prog->aux->attach_func_name; 2488 break; 2489 } 2490 return bpf_tracing_prog_attach(prog); 2491 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2492 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2493 if (strncpy_from_user(buf, 2494 u64_to_user_ptr(attr->raw_tracepoint.name), 2495 sizeof(buf) - 1) < 0) { 2496 err = -EFAULT; 2497 goto out_put_prog; 2498 } 2499 buf[sizeof(buf) - 1] = 0; 2500 tp_name = buf; 2501 break; 2502 default: 2503 err = -EINVAL; 2504 goto out_put_prog; 2505 } 2506 2507 btp = bpf_get_raw_tracepoint(tp_name); 2508 if (!btp) { 2509 err = -ENOENT; 2510 goto out_put_prog; 2511 } 2512 2513 link = kzalloc(sizeof(*link), GFP_USER); 2514 if (!link) { 2515 err = -ENOMEM; 2516 goto out_put_btp; 2517 } 2518 bpf_link_init(&link->link, &bpf_raw_tp_lops, prog); 2519 link->btp = btp; 2520 2521 link_file = bpf_link_new_file(&link->link, &link_fd); 2522 if (IS_ERR(link_file)) { 2523 kfree(link); 2524 err = PTR_ERR(link_file); 2525 goto out_put_btp; 2526 } 2527 2528 err = bpf_probe_register(link->btp, prog); 2529 if (err) { 2530 bpf_link_cleanup(&link->link, link_file, link_fd); 2531 goto out_put_btp; 2532 } 2533 2534 fd_install(link_fd, link_file); 2535 return link_fd; 2536 2537 out_put_btp: 2538 bpf_put_raw_tracepoint(btp); 2539 out_put_prog: 2540 bpf_prog_put(prog); 2541 return err; 2542 } 2543 2544 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 2545 enum bpf_attach_type attach_type) 2546 { 2547 switch (prog->type) { 2548 case BPF_PROG_TYPE_CGROUP_SOCK: 2549 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2550 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2551 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 2552 case BPF_PROG_TYPE_CGROUP_SKB: 2553 return prog->enforce_expected_attach_type && 2554 prog->expected_attach_type != attach_type ? 2555 -EINVAL : 0; 2556 default: 2557 return 0; 2558 } 2559 } 2560 2561 static enum bpf_prog_type 2562 attach_type_to_prog_type(enum bpf_attach_type attach_type) 2563 { 2564 switch (attach_type) { 2565 case BPF_CGROUP_INET_INGRESS: 2566 case BPF_CGROUP_INET_EGRESS: 2567 return BPF_PROG_TYPE_CGROUP_SKB; 2568 break; 2569 case BPF_CGROUP_INET_SOCK_CREATE: 2570 case BPF_CGROUP_INET4_POST_BIND: 2571 case BPF_CGROUP_INET6_POST_BIND: 2572 return BPF_PROG_TYPE_CGROUP_SOCK; 2573 case BPF_CGROUP_INET4_BIND: 2574 case BPF_CGROUP_INET6_BIND: 2575 case BPF_CGROUP_INET4_CONNECT: 2576 case BPF_CGROUP_INET6_CONNECT: 2577 case BPF_CGROUP_UDP4_SENDMSG: 2578 case BPF_CGROUP_UDP6_SENDMSG: 2579 case BPF_CGROUP_UDP4_RECVMSG: 2580 case BPF_CGROUP_UDP6_RECVMSG: 2581 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 2582 case BPF_CGROUP_SOCK_OPS: 2583 return BPF_PROG_TYPE_SOCK_OPS; 2584 case BPF_CGROUP_DEVICE: 2585 return BPF_PROG_TYPE_CGROUP_DEVICE; 2586 case BPF_SK_MSG_VERDICT: 2587 return BPF_PROG_TYPE_SK_MSG; 2588 case BPF_SK_SKB_STREAM_PARSER: 2589 case BPF_SK_SKB_STREAM_VERDICT: 2590 return BPF_PROG_TYPE_SK_SKB; 2591 case BPF_LIRC_MODE2: 2592 return BPF_PROG_TYPE_LIRC_MODE2; 2593 case BPF_FLOW_DISSECTOR: 2594 return BPF_PROG_TYPE_FLOW_DISSECTOR; 2595 case BPF_CGROUP_SYSCTL: 2596 return BPF_PROG_TYPE_CGROUP_SYSCTL; 2597 case BPF_CGROUP_GETSOCKOPT: 2598 case BPF_CGROUP_SETSOCKOPT: 2599 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 2600 default: 2601 return BPF_PROG_TYPE_UNSPEC; 2602 } 2603 } 2604 2605 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd 2606 2607 #define BPF_F_ATTACH_MASK \ 2608 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) 2609 2610 static int bpf_prog_attach(const union bpf_attr *attr) 2611 { 2612 enum bpf_prog_type ptype; 2613 struct bpf_prog *prog; 2614 int ret; 2615 2616 if (!capable(CAP_NET_ADMIN)) 2617 return -EPERM; 2618 2619 if (CHECK_ATTR(BPF_PROG_ATTACH)) 2620 return -EINVAL; 2621 2622 if (attr->attach_flags & ~BPF_F_ATTACH_MASK) 2623 return -EINVAL; 2624 2625 ptype = attach_type_to_prog_type(attr->attach_type); 2626 if (ptype == BPF_PROG_TYPE_UNSPEC) 2627 return -EINVAL; 2628 2629 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 2630 if (IS_ERR(prog)) 2631 return PTR_ERR(prog); 2632 2633 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 2634 bpf_prog_put(prog); 2635 return -EINVAL; 2636 } 2637 2638 switch (ptype) { 2639 case BPF_PROG_TYPE_SK_SKB: 2640 case BPF_PROG_TYPE_SK_MSG: 2641 ret = sock_map_get_from_fd(attr, prog); 2642 break; 2643 case BPF_PROG_TYPE_LIRC_MODE2: 2644 ret = lirc_prog_attach(attr, prog); 2645 break; 2646 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2647 ret = skb_flow_dissector_bpf_prog_attach(attr, prog); 2648 break; 2649 case BPF_PROG_TYPE_CGROUP_DEVICE: 2650 case BPF_PROG_TYPE_CGROUP_SKB: 2651 case BPF_PROG_TYPE_CGROUP_SOCK: 2652 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2653 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2654 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2655 case BPF_PROG_TYPE_SOCK_OPS: 2656 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 2657 break; 2658 default: 2659 ret = -EINVAL; 2660 } 2661 2662 if (ret) 2663 bpf_prog_put(prog); 2664 return ret; 2665 } 2666 2667 #define BPF_PROG_DETACH_LAST_FIELD attach_type 2668 2669 static int bpf_prog_detach(const union bpf_attr *attr) 2670 { 2671 enum bpf_prog_type ptype; 2672 2673 if (!capable(CAP_NET_ADMIN)) 2674 return -EPERM; 2675 2676 if (CHECK_ATTR(BPF_PROG_DETACH)) 2677 return -EINVAL; 2678 2679 ptype = attach_type_to_prog_type(attr->attach_type); 2680 2681 switch (ptype) { 2682 case BPF_PROG_TYPE_SK_MSG: 2683 case BPF_PROG_TYPE_SK_SKB: 2684 return sock_map_get_from_fd(attr, NULL); 2685 case BPF_PROG_TYPE_LIRC_MODE2: 2686 return lirc_prog_detach(attr); 2687 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2688 return skb_flow_dissector_bpf_prog_detach(attr); 2689 case BPF_PROG_TYPE_CGROUP_DEVICE: 2690 case BPF_PROG_TYPE_CGROUP_SKB: 2691 case BPF_PROG_TYPE_CGROUP_SOCK: 2692 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2693 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2694 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2695 case BPF_PROG_TYPE_SOCK_OPS: 2696 return cgroup_bpf_prog_detach(attr, ptype); 2697 default: 2698 return -EINVAL; 2699 } 2700 } 2701 2702 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt 2703 2704 static int bpf_prog_query(const union bpf_attr *attr, 2705 union bpf_attr __user *uattr) 2706 { 2707 if (!capable(CAP_NET_ADMIN)) 2708 return -EPERM; 2709 if (CHECK_ATTR(BPF_PROG_QUERY)) 2710 return -EINVAL; 2711 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 2712 return -EINVAL; 2713 2714 switch (attr->query.attach_type) { 2715 case BPF_CGROUP_INET_INGRESS: 2716 case BPF_CGROUP_INET_EGRESS: 2717 case BPF_CGROUP_INET_SOCK_CREATE: 2718 case BPF_CGROUP_INET4_BIND: 2719 case BPF_CGROUP_INET6_BIND: 2720 case BPF_CGROUP_INET4_POST_BIND: 2721 case BPF_CGROUP_INET6_POST_BIND: 2722 case BPF_CGROUP_INET4_CONNECT: 2723 case BPF_CGROUP_INET6_CONNECT: 2724 case BPF_CGROUP_UDP4_SENDMSG: 2725 case BPF_CGROUP_UDP6_SENDMSG: 2726 case BPF_CGROUP_UDP4_RECVMSG: 2727 case BPF_CGROUP_UDP6_RECVMSG: 2728 case BPF_CGROUP_SOCK_OPS: 2729 case BPF_CGROUP_DEVICE: 2730 case BPF_CGROUP_SYSCTL: 2731 case BPF_CGROUP_GETSOCKOPT: 2732 case BPF_CGROUP_SETSOCKOPT: 2733 return cgroup_bpf_prog_query(attr, uattr); 2734 case BPF_LIRC_MODE2: 2735 return lirc_prog_query(attr, uattr); 2736 case BPF_FLOW_DISSECTOR: 2737 return skb_flow_dissector_prog_query(attr, uattr); 2738 default: 2739 return -EINVAL; 2740 } 2741 } 2742 2743 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out 2744 2745 static int bpf_prog_test_run(const union bpf_attr *attr, 2746 union bpf_attr __user *uattr) 2747 { 2748 struct bpf_prog *prog; 2749 int ret = -ENOTSUPP; 2750 2751 if (!capable(CAP_SYS_ADMIN)) 2752 return -EPERM; 2753 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 2754 return -EINVAL; 2755 2756 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 2757 (!attr->test.ctx_size_in && attr->test.ctx_in)) 2758 return -EINVAL; 2759 2760 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 2761 (!attr->test.ctx_size_out && attr->test.ctx_out)) 2762 return -EINVAL; 2763 2764 prog = bpf_prog_get(attr->test.prog_fd); 2765 if (IS_ERR(prog)) 2766 return PTR_ERR(prog); 2767 2768 if (prog->aux->ops->test_run) 2769 ret = prog->aux->ops->test_run(prog, attr, uattr); 2770 2771 bpf_prog_put(prog); 2772 return ret; 2773 } 2774 2775 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 2776 2777 static int bpf_obj_get_next_id(const union bpf_attr *attr, 2778 union bpf_attr __user *uattr, 2779 struct idr *idr, 2780 spinlock_t *lock) 2781 { 2782 u32 next_id = attr->start_id; 2783 int err = 0; 2784 2785 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 2786 return -EINVAL; 2787 2788 if (!capable(CAP_SYS_ADMIN)) 2789 return -EPERM; 2790 2791 next_id++; 2792 spin_lock_bh(lock); 2793 if (!idr_get_next(idr, &next_id)) 2794 err = -ENOENT; 2795 spin_unlock_bh(lock); 2796 2797 if (!err) 2798 err = put_user(next_id, &uattr->next_id); 2799 2800 return err; 2801 } 2802 2803 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 2804 2805 struct bpf_prog *bpf_prog_by_id(u32 id) 2806 { 2807 struct bpf_prog *prog; 2808 2809 if (!id) 2810 return ERR_PTR(-ENOENT); 2811 2812 spin_lock_bh(&prog_idr_lock); 2813 prog = idr_find(&prog_idr, id); 2814 if (prog) 2815 prog = bpf_prog_inc_not_zero(prog); 2816 else 2817 prog = ERR_PTR(-ENOENT); 2818 spin_unlock_bh(&prog_idr_lock); 2819 return prog; 2820 } 2821 2822 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 2823 { 2824 struct bpf_prog *prog; 2825 u32 id = attr->prog_id; 2826 int fd; 2827 2828 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 2829 return -EINVAL; 2830 2831 if (!capable(CAP_SYS_ADMIN)) 2832 return -EPERM; 2833 2834 prog = bpf_prog_by_id(id); 2835 if (IS_ERR(prog)) 2836 return PTR_ERR(prog); 2837 2838 fd = bpf_prog_new_fd(prog); 2839 if (fd < 0) 2840 bpf_prog_put(prog); 2841 2842 return fd; 2843 } 2844 2845 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 2846 2847 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 2848 { 2849 struct bpf_map *map; 2850 u32 id = attr->map_id; 2851 int f_flags; 2852 int fd; 2853 2854 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 2855 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 2856 return -EINVAL; 2857 2858 if (!capable(CAP_SYS_ADMIN)) 2859 return -EPERM; 2860 2861 f_flags = bpf_get_file_flag(attr->open_flags); 2862 if (f_flags < 0) 2863 return f_flags; 2864 2865 spin_lock_bh(&map_idr_lock); 2866 map = idr_find(&map_idr, id); 2867 if (map) 2868 map = __bpf_map_inc_not_zero(map, true); 2869 else 2870 map = ERR_PTR(-ENOENT); 2871 spin_unlock_bh(&map_idr_lock); 2872 2873 if (IS_ERR(map)) 2874 return PTR_ERR(map); 2875 2876 fd = bpf_map_new_fd(map, f_flags); 2877 if (fd < 0) 2878 bpf_map_put_with_uref(map); 2879 2880 return fd; 2881 } 2882 2883 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 2884 unsigned long addr, u32 *off, 2885 u32 *type) 2886 { 2887 const struct bpf_map *map; 2888 int i; 2889 2890 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 2891 map = prog->aux->used_maps[i]; 2892 if (map == (void *)addr) { 2893 *type = BPF_PSEUDO_MAP_FD; 2894 return map; 2895 } 2896 if (!map->ops->map_direct_value_meta) 2897 continue; 2898 if (!map->ops->map_direct_value_meta(map, addr, off)) { 2899 *type = BPF_PSEUDO_MAP_VALUE; 2900 return map; 2901 } 2902 } 2903 2904 return NULL; 2905 } 2906 2907 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) 2908 { 2909 const struct bpf_map *map; 2910 struct bpf_insn *insns; 2911 u32 off, type; 2912 u64 imm; 2913 int i; 2914 2915 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 2916 GFP_USER); 2917 if (!insns) 2918 return insns; 2919 2920 for (i = 0; i < prog->len; i++) { 2921 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { 2922 insns[i].code = BPF_JMP | BPF_CALL; 2923 insns[i].imm = BPF_FUNC_tail_call; 2924 /* fall-through */ 2925 } 2926 if (insns[i].code == (BPF_JMP | BPF_CALL) || 2927 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { 2928 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) 2929 insns[i].code = BPF_JMP | BPF_CALL; 2930 if (!bpf_dump_raw_ok()) 2931 insns[i].imm = 0; 2932 continue; 2933 } 2934 2935 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) 2936 continue; 2937 2938 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 2939 map = bpf_map_from_imm(prog, imm, &off, &type); 2940 if (map) { 2941 insns[i].src_reg = type; 2942 insns[i].imm = map->id; 2943 insns[i + 1].imm = off; 2944 continue; 2945 } 2946 } 2947 2948 return insns; 2949 } 2950 2951 static int set_info_rec_size(struct bpf_prog_info *info) 2952 { 2953 /* 2954 * Ensure info.*_rec_size is the same as kernel expected size 2955 * 2956 * or 2957 * 2958 * Only allow zero *_rec_size if both _rec_size and _cnt are 2959 * zero. In this case, the kernel will set the expected 2960 * _rec_size back to the info. 2961 */ 2962 2963 if ((info->nr_func_info || info->func_info_rec_size) && 2964 info->func_info_rec_size != sizeof(struct bpf_func_info)) 2965 return -EINVAL; 2966 2967 if ((info->nr_line_info || info->line_info_rec_size) && 2968 info->line_info_rec_size != sizeof(struct bpf_line_info)) 2969 return -EINVAL; 2970 2971 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 2972 info->jited_line_info_rec_size != sizeof(__u64)) 2973 return -EINVAL; 2974 2975 info->func_info_rec_size = sizeof(struct bpf_func_info); 2976 info->line_info_rec_size = sizeof(struct bpf_line_info); 2977 info->jited_line_info_rec_size = sizeof(__u64); 2978 2979 return 0; 2980 } 2981 2982 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, 2983 const union bpf_attr *attr, 2984 union bpf_attr __user *uattr) 2985 { 2986 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 2987 struct bpf_prog_info info; 2988 u32 info_len = attr->info.info_len; 2989 struct bpf_prog_stats stats; 2990 char __user *uinsns; 2991 u32 ulen; 2992 int err; 2993 2994 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 2995 if (err) 2996 return err; 2997 info_len = min_t(u32, sizeof(info), info_len); 2998 2999 memset(&info, 0, sizeof(info)); 3000 if (copy_from_user(&info, uinfo, info_len)) 3001 return -EFAULT; 3002 3003 info.type = prog->type; 3004 info.id = prog->aux->id; 3005 info.load_time = prog->aux->load_time; 3006 info.created_by_uid = from_kuid_munged(current_user_ns(), 3007 prog->aux->user->uid); 3008 info.gpl_compatible = prog->gpl_compatible; 3009 3010 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 3011 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 3012 3013 ulen = info.nr_map_ids; 3014 info.nr_map_ids = prog->aux->used_map_cnt; 3015 ulen = min_t(u32, info.nr_map_ids, ulen); 3016 if (ulen) { 3017 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 3018 u32 i; 3019 3020 for (i = 0; i < ulen; i++) 3021 if (put_user(prog->aux->used_maps[i]->id, 3022 &user_map_ids[i])) 3023 return -EFAULT; 3024 } 3025 3026 err = set_info_rec_size(&info); 3027 if (err) 3028 return err; 3029 3030 bpf_prog_get_stats(prog, &stats); 3031 info.run_time_ns = stats.nsecs; 3032 info.run_cnt = stats.cnt; 3033 3034 if (!capable(CAP_SYS_ADMIN)) { 3035 info.jited_prog_len = 0; 3036 info.xlated_prog_len = 0; 3037 info.nr_jited_ksyms = 0; 3038 info.nr_jited_func_lens = 0; 3039 info.nr_func_info = 0; 3040 info.nr_line_info = 0; 3041 info.nr_jited_line_info = 0; 3042 goto done; 3043 } 3044 3045 ulen = info.xlated_prog_len; 3046 info.xlated_prog_len = bpf_prog_insn_size(prog); 3047 if (info.xlated_prog_len && ulen) { 3048 struct bpf_insn *insns_sanitized; 3049 bool fault; 3050 3051 if (prog->blinded && !bpf_dump_raw_ok()) { 3052 info.xlated_prog_insns = 0; 3053 goto done; 3054 } 3055 insns_sanitized = bpf_insn_prepare_dump(prog); 3056 if (!insns_sanitized) 3057 return -ENOMEM; 3058 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 3059 ulen = min_t(u32, info.xlated_prog_len, ulen); 3060 fault = copy_to_user(uinsns, insns_sanitized, ulen); 3061 kfree(insns_sanitized); 3062 if (fault) 3063 return -EFAULT; 3064 } 3065 3066 if (bpf_prog_is_dev_bound(prog->aux)) { 3067 err = bpf_prog_offload_info_fill(&info, prog); 3068 if (err) 3069 return err; 3070 goto done; 3071 } 3072 3073 /* NOTE: the following code is supposed to be skipped for offload. 3074 * bpf_prog_offload_info_fill() is the place to fill similar fields 3075 * for offload. 3076 */ 3077 ulen = info.jited_prog_len; 3078 if (prog->aux->func_cnt) { 3079 u32 i; 3080 3081 info.jited_prog_len = 0; 3082 for (i = 0; i < prog->aux->func_cnt; i++) 3083 info.jited_prog_len += prog->aux->func[i]->jited_len; 3084 } else { 3085 info.jited_prog_len = prog->jited_len; 3086 } 3087 3088 if (info.jited_prog_len && ulen) { 3089 if (bpf_dump_raw_ok()) { 3090 uinsns = u64_to_user_ptr(info.jited_prog_insns); 3091 ulen = min_t(u32, info.jited_prog_len, ulen); 3092 3093 /* for multi-function programs, copy the JITed 3094 * instructions for all the functions 3095 */ 3096 if (prog->aux->func_cnt) { 3097 u32 len, free, i; 3098 u8 *img; 3099 3100 free = ulen; 3101 for (i = 0; i < prog->aux->func_cnt; i++) { 3102 len = prog->aux->func[i]->jited_len; 3103 len = min_t(u32, len, free); 3104 img = (u8 *) prog->aux->func[i]->bpf_func; 3105 if (copy_to_user(uinsns, img, len)) 3106 return -EFAULT; 3107 uinsns += len; 3108 free -= len; 3109 if (!free) 3110 break; 3111 } 3112 } else { 3113 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 3114 return -EFAULT; 3115 } 3116 } else { 3117 info.jited_prog_insns = 0; 3118 } 3119 } 3120 3121 ulen = info.nr_jited_ksyms; 3122 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 3123 if (ulen) { 3124 if (bpf_dump_raw_ok()) { 3125 unsigned long ksym_addr; 3126 u64 __user *user_ksyms; 3127 u32 i; 3128 3129 /* copy the address of the kernel symbol 3130 * corresponding to each function 3131 */ 3132 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 3133 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 3134 if (prog->aux->func_cnt) { 3135 for (i = 0; i < ulen; i++) { 3136 ksym_addr = (unsigned long) 3137 prog->aux->func[i]->bpf_func; 3138 if (put_user((u64) ksym_addr, 3139 &user_ksyms[i])) 3140 return -EFAULT; 3141 } 3142 } else { 3143 ksym_addr = (unsigned long) prog->bpf_func; 3144 if (put_user((u64) ksym_addr, &user_ksyms[0])) 3145 return -EFAULT; 3146 } 3147 } else { 3148 info.jited_ksyms = 0; 3149 } 3150 } 3151 3152 ulen = info.nr_jited_func_lens; 3153 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 3154 if (ulen) { 3155 if (bpf_dump_raw_ok()) { 3156 u32 __user *user_lens; 3157 u32 func_len, i; 3158 3159 /* copy the JITed image lengths for each function */ 3160 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 3161 user_lens = u64_to_user_ptr(info.jited_func_lens); 3162 if (prog->aux->func_cnt) { 3163 for (i = 0; i < ulen; i++) { 3164 func_len = 3165 prog->aux->func[i]->jited_len; 3166 if (put_user(func_len, &user_lens[i])) 3167 return -EFAULT; 3168 } 3169 } else { 3170 func_len = prog->jited_len; 3171 if (put_user(func_len, &user_lens[0])) 3172 return -EFAULT; 3173 } 3174 } else { 3175 info.jited_func_lens = 0; 3176 } 3177 } 3178 3179 if (prog->aux->btf) 3180 info.btf_id = btf_id(prog->aux->btf); 3181 3182 ulen = info.nr_func_info; 3183 info.nr_func_info = prog->aux->func_info_cnt; 3184 if (info.nr_func_info && ulen) { 3185 char __user *user_finfo; 3186 3187 user_finfo = u64_to_user_ptr(info.func_info); 3188 ulen = min_t(u32, info.nr_func_info, ulen); 3189 if (copy_to_user(user_finfo, prog->aux->func_info, 3190 info.func_info_rec_size * ulen)) 3191 return -EFAULT; 3192 } 3193 3194 ulen = info.nr_line_info; 3195 info.nr_line_info = prog->aux->nr_linfo; 3196 if (info.nr_line_info && ulen) { 3197 __u8 __user *user_linfo; 3198 3199 user_linfo = u64_to_user_ptr(info.line_info); 3200 ulen = min_t(u32, info.nr_line_info, ulen); 3201 if (copy_to_user(user_linfo, prog->aux->linfo, 3202 info.line_info_rec_size * ulen)) 3203 return -EFAULT; 3204 } 3205 3206 ulen = info.nr_jited_line_info; 3207 if (prog->aux->jited_linfo) 3208 info.nr_jited_line_info = prog->aux->nr_linfo; 3209 else 3210 info.nr_jited_line_info = 0; 3211 if (info.nr_jited_line_info && ulen) { 3212 if (bpf_dump_raw_ok()) { 3213 __u64 __user *user_linfo; 3214 u32 i; 3215 3216 user_linfo = u64_to_user_ptr(info.jited_line_info); 3217 ulen = min_t(u32, info.nr_jited_line_info, ulen); 3218 for (i = 0; i < ulen; i++) { 3219 if (put_user((__u64)(long)prog->aux->jited_linfo[i], 3220 &user_linfo[i])) 3221 return -EFAULT; 3222 } 3223 } else { 3224 info.jited_line_info = 0; 3225 } 3226 } 3227 3228 ulen = info.nr_prog_tags; 3229 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 3230 if (ulen) { 3231 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 3232 u32 i; 3233 3234 user_prog_tags = u64_to_user_ptr(info.prog_tags); 3235 ulen = min_t(u32, info.nr_prog_tags, ulen); 3236 if (prog->aux->func_cnt) { 3237 for (i = 0; i < ulen; i++) { 3238 if (copy_to_user(user_prog_tags[i], 3239 prog->aux->func[i]->tag, 3240 BPF_TAG_SIZE)) 3241 return -EFAULT; 3242 } 3243 } else { 3244 if (copy_to_user(user_prog_tags[0], 3245 prog->tag, BPF_TAG_SIZE)) 3246 return -EFAULT; 3247 } 3248 } 3249 3250 done: 3251 if (copy_to_user(uinfo, &info, info_len) || 3252 put_user(info_len, &uattr->info.info_len)) 3253 return -EFAULT; 3254 3255 return 0; 3256 } 3257 3258 static int bpf_map_get_info_by_fd(struct bpf_map *map, 3259 const union bpf_attr *attr, 3260 union bpf_attr __user *uattr) 3261 { 3262 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3263 struct bpf_map_info info; 3264 u32 info_len = attr->info.info_len; 3265 int err; 3266 3267 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); 3268 if (err) 3269 return err; 3270 info_len = min_t(u32, sizeof(info), info_len); 3271 3272 memset(&info, 0, sizeof(info)); 3273 info.type = map->map_type; 3274 info.id = map->id; 3275 info.key_size = map->key_size; 3276 info.value_size = map->value_size; 3277 info.max_entries = map->max_entries; 3278 info.map_flags = map->map_flags; 3279 memcpy(info.name, map->name, sizeof(map->name)); 3280 3281 if (map->btf) { 3282 info.btf_id = btf_id(map->btf); 3283 info.btf_key_type_id = map->btf_key_type_id; 3284 info.btf_value_type_id = map->btf_value_type_id; 3285 } 3286 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 3287 3288 if (bpf_map_is_dev_bound(map)) { 3289 err = bpf_map_offload_info_fill(&info, map); 3290 if (err) 3291 return err; 3292 } 3293 3294 if (copy_to_user(uinfo, &info, info_len) || 3295 put_user(info_len, &uattr->info.info_len)) 3296 return -EFAULT; 3297 3298 return 0; 3299 } 3300 3301 static int bpf_btf_get_info_by_fd(struct btf *btf, 3302 const union bpf_attr *attr, 3303 union bpf_attr __user *uattr) 3304 { 3305 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 3306 u32 info_len = attr->info.info_len; 3307 int err; 3308 3309 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); 3310 if (err) 3311 return err; 3312 3313 return btf_get_info_by_fd(btf, attr, uattr); 3314 } 3315 3316 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 3317 3318 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 3319 union bpf_attr __user *uattr) 3320 { 3321 int ufd = attr->info.bpf_fd; 3322 struct fd f; 3323 int err; 3324 3325 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 3326 return -EINVAL; 3327 3328 f = fdget(ufd); 3329 if (!f.file) 3330 return -EBADFD; 3331 3332 if (f.file->f_op == &bpf_prog_fops) 3333 err = bpf_prog_get_info_by_fd(f.file->private_data, attr, 3334 uattr); 3335 else if (f.file->f_op == &bpf_map_fops) 3336 err = bpf_map_get_info_by_fd(f.file->private_data, attr, 3337 uattr); 3338 else if (f.file->f_op == &btf_fops) 3339 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr); 3340 else 3341 err = -EINVAL; 3342 3343 fdput(f); 3344 return err; 3345 } 3346 3347 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level 3348 3349 static int bpf_btf_load(const union bpf_attr *attr) 3350 { 3351 if (CHECK_ATTR(BPF_BTF_LOAD)) 3352 return -EINVAL; 3353 3354 if (!capable(CAP_SYS_ADMIN)) 3355 return -EPERM; 3356 3357 return btf_new_fd(attr); 3358 } 3359 3360 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 3361 3362 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 3363 { 3364 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 3365 return -EINVAL; 3366 3367 if (!capable(CAP_SYS_ADMIN)) 3368 return -EPERM; 3369 3370 return btf_get_fd_by_id(attr->btf_id); 3371 } 3372 3373 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 3374 union bpf_attr __user *uattr, 3375 u32 prog_id, u32 fd_type, 3376 const char *buf, u64 probe_offset, 3377 u64 probe_addr) 3378 { 3379 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 3380 u32 len = buf ? strlen(buf) : 0, input_len; 3381 int err = 0; 3382 3383 if (put_user(len, &uattr->task_fd_query.buf_len)) 3384 return -EFAULT; 3385 input_len = attr->task_fd_query.buf_len; 3386 if (input_len && ubuf) { 3387 if (!len) { 3388 /* nothing to copy, just make ubuf NULL terminated */ 3389 char zero = '\0'; 3390 3391 if (put_user(zero, ubuf)) 3392 return -EFAULT; 3393 } else if (input_len >= len + 1) { 3394 /* ubuf can hold the string with NULL terminator */ 3395 if (copy_to_user(ubuf, buf, len + 1)) 3396 return -EFAULT; 3397 } else { 3398 /* ubuf cannot hold the string with NULL terminator, 3399 * do a partial copy with NULL terminator. 3400 */ 3401 char zero = '\0'; 3402 3403 err = -ENOSPC; 3404 if (copy_to_user(ubuf, buf, input_len - 1)) 3405 return -EFAULT; 3406 if (put_user(zero, ubuf + input_len - 1)) 3407 return -EFAULT; 3408 } 3409 } 3410 3411 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 3412 put_user(fd_type, &uattr->task_fd_query.fd_type) || 3413 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 3414 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 3415 return -EFAULT; 3416 3417 return err; 3418 } 3419 3420 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 3421 3422 static int bpf_task_fd_query(const union bpf_attr *attr, 3423 union bpf_attr __user *uattr) 3424 { 3425 pid_t pid = attr->task_fd_query.pid; 3426 u32 fd = attr->task_fd_query.fd; 3427 const struct perf_event *event; 3428 struct files_struct *files; 3429 struct task_struct *task; 3430 struct file *file; 3431 int err; 3432 3433 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 3434 return -EINVAL; 3435 3436 if (!capable(CAP_SYS_ADMIN)) 3437 return -EPERM; 3438 3439 if (attr->task_fd_query.flags != 0) 3440 return -EINVAL; 3441 3442 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 3443 if (!task) 3444 return -ENOENT; 3445 3446 files = get_files_struct(task); 3447 put_task_struct(task); 3448 if (!files) 3449 return -ENOENT; 3450 3451 err = 0; 3452 spin_lock(&files->file_lock); 3453 file = fcheck_files(files, fd); 3454 if (!file) 3455 err = -EBADF; 3456 else 3457 get_file(file); 3458 spin_unlock(&files->file_lock); 3459 put_files_struct(files); 3460 3461 if (err) 3462 goto out; 3463 3464 if (file->f_op == &bpf_link_fops) { 3465 struct bpf_link *link = file->private_data; 3466 3467 if (link->ops == &bpf_raw_tp_lops) { 3468 struct bpf_raw_tp_link *raw_tp = 3469 container_of(link, struct bpf_raw_tp_link, link); 3470 struct bpf_raw_event_map *btp = raw_tp->btp; 3471 3472 err = bpf_task_fd_query_copy(attr, uattr, 3473 raw_tp->link.prog->aux->id, 3474 BPF_FD_TYPE_RAW_TRACEPOINT, 3475 btp->tp->name, 0, 0); 3476 goto put_file; 3477 } 3478 goto out_not_supp; 3479 } 3480 3481 event = perf_get_event(file); 3482 if (!IS_ERR(event)) { 3483 u64 probe_offset, probe_addr; 3484 u32 prog_id, fd_type; 3485 const char *buf; 3486 3487 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 3488 &buf, &probe_offset, 3489 &probe_addr); 3490 if (!err) 3491 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 3492 fd_type, buf, 3493 probe_offset, 3494 probe_addr); 3495 goto put_file; 3496 } 3497 3498 out_not_supp: 3499 err = -ENOTSUPP; 3500 put_file: 3501 fput(file); 3502 out: 3503 return err; 3504 } 3505 3506 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 3507 3508 #define BPF_DO_BATCH(fn) \ 3509 do { \ 3510 if (!fn) { \ 3511 err = -ENOTSUPP; \ 3512 goto err_put; \ 3513 } \ 3514 err = fn(map, attr, uattr); \ 3515 } while (0) 3516 3517 static int bpf_map_do_batch(const union bpf_attr *attr, 3518 union bpf_attr __user *uattr, 3519 int cmd) 3520 { 3521 struct bpf_map *map; 3522 int err, ufd; 3523 struct fd f; 3524 3525 if (CHECK_ATTR(BPF_MAP_BATCH)) 3526 return -EINVAL; 3527 3528 ufd = attr->batch.map_fd; 3529 f = fdget(ufd); 3530 map = __bpf_map_get(f); 3531 if (IS_ERR(map)) 3532 return PTR_ERR(map); 3533 3534 if ((cmd == BPF_MAP_LOOKUP_BATCH || 3535 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) && 3536 !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 3537 err = -EPERM; 3538 goto err_put; 3539 } 3540 3541 if (cmd != BPF_MAP_LOOKUP_BATCH && 3542 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 3543 err = -EPERM; 3544 goto err_put; 3545 } 3546 3547 if (cmd == BPF_MAP_LOOKUP_BATCH) 3548 BPF_DO_BATCH(map->ops->map_lookup_batch); 3549 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 3550 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); 3551 else if (cmd == BPF_MAP_UPDATE_BATCH) 3552 BPF_DO_BATCH(map->ops->map_update_batch); 3553 else 3554 BPF_DO_BATCH(map->ops->map_delete_batch); 3555 3556 err_put: 3557 fdput(f); 3558 return err; 3559 } 3560 3561 #define BPF_LINK_CREATE_LAST_FIELD link_create.flags 3562 static int link_create(union bpf_attr *attr) 3563 { 3564 enum bpf_prog_type ptype; 3565 struct bpf_prog *prog; 3566 int ret; 3567 3568 if (!capable(CAP_NET_ADMIN)) 3569 return -EPERM; 3570 3571 if (CHECK_ATTR(BPF_LINK_CREATE)) 3572 return -EINVAL; 3573 3574 ptype = attach_type_to_prog_type(attr->link_create.attach_type); 3575 if (ptype == BPF_PROG_TYPE_UNSPEC) 3576 return -EINVAL; 3577 3578 prog = bpf_prog_get_type(attr->link_create.prog_fd, ptype); 3579 if (IS_ERR(prog)) 3580 return PTR_ERR(prog); 3581 3582 ret = bpf_prog_attach_check_attach_type(prog, 3583 attr->link_create.attach_type); 3584 if (ret) 3585 goto err_out; 3586 3587 switch (ptype) { 3588 case BPF_PROG_TYPE_CGROUP_SKB: 3589 case BPF_PROG_TYPE_CGROUP_SOCK: 3590 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3591 case BPF_PROG_TYPE_SOCK_OPS: 3592 case BPF_PROG_TYPE_CGROUP_DEVICE: 3593 case BPF_PROG_TYPE_CGROUP_SYSCTL: 3594 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3595 ret = cgroup_bpf_link_attach(attr, prog); 3596 break; 3597 default: 3598 ret = -EINVAL; 3599 } 3600 3601 err_out: 3602 if (ret < 0) 3603 bpf_prog_put(prog); 3604 return ret; 3605 } 3606 3607 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 3608 3609 static int link_update(union bpf_attr *attr) 3610 { 3611 struct bpf_prog *old_prog = NULL, *new_prog; 3612 struct bpf_link *link; 3613 u32 flags; 3614 int ret; 3615 3616 if (!capable(CAP_NET_ADMIN)) 3617 return -EPERM; 3618 3619 if (CHECK_ATTR(BPF_LINK_UPDATE)) 3620 return -EINVAL; 3621 3622 flags = attr->link_update.flags; 3623 if (flags & ~BPF_F_REPLACE) 3624 return -EINVAL; 3625 3626 link = bpf_link_get_from_fd(attr->link_update.link_fd); 3627 if (IS_ERR(link)) 3628 return PTR_ERR(link); 3629 3630 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 3631 if (IS_ERR(new_prog)) { 3632 ret = PTR_ERR(new_prog); 3633 goto out_put_link; 3634 } 3635 3636 if (flags & BPF_F_REPLACE) { 3637 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 3638 if (IS_ERR(old_prog)) { 3639 ret = PTR_ERR(old_prog); 3640 old_prog = NULL; 3641 goto out_put_progs; 3642 } 3643 } else if (attr->link_update.old_prog_fd) { 3644 ret = -EINVAL; 3645 goto out_put_progs; 3646 } 3647 3648 #ifdef CONFIG_CGROUP_BPF 3649 if (link->ops == &bpf_cgroup_link_lops) { 3650 ret = cgroup_bpf_replace(link, old_prog, new_prog); 3651 goto out_put_progs; 3652 } 3653 #endif 3654 ret = -EINVAL; 3655 3656 out_put_progs: 3657 if (old_prog) 3658 bpf_prog_put(old_prog); 3659 if (ret) 3660 bpf_prog_put(new_prog); 3661 out_put_link: 3662 bpf_link_put(link); 3663 return ret; 3664 } 3665 3666 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 3667 { 3668 union bpf_attr attr; 3669 int err; 3670 3671 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) 3672 return -EPERM; 3673 3674 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 3675 if (err) 3676 return err; 3677 size = min_t(u32, size, sizeof(attr)); 3678 3679 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 3680 memset(&attr, 0, sizeof(attr)); 3681 if (copy_from_user(&attr, uattr, size) != 0) 3682 return -EFAULT; 3683 3684 err = security_bpf(cmd, &attr, size); 3685 if (err < 0) 3686 return err; 3687 3688 switch (cmd) { 3689 case BPF_MAP_CREATE: 3690 err = map_create(&attr); 3691 break; 3692 case BPF_MAP_LOOKUP_ELEM: 3693 err = map_lookup_elem(&attr); 3694 break; 3695 case BPF_MAP_UPDATE_ELEM: 3696 err = map_update_elem(&attr); 3697 break; 3698 case BPF_MAP_DELETE_ELEM: 3699 err = map_delete_elem(&attr); 3700 break; 3701 case BPF_MAP_GET_NEXT_KEY: 3702 err = map_get_next_key(&attr); 3703 break; 3704 case BPF_MAP_FREEZE: 3705 err = map_freeze(&attr); 3706 break; 3707 case BPF_PROG_LOAD: 3708 err = bpf_prog_load(&attr, uattr); 3709 break; 3710 case BPF_OBJ_PIN: 3711 err = bpf_obj_pin(&attr); 3712 break; 3713 case BPF_OBJ_GET: 3714 err = bpf_obj_get(&attr); 3715 break; 3716 case BPF_PROG_ATTACH: 3717 err = bpf_prog_attach(&attr); 3718 break; 3719 case BPF_PROG_DETACH: 3720 err = bpf_prog_detach(&attr); 3721 break; 3722 case BPF_PROG_QUERY: 3723 err = bpf_prog_query(&attr, uattr); 3724 break; 3725 case BPF_PROG_TEST_RUN: 3726 err = bpf_prog_test_run(&attr, uattr); 3727 break; 3728 case BPF_PROG_GET_NEXT_ID: 3729 err = bpf_obj_get_next_id(&attr, uattr, 3730 &prog_idr, &prog_idr_lock); 3731 break; 3732 case BPF_MAP_GET_NEXT_ID: 3733 err = bpf_obj_get_next_id(&attr, uattr, 3734 &map_idr, &map_idr_lock); 3735 break; 3736 case BPF_BTF_GET_NEXT_ID: 3737 err = bpf_obj_get_next_id(&attr, uattr, 3738 &btf_idr, &btf_idr_lock); 3739 break; 3740 case BPF_PROG_GET_FD_BY_ID: 3741 err = bpf_prog_get_fd_by_id(&attr); 3742 break; 3743 case BPF_MAP_GET_FD_BY_ID: 3744 err = bpf_map_get_fd_by_id(&attr); 3745 break; 3746 case BPF_OBJ_GET_INFO_BY_FD: 3747 err = bpf_obj_get_info_by_fd(&attr, uattr); 3748 break; 3749 case BPF_RAW_TRACEPOINT_OPEN: 3750 err = bpf_raw_tracepoint_open(&attr); 3751 break; 3752 case BPF_BTF_LOAD: 3753 err = bpf_btf_load(&attr); 3754 break; 3755 case BPF_BTF_GET_FD_BY_ID: 3756 err = bpf_btf_get_fd_by_id(&attr); 3757 break; 3758 case BPF_TASK_FD_QUERY: 3759 err = bpf_task_fd_query(&attr, uattr); 3760 break; 3761 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 3762 err = map_lookup_and_delete_elem(&attr); 3763 break; 3764 case BPF_MAP_LOOKUP_BATCH: 3765 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_LOOKUP_BATCH); 3766 break; 3767 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 3768 err = bpf_map_do_batch(&attr, uattr, 3769 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 3770 break; 3771 case BPF_MAP_UPDATE_BATCH: 3772 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_UPDATE_BATCH); 3773 break; 3774 case BPF_MAP_DELETE_BATCH: 3775 err = bpf_map_do_batch(&attr, uattr, BPF_MAP_DELETE_BATCH); 3776 break; 3777 case BPF_LINK_CREATE: 3778 err = link_create(&attr); 3779 break; 3780 case BPF_LINK_UPDATE: 3781 err = link_update(&attr); 3782 break; 3783 default: 3784 err = -EINVAL; 3785 break; 3786 } 3787 3788 return err; 3789 } 3790