1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <crypto/sha2.h> 5 #include <linux/bpf.h> 6 #include <linux/bpf-cgroup.h> 7 #include <linux/bpf_trace.h> 8 #include <linux/bpf_lirc.h> 9 #include <linux/bpf_verifier.h> 10 #include <linux/bsearch.h> 11 #include <linux/btf.h> 12 #include <linux/hex.h> 13 #include <linux/syscalls.h> 14 #include <linux/slab.h> 15 #include <linux/sched/signal.h> 16 #include <linux/vmalloc.h> 17 #include <linux/mmzone.h> 18 #include <linux/anon_inodes.h> 19 #include <linux/fdtable.h> 20 #include <linux/file.h> 21 #include <linux/fs.h> 22 #include <linux/license.h> 23 #include <linux/filter.h> 24 #include <linux/kernel.h> 25 #include <linux/idr.h> 26 #include <linux/cred.h> 27 #include <linux/timekeeping.h> 28 #include <linux/ctype.h> 29 #include <linux/nospec.h> 30 #include <linux/audit.h> 31 #include <uapi/linux/btf.h> 32 #include <linux/pgtable.h> 33 #include <linux/bpf_lsm.h> 34 #include <linux/poll.h> 35 #include <linux/sort.h> 36 #include <linux/bpf-netns.h> 37 #include <linux/rcupdate_trace.h> 38 #include <linux/memcontrol.h> 39 #include <linux/trace_events.h> 40 #include <linux/tracepoint.h> 41 #include <linux/overflow.h> 42 #include <linux/cookie.h> 43 #include <linux/btf_ids.h> 44 45 #include <net/netfilter/nf_bpf_link.h> 46 #include <net/netkit.h> 47 #include <net/tcx.h> 48 49 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 50 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 51 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 52 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 53 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 54 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 55 IS_FD_HASH(map)) 56 57 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 58 59 DEFINE_PER_CPU(int, bpf_prog_active); 60 DEFINE_COOKIE(bpf_map_cookie); 61 static DEFINE_IDR(prog_idr); 62 static DEFINE_SPINLOCK(prog_idr_lock); 63 static DEFINE_IDR(map_idr); 64 static DEFINE_SPINLOCK(map_idr_lock); 65 static DEFINE_IDR(link_idr); 66 static DEFINE_SPINLOCK(link_idr_lock); 67 68 int sysctl_unprivileged_bpf_disabled __read_mostly = 69 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 70 71 static const struct bpf_map_ops * const bpf_map_types[] = { 72 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 73 #define BPF_MAP_TYPE(_id, _ops) \ 74 [_id] = &_ops, 75 #define BPF_LINK_TYPE(_id, _name) 76 #include <linux/bpf_types.h> 77 #undef BPF_PROG_TYPE 78 #undef BPF_MAP_TYPE 79 #undef BPF_LINK_TYPE 80 }; 81 82 /* 83 * If we're handed a bigger struct than we know of, ensure all the unknown bits 84 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 85 * we don't know about yet. 86 * 87 * There is a ToCToU between this function call and the following 88 * copy_from_user() call. However, this is not a concern since this function is 89 * meant to be a future-proofing of bits. 90 */ 91 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 92 size_t expected_size, 93 size_t actual_size) 94 { 95 int res; 96 97 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 98 return -E2BIG; 99 100 if (actual_size <= expected_size) 101 return 0; 102 103 if (uaddr.is_kernel) 104 res = memchr_inv(uaddr.kernel + expected_size, 0, 105 actual_size - expected_size) == NULL; 106 else 107 res = check_zeroed_user(uaddr.user + expected_size, 108 actual_size - expected_size); 109 if (res < 0) 110 return res; 111 return res ? 0 : -E2BIG; 112 } 113 114 const struct bpf_map_ops bpf_map_offload_ops = { 115 .map_meta_equal = bpf_map_meta_equal, 116 .map_alloc = bpf_map_offload_map_alloc, 117 .map_free = bpf_map_offload_map_free, 118 .map_check_btf = map_check_no_btf, 119 .map_mem_usage = bpf_map_offload_map_mem_usage, 120 }; 121 122 static void bpf_map_write_active_inc(struct bpf_map *map) 123 { 124 atomic64_inc(&map->writecnt); 125 } 126 127 static void bpf_map_write_active_dec(struct bpf_map *map) 128 { 129 atomic64_dec(&map->writecnt); 130 } 131 132 bool bpf_map_write_active(const struct bpf_map *map) 133 { 134 return atomic64_read(&map->writecnt) != 0; 135 } 136 137 static u32 bpf_map_value_size(const struct bpf_map *map, u64 flags) 138 { 139 if (flags & (BPF_F_CPU | BPF_F_ALL_CPUS)) 140 return map->value_size; 141 else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 142 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 143 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 144 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 145 return round_up(map->value_size, 8) * num_possible_cpus(); 146 else if (IS_FD_MAP(map)) 147 return sizeof(u32); 148 else 149 return map->value_size; 150 } 151 152 static void maybe_wait_bpf_programs(struct bpf_map *map) 153 { 154 /* Wait for any running non-sleepable BPF programs to complete so that 155 * userspace, when we return to it, knows that all non-sleepable 156 * programs that could be running use the new map value. For sleepable 157 * BPF programs, synchronize_rcu_tasks_trace() should be used to wait 158 * for the completions of these programs, but considering the waiting 159 * time can be very long and userspace may think it will hang forever, 160 * so don't handle sleepable BPF programs now. 161 */ 162 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 163 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 164 synchronize_rcu_expedited(); 165 } 166 167 static void unpin_uptr_kaddr(void *kaddr) 168 { 169 if (kaddr) 170 unpin_user_page(virt_to_page(kaddr)); 171 } 172 173 static void __bpf_obj_unpin_uptrs(struct btf_record *rec, u32 cnt, void *obj) 174 { 175 const struct btf_field *field; 176 void **uptr_addr; 177 int i; 178 179 for (i = 0, field = rec->fields; i < cnt; i++, field++) { 180 if (field->type != BPF_UPTR) 181 continue; 182 183 uptr_addr = obj + field->offset; 184 unpin_uptr_kaddr(*uptr_addr); 185 } 186 } 187 188 static void bpf_obj_unpin_uptrs(struct btf_record *rec, void *obj) 189 { 190 if (!btf_record_has_field(rec, BPF_UPTR)) 191 return; 192 193 __bpf_obj_unpin_uptrs(rec, rec->cnt, obj); 194 } 195 196 static int bpf_obj_pin_uptrs(struct btf_record *rec, void *obj) 197 { 198 const struct btf_field *field; 199 const struct btf_type *t; 200 unsigned long start, end; 201 struct page *page; 202 void **uptr_addr; 203 int i, err; 204 205 if (!btf_record_has_field(rec, BPF_UPTR)) 206 return 0; 207 208 for (i = 0, field = rec->fields; i < rec->cnt; i++, field++) { 209 if (field->type != BPF_UPTR) 210 continue; 211 212 uptr_addr = obj + field->offset; 213 start = *(unsigned long *)uptr_addr; 214 if (!start) 215 continue; 216 217 t = btf_type_by_id(field->kptr.btf, field->kptr.btf_id); 218 /* t->size was checked for zero before */ 219 if (check_add_overflow(start, t->size - 1, &end)) { 220 err = -EFAULT; 221 goto unpin_all; 222 } 223 224 /* The uptr's struct cannot span across two pages */ 225 if ((start & PAGE_MASK) != (end & PAGE_MASK)) { 226 err = -EOPNOTSUPP; 227 goto unpin_all; 228 } 229 230 err = pin_user_pages_fast(start, 1, FOLL_LONGTERM | FOLL_WRITE, &page); 231 if (err != 1) 232 goto unpin_all; 233 234 if (PageHighMem(page)) { 235 err = -EOPNOTSUPP; 236 unpin_user_page(page); 237 goto unpin_all; 238 } 239 240 *uptr_addr = page_address(page) + offset_in_page(start); 241 } 242 243 return 0; 244 245 unpin_all: 246 __bpf_obj_unpin_uptrs(rec, i, obj); 247 return err; 248 } 249 250 static int bpf_map_update_value(struct bpf_map *map, struct file *map_file, 251 void *key, void *value, __u64 flags) 252 { 253 int err; 254 255 /* Need to create a kthread, thus must support schedule */ 256 if (bpf_map_is_offloaded(map)) { 257 return bpf_map_offload_update_elem(map, key, value, flags); 258 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 259 map->map_type == BPF_MAP_TYPE_ARENA || 260 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 261 return map->ops->map_update_elem(map, key, value, flags); 262 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 263 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 264 return sock_map_update_elem_sys(map, key, value, flags); 265 } else if (IS_FD_PROG_ARRAY(map)) { 266 return bpf_fd_array_map_update_elem(map, map_file, key, value, 267 flags); 268 } 269 270 bpf_disable_instrumentation(); 271 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 272 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 273 err = bpf_percpu_hash_update(map, key, value, flags); 274 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 275 err = bpf_percpu_array_update(map, key, value, flags); 276 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 277 err = bpf_percpu_cgroup_storage_update(map, key, value, 278 flags); 279 } else if (IS_FD_ARRAY(map)) { 280 err = bpf_fd_array_map_update_elem(map, map_file, key, value, 281 flags); 282 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 283 err = bpf_fd_htab_map_update_elem(map, map_file, key, value, 284 flags); 285 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 286 /* rcu_read_lock() is not needed */ 287 err = bpf_fd_reuseport_array_update_elem(map, key, value, 288 flags); 289 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 290 map->map_type == BPF_MAP_TYPE_STACK || 291 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 292 err = map->ops->map_push_elem(map, value, flags); 293 } else { 294 err = bpf_obj_pin_uptrs(map->record, value); 295 if (!err) { 296 rcu_read_lock(); 297 err = map->ops->map_update_elem(map, key, value, flags); 298 rcu_read_unlock(); 299 if (err) 300 bpf_obj_unpin_uptrs(map->record, value); 301 } 302 } 303 bpf_enable_instrumentation(); 304 305 return err; 306 } 307 308 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 309 __u64 flags) 310 { 311 void *ptr; 312 int err; 313 314 if (bpf_map_is_offloaded(map)) 315 return bpf_map_offload_lookup_elem(map, key, value); 316 317 bpf_disable_instrumentation(); 318 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 319 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 320 err = bpf_percpu_hash_copy(map, key, value, flags); 321 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 322 err = bpf_percpu_array_copy(map, key, value, flags); 323 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 324 err = bpf_percpu_cgroup_storage_copy(map, key, value, flags); 325 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 326 err = bpf_stackmap_extract(map, key, value, false); 327 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 328 err = bpf_fd_array_map_lookup_elem(map, key, value); 329 } else if (IS_FD_HASH(map)) { 330 err = bpf_fd_htab_map_lookup_elem(map, key, value); 331 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 332 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 333 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 334 map->map_type == BPF_MAP_TYPE_STACK || 335 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 336 err = map->ops->map_peek_elem(map, value); 337 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 338 /* struct_ops map requires directly updating "value" */ 339 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 340 } else { 341 rcu_read_lock(); 342 if (map->ops->map_lookup_elem_sys_only) 343 ptr = map->ops->map_lookup_elem_sys_only(map, key); 344 else 345 ptr = map->ops->map_lookup_elem(map, key); 346 if (IS_ERR(ptr)) { 347 err = PTR_ERR(ptr); 348 } else if (!ptr) { 349 err = -ENOENT; 350 } else { 351 err = 0; 352 if (flags & BPF_F_LOCK) 353 /* lock 'ptr' and copy everything but lock */ 354 copy_map_value_locked(map, value, ptr, true); 355 else 356 copy_map_value(map, value, ptr); 357 /* mask lock and timer, since value wasn't zero inited */ 358 check_and_init_map_value(map, value); 359 } 360 rcu_read_unlock(); 361 } 362 363 bpf_enable_instrumentation(); 364 365 return err; 366 } 367 368 /* Please, do not use this function outside from the map creation path 369 * (e.g. in map update path) without taking care of setting the active 370 * memory cgroup (see at bpf_map_kmalloc_node() for example). 371 */ 372 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 373 { 374 /* We really just want to fail instead of triggering OOM killer 375 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 376 * which is used for lower order allocation requests. 377 * 378 * It has been observed that higher order allocation requests done by 379 * vmalloc with __GFP_NORETRY being set might fail due to not trying 380 * to reclaim memory from the page cache, thus we set 381 * __GFP_RETRY_MAYFAIL to avoid such situations. 382 */ 383 384 gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO); 385 unsigned int flags = 0; 386 unsigned long align = 1; 387 void *area; 388 389 if (size >= SIZE_MAX) 390 return NULL; 391 392 /* kmalloc()'ed memory can't be mmap()'ed */ 393 if (mmapable) { 394 BUG_ON(!PAGE_ALIGNED(size)); 395 align = SHMLBA; 396 flags = VM_USERMAP; 397 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 398 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 399 numa_node); 400 if (area != NULL) 401 return area; 402 } 403 404 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 405 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 406 flags, numa_node, __builtin_return_address(0)); 407 } 408 409 void *bpf_map_area_alloc(u64 size, int numa_node) 410 { 411 return __bpf_map_area_alloc(size, numa_node, false); 412 } 413 414 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 415 { 416 return __bpf_map_area_alloc(size, numa_node, true); 417 } 418 419 void bpf_map_area_free(void *area) 420 { 421 kvfree(area); 422 } 423 424 static u32 bpf_map_flags_retain_permanent(u32 flags) 425 { 426 /* Some map creation flags are not tied to the map object but 427 * rather to the map fd instead, so they have no meaning upon 428 * map object inspection since multiple file descriptors with 429 * different (access) properties can exist here. Thus, given 430 * this has zero meaning for the map itself, lets clear these 431 * from here. 432 */ 433 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 434 } 435 436 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 437 { 438 map->map_type = attr->map_type; 439 map->key_size = attr->key_size; 440 map->value_size = attr->value_size; 441 map->max_entries = attr->max_entries; 442 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 443 map->numa_node = bpf_map_attr_numa_node(attr); 444 map->map_extra = attr->map_extra; 445 } 446 447 static int bpf_map_alloc_id(struct bpf_map *map) 448 { 449 int id; 450 451 idr_preload(GFP_KERNEL); 452 spin_lock_bh(&map_idr_lock); 453 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 454 if (id > 0) 455 map->id = id; 456 spin_unlock_bh(&map_idr_lock); 457 idr_preload_end(); 458 459 if (WARN_ON_ONCE(!id)) 460 return -ENOSPC; 461 462 return id > 0 ? 0 : id; 463 } 464 465 void bpf_map_free_id(struct bpf_map *map) 466 { 467 unsigned long flags; 468 469 /* Offloaded maps are removed from the IDR store when their device 470 * disappears - even if someone holds an fd to them they are unusable, 471 * the memory is gone, all ops will fail; they are simply waiting for 472 * refcnt to drop to be freed. 473 */ 474 if (!map->id) 475 return; 476 477 spin_lock_irqsave(&map_idr_lock, flags); 478 479 idr_remove(&map_idr, map->id); 480 map->id = 0; 481 482 spin_unlock_irqrestore(&map_idr_lock, flags); 483 } 484 485 #ifdef CONFIG_MEMCG 486 static void bpf_map_save_memcg(struct bpf_map *map) 487 { 488 /* Currently if a map is created by a process belonging to the root 489 * memory cgroup, get_obj_cgroup_from_current() will return NULL. 490 * So we have to check map->objcg for being NULL each time it's 491 * being used. 492 */ 493 if (memcg_bpf_enabled()) 494 map->objcg = get_obj_cgroup_from_current(); 495 } 496 497 static void bpf_map_release_memcg(struct bpf_map *map) 498 { 499 if (map->objcg) 500 obj_cgroup_put(map->objcg); 501 } 502 503 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map) 504 { 505 if (map->objcg) 506 return get_mem_cgroup_from_objcg(map->objcg); 507 508 return root_mem_cgroup; 509 } 510 511 void bpf_map_memcg_enter(const struct bpf_map *map, struct mem_cgroup **old_memcg, 512 struct mem_cgroup **new_memcg) 513 { 514 *new_memcg = bpf_map_get_memcg(map); 515 *old_memcg = set_active_memcg(*new_memcg); 516 } 517 518 void bpf_map_memcg_exit(struct mem_cgroup *old_memcg, 519 struct mem_cgroup *new_memcg) 520 { 521 set_active_memcg(old_memcg); 522 mem_cgroup_put(new_memcg); 523 } 524 525 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 526 int node) 527 { 528 struct mem_cgroup *memcg, *old_memcg; 529 void *ptr; 530 531 bpf_map_memcg_enter(map, &old_memcg, &memcg); 532 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 533 bpf_map_memcg_exit(old_memcg, memcg); 534 535 return ptr; 536 } 537 538 void *bpf_map_kmalloc_nolock(const struct bpf_map *map, size_t size, gfp_t flags, 539 int node) 540 { 541 struct mem_cgroup *memcg, *old_memcg; 542 void *ptr; 543 544 bpf_map_memcg_enter(map, &old_memcg, &memcg); 545 ptr = kmalloc_nolock(size, flags | __GFP_ACCOUNT, node); 546 bpf_map_memcg_exit(old_memcg, memcg); 547 548 return ptr; 549 } 550 551 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 552 { 553 struct mem_cgroup *memcg, *old_memcg; 554 void *ptr; 555 556 bpf_map_memcg_enter(map, &old_memcg, &memcg); 557 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 558 bpf_map_memcg_exit(old_memcg, memcg); 559 560 return ptr; 561 } 562 563 void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size, 564 gfp_t flags) 565 { 566 struct mem_cgroup *memcg, *old_memcg; 567 void *ptr; 568 569 bpf_map_memcg_enter(map, &old_memcg, &memcg); 570 ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT); 571 bpf_map_memcg_exit(old_memcg, memcg); 572 573 return ptr; 574 } 575 576 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 577 size_t align, gfp_t flags) 578 { 579 struct mem_cgroup *memcg, *old_memcg; 580 void __percpu *ptr; 581 582 bpf_map_memcg_enter(map, &old_memcg, &memcg); 583 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 584 bpf_map_memcg_exit(old_memcg, memcg); 585 586 return ptr; 587 } 588 589 #else 590 static void bpf_map_save_memcg(struct bpf_map *map) 591 { 592 } 593 594 static void bpf_map_release_memcg(struct bpf_map *map) 595 { 596 } 597 #endif 598 599 static bool can_alloc_pages(void) 600 { 601 return preempt_count() == 0 && !irqs_disabled() && 602 !IS_ENABLED(CONFIG_PREEMPT_RT); 603 } 604 605 struct page *bpf_alloc_page(int nid, bool sleepable) 606 { 607 if (!sleepable || !can_alloc_pages()) 608 return alloc_pages_nolock(__GFP_ACCOUNT, nid, 0); 609 610 return alloc_pages_node(nid, 611 GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT 612 | __GFP_NOWARN | __GFP_RETRY_MAYFAIL, 613 0); 614 } 615 616 void bpf_free_pages(struct llist_head *pages) 617 { 618 struct llist_node *node; 619 struct page *page, *tmp; 620 621 node = llist_del_all(pages); 622 llist_for_each_entry_safe(page, tmp, node, pcp_llist) 623 free_pages_nolock(page, 0); 624 } 625 626 int bpf_alloc_pages(int nid, unsigned long nr_pages, 627 struct llist_head *pages, bool sleepable) 628 { 629 unsigned long i; 630 struct page *pg; 631 632 for (i = 0; i < nr_pages; i++) { 633 pg = bpf_alloc_page(nid, sleepable); 634 if (!pg) 635 goto free_pages; 636 llist_add(&pg->pcp_llist, pages); 637 } 638 639 return 0; 640 641 free_pages: 642 bpf_free_pages(pages); 643 return -ENOMEM; 644 } 645 646 static int btf_field_cmp(const void *a, const void *b) 647 { 648 const struct btf_field *f1 = a, *f2 = b; 649 650 if (f1->offset < f2->offset) 651 return -1; 652 else if (f1->offset > f2->offset) 653 return 1; 654 return 0; 655 } 656 657 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, 658 u32 field_mask) 659 { 660 struct btf_field *field; 661 662 if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask)) 663 return NULL; 664 field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); 665 if (!field || !(field->type & field_mask)) 666 return NULL; 667 return field; 668 } 669 670 void btf_record_free(struct btf_record *rec) 671 { 672 int i; 673 674 if (IS_ERR_OR_NULL(rec)) 675 return; 676 for (i = 0; i < rec->cnt; i++) { 677 switch (rec->fields[i].type) { 678 case BPF_KPTR_UNREF: 679 case BPF_KPTR_REF: 680 case BPF_KPTR_PERCPU: 681 case BPF_UPTR: 682 if (rec->fields[i].kptr.module) 683 module_put(rec->fields[i].kptr.module); 684 if (btf_is_kernel(rec->fields[i].kptr.btf)) 685 btf_put(rec->fields[i].kptr.btf); 686 break; 687 case BPF_LIST_HEAD: 688 case BPF_LIST_NODE: 689 case BPF_RB_ROOT: 690 case BPF_RB_NODE: 691 case BPF_SPIN_LOCK: 692 case BPF_RES_SPIN_LOCK: 693 case BPF_TIMER: 694 case BPF_REFCOUNT: 695 case BPF_WORKQUEUE: 696 case BPF_TASK_WORK: 697 case BPF_RCU_HEAD: 698 /* Nothing to release */ 699 break; 700 default: 701 WARN_ON_ONCE(1); 702 continue; 703 } 704 } 705 kfree(rec); 706 } 707 708 void bpf_map_free_record(struct bpf_map *map) 709 { 710 btf_record_free(map->record); 711 map->record = NULL; 712 } 713 714 struct btf_record *btf_record_dup(const struct btf_record *rec) 715 { 716 const struct btf_field *fields; 717 struct btf_record *new_rec; 718 int ret, size, i; 719 720 if (IS_ERR_OR_NULL(rec)) 721 return NULL; 722 size = struct_size(rec, fields, rec->cnt); 723 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); 724 if (!new_rec) 725 return ERR_PTR(-ENOMEM); 726 /* Do a deep copy of the btf_record */ 727 fields = rec->fields; 728 new_rec->cnt = 0; 729 for (i = 0; i < rec->cnt; i++) { 730 switch (fields[i].type) { 731 case BPF_KPTR_UNREF: 732 case BPF_KPTR_REF: 733 case BPF_KPTR_PERCPU: 734 case BPF_UPTR: 735 if (btf_is_kernel(fields[i].kptr.btf)) 736 btf_get(fields[i].kptr.btf); 737 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { 738 ret = -ENXIO; 739 goto free; 740 } 741 break; 742 case BPF_LIST_HEAD: 743 case BPF_LIST_NODE: 744 case BPF_RB_ROOT: 745 case BPF_RB_NODE: 746 case BPF_SPIN_LOCK: 747 case BPF_RES_SPIN_LOCK: 748 case BPF_TIMER: 749 case BPF_REFCOUNT: 750 case BPF_WORKQUEUE: 751 case BPF_TASK_WORK: 752 case BPF_RCU_HEAD: 753 /* Nothing to acquire */ 754 break; 755 default: 756 ret = -EFAULT; 757 WARN_ON_ONCE(1); 758 goto free; 759 } 760 new_rec->cnt++; 761 } 762 return new_rec; 763 free: 764 btf_record_free(new_rec); 765 return ERR_PTR(ret); 766 } 767 768 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) 769 { 770 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); 771 int size; 772 773 if (!a_has_fields && !b_has_fields) 774 return true; 775 if (a_has_fields != b_has_fields) 776 return false; 777 if (rec_a->cnt != rec_b->cnt) 778 return false; 779 size = struct_size(rec_a, fields, rec_a->cnt); 780 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused 781 * members are zeroed out. So memcmp is safe to do without worrying 782 * about padding/unused fields. 783 * 784 * While spin_lock, timer, and kptr have no relation to map BTF, 785 * list_head metadata is specific to map BTF, the btf and value_rec 786 * members in particular. btf is the map BTF, while value_rec points to 787 * btf_record in that map BTF. 788 * 789 * So while by default, we don't rely on the map BTF (which the records 790 * were parsed from) matching for both records, which is not backwards 791 * compatible, in case list_head is part of it, we implicitly rely on 792 * that by way of depending on memcmp succeeding for it. 793 */ 794 return !memcmp(rec_a, rec_b, size); 795 } 796 797 void bpf_obj_free_timer(const struct btf_record *rec, void *obj) 798 { 799 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) 800 return; 801 bpf_timer_cancel_and_free(obj + rec->timer_off); 802 } 803 804 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj) 805 { 806 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE))) 807 return; 808 bpf_wq_cancel_and_free(obj + rec->wq_off); 809 } 810 811 void bpf_obj_free_task_work(const struct btf_record *rec, void *obj) 812 { 813 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TASK_WORK))) 814 return; 815 bpf_task_work_cancel_and_free(obj + rec->task_work_off); 816 } 817 818 void bpf_obj_cancel_fields(struct bpf_map *map, void *obj) 819 { 820 bpf_map_free_internal_structs(map, obj); 821 } 822 823 void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 824 { 825 const struct btf_field *fields; 826 int i; 827 828 if (IS_ERR_OR_NULL(rec)) 829 return; 830 fields = rec->fields; 831 for (i = 0; i < rec->cnt; i++) { 832 struct btf_struct_meta *pointee_struct_meta; 833 const struct btf_field *field = &fields[i]; 834 void *field_ptr = obj + field->offset; 835 void *xchgd_field; 836 837 switch (fields[i].type) { 838 case BPF_SPIN_LOCK: 839 case BPF_RES_SPIN_LOCK: 840 break; 841 case BPF_TIMER: 842 bpf_timer_cancel_and_free(field_ptr); 843 break; 844 case BPF_WORKQUEUE: 845 bpf_wq_cancel_and_free(field_ptr); 846 break; 847 case BPF_TASK_WORK: 848 bpf_task_work_cancel_and_free(field_ptr); 849 break; 850 case BPF_KPTR_UNREF: 851 WRITE_ONCE(*(u64 *)field_ptr, 0); 852 break; 853 case BPF_KPTR_REF: 854 case BPF_KPTR_PERCPU: 855 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); 856 if (!xchgd_field) 857 break; 858 859 if (!btf_is_kernel(field->kptr.btf)) { 860 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, 861 field->kptr.btf_id); 862 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? 863 pointee_struct_meta->record : NULL, 864 fields[i].type == BPF_KPTR_PERCPU); 865 } else { 866 field->kptr.dtor(xchgd_field); 867 } 868 break; 869 case BPF_UPTR: 870 /* The caller ensured that no one is using the uptr */ 871 unpin_uptr_kaddr(*(void **)field_ptr); 872 break; 873 case BPF_LIST_HEAD: 874 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 875 continue; 876 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); 877 break; 878 case BPF_RB_ROOT: 879 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 880 continue; 881 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); 882 break; 883 case BPF_LIST_NODE: 884 case BPF_RB_NODE: 885 case BPF_REFCOUNT: 886 case BPF_RCU_HEAD: 887 break; 888 default: 889 WARN_ON_ONCE(1); 890 continue; 891 } 892 } 893 } 894 895 static void bpf_map_free(struct bpf_map *map) 896 { 897 struct btf_record *rec = map->record; 898 struct btf *btf = map->btf; 899 900 /* implementation dependent freeing. Disabling migration to simplify 901 * the free of values or special fields allocated from bpf memory 902 * allocator. 903 */ 904 kfree(map->excl_prog_sha); 905 migrate_disable(); 906 map->ops->map_free(map); 907 migrate_enable(); 908 909 /* Delay freeing of btf_record for maps, as map_free 910 * callback usually needs access to them. It is better to do it here 911 * than require each callback to do the free itself manually. 912 * 913 * Note that the btf_record stashed in map->inner_map_meta->record was 914 * already freed using the map_free callback for map in map case which 915 * eventually calls bpf_map_free_meta, since inner_map_meta is only a 916 * template bpf_map struct used during verification. 917 */ 918 btf_record_free(rec); 919 /* Delay freeing of btf for maps, as map_free callback may need 920 * struct_meta info which will be freed with btf_put(). 921 */ 922 btf_put(btf); 923 } 924 925 /* called from workqueue */ 926 static void bpf_map_free_deferred(struct work_struct *work) 927 { 928 struct bpf_map *map = container_of(work, struct bpf_map, work); 929 930 security_bpf_map_free(map); 931 bpf_map_release_memcg(map); 932 bpf_map_owner_free(map); 933 bpf_map_free(map); 934 } 935 936 static void bpf_map_put_uref(struct bpf_map *map) 937 { 938 if (atomic64_dec_and_test(&map->usercnt)) { 939 if (map->ops->map_release_uref) 940 map->ops->map_release_uref(map); 941 } 942 } 943 944 static void bpf_map_free_in_work(struct bpf_map *map) 945 { 946 INIT_WORK(&map->work, bpf_map_free_deferred); 947 /* Avoid spawning kworkers, since they all might contend 948 * for the same mutex like slab_mutex. 949 */ 950 queue_work(system_dfl_wq, &map->work); 951 } 952 953 static void bpf_map_free_rcu_gp(struct rcu_head *rcu) 954 { 955 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); 956 } 957 958 /* decrement map refcnt and schedule it for freeing via workqueue 959 * (underlying map implementation ops->map_free() might sleep) 960 */ 961 void bpf_map_put(struct bpf_map *map) 962 { 963 if (atomic64_dec_and_test(&map->refcnt)) { 964 /* bpf_map_free_id() must be called first */ 965 bpf_map_free_id(map); 966 967 if (map->ops->map_free_pre_rcu) 968 map->ops->map_free_pre_rcu(map); 969 970 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); 971 /* RCU tasks trace grace period implies RCU grace period. */ 972 if (READ_ONCE(map->free_after_mult_rcu_gp)) 973 call_rcu_tasks_trace(&map->rcu, bpf_map_free_rcu_gp); 974 else if (READ_ONCE(map->free_after_rcu_gp)) 975 call_rcu(&map->rcu, bpf_map_free_rcu_gp); 976 else 977 bpf_map_free_in_work(map); 978 } 979 } 980 EXPORT_SYMBOL_GPL(bpf_map_put); 981 982 void bpf_map_put_with_uref(struct bpf_map *map) 983 { 984 bpf_map_put_uref(map); 985 bpf_map_put(map); 986 } 987 988 static int bpf_map_release(struct inode *inode, struct file *filp) 989 { 990 struct bpf_map *map = filp->private_data; 991 992 if (map->ops->map_release) 993 map->ops->map_release(map, filp); 994 995 bpf_map_put_with_uref(map); 996 return 0; 997 } 998 999 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 1000 { 1001 fmode_t mode = fd_file(f)->f_mode; 1002 1003 /* Our file permissions may have been overridden by global 1004 * map permissions facing syscall side. 1005 */ 1006 if (READ_ONCE(map->frozen)) 1007 mode &= ~FMODE_CAN_WRITE; 1008 return mode; 1009 } 1010 1011 #ifdef CONFIG_PROC_FS 1012 /* Show the memory usage of a bpf map */ 1013 static u64 bpf_map_memory_usage(const struct bpf_map *map) 1014 { 1015 return map->ops->map_mem_usage(map); 1016 } 1017 1018 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 1019 { 1020 struct bpf_map *map = filp->private_data; 1021 u32 type = 0, jited = 0; 1022 1023 spin_lock(&map->owner_lock); 1024 if (map->owner) { 1025 type = map->owner->type; 1026 jited = map->owner->jited; 1027 } 1028 spin_unlock(&map->owner_lock); 1029 1030 seq_printf(m, 1031 "map_type:\t%u\n" 1032 "key_size:\t%u\n" 1033 "value_size:\t%u\n" 1034 "max_entries:\t%u\n" 1035 "map_flags:\t%#x\n" 1036 "map_extra:\t%#llx\n" 1037 "memlock:\t%llu\n" 1038 "map_id:\t%u\n" 1039 "frozen:\t%u\n", 1040 map->map_type, 1041 map->key_size, 1042 map->value_size, 1043 map->max_entries, 1044 map->map_flags, 1045 (unsigned long long)map->map_extra, 1046 bpf_map_memory_usage(map), 1047 map->id, 1048 READ_ONCE(map->frozen)); 1049 if (type) { 1050 seq_printf(m, "owner_prog_type:\t%u\n", type); 1051 seq_printf(m, "owner_jited:\t%u\n", jited); 1052 } 1053 } 1054 #endif 1055 1056 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 1057 loff_t *ppos) 1058 { 1059 /* We need this handler such that alloc_file() enables 1060 * f_mode with FMODE_CAN_READ. 1061 */ 1062 return -EINVAL; 1063 } 1064 1065 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 1066 size_t siz, loff_t *ppos) 1067 { 1068 /* We need this handler such that alloc_file() enables 1069 * f_mode with FMODE_CAN_WRITE. 1070 */ 1071 return -EINVAL; 1072 } 1073 1074 /* called for any extra memory-mapped regions (except initial) */ 1075 static void bpf_map_mmap_open(struct vm_area_struct *vma) 1076 { 1077 struct bpf_map *map = vma->vm_file->private_data; 1078 1079 if (vma->vm_flags & VM_MAYWRITE) 1080 bpf_map_write_active_inc(map); 1081 } 1082 1083 /* called for all unmapped memory region (including initial) */ 1084 static void bpf_map_mmap_close(struct vm_area_struct *vma) 1085 { 1086 struct bpf_map *map = vma->vm_file->private_data; 1087 1088 if (vma->vm_flags & VM_MAYWRITE) 1089 bpf_map_write_active_dec(map); 1090 } 1091 1092 static vm_fault_t bpf_map_mmap_fault(struct vm_fault *vmf) 1093 { 1094 struct bpf_map *map = vmf->vma->vm_private_data; 1095 1096 return map->ops->map_mmap_fault(map, vmf); 1097 } 1098 1099 static const struct vm_operations_struct bpf_map_default_vmops = { 1100 .open = bpf_map_mmap_open, 1101 .close = bpf_map_mmap_close, 1102 }; 1103 1104 static const struct vm_operations_struct bpf_map_lazy_vmops = { 1105 .open = bpf_map_mmap_open, 1106 .close = bpf_map_mmap_close, 1107 .fault = bpf_map_mmap_fault, 1108 }; 1109 1110 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 1111 { 1112 struct bpf_map *map = filp->private_data; 1113 int err = 0; 1114 1115 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) 1116 return -ENOTSUPP; 1117 1118 if (!(vma->vm_flags & VM_SHARED)) 1119 return -EINVAL; 1120 1121 mutex_lock(&map->freeze_mutex); 1122 1123 if (vma->vm_flags & VM_WRITE) { 1124 if (map->frozen) { 1125 err = -EPERM; 1126 goto out; 1127 } 1128 /* map is meant to be read-only, so do not allow mapping as 1129 * writable, because it's possible to leak a writable page 1130 * reference and allows user-space to still modify it after 1131 * freezing, while verifier will assume contents do not change 1132 */ 1133 if (map->map_flags & BPF_F_RDONLY_PROG) { 1134 err = -EACCES; 1135 goto out; 1136 } 1137 bpf_map_write_active_inc(map); 1138 } 1139 out: 1140 mutex_unlock(&map->freeze_mutex); 1141 if (err) 1142 return err; 1143 1144 /* set default open/close callbacks */ 1145 vma->vm_ops = map->ops->map_mmap_fault ? &bpf_map_lazy_vmops : &bpf_map_default_vmops; 1146 vma->vm_private_data = map; 1147 vm_flags_clear(vma, VM_MAYEXEC); 1148 /* If mapping is read-only, then disallow potentially re-mapping with 1149 * PROT_WRITE by dropping VM_MAYWRITE flag. This VM_MAYWRITE clearing 1150 * means that as far as BPF map's memory-mapped VMAs are concerned, 1151 * VM_WRITE and VM_MAYWRITE and equivalent, if one of them is set, 1152 * both should be set, so we can forget about VM_MAYWRITE and always 1153 * check just VM_WRITE 1154 */ 1155 if (!(vma->vm_flags & VM_WRITE)) 1156 vm_flags_clear(vma, VM_MAYWRITE); 1157 1158 err = map->ops->map_mmap(map, vma); 1159 if (err) { 1160 if (vma->vm_flags & VM_WRITE) 1161 bpf_map_write_active_dec(map); 1162 } 1163 1164 return err; 1165 } 1166 1167 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 1168 { 1169 struct bpf_map *map = filp->private_data; 1170 1171 if (map->ops->map_poll) 1172 return map->ops->map_poll(map, filp, pts); 1173 1174 return EPOLLERR; 1175 } 1176 1177 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, 1178 unsigned long len, unsigned long pgoff, 1179 unsigned long flags) 1180 { 1181 struct bpf_map *map = filp->private_data; 1182 1183 if (map->ops->map_get_unmapped_area) 1184 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); 1185 #ifdef CONFIG_MMU 1186 return mm_get_unmapped_area(filp, addr, len, pgoff, flags); 1187 #else 1188 return addr; 1189 #endif 1190 } 1191 1192 const struct file_operations bpf_map_fops = { 1193 #ifdef CONFIG_PROC_FS 1194 .show_fdinfo = bpf_map_show_fdinfo, 1195 #endif 1196 .release = bpf_map_release, 1197 .read = bpf_dummy_read, 1198 .write = bpf_dummy_write, 1199 .mmap = bpf_map_mmap, 1200 .poll = bpf_map_poll, 1201 .get_unmapped_area = bpf_get_unmapped_area, 1202 }; 1203 1204 int bpf_map_new_fd(struct bpf_map *map, int flags) 1205 { 1206 int ret; 1207 1208 ret = security_bpf_map(map, OPEN_FMODE(flags)); 1209 if (ret < 0) 1210 return ret; 1211 1212 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 1213 flags | O_CLOEXEC); 1214 } 1215 1216 int bpf_get_file_flag(int flags) 1217 { 1218 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 1219 return -EINVAL; 1220 if (flags & BPF_F_RDONLY) 1221 return O_RDONLY; 1222 if (flags & BPF_F_WRONLY) 1223 return O_WRONLY; 1224 return O_RDWR; 1225 } 1226 1227 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 1228 #define CHECK_ATTR(CMD) \ 1229 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 1230 sizeof(attr->CMD##_LAST_FIELD), 0, \ 1231 sizeof(*attr) - \ 1232 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 1233 sizeof(attr->CMD##_LAST_FIELD)) != NULL 1234 1235 /* dst and src must have at least "size" number of bytes. 1236 * Return strlen on success and < 0 on error. 1237 */ 1238 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 1239 { 1240 const char *end = src + size; 1241 const char *orig_src = src; 1242 1243 memset(dst, 0, size); 1244 /* Copy all isalnum(), '_' and '.' chars. */ 1245 while (src < end && *src) { 1246 if (!isalnum(*src) && 1247 *src != '_' && *src != '.') 1248 return -EINVAL; 1249 *dst++ = *src++; 1250 } 1251 1252 /* No '\0' found in "size" number of bytes */ 1253 if (src == end) 1254 return -EINVAL; 1255 1256 return src - orig_src; 1257 } 1258 EXPORT_SYMBOL_GPL(bpf_obj_name_cpy); 1259 1260 int map_check_no_btf(struct bpf_map *map, 1261 const struct btf *btf, 1262 const struct btf_type *key_type, 1263 const struct btf_type *value_type) 1264 { 1265 return -ENOTSUPP; 1266 } 1267 1268 static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 1269 const struct btf *btf, u32 btf_key_id, u32 btf_value_id) 1270 { 1271 const struct btf_type *key_type, *value_type; 1272 u32 key_size, value_size; 1273 int ret = 0; 1274 1275 /* Some maps allow key to be unspecified. */ 1276 if (btf_key_id) { 1277 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 1278 if (!key_type || key_size != map->key_size) 1279 return -EINVAL; 1280 } else { 1281 key_type = btf_type_by_id(btf, 0); 1282 if (!map->ops->map_check_btf) 1283 return -EINVAL; 1284 } 1285 1286 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 1287 if (!value_type || value_size != map->value_size) 1288 return -EINVAL; 1289 1290 map->record = btf_parse_fields(btf, value_type, 1291 BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | 1292 BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR | 1293 BPF_TASK_WORK | BPF_RCU_HEAD, 1294 map->value_size); 1295 if (!IS_ERR_OR_NULL(map->record)) { 1296 int i; 1297 1298 if (!bpf_token_capable(token, CAP_BPF)) { 1299 ret = -EPERM; 1300 goto free_map_tab; 1301 } 1302 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { 1303 ret = -EACCES; 1304 goto free_map_tab; 1305 } 1306 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { 1307 switch (map->record->field_mask & (1 << i)) { 1308 case 0: 1309 continue; 1310 case BPF_SPIN_LOCK: 1311 case BPF_RES_SPIN_LOCK: 1312 if (map->map_type != BPF_MAP_TYPE_HASH && 1313 map->map_type != BPF_MAP_TYPE_RHASH && 1314 map->map_type != BPF_MAP_TYPE_ARRAY && 1315 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 1316 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1317 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1318 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1319 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1320 ret = -EOPNOTSUPP; 1321 goto free_map_tab; 1322 } 1323 break; 1324 case BPF_TIMER: 1325 case BPF_WORKQUEUE: 1326 case BPF_TASK_WORK: 1327 if (map->map_type != BPF_MAP_TYPE_HASH && 1328 map->map_type != BPF_MAP_TYPE_RHASH && 1329 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1330 map->map_type != BPF_MAP_TYPE_ARRAY) { 1331 ret = -EOPNOTSUPP; 1332 goto free_map_tab; 1333 } 1334 break; 1335 case BPF_RCU_HEAD: 1336 if (map->map_type != BPF_MAP_TYPE_ARRAY) { 1337 ret = -EOPNOTSUPP; 1338 goto free_map_tab; 1339 } 1340 break; 1341 case BPF_KPTR_UNREF: 1342 case BPF_KPTR_REF: 1343 case BPF_KPTR_PERCPU: 1344 case BPF_REFCOUNT: 1345 if (map->map_type != BPF_MAP_TYPE_HASH && 1346 map->map_type != BPF_MAP_TYPE_RHASH && 1347 map->map_type != BPF_MAP_TYPE_PERCPU_HASH && 1348 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1349 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && 1350 map->map_type != BPF_MAP_TYPE_ARRAY && 1351 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && 1352 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1353 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1354 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1355 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1356 ret = -EOPNOTSUPP; 1357 goto free_map_tab; 1358 } 1359 break; 1360 case BPF_UPTR: 1361 if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) { 1362 ret = -EOPNOTSUPP; 1363 goto free_map_tab; 1364 } 1365 break; 1366 case BPF_LIST_HEAD: 1367 case BPF_RB_ROOT: 1368 if (map->map_type != BPF_MAP_TYPE_HASH && 1369 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1370 map->map_type != BPF_MAP_TYPE_ARRAY) { 1371 ret = -EOPNOTSUPP; 1372 goto free_map_tab; 1373 } 1374 break; 1375 default: 1376 /* Fail if map_type checks are missing for a field type */ 1377 ret = -EOPNOTSUPP; 1378 goto free_map_tab; 1379 } 1380 } 1381 } 1382 1383 ret = btf_check_and_fixup_fields(btf, map->record); 1384 if (ret < 0) 1385 goto free_map_tab; 1386 1387 if (map->ops->map_check_btf) { 1388 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 1389 if (ret < 0) 1390 goto free_map_tab; 1391 } 1392 1393 return ret; 1394 free_map_tab: 1395 bpf_map_free_record(map); 1396 return ret; 1397 } 1398 1399 #define BPF_MAP_CREATE_LAST_FIELD excl_prog_hash_size 1400 /* called via syscall */ 1401 static int map_create_alloc(union bpf_attr *attr, bpfptr_t uattr, struct bpf_verifier_log *log, 1402 struct bpf_map **mapp, struct bpf_token **tokenp) 1403 { 1404 const struct bpf_map_ops *ops; 1405 struct bpf_token *token = NULL; 1406 int numa_node = bpf_map_attr_numa_node(attr); 1407 u32 map_type = attr->map_type; 1408 struct bpf_map *map; 1409 bool token_flag; 1410 int err; 1411 1412 err = CHECK_ATTR(BPF_MAP_CREATE); 1413 if (err) { 1414 bpf_log(log, "Invalid attr.\n"); 1415 return -EINVAL; 1416 } 1417 1418 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it 1419 * to avoid per-map type checks tripping on unknown flag 1420 */ 1421 token_flag = attr->map_flags & BPF_F_TOKEN_FD; 1422 attr->map_flags &= ~BPF_F_TOKEN_FD; 1423 1424 if (attr->btf_vmlinux_value_type_id) { 1425 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS) { 1426 bpf_log(log, "btf_vmlinux_value_type_id can only be used with struct_ops maps.\n"); 1427 return -EINVAL; 1428 } 1429 if (attr->btf_key_type_id || attr->btf_value_type_id) { 1430 bpf_log(log, "btf_vmlinux_value_type_id is mutually exclusive with btf_key_type_id and btf_value_type_id.\n"); 1431 return -EINVAL; 1432 } 1433 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 1434 bpf_log(log, "Invalid btf_value_type_id.\n"); 1435 return -EINVAL; 1436 } 1437 1438 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 1439 attr->map_type != BPF_MAP_TYPE_ARENA && 1440 attr->map_type != BPF_MAP_TYPE_RHASH && 1441 attr->map_extra != 0) { 1442 bpf_log(log, "Invalid map_extra.\n"); 1443 return -EINVAL; 1444 } 1445 1446 if (numa_node != NUMA_NO_NODE && 1447 ((unsigned int)numa_node >= nr_node_ids || 1448 !node_online(numa_node))) { 1449 bpf_log(log, "Invalid numa_node.\n"); 1450 return -EINVAL; 1451 } 1452 1453 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 1454 map_type = attr->map_type; 1455 if (map_type >= ARRAY_SIZE(bpf_map_types)) { 1456 bpf_log(log, "Invalid map_type.\n"); 1457 return -EINVAL; 1458 } 1459 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); 1460 ops = bpf_map_types[map_type]; 1461 if (!ops) 1462 return -EINVAL; 1463 1464 if (ops->map_alloc_check) { 1465 err = ops->map_alloc_check(attr); 1466 if (err) 1467 return err; 1468 } 1469 if (attr->map_ifindex) 1470 ops = &bpf_map_offload_ops; 1471 if (!ops->map_mem_usage) 1472 return -EINVAL; 1473 1474 if (token_flag) { 1475 token = bpf_token_get_from_fd(attr->map_token_fd); 1476 if (IS_ERR(token)) { 1477 bpf_log(log, "Invalid map_token_fd.\n"); 1478 return PTR_ERR(token); 1479 } 1480 1481 /* if current token doesn't grant map creation permissions, 1482 * then we can't use this token, so ignore it and rely on 1483 * system-wide capabilities checks 1484 */ 1485 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || 1486 !bpf_token_allow_map_type(token, attr->map_type)) { 1487 bpf_token_put(token); 1488 token = NULL; 1489 } 1490 } 1491 1492 err = -EPERM; 1493 1494 /* Intent here is for unprivileged_bpf_disabled to block BPF map 1495 * creation for unprivileged users; other actions depend 1496 * on fd availability and access to bpffs, so are dependent on 1497 * object creation success. Even with unprivileged BPF disabled, 1498 * capability checks are still carried out. 1499 */ 1500 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) 1501 goto put_token; 1502 1503 /* check privileged map type permissions */ 1504 switch (map_type) { 1505 case BPF_MAP_TYPE_ARRAY: 1506 case BPF_MAP_TYPE_PERCPU_ARRAY: 1507 case BPF_MAP_TYPE_PROG_ARRAY: 1508 case BPF_MAP_TYPE_PERF_EVENT_ARRAY: 1509 case BPF_MAP_TYPE_CGROUP_ARRAY: 1510 case BPF_MAP_TYPE_ARRAY_OF_MAPS: 1511 case BPF_MAP_TYPE_HASH: 1512 case BPF_MAP_TYPE_RHASH: 1513 case BPF_MAP_TYPE_PERCPU_HASH: 1514 case BPF_MAP_TYPE_HASH_OF_MAPS: 1515 case BPF_MAP_TYPE_RINGBUF: 1516 case BPF_MAP_TYPE_USER_RINGBUF: 1517 case BPF_MAP_TYPE_CGROUP_STORAGE: 1518 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: 1519 /* unprivileged */ 1520 break; 1521 case BPF_MAP_TYPE_SK_STORAGE: 1522 case BPF_MAP_TYPE_INODE_STORAGE: 1523 case BPF_MAP_TYPE_TASK_STORAGE: 1524 case BPF_MAP_TYPE_CGRP_STORAGE: 1525 case BPF_MAP_TYPE_BLOOM_FILTER: 1526 case BPF_MAP_TYPE_LPM_TRIE: 1527 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: 1528 case BPF_MAP_TYPE_STACK_TRACE: 1529 case BPF_MAP_TYPE_QUEUE: 1530 case BPF_MAP_TYPE_STACK: 1531 case BPF_MAP_TYPE_LRU_HASH: 1532 case BPF_MAP_TYPE_LRU_PERCPU_HASH: 1533 case BPF_MAP_TYPE_STRUCT_OPS: 1534 case BPF_MAP_TYPE_CPUMAP: 1535 case BPF_MAP_TYPE_ARENA: 1536 case BPF_MAP_TYPE_INSN_ARRAY: 1537 if (!bpf_token_capable(token, CAP_BPF)) 1538 goto put_token; 1539 break; 1540 case BPF_MAP_TYPE_SOCKMAP: 1541 case BPF_MAP_TYPE_SOCKHASH: 1542 case BPF_MAP_TYPE_DEVMAP: 1543 case BPF_MAP_TYPE_DEVMAP_HASH: 1544 case BPF_MAP_TYPE_XSKMAP: 1545 if (!bpf_token_capable(token, CAP_NET_ADMIN)) 1546 goto put_token; 1547 break; 1548 default: 1549 WARN(1, "unsupported map type %d", map_type); 1550 goto put_token; 1551 } 1552 1553 map = ops->map_alloc(attr); 1554 if (IS_ERR(map)) { 1555 err = PTR_ERR(map); 1556 goto put_token; 1557 } 1558 map->ops = ops; 1559 map->map_type = map_type; 1560 1561 err = bpf_obj_name_cpy(map->name, attr->map_name, 1562 sizeof(attr->map_name)); 1563 if (err < 0) { 1564 bpf_log(log, "Invalid map_name.\n"); 1565 goto free_map; 1566 } 1567 1568 preempt_disable(); 1569 map->cookie = gen_cookie_next(&bpf_map_cookie); 1570 preempt_enable(); 1571 1572 atomic64_set(&map->refcnt, 1); 1573 atomic64_set(&map->usercnt, 1); 1574 mutex_init(&map->freeze_mutex); 1575 spin_lock_init(&map->owner_lock); 1576 1577 if (attr->btf_key_type_id || attr->btf_value_type_id || 1578 /* Even the map's value is a kernel's struct, 1579 * the bpf_prog.o must have BTF to begin with 1580 * to figure out the corresponding kernel's 1581 * counter part. Thus, attr->btf_fd has 1582 * to be valid also. 1583 */ 1584 attr->btf_vmlinux_value_type_id) { 1585 struct btf *btf; 1586 1587 btf = btf_get_by_fd(attr->btf_fd); 1588 if (IS_ERR(btf)) { 1589 bpf_log(log, "Invalid btf_fd.\n"); 1590 err = PTR_ERR(btf); 1591 goto free_map; 1592 } 1593 if (btf_is_kernel(btf)) { 1594 btf_put(btf); 1595 err = -EACCES; 1596 goto free_map; 1597 } 1598 map->btf = btf; 1599 1600 if (attr->btf_value_type_id) { 1601 err = map_check_btf(map, token, btf, attr->btf_key_type_id, 1602 attr->btf_value_type_id); 1603 if (err) 1604 goto free_map; 1605 } 1606 1607 map->btf_key_type_id = attr->btf_key_type_id; 1608 map->btf_value_type_id = attr->btf_value_type_id; 1609 map->btf_vmlinux_value_type_id = 1610 attr->btf_vmlinux_value_type_id; 1611 } 1612 1613 if (attr->excl_prog_hash) { 1614 bpfptr_t uprog_hash = make_bpfptr(attr->excl_prog_hash, uattr.is_kernel); 1615 1616 if (attr->excl_prog_hash_size != SHA256_DIGEST_SIZE) { 1617 bpf_log(log, "Invalid excl_prog_hash_size.\n"); 1618 err = -EINVAL; 1619 goto free_map; 1620 } 1621 1622 map->excl_prog_sha = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); 1623 if (!map->excl_prog_sha) { 1624 err = -ENOMEM; 1625 goto free_map; 1626 } 1627 1628 if (copy_from_bpfptr(map->excl_prog_sha, uprog_hash, SHA256_DIGEST_SIZE)) { 1629 err = -EFAULT; 1630 goto free_map; 1631 } 1632 } else if (attr->excl_prog_hash_size) { 1633 bpf_log(log, "Invalid excl_prog_hash_size.\n"); 1634 err = -EINVAL; 1635 goto free_map; 1636 } 1637 1638 *mapp = map; 1639 *tokenp = token; 1640 return 0; 1641 1642 free_map: 1643 bpf_map_free(map); 1644 put_token: 1645 bpf_token_put(token); 1646 return err; 1647 } 1648 1649 static int map_create(union bpf_attr *attr, bpfptr_t uattr, struct bpf_common_attr *attr_common, 1650 bpfptr_t uattr_common, u32 size_common) 1651 { 1652 struct bpf_token *token = NULL; 1653 struct bpf_verifier_log *log; 1654 struct bpf_log_attr attr_log; 1655 struct bpf_map *map = NULL; 1656 int err, ret; 1657 int f_flags; 1658 1659 log = bpf_log_attr_create_vlog(&attr_log, attr_common, uattr_common, size_common); 1660 if (IS_ERR(log)) 1661 return PTR_ERR(log); 1662 1663 err = map_create_alloc(attr, uattr, log, &map, &token); 1664 1665 /* preserve original error even if log finalization is successful */ 1666 ret = bpf_log_attr_finalize(&attr_log, log); 1667 if (ret) 1668 err = ret; 1669 1670 kfree(log); 1671 1672 if (err) 1673 goto free_map; 1674 1675 f_flags = bpf_get_file_flag(attr->map_flags); 1676 if (f_flags < 0) { 1677 err = f_flags; 1678 goto free_map; 1679 } 1680 1681 err = security_bpf_map_create(map, attr, token, uattr.is_kernel); 1682 if (err) 1683 goto free_map; 1684 1685 err = bpf_map_alloc_id(map); 1686 if (err) 1687 goto free_map_sec; 1688 1689 bpf_map_save_memcg(map); 1690 bpf_token_put(token); 1691 1692 err = bpf_map_new_fd(map, f_flags); 1693 if (err < 0) { 1694 /* failed to allocate fd. 1695 * bpf_map_put_with_uref() is needed because the above 1696 * bpf_map_alloc_id() has published the map 1697 * to the userspace and the userspace may 1698 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 1699 */ 1700 bpf_map_put_with_uref(map); 1701 return err; 1702 } 1703 1704 return err; 1705 1706 free_map_sec: 1707 security_bpf_map_free(map); 1708 free_map: 1709 if (map) 1710 bpf_map_free(map); 1711 bpf_token_put(token); 1712 return err; 1713 } 1714 1715 void bpf_map_inc(struct bpf_map *map) 1716 { 1717 atomic64_inc(&map->refcnt); 1718 } 1719 EXPORT_SYMBOL_GPL(bpf_map_inc); 1720 1721 void bpf_map_inc_with_uref(struct bpf_map *map) 1722 { 1723 atomic64_inc(&map->refcnt); 1724 atomic64_inc(&map->usercnt); 1725 } 1726 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 1727 1728 struct bpf_map *bpf_map_get(u32 ufd) 1729 { 1730 CLASS(fd, f)(ufd); 1731 struct bpf_map *map = __bpf_map_get(f); 1732 1733 if (!IS_ERR(map)) 1734 bpf_map_inc(map); 1735 1736 return map; 1737 } 1738 EXPORT_SYMBOL_NS(bpf_map_get, "BPF_INTERNAL"); 1739 1740 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 1741 { 1742 CLASS(fd, f)(ufd); 1743 struct bpf_map *map = __bpf_map_get(f); 1744 1745 if (!IS_ERR(map)) 1746 bpf_map_inc_with_uref(map); 1747 1748 return map; 1749 } 1750 1751 /* map_idr_lock should have been held or the map should have been 1752 * protected by rcu read lock. 1753 */ 1754 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1755 { 1756 int refold; 1757 1758 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1759 if (!refold) 1760 return ERR_PTR(-ENOENT); 1761 if (uref) 1762 atomic64_inc(&map->usercnt); 1763 1764 return map; 1765 } 1766 1767 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1768 { 1769 lockdep_assert(rcu_read_lock_held()); 1770 return __bpf_map_inc_not_zero(map, false); 1771 } 1772 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1773 1774 int __weak bpf_stackmap_extract(struct bpf_map *map, void *key, void *value, 1775 bool delete) 1776 { 1777 return -ENOTSUPP; 1778 } 1779 1780 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1781 { 1782 if (key_size) 1783 return vmemdup_user(ukey, key_size); 1784 1785 if (ukey) 1786 return ERR_PTR(-EINVAL); 1787 1788 return NULL; 1789 } 1790 1791 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1792 { 1793 if (key_size) 1794 return kvmemdup_bpfptr(ukey, key_size); 1795 1796 if (!bpfptr_is_null(ukey)) 1797 return ERR_PTR(-EINVAL); 1798 1799 return NULL; 1800 } 1801 1802 /* last field in 'union bpf_attr' used by this command */ 1803 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1804 1805 static int map_lookup_elem(union bpf_attr *attr) 1806 { 1807 void __user *ukey = u64_to_user_ptr(attr->key); 1808 void __user *uvalue = u64_to_user_ptr(attr->value); 1809 struct bpf_map *map; 1810 void *key, *value; 1811 u32 value_size; 1812 int err; 1813 1814 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1815 return -EINVAL; 1816 1817 CLASS(fd, f)(attr->map_fd); 1818 map = __bpf_map_get(f); 1819 if (IS_ERR(map)) 1820 return PTR_ERR(map); 1821 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1822 return -EPERM; 1823 1824 err = bpf_map_check_op_flags(map, attr->flags, BPF_F_LOCK | BPF_F_CPU); 1825 if (err) 1826 return err; 1827 1828 key = __bpf_copy_key(ukey, map->key_size); 1829 if (IS_ERR(key)) 1830 return PTR_ERR(key); 1831 1832 value_size = bpf_map_value_size(map, attr->flags); 1833 1834 err = -ENOMEM; 1835 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1836 if (!value) 1837 goto free_key; 1838 1839 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1840 if (copy_from_user(value, uvalue, value_size)) 1841 err = -EFAULT; 1842 else 1843 err = bpf_map_copy_value(map, key, value, attr->flags); 1844 goto free_value; 1845 } 1846 1847 err = bpf_map_copy_value(map, key, value, attr->flags); 1848 if (err) 1849 goto free_value; 1850 1851 err = -EFAULT; 1852 if (copy_to_user(uvalue, value, value_size) != 0) 1853 goto free_value; 1854 1855 err = 0; 1856 1857 free_value: 1858 kvfree(value); 1859 free_key: 1860 kvfree(key); 1861 return err; 1862 } 1863 1864 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1865 1866 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1867 { 1868 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1869 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1870 struct bpf_map *map; 1871 void *key, *value; 1872 u32 value_size; 1873 int err; 1874 1875 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1876 return -EINVAL; 1877 1878 CLASS(fd, f)(attr->map_fd); 1879 map = __bpf_map_get(f); 1880 if (IS_ERR(map)) 1881 return PTR_ERR(map); 1882 bpf_map_write_active_inc(map); 1883 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1884 err = -EPERM; 1885 goto err_put; 1886 } 1887 1888 err = bpf_map_check_op_flags(map, attr->flags, ~0); 1889 if (err) 1890 goto err_put; 1891 1892 key = ___bpf_copy_key(ukey, map->key_size); 1893 if (IS_ERR(key)) { 1894 err = PTR_ERR(key); 1895 goto err_put; 1896 } 1897 1898 value_size = bpf_map_value_size(map, attr->flags); 1899 value = kvmemdup_bpfptr(uvalue, value_size); 1900 if (IS_ERR(value)) { 1901 err = PTR_ERR(value); 1902 goto free_key; 1903 } 1904 1905 err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags); 1906 if (!err) 1907 maybe_wait_bpf_programs(map); 1908 1909 kvfree(value); 1910 free_key: 1911 kvfree(key); 1912 err_put: 1913 bpf_map_write_active_dec(map); 1914 return err; 1915 } 1916 1917 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1918 1919 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) 1920 { 1921 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1922 struct bpf_map *map; 1923 void *key; 1924 int err; 1925 1926 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1927 return -EINVAL; 1928 1929 CLASS(fd, f)(attr->map_fd); 1930 map = __bpf_map_get(f); 1931 if (IS_ERR(map)) 1932 return PTR_ERR(map); 1933 bpf_map_write_active_inc(map); 1934 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1935 err = -EPERM; 1936 goto err_put; 1937 } 1938 1939 key = ___bpf_copy_key(ukey, map->key_size); 1940 if (IS_ERR(key)) { 1941 err = PTR_ERR(key); 1942 goto err_put; 1943 } 1944 1945 if (bpf_map_is_offloaded(map)) { 1946 err = bpf_map_offload_delete_elem(map, key); 1947 goto out; 1948 } else if (IS_FD_PROG_ARRAY(map) || 1949 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1950 /* These maps require sleepable context */ 1951 err = map->ops->map_delete_elem(map, key); 1952 goto out; 1953 } 1954 1955 bpf_disable_instrumentation(); 1956 rcu_read_lock(); 1957 err = map->ops->map_delete_elem(map, key); 1958 rcu_read_unlock(); 1959 bpf_enable_instrumentation(); 1960 if (!err) 1961 maybe_wait_bpf_programs(map); 1962 out: 1963 kvfree(key); 1964 err_put: 1965 bpf_map_write_active_dec(map); 1966 return err; 1967 } 1968 1969 /* last field in 'union bpf_attr' used by this command */ 1970 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1971 1972 static int map_get_next_key(union bpf_attr *attr) 1973 { 1974 void __user *ukey = u64_to_user_ptr(attr->key); 1975 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1976 struct bpf_map *map; 1977 void *key, *next_key; 1978 int err; 1979 1980 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1981 return -EINVAL; 1982 1983 CLASS(fd, f)(attr->map_fd); 1984 map = __bpf_map_get(f); 1985 if (IS_ERR(map)) 1986 return PTR_ERR(map); 1987 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1988 return -EPERM; 1989 1990 if (ukey) { 1991 key = __bpf_copy_key(ukey, map->key_size); 1992 if (IS_ERR(key)) 1993 return PTR_ERR(key); 1994 } else { 1995 key = NULL; 1996 } 1997 1998 err = -ENOMEM; 1999 next_key = kvmalloc(map->key_size, GFP_USER); 2000 if (!next_key) 2001 goto free_key; 2002 2003 if (bpf_map_is_offloaded(map)) { 2004 err = bpf_map_offload_get_next_key(map, key, next_key); 2005 goto out; 2006 } 2007 2008 rcu_read_lock(); 2009 err = map->ops->map_get_next_key(map, key, next_key); 2010 rcu_read_unlock(); 2011 out: 2012 if (err) 2013 goto free_next_key; 2014 2015 err = -EFAULT; 2016 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 2017 goto free_next_key; 2018 2019 err = 0; 2020 2021 free_next_key: 2022 kvfree(next_key); 2023 free_key: 2024 kvfree(key); 2025 return err; 2026 } 2027 2028 int generic_map_delete_batch(struct bpf_map *map, 2029 const union bpf_attr *attr, 2030 union bpf_attr __user *uattr) 2031 { 2032 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2033 u32 cp, max_count; 2034 int err = 0; 2035 void *key; 2036 2037 if (attr->batch.elem_flags & ~BPF_F_LOCK) 2038 return -EINVAL; 2039 2040 if ((attr->batch.elem_flags & BPF_F_LOCK) && 2041 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2042 return -EINVAL; 2043 } 2044 2045 max_count = attr->batch.count; 2046 if (!max_count) 2047 return 0; 2048 2049 if (put_user(0, &uattr->batch.count)) 2050 return -EFAULT; 2051 2052 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2053 if (!key) 2054 return -ENOMEM; 2055 2056 for (cp = 0; cp < max_count; cp++) { 2057 err = -EFAULT; 2058 if (copy_from_user(key, keys + (size_t)cp * map->key_size, 2059 map->key_size)) 2060 break; 2061 2062 if (bpf_map_is_offloaded(map)) { 2063 err = bpf_map_offload_delete_elem(map, key); 2064 break; 2065 } 2066 2067 bpf_disable_instrumentation(); 2068 rcu_read_lock(); 2069 err = map->ops->map_delete_elem(map, key); 2070 rcu_read_unlock(); 2071 bpf_enable_instrumentation(); 2072 if (err) 2073 break; 2074 cond_resched(); 2075 } 2076 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 2077 err = -EFAULT; 2078 2079 kvfree(key); 2080 2081 return err; 2082 } 2083 2084 int generic_map_update_batch(struct bpf_map *map, struct file *map_file, 2085 const union bpf_attr *attr, 2086 union bpf_attr __user *uattr) 2087 { 2088 void __user *values = u64_to_user_ptr(attr->batch.values); 2089 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2090 u32 value_size, cp, max_count; 2091 void *key, *value; 2092 int err = 0; 2093 2094 err = bpf_map_check_op_flags(map, attr->batch.elem_flags, 2095 BPF_F_LOCK | BPF_F_CPU | BPF_F_ALL_CPUS); 2096 if (err) 2097 return err; 2098 2099 value_size = bpf_map_value_size(map, attr->batch.elem_flags); 2100 2101 max_count = attr->batch.count; 2102 if (!max_count) 2103 return 0; 2104 2105 if (put_user(0, &uattr->batch.count)) 2106 return -EFAULT; 2107 2108 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2109 if (!key) 2110 return -ENOMEM; 2111 2112 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2113 if (!value) { 2114 kvfree(key); 2115 return -ENOMEM; 2116 } 2117 2118 for (cp = 0; cp < max_count; cp++) { 2119 err = -EFAULT; 2120 if (copy_from_user(key, keys + (size_t)cp * map->key_size, 2121 map->key_size) || 2122 copy_from_user(value, values + (size_t)cp * value_size, value_size)) 2123 break; 2124 2125 err = bpf_map_update_value(map, map_file, key, value, 2126 attr->batch.elem_flags); 2127 2128 if (err) 2129 break; 2130 cond_resched(); 2131 } 2132 2133 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 2134 err = -EFAULT; 2135 2136 kvfree(value); 2137 kvfree(key); 2138 2139 return err; 2140 } 2141 2142 int generic_map_lookup_batch(struct bpf_map *map, 2143 const union bpf_attr *attr, 2144 union bpf_attr __user *uattr) 2145 { 2146 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 2147 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 2148 void __user *values = u64_to_user_ptr(attr->batch.values); 2149 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2150 void *buf, *buf_prevkey, *prev_key, *key, *value; 2151 u32 value_size, cp, max_count; 2152 int err; 2153 2154 err = bpf_map_check_op_flags(map, attr->batch.elem_flags, BPF_F_LOCK | BPF_F_CPU); 2155 if (err) 2156 return err; 2157 2158 value_size = bpf_map_value_size(map, attr->batch.elem_flags); 2159 2160 max_count = attr->batch.count; 2161 if (!max_count) 2162 return 0; 2163 2164 if (put_user(0, &uattr->batch.count)) 2165 return -EFAULT; 2166 2167 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2168 if (!buf_prevkey) 2169 return -ENOMEM; 2170 2171 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 2172 if (!buf) { 2173 kvfree(buf_prevkey); 2174 return -ENOMEM; 2175 } 2176 2177 err = -EFAULT; 2178 prev_key = NULL; 2179 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 2180 goto free_buf; 2181 key = buf; 2182 value = key + map->key_size; 2183 if (ubatch) 2184 prev_key = buf_prevkey; 2185 2186 for (cp = 0; cp < max_count;) { 2187 rcu_read_lock(); 2188 err = map->ops->map_get_next_key(map, prev_key, key); 2189 rcu_read_unlock(); 2190 if (err) 2191 break; 2192 err = bpf_map_copy_value(map, key, value, 2193 attr->batch.elem_flags); 2194 2195 if (err == -ENOENT) 2196 goto next_key; 2197 2198 if (err) 2199 goto free_buf; 2200 2201 if (copy_to_user(keys + (size_t)cp * map->key_size, key, 2202 map->key_size)) { 2203 err = -EFAULT; 2204 goto free_buf; 2205 } 2206 if (copy_to_user(values + (size_t)cp * value_size, value, value_size)) { 2207 err = -EFAULT; 2208 goto free_buf; 2209 } 2210 2211 cp++; 2212 next_key: 2213 if (!prev_key) 2214 prev_key = buf_prevkey; 2215 2216 swap(prev_key, key); 2217 cond_resched(); 2218 } 2219 2220 if (err == -EFAULT) 2221 goto free_buf; 2222 2223 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 2224 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 2225 err = -EFAULT; 2226 2227 free_buf: 2228 kvfree(buf_prevkey); 2229 kvfree(buf); 2230 return err; 2231 } 2232 2233 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 2234 2235 static int map_lookup_and_delete_elem(union bpf_attr *attr) 2236 { 2237 void __user *ukey = u64_to_user_ptr(attr->key); 2238 void __user *uvalue = u64_to_user_ptr(attr->value); 2239 struct bpf_map *map; 2240 void *key, *value; 2241 u32 value_size; 2242 int err; 2243 2244 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 2245 return -EINVAL; 2246 2247 if (attr->flags & ~BPF_F_LOCK) 2248 return -EINVAL; 2249 2250 CLASS(fd, f)(attr->map_fd); 2251 map = __bpf_map_get(f); 2252 if (IS_ERR(map)) 2253 return PTR_ERR(map); 2254 bpf_map_write_active_inc(map); 2255 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 2256 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 2257 err = -EPERM; 2258 goto err_put; 2259 } 2260 2261 if (attr->flags && 2262 (map->map_type == BPF_MAP_TYPE_QUEUE || 2263 map->map_type == BPF_MAP_TYPE_STACK)) { 2264 err = -EINVAL; 2265 goto err_put; 2266 } 2267 2268 if ((attr->flags & BPF_F_LOCK) && 2269 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2270 err = -EINVAL; 2271 goto err_put; 2272 } 2273 2274 key = __bpf_copy_key(ukey, map->key_size); 2275 if (IS_ERR(key)) { 2276 err = PTR_ERR(key); 2277 goto err_put; 2278 } 2279 2280 value_size = bpf_map_value_size(map, 0); 2281 2282 err = -ENOMEM; 2283 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2284 if (!value) 2285 goto free_key; 2286 2287 err = -ENOTSUPP; 2288 if (map->map_type == BPF_MAP_TYPE_QUEUE || 2289 map->map_type == BPF_MAP_TYPE_STACK) { 2290 err = map->ops->map_pop_elem(map, value); 2291 } else if (map->map_type == BPF_MAP_TYPE_HASH || 2292 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 2293 map->map_type == BPF_MAP_TYPE_LRU_HASH || 2294 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 2295 map->map_type == BPF_MAP_TYPE_RHASH || 2296 map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 2297 if (!bpf_map_is_offloaded(map)) { 2298 bpf_disable_instrumentation(); 2299 rcu_read_lock(); 2300 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 2301 rcu_read_unlock(); 2302 bpf_enable_instrumentation(); 2303 } 2304 } 2305 2306 if (err) 2307 goto free_value; 2308 2309 if (copy_to_user(uvalue, value, value_size) != 0) { 2310 err = -EFAULT; 2311 goto free_value; 2312 } 2313 2314 err = 0; 2315 2316 free_value: 2317 kvfree(value); 2318 free_key: 2319 kvfree(key); 2320 err_put: 2321 bpf_map_write_active_dec(map); 2322 return err; 2323 } 2324 2325 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 2326 2327 static int map_freeze(const union bpf_attr *attr) 2328 { 2329 int err = 0; 2330 struct bpf_map *map; 2331 2332 if (CHECK_ATTR(BPF_MAP_FREEZE)) 2333 return -EINVAL; 2334 2335 CLASS(fd, f)(attr->map_fd); 2336 map = __bpf_map_get(f); 2337 if (IS_ERR(map)) 2338 return PTR_ERR(map); 2339 2340 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) 2341 return -ENOTSUPP; 2342 2343 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) 2344 return -EPERM; 2345 2346 mutex_lock(&map->freeze_mutex); 2347 if (bpf_map_write_active(map)) { 2348 err = -EBUSY; 2349 goto err_put; 2350 } 2351 if (READ_ONCE(map->frozen)) { 2352 err = -EBUSY; 2353 goto err_put; 2354 } 2355 2356 WRITE_ONCE(map->frozen, true); 2357 err_put: 2358 mutex_unlock(&map->freeze_mutex); 2359 return err; 2360 } 2361 2362 static const struct bpf_prog_ops * const bpf_prog_types[] = { 2363 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 2364 [_id] = & _name ## _prog_ops, 2365 #define BPF_MAP_TYPE(_id, _ops) 2366 #define BPF_LINK_TYPE(_id, _name) 2367 #include <linux/bpf_types.h> 2368 #undef BPF_PROG_TYPE 2369 #undef BPF_MAP_TYPE 2370 #undef BPF_LINK_TYPE 2371 }; 2372 2373 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 2374 { 2375 const struct bpf_prog_ops *ops; 2376 2377 if (type >= ARRAY_SIZE(bpf_prog_types)) 2378 return -EINVAL; 2379 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 2380 ops = bpf_prog_types[type]; 2381 if (!ops) 2382 return -EINVAL; 2383 2384 if (!bpf_prog_is_offloaded(prog->aux)) 2385 prog->aux->ops = ops; 2386 else 2387 prog->aux->ops = &bpf_offload_prog_ops; 2388 prog->type = type; 2389 return 0; 2390 } 2391 2392 enum bpf_audit { 2393 BPF_AUDIT_LOAD, 2394 BPF_AUDIT_UNLOAD, 2395 BPF_AUDIT_MAX, 2396 }; 2397 2398 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 2399 [BPF_AUDIT_LOAD] = "LOAD", 2400 [BPF_AUDIT_UNLOAD] = "UNLOAD", 2401 }; 2402 2403 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 2404 { 2405 struct audit_context *ctx = NULL; 2406 struct audit_buffer *ab; 2407 2408 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 2409 return; 2410 if (audit_enabled == AUDIT_OFF) 2411 return; 2412 if (!in_hardirq() && !irqs_disabled()) 2413 ctx = audit_context(); 2414 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 2415 if (unlikely(!ab)) 2416 return; 2417 audit_log_format(ab, "prog-id=%u op=%s", 2418 prog->aux->id, bpf_audit_str[op]); 2419 audit_log_end(ab); 2420 } 2421 2422 static int bpf_prog_alloc_id(struct bpf_prog *prog) 2423 { 2424 int id; 2425 2426 idr_preload(GFP_KERNEL); 2427 spin_lock_bh(&prog_idr_lock); 2428 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 2429 if (id > 0) 2430 prog->aux->id = id; 2431 spin_unlock_bh(&prog_idr_lock); 2432 idr_preload_end(); 2433 2434 /* id is in [1, INT_MAX) */ 2435 if (WARN_ON_ONCE(!id)) 2436 return -ENOSPC; 2437 2438 return id > 0 ? 0 : id; 2439 } 2440 2441 void bpf_prog_free_id(struct bpf_prog *prog) 2442 { 2443 unsigned long flags; 2444 2445 /* cBPF to eBPF migrations are currently not in the idr store. 2446 * Offloaded programs are removed from the store when their device 2447 * disappears - even if someone grabs an fd to them they are unusable, 2448 * simply waiting for refcnt to drop to be freed. 2449 */ 2450 if (!prog->aux->id) 2451 return; 2452 2453 spin_lock_irqsave(&prog_idr_lock, flags); 2454 idr_remove(&prog_idr, prog->aux->id); 2455 prog->aux->id = 0; 2456 spin_unlock_irqrestore(&prog_idr_lock, flags); 2457 } 2458 2459 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 2460 { 2461 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 2462 2463 btf_put(aux->btf); 2464 kvfree(aux->jited_linfo); 2465 kvfree(aux->linfo); 2466 kvfree(aux->func_info); 2467 kfree(aux->func_info_aux); 2468 free_uid(aux->user); 2469 security_bpf_prog_free(aux->prog); 2470 bpf_prog_free(aux->prog); 2471 } 2472 2473 /* 2474 * Progs called from a trampoline can also be reached by a task that was 2475 * preempted in the trampoline before the prog's enter helper took its RCU 2476 * read lock, wait for those first. 2477 */ 2478 static void __bpf_prog_put_rcu_tasks(struct rcu_head *rcu) 2479 { 2480 struct bpf_prog *prog = container_of(rcu, struct bpf_prog_aux, rcu)->prog; 2481 2482 if (bpf_prog_runs_sleepable(prog)) 2483 call_rcu_tasks_trace(rcu, __bpf_prog_put_rcu); 2484 else 2485 call_rcu(rcu, __bpf_prog_put_rcu); 2486 } 2487 2488 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 2489 { 2490 module_put(prog->aux->mod); 2491 kfree(prog->aux->kfunc_tab); 2492 kfree(prog->aux->ctx_arg_info); 2493 if (prog->aux->attach_btf) 2494 btf_put(prog->aux->attach_btf); 2495 2496 if (deferred) { 2497 if (IS_ENABLED(CONFIG_TASKS_RCU) && prog->aux->tramp_linked) 2498 call_rcu_tasks(&prog->aux->rcu, __bpf_prog_put_rcu_tasks); 2499 else if (bpf_prog_runs_sleepable(prog)) 2500 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 2501 else 2502 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 2503 } else { 2504 __bpf_prog_put_rcu(&prog->aux->rcu); 2505 } 2506 } 2507 2508 static void bpf_prog_put_deferred(struct work_struct *work) 2509 { 2510 struct bpf_prog_aux *aux; 2511 struct bpf_prog *prog; 2512 2513 aux = container_of(work, struct bpf_prog_aux, work); 2514 prog = aux->prog; 2515 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 2516 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 2517 bpf_prog_free_id(prog); 2518 __bpf_prog_put_noref(prog, true); 2519 } 2520 2521 static void __bpf_prog_put(struct bpf_prog *prog) 2522 { 2523 struct bpf_prog_aux *aux = prog->aux; 2524 2525 if (atomic64_dec_and_test(&aux->refcnt)) { 2526 if (in_hardirq() || irqs_disabled()) { 2527 INIT_WORK(&aux->work, bpf_prog_put_deferred); 2528 schedule_work(&aux->work); 2529 } else { 2530 bpf_prog_put_deferred(&aux->work); 2531 } 2532 } 2533 } 2534 2535 void bpf_prog_put(struct bpf_prog *prog) 2536 { 2537 __bpf_prog_put(prog); 2538 } 2539 EXPORT_SYMBOL_GPL(bpf_prog_put); 2540 2541 static int bpf_prog_release(struct inode *inode, struct file *filp) 2542 { 2543 struct bpf_prog *prog = filp->private_data; 2544 2545 bpf_prog_put(prog); 2546 return 0; 2547 } 2548 2549 struct bpf_prog_kstats { 2550 u64 nsecs; 2551 u64 cnt; 2552 u64 misses; 2553 }; 2554 2555 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) 2556 { 2557 struct bpf_prog_stats *stats; 2558 unsigned int flags; 2559 2560 if (unlikely(!prog->stats)) 2561 return; 2562 2563 stats = this_cpu_ptr(prog->stats); 2564 flags = u64_stats_update_begin_irqsave(&stats->syncp); 2565 u64_stats_inc(&stats->misses); 2566 u64_stats_update_end_irqrestore(&stats->syncp, flags); 2567 } 2568 2569 static void bpf_prog_get_stats(const struct bpf_prog *prog, 2570 struct bpf_prog_kstats *stats) 2571 { 2572 u64 nsecs = 0, cnt = 0, misses = 0; 2573 int cpu; 2574 2575 for_each_possible_cpu(cpu) { 2576 const struct bpf_prog_stats *st; 2577 unsigned int start; 2578 u64 tnsecs, tcnt, tmisses; 2579 2580 st = per_cpu_ptr(prog->stats, cpu); 2581 do { 2582 start = u64_stats_fetch_begin(&st->syncp); 2583 tnsecs = u64_stats_read(&st->nsecs); 2584 tcnt = u64_stats_read(&st->cnt); 2585 tmisses = u64_stats_read(&st->misses); 2586 } while (u64_stats_fetch_retry(&st->syncp, start)); 2587 nsecs += tnsecs; 2588 cnt += tcnt; 2589 misses += tmisses; 2590 } 2591 stats->nsecs = nsecs; 2592 stats->cnt = cnt; 2593 stats->misses = misses; 2594 } 2595 2596 #ifdef CONFIG_PROC_FS 2597 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 2598 { 2599 const struct bpf_prog *prog = filp->private_data; 2600 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2601 struct bpf_prog_kstats stats; 2602 2603 bpf_prog_get_stats(prog, &stats); 2604 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2605 seq_printf(m, 2606 "prog_type:\t%u\n" 2607 "prog_jited:\t%u\n" 2608 "prog_tag:\t%s\n" 2609 "memlock:\t%llu\n" 2610 "prog_id:\t%u\n" 2611 "run_time_ns:\t%llu\n" 2612 "run_cnt:\t%llu\n" 2613 "recursion_misses:\t%llu\n" 2614 "verified_insns:\t%u\n", 2615 prog->type, 2616 prog->jited, 2617 prog_tag, 2618 prog->pages * 1ULL << PAGE_SHIFT, 2619 prog->aux->id, 2620 stats.nsecs, 2621 stats.cnt, 2622 stats.misses, 2623 prog->aux->verified_insns); 2624 } 2625 #endif 2626 2627 const struct file_operations bpf_prog_fops = { 2628 #ifdef CONFIG_PROC_FS 2629 .show_fdinfo = bpf_prog_show_fdinfo, 2630 #endif 2631 .release = bpf_prog_release, 2632 .read = bpf_dummy_read, 2633 .write = bpf_dummy_write, 2634 }; 2635 2636 int bpf_prog_new_fd(struct bpf_prog *prog) 2637 { 2638 int ret; 2639 2640 ret = security_bpf_prog(prog); 2641 if (ret < 0) 2642 return ret; 2643 2644 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 2645 O_RDWR | O_CLOEXEC); 2646 } 2647 2648 void bpf_prog_add(struct bpf_prog *prog, int i) 2649 { 2650 atomic64_add(i, &prog->aux->refcnt); 2651 } 2652 EXPORT_SYMBOL_GPL(bpf_prog_add); 2653 2654 void bpf_prog_sub(struct bpf_prog *prog, int i) 2655 { 2656 /* Only to be used for undoing previous bpf_prog_add() in some 2657 * error path. We still know that another entity in our call 2658 * path holds a reference to the program, thus atomic_sub() can 2659 * be safely used in such cases! 2660 */ 2661 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 2662 } 2663 EXPORT_SYMBOL_GPL(bpf_prog_sub); 2664 2665 void bpf_prog_inc(struct bpf_prog *prog) 2666 { 2667 atomic64_inc(&prog->aux->refcnt); 2668 } 2669 EXPORT_SYMBOL_GPL(bpf_prog_inc); 2670 2671 /* prog_idr_lock should have been held */ 2672 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 2673 { 2674 int refold; 2675 2676 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 2677 2678 if (!refold) 2679 return ERR_PTR(-ENOENT); 2680 2681 return prog; 2682 } 2683 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 2684 2685 bool bpf_prog_get_ok(struct bpf_prog *prog, 2686 enum bpf_prog_type *attach_type, bool attach_drv) 2687 { 2688 /* not an attachment, just a refcount inc, always allow */ 2689 if (!attach_type) 2690 return true; 2691 2692 if (prog->type != *attach_type) 2693 return false; 2694 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) 2695 return false; 2696 2697 return true; 2698 } 2699 2700 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 2701 bool attach_drv) 2702 { 2703 CLASS(fd, f)(ufd); 2704 struct bpf_prog *prog; 2705 2706 if (fd_empty(f)) 2707 return ERR_PTR(-EBADF); 2708 if (fd_file(f)->f_op != &bpf_prog_fops) 2709 return ERR_PTR(-EINVAL); 2710 2711 prog = fd_file(f)->private_data; 2712 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) 2713 return ERR_PTR(-EINVAL); 2714 2715 bpf_prog_inc(prog); 2716 return prog; 2717 } 2718 2719 struct bpf_prog *bpf_prog_get(u32 ufd) 2720 { 2721 return __bpf_prog_get(ufd, NULL, false); 2722 } 2723 2724 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2725 bool attach_drv) 2726 { 2727 return __bpf_prog_get(ufd, &type, attach_drv); 2728 } 2729 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2730 2731 /* Initially all BPF programs could be loaded w/o specifying 2732 * expected_attach_type. Later for some of them specifying expected_attach_type 2733 * at load time became required so that program could be validated properly. 2734 * Programs of types that are allowed to be loaded both w/ and w/o (for 2735 * backward compatibility) expected_attach_type, should have the default attach 2736 * type assigned to expected_attach_type for the latter case, so that it can be 2737 * validated later at attach time. 2738 * 2739 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2740 * prog type requires it but has some attach types that have to be backward 2741 * compatible. 2742 */ 2743 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2744 { 2745 switch (attr->prog_type) { 2746 case BPF_PROG_TYPE_CGROUP_SOCK: 2747 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2748 * exist so checking for non-zero is the way to go here. 2749 */ 2750 if (!attr->expected_attach_type) 2751 attr->expected_attach_type = 2752 BPF_CGROUP_INET_SOCK_CREATE; 2753 break; 2754 case BPF_PROG_TYPE_SK_REUSEPORT: 2755 if (!attr->expected_attach_type) 2756 attr->expected_attach_type = 2757 BPF_SK_REUSEPORT_SELECT; 2758 break; 2759 } 2760 } 2761 2762 static int 2763 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2764 enum bpf_attach_type expected_attach_type, 2765 struct btf *attach_btf, u32 btf_id, 2766 struct bpf_prog *dst_prog, 2767 bool multi_func) 2768 { 2769 if (btf_id) { 2770 if (btf_id > BTF_MAX_TYPE) 2771 return -EINVAL; 2772 2773 if (!attach_btf && !dst_prog) 2774 return -EINVAL; 2775 2776 switch (prog_type) { 2777 case BPF_PROG_TYPE_TRACING: 2778 case BPF_PROG_TYPE_LSM: 2779 case BPF_PROG_TYPE_STRUCT_OPS: 2780 case BPF_PROG_TYPE_EXT: 2781 break; 2782 default: 2783 return -EINVAL; 2784 } 2785 } 2786 2787 if (multi_func) { 2788 if (prog_type != BPF_PROG_TYPE_TRACING) 2789 return -EINVAL; 2790 if (!attach_btf || btf_id) 2791 return -EINVAL; 2792 return 0; 2793 } 2794 2795 if (attach_btf && (!btf_id || dst_prog)) 2796 return -EINVAL; 2797 2798 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2799 prog_type != BPF_PROG_TYPE_EXT) 2800 return -EINVAL; 2801 2802 switch (prog_type) { 2803 case BPF_PROG_TYPE_CGROUP_SOCK: 2804 switch (expected_attach_type) { 2805 case BPF_CGROUP_INET_SOCK_CREATE: 2806 case BPF_CGROUP_INET_SOCK_RELEASE: 2807 case BPF_CGROUP_INET4_POST_BIND: 2808 case BPF_CGROUP_INET6_POST_BIND: 2809 return 0; 2810 default: 2811 return -EINVAL; 2812 } 2813 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2814 switch (expected_attach_type) { 2815 case BPF_CGROUP_INET4_BIND: 2816 case BPF_CGROUP_INET6_BIND: 2817 case BPF_CGROUP_INET4_CONNECT: 2818 case BPF_CGROUP_INET6_CONNECT: 2819 case BPF_CGROUP_UNIX_CONNECT: 2820 case BPF_CGROUP_INET4_GETPEERNAME: 2821 case BPF_CGROUP_INET6_GETPEERNAME: 2822 case BPF_CGROUP_UNIX_GETPEERNAME: 2823 case BPF_CGROUP_INET4_GETSOCKNAME: 2824 case BPF_CGROUP_INET6_GETSOCKNAME: 2825 case BPF_CGROUP_UNIX_GETSOCKNAME: 2826 case BPF_CGROUP_UDP4_SENDMSG: 2827 case BPF_CGROUP_UDP6_SENDMSG: 2828 case BPF_CGROUP_UNIX_SENDMSG: 2829 case BPF_CGROUP_UDP4_RECVMSG: 2830 case BPF_CGROUP_UDP6_RECVMSG: 2831 case BPF_CGROUP_UNIX_RECVMSG: 2832 return 0; 2833 default: 2834 return -EINVAL; 2835 } 2836 case BPF_PROG_TYPE_CGROUP_SKB: 2837 switch (expected_attach_type) { 2838 case BPF_CGROUP_INET_INGRESS: 2839 case BPF_CGROUP_INET_EGRESS: 2840 return 0; 2841 default: 2842 return -EINVAL; 2843 } 2844 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2845 switch (expected_attach_type) { 2846 case BPF_CGROUP_SETSOCKOPT: 2847 case BPF_CGROUP_GETSOCKOPT: 2848 return 0; 2849 default: 2850 return -EINVAL; 2851 } 2852 case BPF_PROG_TYPE_SK_LOOKUP: 2853 if (expected_attach_type == BPF_SK_LOOKUP) 2854 return 0; 2855 return -EINVAL; 2856 case BPF_PROG_TYPE_SK_REUSEPORT: 2857 switch (expected_attach_type) { 2858 case BPF_SK_REUSEPORT_SELECT: 2859 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2860 return 0; 2861 default: 2862 return -EINVAL; 2863 } 2864 case BPF_PROG_TYPE_NETFILTER: 2865 if (expected_attach_type == BPF_NETFILTER) 2866 return 0; 2867 return -EINVAL; 2868 case BPF_PROG_TYPE_SYSCALL: 2869 case BPF_PROG_TYPE_EXT: 2870 if (expected_attach_type) 2871 return -EINVAL; 2872 fallthrough; 2873 default: 2874 return 0; 2875 } 2876 } 2877 2878 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2879 { 2880 switch (prog_type) { 2881 case BPF_PROG_TYPE_SCHED_CLS: 2882 case BPF_PROG_TYPE_SCHED_ACT: 2883 case BPF_PROG_TYPE_XDP: 2884 case BPF_PROG_TYPE_LWT_IN: 2885 case BPF_PROG_TYPE_LWT_OUT: 2886 case BPF_PROG_TYPE_LWT_XMIT: 2887 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2888 case BPF_PROG_TYPE_SK_SKB: 2889 case BPF_PROG_TYPE_SK_MSG: 2890 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2891 case BPF_PROG_TYPE_CGROUP_DEVICE: 2892 case BPF_PROG_TYPE_CGROUP_SOCK: 2893 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2894 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2895 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2896 case BPF_PROG_TYPE_SOCK_OPS: 2897 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2898 case BPF_PROG_TYPE_NETFILTER: 2899 return true; 2900 case BPF_PROG_TYPE_CGROUP_SKB: 2901 /* always unpriv */ 2902 case BPF_PROG_TYPE_SK_REUSEPORT: 2903 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2904 default: 2905 return false; 2906 } 2907 } 2908 2909 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2910 { 2911 switch (prog_type) { 2912 case BPF_PROG_TYPE_KPROBE: 2913 case BPF_PROG_TYPE_TRACEPOINT: 2914 case BPF_PROG_TYPE_PERF_EVENT: 2915 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2916 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2917 case BPF_PROG_TYPE_TRACING: 2918 case BPF_PROG_TYPE_LSM: 2919 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2920 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2921 return true; 2922 default: 2923 return false; 2924 } 2925 } 2926 2927 static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog) 2928 { 2929 int err; 2930 int i; 2931 2932 for (i = 0; i < prog->aux->used_map_cnt; i++) { 2933 if (prog->aux->used_maps[i]->map_type != BPF_MAP_TYPE_INSN_ARRAY) 2934 continue; 2935 2936 err = bpf_insn_array_ready(prog->aux->used_maps[i]); 2937 if (err) 2938 return err; 2939 } 2940 2941 return 0; 2942 } 2943 2944 extern int bpf_multi_func(void); 2945 int __init __used bpf_multi_func(void) { return 0; } 2946 2947 BTF_ID_LIST_GLOBAL_SINGLE(bpf_multi_func_btf_id, func, bpf_multi_func) 2948 2949 /* last field in 'union bpf_attr' used by this command */ 2950 #define BPF_PROG_LOAD_LAST_FIELD keyring_id 2951 2952 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_attr *attr_log) 2953 { 2954 enum bpf_prog_type type = attr->prog_type; 2955 struct bpf_prog *prog, *dst_prog = NULL; 2956 struct btf *attach_btf = NULL; 2957 struct bpf_token *token = NULL; 2958 bool bpf_cap; 2959 int err; 2960 char license[128]; 2961 bool multi_func; 2962 2963 if (CHECK_ATTR(BPF_PROG_LOAD)) 2964 return -EINVAL; 2965 2966 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2967 BPF_F_ANY_ALIGNMENT | 2968 BPF_F_TEST_STATE_FREQ | 2969 BPF_F_SLEEPABLE | 2970 BPF_F_TEST_RND_HI32 | 2971 BPF_F_XDP_HAS_FRAGS | 2972 BPF_F_XDP_DEV_BOUND_ONLY | 2973 BPF_F_TEST_REG_INVARIANTS | 2974 BPF_F_ARENA_SCALAR | 2975 BPF_F_TOKEN_FD)) 2976 return -EINVAL; 2977 2978 if ((attr->prog_flags & BPF_F_ARENA_SCALAR) && !bpf_jit_supports_arena_scalar()) 2979 return -EOPNOTSUPP; 2980 2981 bpf_prog_load_fixup_attach_type(attr); 2982 2983 if (attr->prog_flags & BPF_F_TOKEN_FD) { 2984 token = bpf_token_get_from_fd(attr->prog_token_fd); 2985 if (IS_ERR(token)) 2986 return PTR_ERR(token); 2987 /* if current token doesn't grant prog loading permissions, 2988 * then we can't use this token, so ignore it and rely on 2989 * system-wide capabilities checks 2990 */ 2991 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || 2992 !bpf_token_allow_prog_type(token, attr->prog_type, 2993 attr->expected_attach_type)) { 2994 bpf_token_put(token); 2995 token = NULL; 2996 } 2997 } 2998 2999 bpf_cap = bpf_token_capable(token, CAP_BPF); 3000 err = -EPERM; 3001 3002 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 3003 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 3004 !bpf_cap) 3005 goto put_token; 3006 3007 /* Intent here is for unprivileged_bpf_disabled to block BPF program 3008 * creation for unprivileged users; other actions depend 3009 * on fd availability and access to bpffs, so are dependent on 3010 * object creation success. Even with unprivileged BPF disabled, 3011 * capability checks are still carried out for these 3012 * and other operations. 3013 */ 3014 if (sysctl_unprivileged_bpf_disabled && !bpf_cap) 3015 goto put_token; 3016 3017 if (attr->insn_cnt == 0 || 3018 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { 3019 err = -E2BIG; 3020 goto put_token; 3021 } 3022 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 3023 type != BPF_PROG_TYPE_CGROUP_SKB && 3024 !bpf_cap) 3025 goto put_token; 3026 3027 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) 3028 goto put_token; 3029 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) 3030 goto put_token; 3031 3032 multi_func = is_tracing_multi(attr->expected_attach_type); 3033 3034 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 3035 * or btf, we need to check which one it is 3036 */ 3037 if (attr->attach_prog_fd) { 3038 dst_prog = bpf_prog_get(attr->attach_prog_fd); 3039 if (IS_ERR(dst_prog)) { 3040 dst_prog = NULL; 3041 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 3042 if (IS_ERR(attach_btf)) { 3043 err = -EINVAL; 3044 goto put_token; 3045 } 3046 if (!btf_is_kernel(attach_btf)) { 3047 /* attaching through specifying bpf_prog's BTF 3048 * objects directly might be supported eventually 3049 */ 3050 btf_put(attach_btf); 3051 err = -ENOTSUPP; 3052 goto put_token; 3053 } 3054 } 3055 } else if (attr->attach_btf_id || multi_func) { 3056 /* fall back to vmlinux BTF, if BTF type ID is specified */ 3057 attach_btf = bpf_get_btf_vmlinux(); 3058 if (IS_ERR(attach_btf)) { 3059 err = PTR_ERR(attach_btf); 3060 goto put_token; 3061 } 3062 if (!attach_btf) { 3063 err = -EINVAL; 3064 goto put_token; 3065 } 3066 btf_get(attach_btf); 3067 } 3068 3069 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 3070 attach_btf, attr->attach_btf_id, 3071 dst_prog, multi_func)) { 3072 if (dst_prog) 3073 bpf_prog_put(dst_prog); 3074 if (attach_btf) 3075 btf_put(attach_btf); 3076 err = -EINVAL; 3077 goto put_token; 3078 } 3079 3080 /* plain bpf_prog allocation */ 3081 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 3082 if (!prog) { 3083 if (dst_prog) 3084 bpf_prog_put(dst_prog); 3085 if (attach_btf) 3086 btf_put(attach_btf); 3087 err = -EINVAL; 3088 goto put_token; 3089 } 3090 3091 prog->expected_attach_type = attr->expected_attach_type; 3092 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); 3093 prog->aux->attach_btf = attach_btf; 3094 prog->aux->attach_btf_id = multi_func ? bpf_multi_func_btf_id[0] : attr->attach_btf_id; 3095 prog->aux->dst_prog = dst_prog; 3096 if (dst_prog) { 3097 prog->aux->saved_dst_prog_type = dst_prog->type; 3098 prog->aux->saved_dst_attach_type = dst_prog->expected_attach_type; 3099 } 3100 prog->aux->dev_bound = !!attr->prog_ifindex; 3101 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 3102 3103 /* move token into prog->aux, reuse taken refcnt */ 3104 prog->aux->token = token; 3105 token = NULL; 3106 3107 prog->aux->user = get_current_user(); 3108 prog->len = attr->insn_cnt; 3109 3110 err = bpf_prog_stream_init(prog, GFP_USER); 3111 if (err) 3112 goto free_prog; 3113 3114 err = -EFAULT; 3115 if (copy_from_bpfptr(prog->insns, 3116 make_bpfptr(attr->insns, uattr.is_kernel), 3117 bpf_prog_insn_size(prog)) != 0) 3118 goto free_prog; 3119 /* copy eBPF program license from user space */ 3120 if (strncpy_from_bpfptr(license, 3121 make_bpfptr(attr->license, uattr.is_kernel), 3122 sizeof(license) - 1) < 0) 3123 goto free_prog; 3124 license[sizeof(license) - 1] = 0; 3125 3126 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 3127 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; 3128 prog->aux->sig.keyring_type = BPF_SIG_KEYRING_NONE; 3129 prog->aux->sig.verdict = BPF_SIG_UNSIGNED; 3130 prog->orig_prog = NULL; 3131 prog->jited = 0; 3132 3133 atomic64_set(&prog->aux->refcnt, 1); 3134 3135 if (bpf_prog_is_dev_bound(prog->aux)) { 3136 err = bpf_prog_dev_bound_init(prog, attr); 3137 if (err) 3138 goto free_prog; 3139 } 3140 3141 if (type == BPF_PROG_TYPE_EXT && dst_prog && 3142 bpf_prog_is_dev_bound(dst_prog->aux)) { 3143 err = bpf_prog_dev_bound_inherit(prog, dst_prog); 3144 if (err) 3145 goto free_prog; 3146 } 3147 3148 /* 3149 * Bookkeeping for managing the program attachment chain. 3150 * 3151 * It might be tempting to set attach_tracing_prog flag at the attachment 3152 * time, but this will not prevent from loading bunch of tracing prog 3153 * first, then attach them one to another. 3154 * 3155 * The flag attach_tracing_prog is set for the whole program lifecycle, and 3156 * doesn't have to be cleared in bpf_tracing_link_release, since tracing 3157 * programs cannot change attachment target. 3158 */ 3159 if (type == BPF_PROG_TYPE_TRACING && dst_prog && 3160 dst_prog->type == BPF_PROG_TYPE_TRACING) { 3161 prog->aux->attach_tracing_prog = true; 3162 } 3163 3164 /* find program type: socket_filter vs tracing_filter */ 3165 err = find_prog_type(type, prog); 3166 if (err < 0) 3167 goto free_prog; 3168 3169 prog->aux->load_time = ktime_get_boottime_ns(); 3170 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 3171 sizeof(attr->prog_name)); 3172 if (err < 0) 3173 goto free_prog; 3174 3175 /* run eBPF verifier */ 3176 err = bpf_check(&prog, attr, uattr, attr_log); 3177 if (err < 0) 3178 goto free_used_maps; 3179 3180 err = bpf_prog_mark_insn_arrays_ready(prog); 3181 if (err < 0) 3182 goto free_used_maps; 3183 3184 err = bpf_prog_alloc_id(prog); 3185 if (err) 3186 goto free_used_maps; 3187 3188 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 3189 * effectively publicly exposed. However, retrieving via 3190 * bpf_prog_get_fd_by_id() will take another reference, 3191 * therefore it cannot be gone underneath us. 3192 * 3193 * Only for the time /after/ successful bpf_prog_new_fd() 3194 * and before returning to userspace, we might just hold 3195 * one reference and any parallel close on that fd could 3196 * rip everything out. Hence, below notifications must 3197 * happen before bpf_prog_new_fd(). 3198 * 3199 * Also, any failure handling from this point onwards must 3200 * be using bpf_prog_put() given the program is exposed. 3201 */ 3202 bpf_prog_kallsyms_add(prog); 3203 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 3204 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 3205 3206 err = bpf_prog_new_fd(prog); 3207 if (err < 0) 3208 bpf_prog_put(prog); 3209 return err; 3210 3211 free_used_maps: 3212 /* In case we have subprogs, we need to wait for a grace 3213 * period before we can tear down JIT memory since symbols 3214 * are already exposed under kallsyms. 3215 */ 3216 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); 3217 return err; 3218 3219 free_prog: 3220 free_uid(prog->aux->user); 3221 if (prog->aux->attach_btf) 3222 btf_put(prog->aux->attach_btf); 3223 bpf_prog_free(prog); 3224 put_token: 3225 bpf_token_put(token); 3226 return err; 3227 } 3228 3229 #define BPF_OBJ_LAST_FIELD path_fd 3230 3231 static int bpf_obj_pin(const union bpf_attr *attr) 3232 { 3233 int path_fd; 3234 3235 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) 3236 return -EINVAL; 3237 3238 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3239 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3240 return -EINVAL; 3241 3242 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3243 return bpf_obj_pin_user(attr->bpf_fd, path_fd, 3244 u64_to_user_ptr(attr->pathname)); 3245 } 3246 3247 static int bpf_obj_get(const union bpf_attr *attr) 3248 { 3249 int path_fd; 3250 3251 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 3252 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) 3253 return -EINVAL; 3254 3255 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3256 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3257 return -EINVAL; 3258 3259 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3260 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), 3261 attr->file_flags); 3262 } 3263 3264 /* bpf_link_init_sleepable() allows to specify whether BPF link itself has 3265 * "sleepable" semantics, which normally would mean that BPF link's attach 3266 * hook can dereference link or link's underlying program for some time after 3267 * detachment due to RCU Tasks Trace-based lifetime protection scheme. 3268 * BPF program itself can be non-sleepable, yet, because it's transitively 3269 * reachable through BPF link, its freeing has to be delayed until after RCU 3270 * Tasks Trace GP. 3271 */ 3272 void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type, 3273 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3274 enum bpf_attach_type attach_type, bool sleepable) 3275 { 3276 WARN_ON(ops->dealloc && ops->dealloc_deferred); 3277 atomic64_set(&link->refcnt, 1); 3278 link->type = type; 3279 link->sleepable = sleepable; 3280 link->id = 0; 3281 link->ops = ops; 3282 link->prog = prog; 3283 link->attach_type = attach_type; 3284 } 3285 3286 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 3287 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3288 enum bpf_attach_type attach_type) 3289 { 3290 bpf_link_init_sleepable(link, type, ops, prog, attach_type, false); 3291 } 3292 3293 void bpf_tramp_link_init(struct bpf_tramp_link *link, enum bpf_link_type type, 3294 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3295 enum bpf_attach_type attach_type, u64 cookie) 3296 { 3297 bpf_link_init(&link->link, type, ops, prog, attach_type); 3298 link->node.link = &link->link; 3299 link->node.cookie = cookie; 3300 } 3301 3302 static void bpf_link_free_id(int id) 3303 { 3304 if (!id) 3305 return; 3306 3307 spin_lock_bh(&link_idr_lock); 3308 idr_remove(&link_idr, id); 3309 spin_unlock_bh(&link_idr_lock); 3310 } 3311 3312 /* Clean up bpf_link and corresponding anon_inode file and FD. After 3313 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 3314 * anon_inode's release() call. This helper marks bpf_link as 3315 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 3316 * is not decremented, it's the responsibility of a calling code that failed 3317 * to complete bpf_link initialization. 3318 * This helper eventually calls link's dealloc callback, but does not call 3319 * link's release callback. 3320 */ 3321 void bpf_link_cleanup(struct bpf_link_primer *primer) 3322 { 3323 primer->link->prog = NULL; 3324 bpf_link_free_id(primer->id); 3325 fput(primer->file); 3326 put_unused_fd(primer->fd); 3327 } 3328 3329 void bpf_link_inc(struct bpf_link *link) 3330 { 3331 atomic64_inc(&link->refcnt); 3332 } 3333 3334 static void bpf_link_dealloc(struct bpf_link *link) 3335 { 3336 /* now that we know that bpf_link itself can't be reached, put underlying BPF program */ 3337 if (link->prog) 3338 bpf_prog_put(link->prog); 3339 3340 /* free bpf_link and its containing memory */ 3341 if (link->ops->dealloc_deferred) 3342 link->ops->dealloc_deferred(link); 3343 else 3344 link->ops->dealloc(link); 3345 } 3346 3347 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) 3348 { 3349 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); 3350 3351 bpf_link_dealloc(link); 3352 } 3353 3354 static bool bpf_link_is_tracepoint(struct bpf_link *link) 3355 { 3356 /* 3357 * Only these combinations support a tracepoint bpf_link. 3358 * BPF_LINK_TYPE_TRACING raw_tp progs are hardcoded to use 3359 * bpf_raw_tp_link_lops and thus dealloc_deferred(), see 3360 * bpf_raw_tp_link_attach(). 3361 */ 3362 return link->type == BPF_LINK_TYPE_RAW_TRACEPOINT || 3363 (link->type == BPF_LINK_TYPE_TRACING && link->attach_type == BPF_TRACE_RAW_TP); 3364 } 3365 3366 /* bpf_link_free is guaranteed to be called from process context */ 3367 static void bpf_link_free(struct bpf_link *link) 3368 { 3369 const struct bpf_link_ops *ops = link->ops; 3370 3371 bpf_link_free_id(link->id); 3372 /* detach BPF program, clean up used resources */ 3373 if (link->prog) 3374 ops->release(link); 3375 if (ops->dealloc_deferred) { 3376 /* 3377 * Schedule BPF link deallocation, which will only then 3378 * trigger putting BPF program refcount. 3379 * If underlying BPF program is sleepable or BPF link's target 3380 * attach hookpoint is sleepable or otherwise requires RCU GPs 3381 * to ensure link and its underlying BPF program is not 3382 * reachable anymore, we need to first wait for RCU tasks 3383 * trace sync, and then go through "classic" RCU grace period. 3384 * 3385 * For tracepoint BPF links, we need to go through SRCU grace 3386 * period wait instead when non-faultable tracepoint is used. We 3387 * don't need to chain SRCU grace period waits, however, for the 3388 * faultable case, since it exclusively uses RCU Tasks Trace. 3389 */ 3390 if (link->sleepable || (link->prog && link->prog->sleepable)) 3391 /* RCU Tasks Trace grace period implies RCU grace period. */ 3392 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3393 /* We need to do a SRCU grace period wait for non-faultable tracepoint BPF links. */ 3394 else if (bpf_link_is_tracepoint(link)) 3395 call_tracepoint_unregister_atomic(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3396 else 3397 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3398 } else if (ops->dealloc) { 3399 bpf_link_dealloc(link); 3400 } 3401 } 3402 3403 static void bpf_link_put_deferred(struct work_struct *work) 3404 { 3405 struct bpf_link *link = container_of(work, struct bpf_link, work); 3406 3407 bpf_link_free(link); 3408 } 3409 3410 /* bpf_link_put might be called from atomic context. It needs to be called 3411 * from sleepable context in order to acquire sleeping locks during the process. 3412 */ 3413 void bpf_link_put(struct bpf_link *link) 3414 { 3415 if (!atomic64_dec_and_test(&link->refcnt)) 3416 return; 3417 3418 INIT_WORK(&link->work, bpf_link_put_deferred); 3419 schedule_work(&link->work); 3420 } 3421 EXPORT_SYMBOL(bpf_link_put); 3422 3423 static void bpf_link_put_direct(struct bpf_link *link) 3424 { 3425 if (!atomic64_dec_and_test(&link->refcnt)) 3426 return; 3427 bpf_link_free(link); 3428 } 3429 3430 static int bpf_link_release(struct inode *inode, struct file *filp) 3431 { 3432 struct bpf_link *link = filp->private_data; 3433 3434 bpf_link_put_direct(link); 3435 return 0; 3436 } 3437 3438 #ifdef CONFIG_PROC_FS 3439 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 3440 #define BPF_MAP_TYPE(_id, _ops) 3441 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 3442 static const char *bpf_link_type_strs[] = { 3443 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 3444 #include <linux/bpf_types.h> 3445 }; 3446 #undef BPF_PROG_TYPE 3447 #undef BPF_MAP_TYPE 3448 #undef BPF_LINK_TYPE 3449 3450 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 3451 { 3452 const struct bpf_link *link = filp->private_data; 3453 const struct bpf_prog *prog; 3454 enum bpf_link_type type = link->type; 3455 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 3456 u32 prog_id = 0; 3457 3458 if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) { 3459 if (link->type == BPF_LINK_TYPE_KPROBE_MULTI) 3460 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_KPROBE_MULTI_RETURN ? 3461 "kretprobe_multi" : "kprobe_multi"); 3462 else if (link->type == BPF_LINK_TYPE_UPROBE_MULTI) 3463 seq_printf(m, "link_type:\t%s\n", link->flags & BPF_F_UPROBE_MULTI_RETURN ? 3464 "uretprobe_multi" : "uprobe_multi"); 3465 else 3466 seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]); 3467 } else { 3468 WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type); 3469 seq_printf(m, "link_type:\t<%u>\n", type); 3470 } 3471 seq_printf(m, "link_id:\t%u\n", link->id); 3472 3473 rcu_read_lock(); 3474 prog = READ_ONCE(link->prog); 3475 if (prog) { 3476 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 3477 prog_id = prog->aux->id; 3478 } 3479 rcu_read_unlock(); 3480 3481 if (prog) { 3482 seq_printf(m, 3483 "prog_tag:\t%s\n" 3484 "prog_id:\t%u\n", 3485 prog_tag, 3486 prog_id); 3487 } 3488 if (link->ops->show_fdinfo) 3489 link->ops->show_fdinfo(link, m); 3490 } 3491 #endif 3492 3493 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts) 3494 { 3495 struct bpf_link *link = file->private_data; 3496 3497 return link->ops->poll(file, pts); 3498 } 3499 3500 static const struct file_operations bpf_link_fops = { 3501 #ifdef CONFIG_PROC_FS 3502 .show_fdinfo = bpf_link_show_fdinfo, 3503 #endif 3504 .release = bpf_link_release, 3505 .read = bpf_dummy_read, 3506 .write = bpf_dummy_write, 3507 }; 3508 3509 static const struct file_operations bpf_link_fops_poll = { 3510 #ifdef CONFIG_PROC_FS 3511 .show_fdinfo = bpf_link_show_fdinfo, 3512 #endif 3513 .release = bpf_link_release, 3514 .read = bpf_dummy_read, 3515 .write = bpf_dummy_write, 3516 .poll = bpf_link_poll, 3517 }; 3518 3519 static int bpf_link_alloc_id(struct bpf_link *link) 3520 { 3521 int id; 3522 3523 idr_preload(GFP_KERNEL); 3524 spin_lock_bh(&link_idr_lock); 3525 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 3526 spin_unlock_bh(&link_idr_lock); 3527 idr_preload_end(); 3528 3529 return id; 3530 } 3531 3532 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 3533 * reserving unused FD and allocating ID from link_idr. This is to be paired 3534 * with bpf_link_settle() to install FD and ID and expose bpf_link to 3535 * user-space, if bpf_link is successfully attached. If not, bpf_link and 3536 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 3537 * transient state is passed around in struct bpf_link_primer. 3538 * This is preferred way to create and initialize bpf_link, especially when 3539 * there are complicated and expensive operations in between creating bpf_link 3540 * itself and attaching it to BPF hook. By using bpf_link_prime() and 3541 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 3542 * expensive (and potentially failing) roll back operations in a rare case 3543 * that file, FD, or ID can't be allocated. 3544 */ 3545 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 3546 { 3547 struct file *file; 3548 int fd, id; 3549 3550 fd = get_unused_fd_flags(O_CLOEXEC); 3551 if (fd < 0) 3552 return fd; 3553 3554 id = bpf_link_alloc_id(link); 3555 if (id < 0) { 3556 put_unused_fd(fd); 3557 return id; 3558 } 3559 3560 file = anon_inode_getfile("bpf_link", 3561 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3562 link, O_CLOEXEC); 3563 if (IS_ERR(file)) { 3564 bpf_link_free_id(id); 3565 put_unused_fd(fd); 3566 return PTR_ERR(file); 3567 } 3568 3569 primer->link = link; 3570 primer->file = file; 3571 primer->fd = fd; 3572 primer->id = id; 3573 return 0; 3574 } 3575 3576 int bpf_link_settle(struct bpf_link_primer *primer) 3577 { 3578 /* make bpf_link fetchable by ID */ 3579 spin_lock_bh(&link_idr_lock); 3580 primer->link->id = primer->id; 3581 spin_unlock_bh(&link_idr_lock); 3582 /* make bpf_link fetchable by FD */ 3583 fd_install(primer->fd, primer->file); 3584 /* pass through installed FD */ 3585 return primer->fd; 3586 } 3587 3588 int bpf_link_new_fd(struct bpf_link *link) 3589 { 3590 return anon_inode_getfd("bpf-link", 3591 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3592 link, O_CLOEXEC); 3593 } 3594 3595 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 3596 { 3597 CLASS(fd, f)(ufd); 3598 struct bpf_link *link; 3599 3600 if (fd_empty(f)) 3601 return ERR_PTR(-EBADF); 3602 if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll) 3603 return ERR_PTR(-EINVAL); 3604 3605 link = fd_file(f)->private_data; 3606 bpf_link_inc(link); 3607 return link; 3608 } 3609 EXPORT_SYMBOL_NS(bpf_link_get_from_fd, "BPF_INTERNAL"); 3610 3611 static void bpf_tracing_link_release(struct bpf_link *link) 3612 { 3613 struct bpf_tracing_link *tr_link = 3614 container_of(link, struct bpf_tracing_link, link.link); 3615 int err; 3616 3617 err = bpf_trampoline_unlink_prog(&tr_link->link.node, 3618 tr_link->trampoline, 3619 tr_link->tgt_prog); 3620 WARN_ONCE(err, "bpf_trampoline_unlink_prog failed: %d\n", err); 3621 3622 bpf_trampoline_put(tr_link->trampoline); 3623 3624 /* tgt_prog is NULL if target is a kernel function */ 3625 if (tr_link->tgt_prog) 3626 bpf_prog_put(tr_link->tgt_prog); 3627 } 3628 3629 static void bpf_tracing_link_dealloc(struct bpf_link *link) 3630 { 3631 struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link); 3632 3633 kfree(tr_link); 3634 } 3635 3636 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 3637 struct seq_file *seq) 3638 { 3639 struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link); 3640 3641 u32 target_btf_id, target_obj_id; 3642 3643 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3644 &target_obj_id, &target_btf_id); 3645 seq_printf(seq, 3646 "attach_type:\t%d\n" 3647 "target_obj_id:\t%u\n" 3648 "target_btf_id:\t%u\n" 3649 "cookie:\t%llu\n", 3650 link->attach_type, 3651 target_obj_id, 3652 target_btf_id, 3653 tr_link->link.node.cookie); 3654 } 3655 3656 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 3657 struct bpf_link_info *info) 3658 { 3659 struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link); 3660 3661 info->tracing.attach_type = link->attach_type; 3662 info->tracing.cookie = tr_link->link.node.cookie; 3663 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3664 &info->tracing.target_obj_id, 3665 &info->tracing.target_btf_id); 3666 3667 return 0; 3668 } 3669 3670 static const struct bpf_link_ops bpf_tracing_link_lops = { 3671 .release = bpf_tracing_link_release, 3672 .dealloc = bpf_tracing_link_dealloc, 3673 .show_fdinfo = bpf_tracing_link_show_fdinfo, 3674 .fill_link_info = bpf_tracing_link_fill_link_info, 3675 }; 3676 3677 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 3678 int tgt_prog_fd, 3679 u32 btf_id, 3680 u64 bpf_cookie, 3681 enum bpf_attach_type attach_type) 3682 { 3683 struct bpf_link_primer link_primer; 3684 struct bpf_prog *tgt_prog = NULL; 3685 struct bpf_trampoline *tr = NULL; 3686 struct bpf_tracing_link *link; 3687 u64 key = 0; 3688 int err; 3689 3690 switch (prog->type) { 3691 case BPF_PROG_TYPE_TRACING: 3692 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 3693 prog->expected_attach_type != BPF_TRACE_FEXIT && 3694 prog->expected_attach_type != BPF_TRACE_FSESSION && 3695 prog->expected_attach_type != BPF_MODIFY_RETURN) { 3696 err = -EINVAL; 3697 goto out_put_prog; 3698 } 3699 break; 3700 case BPF_PROG_TYPE_EXT: 3701 if (prog->expected_attach_type != 0) { 3702 err = -EINVAL; 3703 goto out_put_prog; 3704 } 3705 break; 3706 case BPF_PROG_TYPE_LSM: 3707 if (prog->expected_attach_type != BPF_LSM_MAC) { 3708 err = -EINVAL; 3709 goto out_put_prog; 3710 } 3711 break; 3712 default: 3713 err = -EINVAL; 3714 goto out_put_prog; 3715 } 3716 3717 if (!!tgt_prog_fd != !!btf_id) { 3718 err = -EINVAL; 3719 goto out_put_prog; 3720 } 3721 3722 if (tgt_prog_fd) { 3723 /* 3724 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this 3725 * part would be changed to implement the same for 3726 * BPF_PROG_TYPE_TRACING, do not forget to update the way how 3727 * attach_tracing_prog flag is set. 3728 */ 3729 if (prog->type != BPF_PROG_TYPE_EXT) { 3730 err = -EINVAL; 3731 goto out_put_prog; 3732 } 3733 3734 tgt_prog = bpf_prog_get(tgt_prog_fd); 3735 if (IS_ERR(tgt_prog)) { 3736 err = PTR_ERR(tgt_prog); 3737 tgt_prog = NULL; 3738 goto out_put_prog; 3739 } 3740 3741 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 3742 } 3743 3744 link = kzalloc_obj(*link, GFP_USER); 3745 if (!link) { 3746 err = -ENOMEM; 3747 goto out_put_prog; 3748 } 3749 bpf_tramp_link_init(&link->link, BPF_LINK_TYPE_TRACING, 3750 &bpf_tracing_link_lops, prog, attach_type, bpf_cookie); 3751 3752 if (prog->expected_attach_type == BPF_TRACE_FSESSION) { 3753 link->fexit.link = &link->link.link; 3754 link->fexit.cookie = bpf_cookie; 3755 } 3756 3757 mutex_lock(&prog->aux->dst_mutex); 3758 3759 /* There are a few possible cases here: 3760 * 3761 * - if prog->aux->dst_trampoline is set, the program was just loaded 3762 * and not yet attached to anything, so we can use the values stored 3763 * in prog->aux 3764 * 3765 * - if prog->aux->dst_trampoline is NULL, the program has already been 3766 * attached to a target and its initial target was cleared (below) 3767 * 3768 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 3769 * target_btf_id using the link_create API. 3770 * 3771 * - if tgt_prog == NULL when this function was called using the old 3772 * raw_tracepoint_open API, and we need a target from prog->aux 3773 * 3774 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 3775 * was detached and is going for re-attachment. 3776 * 3777 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf 3778 * are NULL, then program was already attached and user did not provide 3779 * tgt_prog_fd so we have no way to find out or create trampoline 3780 */ 3781 if (!prog->aux->dst_trampoline && !tgt_prog) { 3782 /* 3783 * Allow re-attach for TRACING and LSM programs. If it's 3784 * currently linked, bpf_trampoline_link_prog will fail. 3785 * EXT programs need to specify tgt_prog_fd, so they 3786 * re-attach in separate code path. 3787 */ 3788 if (prog->type != BPF_PROG_TYPE_TRACING && 3789 prog->type != BPF_PROG_TYPE_LSM) { 3790 err = -EINVAL; 3791 goto out_unlock; 3792 } 3793 /* We can allow re-attach only if we have valid attach_btf. */ 3794 if (!prog->aux->attach_btf) { 3795 err = -EINVAL; 3796 goto out_unlock; 3797 } 3798 btf_id = prog->aux->attach_btf_id; 3799 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 3800 } 3801 3802 if (!prog->aux->dst_trampoline || 3803 (key && key != prog->aux->dst_trampoline->key)) { 3804 /* If there is no saved target, or the specified target is 3805 * different from the destination specified at load time, we 3806 * need a new trampoline and a check for compatibility 3807 */ 3808 struct bpf_attach_target_info tgt_info = {}; 3809 3810 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 3811 &tgt_info); 3812 if (err) 3813 goto out_unlock; 3814 3815 if (tgt_info.tgt_mod) { 3816 module_put(prog->aux->mod); 3817 prog->aux->mod = tgt_info.tgt_mod; 3818 } 3819 3820 tr = bpf_trampoline_get(key, &tgt_info); 3821 if (!tr) { 3822 err = -ENOMEM; 3823 goto out_unlock; 3824 } 3825 } else { 3826 /* The caller didn't specify a target, or the target was the 3827 * same as the destination supplied during program load. This 3828 * means we can reuse the trampoline and reference from program 3829 * load time, and there is no need to allocate a new one. This 3830 * can only happen once for any program, as the saved values in 3831 * prog->aux are cleared below. 3832 */ 3833 tr = prog->aux->dst_trampoline; 3834 tgt_prog = prog->aux->dst_prog; 3835 } 3836 /* 3837 * It is to prevent modifying struct pt_regs via kprobe_write_ctx=true 3838 * freplace prog. Without this check, kprobe_write_ctx=true freplace 3839 * prog is allowed to attach to kprobe_write_ctx=false kprobe prog, and 3840 * then modify the registers of the kprobe prog's target kernel 3841 * function. 3842 * 3843 * This also blocks the combination of uprobe+freplace, because it is 3844 * unable to recognize the use of the tgt_prog as an uprobe or a kprobe 3845 * by tgt_prog itself. At attach time, uprobe/kprobe is recognized by 3846 * the target perf event flags in __perf_event_set_bpf_prog(). 3847 */ 3848 if (prog->type == BPF_PROG_TYPE_EXT && 3849 prog->aux->kprobe_write_ctx != tgt_prog->aux->kprobe_write_ctx) { 3850 err = -EINVAL; 3851 goto out_unlock; 3852 } 3853 /* 3854 * The size of these contexts depends on what the program is attached 3855 * to, or run with. That is compared with max_ctx_offset of the program, 3856 * and nobody looks at the one of its extensions. 3857 */ 3858 if (prog->type == BPF_PROG_TYPE_EXT && 3859 (tgt_prog->type == BPF_PROG_TYPE_RAW_TRACEPOINT || 3860 tgt_prog->type == BPF_PROG_TYPE_TRACEPOINT || 3861 tgt_prog->type == BPF_PROG_TYPE_SYSCALL) && 3862 prog->aux->max_ctx_offset > tgt_prog->aux->max_ctx_offset) { 3863 err = -EINVAL; 3864 goto out_unlock; 3865 } 3866 3867 err = bpf_link_prime(&link->link.link, &link_primer); 3868 if (err) 3869 goto out_unlock; 3870 3871 err = bpf_trampoline_link_prog(&link->link.node, tr, tgt_prog); 3872 if (err) { 3873 bpf_link_cleanup(&link_primer); 3874 link = NULL; 3875 goto out_unlock; 3876 } 3877 3878 link->tgt_prog = tgt_prog; 3879 link->trampoline = tr; 3880 3881 /* Always clear the trampoline and target prog from prog->aux to make 3882 * sure the original attach destination is not kept alive after a 3883 * program is (re-)attached to another target. 3884 */ 3885 if (prog->aux->dst_prog && 3886 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 3887 /* got extra prog ref from syscall, or attaching to different prog */ 3888 bpf_prog_put(prog->aux->dst_prog); 3889 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 3890 /* we allocated a new trampoline, so free the old one */ 3891 bpf_trampoline_put(prog->aux->dst_trampoline); 3892 3893 prog->aux->dst_prog = NULL; 3894 prog->aux->dst_trampoline = NULL; 3895 mutex_unlock(&prog->aux->dst_mutex); 3896 3897 return bpf_link_settle(&link_primer); 3898 out_unlock: 3899 if (tr && tr != prog->aux->dst_trampoline) 3900 bpf_trampoline_put(tr); 3901 mutex_unlock(&prog->aux->dst_mutex); 3902 kfree(link); 3903 out_put_prog: 3904 if (tgt_prog_fd && tgt_prog) 3905 bpf_prog_put(tgt_prog); 3906 return err; 3907 } 3908 3909 static void bpf_raw_tp_link_release(struct bpf_link *link) 3910 { 3911 struct bpf_raw_tp_link *raw_tp = 3912 container_of(link, struct bpf_raw_tp_link, link); 3913 3914 bpf_probe_unregister(raw_tp->btp, raw_tp); 3915 bpf_put_raw_tracepoint(raw_tp->btp); 3916 } 3917 3918 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 3919 { 3920 struct bpf_raw_tp_link *raw_tp = 3921 container_of(link, struct bpf_raw_tp_link, link); 3922 3923 kfree(raw_tp); 3924 } 3925 3926 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 3927 struct seq_file *seq) 3928 { 3929 struct bpf_raw_tp_link *raw_tp_link = 3930 container_of(link, struct bpf_raw_tp_link, link); 3931 3932 seq_printf(seq, 3933 "tp_name:\t%s\n" 3934 "cookie:\t%llu\n", 3935 raw_tp_link->btp->tp->name, 3936 raw_tp_link->cookie); 3937 } 3938 3939 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, 3940 u32 len) 3941 { 3942 if (ulen >= len + 1) { 3943 if (copy_to_user(ubuf, buf, len + 1)) 3944 return -EFAULT; 3945 } else { 3946 char zero = '\0'; 3947 3948 if (copy_to_user(ubuf, buf, ulen - 1)) 3949 return -EFAULT; 3950 if (put_user(zero, ubuf + ulen - 1)) 3951 return -EFAULT; 3952 return -ENOSPC; 3953 } 3954 3955 return 0; 3956 } 3957 3958 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 3959 struct bpf_link_info *info) 3960 { 3961 struct bpf_raw_tp_link *raw_tp_link = 3962 container_of(link, struct bpf_raw_tp_link, link); 3963 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 3964 const char *tp_name = raw_tp_link->btp->tp->name; 3965 u32 ulen = info->raw_tracepoint.tp_name_len; 3966 size_t tp_len = strlen(tp_name); 3967 3968 if (!ulen ^ !ubuf) 3969 return -EINVAL; 3970 3971 info->raw_tracepoint.tp_name_len = tp_len + 1; 3972 info->raw_tracepoint.cookie = raw_tp_link->cookie; 3973 3974 if (!ubuf) 3975 return 0; 3976 3977 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); 3978 } 3979 3980 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 3981 .release = bpf_raw_tp_link_release, 3982 .dealloc_deferred = bpf_raw_tp_link_dealloc, 3983 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 3984 .fill_link_info = bpf_raw_tp_link_fill_link_info, 3985 }; 3986 3987 #ifdef CONFIG_PERF_EVENTS 3988 struct bpf_perf_link { 3989 struct bpf_link link; 3990 struct file *perf_file; 3991 }; 3992 3993 static void bpf_perf_link_release(struct bpf_link *link) 3994 { 3995 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3996 struct perf_event *event = perf_link->perf_file->private_data; 3997 3998 perf_event_free_bpf_prog(event); 3999 fput(perf_link->perf_file); 4000 } 4001 4002 static void bpf_perf_link_dealloc(struct bpf_link *link) 4003 { 4004 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 4005 4006 kfree(perf_link); 4007 } 4008 4009 static int bpf_perf_link_fill_common(const struct perf_event *event, 4010 char __user *uname, u32 *ulenp, 4011 u64 *probe_offset, u64 *probe_addr, 4012 u32 *fd_type, unsigned long *missed) 4013 { 4014 const char *buf; 4015 u32 prog_id, ulen; 4016 size_t len; 4017 int err; 4018 4019 ulen = *ulenp; 4020 if (!ulen ^ !uname) 4021 return -EINVAL; 4022 4023 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, 4024 probe_offset, probe_addr, missed); 4025 if (err) 4026 return err; 4027 4028 if (buf) { 4029 len = strlen(buf); 4030 *ulenp = len + 1; 4031 } else { 4032 *ulenp = 1; 4033 } 4034 if (!uname) 4035 goto out; 4036 4037 if (buf) { 4038 err = bpf_copy_to_user(uname, buf, ulen, len); 4039 } else { 4040 char zero = '\0'; 4041 4042 if (put_user(zero, uname)) 4043 err = -EFAULT; 4044 } 4045 out: 4046 kfree_const(buf); 4047 return err; 4048 } 4049 4050 #ifdef CONFIG_KPROBE_EVENTS 4051 static int bpf_perf_link_fill_kprobe(const struct perf_event *event, 4052 struct bpf_link_info *info) 4053 { 4054 unsigned long missed; 4055 char __user *uname; 4056 u64 addr, offset; 4057 u32 ulen, type; 4058 int err; 4059 4060 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); 4061 ulen = info->perf_event.kprobe.name_len; 4062 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr, 4063 &type, &missed); 4064 if (err) 4065 return err; 4066 if (type == BPF_FD_TYPE_KRETPROBE) 4067 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; 4068 else 4069 info->perf_event.type = BPF_PERF_EVENT_KPROBE; 4070 info->perf_event.kprobe.name_len = ulen; 4071 info->perf_event.kprobe.offset = offset; 4072 info->perf_event.kprobe.missed = missed; 4073 if (!kallsyms_show_value(current_cred())) 4074 addr = 0; 4075 info->perf_event.kprobe.addr = addr; 4076 info->perf_event.kprobe.cookie = event->bpf_cookie; 4077 return 0; 4078 } 4079 4080 static void bpf_perf_link_fdinfo_kprobe(const struct perf_event *event, 4081 struct seq_file *seq) 4082 { 4083 const char *name; 4084 int err; 4085 u32 prog_id, type; 4086 u64 offset, addr; 4087 unsigned long missed; 4088 4089 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 4090 &offset, &addr, &missed); 4091 if (err) 4092 return; 4093 4094 seq_printf(seq, 4095 "name:\t%s\n" 4096 "offset:\t%#llx\n" 4097 "missed:\t%lu\n" 4098 "addr:\t%#llx\n" 4099 "event_type:\t%s\n" 4100 "cookie:\t%llu\n", 4101 name, offset, missed, addr, 4102 type == BPF_FD_TYPE_KRETPROBE ? "kretprobe" : "kprobe", 4103 event->bpf_cookie); 4104 kfree_const(name); 4105 } 4106 #endif 4107 4108 #ifdef CONFIG_UPROBE_EVENTS 4109 static int bpf_perf_link_fill_uprobe(const struct perf_event *event, 4110 struct bpf_link_info *info) 4111 { 4112 u64 ref_ctr_offset, offset; 4113 char __user *uname; 4114 u32 ulen, type; 4115 int err; 4116 4117 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); 4118 ulen = info->perf_event.uprobe.name_len; 4119 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &ref_ctr_offset, 4120 &type, NULL); 4121 if (err) 4122 return err; 4123 4124 if (type == BPF_FD_TYPE_URETPROBE) 4125 info->perf_event.type = BPF_PERF_EVENT_URETPROBE; 4126 else 4127 info->perf_event.type = BPF_PERF_EVENT_UPROBE; 4128 info->perf_event.uprobe.name_len = ulen; 4129 info->perf_event.uprobe.offset = offset; 4130 info->perf_event.uprobe.cookie = event->bpf_cookie; 4131 info->perf_event.uprobe.ref_ctr_offset = ref_ctr_offset; 4132 return 0; 4133 } 4134 4135 static void bpf_perf_link_fdinfo_uprobe(const struct perf_event *event, 4136 struct seq_file *seq) 4137 { 4138 const char *name; 4139 int err; 4140 u32 prog_id, type; 4141 u64 offset, ref_ctr_offset; 4142 unsigned long missed; 4143 4144 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 4145 &offset, &ref_ctr_offset, &missed); 4146 if (err) 4147 return; 4148 4149 seq_printf(seq, 4150 "name:\t%s\n" 4151 "offset:\t%#llx\n" 4152 "ref_ctr_offset:\t%#llx\n" 4153 "event_type:\t%s\n" 4154 "cookie:\t%llu\n", 4155 name, offset, ref_ctr_offset, 4156 type == BPF_FD_TYPE_URETPROBE ? "uretprobe" : "uprobe", 4157 event->bpf_cookie); 4158 kfree_const(name); 4159 } 4160 #endif 4161 4162 static int bpf_perf_link_fill_probe(const struct perf_event *event, 4163 struct bpf_link_info *info) 4164 { 4165 #ifdef CONFIG_KPROBE_EVENTS 4166 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 4167 return bpf_perf_link_fill_kprobe(event, info); 4168 #endif 4169 #ifdef CONFIG_UPROBE_EVENTS 4170 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 4171 return bpf_perf_link_fill_uprobe(event, info); 4172 #endif 4173 return -EOPNOTSUPP; 4174 } 4175 4176 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, 4177 struct bpf_link_info *info) 4178 { 4179 char __user *uname; 4180 u32 ulen; 4181 int err; 4182 4183 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); 4184 ulen = info->perf_event.tracepoint.name_len; 4185 err = bpf_perf_link_fill_common(event, uname, &ulen, NULL, NULL, NULL, NULL); 4186 if (err) 4187 return err; 4188 4189 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; 4190 info->perf_event.tracepoint.name_len = ulen; 4191 info->perf_event.tracepoint.cookie = event->bpf_cookie; 4192 return 0; 4193 } 4194 4195 static int bpf_perf_link_fill_perf_event(const struct perf_event *event, 4196 struct bpf_link_info *info) 4197 { 4198 info->perf_event.event.type = event->attr.type; 4199 info->perf_event.event.config = event->attr.config; 4200 info->perf_event.event.cookie = event->bpf_cookie; 4201 info->perf_event.type = BPF_PERF_EVENT_EVENT; 4202 return 0; 4203 } 4204 4205 static int bpf_perf_link_fill_link_info(const struct bpf_link *link, 4206 struct bpf_link_info *info) 4207 { 4208 struct bpf_perf_link *perf_link; 4209 const struct perf_event *event; 4210 4211 perf_link = container_of(link, struct bpf_perf_link, link); 4212 event = perf_get_event(perf_link->perf_file); 4213 if (IS_ERR(event)) 4214 return PTR_ERR(event); 4215 4216 switch (event->prog->type) { 4217 case BPF_PROG_TYPE_PERF_EVENT: 4218 return bpf_perf_link_fill_perf_event(event, info); 4219 case BPF_PROG_TYPE_TRACEPOINT: 4220 return bpf_perf_link_fill_tracepoint(event, info); 4221 case BPF_PROG_TYPE_KPROBE: 4222 return bpf_perf_link_fill_probe(event, info); 4223 default: 4224 return -EOPNOTSUPP; 4225 } 4226 } 4227 4228 static void bpf_perf_event_link_show_fdinfo(const struct perf_event *event, 4229 struct seq_file *seq) 4230 { 4231 seq_printf(seq, 4232 "type:\t%u\n" 4233 "config:\t%llu\n" 4234 "event_type:\t%s\n" 4235 "cookie:\t%llu\n", 4236 event->attr.type, event->attr.config, 4237 "event", event->bpf_cookie); 4238 } 4239 4240 static void bpf_tracepoint_link_show_fdinfo(const struct perf_event *event, 4241 struct seq_file *seq) 4242 { 4243 int err; 4244 const char *name; 4245 u32 prog_id; 4246 4247 err = bpf_get_perf_event_info(event, &prog_id, NULL, &name, NULL, 4248 NULL, NULL); 4249 if (err) 4250 return; 4251 4252 seq_printf(seq, 4253 "tp_name:\t%s\n" 4254 "event_type:\t%s\n" 4255 "cookie:\t%llu\n", 4256 name, "tracepoint", event->bpf_cookie); 4257 kfree_const(name); 4258 } 4259 4260 static void bpf_probe_link_show_fdinfo(const struct perf_event *event, 4261 struct seq_file *seq) 4262 { 4263 #ifdef CONFIG_KPROBE_EVENTS 4264 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 4265 return bpf_perf_link_fdinfo_kprobe(event, seq); 4266 #endif 4267 4268 #ifdef CONFIG_UPROBE_EVENTS 4269 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 4270 return bpf_perf_link_fdinfo_uprobe(event, seq); 4271 #endif 4272 } 4273 4274 static void bpf_perf_link_show_fdinfo(const struct bpf_link *link, 4275 struct seq_file *seq) 4276 { 4277 struct bpf_perf_link *perf_link; 4278 const struct perf_event *event; 4279 4280 perf_link = container_of(link, struct bpf_perf_link, link); 4281 event = perf_get_event(perf_link->perf_file); 4282 if (IS_ERR(event)) 4283 return; 4284 4285 switch (event->prog->type) { 4286 case BPF_PROG_TYPE_PERF_EVENT: 4287 return bpf_perf_event_link_show_fdinfo(event, seq); 4288 case BPF_PROG_TYPE_TRACEPOINT: 4289 return bpf_tracepoint_link_show_fdinfo(event, seq); 4290 case BPF_PROG_TYPE_KPROBE: 4291 return bpf_probe_link_show_fdinfo(event, seq); 4292 default: 4293 return; 4294 } 4295 } 4296 4297 static const struct bpf_link_ops bpf_perf_link_lops = { 4298 .release = bpf_perf_link_release, 4299 .dealloc = bpf_perf_link_dealloc, 4300 .fill_link_info = bpf_perf_link_fill_link_info, 4301 .show_fdinfo = bpf_perf_link_show_fdinfo, 4302 }; 4303 4304 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4305 { 4306 struct bpf_link_primer link_primer; 4307 struct bpf_perf_link *link; 4308 struct perf_event *event; 4309 struct file *perf_file; 4310 int err; 4311 4312 if (attr->link_create.flags) 4313 return -EINVAL; 4314 4315 perf_file = perf_event_get(attr->link_create.target_fd); 4316 if (IS_ERR(perf_file)) 4317 return PTR_ERR(perf_file); 4318 4319 link = kzalloc_obj(*link, GFP_USER); 4320 if (!link) { 4321 err = -ENOMEM; 4322 goto out_put_file; 4323 } 4324 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog, 4325 attr->link_create.attach_type); 4326 link->perf_file = perf_file; 4327 4328 err = bpf_link_prime(&link->link, &link_primer); 4329 if (err) { 4330 kfree(link); 4331 goto out_put_file; 4332 } 4333 4334 event = perf_file->private_data; 4335 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 4336 if (err) { 4337 bpf_link_cleanup(&link_primer); 4338 goto out_put_file; 4339 } 4340 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 4341 bpf_prog_inc(prog); 4342 4343 return bpf_link_settle(&link_primer); 4344 4345 out_put_file: 4346 fput(perf_file); 4347 return err; 4348 } 4349 #else 4350 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4351 { 4352 return -EOPNOTSUPP; 4353 } 4354 #endif /* CONFIG_PERF_EVENTS */ 4355 4356 static int bpf_raw_tp_link_attach(struct bpf_prog *prog, 4357 const char __user *user_tp_name, u64 cookie, 4358 enum bpf_attach_type attach_type) 4359 { 4360 struct bpf_link_primer link_primer; 4361 struct bpf_raw_tp_link *link; 4362 struct bpf_raw_event_map *btp; 4363 const char *tp_name; 4364 char buf[128]; 4365 int err; 4366 4367 switch (prog->type) { 4368 case BPF_PROG_TYPE_TRACING: 4369 case BPF_PROG_TYPE_EXT: 4370 case BPF_PROG_TYPE_LSM: 4371 if (user_tp_name) 4372 /* The attach point for this category of programs 4373 * should be specified via btf_id during program load. 4374 */ 4375 return -EINVAL; 4376 if (prog->type == BPF_PROG_TYPE_TRACING && 4377 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 4378 tp_name = prog->aux->attach_func_name; 4379 break; 4380 } 4381 return bpf_tracing_prog_attach(prog, 0, 0, 0, attach_type); 4382 case BPF_PROG_TYPE_RAW_TRACEPOINT: 4383 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 4384 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) 4385 return -EFAULT; 4386 buf[sizeof(buf) - 1] = 0; 4387 tp_name = buf; 4388 break; 4389 default: 4390 return -EINVAL; 4391 } 4392 4393 btp = bpf_get_raw_tracepoint(tp_name); 4394 if (!btp) 4395 return -ENOENT; 4396 4397 if (prog->sleepable && !tracepoint_is_faultable(btp->tp)) { 4398 bpf_put_raw_tracepoint(btp); 4399 return -EINVAL; 4400 } 4401 4402 link = kzalloc_obj(*link, GFP_USER); 4403 if (!link) { 4404 err = -ENOMEM; 4405 goto out_put_btp; 4406 } 4407 bpf_link_init_sleepable(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 4408 &bpf_raw_tp_link_lops, prog, attach_type, 4409 tracepoint_is_faultable(btp->tp)); 4410 link->btp = btp; 4411 link->cookie = cookie; 4412 4413 err = bpf_link_prime(&link->link, &link_primer); 4414 if (err) { 4415 kfree(link); 4416 goto out_put_btp; 4417 } 4418 4419 err = bpf_probe_register(link->btp, link); 4420 if (err) { 4421 bpf_link_cleanup(&link_primer); 4422 goto out_put_btp; 4423 } 4424 4425 return bpf_link_settle(&link_primer); 4426 4427 out_put_btp: 4428 bpf_put_raw_tracepoint(btp); 4429 return err; 4430 } 4431 4432 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie 4433 4434 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 4435 { 4436 struct bpf_prog *prog; 4437 void __user *tp_name; 4438 __u64 cookie; 4439 int fd; 4440 4441 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 4442 return -EINVAL; 4443 4444 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 4445 if (IS_ERR(prog)) 4446 return PTR_ERR(prog); 4447 4448 tp_name = u64_to_user_ptr(attr->raw_tracepoint.name); 4449 cookie = attr->raw_tracepoint.cookie; 4450 fd = bpf_raw_tp_link_attach(prog, tp_name, cookie, prog->expected_attach_type); 4451 if (fd < 0) 4452 bpf_prog_put(prog); 4453 return fd; 4454 } 4455 4456 static enum bpf_prog_type 4457 attach_type_to_prog_type(enum bpf_attach_type attach_type) 4458 { 4459 switch (attach_type) { 4460 case BPF_CGROUP_INET_INGRESS: 4461 case BPF_CGROUP_INET_EGRESS: 4462 return BPF_PROG_TYPE_CGROUP_SKB; 4463 case BPF_CGROUP_INET_SOCK_CREATE: 4464 case BPF_CGROUP_INET_SOCK_RELEASE: 4465 case BPF_CGROUP_INET4_POST_BIND: 4466 case BPF_CGROUP_INET6_POST_BIND: 4467 return BPF_PROG_TYPE_CGROUP_SOCK; 4468 case BPF_CGROUP_INET4_BIND: 4469 case BPF_CGROUP_INET6_BIND: 4470 case BPF_CGROUP_INET4_CONNECT: 4471 case BPF_CGROUP_INET6_CONNECT: 4472 case BPF_CGROUP_UNIX_CONNECT: 4473 case BPF_CGROUP_INET4_GETPEERNAME: 4474 case BPF_CGROUP_INET6_GETPEERNAME: 4475 case BPF_CGROUP_UNIX_GETPEERNAME: 4476 case BPF_CGROUP_INET4_GETSOCKNAME: 4477 case BPF_CGROUP_INET6_GETSOCKNAME: 4478 case BPF_CGROUP_UNIX_GETSOCKNAME: 4479 case BPF_CGROUP_UDP4_SENDMSG: 4480 case BPF_CGROUP_UDP6_SENDMSG: 4481 case BPF_CGROUP_UNIX_SENDMSG: 4482 case BPF_CGROUP_UDP4_RECVMSG: 4483 case BPF_CGROUP_UDP6_RECVMSG: 4484 case BPF_CGROUP_UNIX_RECVMSG: 4485 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 4486 case BPF_CGROUP_SOCK_OPS: 4487 return BPF_PROG_TYPE_SOCK_OPS; 4488 case BPF_CGROUP_DEVICE: 4489 return BPF_PROG_TYPE_CGROUP_DEVICE; 4490 case BPF_SK_MSG_VERDICT: 4491 return BPF_PROG_TYPE_SK_MSG; 4492 case BPF_SK_SKB_STREAM_PARSER: 4493 case BPF_SK_SKB_STREAM_VERDICT: 4494 case BPF_SK_SKB_VERDICT: 4495 return BPF_PROG_TYPE_SK_SKB; 4496 case BPF_LIRC_MODE2: 4497 return BPF_PROG_TYPE_LIRC_MODE2; 4498 case BPF_FLOW_DISSECTOR: 4499 return BPF_PROG_TYPE_FLOW_DISSECTOR; 4500 case BPF_CGROUP_SYSCTL: 4501 return BPF_PROG_TYPE_CGROUP_SYSCTL; 4502 case BPF_CGROUP_GETSOCKOPT: 4503 case BPF_CGROUP_SETSOCKOPT: 4504 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 4505 case BPF_TRACE_ITER: 4506 case BPF_TRACE_RAW_TP: 4507 case BPF_TRACE_FENTRY: 4508 case BPF_TRACE_FEXIT: 4509 case BPF_TRACE_FSESSION: 4510 case BPF_TRACE_FSESSION_MULTI: 4511 case BPF_TRACE_FENTRY_MULTI: 4512 case BPF_TRACE_FEXIT_MULTI: 4513 case BPF_MODIFY_RETURN: 4514 return BPF_PROG_TYPE_TRACING; 4515 case BPF_LSM_MAC: 4516 return BPF_PROG_TYPE_LSM; 4517 case BPF_SK_LOOKUP: 4518 return BPF_PROG_TYPE_SK_LOOKUP; 4519 case BPF_XDP: 4520 return BPF_PROG_TYPE_XDP; 4521 case BPF_LSM_CGROUP: 4522 return BPF_PROG_TYPE_LSM; 4523 case BPF_TCX_INGRESS: 4524 case BPF_TCX_EGRESS: 4525 case BPF_NETKIT_PRIMARY: 4526 case BPF_NETKIT_PEER: 4527 return BPF_PROG_TYPE_SCHED_CLS; 4528 default: 4529 return BPF_PROG_TYPE_UNSPEC; 4530 } 4531 } 4532 4533 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 4534 enum bpf_attach_type attach_type) 4535 { 4536 enum bpf_prog_type ptype; 4537 4538 switch (prog->type) { 4539 case BPF_PROG_TYPE_CGROUP_SOCK: 4540 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4541 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4542 case BPF_PROG_TYPE_SK_LOOKUP: 4543 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 4544 case BPF_PROG_TYPE_CGROUP_SKB: 4545 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) 4546 /* cg-skb progs can be loaded by unpriv user. 4547 * check permissions at attach time. 4548 */ 4549 return -EPERM; 4550 4551 ptype = attach_type_to_prog_type(attach_type); 4552 if (prog->type != ptype) 4553 return -EINVAL; 4554 4555 return prog->enforce_expected_attach_type && 4556 prog->expected_attach_type != attach_type ? 4557 -EINVAL : 0; 4558 case BPF_PROG_TYPE_EXT: 4559 return 0; 4560 case BPF_PROG_TYPE_NETFILTER: 4561 if (attach_type != BPF_NETFILTER) 4562 return -EINVAL; 4563 return 0; 4564 case BPF_PROG_TYPE_PERF_EVENT: 4565 case BPF_PROG_TYPE_TRACEPOINT: 4566 if (attach_type != BPF_PERF_EVENT) 4567 return -EINVAL; 4568 return 0; 4569 case BPF_PROG_TYPE_KPROBE: 4570 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && 4571 attach_type != BPF_TRACE_KPROBE_MULTI) 4572 return -EINVAL; 4573 if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION && 4574 attach_type != BPF_TRACE_KPROBE_SESSION) 4575 return -EINVAL; 4576 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && 4577 attach_type != BPF_TRACE_UPROBE_MULTI) 4578 return -EINVAL; 4579 if (prog->expected_attach_type == BPF_TRACE_UPROBE_SESSION && 4580 attach_type != BPF_TRACE_UPROBE_SESSION) 4581 return -EINVAL; 4582 if (attach_type != BPF_PERF_EVENT && 4583 attach_type != BPF_TRACE_KPROBE_MULTI && 4584 attach_type != BPF_TRACE_KPROBE_SESSION && 4585 attach_type != BPF_TRACE_UPROBE_MULTI && 4586 attach_type != BPF_TRACE_UPROBE_SESSION) 4587 return -EINVAL; 4588 return 0; 4589 case BPF_PROG_TYPE_SCHED_CLS: 4590 if (attach_type != BPF_TCX_INGRESS && 4591 attach_type != BPF_TCX_EGRESS && 4592 attach_type != BPF_NETKIT_PRIMARY && 4593 attach_type != BPF_NETKIT_PEER) 4594 return -EINVAL; 4595 return 0; 4596 default: 4597 ptype = attach_type_to_prog_type(attach_type); 4598 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) 4599 return -EINVAL; 4600 return 0; 4601 } 4602 } 4603 4604 static bool is_cgroup_prog_type(enum bpf_prog_type ptype, enum bpf_attach_type atype, 4605 bool check_atype) 4606 { 4607 switch (ptype) { 4608 case BPF_PROG_TYPE_CGROUP_DEVICE: 4609 case BPF_PROG_TYPE_CGROUP_SKB: 4610 case BPF_PROG_TYPE_CGROUP_SOCK: 4611 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4612 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4613 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4614 case BPF_PROG_TYPE_SOCK_OPS: 4615 return true; 4616 case BPF_PROG_TYPE_LSM: 4617 return check_atype ? atype == BPF_LSM_CGROUP : true; 4618 default: 4619 return false; 4620 } 4621 } 4622 4623 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision 4624 4625 #define BPF_F_ATTACH_MASK_BASE \ 4626 (BPF_F_ALLOW_OVERRIDE | \ 4627 BPF_F_ALLOW_MULTI | \ 4628 BPF_F_REPLACE | \ 4629 BPF_F_PREORDER) 4630 4631 #define BPF_F_ATTACH_MASK_MPROG \ 4632 (BPF_F_REPLACE | \ 4633 BPF_F_BEFORE | \ 4634 BPF_F_AFTER | \ 4635 BPF_F_ID | \ 4636 BPF_F_LINK) 4637 4638 static int bpf_prog_attach(const union bpf_attr *attr) 4639 { 4640 enum bpf_prog_type ptype; 4641 struct bpf_prog *prog; 4642 int ret; 4643 4644 if (CHECK_ATTR(BPF_PROG_ATTACH)) 4645 return -EINVAL; 4646 4647 ptype = attach_type_to_prog_type(attr->attach_type); 4648 if (ptype == BPF_PROG_TYPE_UNSPEC) 4649 return -EINVAL; 4650 if (bpf_mprog_supported(ptype)) { 4651 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4652 return -EINVAL; 4653 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4654 if (attr->attach_flags & ~(BPF_F_ATTACH_MASK_BASE | BPF_F_ATTACH_MASK_MPROG)) 4655 return -EINVAL; 4656 } else { 4657 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) 4658 return -EINVAL; 4659 if (attr->relative_fd || 4660 attr->expected_revision) 4661 return -EINVAL; 4662 } 4663 4664 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4665 if (IS_ERR(prog)) 4666 return PTR_ERR(prog); 4667 4668 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 4669 bpf_prog_put(prog); 4670 return -EINVAL; 4671 } 4672 4673 if (is_cgroup_prog_type(ptype, prog->expected_attach_type, true)) { 4674 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 4675 goto out; 4676 } 4677 4678 switch (ptype) { 4679 case BPF_PROG_TYPE_SK_SKB: 4680 case BPF_PROG_TYPE_SK_MSG: 4681 ret = sock_map_get_from_fd(attr, prog); 4682 break; 4683 case BPF_PROG_TYPE_LIRC_MODE2: 4684 ret = lirc_prog_attach(attr, prog); 4685 break; 4686 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4687 ret = netns_bpf_prog_attach(attr, prog); 4688 break; 4689 case BPF_PROG_TYPE_SCHED_CLS: 4690 if (attr->attach_type == BPF_TCX_INGRESS || 4691 attr->attach_type == BPF_TCX_EGRESS) 4692 ret = tcx_prog_attach(attr, prog); 4693 else 4694 ret = netkit_prog_attach(attr, prog); 4695 break; 4696 default: 4697 ret = -EINVAL; 4698 } 4699 out: 4700 if (ret) 4701 bpf_prog_put(prog); 4702 return ret; 4703 } 4704 4705 #define BPF_PROG_DETACH_LAST_FIELD expected_revision 4706 4707 static int bpf_prog_detach(const union bpf_attr *attr) 4708 { 4709 struct bpf_prog *prog = NULL; 4710 enum bpf_prog_type ptype; 4711 int ret; 4712 4713 if (CHECK_ATTR(BPF_PROG_DETACH)) 4714 return -EINVAL; 4715 4716 ptype = attach_type_to_prog_type(attr->attach_type); 4717 if (bpf_mprog_supported(ptype)) { 4718 if (ptype == BPF_PROG_TYPE_UNSPEC) 4719 return -EINVAL; 4720 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4721 return -EINVAL; 4722 if (attr->attach_bpf_fd) { 4723 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4724 if (IS_ERR(prog)) 4725 return PTR_ERR(prog); 4726 } else if (!bpf_mprog_detach_empty(ptype)) { 4727 return -EPERM; 4728 } 4729 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4730 if (attr->attach_flags || attr->relative_fd) 4731 return -EINVAL; 4732 } else if (attr->attach_flags || 4733 attr->relative_fd || 4734 attr->expected_revision) { 4735 return -EINVAL; 4736 } 4737 4738 switch (ptype) { 4739 case BPF_PROG_TYPE_SK_MSG: 4740 case BPF_PROG_TYPE_SK_SKB: 4741 ret = sock_map_prog_detach(attr, ptype); 4742 break; 4743 case BPF_PROG_TYPE_LIRC_MODE2: 4744 ret = lirc_prog_detach(attr); 4745 break; 4746 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4747 ret = netns_bpf_prog_detach(attr, ptype); 4748 break; 4749 case BPF_PROG_TYPE_CGROUP_DEVICE: 4750 case BPF_PROG_TYPE_CGROUP_SKB: 4751 case BPF_PROG_TYPE_CGROUP_SOCK: 4752 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4753 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4754 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4755 case BPF_PROG_TYPE_SOCK_OPS: 4756 case BPF_PROG_TYPE_LSM: 4757 ret = cgroup_bpf_prog_detach(attr, ptype); 4758 break; 4759 case BPF_PROG_TYPE_SCHED_CLS: 4760 if (attr->attach_type == BPF_TCX_INGRESS || 4761 attr->attach_type == BPF_TCX_EGRESS) 4762 ret = tcx_prog_detach(attr, prog); 4763 else 4764 ret = netkit_prog_detach(attr, prog); 4765 break; 4766 default: 4767 ret = -EINVAL; 4768 } 4769 4770 if (prog) 4771 bpf_prog_put(prog); 4772 return ret; 4773 } 4774 4775 #define BPF_PROG_QUERY_LAST_FIELD query.revision 4776 4777 static int bpf_prog_query(const union bpf_attr *attr, 4778 union bpf_attr __user *uattr, u32 uattr_size) 4779 { 4780 if (!bpf_net_capable()) 4781 return -EPERM; 4782 if (CHECK_ATTR(BPF_PROG_QUERY)) 4783 return -EINVAL; 4784 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 4785 return -EINVAL; 4786 4787 switch (attr->query.attach_type) { 4788 case BPF_CGROUP_INET_INGRESS: 4789 case BPF_CGROUP_INET_EGRESS: 4790 case BPF_CGROUP_INET_SOCK_CREATE: 4791 case BPF_CGROUP_INET_SOCK_RELEASE: 4792 case BPF_CGROUP_INET4_BIND: 4793 case BPF_CGROUP_INET6_BIND: 4794 case BPF_CGROUP_INET4_POST_BIND: 4795 case BPF_CGROUP_INET6_POST_BIND: 4796 case BPF_CGROUP_INET4_CONNECT: 4797 case BPF_CGROUP_INET6_CONNECT: 4798 case BPF_CGROUP_UNIX_CONNECT: 4799 case BPF_CGROUP_INET4_GETPEERNAME: 4800 case BPF_CGROUP_INET6_GETPEERNAME: 4801 case BPF_CGROUP_UNIX_GETPEERNAME: 4802 case BPF_CGROUP_INET4_GETSOCKNAME: 4803 case BPF_CGROUP_INET6_GETSOCKNAME: 4804 case BPF_CGROUP_UNIX_GETSOCKNAME: 4805 case BPF_CGROUP_UDP4_SENDMSG: 4806 case BPF_CGROUP_UDP6_SENDMSG: 4807 case BPF_CGROUP_UNIX_SENDMSG: 4808 case BPF_CGROUP_UDP4_RECVMSG: 4809 case BPF_CGROUP_UDP6_RECVMSG: 4810 case BPF_CGROUP_UNIX_RECVMSG: 4811 case BPF_CGROUP_SOCK_OPS: 4812 case BPF_CGROUP_DEVICE: 4813 case BPF_CGROUP_SYSCTL: 4814 case BPF_CGROUP_GETSOCKOPT: 4815 case BPF_CGROUP_SETSOCKOPT: 4816 case BPF_LSM_CGROUP: 4817 case BPF_STRUCT_OPS: 4818 return cgroup_bpf_prog_query(attr, uattr, uattr_size); 4819 case BPF_LIRC_MODE2: 4820 return lirc_prog_query(attr, uattr); 4821 case BPF_FLOW_DISSECTOR: 4822 case BPF_SK_LOOKUP: 4823 return netns_bpf_prog_query(attr, uattr); 4824 case BPF_SK_SKB_STREAM_PARSER: 4825 case BPF_SK_SKB_STREAM_VERDICT: 4826 case BPF_SK_MSG_VERDICT: 4827 case BPF_SK_SKB_VERDICT: 4828 return sock_map_bpf_prog_query(attr, uattr); 4829 case BPF_TCX_INGRESS: 4830 case BPF_TCX_EGRESS: 4831 return tcx_prog_query(attr, uattr); 4832 case BPF_NETKIT_PRIMARY: 4833 case BPF_NETKIT_PEER: 4834 return netkit_prog_query(attr, uattr); 4835 default: 4836 return -EINVAL; 4837 } 4838 } 4839 4840 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size 4841 4842 static int bpf_prog_test_run(const union bpf_attr *attr, 4843 union bpf_attr __user *uattr) 4844 { 4845 struct bpf_prog *prog; 4846 int ret = -ENOTSUPP; 4847 4848 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 4849 return -EINVAL; 4850 4851 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 4852 (!attr->test.ctx_size_in && attr->test.ctx_in)) 4853 return -EINVAL; 4854 4855 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 4856 (!attr->test.ctx_size_out && attr->test.ctx_out)) 4857 return -EINVAL; 4858 4859 prog = bpf_prog_get(attr->test.prog_fd); 4860 if (IS_ERR(prog)) 4861 return PTR_ERR(prog); 4862 4863 if (prog->aux->ops->test_run) 4864 ret = prog->aux->ops->test_run(prog, attr, uattr); 4865 4866 bpf_prog_put(prog); 4867 return ret; 4868 } 4869 4870 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 4871 4872 static int bpf_obj_get_next_id(const union bpf_attr *attr, 4873 union bpf_attr __user *uattr, 4874 struct idr *idr, 4875 spinlock_t *lock) 4876 { 4877 u32 next_id = attr->start_id; 4878 int err = 0; 4879 4880 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 4881 return -EINVAL; 4882 4883 if (!capable(CAP_SYS_ADMIN)) 4884 return -EPERM; 4885 4886 next_id++; 4887 spin_lock_bh(lock); 4888 if (!idr_get_next(idr, &next_id)) 4889 err = -ENOENT; 4890 spin_unlock_bh(lock); 4891 4892 if (!err) 4893 err = put_user(next_id, &uattr->next_id); 4894 4895 return err; 4896 } 4897 4898 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 4899 { 4900 struct bpf_map *map; 4901 4902 spin_lock_bh(&map_idr_lock); 4903 again: 4904 map = idr_get_next(&map_idr, id); 4905 if (map) { 4906 map = __bpf_map_inc_not_zero(map, false); 4907 if (IS_ERR(map)) { 4908 (*id)++; 4909 goto again; 4910 } 4911 } 4912 spin_unlock_bh(&map_idr_lock); 4913 4914 return map; 4915 } 4916 4917 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 4918 { 4919 struct bpf_prog *prog; 4920 4921 spin_lock_bh(&prog_idr_lock); 4922 again: 4923 prog = idr_get_next(&prog_idr, id); 4924 if (prog) { 4925 prog = bpf_prog_inc_not_zero(prog); 4926 if (IS_ERR(prog)) { 4927 (*id)++; 4928 goto again; 4929 } 4930 } 4931 spin_unlock_bh(&prog_idr_lock); 4932 4933 return prog; 4934 } 4935 4936 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 4937 4938 struct bpf_prog *bpf_prog_by_id(u32 id) 4939 { 4940 struct bpf_prog *prog; 4941 4942 if (!id) 4943 return ERR_PTR(-ENOENT); 4944 4945 spin_lock_bh(&prog_idr_lock); 4946 prog = idr_find(&prog_idr, id); 4947 if (prog) 4948 prog = bpf_prog_inc_not_zero(prog); 4949 else 4950 prog = ERR_PTR(-ENOENT); 4951 spin_unlock_bh(&prog_idr_lock); 4952 return prog; 4953 } 4954 4955 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 4956 { 4957 struct bpf_prog *prog; 4958 u32 id = attr->prog_id; 4959 int fd; 4960 4961 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 4962 return -EINVAL; 4963 4964 if (!capable(CAP_SYS_ADMIN)) 4965 return -EPERM; 4966 4967 prog = bpf_prog_by_id(id); 4968 if (IS_ERR(prog)) 4969 return PTR_ERR(prog); 4970 4971 fd = bpf_prog_new_fd(prog); 4972 if (fd < 0) 4973 bpf_prog_put(prog); 4974 4975 return fd; 4976 } 4977 4978 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 4979 4980 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 4981 { 4982 struct bpf_map *map; 4983 u32 id = attr->map_id; 4984 int f_flags; 4985 int fd; 4986 4987 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 4988 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 4989 return -EINVAL; 4990 4991 if (!capable(CAP_SYS_ADMIN)) 4992 return -EPERM; 4993 4994 f_flags = bpf_get_file_flag(attr->open_flags); 4995 if (f_flags < 0) 4996 return f_flags; 4997 4998 spin_lock_bh(&map_idr_lock); 4999 map = idr_find(&map_idr, id); 5000 if (map) 5001 map = __bpf_map_inc_not_zero(map, true); 5002 else 5003 map = ERR_PTR(-ENOENT); 5004 spin_unlock_bh(&map_idr_lock); 5005 5006 if (IS_ERR(map)) 5007 return PTR_ERR(map); 5008 5009 fd = bpf_map_new_fd(map, f_flags); 5010 if (fd < 0) 5011 bpf_map_put_with_uref(map); 5012 5013 return fd; 5014 } 5015 5016 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 5017 unsigned long addr, u32 *off, 5018 u32 *type) 5019 { 5020 const struct bpf_map *map; 5021 int i; 5022 5023 mutex_lock(&prog->aux->used_maps_mutex); 5024 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 5025 map = prog->aux->used_maps[i]; 5026 if (map == (void *)addr) { 5027 *type = BPF_PSEUDO_MAP_FD; 5028 goto out; 5029 } 5030 if (!map->ops->map_direct_value_meta) 5031 continue; 5032 if (!map->ops->map_direct_value_meta(map, addr, off)) { 5033 *type = BPF_PSEUDO_MAP_VALUE; 5034 goto out; 5035 } 5036 } 5037 map = NULL; 5038 5039 out: 5040 mutex_unlock(&prog->aux->used_maps_mutex); 5041 return map; 5042 } 5043 5044 static void prepare_dump_pseudo_call(struct bpf_insn *insn) 5045 { 5046 s32 call_off = insn->imm; 5047 5048 /* 5049 * BPF_CALL_ARGS only exists for interpreter fallback. 5050 * 1. For interpreter (BPF_CALL_ARGS): insn->off is the index of 5051 * interpreters_args array, so here using bpf_call_args_imm() 5052 * to get the real address offset. 5053 * 2. For JIT (BPF_CALL): insn->off is the subprog id. 5054 */ 5055 if (insn->code == (BPF_JMP | BPF_CALL_ARGS)) 5056 insn->imm = bpf_call_args_imm(insn->off); 5057 else 5058 insn->imm = insn->off; 5059 5060 /* Avoid dumping a truncated and misleading pc-relative offset. */ 5061 if (call_off > S16_MAX || call_off < S16_MIN) 5062 insn->off = 0; 5063 else 5064 insn->off = call_off; 5065 } 5066 5067 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 5068 const struct cred *f_cred) 5069 { 5070 const struct bpf_map *map; 5071 struct bpf_insn *insns; 5072 u32 off, type; 5073 u64 imm; 5074 u8 code; 5075 int i; 5076 5077 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 5078 GFP_USER); 5079 if (!insns) 5080 return insns; 5081 5082 for (i = 0; i < prog->len; i++) { 5083 code = insns[i].code; 5084 5085 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 5086 insns[i].code = BPF_JMP | BPF_CALL; 5087 insns[i].imm = BPF_FUNC_tail_call; 5088 /* fall-through */ 5089 } 5090 /* 5091 * BPF_JCOND is the same opcode as BPF_CALL_ARGS. The latter is for 5092 * the interpreter, and a prog with unwind_goto is always JITed. 5093 */ 5094 if (prog->jited && bpf_is_unwind_goto(&insns[i])) 5095 continue; 5096 if (code == (BPF_JMP | BPF_CALL) || 5097 code == (BPF_JMP | BPF_CALL_ARGS)) { 5098 /* Restore the legacy xlated dump layout. */ 5099 if (insns[i].src_reg == BPF_PSEUDO_CALL) 5100 prepare_dump_pseudo_call(&insns[i]); 5101 if (code == (BPF_JMP | BPF_CALL_ARGS)) 5102 insns[i].code = BPF_JMP | BPF_CALL; 5103 if (!bpf_dump_raw_ok(f_cred)) 5104 insns[i].imm = 0; 5105 continue; 5106 } 5107 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 5108 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 5109 continue; 5110 } 5111 5112 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || 5113 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { 5114 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; 5115 continue; 5116 } 5117 5118 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 5119 continue; 5120 5121 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 5122 map = bpf_map_from_imm(prog, imm, &off, &type); 5123 if (map) { 5124 insns[i].src_reg = type; 5125 insns[i].imm = map->id; 5126 insns[i + 1].imm = off; 5127 continue; 5128 } 5129 } 5130 5131 return insns; 5132 } 5133 5134 static int set_info_rec_size(struct bpf_prog_info *info) 5135 { 5136 /* 5137 * Ensure info.*_rec_size is the same as kernel expected size 5138 * 5139 * or 5140 * 5141 * Only allow zero *_rec_size if both _rec_size and _cnt are 5142 * zero. In this case, the kernel will set the expected 5143 * _rec_size back to the info. 5144 */ 5145 5146 if ((info->nr_func_info || info->func_info_rec_size) && 5147 info->func_info_rec_size != sizeof(struct bpf_func_info)) 5148 return -EINVAL; 5149 5150 if ((info->nr_line_info || info->line_info_rec_size) && 5151 info->line_info_rec_size != sizeof(struct bpf_line_info)) 5152 return -EINVAL; 5153 5154 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 5155 info->jited_line_info_rec_size != sizeof(__u64)) 5156 return -EINVAL; 5157 5158 info->func_info_rec_size = sizeof(struct bpf_func_info); 5159 info->line_info_rec_size = sizeof(struct bpf_line_info); 5160 info->jited_line_info_rec_size = sizeof(__u64); 5161 5162 return 0; 5163 } 5164 5165 static int bpf_prog_get_info_by_fd(struct file *file, 5166 struct bpf_prog *prog, 5167 const union bpf_attr *attr, 5168 union bpf_attr __user *uattr) 5169 { 5170 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5171 struct btf *attach_btf = bpf_prog_get_target_btf(prog); 5172 struct bpf_prog_info info; 5173 u32 info_len = attr->info.info_len; 5174 struct bpf_prog_kstats stats; 5175 char __user *uinsns; 5176 u32 ulen, len; 5177 int err; 5178 5179 len = offsetofend(struct bpf_prog_info, attach_btf_id); 5180 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), len, info_len); 5181 if (err) 5182 return err; 5183 info_len = min_t(u32, sizeof(info), info_len); 5184 5185 memset(&info, 0, sizeof(info)); 5186 if (copy_from_user(&info, uinfo, info_len)) 5187 return -EFAULT; 5188 5189 info.type = prog->type; 5190 info.id = prog->aux->id; 5191 info.load_time = prog->aux->load_time; 5192 info.created_by_uid = from_kuid_munged(current_user_ns(), 5193 prog->aux->user->uid); 5194 info.gpl_compatible = prog->gpl_compatible; 5195 5196 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 5197 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 5198 5199 mutex_lock(&prog->aux->used_maps_mutex); 5200 ulen = info.nr_map_ids; 5201 info.nr_map_ids = prog->aux->used_map_cnt; 5202 ulen = min_t(u32, info.nr_map_ids, ulen); 5203 if (ulen) { 5204 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 5205 u32 i; 5206 5207 for (i = 0; i < ulen; i++) 5208 if (put_user(prog->aux->used_maps[i]->id, 5209 &user_map_ids[i])) { 5210 mutex_unlock(&prog->aux->used_maps_mutex); 5211 return -EFAULT; 5212 } 5213 } 5214 mutex_unlock(&prog->aux->used_maps_mutex); 5215 5216 err = set_info_rec_size(&info); 5217 if (err) 5218 return err; 5219 5220 bpf_prog_get_stats(prog, &stats); 5221 info.run_time_ns = stats.nsecs; 5222 info.run_cnt = stats.cnt; 5223 info.recursion_misses = stats.misses; 5224 5225 info.verified_insns = prog->aux->verified_insns; 5226 if (prog->aux->btf) 5227 info.btf_id = btf_obj_id(prog->aux->btf); 5228 5229 if (!bpf_capable()) { 5230 info.jited_prog_len = 0; 5231 info.xlated_prog_len = 0; 5232 info.nr_jited_ksyms = 0; 5233 info.nr_jited_func_lens = 0; 5234 info.nr_func_info = 0; 5235 info.nr_line_info = 0; 5236 info.nr_jited_line_info = 0; 5237 goto done; 5238 } 5239 5240 ulen = info.xlated_prog_len; 5241 info.xlated_prog_len = bpf_prog_insn_size(prog); 5242 if (info.xlated_prog_len && ulen) { 5243 struct bpf_insn *insns_sanitized; 5244 bool fault; 5245 5246 if (!prog->blinded || bpf_dump_raw_ok(file->f_cred)) { 5247 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 5248 if (!insns_sanitized) 5249 return -ENOMEM; 5250 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 5251 ulen = min_t(u32, info.xlated_prog_len, ulen); 5252 fault = copy_to_user(uinsns, insns_sanitized, ulen); 5253 kfree(insns_sanitized); 5254 if (fault) 5255 return -EFAULT; 5256 } else { 5257 info.xlated_prog_insns = 0; 5258 } 5259 } 5260 5261 if (bpf_prog_is_offloaded(prog->aux)) { 5262 err = bpf_prog_offload_info_fill(&info, prog); 5263 if (err) 5264 return err; 5265 goto done; 5266 } 5267 5268 /* NOTE: the following code is supposed to be skipped for offload. 5269 * bpf_prog_offload_info_fill() is the place to fill similar fields 5270 * for offload. 5271 */ 5272 ulen = info.jited_prog_len; 5273 if (prog->aux->func_cnt) { 5274 u32 i; 5275 5276 info.jited_prog_len = 0; 5277 for (i = 0; i < prog->aux->func_cnt; i++) 5278 info.jited_prog_len += prog->aux->func[i]->jited_len; 5279 } else { 5280 info.jited_prog_len = prog->jited_len; 5281 } 5282 5283 if (info.jited_prog_len && ulen) { 5284 if (bpf_dump_raw_ok(file->f_cred)) { 5285 uinsns = u64_to_user_ptr(info.jited_prog_insns); 5286 ulen = min_t(u32, info.jited_prog_len, ulen); 5287 5288 /* for multi-function programs, copy the JITed 5289 * instructions for all the functions 5290 */ 5291 if (prog->aux->func_cnt) { 5292 u32 len, free, i; 5293 u8 *img; 5294 5295 free = ulen; 5296 for (i = 0; i < prog->aux->func_cnt; i++) { 5297 len = prog->aux->func[i]->jited_len; 5298 len = min_t(u32, len, free); 5299 img = (u8 *) prog->aux->func[i]->bpf_func; 5300 if (copy_to_user(uinsns, img, len)) 5301 return -EFAULT; 5302 uinsns += len; 5303 free -= len; 5304 if (!free) 5305 break; 5306 } 5307 } else { 5308 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 5309 return -EFAULT; 5310 } 5311 } else { 5312 info.jited_prog_insns = 0; 5313 } 5314 } 5315 5316 ulen = info.nr_jited_ksyms; 5317 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 5318 if (ulen) { 5319 if (bpf_dump_raw_ok(file->f_cred)) { 5320 unsigned long ksym_addr; 5321 u64 __user *user_ksyms; 5322 u32 i; 5323 5324 /* copy the address of the kernel symbol 5325 * corresponding to each function 5326 */ 5327 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 5328 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 5329 if (prog->aux->func_cnt) { 5330 for (i = 0; i < ulen; i++) { 5331 ksym_addr = (unsigned long) 5332 prog->aux->func[i]->bpf_func; 5333 if (put_user((u64) ksym_addr, 5334 &user_ksyms[i])) 5335 return -EFAULT; 5336 } 5337 } else { 5338 ksym_addr = (unsigned long) prog->bpf_func; 5339 if (put_user((u64) ksym_addr, &user_ksyms[0])) 5340 return -EFAULT; 5341 } 5342 } else { 5343 info.jited_ksyms = 0; 5344 } 5345 } 5346 5347 ulen = info.nr_jited_func_lens; 5348 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 5349 if (ulen) { 5350 if (bpf_dump_raw_ok(file->f_cred)) { 5351 u32 __user *user_lens; 5352 u32 func_len, i; 5353 5354 /* copy the JITed image lengths for each function */ 5355 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 5356 user_lens = u64_to_user_ptr(info.jited_func_lens); 5357 if (prog->aux->func_cnt) { 5358 for (i = 0; i < ulen; i++) { 5359 func_len = 5360 prog->aux->func[i]->jited_len; 5361 if (put_user(func_len, &user_lens[i])) 5362 return -EFAULT; 5363 } 5364 } else { 5365 func_len = prog->jited_len; 5366 if (put_user(func_len, &user_lens[0])) 5367 return -EFAULT; 5368 } 5369 } else { 5370 info.jited_func_lens = 0; 5371 } 5372 } 5373 5374 info.attach_btf_id = prog->aux->attach_btf_id; 5375 if (attach_btf) 5376 info.attach_btf_obj_id = btf_obj_id(attach_btf); 5377 5378 ulen = info.nr_func_info; 5379 info.nr_func_info = prog->aux->func_info_cnt; 5380 if (info.nr_func_info && ulen) { 5381 char __user *user_finfo; 5382 5383 user_finfo = u64_to_user_ptr(info.func_info); 5384 ulen = min_t(u32, info.nr_func_info, ulen); 5385 if (copy_to_user(user_finfo, prog->aux->func_info, 5386 info.func_info_rec_size * ulen)) 5387 return -EFAULT; 5388 } 5389 5390 ulen = info.nr_line_info; 5391 info.nr_line_info = prog->aux->nr_linfo; 5392 if (info.nr_line_info && ulen) { 5393 __u8 __user *user_linfo; 5394 5395 user_linfo = u64_to_user_ptr(info.line_info); 5396 ulen = min_t(u32, info.nr_line_info, ulen); 5397 if (copy_to_user(user_linfo, prog->aux->linfo, 5398 info.line_info_rec_size * ulen)) 5399 return -EFAULT; 5400 } 5401 5402 ulen = info.nr_jited_line_info; 5403 if (prog->aux->jited_linfo) 5404 info.nr_jited_line_info = prog->aux->nr_linfo; 5405 else 5406 info.nr_jited_line_info = 0; 5407 if (info.nr_jited_line_info && ulen) { 5408 if (bpf_dump_raw_ok(file->f_cred)) { 5409 unsigned long line_addr; 5410 __u64 __user *user_linfo; 5411 u32 i; 5412 5413 user_linfo = u64_to_user_ptr(info.jited_line_info); 5414 ulen = min_t(u32, info.nr_jited_line_info, ulen); 5415 for (i = 0; i < ulen; i++) { 5416 line_addr = (unsigned long)prog->aux->jited_linfo[i]; 5417 if (put_user((__u64)line_addr, &user_linfo[i])) 5418 return -EFAULT; 5419 } 5420 } else { 5421 info.jited_line_info = 0; 5422 } 5423 } 5424 5425 ulen = info.nr_prog_tags; 5426 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 5427 if (ulen) { 5428 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 5429 u32 i; 5430 5431 user_prog_tags = u64_to_user_ptr(info.prog_tags); 5432 ulen = min_t(u32, info.nr_prog_tags, ulen); 5433 if (prog->aux->func_cnt) { 5434 for (i = 0; i < ulen; i++) { 5435 if (copy_to_user(user_prog_tags[i], 5436 prog->aux->func[i]->tag, 5437 BPF_TAG_SIZE)) 5438 return -EFAULT; 5439 } 5440 } else { 5441 if (copy_to_user(user_prog_tags[0], 5442 prog->tag, BPF_TAG_SIZE)) 5443 return -EFAULT; 5444 } 5445 } 5446 5447 done: 5448 if (copy_to_user(uinfo, &info, info_len) || 5449 put_user(info_len, &uattr->info.info_len)) 5450 return -EFAULT; 5451 5452 return 0; 5453 } 5454 5455 static int bpf_map_get_info_by_fd(struct file *file, 5456 struct bpf_map *map, 5457 const union bpf_attr *attr, 5458 union bpf_attr __user *uattr) 5459 { 5460 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5461 struct bpf_map_info info; 5462 u32 info_len = attr->info.info_len, len; 5463 int err; 5464 5465 len = offsetofend(struct bpf_map_info, hash_size); 5466 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), len, info_len); 5467 if (err) 5468 return err; 5469 info_len = min_t(u32, sizeof(info), info_len); 5470 5471 memset(&info, 0, sizeof(info)); 5472 if (info_len >= offsetofend(struct bpf_map_info, hash) && 5473 get_user(info.hash, &uinfo->hash)) 5474 return -EFAULT; 5475 if (info_len >= offsetofend(struct bpf_map_info, hash_size) && 5476 get_user(info.hash_size, &uinfo->hash_size)) 5477 return -EFAULT; 5478 5479 info.type = map->map_type; 5480 info.id = map->id; 5481 info.key_size = map->key_size; 5482 info.value_size = map->value_size; 5483 info.max_entries = map->max_entries; 5484 info.map_flags = map->map_flags; 5485 info.map_extra = map->map_extra; 5486 memcpy(info.name, map->name, sizeof(map->name)); 5487 5488 if (map->btf) { 5489 info.btf_id = btf_obj_id(map->btf); 5490 info.btf_key_type_id = map->btf_key_type_id; 5491 info.btf_value_type_id = map->btf_value_type_id; 5492 } 5493 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 5494 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) 5495 bpf_map_struct_ops_info_fill(&info, map); 5496 5497 if (bpf_map_is_offloaded(map)) { 5498 err = bpf_map_offload_info_fill(&info, map); 5499 if (err) 5500 return err; 5501 } 5502 5503 if (info.hash) { 5504 char __user *uhash = u64_to_user_ptr(info.hash); 5505 5506 if (!map->ops->map_get_hash) 5507 return -EINVAL; 5508 if (info.hash_size != sizeof(map->sha)) 5509 return -EINVAL; 5510 if (!READ_ONCE(map->frozen)) 5511 return -EPERM; 5512 5513 err = map->ops->map_get_hash(map); 5514 if (err != 0) 5515 return err; 5516 5517 if (copy_to_user(uhash, map->sha, sizeof(map->sha)) != 0) 5518 return -EFAULT; 5519 } else if (info.hash_size) { 5520 return -EINVAL; 5521 } 5522 5523 if (copy_to_user(uinfo, &info, info_len) || 5524 put_user(info_len, &uattr->info.info_len)) 5525 return -EFAULT; 5526 5527 return 0; 5528 } 5529 5530 static int bpf_btf_get_info_by_fd(struct file *file, 5531 struct btf *btf, 5532 const union bpf_attr *attr, 5533 union bpf_attr __user *uattr) 5534 { 5535 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5536 u32 info_len = attr->info.info_len; 5537 int err; 5538 5539 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5540 if (err) 5541 return err; 5542 5543 return btf_get_info_by_fd(btf, attr, uattr); 5544 } 5545 5546 static int bpf_link_get_info_by_fd(struct file *file, 5547 struct bpf_link *link, 5548 const union bpf_attr *attr, 5549 union bpf_attr __user *uattr) 5550 { 5551 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5552 struct bpf_link_info info; 5553 const struct bpf_prog *prog; 5554 u32 info_len = attr->info.info_len; 5555 int err; 5556 5557 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5558 if (err) 5559 return err; 5560 info_len = min_t(u32, sizeof(info), info_len); 5561 5562 memset(&info, 0, sizeof(info)); 5563 if (copy_from_user(&info, uinfo, info_len)) 5564 return -EFAULT; 5565 5566 info.type = link->type; 5567 info.id = link->id; 5568 5569 rcu_read_lock(); 5570 prog = READ_ONCE(link->prog); 5571 if (prog) 5572 info.prog_id = prog->aux->id; 5573 rcu_read_unlock(); 5574 5575 if (link->ops->fill_link_info) { 5576 err = link->ops->fill_link_info(link, &info); 5577 if (err) 5578 return err; 5579 } 5580 5581 if (copy_to_user(uinfo, &info, info_len) || 5582 put_user(info_len, &uattr->info.info_len)) 5583 return -EFAULT; 5584 5585 return 0; 5586 } 5587 5588 static int token_get_info_by_fd(struct file *file, 5589 struct bpf_token *token, 5590 const union bpf_attr *attr, 5591 union bpf_attr __user *uattr) 5592 { 5593 struct bpf_token_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5594 u32 info_len = attr->info.info_len; 5595 int err; 5596 5597 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5598 if (err) 5599 return err; 5600 return bpf_token_get_info_by_fd(token, attr, uattr); 5601 } 5602 5603 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 5604 5605 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 5606 union bpf_attr __user *uattr) 5607 { 5608 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 5609 return -EINVAL; 5610 5611 CLASS(fd, f)(attr->info.bpf_fd); 5612 if (fd_empty(f)) 5613 return -EBADFD; 5614 5615 if (fd_file(f)->f_op == &bpf_prog_fops) 5616 return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5617 uattr); 5618 else if (fd_file(f)->f_op == &bpf_map_fops) 5619 return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5620 uattr); 5621 else if (fd_file(f)->f_op == &btf_fops) 5622 return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr); 5623 else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll) 5624 return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5625 attr, uattr); 5626 else if (fd_file(f)->f_op == &bpf_token_fops) 5627 return token_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5628 attr, uattr); 5629 return -EINVAL; 5630 } 5631 5632 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd 5633 5634 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_attr *attr_log) 5635 { 5636 struct bpf_token *token = NULL; 5637 5638 if (CHECK_ATTR(BPF_BTF_LOAD)) 5639 return -EINVAL; 5640 5641 if (attr->btf_flags & ~BPF_F_TOKEN_FD) 5642 return -EINVAL; 5643 5644 if (attr->btf_flags & BPF_F_TOKEN_FD) { 5645 token = bpf_token_get_from_fd(attr->btf_token_fd); 5646 if (IS_ERR(token)) 5647 return PTR_ERR(token); 5648 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { 5649 bpf_token_put(token); 5650 token = NULL; 5651 } 5652 } 5653 5654 if (!bpf_token_capable(token, CAP_BPF)) { 5655 bpf_token_put(token); 5656 return -EPERM; 5657 } 5658 5659 bpf_token_put(token); 5660 5661 return btf_new_fd(attr, uattr, attr_log); 5662 } 5663 5664 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD fd_by_id_token_fd 5665 5666 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 5667 { 5668 struct bpf_token *token = NULL; 5669 5670 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 5671 return -EINVAL; 5672 5673 if (attr->open_flags & ~BPF_F_TOKEN_FD) 5674 return -EINVAL; 5675 5676 if (attr->open_flags & BPF_F_TOKEN_FD) { 5677 token = bpf_token_get_from_fd(attr->fd_by_id_token_fd); 5678 if (IS_ERR(token)) 5679 return PTR_ERR(token); 5680 if (!bpf_token_allow_cmd(token, BPF_BTF_GET_FD_BY_ID)) { 5681 bpf_token_put(token); 5682 token = NULL; 5683 } 5684 } 5685 5686 if (!bpf_token_capable(token, CAP_SYS_ADMIN)) { 5687 bpf_token_put(token); 5688 return -EPERM; 5689 } 5690 5691 bpf_token_put(token); 5692 5693 return btf_get_fd_by_id(attr->btf_id); 5694 } 5695 5696 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 5697 union bpf_attr __user *uattr, 5698 u32 prog_id, u32 fd_type, 5699 const char *buf, u64 probe_offset, 5700 u64 probe_addr) 5701 { 5702 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 5703 u32 len = buf ? strlen(buf) : 0, input_len; 5704 int err = 0; 5705 5706 if (put_user(len, &uattr->task_fd_query.buf_len)) 5707 return -EFAULT; 5708 input_len = attr->task_fd_query.buf_len; 5709 if (input_len && ubuf) { 5710 if (!len) { 5711 /* nothing to copy, just make ubuf NULL terminated */ 5712 char zero = '\0'; 5713 5714 if (put_user(zero, ubuf)) 5715 return -EFAULT; 5716 } else { 5717 err = bpf_copy_to_user(ubuf, buf, input_len, len); 5718 if (err == -EFAULT) 5719 return err; 5720 } 5721 } 5722 5723 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 5724 put_user(fd_type, &uattr->task_fd_query.fd_type) || 5725 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 5726 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 5727 return -EFAULT; 5728 5729 return err; 5730 } 5731 5732 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 5733 5734 static int bpf_task_fd_query(const union bpf_attr *attr, 5735 union bpf_attr __user *uattr) 5736 { 5737 pid_t pid = attr->task_fd_query.pid; 5738 u32 fd = attr->task_fd_query.fd; 5739 const struct perf_event *event; 5740 struct task_struct *task; 5741 struct file *file; 5742 int err; 5743 5744 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 5745 return -EINVAL; 5746 5747 if (!capable(CAP_SYS_ADMIN)) 5748 return -EPERM; 5749 5750 if (attr->task_fd_query.flags != 0) 5751 return -EINVAL; 5752 5753 rcu_read_lock(); 5754 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 5755 rcu_read_unlock(); 5756 if (!task) 5757 return -ENOENT; 5758 5759 err = 0; 5760 file = fget_task(task, fd); 5761 put_task_struct(task); 5762 if (!file) 5763 return -EBADF; 5764 5765 if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) { 5766 struct bpf_link *link = file->private_data; 5767 5768 if (link->ops == &bpf_raw_tp_link_lops) { 5769 struct bpf_raw_tp_link *raw_tp = 5770 container_of(link, struct bpf_raw_tp_link, link); 5771 struct bpf_raw_event_map *btp = raw_tp->btp; 5772 5773 err = bpf_task_fd_query_copy(attr, uattr, 5774 raw_tp->link.prog->aux->id, 5775 BPF_FD_TYPE_RAW_TRACEPOINT, 5776 btp->tp->name, 0, 0); 5777 goto put_file; 5778 } 5779 goto out_not_supp; 5780 } 5781 5782 event = perf_get_event(file); 5783 if (!IS_ERR(event)) { 5784 u64 probe_offset, probe_addr; 5785 u32 prog_id, fd_type; 5786 const char *buf; 5787 5788 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 5789 &buf, &probe_offset, 5790 &probe_addr, NULL); 5791 if (!err) { 5792 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 5793 fd_type, buf, 5794 probe_offset, 5795 probe_addr); 5796 kfree_const(buf); 5797 } 5798 goto put_file; 5799 } 5800 5801 out_not_supp: 5802 err = -ENOTSUPP; 5803 put_file: 5804 fput(file); 5805 return err; 5806 } 5807 5808 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 5809 5810 #define BPF_DO_BATCH(fn, ...) \ 5811 do { \ 5812 if (!fn) { \ 5813 err = -ENOTSUPP; \ 5814 goto err_put; \ 5815 } \ 5816 err = fn(__VA_ARGS__); \ 5817 } while (0) 5818 5819 static int bpf_map_do_batch(const union bpf_attr *attr, 5820 union bpf_attr __user *uattr, 5821 int cmd) 5822 { 5823 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 5824 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 5825 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 5826 struct bpf_map *map; 5827 int err; 5828 5829 if (CHECK_ATTR(BPF_MAP_BATCH)) 5830 return -EINVAL; 5831 5832 CLASS(fd, f)(attr->batch.map_fd); 5833 5834 map = __bpf_map_get(f); 5835 if (IS_ERR(map)) 5836 return PTR_ERR(map); 5837 if (has_write) 5838 bpf_map_write_active_inc(map); 5839 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 5840 err = -EPERM; 5841 goto err_put; 5842 } 5843 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 5844 err = -EPERM; 5845 goto err_put; 5846 } 5847 5848 if (cmd == BPF_MAP_LOOKUP_BATCH) 5849 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); 5850 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 5851 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); 5852 else if (cmd == BPF_MAP_UPDATE_BATCH) 5853 BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr); 5854 else 5855 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); 5856 err_put: 5857 if (has_write) { 5858 maybe_wait_bpf_programs(map); 5859 bpf_map_write_active_dec(map); 5860 } 5861 return err; 5862 } 5863 5864 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.path_fd 5865 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 5866 { 5867 struct bpf_prog *prog; 5868 int ret; 5869 5870 if (CHECK_ATTR(BPF_LINK_CREATE)) 5871 return -EINVAL; 5872 5873 if (attr->link_create.attach_type == BPF_STRUCT_OPS) 5874 return bpf_struct_ops_link_create(attr); 5875 5876 prog = bpf_prog_get(attr->link_create.prog_fd); 5877 if (IS_ERR(prog)) 5878 return PTR_ERR(prog); 5879 5880 ret = bpf_prog_attach_check_attach_type(prog, 5881 attr->link_create.attach_type); 5882 if (ret) 5883 goto out; 5884 5885 switch (prog->type) { 5886 case BPF_PROG_TYPE_CGROUP_SKB: 5887 case BPF_PROG_TYPE_CGROUP_SOCK: 5888 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 5889 case BPF_PROG_TYPE_SOCK_OPS: 5890 case BPF_PROG_TYPE_CGROUP_DEVICE: 5891 case BPF_PROG_TYPE_CGROUP_SYSCTL: 5892 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 5893 ret = cgroup_bpf_link_attach(attr, prog); 5894 break; 5895 case BPF_PROG_TYPE_EXT: 5896 ret = bpf_tracing_prog_attach(prog, 5897 attr->link_create.target_fd, 5898 attr->link_create.target_btf_id, 5899 attr->link_create.tracing.cookie, 5900 attr->link_create.attach_type); 5901 break; 5902 case BPF_PROG_TYPE_LSM: 5903 case BPF_PROG_TYPE_TRACING: 5904 if (attr->link_create.attach_type != prog->expected_attach_type) { 5905 ret = -EINVAL; 5906 goto out; 5907 } 5908 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 5909 ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie, 5910 attr->link_create.attach_type); 5911 else if (prog->expected_attach_type == BPF_TRACE_ITER) 5912 ret = bpf_iter_link_attach(attr, uattr, prog); 5913 else if (prog->expected_attach_type == BPF_LSM_CGROUP) 5914 ret = cgroup_bpf_link_attach(attr, prog); 5915 else if (is_tracing_multi(prog->expected_attach_type)) 5916 ret = bpf_tracing_multi_attach(prog, attr); 5917 else 5918 ret = bpf_tracing_prog_attach(prog, 5919 attr->link_create.target_fd, 5920 attr->link_create.target_btf_id, 5921 attr->link_create.tracing.cookie, 5922 attr->link_create.attach_type); 5923 break; 5924 case BPF_PROG_TYPE_FLOW_DISSECTOR: 5925 case BPF_PROG_TYPE_SK_LOOKUP: 5926 ret = netns_bpf_link_create(attr, prog); 5927 break; 5928 case BPF_PROG_TYPE_SK_MSG: 5929 case BPF_PROG_TYPE_SK_SKB: 5930 ret = sock_map_link_create(attr, prog); 5931 break; 5932 #ifdef CONFIG_NET 5933 case BPF_PROG_TYPE_XDP: 5934 ret = bpf_xdp_link_attach(attr, prog); 5935 break; 5936 case BPF_PROG_TYPE_SCHED_CLS: 5937 if (attr->link_create.attach_type == BPF_TCX_INGRESS || 5938 attr->link_create.attach_type == BPF_TCX_EGRESS) 5939 ret = tcx_link_attach(attr, prog); 5940 else 5941 ret = netkit_link_attach(attr, prog); 5942 break; 5943 case BPF_PROG_TYPE_NETFILTER: 5944 ret = bpf_nf_link_attach(attr, prog); 5945 break; 5946 #endif 5947 case BPF_PROG_TYPE_PERF_EVENT: 5948 case BPF_PROG_TYPE_TRACEPOINT: 5949 ret = bpf_perf_link_attach(attr, prog); 5950 break; 5951 case BPF_PROG_TYPE_KPROBE: 5952 if (attr->link_create.attach_type == BPF_PERF_EVENT) 5953 ret = bpf_perf_link_attach(attr, prog); 5954 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI || 5955 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION) 5956 ret = bpf_kprobe_multi_link_attach(attr, prog); 5957 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI || 5958 attr->link_create.attach_type == BPF_TRACE_UPROBE_SESSION) 5959 ret = bpf_uprobe_multi_link_attach(attr, prog); 5960 break; 5961 default: 5962 ret = -EINVAL; 5963 } 5964 5965 out: 5966 if (ret < 0) 5967 bpf_prog_put(prog); 5968 return ret; 5969 } 5970 5971 static int link_update_map(struct bpf_link *link, union bpf_attr *attr) 5972 { 5973 struct bpf_map *new_map, *old_map = NULL; 5974 int ret; 5975 5976 new_map = bpf_map_get(attr->link_update.new_map_fd); 5977 if (IS_ERR(new_map)) 5978 return PTR_ERR(new_map); 5979 5980 if (attr->link_update.flags & BPF_F_REPLACE) { 5981 old_map = bpf_map_get(attr->link_update.old_map_fd); 5982 if (IS_ERR(old_map)) { 5983 ret = PTR_ERR(old_map); 5984 goto out_put; 5985 } 5986 } else if (attr->link_update.old_map_fd) { 5987 ret = -EINVAL; 5988 goto out_put; 5989 } 5990 5991 ret = link->ops->update_map(link, new_map, old_map); 5992 5993 if (old_map) 5994 bpf_map_put(old_map); 5995 out_put: 5996 bpf_map_put(new_map); 5997 return ret; 5998 } 5999 6000 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 6001 6002 static int link_update(union bpf_attr *attr) 6003 { 6004 struct bpf_prog *old_prog = NULL, *new_prog; 6005 struct bpf_link *link; 6006 u32 flags; 6007 int ret; 6008 6009 if (CHECK_ATTR(BPF_LINK_UPDATE)) 6010 return -EINVAL; 6011 6012 flags = attr->link_update.flags; 6013 if (flags & ~BPF_F_REPLACE) 6014 return -EINVAL; 6015 6016 link = bpf_link_get_from_fd(attr->link_update.link_fd); 6017 if (IS_ERR(link)) 6018 return PTR_ERR(link); 6019 6020 if (link->ops->update_map) { 6021 ret = link_update_map(link, attr); 6022 goto out_put_link; 6023 } 6024 6025 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 6026 if (IS_ERR(new_prog)) { 6027 ret = PTR_ERR(new_prog); 6028 goto out_put_link; 6029 } 6030 6031 if (flags & BPF_F_REPLACE) { 6032 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 6033 if (IS_ERR(old_prog)) { 6034 ret = PTR_ERR(old_prog); 6035 old_prog = NULL; 6036 goto out_put_progs; 6037 } 6038 } else if (attr->link_update.old_prog_fd) { 6039 ret = -EINVAL; 6040 goto out_put_progs; 6041 } 6042 6043 if (link->ops->update_prog) 6044 ret = link->ops->update_prog(link, new_prog, old_prog); 6045 else 6046 ret = -EINVAL; 6047 6048 out_put_progs: 6049 if (old_prog) 6050 bpf_prog_put(old_prog); 6051 if (ret) 6052 bpf_prog_put(new_prog); 6053 out_put_link: 6054 bpf_link_put_direct(link); 6055 return ret; 6056 } 6057 6058 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 6059 6060 static int link_detach(union bpf_attr *attr) 6061 { 6062 struct bpf_link *link; 6063 int ret; 6064 6065 if (CHECK_ATTR(BPF_LINK_DETACH)) 6066 return -EINVAL; 6067 6068 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 6069 if (IS_ERR(link)) 6070 return PTR_ERR(link); 6071 6072 if (link->ops->detach) 6073 ret = link->ops->detach(link); 6074 else 6075 ret = -EOPNOTSUPP; 6076 6077 bpf_link_put_direct(link); 6078 return ret; 6079 } 6080 6081 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 6082 { 6083 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 6084 } 6085 EXPORT_SYMBOL(bpf_link_inc_not_zero); 6086 6087 struct bpf_link *bpf_link_by_id(u32 id) 6088 { 6089 struct bpf_link *link; 6090 6091 if (!id) 6092 return ERR_PTR(-ENOENT); 6093 6094 spin_lock_bh(&link_idr_lock); 6095 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 6096 link = idr_find(&link_idr, id); 6097 if (link) { 6098 if (link->id) 6099 link = bpf_link_inc_not_zero(link); 6100 else 6101 link = ERR_PTR(-EAGAIN); 6102 } else { 6103 link = ERR_PTR(-ENOENT); 6104 } 6105 spin_unlock_bh(&link_idr_lock); 6106 return link; 6107 } 6108 6109 struct bpf_link *bpf_link_get_curr_or_next(u32 *id) 6110 { 6111 struct bpf_link *link; 6112 6113 spin_lock_bh(&link_idr_lock); 6114 again: 6115 link = idr_get_next(&link_idr, id); 6116 if (link) { 6117 if (link->id) 6118 link = bpf_link_inc_not_zero(link); 6119 else 6120 link = ERR_PTR(-EAGAIN); 6121 if (IS_ERR(link)) { 6122 (*id)++; 6123 goto again; 6124 } 6125 } 6126 spin_unlock_bh(&link_idr_lock); 6127 6128 return link; 6129 } 6130 6131 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 6132 6133 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 6134 { 6135 struct bpf_link *link; 6136 u32 id = attr->link_id; 6137 int fd; 6138 6139 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 6140 return -EINVAL; 6141 6142 if (!capable(CAP_SYS_ADMIN)) 6143 return -EPERM; 6144 6145 link = bpf_link_by_id(id); 6146 if (IS_ERR(link)) 6147 return PTR_ERR(link); 6148 6149 fd = bpf_link_new_fd(link); 6150 if (fd < 0) 6151 bpf_link_put_direct(link); 6152 6153 return fd; 6154 } 6155 6156 DEFINE_MUTEX(bpf_stats_enabled_mutex); 6157 6158 static int bpf_stats_release(struct inode *inode, struct file *file) 6159 { 6160 mutex_lock(&bpf_stats_enabled_mutex); 6161 static_key_slow_dec(&bpf_stats_enabled_key.key); 6162 mutex_unlock(&bpf_stats_enabled_mutex); 6163 return 0; 6164 } 6165 6166 static const struct file_operations bpf_stats_fops = { 6167 .release = bpf_stats_release, 6168 }; 6169 6170 static int bpf_enable_runtime_stats(void) 6171 { 6172 int fd; 6173 6174 mutex_lock(&bpf_stats_enabled_mutex); 6175 6176 /* Set a very high limit to avoid overflow */ 6177 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 6178 mutex_unlock(&bpf_stats_enabled_mutex); 6179 return -EBUSY; 6180 } 6181 6182 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 6183 if (fd >= 0) 6184 static_key_slow_inc(&bpf_stats_enabled_key.key); 6185 6186 mutex_unlock(&bpf_stats_enabled_mutex); 6187 return fd; 6188 } 6189 6190 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 6191 6192 static int bpf_enable_stats(union bpf_attr *attr) 6193 { 6194 6195 if (CHECK_ATTR(BPF_ENABLE_STATS)) 6196 return -EINVAL; 6197 6198 if (!capable(CAP_SYS_ADMIN)) 6199 return -EPERM; 6200 6201 switch (attr->enable_stats.type) { 6202 case BPF_STATS_RUN_TIME: 6203 return bpf_enable_runtime_stats(); 6204 default: 6205 break; 6206 } 6207 return -EINVAL; 6208 } 6209 6210 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 6211 6212 static int bpf_iter_create(union bpf_attr *attr) 6213 { 6214 struct bpf_link *link; 6215 int err; 6216 6217 if (CHECK_ATTR(BPF_ITER_CREATE)) 6218 return -EINVAL; 6219 6220 if (attr->iter_create.flags) 6221 return -EINVAL; 6222 6223 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 6224 if (IS_ERR(link)) 6225 return PTR_ERR(link); 6226 6227 err = bpf_iter_new_fd(link); 6228 bpf_link_put_direct(link); 6229 6230 return err; 6231 } 6232 6233 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 6234 6235 static int bpf_prog_bind_map(union bpf_attr *attr) 6236 { 6237 struct bpf_prog *prog; 6238 struct bpf_map *map; 6239 struct bpf_map **used_maps_old, **used_maps_new; 6240 int i, ret = 0; 6241 6242 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 6243 return -EINVAL; 6244 6245 if (attr->prog_bind_map.flags) 6246 return -EINVAL; 6247 6248 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 6249 if (IS_ERR(prog)) 6250 return PTR_ERR(prog); 6251 6252 map = bpf_map_get(attr->prog_bind_map.map_fd); 6253 if (IS_ERR(map)) { 6254 ret = PTR_ERR(map); 6255 goto out_prog_put; 6256 } 6257 6258 mutex_lock(&prog->aux->used_maps_mutex); 6259 6260 used_maps_old = prog->aux->used_maps; 6261 6262 for (i = 0; i < prog->aux->used_map_cnt; i++) 6263 if (used_maps_old[i] == map) { 6264 bpf_map_put(map); 6265 goto out_unlock; 6266 } 6267 6268 used_maps_new = kmalloc_objs(used_maps_new[0], 6269 prog->aux->used_map_cnt + 1); 6270 if (!used_maps_new) { 6271 ret = -ENOMEM; 6272 goto out_unlock; 6273 } 6274 6275 /* The bpf program will not access the bpf map, but for the sake of 6276 * simplicity, increase sleepable_refcnt for sleepable program as well. 6277 */ 6278 if (bpf_prog_runs_sleepable(prog)) 6279 atomic64_inc(&map->sleepable_refcnt); 6280 memcpy(used_maps_new, used_maps_old, 6281 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 6282 used_maps_new[prog->aux->used_map_cnt] = map; 6283 6284 prog->aux->used_map_cnt++; 6285 prog->aux->used_maps = used_maps_new; 6286 6287 kfree(used_maps_old); 6288 6289 out_unlock: 6290 mutex_unlock(&prog->aux->used_maps_mutex); 6291 6292 if (ret) 6293 bpf_map_put(map); 6294 out_prog_put: 6295 bpf_prog_put(prog); 6296 return ret; 6297 } 6298 6299 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd 6300 6301 static int token_create(union bpf_attr *attr) 6302 { 6303 if (CHECK_ATTR(BPF_TOKEN_CREATE)) 6304 return -EINVAL; 6305 6306 /* no flags are supported yet */ 6307 if (attr->token_create.flags) 6308 return -EINVAL; 6309 6310 return bpf_token_create(attr); 6311 } 6312 6313 #define BPF_PROG_STREAM_READ_BY_FD_LAST_FIELD prog_stream_read.prog_fd 6314 6315 static int prog_stream_read(union bpf_attr *attr) 6316 { 6317 char __user *buf = u64_to_user_ptr(attr->prog_stream_read.stream_buf); 6318 u32 len = attr->prog_stream_read.stream_buf_len; 6319 struct bpf_prog *prog; 6320 int ret; 6321 6322 if (CHECK_ATTR(BPF_PROG_STREAM_READ_BY_FD)) 6323 return -EINVAL; 6324 6325 prog = bpf_prog_get(attr->prog_stream_read.prog_fd); 6326 if (IS_ERR(prog)) 6327 return PTR_ERR(prog); 6328 6329 ret = bpf_prog_stream_read(prog, attr->prog_stream_read.stream_id, buf, len); 6330 bpf_prog_put(prog); 6331 6332 return ret; 6333 } 6334 6335 #define BPF_PROG_ASSOC_STRUCT_OPS_LAST_FIELD prog_assoc_struct_ops.flags 6336 6337 static int prog_assoc_struct_ops(union bpf_attr *attr) 6338 { 6339 struct bpf_prog *prog; 6340 struct bpf_map *map; 6341 int ret; 6342 6343 if (CHECK_ATTR(BPF_PROG_ASSOC_STRUCT_OPS)) 6344 return -EINVAL; 6345 6346 if (attr->prog_assoc_struct_ops.flags) 6347 return -EINVAL; 6348 6349 prog = bpf_prog_get(attr->prog_assoc_struct_ops.prog_fd); 6350 if (IS_ERR(prog)) 6351 return PTR_ERR(prog); 6352 6353 if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) { 6354 ret = -EINVAL; 6355 goto put_prog; 6356 } 6357 6358 map = bpf_map_get(attr->prog_assoc_struct_ops.map_fd); 6359 if (IS_ERR(map)) { 6360 ret = PTR_ERR(map); 6361 goto put_prog; 6362 } 6363 6364 if (map->map_type != BPF_MAP_TYPE_STRUCT_OPS) { 6365 ret = -EINVAL; 6366 goto put_map; 6367 } 6368 6369 ret = bpf_prog_assoc_struct_ops(prog, map); 6370 6371 put_map: 6372 bpf_map_put(map); 6373 put_prog: 6374 bpf_prog_put(prog); 6375 return ret; 6376 } 6377 6378 #define BPF_PROG_STREAM_OPEN_LAST_FIELD prog_stream_open.flags 6379 6380 static int prog_stream_open(union bpf_attr *attr) 6381 { 6382 struct bpf_prog *prog; 6383 u32 flags = attr->prog_stream_open.flags; 6384 int ret; 6385 6386 if (CHECK_ATTR(BPF_PROG_STREAM_OPEN)) 6387 return -EINVAL; 6388 if (flags & ~BPF_F_STREAM_NONBLOCK) 6389 return -EINVAL; 6390 6391 prog = bpf_prog_get(attr->prog_stream_open.prog_fd); 6392 if (IS_ERR(prog)) 6393 return PTR_ERR(prog); 6394 6395 ret = bpf_prog_stream_new_fd(prog, attr->prog_stream_open.stream_id, flags); 6396 bpf_prog_put(prog); 6397 return ret; 6398 } 6399 6400 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size, 6401 bpfptr_t uattr_common, unsigned int size_common) 6402 { 6403 struct bpf_common_attr attr_common; 6404 u32 offsetof_log_true_size = 0; 6405 struct bpf_log_attr attr_log; 6406 union bpf_attr attr; 6407 int err; 6408 6409 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 6410 if (err) 6411 return err; 6412 size = min_t(u32, size, sizeof(attr)); 6413 6414 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 6415 memset(&attr, 0, sizeof(attr)); 6416 if (copy_from_bpfptr(&attr, uattr, size) != 0) 6417 return -EFAULT; 6418 6419 memset(&attr_common, 0, sizeof(attr_common)); 6420 if (cmd & BPF_COMMON_ATTRS) { 6421 err = bpf_check_uarg_tail_zero(uattr_common, 6422 offsetofend(struct bpf_common_attr, log_true_size), 6423 size_common); 6424 if (err) 6425 return err; 6426 6427 cmd &= ~BPF_COMMON_ATTRS; 6428 size_common = min_t(u32, size_common, sizeof(attr_common)); 6429 if (copy_from_bpfptr(&attr_common, uattr_common, size_common) != 0) 6430 return -EFAULT; 6431 } else { 6432 size_common = 0; 6433 } 6434 6435 err = security_bpf(cmd, &attr, size, uattr.is_kernel); 6436 if (err < 0) 6437 return err; 6438 6439 switch (cmd) { 6440 case BPF_MAP_CREATE: 6441 err = map_create(&attr, uattr, &attr_common, uattr_common, size_common); 6442 break; 6443 case BPF_MAP_LOOKUP_ELEM: 6444 err = map_lookup_elem(&attr); 6445 break; 6446 case BPF_MAP_UPDATE_ELEM: 6447 err = map_update_elem(&attr, uattr); 6448 break; 6449 case BPF_MAP_DELETE_ELEM: 6450 err = map_delete_elem(&attr, uattr); 6451 break; 6452 case BPF_MAP_GET_NEXT_KEY: 6453 err = map_get_next_key(&attr); 6454 break; 6455 case BPF_MAP_FREEZE: 6456 err = map_freeze(&attr); 6457 break; 6458 case BPF_PROG_LOAD: 6459 if (size >= offsetofend(union bpf_attr, log_true_size)) 6460 offsetof_log_true_size = offsetof(union bpf_attr, log_true_size); 6461 err = bpf_log_attr_init(&attr_log, attr.log_buf, attr.log_size, attr.log_level, 6462 offsetof_log_true_size, uattr, &attr_common, uattr_common, 6463 size_common); 6464 err = err ?: bpf_prog_load(&attr, uattr, &attr_log); 6465 break; 6466 case BPF_OBJ_PIN: 6467 err = bpf_obj_pin(&attr); 6468 break; 6469 case BPF_OBJ_GET: 6470 err = bpf_obj_get(&attr); 6471 break; 6472 case BPF_PROG_ATTACH: 6473 err = bpf_prog_attach(&attr); 6474 break; 6475 case BPF_PROG_DETACH: 6476 err = bpf_prog_detach(&attr); 6477 break; 6478 case BPF_PROG_QUERY: 6479 err = bpf_prog_query(&attr, uattr.user, size); 6480 break; 6481 case BPF_PROG_TEST_RUN: 6482 err = bpf_prog_test_run(&attr, uattr.user); 6483 break; 6484 case BPF_PROG_GET_NEXT_ID: 6485 err = bpf_obj_get_next_id(&attr, uattr.user, 6486 &prog_idr, &prog_idr_lock); 6487 break; 6488 case BPF_MAP_GET_NEXT_ID: 6489 err = bpf_obj_get_next_id(&attr, uattr.user, 6490 &map_idr, &map_idr_lock); 6491 break; 6492 case BPF_BTF_GET_NEXT_ID: 6493 err = bpf_obj_get_next_id(&attr, uattr.user, 6494 &btf_idr, &btf_idr_lock); 6495 break; 6496 case BPF_PROG_GET_FD_BY_ID: 6497 err = bpf_prog_get_fd_by_id(&attr); 6498 break; 6499 case BPF_MAP_GET_FD_BY_ID: 6500 err = bpf_map_get_fd_by_id(&attr); 6501 break; 6502 case BPF_OBJ_GET_INFO_BY_FD: 6503 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 6504 break; 6505 case BPF_RAW_TRACEPOINT_OPEN: 6506 err = bpf_raw_tracepoint_open(&attr); 6507 break; 6508 case BPF_BTF_LOAD: 6509 if (size >= offsetofend(union bpf_attr, btf_log_true_size)) 6510 offsetof_log_true_size = offsetof(union bpf_attr, btf_log_true_size); 6511 err = bpf_log_attr_init(&attr_log, attr.btf_log_buf, attr.btf_log_size, 6512 attr.btf_log_level, offsetof_log_true_size, uattr, 6513 &attr_common, uattr_common, size_common); 6514 err = err ?: bpf_btf_load(&attr, uattr, &attr_log); 6515 break; 6516 case BPF_BTF_GET_FD_BY_ID: 6517 err = bpf_btf_get_fd_by_id(&attr); 6518 break; 6519 case BPF_TASK_FD_QUERY: 6520 err = bpf_task_fd_query(&attr, uattr.user); 6521 break; 6522 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 6523 err = map_lookup_and_delete_elem(&attr); 6524 break; 6525 case BPF_MAP_LOOKUP_BATCH: 6526 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 6527 break; 6528 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 6529 err = bpf_map_do_batch(&attr, uattr.user, 6530 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 6531 break; 6532 case BPF_MAP_UPDATE_BATCH: 6533 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 6534 break; 6535 case BPF_MAP_DELETE_BATCH: 6536 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 6537 break; 6538 case BPF_LINK_CREATE: 6539 err = link_create(&attr, uattr); 6540 break; 6541 case BPF_LINK_UPDATE: 6542 err = link_update(&attr); 6543 break; 6544 case BPF_LINK_GET_FD_BY_ID: 6545 err = bpf_link_get_fd_by_id(&attr); 6546 break; 6547 case BPF_LINK_GET_NEXT_ID: 6548 err = bpf_obj_get_next_id(&attr, uattr.user, 6549 &link_idr, &link_idr_lock); 6550 break; 6551 case BPF_ENABLE_STATS: 6552 err = bpf_enable_stats(&attr); 6553 break; 6554 case BPF_ITER_CREATE: 6555 err = bpf_iter_create(&attr); 6556 break; 6557 case BPF_LINK_DETACH: 6558 err = link_detach(&attr); 6559 break; 6560 case BPF_PROG_BIND_MAP: 6561 err = bpf_prog_bind_map(&attr); 6562 break; 6563 case BPF_TOKEN_CREATE: 6564 err = token_create(&attr); 6565 break; 6566 case BPF_PROG_STREAM_READ_BY_FD: 6567 err = prog_stream_read(&attr); 6568 break; 6569 case BPF_PROG_ASSOC_STRUCT_OPS: 6570 err = prog_assoc_struct_ops(&attr); 6571 break; 6572 case BPF_PROG_STREAM_OPEN: 6573 err = prog_stream_open(&attr); 6574 break; 6575 default: 6576 err = -EINVAL; 6577 break; 6578 } 6579 6580 return err; 6581 } 6582 6583 SYSCALL_DEFINE5(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size, 6584 struct bpf_common_attr __user *, uattr_common, unsigned int, size_common) 6585 { 6586 return __sys_bpf(cmd, USER_BPFPTR(uattr), size, USER_BPFPTR(uattr_common), size_common); 6587 } 6588 6589 static bool syscall_prog_is_valid_access(int off, int size, 6590 enum bpf_access_type type, 6591 const struct bpf_prog *prog, 6592 struct bpf_insn_access_aux *info) 6593 { 6594 if (off < 0 || off >= U16_MAX) 6595 return false; 6596 /* No alignment requirements for syscall ctx accesses. */ 6597 return true; 6598 } 6599 6600 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 6601 { 6602 switch (cmd) { 6603 case BPF_MAP_CREATE: 6604 case BPF_MAP_DELETE_ELEM: 6605 case BPF_MAP_UPDATE_ELEM: 6606 case BPF_MAP_FREEZE: 6607 case BPF_MAP_GET_FD_BY_ID: 6608 case BPF_PROG_LOAD: 6609 case BPF_BTF_LOAD: 6610 case BPF_LINK_CREATE: 6611 case BPF_RAW_TRACEPOINT_OPEN: 6612 break; 6613 default: 6614 return -EINVAL; 6615 } 6616 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size, KERNEL_BPFPTR(NULL), 0); 6617 } 6618 6619 /* To shut up -Wmissing-prototypes. 6620 * This function is used by the kernel light skeleton 6621 * to load bpf programs when modules are loaded or during kernel boot. 6622 * See tools/lib/bpf/skel_internal.h 6623 */ 6624 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); 6625 6626 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) 6627 { 6628 struct bpf_prog * __maybe_unused prog; 6629 struct bpf_tramp_run_ctx __maybe_unused run_ctx; 6630 6631 switch (cmd) { 6632 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 6633 case BPF_PROG_TEST_RUN: 6634 if (attr->test.data_in || attr->test.data_out || 6635 attr->test.ctx_out || attr->test.duration || 6636 attr->test.repeat || attr->test.flags) 6637 return -EINVAL; 6638 6639 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 6640 if (IS_ERR(prog)) 6641 return PTR_ERR(prog); 6642 6643 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 6644 attr->test.ctx_size_in > U16_MAX) { 6645 bpf_prog_put(prog); 6646 return -EINVAL; 6647 } 6648 6649 run_ctx.bpf_cookie = 0; 6650 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { 6651 /* recursion detected */ 6652 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); 6653 bpf_prog_put(prog); 6654 return -EBUSY; 6655 } 6656 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 6657 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, 6658 &run_ctx); 6659 bpf_prog_put(prog); 6660 return 0; 6661 #endif 6662 default: 6663 return ____bpf_sys_bpf(cmd, attr, size); 6664 } 6665 } 6666 EXPORT_SYMBOL_NS(kern_sys_bpf, "BPF_INTERNAL"); 6667 6668 static const struct bpf_func_proto bpf_sys_bpf_proto = { 6669 .func = bpf_sys_bpf, 6670 .gpl_only = false, 6671 .might_sleep = true, 6672 .ret_type = RET_INTEGER, 6673 .arg1_type = ARG_ANYTHING, 6674 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 6675 .arg3_type = ARG_MEM_SIZE, 6676 }; 6677 6678 const struct bpf_func_proto * __weak 6679 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6680 { 6681 return bpf_base_func_proto(func_id, prog); 6682 } 6683 6684 BPF_CALL_1(bpf_sys_close, u32, fd) 6685 { 6686 /* When bpf program calls this helper there should not be 6687 * an fdget() without matching completed fdput(). 6688 * This helper is allowed in the following callchain only: 6689 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 6690 */ 6691 return close_fd(fd); 6692 } 6693 6694 static const struct bpf_func_proto bpf_sys_close_proto = { 6695 .func = bpf_sys_close, 6696 .gpl_only = false, 6697 .might_sleep = true, 6698 .ret_type = RET_INTEGER, 6699 .arg1_type = ARG_ANYTHING, 6700 }; 6701 6702 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 6703 { 6704 *res = 0; 6705 if (flags) 6706 return -EINVAL; 6707 6708 if (name_sz <= 1 || name[name_sz - 1]) 6709 return -EINVAL; 6710 6711 if (!bpf_dump_raw_ok(current_cred())) 6712 return -EPERM; 6713 6714 *res = kallsyms_lookup_name(name); 6715 return *res ? 0 : -ENOENT; 6716 } 6717 6718 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 6719 .func = bpf_kallsyms_lookup_name, 6720 .gpl_only = false, 6721 .ret_type = RET_INTEGER, 6722 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY, 6723 .arg2_type = ARG_MEM_SIZE_OR_ZERO, 6724 .arg3_type = ARG_ANYTHING, 6725 .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_WRITE | MEM_ALIGNED, 6726 .arg4_size = sizeof(u64), 6727 }; 6728 6729 static const struct bpf_func_proto * 6730 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6731 { 6732 switch (func_id) { 6733 case BPF_FUNC_sys_bpf: 6734 return !bpf_token_capable(prog->aux->token, CAP_PERFMON) 6735 ? NULL : &bpf_sys_bpf_proto; 6736 case BPF_FUNC_btf_find_by_name_kind: 6737 return &bpf_btf_find_by_name_kind_proto; 6738 case BPF_FUNC_sys_close: 6739 return &bpf_sys_close_proto; 6740 case BPF_FUNC_kallsyms_lookup_name: 6741 return &bpf_kallsyms_lookup_name_proto; 6742 default: 6743 return tracing_prog_func_proto(func_id, prog); 6744 } 6745 } 6746 6747 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 6748 .get_func_proto = syscall_prog_func_proto, 6749 .is_valid_access = syscall_prog_is_valid_access, 6750 }; 6751 6752 const struct bpf_prog_ops bpf_syscall_prog_ops = { 6753 .test_run = bpf_prog_test_run_syscall, 6754 }; 6755 6756 #ifdef CONFIG_SYSCTL 6757 static int bpf_stats_handler(const struct ctl_table *table, int write, 6758 void *buffer, size_t *lenp, loff_t *ppos) 6759 { 6760 struct static_key *key = (struct static_key *)table->data; 6761 static int saved_val; 6762 int val, ret; 6763 struct ctl_table tmp = { 6764 .data = &val, 6765 .maxlen = sizeof(val), 6766 .mode = table->mode, 6767 .extra1 = SYSCTL_ZERO, 6768 .extra2 = SYSCTL_ONE, 6769 }; 6770 6771 if (write && !capable(CAP_SYS_ADMIN)) 6772 return -EPERM; 6773 6774 mutex_lock(&bpf_stats_enabled_mutex); 6775 val = saved_val; 6776 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6777 if (write && !ret && val != saved_val) { 6778 if (val) 6779 static_key_slow_inc(key); 6780 else 6781 static_key_slow_dec(key); 6782 saved_val = val; 6783 } 6784 mutex_unlock(&bpf_stats_enabled_mutex); 6785 return ret; 6786 } 6787 6788 void __weak unpriv_ebpf_notify(int new_state) 6789 { 6790 } 6791 6792 static int bpf_unpriv_handler(const struct ctl_table *table, int write, 6793 void *buffer, size_t *lenp, loff_t *ppos) 6794 { 6795 int ret, unpriv_enable = *(int *)table->data; 6796 bool locked_state = unpriv_enable == 1; 6797 struct ctl_table tmp = *table; 6798 6799 if (write && !capable(CAP_SYS_ADMIN)) 6800 return -EPERM; 6801 6802 tmp.data = &unpriv_enable; 6803 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6804 if (write && !ret) { 6805 if (locked_state && unpriv_enable != 1) 6806 return -EPERM; 6807 *(int *)table->data = unpriv_enable; 6808 } 6809 6810 if (write) 6811 unpriv_ebpf_notify(unpriv_enable); 6812 6813 return ret; 6814 } 6815 6816 static const struct ctl_table bpf_syscall_table[] = { 6817 { 6818 .procname = "unprivileged_bpf_disabled", 6819 .data = &sysctl_unprivileged_bpf_disabled, 6820 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), 6821 .mode = 0644, 6822 .proc_handler = bpf_unpriv_handler, 6823 .extra1 = SYSCTL_ZERO, 6824 .extra2 = SYSCTL_TWO, 6825 }, 6826 { 6827 .procname = "bpf_stats_enabled", 6828 .data = &bpf_stats_enabled_key.key, 6829 .mode = 0644, 6830 .proc_handler = bpf_stats_handler, 6831 }, 6832 }; 6833 6834 static int __init bpf_syscall_sysctl_init(void) 6835 { 6836 register_sysctl_init("kernel", bpf_syscall_table); 6837 return 0; 6838 } 6839 late_initcall(bpf_syscall_sysctl_init); 6840 #endif /* CONFIG_SYSCTL */ 6841