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/verification.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 static struct page *__bpf_alloc_page(int nid) 606 { 607 if (!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, 613 0); 614 } 615 616 int bpf_map_alloc_pages(const struct bpf_map *map, int nid, 617 unsigned long nr_pages, struct page **pages) 618 { 619 unsigned long i, j; 620 struct page *pg; 621 int ret = 0; 622 623 for (i = 0; i < nr_pages; i++) { 624 pg = __bpf_alloc_page(nid); 625 626 if (pg) { 627 pages[i] = pg; 628 continue; 629 } 630 for (j = 0; j < i; j++) 631 free_pages_nolock(pages[j], 0); 632 ret = -ENOMEM; 633 break; 634 } 635 636 return ret; 637 } 638 639 640 static int btf_field_cmp(const void *a, const void *b) 641 { 642 const struct btf_field *f1 = a, *f2 = b; 643 644 if (f1->offset < f2->offset) 645 return -1; 646 else if (f1->offset > f2->offset) 647 return 1; 648 return 0; 649 } 650 651 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, 652 u32 field_mask) 653 { 654 struct btf_field *field; 655 656 if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask)) 657 return NULL; 658 field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); 659 if (!field || !(field->type & field_mask)) 660 return NULL; 661 return field; 662 } 663 664 void btf_record_free(struct btf_record *rec) 665 { 666 int i; 667 668 if (IS_ERR_OR_NULL(rec)) 669 return; 670 for (i = 0; i < rec->cnt; i++) { 671 switch (rec->fields[i].type) { 672 case BPF_KPTR_UNREF: 673 case BPF_KPTR_REF: 674 case BPF_KPTR_PERCPU: 675 case BPF_UPTR: 676 if (rec->fields[i].kptr.module) 677 module_put(rec->fields[i].kptr.module); 678 if (btf_is_kernel(rec->fields[i].kptr.btf)) 679 btf_put(rec->fields[i].kptr.btf); 680 break; 681 case BPF_LIST_HEAD: 682 case BPF_LIST_NODE: 683 case BPF_RB_ROOT: 684 case BPF_RB_NODE: 685 case BPF_SPIN_LOCK: 686 case BPF_RES_SPIN_LOCK: 687 case BPF_TIMER: 688 case BPF_REFCOUNT: 689 case BPF_WORKQUEUE: 690 case BPF_TASK_WORK: 691 /* Nothing to release */ 692 break; 693 default: 694 WARN_ON_ONCE(1); 695 continue; 696 } 697 } 698 kfree(rec); 699 } 700 701 void bpf_map_free_record(struct bpf_map *map) 702 { 703 btf_record_free(map->record); 704 map->record = NULL; 705 } 706 707 struct btf_record *btf_record_dup(const struct btf_record *rec) 708 { 709 const struct btf_field *fields; 710 struct btf_record *new_rec; 711 int ret, size, i; 712 713 if (IS_ERR_OR_NULL(rec)) 714 return NULL; 715 size = struct_size(rec, fields, rec->cnt); 716 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); 717 if (!new_rec) 718 return ERR_PTR(-ENOMEM); 719 /* Do a deep copy of the btf_record */ 720 fields = rec->fields; 721 new_rec->cnt = 0; 722 for (i = 0; i < rec->cnt; i++) { 723 switch (fields[i].type) { 724 case BPF_KPTR_UNREF: 725 case BPF_KPTR_REF: 726 case BPF_KPTR_PERCPU: 727 case BPF_UPTR: 728 if (btf_is_kernel(fields[i].kptr.btf)) 729 btf_get(fields[i].kptr.btf); 730 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { 731 ret = -ENXIO; 732 goto free; 733 } 734 break; 735 case BPF_LIST_HEAD: 736 case BPF_LIST_NODE: 737 case BPF_RB_ROOT: 738 case BPF_RB_NODE: 739 case BPF_SPIN_LOCK: 740 case BPF_RES_SPIN_LOCK: 741 case BPF_TIMER: 742 case BPF_REFCOUNT: 743 case BPF_WORKQUEUE: 744 case BPF_TASK_WORK: 745 /* Nothing to acquire */ 746 break; 747 default: 748 ret = -EFAULT; 749 WARN_ON_ONCE(1); 750 goto free; 751 } 752 new_rec->cnt++; 753 } 754 return new_rec; 755 free: 756 btf_record_free(new_rec); 757 return ERR_PTR(ret); 758 } 759 760 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) 761 { 762 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); 763 int size; 764 765 if (!a_has_fields && !b_has_fields) 766 return true; 767 if (a_has_fields != b_has_fields) 768 return false; 769 if (rec_a->cnt != rec_b->cnt) 770 return false; 771 size = struct_size(rec_a, fields, rec_a->cnt); 772 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused 773 * members are zeroed out. So memcmp is safe to do without worrying 774 * about padding/unused fields. 775 * 776 * While spin_lock, timer, and kptr have no relation to map BTF, 777 * list_head metadata is specific to map BTF, the btf and value_rec 778 * members in particular. btf is the map BTF, while value_rec points to 779 * btf_record in that map BTF. 780 * 781 * So while by default, we don't rely on the map BTF (which the records 782 * were parsed from) matching for both records, which is not backwards 783 * compatible, in case list_head is part of it, we implicitly rely on 784 * that by way of depending on memcmp succeeding for it. 785 */ 786 return !memcmp(rec_a, rec_b, size); 787 } 788 789 void bpf_obj_free_timer(const struct btf_record *rec, void *obj) 790 { 791 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) 792 return; 793 bpf_timer_cancel_and_free(obj + rec->timer_off); 794 } 795 796 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj) 797 { 798 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE))) 799 return; 800 bpf_wq_cancel_and_free(obj + rec->wq_off); 801 } 802 803 void bpf_obj_free_task_work(const struct btf_record *rec, void *obj) 804 { 805 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TASK_WORK))) 806 return; 807 bpf_task_work_cancel_and_free(obj + rec->task_work_off); 808 } 809 810 void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 811 { 812 const struct btf_field *fields; 813 int i; 814 815 if (IS_ERR_OR_NULL(rec)) 816 return; 817 fields = rec->fields; 818 for (i = 0; i < rec->cnt; i++) { 819 struct btf_struct_meta *pointee_struct_meta; 820 const struct btf_field *field = &fields[i]; 821 void *field_ptr = obj + field->offset; 822 void *xchgd_field; 823 824 switch (fields[i].type) { 825 case BPF_SPIN_LOCK: 826 case BPF_RES_SPIN_LOCK: 827 break; 828 case BPF_TIMER: 829 bpf_timer_cancel_and_free(field_ptr); 830 break; 831 case BPF_WORKQUEUE: 832 bpf_wq_cancel_and_free(field_ptr); 833 break; 834 case BPF_TASK_WORK: 835 bpf_task_work_cancel_and_free(field_ptr); 836 break; 837 case BPF_KPTR_UNREF: 838 WRITE_ONCE(*(u64 *)field_ptr, 0); 839 break; 840 case BPF_KPTR_REF: 841 case BPF_KPTR_PERCPU: 842 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); 843 if (!xchgd_field) 844 break; 845 846 if (!btf_is_kernel(field->kptr.btf)) { 847 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, 848 field->kptr.btf_id); 849 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? 850 pointee_struct_meta->record : NULL, 851 fields[i].type == BPF_KPTR_PERCPU); 852 } else { 853 field->kptr.dtor(xchgd_field); 854 } 855 break; 856 case BPF_UPTR: 857 /* The caller ensured that no one is using the uptr */ 858 unpin_uptr_kaddr(*(void **)field_ptr); 859 break; 860 case BPF_LIST_HEAD: 861 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 862 continue; 863 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); 864 break; 865 case BPF_RB_ROOT: 866 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 867 continue; 868 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); 869 break; 870 case BPF_LIST_NODE: 871 case BPF_RB_NODE: 872 case BPF_REFCOUNT: 873 break; 874 default: 875 WARN_ON_ONCE(1); 876 continue; 877 } 878 } 879 } 880 881 static void bpf_map_free(struct bpf_map *map) 882 { 883 struct btf_record *rec = map->record; 884 struct btf *btf = map->btf; 885 886 /* implementation dependent freeing. Disabling migration to simplify 887 * the free of values or special fields allocated from bpf memory 888 * allocator. 889 */ 890 kfree(map->excl_prog_sha); 891 migrate_disable(); 892 map->ops->map_free(map); 893 migrate_enable(); 894 895 /* Delay freeing of btf_record for maps, as map_free 896 * callback usually needs access to them. It is better to do it here 897 * than require each callback to do the free itself manually. 898 * 899 * Note that the btf_record stashed in map->inner_map_meta->record was 900 * already freed using the map_free callback for map in map case which 901 * eventually calls bpf_map_free_meta, since inner_map_meta is only a 902 * template bpf_map struct used during verification. 903 */ 904 btf_record_free(rec); 905 /* Delay freeing of btf for maps, as map_free callback may need 906 * struct_meta info which will be freed with btf_put(). 907 */ 908 btf_put(btf); 909 } 910 911 /* called from workqueue */ 912 static void bpf_map_free_deferred(struct work_struct *work) 913 { 914 struct bpf_map *map = container_of(work, struct bpf_map, work); 915 916 security_bpf_map_free(map); 917 bpf_map_release_memcg(map); 918 bpf_map_owner_free(map); 919 bpf_map_free(map); 920 } 921 922 static void bpf_map_put_uref(struct bpf_map *map) 923 { 924 if (atomic64_dec_and_test(&map->usercnt)) { 925 if (map->ops->map_release_uref) 926 map->ops->map_release_uref(map); 927 } 928 } 929 930 static void bpf_map_free_in_work(struct bpf_map *map) 931 { 932 INIT_WORK(&map->work, bpf_map_free_deferred); 933 /* Avoid spawning kworkers, since they all might contend 934 * for the same mutex like slab_mutex. 935 */ 936 queue_work(system_dfl_wq, &map->work); 937 } 938 939 static void bpf_map_free_rcu_gp(struct rcu_head *rcu) 940 { 941 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); 942 } 943 944 /* decrement map refcnt and schedule it for freeing via workqueue 945 * (underlying map implementation ops->map_free() might sleep) 946 */ 947 void bpf_map_put(struct bpf_map *map) 948 { 949 if (atomic64_dec_and_test(&map->refcnt)) { 950 /* bpf_map_free_id() must be called first */ 951 bpf_map_free_id(map); 952 953 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); 954 /* RCU tasks trace grace period implies RCU grace period. */ 955 if (READ_ONCE(map->free_after_mult_rcu_gp)) 956 call_rcu_tasks_trace(&map->rcu, bpf_map_free_rcu_gp); 957 else if (READ_ONCE(map->free_after_rcu_gp)) 958 call_rcu(&map->rcu, bpf_map_free_rcu_gp); 959 else 960 bpf_map_free_in_work(map); 961 } 962 } 963 EXPORT_SYMBOL_GPL(bpf_map_put); 964 965 void bpf_map_put_with_uref(struct bpf_map *map) 966 { 967 bpf_map_put_uref(map); 968 bpf_map_put(map); 969 } 970 971 static int bpf_map_release(struct inode *inode, struct file *filp) 972 { 973 struct bpf_map *map = filp->private_data; 974 975 if (map->ops->map_release) 976 map->ops->map_release(map, filp); 977 978 bpf_map_put_with_uref(map); 979 return 0; 980 } 981 982 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 983 { 984 fmode_t mode = fd_file(f)->f_mode; 985 986 /* Our file permissions may have been overridden by global 987 * map permissions facing syscall side. 988 */ 989 if (READ_ONCE(map->frozen)) 990 mode &= ~FMODE_CAN_WRITE; 991 return mode; 992 } 993 994 #ifdef CONFIG_PROC_FS 995 /* Show the memory usage of a bpf map */ 996 static u64 bpf_map_memory_usage(const struct bpf_map *map) 997 { 998 return map->ops->map_mem_usage(map); 999 } 1000 1001 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 1002 { 1003 struct bpf_map *map = filp->private_data; 1004 u32 type = 0, jited = 0; 1005 1006 spin_lock(&map->owner_lock); 1007 if (map->owner) { 1008 type = map->owner->type; 1009 jited = map->owner->jited; 1010 } 1011 spin_unlock(&map->owner_lock); 1012 1013 seq_printf(m, 1014 "map_type:\t%u\n" 1015 "key_size:\t%u\n" 1016 "value_size:\t%u\n" 1017 "max_entries:\t%u\n" 1018 "map_flags:\t%#x\n" 1019 "map_extra:\t%#llx\n" 1020 "memlock:\t%llu\n" 1021 "map_id:\t%u\n" 1022 "frozen:\t%u\n", 1023 map->map_type, 1024 map->key_size, 1025 map->value_size, 1026 map->max_entries, 1027 map->map_flags, 1028 (unsigned long long)map->map_extra, 1029 bpf_map_memory_usage(map), 1030 map->id, 1031 READ_ONCE(map->frozen)); 1032 if (type) { 1033 seq_printf(m, "owner_prog_type:\t%u\n", type); 1034 seq_printf(m, "owner_jited:\t%u\n", jited); 1035 } 1036 } 1037 #endif 1038 1039 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 1040 loff_t *ppos) 1041 { 1042 /* We need this handler such that alloc_file() enables 1043 * f_mode with FMODE_CAN_READ. 1044 */ 1045 return -EINVAL; 1046 } 1047 1048 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 1049 size_t siz, loff_t *ppos) 1050 { 1051 /* We need this handler such that alloc_file() enables 1052 * f_mode with FMODE_CAN_WRITE. 1053 */ 1054 return -EINVAL; 1055 } 1056 1057 /* called for any extra memory-mapped regions (except initial) */ 1058 static void bpf_map_mmap_open(struct vm_area_struct *vma) 1059 { 1060 struct bpf_map *map = vma->vm_file->private_data; 1061 1062 if (vma->vm_flags & VM_MAYWRITE) 1063 bpf_map_write_active_inc(map); 1064 } 1065 1066 /* called for all unmapped memory region (including initial) */ 1067 static void bpf_map_mmap_close(struct vm_area_struct *vma) 1068 { 1069 struct bpf_map *map = vma->vm_file->private_data; 1070 1071 if (vma->vm_flags & VM_MAYWRITE) 1072 bpf_map_write_active_dec(map); 1073 } 1074 1075 static const struct vm_operations_struct bpf_map_default_vmops = { 1076 .open = bpf_map_mmap_open, 1077 .close = bpf_map_mmap_close, 1078 }; 1079 1080 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 1081 { 1082 struct bpf_map *map = filp->private_data; 1083 int err = 0; 1084 1085 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) 1086 return -ENOTSUPP; 1087 1088 if (!(vma->vm_flags & VM_SHARED)) 1089 return -EINVAL; 1090 1091 mutex_lock(&map->freeze_mutex); 1092 1093 if (vma->vm_flags & VM_WRITE) { 1094 if (map->frozen) { 1095 err = -EPERM; 1096 goto out; 1097 } 1098 /* map is meant to be read-only, so do not allow mapping as 1099 * writable, because it's possible to leak a writable page 1100 * reference and allows user-space to still modify it after 1101 * freezing, while verifier will assume contents do not change 1102 */ 1103 if (map->map_flags & BPF_F_RDONLY_PROG) { 1104 err = -EACCES; 1105 goto out; 1106 } 1107 bpf_map_write_active_inc(map); 1108 } 1109 out: 1110 mutex_unlock(&map->freeze_mutex); 1111 if (err) 1112 return err; 1113 1114 /* set default open/close callbacks */ 1115 vma->vm_ops = &bpf_map_default_vmops; 1116 vma->vm_private_data = map; 1117 vm_flags_clear(vma, VM_MAYEXEC); 1118 /* If mapping is read-only, then disallow potentially re-mapping with 1119 * PROT_WRITE by dropping VM_MAYWRITE flag. This VM_MAYWRITE clearing 1120 * means that as far as BPF map's memory-mapped VMAs are concerned, 1121 * VM_WRITE and VM_MAYWRITE and equivalent, if one of them is set, 1122 * both should be set, so we can forget about VM_MAYWRITE and always 1123 * check just VM_WRITE 1124 */ 1125 if (!(vma->vm_flags & VM_WRITE)) 1126 vm_flags_clear(vma, VM_MAYWRITE); 1127 1128 err = map->ops->map_mmap(map, vma); 1129 if (err) { 1130 if (vma->vm_flags & VM_WRITE) 1131 bpf_map_write_active_dec(map); 1132 } 1133 1134 return err; 1135 } 1136 1137 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 1138 { 1139 struct bpf_map *map = filp->private_data; 1140 1141 if (map->ops->map_poll) 1142 return map->ops->map_poll(map, filp, pts); 1143 1144 return EPOLLERR; 1145 } 1146 1147 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, 1148 unsigned long len, unsigned long pgoff, 1149 unsigned long flags) 1150 { 1151 struct bpf_map *map = filp->private_data; 1152 1153 if (map->ops->map_get_unmapped_area) 1154 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); 1155 #ifdef CONFIG_MMU 1156 return mm_get_unmapped_area(filp, addr, len, pgoff, flags); 1157 #else 1158 return addr; 1159 #endif 1160 } 1161 1162 const struct file_operations bpf_map_fops = { 1163 #ifdef CONFIG_PROC_FS 1164 .show_fdinfo = bpf_map_show_fdinfo, 1165 #endif 1166 .release = bpf_map_release, 1167 .read = bpf_dummy_read, 1168 .write = bpf_dummy_write, 1169 .mmap = bpf_map_mmap, 1170 .poll = bpf_map_poll, 1171 .get_unmapped_area = bpf_get_unmapped_area, 1172 }; 1173 1174 int bpf_map_new_fd(struct bpf_map *map, int flags) 1175 { 1176 int ret; 1177 1178 ret = security_bpf_map(map, OPEN_FMODE(flags)); 1179 if (ret < 0) 1180 return ret; 1181 1182 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 1183 flags | O_CLOEXEC); 1184 } 1185 1186 int bpf_get_file_flag(int flags) 1187 { 1188 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 1189 return -EINVAL; 1190 if (flags & BPF_F_RDONLY) 1191 return O_RDONLY; 1192 if (flags & BPF_F_WRONLY) 1193 return O_WRONLY; 1194 return O_RDWR; 1195 } 1196 1197 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 1198 #define CHECK_ATTR(CMD) \ 1199 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 1200 sizeof(attr->CMD##_LAST_FIELD), 0, \ 1201 sizeof(*attr) - \ 1202 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 1203 sizeof(attr->CMD##_LAST_FIELD)) != NULL 1204 1205 /* dst and src must have at least "size" number of bytes. 1206 * Return strlen on success and < 0 on error. 1207 */ 1208 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 1209 { 1210 const char *end = src + size; 1211 const char *orig_src = src; 1212 1213 memset(dst, 0, size); 1214 /* Copy all isalnum(), '_' and '.' chars. */ 1215 while (src < end && *src) { 1216 if (!isalnum(*src) && 1217 *src != '_' && *src != '.') 1218 return -EINVAL; 1219 *dst++ = *src++; 1220 } 1221 1222 /* No '\0' found in "size" number of bytes */ 1223 if (src == end) 1224 return -EINVAL; 1225 1226 return src - orig_src; 1227 } 1228 EXPORT_SYMBOL_GPL(bpf_obj_name_cpy); 1229 1230 int map_check_no_btf(struct bpf_map *map, 1231 const struct btf *btf, 1232 const struct btf_type *key_type, 1233 const struct btf_type *value_type) 1234 { 1235 return -ENOTSUPP; 1236 } 1237 1238 static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 1239 const struct btf *btf, u32 btf_key_id, u32 btf_value_id) 1240 { 1241 const struct btf_type *key_type, *value_type; 1242 u32 key_size, value_size; 1243 int ret = 0; 1244 1245 /* Some maps allow key to be unspecified. */ 1246 if (btf_key_id) { 1247 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 1248 if (!key_type || key_size != map->key_size) 1249 return -EINVAL; 1250 } else { 1251 key_type = btf_type_by_id(btf, 0); 1252 if (!map->ops->map_check_btf) 1253 return -EINVAL; 1254 } 1255 1256 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 1257 if (!value_type || value_size != map->value_size) 1258 return -EINVAL; 1259 1260 map->record = btf_parse_fields(btf, value_type, 1261 BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | 1262 BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR | 1263 BPF_TASK_WORK, 1264 map->value_size); 1265 if (!IS_ERR_OR_NULL(map->record)) { 1266 int i; 1267 1268 if (!bpf_token_capable(token, CAP_BPF)) { 1269 ret = -EPERM; 1270 goto free_map_tab; 1271 } 1272 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { 1273 ret = -EACCES; 1274 goto free_map_tab; 1275 } 1276 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { 1277 switch (map->record->field_mask & (1 << i)) { 1278 case 0: 1279 continue; 1280 case BPF_SPIN_LOCK: 1281 case BPF_RES_SPIN_LOCK: 1282 if (map->map_type != BPF_MAP_TYPE_HASH && 1283 map->map_type != BPF_MAP_TYPE_ARRAY && 1284 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 1285 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1286 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1287 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1288 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1289 ret = -EOPNOTSUPP; 1290 goto free_map_tab; 1291 } 1292 break; 1293 case BPF_TIMER: 1294 case BPF_WORKQUEUE: 1295 case BPF_TASK_WORK: 1296 if (map->map_type != BPF_MAP_TYPE_HASH && 1297 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1298 map->map_type != BPF_MAP_TYPE_ARRAY) { 1299 ret = -EOPNOTSUPP; 1300 goto free_map_tab; 1301 } 1302 break; 1303 case BPF_KPTR_UNREF: 1304 case BPF_KPTR_REF: 1305 case BPF_KPTR_PERCPU: 1306 case BPF_REFCOUNT: 1307 if (map->map_type != BPF_MAP_TYPE_HASH && 1308 map->map_type != BPF_MAP_TYPE_PERCPU_HASH && 1309 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1310 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && 1311 map->map_type != BPF_MAP_TYPE_ARRAY && 1312 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && 1313 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1314 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1315 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1316 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1317 ret = -EOPNOTSUPP; 1318 goto free_map_tab; 1319 } 1320 break; 1321 case BPF_UPTR: 1322 if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) { 1323 ret = -EOPNOTSUPP; 1324 goto free_map_tab; 1325 } 1326 break; 1327 case BPF_LIST_HEAD: 1328 case BPF_RB_ROOT: 1329 if (map->map_type != BPF_MAP_TYPE_HASH && 1330 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1331 map->map_type != BPF_MAP_TYPE_ARRAY) { 1332 ret = -EOPNOTSUPP; 1333 goto free_map_tab; 1334 } 1335 break; 1336 default: 1337 /* Fail if map_type checks are missing for a field type */ 1338 ret = -EOPNOTSUPP; 1339 goto free_map_tab; 1340 } 1341 } 1342 } 1343 1344 ret = btf_check_and_fixup_fields(btf, map->record); 1345 if (ret < 0) 1346 goto free_map_tab; 1347 1348 if (map->ops->map_check_btf) { 1349 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 1350 if (ret < 0) 1351 goto free_map_tab; 1352 } 1353 1354 return ret; 1355 free_map_tab: 1356 bpf_map_free_record(map); 1357 return ret; 1358 } 1359 1360 #define BPF_MAP_CREATE_LAST_FIELD excl_prog_hash_size 1361 /* called via syscall */ 1362 static int map_create_alloc(union bpf_attr *attr, bpfptr_t uattr, struct bpf_verifier_log *log, 1363 struct bpf_map **mapp, struct bpf_token **tokenp) 1364 { 1365 const struct bpf_map_ops *ops; 1366 struct bpf_token *token = NULL; 1367 int numa_node = bpf_map_attr_numa_node(attr); 1368 u32 map_type = attr->map_type; 1369 struct bpf_map *map; 1370 bool token_flag; 1371 int err; 1372 1373 err = CHECK_ATTR(BPF_MAP_CREATE); 1374 if (err) { 1375 bpf_log(log, "Invalid attr.\n"); 1376 return -EINVAL; 1377 } 1378 1379 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it 1380 * to avoid per-map type checks tripping on unknown flag 1381 */ 1382 token_flag = attr->map_flags & BPF_F_TOKEN_FD; 1383 attr->map_flags &= ~BPF_F_TOKEN_FD; 1384 1385 if (attr->btf_vmlinux_value_type_id) { 1386 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS) { 1387 bpf_log(log, "btf_vmlinux_value_type_id can only be used with struct_ops maps.\n"); 1388 return -EINVAL; 1389 } 1390 if (attr->btf_key_type_id || attr->btf_value_type_id) { 1391 bpf_log(log, "btf_vmlinux_value_type_id is mutually exclusive with btf_key_type_id and btf_value_type_id.\n"); 1392 return -EINVAL; 1393 } 1394 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 1395 bpf_log(log, "Invalid btf_value_type_id.\n"); 1396 return -EINVAL; 1397 } 1398 1399 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 1400 attr->map_type != BPF_MAP_TYPE_ARENA && 1401 attr->map_extra != 0) { 1402 bpf_log(log, "Invalid map_extra.\n"); 1403 return -EINVAL; 1404 } 1405 1406 if (numa_node != NUMA_NO_NODE && 1407 ((unsigned int)numa_node >= nr_node_ids || 1408 !node_online(numa_node))) { 1409 bpf_log(log, "Invalid numa_node.\n"); 1410 return -EINVAL; 1411 } 1412 1413 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 1414 map_type = attr->map_type; 1415 if (map_type >= ARRAY_SIZE(bpf_map_types)) { 1416 bpf_log(log, "Invalid map_type.\n"); 1417 return -EINVAL; 1418 } 1419 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); 1420 ops = bpf_map_types[map_type]; 1421 if (!ops) 1422 return -EINVAL; 1423 1424 if (ops->map_alloc_check) { 1425 err = ops->map_alloc_check(attr); 1426 if (err) 1427 return err; 1428 } 1429 if (attr->map_ifindex) 1430 ops = &bpf_map_offload_ops; 1431 if (!ops->map_mem_usage) 1432 return -EINVAL; 1433 1434 if (token_flag) { 1435 token = bpf_token_get_from_fd(attr->map_token_fd); 1436 if (IS_ERR(token)) { 1437 bpf_log(log, "Invalid map_token_fd.\n"); 1438 return PTR_ERR(token); 1439 } 1440 1441 /* if current token doesn't grant map creation permissions, 1442 * then we can't use this token, so ignore it and rely on 1443 * system-wide capabilities checks 1444 */ 1445 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || 1446 !bpf_token_allow_map_type(token, attr->map_type)) { 1447 bpf_token_put(token); 1448 token = NULL; 1449 } 1450 } 1451 1452 err = -EPERM; 1453 1454 /* Intent here is for unprivileged_bpf_disabled to block BPF map 1455 * creation for unprivileged users; other actions depend 1456 * on fd availability and access to bpffs, so are dependent on 1457 * object creation success. Even with unprivileged BPF disabled, 1458 * capability checks are still carried out. 1459 */ 1460 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) 1461 goto put_token; 1462 1463 /* check privileged map type permissions */ 1464 switch (map_type) { 1465 case BPF_MAP_TYPE_ARRAY: 1466 case BPF_MAP_TYPE_PERCPU_ARRAY: 1467 case BPF_MAP_TYPE_PROG_ARRAY: 1468 case BPF_MAP_TYPE_PERF_EVENT_ARRAY: 1469 case BPF_MAP_TYPE_CGROUP_ARRAY: 1470 case BPF_MAP_TYPE_ARRAY_OF_MAPS: 1471 case BPF_MAP_TYPE_HASH: 1472 case BPF_MAP_TYPE_PERCPU_HASH: 1473 case BPF_MAP_TYPE_HASH_OF_MAPS: 1474 case BPF_MAP_TYPE_RINGBUF: 1475 case BPF_MAP_TYPE_USER_RINGBUF: 1476 case BPF_MAP_TYPE_CGROUP_STORAGE: 1477 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: 1478 /* unprivileged */ 1479 break; 1480 case BPF_MAP_TYPE_SK_STORAGE: 1481 case BPF_MAP_TYPE_INODE_STORAGE: 1482 case BPF_MAP_TYPE_TASK_STORAGE: 1483 case BPF_MAP_TYPE_CGRP_STORAGE: 1484 case BPF_MAP_TYPE_BLOOM_FILTER: 1485 case BPF_MAP_TYPE_LPM_TRIE: 1486 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: 1487 case BPF_MAP_TYPE_STACK_TRACE: 1488 case BPF_MAP_TYPE_QUEUE: 1489 case BPF_MAP_TYPE_STACK: 1490 case BPF_MAP_TYPE_LRU_HASH: 1491 case BPF_MAP_TYPE_LRU_PERCPU_HASH: 1492 case BPF_MAP_TYPE_STRUCT_OPS: 1493 case BPF_MAP_TYPE_CPUMAP: 1494 case BPF_MAP_TYPE_ARENA: 1495 case BPF_MAP_TYPE_INSN_ARRAY: 1496 if (!bpf_token_capable(token, CAP_BPF)) 1497 goto put_token; 1498 break; 1499 case BPF_MAP_TYPE_SOCKMAP: 1500 case BPF_MAP_TYPE_SOCKHASH: 1501 case BPF_MAP_TYPE_DEVMAP: 1502 case BPF_MAP_TYPE_DEVMAP_HASH: 1503 case BPF_MAP_TYPE_XSKMAP: 1504 if (!bpf_token_capable(token, CAP_NET_ADMIN)) 1505 goto put_token; 1506 break; 1507 default: 1508 WARN(1, "unsupported map type %d", map_type); 1509 goto put_token; 1510 } 1511 1512 map = ops->map_alloc(attr); 1513 if (IS_ERR(map)) { 1514 err = PTR_ERR(map); 1515 goto put_token; 1516 } 1517 map->ops = ops; 1518 map->map_type = map_type; 1519 1520 err = bpf_obj_name_cpy(map->name, attr->map_name, 1521 sizeof(attr->map_name)); 1522 if (err < 0) { 1523 bpf_log(log, "Invalid map_name.\n"); 1524 goto free_map; 1525 } 1526 1527 preempt_disable(); 1528 map->cookie = gen_cookie_next(&bpf_map_cookie); 1529 preempt_enable(); 1530 1531 atomic64_set(&map->refcnt, 1); 1532 atomic64_set(&map->usercnt, 1); 1533 mutex_init(&map->freeze_mutex); 1534 spin_lock_init(&map->owner_lock); 1535 1536 if (attr->btf_key_type_id || attr->btf_value_type_id || 1537 /* Even the map's value is a kernel's struct, 1538 * the bpf_prog.o must have BTF to begin with 1539 * to figure out the corresponding kernel's 1540 * counter part. Thus, attr->btf_fd has 1541 * to be valid also. 1542 */ 1543 attr->btf_vmlinux_value_type_id) { 1544 struct btf *btf; 1545 1546 btf = btf_get_by_fd(attr->btf_fd); 1547 if (IS_ERR(btf)) { 1548 bpf_log(log, "Invalid btf_fd.\n"); 1549 err = PTR_ERR(btf); 1550 goto free_map; 1551 } 1552 if (btf_is_kernel(btf)) { 1553 btf_put(btf); 1554 err = -EACCES; 1555 goto free_map; 1556 } 1557 map->btf = btf; 1558 1559 if (attr->btf_value_type_id) { 1560 err = map_check_btf(map, token, btf, attr->btf_key_type_id, 1561 attr->btf_value_type_id); 1562 if (err) 1563 goto free_map; 1564 } 1565 1566 map->btf_key_type_id = attr->btf_key_type_id; 1567 map->btf_value_type_id = attr->btf_value_type_id; 1568 map->btf_vmlinux_value_type_id = 1569 attr->btf_vmlinux_value_type_id; 1570 } 1571 1572 if (attr->excl_prog_hash) { 1573 bpfptr_t uprog_hash = make_bpfptr(attr->excl_prog_hash, uattr.is_kernel); 1574 1575 if (attr->excl_prog_hash_size != SHA256_DIGEST_SIZE) { 1576 bpf_log(log, "Invalid excl_prog_hash_size.\n"); 1577 err = -EINVAL; 1578 goto free_map; 1579 } 1580 1581 map->excl_prog_sha = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); 1582 if (!map->excl_prog_sha) { 1583 err = -ENOMEM; 1584 goto free_map; 1585 } 1586 1587 if (copy_from_bpfptr(map->excl_prog_sha, uprog_hash, SHA256_DIGEST_SIZE)) { 1588 err = -EFAULT; 1589 goto free_map; 1590 } 1591 } else if (attr->excl_prog_hash_size) { 1592 bpf_log(log, "Invalid excl_prog_hash_size.\n"); 1593 err = -EINVAL; 1594 goto free_map; 1595 } 1596 1597 *mapp = map; 1598 *tokenp = token; 1599 return 0; 1600 1601 free_map: 1602 bpf_map_free(map); 1603 put_token: 1604 bpf_token_put(token); 1605 return err; 1606 } 1607 1608 static int map_create(union bpf_attr *attr, bpfptr_t uattr, struct bpf_common_attr *attr_common, 1609 bpfptr_t uattr_common, u32 size_common) 1610 { 1611 struct bpf_token *token = NULL; 1612 struct bpf_verifier_log *log; 1613 struct bpf_log_attr attr_log; 1614 struct bpf_map *map = NULL; 1615 int err, ret; 1616 int f_flags; 1617 1618 log = bpf_log_attr_create_vlog(&attr_log, attr_common, uattr_common, size_common); 1619 if (IS_ERR(log)) 1620 return PTR_ERR(log); 1621 1622 err = map_create_alloc(attr, uattr, log, &map, &token); 1623 1624 /* preserve original error even if log finalization is successful */ 1625 ret = bpf_log_attr_finalize(&attr_log, log); 1626 if (ret) 1627 err = ret; 1628 1629 kfree(log); 1630 1631 if (err) 1632 goto free_map; 1633 1634 f_flags = bpf_get_file_flag(attr->map_flags); 1635 if (f_flags < 0) { 1636 err = f_flags; 1637 goto free_map; 1638 } 1639 1640 err = security_bpf_map_create(map, attr, token, uattr.is_kernel); 1641 if (err) 1642 goto free_map_sec; 1643 1644 err = bpf_map_alloc_id(map); 1645 if (err) 1646 goto free_map_sec; 1647 1648 bpf_map_save_memcg(map); 1649 bpf_token_put(token); 1650 1651 err = bpf_map_new_fd(map, f_flags); 1652 if (err < 0) { 1653 /* failed to allocate fd. 1654 * bpf_map_put_with_uref() is needed because the above 1655 * bpf_map_alloc_id() has published the map 1656 * to the userspace and the userspace may 1657 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 1658 */ 1659 bpf_map_put_with_uref(map); 1660 return err; 1661 } 1662 1663 return err; 1664 1665 free_map_sec: 1666 security_bpf_map_free(map); 1667 free_map: 1668 if (map) 1669 bpf_map_free(map); 1670 bpf_token_put(token); 1671 return err; 1672 } 1673 1674 void bpf_map_inc(struct bpf_map *map) 1675 { 1676 atomic64_inc(&map->refcnt); 1677 } 1678 EXPORT_SYMBOL_GPL(bpf_map_inc); 1679 1680 void bpf_map_inc_with_uref(struct bpf_map *map) 1681 { 1682 atomic64_inc(&map->refcnt); 1683 atomic64_inc(&map->usercnt); 1684 } 1685 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 1686 1687 struct bpf_map *bpf_map_get(u32 ufd) 1688 { 1689 CLASS(fd, f)(ufd); 1690 struct bpf_map *map = __bpf_map_get(f); 1691 1692 if (!IS_ERR(map)) 1693 bpf_map_inc(map); 1694 1695 return map; 1696 } 1697 EXPORT_SYMBOL_NS(bpf_map_get, "BPF_INTERNAL"); 1698 1699 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 1700 { 1701 CLASS(fd, f)(ufd); 1702 struct bpf_map *map = __bpf_map_get(f); 1703 1704 if (!IS_ERR(map)) 1705 bpf_map_inc_with_uref(map); 1706 1707 return map; 1708 } 1709 1710 /* map_idr_lock should have been held or the map should have been 1711 * protected by rcu read lock. 1712 */ 1713 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1714 { 1715 int refold; 1716 1717 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1718 if (!refold) 1719 return ERR_PTR(-ENOENT); 1720 if (uref) 1721 atomic64_inc(&map->usercnt); 1722 1723 return map; 1724 } 1725 1726 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1727 { 1728 lockdep_assert(rcu_read_lock_held()); 1729 return __bpf_map_inc_not_zero(map, false); 1730 } 1731 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1732 1733 int __weak bpf_stackmap_extract(struct bpf_map *map, void *key, void *value, 1734 bool delete) 1735 { 1736 return -ENOTSUPP; 1737 } 1738 1739 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1740 { 1741 if (key_size) 1742 return vmemdup_user(ukey, key_size); 1743 1744 if (ukey) 1745 return ERR_PTR(-EINVAL); 1746 1747 return NULL; 1748 } 1749 1750 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1751 { 1752 if (key_size) 1753 return kvmemdup_bpfptr(ukey, key_size); 1754 1755 if (!bpfptr_is_null(ukey)) 1756 return ERR_PTR(-EINVAL); 1757 1758 return NULL; 1759 } 1760 1761 /* last field in 'union bpf_attr' used by this command */ 1762 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1763 1764 static int map_lookup_elem(union bpf_attr *attr) 1765 { 1766 void __user *ukey = u64_to_user_ptr(attr->key); 1767 void __user *uvalue = u64_to_user_ptr(attr->value); 1768 struct bpf_map *map; 1769 void *key, *value; 1770 u32 value_size; 1771 int err; 1772 1773 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1774 return -EINVAL; 1775 1776 CLASS(fd, f)(attr->map_fd); 1777 map = __bpf_map_get(f); 1778 if (IS_ERR(map)) 1779 return PTR_ERR(map); 1780 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1781 return -EPERM; 1782 1783 err = bpf_map_check_op_flags(map, attr->flags, BPF_F_LOCK | BPF_F_CPU); 1784 if (err) 1785 return err; 1786 1787 key = __bpf_copy_key(ukey, map->key_size); 1788 if (IS_ERR(key)) 1789 return PTR_ERR(key); 1790 1791 value_size = bpf_map_value_size(map, attr->flags); 1792 1793 err = -ENOMEM; 1794 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1795 if (!value) 1796 goto free_key; 1797 1798 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1799 if (copy_from_user(value, uvalue, value_size)) 1800 err = -EFAULT; 1801 else 1802 err = bpf_map_copy_value(map, key, value, attr->flags); 1803 goto free_value; 1804 } 1805 1806 err = bpf_map_copy_value(map, key, value, attr->flags); 1807 if (err) 1808 goto free_value; 1809 1810 err = -EFAULT; 1811 if (copy_to_user(uvalue, value, value_size) != 0) 1812 goto free_value; 1813 1814 err = 0; 1815 1816 free_value: 1817 kvfree(value); 1818 free_key: 1819 kvfree(key); 1820 return err; 1821 } 1822 1823 1824 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1825 1826 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1827 { 1828 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1829 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1830 struct bpf_map *map; 1831 void *key, *value; 1832 u32 value_size; 1833 int err; 1834 1835 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1836 return -EINVAL; 1837 1838 CLASS(fd, f)(attr->map_fd); 1839 map = __bpf_map_get(f); 1840 if (IS_ERR(map)) 1841 return PTR_ERR(map); 1842 bpf_map_write_active_inc(map); 1843 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1844 err = -EPERM; 1845 goto err_put; 1846 } 1847 1848 err = bpf_map_check_op_flags(map, attr->flags, ~0); 1849 if (err) 1850 goto err_put; 1851 1852 key = ___bpf_copy_key(ukey, map->key_size); 1853 if (IS_ERR(key)) { 1854 err = PTR_ERR(key); 1855 goto err_put; 1856 } 1857 1858 value_size = bpf_map_value_size(map, attr->flags); 1859 value = kvmemdup_bpfptr(uvalue, value_size); 1860 if (IS_ERR(value)) { 1861 err = PTR_ERR(value); 1862 goto free_key; 1863 } 1864 1865 err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags); 1866 if (!err) 1867 maybe_wait_bpf_programs(map); 1868 1869 kvfree(value); 1870 free_key: 1871 kvfree(key); 1872 err_put: 1873 bpf_map_write_active_dec(map); 1874 return err; 1875 } 1876 1877 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1878 1879 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) 1880 { 1881 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1882 struct bpf_map *map; 1883 void *key; 1884 int err; 1885 1886 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1887 return -EINVAL; 1888 1889 CLASS(fd, f)(attr->map_fd); 1890 map = __bpf_map_get(f); 1891 if (IS_ERR(map)) 1892 return PTR_ERR(map); 1893 bpf_map_write_active_inc(map); 1894 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1895 err = -EPERM; 1896 goto err_put; 1897 } 1898 1899 key = ___bpf_copy_key(ukey, map->key_size); 1900 if (IS_ERR(key)) { 1901 err = PTR_ERR(key); 1902 goto err_put; 1903 } 1904 1905 if (bpf_map_is_offloaded(map)) { 1906 err = bpf_map_offload_delete_elem(map, key); 1907 goto out; 1908 } else if (IS_FD_PROG_ARRAY(map) || 1909 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1910 /* These maps require sleepable context */ 1911 err = map->ops->map_delete_elem(map, key); 1912 goto out; 1913 } 1914 1915 bpf_disable_instrumentation(); 1916 rcu_read_lock(); 1917 err = map->ops->map_delete_elem(map, key); 1918 rcu_read_unlock(); 1919 bpf_enable_instrumentation(); 1920 if (!err) 1921 maybe_wait_bpf_programs(map); 1922 out: 1923 kvfree(key); 1924 err_put: 1925 bpf_map_write_active_dec(map); 1926 return err; 1927 } 1928 1929 /* last field in 'union bpf_attr' used by this command */ 1930 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1931 1932 static int map_get_next_key(union bpf_attr *attr) 1933 { 1934 void __user *ukey = u64_to_user_ptr(attr->key); 1935 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1936 struct bpf_map *map; 1937 void *key, *next_key; 1938 int err; 1939 1940 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1941 return -EINVAL; 1942 1943 CLASS(fd, f)(attr->map_fd); 1944 map = __bpf_map_get(f); 1945 if (IS_ERR(map)) 1946 return PTR_ERR(map); 1947 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1948 return -EPERM; 1949 1950 if (ukey) { 1951 key = __bpf_copy_key(ukey, map->key_size); 1952 if (IS_ERR(key)) 1953 return PTR_ERR(key); 1954 } else { 1955 key = NULL; 1956 } 1957 1958 err = -ENOMEM; 1959 next_key = kvmalloc(map->key_size, GFP_USER); 1960 if (!next_key) 1961 goto free_key; 1962 1963 if (bpf_map_is_offloaded(map)) { 1964 err = bpf_map_offload_get_next_key(map, key, next_key); 1965 goto out; 1966 } 1967 1968 rcu_read_lock(); 1969 err = map->ops->map_get_next_key(map, key, next_key); 1970 rcu_read_unlock(); 1971 out: 1972 if (err) 1973 goto free_next_key; 1974 1975 err = -EFAULT; 1976 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1977 goto free_next_key; 1978 1979 err = 0; 1980 1981 free_next_key: 1982 kvfree(next_key); 1983 free_key: 1984 kvfree(key); 1985 return err; 1986 } 1987 1988 int generic_map_delete_batch(struct bpf_map *map, 1989 const union bpf_attr *attr, 1990 union bpf_attr __user *uattr) 1991 { 1992 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1993 u32 cp, max_count; 1994 int err = 0; 1995 void *key; 1996 1997 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1998 return -EINVAL; 1999 2000 if ((attr->batch.elem_flags & BPF_F_LOCK) && 2001 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2002 return -EINVAL; 2003 } 2004 2005 max_count = attr->batch.count; 2006 if (!max_count) 2007 return 0; 2008 2009 if (put_user(0, &uattr->batch.count)) 2010 return -EFAULT; 2011 2012 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2013 if (!key) 2014 return -ENOMEM; 2015 2016 for (cp = 0; cp < max_count; cp++) { 2017 err = -EFAULT; 2018 if (copy_from_user(key, keys + cp * map->key_size, 2019 map->key_size)) 2020 break; 2021 2022 if (bpf_map_is_offloaded(map)) { 2023 err = bpf_map_offload_delete_elem(map, key); 2024 break; 2025 } 2026 2027 bpf_disable_instrumentation(); 2028 rcu_read_lock(); 2029 err = map->ops->map_delete_elem(map, key); 2030 rcu_read_unlock(); 2031 bpf_enable_instrumentation(); 2032 if (err) 2033 break; 2034 cond_resched(); 2035 } 2036 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 2037 err = -EFAULT; 2038 2039 kvfree(key); 2040 2041 return err; 2042 } 2043 2044 int generic_map_update_batch(struct bpf_map *map, struct file *map_file, 2045 const union bpf_attr *attr, 2046 union bpf_attr __user *uattr) 2047 { 2048 void __user *values = u64_to_user_ptr(attr->batch.values); 2049 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2050 u32 value_size, cp, max_count; 2051 void *key, *value; 2052 int err = 0; 2053 2054 err = bpf_map_check_op_flags(map, attr->batch.elem_flags, 2055 BPF_F_LOCK | BPF_F_CPU | BPF_F_ALL_CPUS); 2056 if (err) 2057 return err; 2058 2059 value_size = bpf_map_value_size(map, attr->batch.elem_flags); 2060 2061 max_count = attr->batch.count; 2062 if (!max_count) 2063 return 0; 2064 2065 if (put_user(0, &uattr->batch.count)) 2066 return -EFAULT; 2067 2068 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2069 if (!key) 2070 return -ENOMEM; 2071 2072 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2073 if (!value) { 2074 kvfree(key); 2075 return -ENOMEM; 2076 } 2077 2078 for (cp = 0; cp < max_count; cp++) { 2079 err = -EFAULT; 2080 if (copy_from_user(key, keys + cp * map->key_size, 2081 map->key_size) || 2082 copy_from_user(value, values + cp * value_size, value_size)) 2083 break; 2084 2085 err = bpf_map_update_value(map, map_file, key, value, 2086 attr->batch.elem_flags); 2087 2088 if (err) 2089 break; 2090 cond_resched(); 2091 } 2092 2093 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 2094 err = -EFAULT; 2095 2096 kvfree(value); 2097 kvfree(key); 2098 2099 return err; 2100 } 2101 2102 int generic_map_lookup_batch(struct bpf_map *map, 2103 const union bpf_attr *attr, 2104 union bpf_attr __user *uattr) 2105 { 2106 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 2107 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 2108 void __user *values = u64_to_user_ptr(attr->batch.values); 2109 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2110 void *buf, *buf_prevkey, *prev_key, *key, *value; 2111 u32 value_size, cp, max_count; 2112 int err; 2113 2114 err = bpf_map_check_op_flags(map, attr->batch.elem_flags, BPF_F_LOCK | BPF_F_CPU); 2115 if (err) 2116 return err; 2117 2118 value_size = bpf_map_value_size(map, attr->batch.elem_flags); 2119 2120 max_count = attr->batch.count; 2121 if (!max_count) 2122 return 0; 2123 2124 if (put_user(0, &uattr->batch.count)) 2125 return -EFAULT; 2126 2127 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2128 if (!buf_prevkey) 2129 return -ENOMEM; 2130 2131 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 2132 if (!buf) { 2133 kvfree(buf_prevkey); 2134 return -ENOMEM; 2135 } 2136 2137 err = -EFAULT; 2138 prev_key = NULL; 2139 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 2140 goto free_buf; 2141 key = buf; 2142 value = key + map->key_size; 2143 if (ubatch) 2144 prev_key = buf_prevkey; 2145 2146 for (cp = 0; cp < max_count;) { 2147 rcu_read_lock(); 2148 err = map->ops->map_get_next_key(map, prev_key, key); 2149 rcu_read_unlock(); 2150 if (err) 2151 break; 2152 err = bpf_map_copy_value(map, key, value, 2153 attr->batch.elem_flags); 2154 2155 if (err == -ENOENT) 2156 goto next_key; 2157 2158 if (err) 2159 goto free_buf; 2160 2161 if (copy_to_user(keys + cp * map->key_size, key, 2162 map->key_size)) { 2163 err = -EFAULT; 2164 goto free_buf; 2165 } 2166 if (copy_to_user(values + cp * value_size, value, value_size)) { 2167 err = -EFAULT; 2168 goto free_buf; 2169 } 2170 2171 cp++; 2172 next_key: 2173 if (!prev_key) 2174 prev_key = buf_prevkey; 2175 2176 swap(prev_key, key); 2177 cond_resched(); 2178 } 2179 2180 if (err == -EFAULT) 2181 goto free_buf; 2182 2183 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 2184 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 2185 err = -EFAULT; 2186 2187 free_buf: 2188 kvfree(buf_prevkey); 2189 kvfree(buf); 2190 return err; 2191 } 2192 2193 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 2194 2195 static int map_lookup_and_delete_elem(union bpf_attr *attr) 2196 { 2197 void __user *ukey = u64_to_user_ptr(attr->key); 2198 void __user *uvalue = u64_to_user_ptr(attr->value); 2199 struct bpf_map *map; 2200 void *key, *value; 2201 u32 value_size; 2202 int err; 2203 2204 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 2205 return -EINVAL; 2206 2207 if (attr->flags & ~BPF_F_LOCK) 2208 return -EINVAL; 2209 2210 CLASS(fd, f)(attr->map_fd); 2211 map = __bpf_map_get(f); 2212 if (IS_ERR(map)) 2213 return PTR_ERR(map); 2214 bpf_map_write_active_inc(map); 2215 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 2216 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 2217 err = -EPERM; 2218 goto err_put; 2219 } 2220 2221 if (attr->flags && 2222 (map->map_type == BPF_MAP_TYPE_QUEUE || 2223 map->map_type == BPF_MAP_TYPE_STACK)) { 2224 err = -EINVAL; 2225 goto err_put; 2226 } 2227 2228 if ((attr->flags & BPF_F_LOCK) && 2229 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2230 err = -EINVAL; 2231 goto err_put; 2232 } 2233 2234 key = __bpf_copy_key(ukey, map->key_size); 2235 if (IS_ERR(key)) { 2236 err = PTR_ERR(key); 2237 goto err_put; 2238 } 2239 2240 value_size = bpf_map_value_size(map, 0); 2241 2242 err = -ENOMEM; 2243 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2244 if (!value) 2245 goto free_key; 2246 2247 err = -ENOTSUPP; 2248 if (map->map_type == BPF_MAP_TYPE_QUEUE || 2249 map->map_type == BPF_MAP_TYPE_STACK) { 2250 err = map->ops->map_pop_elem(map, value); 2251 } else if (map->map_type == BPF_MAP_TYPE_HASH || 2252 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 2253 map->map_type == BPF_MAP_TYPE_LRU_HASH || 2254 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 2255 map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 2256 if (!bpf_map_is_offloaded(map)) { 2257 bpf_disable_instrumentation(); 2258 rcu_read_lock(); 2259 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 2260 rcu_read_unlock(); 2261 bpf_enable_instrumentation(); 2262 } 2263 } 2264 2265 if (err) 2266 goto free_value; 2267 2268 if (copy_to_user(uvalue, value, value_size) != 0) { 2269 err = -EFAULT; 2270 goto free_value; 2271 } 2272 2273 err = 0; 2274 2275 free_value: 2276 kvfree(value); 2277 free_key: 2278 kvfree(key); 2279 err_put: 2280 bpf_map_write_active_dec(map); 2281 return err; 2282 } 2283 2284 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 2285 2286 static int map_freeze(const union bpf_attr *attr) 2287 { 2288 int err = 0; 2289 struct bpf_map *map; 2290 2291 if (CHECK_ATTR(BPF_MAP_FREEZE)) 2292 return -EINVAL; 2293 2294 CLASS(fd, f)(attr->map_fd); 2295 map = __bpf_map_get(f); 2296 if (IS_ERR(map)) 2297 return PTR_ERR(map); 2298 2299 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) 2300 return -ENOTSUPP; 2301 2302 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) 2303 return -EPERM; 2304 2305 mutex_lock(&map->freeze_mutex); 2306 if (bpf_map_write_active(map)) { 2307 err = -EBUSY; 2308 goto err_put; 2309 } 2310 if (READ_ONCE(map->frozen)) { 2311 err = -EBUSY; 2312 goto err_put; 2313 } 2314 2315 WRITE_ONCE(map->frozen, true); 2316 err_put: 2317 mutex_unlock(&map->freeze_mutex); 2318 return err; 2319 } 2320 2321 static const struct bpf_prog_ops * const bpf_prog_types[] = { 2322 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 2323 [_id] = & _name ## _prog_ops, 2324 #define BPF_MAP_TYPE(_id, _ops) 2325 #define BPF_LINK_TYPE(_id, _name) 2326 #include <linux/bpf_types.h> 2327 #undef BPF_PROG_TYPE 2328 #undef BPF_MAP_TYPE 2329 #undef BPF_LINK_TYPE 2330 }; 2331 2332 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 2333 { 2334 const struct bpf_prog_ops *ops; 2335 2336 if (type >= ARRAY_SIZE(bpf_prog_types)) 2337 return -EINVAL; 2338 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 2339 ops = bpf_prog_types[type]; 2340 if (!ops) 2341 return -EINVAL; 2342 2343 if (!bpf_prog_is_offloaded(prog->aux)) 2344 prog->aux->ops = ops; 2345 else 2346 prog->aux->ops = &bpf_offload_prog_ops; 2347 prog->type = type; 2348 return 0; 2349 } 2350 2351 enum bpf_audit { 2352 BPF_AUDIT_LOAD, 2353 BPF_AUDIT_UNLOAD, 2354 BPF_AUDIT_MAX, 2355 }; 2356 2357 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 2358 [BPF_AUDIT_LOAD] = "LOAD", 2359 [BPF_AUDIT_UNLOAD] = "UNLOAD", 2360 }; 2361 2362 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 2363 { 2364 struct audit_context *ctx = NULL; 2365 struct audit_buffer *ab; 2366 2367 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 2368 return; 2369 if (audit_enabled == AUDIT_OFF) 2370 return; 2371 if (!in_hardirq() && !irqs_disabled()) 2372 ctx = audit_context(); 2373 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 2374 if (unlikely(!ab)) 2375 return; 2376 audit_log_format(ab, "prog-id=%u op=%s", 2377 prog->aux->id, bpf_audit_str[op]); 2378 audit_log_end(ab); 2379 } 2380 2381 static int bpf_prog_alloc_id(struct bpf_prog *prog) 2382 { 2383 int id; 2384 2385 idr_preload(GFP_KERNEL); 2386 spin_lock_bh(&prog_idr_lock); 2387 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 2388 if (id > 0) 2389 prog->aux->id = id; 2390 spin_unlock_bh(&prog_idr_lock); 2391 idr_preload_end(); 2392 2393 /* id is in [1, INT_MAX) */ 2394 if (WARN_ON_ONCE(!id)) 2395 return -ENOSPC; 2396 2397 return id > 0 ? 0 : id; 2398 } 2399 2400 void bpf_prog_free_id(struct bpf_prog *prog) 2401 { 2402 unsigned long flags; 2403 2404 /* cBPF to eBPF migrations are currently not in the idr store. 2405 * Offloaded programs are removed from the store when their device 2406 * disappears - even if someone grabs an fd to them they are unusable, 2407 * simply waiting for refcnt to drop to be freed. 2408 */ 2409 if (!prog->aux->id) 2410 return; 2411 2412 spin_lock_irqsave(&prog_idr_lock, flags); 2413 idr_remove(&prog_idr, prog->aux->id); 2414 prog->aux->id = 0; 2415 spin_unlock_irqrestore(&prog_idr_lock, flags); 2416 } 2417 2418 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 2419 { 2420 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 2421 2422 kvfree(aux->func_info); 2423 kfree(aux->func_info_aux); 2424 free_uid(aux->user); 2425 security_bpf_prog_free(aux->prog); 2426 bpf_prog_free(aux->prog); 2427 } 2428 2429 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 2430 { 2431 bpf_prog_kallsyms_del_all(prog); 2432 btf_put(prog->aux->btf); 2433 module_put(prog->aux->mod); 2434 kvfree(prog->aux->jited_linfo); 2435 kvfree(prog->aux->linfo); 2436 kfree(prog->aux->kfunc_tab); 2437 kfree(prog->aux->ctx_arg_info); 2438 if (prog->aux->attach_btf) 2439 btf_put(prog->aux->attach_btf); 2440 2441 if (deferred) { 2442 if (prog->sleepable) 2443 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 2444 else 2445 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 2446 } else { 2447 __bpf_prog_put_rcu(&prog->aux->rcu); 2448 } 2449 } 2450 2451 static void bpf_prog_put_deferred(struct work_struct *work) 2452 { 2453 struct bpf_prog_aux *aux; 2454 struct bpf_prog *prog; 2455 2456 aux = container_of(work, struct bpf_prog_aux, work); 2457 prog = aux->prog; 2458 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 2459 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 2460 bpf_prog_free_id(prog); 2461 __bpf_prog_put_noref(prog, true); 2462 } 2463 2464 static void __bpf_prog_put(struct bpf_prog *prog) 2465 { 2466 struct bpf_prog_aux *aux = prog->aux; 2467 2468 if (atomic64_dec_and_test(&aux->refcnt)) { 2469 if (in_hardirq() || irqs_disabled()) { 2470 INIT_WORK(&aux->work, bpf_prog_put_deferred); 2471 schedule_work(&aux->work); 2472 } else { 2473 bpf_prog_put_deferred(&aux->work); 2474 } 2475 } 2476 } 2477 2478 void bpf_prog_put(struct bpf_prog *prog) 2479 { 2480 __bpf_prog_put(prog); 2481 } 2482 EXPORT_SYMBOL_GPL(bpf_prog_put); 2483 2484 static int bpf_prog_release(struct inode *inode, struct file *filp) 2485 { 2486 struct bpf_prog *prog = filp->private_data; 2487 2488 bpf_prog_put(prog); 2489 return 0; 2490 } 2491 2492 struct bpf_prog_kstats { 2493 u64 nsecs; 2494 u64 cnt; 2495 u64 misses; 2496 }; 2497 2498 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) 2499 { 2500 struct bpf_prog_stats *stats; 2501 unsigned int flags; 2502 2503 if (unlikely(!prog->stats)) 2504 return; 2505 2506 stats = this_cpu_ptr(prog->stats); 2507 flags = u64_stats_update_begin_irqsave(&stats->syncp); 2508 u64_stats_inc(&stats->misses); 2509 u64_stats_update_end_irqrestore(&stats->syncp, flags); 2510 } 2511 2512 static void bpf_prog_get_stats(const struct bpf_prog *prog, 2513 struct bpf_prog_kstats *stats) 2514 { 2515 u64 nsecs = 0, cnt = 0, misses = 0; 2516 int cpu; 2517 2518 for_each_possible_cpu(cpu) { 2519 const struct bpf_prog_stats *st; 2520 unsigned int start; 2521 u64 tnsecs, tcnt, tmisses; 2522 2523 st = per_cpu_ptr(prog->stats, cpu); 2524 do { 2525 start = u64_stats_fetch_begin(&st->syncp); 2526 tnsecs = u64_stats_read(&st->nsecs); 2527 tcnt = u64_stats_read(&st->cnt); 2528 tmisses = u64_stats_read(&st->misses); 2529 } while (u64_stats_fetch_retry(&st->syncp, start)); 2530 nsecs += tnsecs; 2531 cnt += tcnt; 2532 misses += tmisses; 2533 } 2534 stats->nsecs = nsecs; 2535 stats->cnt = cnt; 2536 stats->misses = misses; 2537 } 2538 2539 #ifdef CONFIG_PROC_FS 2540 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 2541 { 2542 const struct bpf_prog *prog = filp->private_data; 2543 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2544 struct bpf_prog_kstats stats; 2545 2546 bpf_prog_get_stats(prog, &stats); 2547 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2548 seq_printf(m, 2549 "prog_type:\t%u\n" 2550 "prog_jited:\t%u\n" 2551 "prog_tag:\t%s\n" 2552 "memlock:\t%llu\n" 2553 "prog_id:\t%u\n" 2554 "run_time_ns:\t%llu\n" 2555 "run_cnt:\t%llu\n" 2556 "recursion_misses:\t%llu\n" 2557 "verified_insns:\t%u\n", 2558 prog->type, 2559 prog->jited, 2560 prog_tag, 2561 prog->pages * 1ULL << PAGE_SHIFT, 2562 prog->aux->id, 2563 stats.nsecs, 2564 stats.cnt, 2565 stats.misses, 2566 prog->aux->verified_insns); 2567 } 2568 #endif 2569 2570 const struct file_operations bpf_prog_fops = { 2571 #ifdef CONFIG_PROC_FS 2572 .show_fdinfo = bpf_prog_show_fdinfo, 2573 #endif 2574 .release = bpf_prog_release, 2575 .read = bpf_dummy_read, 2576 .write = bpf_dummy_write, 2577 }; 2578 2579 int bpf_prog_new_fd(struct bpf_prog *prog) 2580 { 2581 int ret; 2582 2583 ret = security_bpf_prog(prog); 2584 if (ret < 0) 2585 return ret; 2586 2587 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 2588 O_RDWR | O_CLOEXEC); 2589 } 2590 2591 void bpf_prog_add(struct bpf_prog *prog, int i) 2592 { 2593 atomic64_add(i, &prog->aux->refcnt); 2594 } 2595 EXPORT_SYMBOL_GPL(bpf_prog_add); 2596 2597 void bpf_prog_sub(struct bpf_prog *prog, int i) 2598 { 2599 /* Only to be used for undoing previous bpf_prog_add() in some 2600 * error path. We still know that another entity in our call 2601 * path holds a reference to the program, thus atomic_sub() can 2602 * be safely used in such cases! 2603 */ 2604 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 2605 } 2606 EXPORT_SYMBOL_GPL(bpf_prog_sub); 2607 2608 void bpf_prog_inc(struct bpf_prog *prog) 2609 { 2610 atomic64_inc(&prog->aux->refcnt); 2611 } 2612 EXPORT_SYMBOL_GPL(bpf_prog_inc); 2613 2614 /* prog_idr_lock should have been held */ 2615 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 2616 { 2617 int refold; 2618 2619 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 2620 2621 if (!refold) 2622 return ERR_PTR(-ENOENT); 2623 2624 return prog; 2625 } 2626 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 2627 2628 bool bpf_prog_get_ok(struct bpf_prog *prog, 2629 enum bpf_prog_type *attach_type, bool attach_drv) 2630 { 2631 /* not an attachment, just a refcount inc, always allow */ 2632 if (!attach_type) 2633 return true; 2634 2635 if (prog->type != *attach_type) 2636 return false; 2637 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) 2638 return false; 2639 2640 return true; 2641 } 2642 2643 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 2644 bool attach_drv) 2645 { 2646 CLASS(fd, f)(ufd); 2647 struct bpf_prog *prog; 2648 2649 if (fd_empty(f)) 2650 return ERR_PTR(-EBADF); 2651 if (fd_file(f)->f_op != &bpf_prog_fops) 2652 return ERR_PTR(-EINVAL); 2653 2654 prog = fd_file(f)->private_data; 2655 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) 2656 return ERR_PTR(-EINVAL); 2657 2658 bpf_prog_inc(prog); 2659 return prog; 2660 } 2661 2662 struct bpf_prog *bpf_prog_get(u32 ufd) 2663 { 2664 return __bpf_prog_get(ufd, NULL, false); 2665 } 2666 2667 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2668 bool attach_drv) 2669 { 2670 return __bpf_prog_get(ufd, &type, attach_drv); 2671 } 2672 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2673 2674 /* Initially all BPF programs could be loaded w/o specifying 2675 * expected_attach_type. Later for some of them specifying expected_attach_type 2676 * at load time became required so that program could be validated properly. 2677 * Programs of types that are allowed to be loaded both w/ and w/o (for 2678 * backward compatibility) expected_attach_type, should have the default attach 2679 * type assigned to expected_attach_type for the latter case, so that it can be 2680 * validated later at attach time. 2681 * 2682 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2683 * prog type requires it but has some attach types that have to be backward 2684 * compatible. 2685 */ 2686 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2687 { 2688 switch (attr->prog_type) { 2689 case BPF_PROG_TYPE_CGROUP_SOCK: 2690 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2691 * exist so checking for non-zero is the way to go here. 2692 */ 2693 if (!attr->expected_attach_type) 2694 attr->expected_attach_type = 2695 BPF_CGROUP_INET_SOCK_CREATE; 2696 break; 2697 case BPF_PROG_TYPE_SK_REUSEPORT: 2698 if (!attr->expected_attach_type) 2699 attr->expected_attach_type = 2700 BPF_SK_REUSEPORT_SELECT; 2701 break; 2702 } 2703 } 2704 2705 static int 2706 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2707 enum bpf_attach_type expected_attach_type, 2708 struct btf *attach_btf, u32 btf_id, 2709 struct bpf_prog *dst_prog) 2710 { 2711 if (btf_id) { 2712 if (btf_id > BTF_MAX_TYPE) 2713 return -EINVAL; 2714 2715 if (!attach_btf && !dst_prog) 2716 return -EINVAL; 2717 2718 switch (prog_type) { 2719 case BPF_PROG_TYPE_TRACING: 2720 case BPF_PROG_TYPE_LSM: 2721 case BPF_PROG_TYPE_STRUCT_OPS: 2722 case BPF_PROG_TYPE_EXT: 2723 break; 2724 default: 2725 return -EINVAL; 2726 } 2727 } 2728 2729 if (attach_btf && (!btf_id || dst_prog)) 2730 return -EINVAL; 2731 2732 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2733 prog_type != BPF_PROG_TYPE_EXT) 2734 return -EINVAL; 2735 2736 switch (prog_type) { 2737 case BPF_PROG_TYPE_CGROUP_SOCK: 2738 switch (expected_attach_type) { 2739 case BPF_CGROUP_INET_SOCK_CREATE: 2740 case BPF_CGROUP_INET_SOCK_RELEASE: 2741 case BPF_CGROUP_INET4_POST_BIND: 2742 case BPF_CGROUP_INET6_POST_BIND: 2743 return 0; 2744 default: 2745 return -EINVAL; 2746 } 2747 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2748 switch (expected_attach_type) { 2749 case BPF_CGROUP_INET4_BIND: 2750 case BPF_CGROUP_INET6_BIND: 2751 case BPF_CGROUP_INET4_CONNECT: 2752 case BPF_CGROUP_INET6_CONNECT: 2753 case BPF_CGROUP_UNIX_CONNECT: 2754 case BPF_CGROUP_INET4_GETPEERNAME: 2755 case BPF_CGROUP_INET6_GETPEERNAME: 2756 case BPF_CGROUP_UNIX_GETPEERNAME: 2757 case BPF_CGROUP_INET4_GETSOCKNAME: 2758 case BPF_CGROUP_INET6_GETSOCKNAME: 2759 case BPF_CGROUP_UNIX_GETSOCKNAME: 2760 case BPF_CGROUP_UDP4_SENDMSG: 2761 case BPF_CGROUP_UDP6_SENDMSG: 2762 case BPF_CGROUP_UNIX_SENDMSG: 2763 case BPF_CGROUP_UDP4_RECVMSG: 2764 case BPF_CGROUP_UDP6_RECVMSG: 2765 case BPF_CGROUP_UNIX_RECVMSG: 2766 return 0; 2767 default: 2768 return -EINVAL; 2769 } 2770 case BPF_PROG_TYPE_CGROUP_SKB: 2771 switch (expected_attach_type) { 2772 case BPF_CGROUP_INET_INGRESS: 2773 case BPF_CGROUP_INET_EGRESS: 2774 return 0; 2775 default: 2776 return -EINVAL; 2777 } 2778 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2779 switch (expected_attach_type) { 2780 case BPF_CGROUP_SETSOCKOPT: 2781 case BPF_CGROUP_GETSOCKOPT: 2782 return 0; 2783 default: 2784 return -EINVAL; 2785 } 2786 case BPF_PROG_TYPE_SK_LOOKUP: 2787 if (expected_attach_type == BPF_SK_LOOKUP) 2788 return 0; 2789 return -EINVAL; 2790 case BPF_PROG_TYPE_SK_REUSEPORT: 2791 switch (expected_attach_type) { 2792 case BPF_SK_REUSEPORT_SELECT: 2793 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2794 return 0; 2795 default: 2796 return -EINVAL; 2797 } 2798 case BPF_PROG_TYPE_NETFILTER: 2799 if (expected_attach_type == BPF_NETFILTER) 2800 return 0; 2801 return -EINVAL; 2802 case BPF_PROG_TYPE_SYSCALL: 2803 case BPF_PROG_TYPE_EXT: 2804 if (expected_attach_type) 2805 return -EINVAL; 2806 fallthrough; 2807 default: 2808 return 0; 2809 } 2810 } 2811 2812 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2813 { 2814 switch (prog_type) { 2815 case BPF_PROG_TYPE_SCHED_CLS: 2816 case BPF_PROG_TYPE_SCHED_ACT: 2817 case BPF_PROG_TYPE_XDP: 2818 case BPF_PROG_TYPE_LWT_IN: 2819 case BPF_PROG_TYPE_LWT_OUT: 2820 case BPF_PROG_TYPE_LWT_XMIT: 2821 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2822 case BPF_PROG_TYPE_SK_SKB: 2823 case BPF_PROG_TYPE_SK_MSG: 2824 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2825 case BPF_PROG_TYPE_CGROUP_DEVICE: 2826 case BPF_PROG_TYPE_CGROUP_SOCK: 2827 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2828 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2829 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2830 case BPF_PROG_TYPE_SOCK_OPS: 2831 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2832 case BPF_PROG_TYPE_NETFILTER: 2833 return true; 2834 case BPF_PROG_TYPE_CGROUP_SKB: 2835 /* always unpriv */ 2836 case BPF_PROG_TYPE_SK_REUSEPORT: 2837 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2838 default: 2839 return false; 2840 } 2841 } 2842 2843 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2844 { 2845 switch (prog_type) { 2846 case BPF_PROG_TYPE_KPROBE: 2847 case BPF_PROG_TYPE_TRACEPOINT: 2848 case BPF_PROG_TYPE_PERF_EVENT: 2849 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2850 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2851 case BPF_PROG_TYPE_TRACING: 2852 case BPF_PROG_TYPE_LSM: 2853 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2854 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2855 return true; 2856 default: 2857 return false; 2858 } 2859 } 2860 2861 static int bpf_prog_verify_signature(struct bpf_prog *prog, union bpf_attr *attr, 2862 bool is_kernel) 2863 { 2864 bpfptr_t usig = make_bpfptr(attr->signature, is_kernel); 2865 struct bpf_dynptr_kern sig_ptr, insns_ptr; 2866 struct bpf_key *key = NULL; 2867 void *sig; 2868 int err = 0; 2869 2870 /* 2871 * Don't attempt to use kmalloc_large or vmalloc for signatures. 2872 * Practical signature for BPF program should be below this limit. 2873 */ 2874 if (attr->signature_size > KMALLOC_MAX_CACHE_SIZE) 2875 return -EINVAL; 2876 2877 if (system_keyring_id_check(attr->keyring_id) == 0) 2878 key = bpf_lookup_system_key(attr->keyring_id); 2879 else 2880 key = bpf_lookup_user_key(attr->keyring_id, 0); 2881 2882 if (!key) 2883 return -EINVAL; 2884 2885 sig = kvmemdup_bpfptr(usig, attr->signature_size); 2886 if (IS_ERR(sig)) { 2887 bpf_key_put(key); 2888 return PTR_ERR(sig); 2889 } 2890 2891 bpf_dynptr_init(&sig_ptr, sig, BPF_DYNPTR_TYPE_LOCAL, 0, 2892 attr->signature_size); 2893 bpf_dynptr_init(&insns_ptr, prog->insnsi, BPF_DYNPTR_TYPE_LOCAL, 0, 2894 prog->len * sizeof(struct bpf_insn)); 2895 2896 err = bpf_verify_pkcs7_signature((struct bpf_dynptr *)&insns_ptr, 2897 (struct bpf_dynptr *)&sig_ptr, key); 2898 2899 bpf_key_put(key); 2900 kvfree(sig); 2901 return err; 2902 } 2903 2904 static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog) 2905 { 2906 int err; 2907 int i; 2908 2909 for (i = 0; i < prog->aux->used_map_cnt; i++) { 2910 if (prog->aux->used_maps[i]->map_type != BPF_MAP_TYPE_INSN_ARRAY) 2911 continue; 2912 2913 err = bpf_insn_array_ready(prog->aux->used_maps[i]); 2914 if (err) 2915 return err; 2916 } 2917 2918 return 0; 2919 } 2920 2921 /* last field in 'union bpf_attr' used by this command */ 2922 #define BPF_PROG_LOAD_LAST_FIELD keyring_id 2923 2924 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_attr *attr_log) 2925 { 2926 enum bpf_prog_type type = attr->prog_type; 2927 struct bpf_prog *prog, *dst_prog = NULL; 2928 struct btf *attach_btf = NULL; 2929 struct bpf_token *token = NULL; 2930 bool bpf_cap; 2931 int err; 2932 char license[128]; 2933 2934 if (CHECK_ATTR(BPF_PROG_LOAD)) 2935 return -EINVAL; 2936 2937 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2938 BPF_F_ANY_ALIGNMENT | 2939 BPF_F_TEST_STATE_FREQ | 2940 BPF_F_SLEEPABLE | 2941 BPF_F_TEST_RND_HI32 | 2942 BPF_F_XDP_HAS_FRAGS | 2943 BPF_F_XDP_DEV_BOUND_ONLY | 2944 BPF_F_TEST_REG_INVARIANTS | 2945 BPF_F_TOKEN_FD)) 2946 return -EINVAL; 2947 2948 bpf_prog_load_fixup_attach_type(attr); 2949 2950 if (attr->prog_flags & BPF_F_TOKEN_FD) { 2951 token = bpf_token_get_from_fd(attr->prog_token_fd); 2952 if (IS_ERR(token)) 2953 return PTR_ERR(token); 2954 /* if current token doesn't grant prog loading permissions, 2955 * then we can't use this token, so ignore it and rely on 2956 * system-wide capabilities checks 2957 */ 2958 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || 2959 !bpf_token_allow_prog_type(token, attr->prog_type, 2960 attr->expected_attach_type)) { 2961 bpf_token_put(token); 2962 token = NULL; 2963 } 2964 } 2965 2966 bpf_cap = bpf_token_capable(token, CAP_BPF); 2967 err = -EPERM; 2968 2969 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2970 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2971 !bpf_cap) 2972 goto put_token; 2973 2974 /* Intent here is for unprivileged_bpf_disabled to block BPF program 2975 * creation for unprivileged users; other actions depend 2976 * on fd availability and access to bpffs, so are dependent on 2977 * object creation success. Even with unprivileged BPF disabled, 2978 * capability checks are still carried out for these 2979 * and other operations. 2980 */ 2981 if (sysctl_unprivileged_bpf_disabled && !bpf_cap) 2982 goto put_token; 2983 2984 if (attr->insn_cnt == 0 || 2985 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { 2986 err = -E2BIG; 2987 goto put_token; 2988 } 2989 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2990 type != BPF_PROG_TYPE_CGROUP_SKB && 2991 !bpf_cap) 2992 goto put_token; 2993 2994 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) 2995 goto put_token; 2996 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) 2997 goto put_token; 2998 2999 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 3000 * or btf, we need to check which one it is 3001 */ 3002 if (attr->attach_prog_fd) { 3003 dst_prog = bpf_prog_get(attr->attach_prog_fd); 3004 if (IS_ERR(dst_prog)) { 3005 dst_prog = NULL; 3006 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 3007 if (IS_ERR(attach_btf)) { 3008 err = -EINVAL; 3009 goto put_token; 3010 } 3011 if (!btf_is_kernel(attach_btf)) { 3012 /* attaching through specifying bpf_prog's BTF 3013 * objects directly might be supported eventually 3014 */ 3015 btf_put(attach_btf); 3016 err = -ENOTSUPP; 3017 goto put_token; 3018 } 3019 } 3020 } else if (attr->attach_btf_id) { 3021 /* fall back to vmlinux BTF, if BTF type ID is specified */ 3022 attach_btf = bpf_get_btf_vmlinux(); 3023 if (IS_ERR(attach_btf)) { 3024 err = PTR_ERR(attach_btf); 3025 goto put_token; 3026 } 3027 if (!attach_btf) { 3028 err = -EINVAL; 3029 goto put_token; 3030 } 3031 btf_get(attach_btf); 3032 } 3033 3034 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 3035 attach_btf, attr->attach_btf_id, 3036 dst_prog)) { 3037 if (dst_prog) 3038 bpf_prog_put(dst_prog); 3039 if (attach_btf) 3040 btf_put(attach_btf); 3041 err = -EINVAL; 3042 goto put_token; 3043 } 3044 3045 /* plain bpf_prog allocation */ 3046 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 3047 if (!prog) { 3048 if (dst_prog) 3049 bpf_prog_put(dst_prog); 3050 if (attach_btf) 3051 btf_put(attach_btf); 3052 err = -EINVAL; 3053 goto put_token; 3054 } 3055 3056 prog->expected_attach_type = attr->expected_attach_type; 3057 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); 3058 prog->aux->attach_btf = attach_btf; 3059 prog->aux->attach_btf_id = attr->attach_btf_id; 3060 prog->aux->dst_prog = dst_prog; 3061 prog->aux->dev_bound = !!attr->prog_ifindex; 3062 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 3063 3064 /* move token into prog->aux, reuse taken refcnt */ 3065 prog->aux->token = token; 3066 token = NULL; 3067 3068 prog->aux->user = get_current_user(); 3069 prog->len = attr->insn_cnt; 3070 3071 err = -EFAULT; 3072 if (copy_from_bpfptr(prog->insns, 3073 make_bpfptr(attr->insns, uattr.is_kernel), 3074 bpf_prog_insn_size(prog)) != 0) 3075 goto free_prog; 3076 /* copy eBPF program license from user space */ 3077 if (strncpy_from_bpfptr(license, 3078 make_bpfptr(attr->license, uattr.is_kernel), 3079 sizeof(license) - 1) < 0) 3080 goto free_prog; 3081 license[sizeof(license) - 1] = 0; 3082 3083 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 3084 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; 3085 3086 if (attr->signature) { 3087 err = bpf_prog_verify_signature(prog, attr, uattr.is_kernel); 3088 if (err) 3089 goto free_prog; 3090 } 3091 3092 prog->orig_prog = NULL; 3093 prog->jited = 0; 3094 3095 atomic64_set(&prog->aux->refcnt, 1); 3096 3097 if (bpf_prog_is_dev_bound(prog->aux)) { 3098 err = bpf_prog_dev_bound_init(prog, attr); 3099 if (err) 3100 goto free_prog; 3101 } 3102 3103 if (type == BPF_PROG_TYPE_EXT && dst_prog && 3104 bpf_prog_is_dev_bound(dst_prog->aux)) { 3105 err = bpf_prog_dev_bound_inherit(prog, dst_prog); 3106 if (err) 3107 goto free_prog; 3108 } 3109 3110 /* 3111 * Bookkeeping for managing the program attachment chain. 3112 * 3113 * It might be tempting to set attach_tracing_prog flag at the attachment 3114 * time, but this will not prevent from loading bunch of tracing prog 3115 * first, then attach them one to another. 3116 * 3117 * The flag attach_tracing_prog is set for the whole program lifecycle, and 3118 * doesn't have to be cleared in bpf_tracing_link_release, since tracing 3119 * programs cannot change attachment target. 3120 */ 3121 if (type == BPF_PROG_TYPE_TRACING && dst_prog && 3122 dst_prog->type == BPF_PROG_TYPE_TRACING) { 3123 prog->aux->attach_tracing_prog = true; 3124 } 3125 3126 /* find program type: socket_filter vs tracing_filter */ 3127 err = find_prog_type(type, prog); 3128 if (err < 0) 3129 goto free_prog; 3130 3131 prog->aux->load_time = ktime_get_boottime_ns(); 3132 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 3133 sizeof(attr->prog_name)); 3134 if (err < 0) 3135 goto free_prog; 3136 3137 err = security_bpf_prog_load(prog, attr, token, uattr.is_kernel); 3138 if (err) 3139 goto free_prog_sec; 3140 3141 /* run eBPF verifier */ 3142 err = bpf_check(&prog, attr, uattr, attr_log); 3143 if (err < 0) 3144 goto free_used_maps; 3145 3146 err = bpf_prog_mark_insn_arrays_ready(prog); 3147 if (err < 0) 3148 goto free_used_maps; 3149 3150 err = bpf_prog_alloc_id(prog); 3151 if (err) 3152 goto free_used_maps; 3153 3154 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 3155 * effectively publicly exposed. However, retrieving via 3156 * bpf_prog_get_fd_by_id() will take another reference, 3157 * therefore it cannot be gone underneath us. 3158 * 3159 * Only for the time /after/ successful bpf_prog_new_fd() 3160 * and before returning to userspace, we might just hold 3161 * one reference and any parallel close on that fd could 3162 * rip everything out. Hence, below notifications must 3163 * happen before bpf_prog_new_fd(). 3164 * 3165 * Also, any failure handling from this point onwards must 3166 * be using bpf_prog_put() given the program is exposed. 3167 */ 3168 bpf_prog_kallsyms_add(prog); 3169 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 3170 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 3171 3172 err = bpf_prog_new_fd(prog); 3173 if (err < 0) 3174 bpf_prog_put(prog); 3175 return err; 3176 3177 free_used_maps: 3178 /* In case we have subprogs, we need to wait for a grace 3179 * period before we can tear down JIT memory since symbols 3180 * are already exposed under kallsyms. 3181 */ 3182 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); 3183 return err; 3184 3185 free_prog_sec: 3186 security_bpf_prog_free(prog); 3187 free_prog: 3188 free_uid(prog->aux->user); 3189 if (prog->aux->attach_btf) 3190 btf_put(prog->aux->attach_btf); 3191 bpf_prog_free(prog); 3192 put_token: 3193 bpf_token_put(token); 3194 return err; 3195 } 3196 3197 #define BPF_OBJ_LAST_FIELD path_fd 3198 3199 static int bpf_obj_pin(const union bpf_attr *attr) 3200 { 3201 int path_fd; 3202 3203 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) 3204 return -EINVAL; 3205 3206 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3207 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3208 return -EINVAL; 3209 3210 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3211 return bpf_obj_pin_user(attr->bpf_fd, path_fd, 3212 u64_to_user_ptr(attr->pathname)); 3213 } 3214 3215 static int bpf_obj_get(const union bpf_attr *attr) 3216 { 3217 int path_fd; 3218 3219 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 3220 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) 3221 return -EINVAL; 3222 3223 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3224 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3225 return -EINVAL; 3226 3227 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3228 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), 3229 attr->file_flags); 3230 } 3231 3232 /* bpf_link_init_sleepable() allows to specify whether BPF link itself has 3233 * "sleepable" semantics, which normally would mean that BPF link's attach 3234 * hook can dereference link or link's underlying program for some time after 3235 * detachment due to RCU Tasks Trace-based lifetime protection scheme. 3236 * BPF program itself can be non-sleepable, yet, because it's transitively 3237 * reachable through BPF link, its freeing has to be delayed until after RCU 3238 * Tasks Trace GP. 3239 */ 3240 void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type, 3241 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3242 enum bpf_attach_type attach_type, bool sleepable) 3243 { 3244 WARN_ON(ops->dealloc && ops->dealloc_deferred); 3245 atomic64_set(&link->refcnt, 1); 3246 link->type = type; 3247 link->sleepable = sleepable; 3248 link->id = 0; 3249 link->ops = ops; 3250 link->prog = prog; 3251 link->attach_type = attach_type; 3252 } 3253 3254 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 3255 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3256 enum bpf_attach_type attach_type) 3257 { 3258 bpf_link_init_sleepable(link, type, ops, prog, attach_type, false); 3259 } 3260 3261 static void bpf_link_free_id(int id) 3262 { 3263 if (!id) 3264 return; 3265 3266 spin_lock_bh(&link_idr_lock); 3267 idr_remove(&link_idr, id); 3268 spin_unlock_bh(&link_idr_lock); 3269 } 3270 3271 /* Clean up bpf_link and corresponding anon_inode file and FD. After 3272 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 3273 * anon_inode's release() call. This helper marks bpf_link as 3274 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 3275 * is not decremented, it's the responsibility of a calling code that failed 3276 * to complete bpf_link initialization. 3277 * This helper eventually calls link's dealloc callback, but does not call 3278 * link's release callback. 3279 */ 3280 void bpf_link_cleanup(struct bpf_link_primer *primer) 3281 { 3282 primer->link->prog = NULL; 3283 bpf_link_free_id(primer->id); 3284 fput(primer->file); 3285 put_unused_fd(primer->fd); 3286 } 3287 3288 void bpf_link_inc(struct bpf_link *link) 3289 { 3290 atomic64_inc(&link->refcnt); 3291 } 3292 3293 static void bpf_link_dealloc(struct bpf_link *link) 3294 { 3295 /* now that we know that bpf_link itself can't be reached, put underlying BPF program */ 3296 if (link->prog) 3297 bpf_prog_put(link->prog); 3298 3299 /* free bpf_link and its containing memory */ 3300 if (link->ops->dealloc_deferred) 3301 link->ops->dealloc_deferred(link); 3302 else 3303 link->ops->dealloc(link); 3304 } 3305 3306 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) 3307 { 3308 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); 3309 3310 bpf_link_dealloc(link); 3311 } 3312 3313 static bool bpf_link_is_tracepoint(struct bpf_link *link) 3314 { 3315 /* 3316 * Only these combinations support a tracepoint bpf_link. 3317 * BPF_LINK_TYPE_TRACING raw_tp progs are hardcoded to use 3318 * bpf_raw_tp_link_lops and thus dealloc_deferred(), see 3319 * bpf_raw_tp_link_attach(). 3320 */ 3321 return link->type == BPF_LINK_TYPE_RAW_TRACEPOINT || 3322 (link->type == BPF_LINK_TYPE_TRACING && link->attach_type == BPF_TRACE_RAW_TP); 3323 } 3324 3325 /* bpf_link_free is guaranteed to be called from process context */ 3326 static void bpf_link_free(struct bpf_link *link) 3327 { 3328 const struct bpf_link_ops *ops = link->ops; 3329 3330 bpf_link_free_id(link->id); 3331 /* detach BPF program, clean up used resources */ 3332 if (link->prog) 3333 ops->release(link); 3334 if (ops->dealloc_deferred) { 3335 /* 3336 * Schedule BPF link deallocation, which will only then 3337 * trigger putting BPF program refcount. 3338 * If underlying BPF program is sleepable or BPF link's target 3339 * attach hookpoint is sleepable or otherwise requires RCU GPs 3340 * to ensure link and its underlying BPF program is not 3341 * reachable anymore, we need to first wait for RCU tasks 3342 * trace sync, and then go through "classic" RCU grace period. 3343 * 3344 * For tracepoint BPF links, we need to go through SRCU grace 3345 * period wait instead when non-faultable tracepoint is used. We 3346 * don't need to chain SRCU grace period waits, however, for the 3347 * faultable case, since it exclusively uses RCU Tasks Trace. 3348 */ 3349 if (link->sleepable || (link->prog && link->prog->sleepable)) 3350 /* RCU Tasks Trace grace period implies RCU grace period. */ 3351 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3352 /* We need to do a SRCU grace period wait for non-faultable tracepoint BPF links. */ 3353 else if (bpf_link_is_tracepoint(link)) 3354 call_tracepoint_unregister_atomic(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3355 else 3356 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3357 } else if (ops->dealloc) { 3358 bpf_link_dealloc(link); 3359 } 3360 } 3361 3362 static void bpf_link_put_deferred(struct work_struct *work) 3363 { 3364 struct bpf_link *link = container_of(work, struct bpf_link, work); 3365 3366 bpf_link_free(link); 3367 } 3368 3369 /* bpf_link_put might be called from atomic context. It needs to be called 3370 * from sleepable context in order to acquire sleeping locks during the process. 3371 */ 3372 void bpf_link_put(struct bpf_link *link) 3373 { 3374 if (!atomic64_dec_and_test(&link->refcnt)) 3375 return; 3376 3377 INIT_WORK(&link->work, bpf_link_put_deferred); 3378 schedule_work(&link->work); 3379 } 3380 EXPORT_SYMBOL(bpf_link_put); 3381 3382 static void bpf_link_put_direct(struct bpf_link *link) 3383 { 3384 if (!atomic64_dec_and_test(&link->refcnt)) 3385 return; 3386 bpf_link_free(link); 3387 } 3388 3389 static int bpf_link_release(struct inode *inode, struct file *filp) 3390 { 3391 struct bpf_link *link = filp->private_data; 3392 3393 bpf_link_put_direct(link); 3394 return 0; 3395 } 3396 3397 #ifdef CONFIG_PROC_FS 3398 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 3399 #define BPF_MAP_TYPE(_id, _ops) 3400 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 3401 static const char *bpf_link_type_strs[] = { 3402 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 3403 #include <linux/bpf_types.h> 3404 }; 3405 #undef BPF_PROG_TYPE 3406 #undef BPF_MAP_TYPE 3407 #undef BPF_LINK_TYPE 3408 3409 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 3410 { 3411 const struct bpf_link *link = filp->private_data; 3412 const struct bpf_prog *prog = link->prog; 3413 enum bpf_link_type type = link->type; 3414 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 3415 3416 if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) { 3417 if (link->type == BPF_LINK_TYPE_KPROBE_MULTI) 3418 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_KPROBE_MULTI_RETURN ? 3419 "kretprobe_multi" : "kprobe_multi"); 3420 else if (link->type == BPF_LINK_TYPE_UPROBE_MULTI) 3421 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_UPROBE_MULTI_RETURN ? 3422 "uretprobe_multi" : "uprobe_multi"); 3423 else 3424 seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]); 3425 } else { 3426 WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type); 3427 seq_printf(m, "link_type:\t<%u>\n", type); 3428 } 3429 seq_printf(m, "link_id:\t%u\n", link->id); 3430 3431 if (prog) { 3432 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 3433 seq_printf(m, 3434 "prog_tag:\t%s\n" 3435 "prog_id:\t%u\n", 3436 prog_tag, 3437 prog->aux->id); 3438 } 3439 if (link->ops->show_fdinfo) 3440 link->ops->show_fdinfo(link, m); 3441 } 3442 #endif 3443 3444 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts) 3445 { 3446 struct bpf_link *link = file->private_data; 3447 3448 return link->ops->poll(file, pts); 3449 } 3450 3451 static const struct file_operations bpf_link_fops = { 3452 #ifdef CONFIG_PROC_FS 3453 .show_fdinfo = bpf_link_show_fdinfo, 3454 #endif 3455 .release = bpf_link_release, 3456 .read = bpf_dummy_read, 3457 .write = bpf_dummy_write, 3458 }; 3459 3460 static const struct file_operations bpf_link_fops_poll = { 3461 #ifdef CONFIG_PROC_FS 3462 .show_fdinfo = bpf_link_show_fdinfo, 3463 #endif 3464 .release = bpf_link_release, 3465 .read = bpf_dummy_read, 3466 .write = bpf_dummy_write, 3467 .poll = bpf_link_poll, 3468 }; 3469 3470 static int bpf_link_alloc_id(struct bpf_link *link) 3471 { 3472 int id; 3473 3474 idr_preload(GFP_KERNEL); 3475 spin_lock_bh(&link_idr_lock); 3476 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 3477 spin_unlock_bh(&link_idr_lock); 3478 idr_preload_end(); 3479 3480 return id; 3481 } 3482 3483 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 3484 * reserving unused FD and allocating ID from link_idr. This is to be paired 3485 * with bpf_link_settle() to install FD and ID and expose bpf_link to 3486 * user-space, if bpf_link is successfully attached. If not, bpf_link and 3487 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 3488 * transient state is passed around in struct bpf_link_primer. 3489 * This is preferred way to create and initialize bpf_link, especially when 3490 * there are complicated and expensive operations in between creating bpf_link 3491 * itself and attaching it to BPF hook. By using bpf_link_prime() and 3492 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 3493 * expensive (and potentially failing) roll back operations in a rare case 3494 * that file, FD, or ID can't be allocated. 3495 */ 3496 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 3497 { 3498 struct file *file; 3499 int fd, id; 3500 3501 fd = get_unused_fd_flags(O_CLOEXEC); 3502 if (fd < 0) 3503 return fd; 3504 3505 3506 id = bpf_link_alloc_id(link); 3507 if (id < 0) { 3508 put_unused_fd(fd); 3509 return id; 3510 } 3511 3512 file = anon_inode_getfile("bpf_link", 3513 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3514 link, O_CLOEXEC); 3515 if (IS_ERR(file)) { 3516 bpf_link_free_id(id); 3517 put_unused_fd(fd); 3518 return PTR_ERR(file); 3519 } 3520 3521 primer->link = link; 3522 primer->file = file; 3523 primer->fd = fd; 3524 primer->id = id; 3525 return 0; 3526 } 3527 3528 int bpf_link_settle(struct bpf_link_primer *primer) 3529 { 3530 /* make bpf_link fetchable by ID */ 3531 spin_lock_bh(&link_idr_lock); 3532 primer->link->id = primer->id; 3533 spin_unlock_bh(&link_idr_lock); 3534 /* make bpf_link fetchable by FD */ 3535 fd_install(primer->fd, primer->file); 3536 /* pass through installed FD */ 3537 return primer->fd; 3538 } 3539 3540 int bpf_link_new_fd(struct bpf_link *link) 3541 { 3542 return anon_inode_getfd("bpf-link", 3543 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3544 link, O_CLOEXEC); 3545 } 3546 3547 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 3548 { 3549 CLASS(fd, f)(ufd); 3550 struct bpf_link *link; 3551 3552 if (fd_empty(f)) 3553 return ERR_PTR(-EBADF); 3554 if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll) 3555 return ERR_PTR(-EINVAL); 3556 3557 link = fd_file(f)->private_data; 3558 bpf_link_inc(link); 3559 return link; 3560 } 3561 EXPORT_SYMBOL_NS(bpf_link_get_from_fd, "BPF_INTERNAL"); 3562 3563 static void bpf_tracing_link_release(struct bpf_link *link) 3564 { 3565 struct bpf_tracing_link *tr_link = 3566 container_of(link, struct bpf_tracing_link, link.link); 3567 3568 WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, 3569 tr_link->trampoline, 3570 tr_link->tgt_prog)); 3571 3572 bpf_trampoline_put(tr_link->trampoline); 3573 3574 /* tgt_prog is NULL if target is a kernel function */ 3575 if (tr_link->tgt_prog) 3576 bpf_prog_put(tr_link->tgt_prog); 3577 } 3578 3579 static void bpf_tracing_link_dealloc(struct bpf_link *link) 3580 { 3581 struct bpf_tracing_link *tr_link = 3582 container_of(link, struct bpf_tracing_link, link.link); 3583 3584 kfree(tr_link); 3585 } 3586 3587 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 3588 struct seq_file *seq) 3589 { 3590 struct bpf_tracing_link *tr_link = 3591 container_of(link, struct bpf_tracing_link, link.link); 3592 u32 target_btf_id, target_obj_id; 3593 3594 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3595 &target_obj_id, &target_btf_id); 3596 seq_printf(seq, 3597 "attach_type:\t%d\n" 3598 "target_obj_id:\t%u\n" 3599 "target_btf_id:\t%u\n" 3600 "cookie:\t%llu\n", 3601 link->attach_type, 3602 target_obj_id, 3603 target_btf_id, 3604 tr_link->link.cookie); 3605 } 3606 3607 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 3608 struct bpf_link_info *info) 3609 { 3610 struct bpf_tracing_link *tr_link = 3611 container_of(link, struct bpf_tracing_link, link.link); 3612 3613 info->tracing.attach_type = link->attach_type; 3614 info->tracing.cookie = tr_link->link.cookie; 3615 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3616 &info->tracing.target_obj_id, 3617 &info->tracing.target_btf_id); 3618 3619 return 0; 3620 } 3621 3622 static const struct bpf_link_ops bpf_tracing_link_lops = { 3623 .release = bpf_tracing_link_release, 3624 .dealloc = bpf_tracing_link_dealloc, 3625 .show_fdinfo = bpf_tracing_link_show_fdinfo, 3626 .fill_link_info = bpf_tracing_link_fill_link_info, 3627 }; 3628 3629 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 3630 int tgt_prog_fd, 3631 u32 btf_id, 3632 u64 bpf_cookie, 3633 enum bpf_attach_type attach_type) 3634 { 3635 struct bpf_link_primer link_primer; 3636 struct bpf_prog *tgt_prog = NULL; 3637 struct bpf_trampoline *tr = NULL; 3638 struct bpf_tracing_link *link; 3639 u64 key = 0; 3640 int err; 3641 3642 switch (prog->type) { 3643 case BPF_PROG_TYPE_TRACING: 3644 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 3645 prog->expected_attach_type != BPF_TRACE_FEXIT && 3646 prog->expected_attach_type != BPF_TRACE_FSESSION && 3647 prog->expected_attach_type != BPF_MODIFY_RETURN) { 3648 err = -EINVAL; 3649 goto out_put_prog; 3650 } 3651 break; 3652 case BPF_PROG_TYPE_EXT: 3653 if (prog->expected_attach_type != 0) { 3654 err = -EINVAL; 3655 goto out_put_prog; 3656 } 3657 break; 3658 case BPF_PROG_TYPE_LSM: 3659 if (prog->expected_attach_type != BPF_LSM_MAC) { 3660 err = -EINVAL; 3661 goto out_put_prog; 3662 } 3663 break; 3664 default: 3665 err = -EINVAL; 3666 goto out_put_prog; 3667 } 3668 3669 if (!!tgt_prog_fd != !!btf_id) { 3670 err = -EINVAL; 3671 goto out_put_prog; 3672 } 3673 3674 if (tgt_prog_fd) { 3675 /* 3676 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this 3677 * part would be changed to implement the same for 3678 * BPF_PROG_TYPE_TRACING, do not forget to update the way how 3679 * attach_tracing_prog flag is set. 3680 */ 3681 if (prog->type != BPF_PROG_TYPE_EXT) { 3682 err = -EINVAL; 3683 goto out_put_prog; 3684 } 3685 3686 tgt_prog = bpf_prog_get(tgt_prog_fd); 3687 if (IS_ERR(tgt_prog)) { 3688 err = PTR_ERR(tgt_prog); 3689 tgt_prog = NULL; 3690 goto out_put_prog; 3691 } 3692 3693 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 3694 } 3695 3696 if (prog->expected_attach_type == BPF_TRACE_FSESSION) { 3697 struct bpf_fsession_link *fslink; 3698 3699 fslink = kzalloc_obj(*fslink, GFP_USER); 3700 if (fslink) { 3701 bpf_link_init(&fslink->fexit.link, BPF_LINK_TYPE_TRACING, 3702 &bpf_tracing_link_lops, prog, attach_type); 3703 fslink->fexit.cookie = bpf_cookie; 3704 link = &fslink->link; 3705 } else { 3706 link = NULL; 3707 } 3708 } else { 3709 link = kzalloc_obj(*link, GFP_USER); 3710 } 3711 if (!link) { 3712 err = -ENOMEM; 3713 goto out_put_prog; 3714 } 3715 bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, 3716 &bpf_tracing_link_lops, prog, attach_type); 3717 3718 link->link.cookie = bpf_cookie; 3719 3720 mutex_lock(&prog->aux->dst_mutex); 3721 3722 /* There are a few possible cases here: 3723 * 3724 * - if prog->aux->dst_trampoline is set, the program was just loaded 3725 * and not yet attached to anything, so we can use the values stored 3726 * in prog->aux 3727 * 3728 * - if prog->aux->dst_trampoline is NULL, the program has already been 3729 * attached to a target and its initial target was cleared (below) 3730 * 3731 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 3732 * target_btf_id using the link_create API. 3733 * 3734 * - if tgt_prog == NULL when this function was called using the old 3735 * raw_tracepoint_open API, and we need a target from prog->aux 3736 * 3737 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 3738 * was detached and is going for re-attachment. 3739 * 3740 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf 3741 * are NULL, then program was already attached and user did not provide 3742 * tgt_prog_fd so we have no way to find out or create trampoline 3743 */ 3744 if (!prog->aux->dst_trampoline && !tgt_prog) { 3745 /* 3746 * Allow re-attach for TRACING and LSM programs. If it's 3747 * currently linked, bpf_trampoline_link_prog will fail. 3748 * EXT programs need to specify tgt_prog_fd, so they 3749 * re-attach in separate code path. 3750 */ 3751 if (prog->type != BPF_PROG_TYPE_TRACING && 3752 prog->type != BPF_PROG_TYPE_LSM) { 3753 err = -EINVAL; 3754 goto out_unlock; 3755 } 3756 /* We can allow re-attach only if we have valid attach_btf. */ 3757 if (!prog->aux->attach_btf) { 3758 err = -EINVAL; 3759 goto out_unlock; 3760 } 3761 btf_id = prog->aux->attach_btf_id; 3762 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 3763 } 3764 3765 if (!prog->aux->dst_trampoline || 3766 (key && key != prog->aux->dst_trampoline->key)) { 3767 /* If there is no saved target, or the specified target is 3768 * different from the destination specified at load time, we 3769 * need a new trampoline and a check for compatibility 3770 */ 3771 struct bpf_attach_target_info tgt_info = {}; 3772 3773 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 3774 &tgt_info); 3775 if (err) 3776 goto out_unlock; 3777 3778 if (tgt_info.tgt_mod) { 3779 module_put(prog->aux->mod); 3780 prog->aux->mod = tgt_info.tgt_mod; 3781 } 3782 3783 tr = bpf_trampoline_get(key, &tgt_info); 3784 if (!tr) { 3785 err = -ENOMEM; 3786 goto out_unlock; 3787 } 3788 } else { 3789 /* The caller didn't specify a target, or the target was the 3790 * same as the destination supplied during program load. This 3791 * means we can reuse the trampoline and reference from program 3792 * load time, and there is no need to allocate a new one. This 3793 * can only happen once for any program, as the saved values in 3794 * prog->aux are cleared below. 3795 */ 3796 tr = prog->aux->dst_trampoline; 3797 tgt_prog = prog->aux->dst_prog; 3798 } 3799 /* 3800 * It is to prevent modifying struct pt_regs via kprobe_write_ctx=true 3801 * freplace prog. Without this check, kprobe_write_ctx=true freplace 3802 * prog is allowed to attach to kprobe_write_ctx=false kprobe prog, and 3803 * then modify the registers of the kprobe prog's target kernel 3804 * function. 3805 * 3806 * This also blocks the combination of uprobe+freplace, because it is 3807 * unable to recognize the use of the tgt_prog as an uprobe or a kprobe 3808 * by tgt_prog itself. At attach time, uprobe/kprobe is recognized by 3809 * the target perf event flags in __perf_event_set_bpf_prog(). 3810 */ 3811 if (prog->type == BPF_PROG_TYPE_EXT && 3812 prog->aux->kprobe_write_ctx != tgt_prog->aux->kprobe_write_ctx) { 3813 err = -EINVAL; 3814 goto out_unlock; 3815 } 3816 3817 err = bpf_link_prime(&link->link.link, &link_primer); 3818 if (err) 3819 goto out_unlock; 3820 3821 err = bpf_trampoline_link_prog(&link->link, tr, tgt_prog); 3822 if (err) { 3823 bpf_link_cleanup(&link_primer); 3824 link = NULL; 3825 goto out_unlock; 3826 } 3827 3828 link->tgt_prog = tgt_prog; 3829 link->trampoline = tr; 3830 3831 /* Always clear the trampoline and target prog from prog->aux to make 3832 * sure the original attach destination is not kept alive after a 3833 * program is (re-)attached to another target. 3834 */ 3835 if (prog->aux->dst_prog && 3836 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 3837 /* got extra prog ref from syscall, or attaching to different prog */ 3838 bpf_prog_put(prog->aux->dst_prog); 3839 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 3840 /* we allocated a new trampoline, so free the old one */ 3841 bpf_trampoline_put(prog->aux->dst_trampoline); 3842 3843 prog->aux->dst_prog = NULL; 3844 prog->aux->dst_trampoline = NULL; 3845 mutex_unlock(&prog->aux->dst_mutex); 3846 3847 return bpf_link_settle(&link_primer); 3848 out_unlock: 3849 if (tr && tr != prog->aux->dst_trampoline) 3850 bpf_trampoline_put(tr); 3851 mutex_unlock(&prog->aux->dst_mutex); 3852 kfree(link); 3853 out_put_prog: 3854 if (tgt_prog_fd && tgt_prog) 3855 bpf_prog_put(tgt_prog); 3856 return err; 3857 } 3858 3859 static void bpf_raw_tp_link_release(struct bpf_link *link) 3860 { 3861 struct bpf_raw_tp_link *raw_tp = 3862 container_of(link, struct bpf_raw_tp_link, link); 3863 3864 bpf_probe_unregister(raw_tp->btp, raw_tp); 3865 bpf_put_raw_tracepoint(raw_tp->btp); 3866 } 3867 3868 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 3869 { 3870 struct bpf_raw_tp_link *raw_tp = 3871 container_of(link, struct bpf_raw_tp_link, link); 3872 3873 kfree(raw_tp); 3874 } 3875 3876 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 3877 struct seq_file *seq) 3878 { 3879 struct bpf_raw_tp_link *raw_tp_link = 3880 container_of(link, struct bpf_raw_tp_link, link); 3881 3882 seq_printf(seq, 3883 "tp_name:\t%s\n" 3884 "cookie:\t%llu\n", 3885 raw_tp_link->btp->tp->name, 3886 raw_tp_link->cookie); 3887 } 3888 3889 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, 3890 u32 len) 3891 { 3892 if (ulen >= len + 1) { 3893 if (copy_to_user(ubuf, buf, len + 1)) 3894 return -EFAULT; 3895 } else { 3896 char zero = '\0'; 3897 3898 if (copy_to_user(ubuf, buf, ulen - 1)) 3899 return -EFAULT; 3900 if (put_user(zero, ubuf + ulen - 1)) 3901 return -EFAULT; 3902 return -ENOSPC; 3903 } 3904 3905 return 0; 3906 } 3907 3908 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 3909 struct bpf_link_info *info) 3910 { 3911 struct bpf_raw_tp_link *raw_tp_link = 3912 container_of(link, struct bpf_raw_tp_link, link); 3913 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 3914 const char *tp_name = raw_tp_link->btp->tp->name; 3915 u32 ulen = info->raw_tracepoint.tp_name_len; 3916 size_t tp_len = strlen(tp_name); 3917 3918 if (!ulen ^ !ubuf) 3919 return -EINVAL; 3920 3921 info->raw_tracepoint.tp_name_len = tp_len + 1; 3922 info->raw_tracepoint.cookie = raw_tp_link->cookie; 3923 3924 if (!ubuf) 3925 return 0; 3926 3927 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); 3928 } 3929 3930 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 3931 .release = bpf_raw_tp_link_release, 3932 .dealloc_deferred = bpf_raw_tp_link_dealloc, 3933 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 3934 .fill_link_info = bpf_raw_tp_link_fill_link_info, 3935 }; 3936 3937 #ifdef CONFIG_PERF_EVENTS 3938 struct bpf_perf_link { 3939 struct bpf_link link; 3940 struct file *perf_file; 3941 }; 3942 3943 static void bpf_perf_link_release(struct bpf_link *link) 3944 { 3945 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3946 struct perf_event *event = perf_link->perf_file->private_data; 3947 3948 perf_event_free_bpf_prog(event); 3949 fput(perf_link->perf_file); 3950 } 3951 3952 static void bpf_perf_link_dealloc(struct bpf_link *link) 3953 { 3954 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3955 3956 kfree(perf_link); 3957 } 3958 3959 static int bpf_perf_link_fill_common(const struct perf_event *event, 3960 char __user *uname, u32 *ulenp, 3961 u64 *probe_offset, u64 *probe_addr, 3962 u32 *fd_type, unsigned long *missed) 3963 { 3964 const char *buf; 3965 u32 prog_id, ulen; 3966 size_t len; 3967 int err; 3968 3969 ulen = *ulenp; 3970 if (!ulen ^ !uname) 3971 return -EINVAL; 3972 3973 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, 3974 probe_offset, probe_addr, missed); 3975 if (err) 3976 return err; 3977 3978 if (buf) { 3979 len = strlen(buf); 3980 *ulenp = len + 1; 3981 } else { 3982 *ulenp = 1; 3983 } 3984 if (!uname) 3985 return 0; 3986 3987 if (buf) { 3988 err = bpf_copy_to_user(uname, buf, ulen, len); 3989 if (err) 3990 return err; 3991 } else { 3992 char zero = '\0'; 3993 3994 if (put_user(zero, uname)) 3995 return -EFAULT; 3996 } 3997 return 0; 3998 } 3999 4000 #ifdef CONFIG_KPROBE_EVENTS 4001 static int bpf_perf_link_fill_kprobe(const struct perf_event *event, 4002 struct bpf_link_info *info) 4003 { 4004 unsigned long missed; 4005 char __user *uname; 4006 u64 addr, offset; 4007 u32 ulen, type; 4008 int err; 4009 4010 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); 4011 ulen = info->perf_event.kprobe.name_len; 4012 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr, 4013 &type, &missed); 4014 if (err) 4015 return err; 4016 if (type == BPF_FD_TYPE_KRETPROBE) 4017 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; 4018 else 4019 info->perf_event.type = BPF_PERF_EVENT_KPROBE; 4020 info->perf_event.kprobe.name_len = ulen; 4021 info->perf_event.kprobe.offset = offset; 4022 info->perf_event.kprobe.missed = missed; 4023 if (!kallsyms_show_value(current_cred())) 4024 addr = 0; 4025 info->perf_event.kprobe.addr = addr; 4026 info->perf_event.kprobe.cookie = event->bpf_cookie; 4027 return 0; 4028 } 4029 4030 static void bpf_perf_link_fdinfo_kprobe(const struct perf_event *event, 4031 struct seq_file *seq) 4032 { 4033 const char *name; 4034 int err; 4035 u32 prog_id, type; 4036 u64 offset, addr; 4037 unsigned long missed; 4038 4039 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 4040 &offset, &addr, &missed); 4041 if (err) 4042 return; 4043 4044 seq_printf(seq, 4045 "name:\t%s\n" 4046 "offset:\t%#llx\n" 4047 "missed:\t%lu\n" 4048 "addr:\t%#llx\n" 4049 "event_type:\t%s\n" 4050 "cookie:\t%llu\n", 4051 name, offset, missed, addr, 4052 type == BPF_FD_TYPE_KRETPROBE ? "kretprobe" : "kprobe", 4053 event->bpf_cookie); 4054 } 4055 #endif 4056 4057 #ifdef CONFIG_UPROBE_EVENTS 4058 static int bpf_perf_link_fill_uprobe(const struct perf_event *event, 4059 struct bpf_link_info *info) 4060 { 4061 u64 ref_ctr_offset, offset; 4062 char __user *uname; 4063 u32 ulen, type; 4064 int err; 4065 4066 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); 4067 ulen = info->perf_event.uprobe.name_len; 4068 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &ref_ctr_offset, 4069 &type, NULL); 4070 if (err) 4071 return err; 4072 4073 if (type == BPF_FD_TYPE_URETPROBE) 4074 info->perf_event.type = BPF_PERF_EVENT_URETPROBE; 4075 else 4076 info->perf_event.type = BPF_PERF_EVENT_UPROBE; 4077 info->perf_event.uprobe.name_len = ulen; 4078 info->perf_event.uprobe.offset = offset; 4079 info->perf_event.uprobe.cookie = event->bpf_cookie; 4080 info->perf_event.uprobe.ref_ctr_offset = ref_ctr_offset; 4081 return 0; 4082 } 4083 4084 static void bpf_perf_link_fdinfo_uprobe(const struct perf_event *event, 4085 struct seq_file *seq) 4086 { 4087 const char *name; 4088 int err; 4089 u32 prog_id, type; 4090 u64 offset, ref_ctr_offset; 4091 unsigned long missed; 4092 4093 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 4094 &offset, &ref_ctr_offset, &missed); 4095 if (err) 4096 return; 4097 4098 seq_printf(seq, 4099 "name:\t%s\n" 4100 "offset:\t%#llx\n" 4101 "ref_ctr_offset:\t%#llx\n" 4102 "event_type:\t%s\n" 4103 "cookie:\t%llu\n", 4104 name, offset, ref_ctr_offset, 4105 type == BPF_FD_TYPE_URETPROBE ? "uretprobe" : "uprobe", 4106 event->bpf_cookie); 4107 } 4108 #endif 4109 4110 static int bpf_perf_link_fill_probe(const struct perf_event *event, 4111 struct bpf_link_info *info) 4112 { 4113 #ifdef CONFIG_KPROBE_EVENTS 4114 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 4115 return bpf_perf_link_fill_kprobe(event, info); 4116 #endif 4117 #ifdef CONFIG_UPROBE_EVENTS 4118 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 4119 return bpf_perf_link_fill_uprobe(event, info); 4120 #endif 4121 return -EOPNOTSUPP; 4122 } 4123 4124 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, 4125 struct bpf_link_info *info) 4126 { 4127 char __user *uname; 4128 u32 ulen; 4129 int err; 4130 4131 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); 4132 ulen = info->perf_event.tracepoint.name_len; 4133 err = bpf_perf_link_fill_common(event, uname, &ulen, NULL, NULL, NULL, NULL); 4134 if (err) 4135 return err; 4136 4137 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; 4138 info->perf_event.tracepoint.name_len = ulen; 4139 info->perf_event.tracepoint.cookie = event->bpf_cookie; 4140 return 0; 4141 } 4142 4143 static int bpf_perf_link_fill_perf_event(const struct perf_event *event, 4144 struct bpf_link_info *info) 4145 { 4146 info->perf_event.event.type = event->attr.type; 4147 info->perf_event.event.config = event->attr.config; 4148 info->perf_event.event.cookie = event->bpf_cookie; 4149 info->perf_event.type = BPF_PERF_EVENT_EVENT; 4150 return 0; 4151 } 4152 4153 static int bpf_perf_link_fill_link_info(const struct bpf_link *link, 4154 struct bpf_link_info *info) 4155 { 4156 struct bpf_perf_link *perf_link; 4157 const struct perf_event *event; 4158 4159 perf_link = container_of(link, struct bpf_perf_link, link); 4160 event = perf_get_event(perf_link->perf_file); 4161 if (IS_ERR(event)) 4162 return PTR_ERR(event); 4163 4164 switch (event->prog->type) { 4165 case BPF_PROG_TYPE_PERF_EVENT: 4166 return bpf_perf_link_fill_perf_event(event, info); 4167 case BPF_PROG_TYPE_TRACEPOINT: 4168 return bpf_perf_link_fill_tracepoint(event, info); 4169 case BPF_PROG_TYPE_KPROBE: 4170 return bpf_perf_link_fill_probe(event, info); 4171 default: 4172 return -EOPNOTSUPP; 4173 } 4174 } 4175 4176 static void bpf_perf_event_link_show_fdinfo(const struct perf_event *event, 4177 struct seq_file *seq) 4178 { 4179 seq_printf(seq, 4180 "type:\t%u\n" 4181 "config:\t%llu\n" 4182 "event_type:\t%s\n" 4183 "cookie:\t%llu\n", 4184 event->attr.type, event->attr.config, 4185 "event", event->bpf_cookie); 4186 } 4187 4188 static void bpf_tracepoint_link_show_fdinfo(const struct perf_event *event, 4189 struct seq_file *seq) 4190 { 4191 int err; 4192 const char *name; 4193 u32 prog_id; 4194 4195 err = bpf_get_perf_event_info(event, &prog_id, NULL, &name, NULL, 4196 NULL, NULL); 4197 if (err) 4198 return; 4199 4200 seq_printf(seq, 4201 "tp_name:\t%s\n" 4202 "event_type:\t%s\n" 4203 "cookie:\t%llu\n", 4204 name, "tracepoint", event->bpf_cookie); 4205 } 4206 4207 static void bpf_probe_link_show_fdinfo(const struct perf_event *event, 4208 struct seq_file *seq) 4209 { 4210 #ifdef CONFIG_KPROBE_EVENTS 4211 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 4212 return bpf_perf_link_fdinfo_kprobe(event, seq); 4213 #endif 4214 4215 #ifdef CONFIG_UPROBE_EVENTS 4216 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 4217 return bpf_perf_link_fdinfo_uprobe(event, seq); 4218 #endif 4219 } 4220 4221 static void bpf_perf_link_show_fdinfo(const struct bpf_link *link, 4222 struct seq_file *seq) 4223 { 4224 struct bpf_perf_link *perf_link; 4225 const struct perf_event *event; 4226 4227 perf_link = container_of(link, struct bpf_perf_link, link); 4228 event = perf_get_event(perf_link->perf_file); 4229 if (IS_ERR(event)) 4230 return; 4231 4232 switch (event->prog->type) { 4233 case BPF_PROG_TYPE_PERF_EVENT: 4234 return bpf_perf_event_link_show_fdinfo(event, seq); 4235 case BPF_PROG_TYPE_TRACEPOINT: 4236 return bpf_tracepoint_link_show_fdinfo(event, seq); 4237 case BPF_PROG_TYPE_KPROBE: 4238 return bpf_probe_link_show_fdinfo(event, seq); 4239 default: 4240 return; 4241 } 4242 } 4243 4244 static const struct bpf_link_ops bpf_perf_link_lops = { 4245 .release = bpf_perf_link_release, 4246 .dealloc = bpf_perf_link_dealloc, 4247 .fill_link_info = bpf_perf_link_fill_link_info, 4248 .show_fdinfo = bpf_perf_link_show_fdinfo, 4249 }; 4250 4251 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4252 { 4253 struct bpf_link_primer link_primer; 4254 struct bpf_perf_link *link; 4255 struct perf_event *event; 4256 struct file *perf_file; 4257 int err; 4258 4259 if (attr->link_create.flags) 4260 return -EINVAL; 4261 4262 perf_file = perf_event_get(attr->link_create.target_fd); 4263 if (IS_ERR(perf_file)) 4264 return PTR_ERR(perf_file); 4265 4266 link = kzalloc_obj(*link, GFP_USER); 4267 if (!link) { 4268 err = -ENOMEM; 4269 goto out_put_file; 4270 } 4271 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog, 4272 attr->link_create.attach_type); 4273 link->perf_file = perf_file; 4274 4275 err = bpf_link_prime(&link->link, &link_primer); 4276 if (err) { 4277 kfree(link); 4278 goto out_put_file; 4279 } 4280 4281 event = perf_file->private_data; 4282 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 4283 if (err) { 4284 bpf_link_cleanup(&link_primer); 4285 goto out_put_file; 4286 } 4287 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 4288 bpf_prog_inc(prog); 4289 4290 return bpf_link_settle(&link_primer); 4291 4292 out_put_file: 4293 fput(perf_file); 4294 return err; 4295 } 4296 #else 4297 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4298 { 4299 return -EOPNOTSUPP; 4300 } 4301 #endif /* CONFIG_PERF_EVENTS */ 4302 4303 static int bpf_raw_tp_link_attach(struct bpf_prog *prog, 4304 const char __user *user_tp_name, u64 cookie, 4305 enum bpf_attach_type attach_type) 4306 { 4307 struct bpf_link_primer link_primer; 4308 struct bpf_raw_tp_link *link; 4309 struct bpf_raw_event_map *btp; 4310 const char *tp_name; 4311 char buf[128]; 4312 int err; 4313 4314 switch (prog->type) { 4315 case BPF_PROG_TYPE_TRACING: 4316 case BPF_PROG_TYPE_EXT: 4317 case BPF_PROG_TYPE_LSM: 4318 if (user_tp_name) 4319 /* The attach point for this category of programs 4320 * should be specified via btf_id during program load. 4321 */ 4322 return -EINVAL; 4323 if (prog->type == BPF_PROG_TYPE_TRACING && 4324 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 4325 tp_name = prog->aux->attach_func_name; 4326 break; 4327 } 4328 return bpf_tracing_prog_attach(prog, 0, 0, 0, attach_type); 4329 case BPF_PROG_TYPE_RAW_TRACEPOINT: 4330 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 4331 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) 4332 return -EFAULT; 4333 buf[sizeof(buf) - 1] = 0; 4334 tp_name = buf; 4335 break; 4336 default: 4337 return -EINVAL; 4338 } 4339 4340 btp = bpf_get_raw_tracepoint(tp_name); 4341 if (!btp) 4342 return -ENOENT; 4343 4344 if (prog->sleepable && !tracepoint_is_faultable(btp->tp)) { 4345 bpf_put_raw_tracepoint(btp); 4346 return -EINVAL; 4347 } 4348 4349 link = kzalloc_obj(*link, GFP_USER); 4350 if (!link) { 4351 err = -ENOMEM; 4352 goto out_put_btp; 4353 } 4354 bpf_link_init_sleepable(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 4355 &bpf_raw_tp_link_lops, prog, attach_type, 4356 tracepoint_is_faultable(btp->tp)); 4357 link->btp = btp; 4358 link->cookie = cookie; 4359 4360 err = bpf_link_prime(&link->link, &link_primer); 4361 if (err) { 4362 kfree(link); 4363 goto out_put_btp; 4364 } 4365 4366 err = bpf_probe_register(link->btp, link); 4367 if (err) { 4368 bpf_link_cleanup(&link_primer); 4369 goto out_put_btp; 4370 } 4371 4372 return bpf_link_settle(&link_primer); 4373 4374 out_put_btp: 4375 bpf_put_raw_tracepoint(btp); 4376 return err; 4377 } 4378 4379 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie 4380 4381 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 4382 { 4383 struct bpf_prog *prog; 4384 void __user *tp_name; 4385 __u64 cookie; 4386 int fd; 4387 4388 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 4389 return -EINVAL; 4390 4391 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 4392 if (IS_ERR(prog)) 4393 return PTR_ERR(prog); 4394 4395 tp_name = u64_to_user_ptr(attr->raw_tracepoint.name); 4396 cookie = attr->raw_tracepoint.cookie; 4397 fd = bpf_raw_tp_link_attach(prog, tp_name, cookie, prog->expected_attach_type); 4398 if (fd < 0) 4399 bpf_prog_put(prog); 4400 return fd; 4401 } 4402 4403 static enum bpf_prog_type 4404 attach_type_to_prog_type(enum bpf_attach_type attach_type) 4405 { 4406 switch (attach_type) { 4407 case BPF_CGROUP_INET_INGRESS: 4408 case BPF_CGROUP_INET_EGRESS: 4409 return BPF_PROG_TYPE_CGROUP_SKB; 4410 case BPF_CGROUP_INET_SOCK_CREATE: 4411 case BPF_CGROUP_INET_SOCK_RELEASE: 4412 case BPF_CGROUP_INET4_POST_BIND: 4413 case BPF_CGROUP_INET6_POST_BIND: 4414 return BPF_PROG_TYPE_CGROUP_SOCK; 4415 case BPF_CGROUP_INET4_BIND: 4416 case BPF_CGROUP_INET6_BIND: 4417 case BPF_CGROUP_INET4_CONNECT: 4418 case BPF_CGROUP_INET6_CONNECT: 4419 case BPF_CGROUP_UNIX_CONNECT: 4420 case BPF_CGROUP_INET4_GETPEERNAME: 4421 case BPF_CGROUP_INET6_GETPEERNAME: 4422 case BPF_CGROUP_UNIX_GETPEERNAME: 4423 case BPF_CGROUP_INET4_GETSOCKNAME: 4424 case BPF_CGROUP_INET6_GETSOCKNAME: 4425 case BPF_CGROUP_UNIX_GETSOCKNAME: 4426 case BPF_CGROUP_UDP4_SENDMSG: 4427 case BPF_CGROUP_UDP6_SENDMSG: 4428 case BPF_CGROUP_UNIX_SENDMSG: 4429 case BPF_CGROUP_UDP4_RECVMSG: 4430 case BPF_CGROUP_UDP6_RECVMSG: 4431 case BPF_CGROUP_UNIX_RECVMSG: 4432 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 4433 case BPF_CGROUP_SOCK_OPS: 4434 return BPF_PROG_TYPE_SOCK_OPS; 4435 case BPF_CGROUP_DEVICE: 4436 return BPF_PROG_TYPE_CGROUP_DEVICE; 4437 case BPF_SK_MSG_VERDICT: 4438 return BPF_PROG_TYPE_SK_MSG; 4439 case BPF_SK_SKB_STREAM_PARSER: 4440 case BPF_SK_SKB_STREAM_VERDICT: 4441 case BPF_SK_SKB_VERDICT: 4442 return BPF_PROG_TYPE_SK_SKB; 4443 case BPF_LIRC_MODE2: 4444 return BPF_PROG_TYPE_LIRC_MODE2; 4445 case BPF_FLOW_DISSECTOR: 4446 return BPF_PROG_TYPE_FLOW_DISSECTOR; 4447 case BPF_CGROUP_SYSCTL: 4448 return BPF_PROG_TYPE_CGROUP_SYSCTL; 4449 case BPF_CGROUP_GETSOCKOPT: 4450 case BPF_CGROUP_SETSOCKOPT: 4451 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 4452 case BPF_TRACE_ITER: 4453 case BPF_TRACE_RAW_TP: 4454 case BPF_TRACE_FENTRY: 4455 case BPF_TRACE_FEXIT: 4456 case BPF_TRACE_FSESSION: 4457 case BPF_MODIFY_RETURN: 4458 return BPF_PROG_TYPE_TRACING; 4459 case BPF_LSM_MAC: 4460 return BPF_PROG_TYPE_LSM; 4461 case BPF_SK_LOOKUP: 4462 return BPF_PROG_TYPE_SK_LOOKUP; 4463 case BPF_XDP: 4464 return BPF_PROG_TYPE_XDP; 4465 case BPF_LSM_CGROUP: 4466 return BPF_PROG_TYPE_LSM; 4467 case BPF_TCX_INGRESS: 4468 case BPF_TCX_EGRESS: 4469 case BPF_NETKIT_PRIMARY: 4470 case BPF_NETKIT_PEER: 4471 return BPF_PROG_TYPE_SCHED_CLS; 4472 default: 4473 return BPF_PROG_TYPE_UNSPEC; 4474 } 4475 } 4476 4477 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 4478 enum bpf_attach_type attach_type) 4479 { 4480 enum bpf_prog_type ptype; 4481 4482 switch (prog->type) { 4483 case BPF_PROG_TYPE_CGROUP_SOCK: 4484 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4485 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4486 case BPF_PROG_TYPE_SK_LOOKUP: 4487 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 4488 case BPF_PROG_TYPE_CGROUP_SKB: 4489 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) 4490 /* cg-skb progs can be loaded by unpriv user. 4491 * check permissions at attach time. 4492 */ 4493 return -EPERM; 4494 4495 ptype = attach_type_to_prog_type(attach_type); 4496 if (prog->type != ptype) 4497 return -EINVAL; 4498 4499 return prog->enforce_expected_attach_type && 4500 prog->expected_attach_type != attach_type ? 4501 -EINVAL : 0; 4502 case BPF_PROG_TYPE_EXT: 4503 return 0; 4504 case BPF_PROG_TYPE_NETFILTER: 4505 if (attach_type != BPF_NETFILTER) 4506 return -EINVAL; 4507 return 0; 4508 case BPF_PROG_TYPE_PERF_EVENT: 4509 case BPF_PROG_TYPE_TRACEPOINT: 4510 if (attach_type != BPF_PERF_EVENT) 4511 return -EINVAL; 4512 return 0; 4513 case BPF_PROG_TYPE_KPROBE: 4514 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && 4515 attach_type != BPF_TRACE_KPROBE_MULTI) 4516 return -EINVAL; 4517 if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION && 4518 attach_type != BPF_TRACE_KPROBE_SESSION) 4519 return -EINVAL; 4520 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && 4521 attach_type != BPF_TRACE_UPROBE_MULTI) 4522 return -EINVAL; 4523 if (prog->expected_attach_type == BPF_TRACE_UPROBE_SESSION && 4524 attach_type != BPF_TRACE_UPROBE_SESSION) 4525 return -EINVAL; 4526 if (attach_type != BPF_PERF_EVENT && 4527 attach_type != BPF_TRACE_KPROBE_MULTI && 4528 attach_type != BPF_TRACE_KPROBE_SESSION && 4529 attach_type != BPF_TRACE_UPROBE_MULTI && 4530 attach_type != BPF_TRACE_UPROBE_SESSION) 4531 return -EINVAL; 4532 return 0; 4533 case BPF_PROG_TYPE_SCHED_CLS: 4534 if (attach_type != BPF_TCX_INGRESS && 4535 attach_type != BPF_TCX_EGRESS && 4536 attach_type != BPF_NETKIT_PRIMARY && 4537 attach_type != BPF_NETKIT_PEER) 4538 return -EINVAL; 4539 return 0; 4540 default: 4541 ptype = attach_type_to_prog_type(attach_type); 4542 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) 4543 return -EINVAL; 4544 return 0; 4545 } 4546 } 4547 4548 static bool is_cgroup_prog_type(enum bpf_prog_type ptype, enum bpf_attach_type atype, 4549 bool check_atype) 4550 { 4551 switch (ptype) { 4552 case BPF_PROG_TYPE_CGROUP_DEVICE: 4553 case BPF_PROG_TYPE_CGROUP_SKB: 4554 case BPF_PROG_TYPE_CGROUP_SOCK: 4555 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4556 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4557 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4558 case BPF_PROG_TYPE_SOCK_OPS: 4559 return true; 4560 case BPF_PROG_TYPE_LSM: 4561 return check_atype ? atype == BPF_LSM_CGROUP : true; 4562 default: 4563 return false; 4564 } 4565 } 4566 4567 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision 4568 4569 #define BPF_F_ATTACH_MASK_BASE \ 4570 (BPF_F_ALLOW_OVERRIDE | \ 4571 BPF_F_ALLOW_MULTI | \ 4572 BPF_F_REPLACE | \ 4573 BPF_F_PREORDER) 4574 4575 #define BPF_F_ATTACH_MASK_MPROG \ 4576 (BPF_F_REPLACE | \ 4577 BPF_F_BEFORE | \ 4578 BPF_F_AFTER | \ 4579 BPF_F_ID | \ 4580 BPF_F_LINK) 4581 4582 static int bpf_prog_attach(const union bpf_attr *attr) 4583 { 4584 enum bpf_prog_type ptype; 4585 struct bpf_prog *prog; 4586 int ret; 4587 4588 if (CHECK_ATTR(BPF_PROG_ATTACH)) 4589 return -EINVAL; 4590 4591 ptype = attach_type_to_prog_type(attr->attach_type); 4592 if (ptype == BPF_PROG_TYPE_UNSPEC) 4593 return -EINVAL; 4594 if (bpf_mprog_supported(ptype)) { 4595 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4596 return -EINVAL; 4597 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4598 if (attr->attach_flags & ~(BPF_F_ATTACH_MASK_BASE | BPF_F_ATTACH_MASK_MPROG)) 4599 return -EINVAL; 4600 } else { 4601 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) 4602 return -EINVAL; 4603 if (attr->relative_fd || 4604 attr->expected_revision) 4605 return -EINVAL; 4606 } 4607 4608 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4609 if (IS_ERR(prog)) 4610 return PTR_ERR(prog); 4611 4612 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 4613 bpf_prog_put(prog); 4614 return -EINVAL; 4615 } 4616 4617 if (is_cgroup_prog_type(ptype, prog->expected_attach_type, true)) { 4618 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 4619 goto out; 4620 } 4621 4622 switch (ptype) { 4623 case BPF_PROG_TYPE_SK_SKB: 4624 case BPF_PROG_TYPE_SK_MSG: 4625 ret = sock_map_get_from_fd(attr, prog); 4626 break; 4627 case BPF_PROG_TYPE_LIRC_MODE2: 4628 ret = lirc_prog_attach(attr, prog); 4629 break; 4630 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4631 ret = netns_bpf_prog_attach(attr, prog); 4632 break; 4633 case BPF_PROG_TYPE_SCHED_CLS: 4634 if (attr->attach_type == BPF_TCX_INGRESS || 4635 attr->attach_type == BPF_TCX_EGRESS) 4636 ret = tcx_prog_attach(attr, prog); 4637 else 4638 ret = netkit_prog_attach(attr, prog); 4639 break; 4640 default: 4641 ret = -EINVAL; 4642 } 4643 out: 4644 if (ret) 4645 bpf_prog_put(prog); 4646 return ret; 4647 } 4648 4649 #define BPF_PROG_DETACH_LAST_FIELD expected_revision 4650 4651 static int bpf_prog_detach(const union bpf_attr *attr) 4652 { 4653 struct bpf_prog *prog = NULL; 4654 enum bpf_prog_type ptype; 4655 int ret; 4656 4657 if (CHECK_ATTR(BPF_PROG_DETACH)) 4658 return -EINVAL; 4659 4660 ptype = attach_type_to_prog_type(attr->attach_type); 4661 if (bpf_mprog_supported(ptype)) { 4662 if (ptype == BPF_PROG_TYPE_UNSPEC) 4663 return -EINVAL; 4664 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4665 return -EINVAL; 4666 if (attr->attach_bpf_fd) { 4667 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4668 if (IS_ERR(prog)) 4669 return PTR_ERR(prog); 4670 } else if (!bpf_mprog_detach_empty(ptype)) { 4671 return -EPERM; 4672 } 4673 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4674 if (attr->attach_flags || attr->relative_fd) 4675 return -EINVAL; 4676 } else if (attr->attach_flags || 4677 attr->relative_fd || 4678 attr->expected_revision) { 4679 return -EINVAL; 4680 } 4681 4682 switch (ptype) { 4683 case BPF_PROG_TYPE_SK_MSG: 4684 case BPF_PROG_TYPE_SK_SKB: 4685 ret = sock_map_prog_detach(attr, ptype); 4686 break; 4687 case BPF_PROG_TYPE_LIRC_MODE2: 4688 ret = lirc_prog_detach(attr); 4689 break; 4690 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4691 ret = netns_bpf_prog_detach(attr, ptype); 4692 break; 4693 case BPF_PROG_TYPE_CGROUP_DEVICE: 4694 case BPF_PROG_TYPE_CGROUP_SKB: 4695 case BPF_PROG_TYPE_CGROUP_SOCK: 4696 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4697 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4698 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4699 case BPF_PROG_TYPE_SOCK_OPS: 4700 case BPF_PROG_TYPE_LSM: 4701 ret = cgroup_bpf_prog_detach(attr, ptype); 4702 break; 4703 case BPF_PROG_TYPE_SCHED_CLS: 4704 if (attr->attach_type == BPF_TCX_INGRESS || 4705 attr->attach_type == BPF_TCX_EGRESS) 4706 ret = tcx_prog_detach(attr, prog); 4707 else 4708 ret = netkit_prog_detach(attr, prog); 4709 break; 4710 default: 4711 ret = -EINVAL; 4712 } 4713 4714 if (prog) 4715 bpf_prog_put(prog); 4716 return ret; 4717 } 4718 4719 #define BPF_PROG_QUERY_LAST_FIELD query.revision 4720 4721 static int bpf_prog_query(const union bpf_attr *attr, 4722 union bpf_attr __user *uattr, u32 uattr_size) 4723 { 4724 if (!bpf_net_capable()) 4725 return -EPERM; 4726 if (CHECK_ATTR(BPF_PROG_QUERY)) 4727 return -EINVAL; 4728 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 4729 return -EINVAL; 4730 4731 switch (attr->query.attach_type) { 4732 case BPF_CGROUP_INET_INGRESS: 4733 case BPF_CGROUP_INET_EGRESS: 4734 case BPF_CGROUP_INET_SOCK_CREATE: 4735 case BPF_CGROUP_INET_SOCK_RELEASE: 4736 case BPF_CGROUP_INET4_BIND: 4737 case BPF_CGROUP_INET6_BIND: 4738 case BPF_CGROUP_INET4_POST_BIND: 4739 case BPF_CGROUP_INET6_POST_BIND: 4740 case BPF_CGROUP_INET4_CONNECT: 4741 case BPF_CGROUP_INET6_CONNECT: 4742 case BPF_CGROUP_UNIX_CONNECT: 4743 case BPF_CGROUP_INET4_GETPEERNAME: 4744 case BPF_CGROUP_INET6_GETPEERNAME: 4745 case BPF_CGROUP_UNIX_GETPEERNAME: 4746 case BPF_CGROUP_INET4_GETSOCKNAME: 4747 case BPF_CGROUP_INET6_GETSOCKNAME: 4748 case BPF_CGROUP_UNIX_GETSOCKNAME: 4749 case BPF_CGROUP_UDP4_SENDMSG: 4750 case BPF_CGROUP_UDP6_SENDMSG: 4751 case BPF_CGROUP_UNIX_SENDMSG: 4752 case BPF_CGROUP_UDP4_RECVMSG: 4753 case BPF_CGROUP_UDP6_RECVMSG: 4754 case BPF_CGROUP_UNIX_RECVMSG: 4755 case BPF_CGROUP_SOCK_OPS: 4756 case BPF_CGROUP_DEVICE: 4757 case BPF_CGROUP_SYSCTL: 4758 case BPF_CGROUP_GETSOCKOPT: 4759 case BPF_CGROUP_SETSOCKOPT: 4760 case BPF_LSM_CGROUP: 4761 return cgroup_bpf_prog_query(attr, uattr, uattr_size); 4762 case BPF_LIRC_MODE2: 4763 return lirc_prog_query(attr, uattr); 4764 case BPF_FLOW_DISSECTOR: 4765 case BPF_SK_LOOKUP: 4766 return netns_bpf_prog_query(attr, uattr); 4767 case BPF_SK_SKB_STREAM_PARSER: 4768 case BPF_SK_SKB_STREAM_VERDICT: 4769 case BPF_SK_MSG_VERDICT: 4770 case BPF_SK_SKB_VERDICT: 4771 return sock_map_bpf_prog_query(attr, uattr); 4772 case BPF_TCX_INGRESS: 4773 case BPF_TCX_EGRESS: 4774 return tcx_prog_query(attr, uattr); 4775 case BPF_NETKIT_PRIMARY: 4776 case BPF_NETKIT_PEER: 4777 return netkit_prog_query(attr, uattr); 4778 default: 4779 return -EINVAL; 4780 } 4781 } 4782 4783 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size 4784 4785 static int bpf_prog_test_run(const union bpf_attr *attr, 4786 union bpf_attr __user *uattr) 4787 { 4788 struct bpf_prog *prog; 4789 int ret = -ENOTSUPP; 4790 4791 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 4792 return -EINVAL; 4793 4794 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 4795 (!attr->test.ctx_size_in && attr->test.ctx_in)) 4796 return -EINVAL; 4797 4798 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 4799 (!attr->test.ctx_size_out && attr->test.ctx_out)) 4800 return -EINVAL; 4801 4802 prog = bpf_prog_get(attr->test.prog_fd); 4803 if (IS_ERR(prog)) 4804 return PTR_ERR(prog); 4805 4806 if (prog->aux->ops->test_run) 4807 ret = prog->aux->ops->test_run(prog, attr, uattr); 4808 4809 bpf_prog_put(prog); 4810 return ret; 4811 } 4812 4813 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 4814 4815 static int bpf_obj_get_next_id(const union bpf_attr *attr, 4816 union bpf_attr __user *uattr, 4817 struct idr *idr, 4818 spinlock_t *lock) 4819 { 4820 u32 next_id = attr->start_id; 4821 int err = 0; 4822 4823 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 4824 return -EINVAL; 4825 4826 if (!capable(CAP_SYS_ADMIN)) 4827 return -EPERM; 4828 4829 next_id++; 4830 spin_lock_bh(lock); 4831 if (!idr_get_next(idr, &next_id)) 4832 err = -ENOENT; 4833 spin_unlock_bh(lock); 4834 4835 if (!err) 4836 err = put_user(next_id, &uattr->next_id); 4837 4838 return err; 4839 } 4840 4841 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 4842 { 4843 struct bpf_map *map; 4844 4845 spin_lock_bh(&map_idr_lock); 4846 again: 4847 map = idr_get_next(&map_idr, id); 4848 if (map) { 4849 map = __bpf_map_inc_not_zero(map, false); 4850 if (IS_ERR(map)) { 4851 (*id)++; 4852 goto again; 4853 } 4854 } 4855 spin_unlock_bh(&map_idr_lock); 4856 4857 return map; 4858 } 4859 4860 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 4861 { 4862 struct bpf_prog *prog; 4863 4864 spin_lock_bh(&prog_idr_lock); 4865 again: 4866 prog = idr_get_next(&prog_idr, id); 4867 if (prog) { 4868 prog = bpf_prog_inc_not_zero(prog); 4869 if (IS_ERR(prog)) { 4870 (*id)++; 4871 goto again; 4872 } 4873 } 4874 spin_unlock_bh(&prog_idr_lock); 4875 4876 return prog; 4877 } 4878 4879 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 4880 4881 struct bpf_prog *bpf_prog_by_id(u32 id) 4882 { 4883 struct bpf_prog *prog; 4884 4885 if (!id) 4886 return ERR_PTR(-ENOENT); 4887 4888 spin_lock_bh(&prog_idr_lock); 4889 prog = idr_find(&prog_idr, id); 4890 if (prog) 4891 prog = bpf_prog_inc_not_zero(prog); 4892 else 4893 prog = ERR_PTR(-ENOENT); 4894 spin_unlock_bh(&prog_idr_lock); 4895 return prog; 4896 } 4897 4898 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 4899 { 4900 struct bpf_prog *prog; 4901 u32 id = attr->prog_id; 4902 int fd; 4903 4904 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 4905 return -EINVAL; 4906 4907 if (!capable(CAP_SYS_ADMIN)) 4908 return -EPERM; 4909 4910 prog = bpf_prog_by_id(id); 4911 if (IS_ERR(prog)) 4912 return PTR_ERR(prog); 4913 4914 fd = bpf_prog_new_fd(prog); 4915 if (fd < 0) 4916 bpf_prog_put(prog); 4917 4918 return fd; 4919 } 4920 4921 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 4922 4923 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 4924 { 4925 struct bpf_map *map; 4926 u32 id = attr->map_id; 4927 int f_flags; 4928 int fd; 4929 4930 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 4931 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 4932 return -EINVAL; 4933 4934 if (!capable(CAP_SYS_ADMIN)) 4935 return -EPERM; 4936 4937 f_flags = bpf_get_file_flag(attr->open_flags); 4938 if (f_flags < 0) 4939 return f_flags; 4940 4941 spin_lock_bh(&map_idr_lock); 4942 map = idr_find(&map_idr, id); 4943 if (map) 4944 map = __bpf_map_inc_not_zero(map, true); 4945 else 4946 map = ERR_PTR(-ENOENT); 4947 spin_unlock_bh(&map_idr_lock); 4948 4949 if (IS_ERR(map)) 4950 return PTR_ERR(map); 4951 4952 fd = bpf_map_new_fd(map, f_flags); 4953 if (fd < 0) 4954 bpf_map_put_with_uref(map); 4955 4956 return fd; 4957 } 4958 4959 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 4960 unsigned long addr, u32 *off, 4961 u32 *type) 4962 { 4963 const struct bpf_map *map; 4964 int i; 4965 4966 mutex_lock(&prog->aux->used_maps_mutex); 4967 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 4968 map = prog->aux->used_maps[i]; 4969 if (map == (void *)addr) { 4970 *type = BPF_PSEUDO_MAP_FD; 4971 goto out; 4972 } 4973 if (!map->ops->map_direct_value_meta) 4974 continue; 4975 if (!map->ops->map_direct_value_meta(map, addr, off)) { 4976 *type = BPF_PSEUDO_MAP_VALUE; 4977 goto out; 4978 } 4979 } 4980 map = NULL; 4981 4982 out: 4983 mutex_unlock(&prog->aux->used_maps_mutex); 4984 return map; 4985 } 4986 4987 static void prepare_dump_pseudo_call(struct bpf_insn *insn) 4988 { 4989 s32 call_off = insn->imm; 4990 4991 /* 4992 * BPF_CALL_ARGS only exists for interpreter fallback. 4993 * 1. For interpreter (BPF_CALL_ARGS): insn->off is the index of 4994 * interpreters_args array, so here using bpf_call_args_imm() 4995 * to get the real address offset. 4996 * 2. For JIT (BPF_CALL): insn->off is the subprog id. 4997 */ 4998 if (insn->code == (BPF_JMP | BPF_CALL_ARGS)) 4999 insn->imm = bpf_call_args_imm(insn->off); 5000 else 5001 insn->imm = insn->off; 5002 5003 /* Avoid dumping a truncated and misleading pc-relative offset. */ 5004 if (call_off > S16_MAX || call_off < S16_MIN) 5005 insn->off = 0; 5006 else 5007 insn->off = call_off; 5008 } 5009 5010 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 5011 const struct cred *f_cred) 5012 { 5013 const struct bpf_map *map; 5014 struct bpf_insn *insns; 5015 u32 off, type; 5016 u64 imm; 5017 u8 code; 5018 int i; 5019 5020 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 5021 GFP_USER); 5022 if (!insns) 5023 return insns; 5024 5025 for (i = 0; i < prog->len; i++) { 5026 code = insns[i].code; 5027 5028 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 5029 insns[i].code = BPF_JMP | BPF_CALL; 5030 insns[i].imm = BPF_FUNC_tail_call; 5031 /* fall-through */ 5032 } 5033 if (code == (BPF_JMP | BPF_CALL) || 5034 code == (BPF_JMP | BPF_CALL_ARGS)) { 5035 /* Restore the legacy xlated dump layout. */ 5036 if (insns[i].src_reg == BPF_PSEUDO_CALL) 5037 prepare_dump_pseudo_call(&insns[i]); 5038 if (code == (BPF_JMP | BPF_CALL_ARGS)) 5039 insns[i].code = BPF_JMP | BPF_CALL; 5040 if (!bpf_dump_raw_ok(f_cred)) 5041 insns[i].imm = 0; 5042 continue; 5043 } 5044 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 5045 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 5046 continue; 5047 } 5048 5049 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || 5050 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { 5051 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; 5052 continue; 5053 } 5054 5055 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 5056 continue; 5057 5058 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 5059 map = bpf_map_from_imm(prog, imm, &off, &type); 5060 if (map) { 5061 insns[i].src_reg = type; 5062 insns[i].imm = map->id; 5063 insns[i + 1].imm = off; 5064 continue; 5065 } 5066 } 5067 5068 return insns; 5069 } 5070 5071 static int set_info_rec_size(struct bpf_prog_info *info) 5072 { 5073 /* 5074 * Ensure info.*_rec_size is the same as kernel expected size 5075 * 5076 * or 5077 * 5078 * Only allow zero *_rec_size if both _rec_size and _cnt are 5079 * zero. In this case, the kernel will set the expected 5080 * _rec_size back to the info. 5081 */ 5082 5083 if ((info->nr_func_info || info->func_info_rec_size) && 5084 info->func_info_rec_size != sizeof(struct bpf_func_info)) 5085 return -EINVAL; 5086 5087 if ((info->nr_line_info || info->line_info_rec_size) && 5088 info->line_info_rec_size != sizeof(struct bpf_line_info)) 5089 return -EINVAL; 5090 5091 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 5092 info->jited_line_info_rec_size != sizeof(__u64)) 5093 return -EINVAL; 5094 5095 info->func_info_rec_size = sizeof(struct bpf_func_info); 5096 info->line_info_rec_size = sizeof(struct bpf_line_info); 5097 info->jited_line_info_rec_size = sizeof(__u64); 5098 5099 return 0; 5100 } 5101 5102 static int bpf_prog_get_info_by_fd(struct file *file, 5103 struct bpf_prog *prog, 5104 const union bpf_attr *attr, 5105 union bpf_attr __user *uattr) 5106 { 5107 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5108 struct btf *attach_btf = bpf_prog_get_target_btf(prog); 5109 struct bpf_prog_info info; 5110 u32 info_len = attr->info.info_len; 5111 struct bpf_prog_kstats stats; 5112 char __user *uinsns; 5113 u32 ulen; 5114 int err; 5115 5116 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5117 if (err) 5118 return err; 5119 info_len = min_t(u32, sizeof(info), info_len); 5120 5121 memset(&info, 0, sizeof(info)); 5122 if (copy_from_user(&info, uinfo, info_len)) 5123 return -EFAULT; 5124 5125 info.type = prog->type; 5126 info.id = prog->aux->id; 5127 info.load_time = prog->aux->load_time; 5128 info.created_by_uid = from_kuid_munged(current_user_ns(), 5129 prog->aux->user->uid); 5130 info.gpl_compatible = prog->gpl_compatible; 5131 5132 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 5133 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 5134 5135 mutex_lock(&prog->aux->used_maps_mutex); 5136 ulen = info.nr_map_ids; 5137 info.nr_map_ids = prog->aux->used_map_cnt; 5138 ulen = min_t(u32, info.nr_map_ids, ulen); 5139 if (ulen) { 5140 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 5141 u32 i; 5142 5143 for (i = 0; i < ulen; i++) 5144 if (put_user(prog->aux->used_maps[i]->id, 5145 &user_map_ids[i])) { 5146 mutex_unlock(&prog->aux->used_maps_mutex); 5147 return -EFAULT; 5148 } 5149 } 5150 mutex_unlock(&prog->aux->used_maps_mutex); 5151 5152 err = set_info_rec_size(&info); 5153 if (err) 5154 return err; 5155 5156 bpf_prog_get_stats(prog, &stats); 5157 info.run_time_ns = stats.nsecs; 5158 info.run_cnt = stats.cnt; 5159 info.recursion_misses = stats.misses; 5160 5161 info.verified_insns = prog->aux->verified_insns; 5162 if (prog->aux->btf) 5163 info.btf_id = btf_obj_id(prog->aux->btf); 5164 5165 if (!bpf_capable()) { 5166 info.jited_prog_len = 0; 5167 info.xlated_prog_len = 0; 5168 info.nr_jited_ksyms = 0; 5169 info.nr_jited_func_lens = 0; 5170 info.nr_func_info = 0; 5171 info.nr_line_info = 0; 5172 info.nr_jited_line_info = 0; 5173 goto done; 5174 } 5175 5176 ulen = info.xlated_prog_len; 5177 info.xlated_prog_len = bpf_prog_insn_size(prog); 5178 if (info.xlated_prog_len && ulen) { 5179 struct bpf_insn *insns_sanitized; 5180 bool fault; 5181 5182 if (!prog->blinded || bpf_dump_raw_ok(file->f_cred)) { 5183 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 5184 if (!insns_sanitized) 5185 return -ENOMEM; 5186 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 5187 ulen = min_t(u32, info.xlated_prog_len, ulen); 5188 fault = copy_to_user(uinsns, insns_sanitized, ulen); 5189 kfree(insns_sanitized); 5190 if (fault) 5191 return -EFAULT; 5192 } else { 5193 info.xlated_prog_insns = 0; 5194 } 5195 } 5196 5197 if (bpf_prog_is_offloaded(prog->aux)) { 5198 err = bpf_prog_offload_info_fill(&info, prog); 5199 if (err) 5200 return err; 5201 goto done; 5202 } 5203 5204 /* NOTE: the following code is supposed to be skipped for offload. 5205 * bpf_prog_offload_info_fill() is the place to fill similar fields 5206 * for offload. 5207 */ 5208 ulen = info.jited_prog_len; 5209 if (prog->aux->func_cnt) { 5210 u32 i; 5211 5212 info.jited_prog_len = 0; 5213 for (i = 0; i < prog->aux->func_cnt; i++) 5214 info.jited_prog_len += prog->aux->func[i]->jited_len; 5215 } else { 5216 info.jited_prog_len = prog->jited_len; 5217 } 5218 5219 if (info.jited_prog_len && ulen) { 5220 if (bpf_dump_raw_ok(file->f_cred)) { 5221 uinsns = u64_to_user_ptr(info.jited_prog_insns); 5222 ulen = min_t(u32, info.jited_prog_len, ulen); 5223 5224 /* for multi-function programs, copy the JITed 5225 * instructions for all the functions 5226 */ 5227 if (prog->aux->func_cnt) { 5228 u32 len, free, i; 5229 u8 *img; 5230 5231 free = ulen; 5232 for (i = 0; i < prog->aux->func_cnt; i++) { 5233 len = prog->aux->func[i]->jited_len; 5234 len = min_t(u32, len, free); 5235 img = (u8 *) prog->aux->func[i]->bpf_func; 5236 if (copy_to_user(uinsns, img, len)) 5237 return -EFAULT; 5238 uinsns += len; 5239 free -= len; 5240 if (!free) 5241 break; 5242 } 5243 } else { 5244 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 5245 return -EFAULT; 5246 } 5247 } else { 5248 info.jited_prog_insns = 0; 5249 } 5250 } 5251 5252 ulen = info.nr_jited_ksyms; 5253 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 5254 if (ulen) { 5255 if (bpf_dump_raw_ok(file->f_cred)) { 5256 unsigned long ksym_addr; 5257 u64 __user *user_ksyms; 5258 u32 i; 5259 5260 /* copy the address of the kernel symbol 5261 * corresponding to each function 5262 */ 5263 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 5264 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 5265 if (prog->aux->func_cnt) { 5266 for (i = 0; i < ulen; i++) { 5267 ksym_addr = (unsigned long) 5268 prog->aux->func[i]->bpf_func; 5269 if (put_user((u64) ksym_addr, 5270 &user_ksyms[i])) 5271 return -EFAULT; 5272 } 5273 } else { 5274 ksym_addr = (unsigned long) prog->bpf_func; 5275 if (put_user((u64) ksym_addr, &user_ksyms[0])) 5276 return -EFAULT; 5277 } 5278 } else { 5279 info.jited_ksyms = 0; 5280 } 5281 } 5282 5283 ulen = info.nr_jited_func_lens; 5284 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 5285 if (ulen) { 5286 if (bpf_dump_raw_ok(file->f_cred)) { 5287 u32 __user *user_lens; 5288 u32 func_len, i; 5289 5290 /* copy the JITed image lengths for each function */ 5291 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 5292 user_lens = u64_to_user_ptr(info.jited_func_lens); 5293 if (prog->aux->func_cnt) { 5294 for (i = 0; i < ulen; i++) { 5295 func_len = 5296 prog->aux->func[i]->jited_len; 5297 if (put_user(func_len, &user_lens[i])) 5298 return -EFAULT; 5299 } 5300 } else { 5301 func_len = prog->jited_len; 5302 if (put_user(func_len, &user_lens[0])) 5303 return -EFAULT; 5304 } 5305 } else { 5306 info.jited_func_lens = 0; 5307 } 5308 } 5309 5310 info.attach_btf_id = prog->aux->attach_btf_id; 5311 if (attach_btf) 5312 info.attach_btf_obj_id = btf_obj_id(attach_btf); 5313 5314 ulen = info.nr_func_info; 5315 info.nr_func_info = prog->aux->func_info_cnt; 5316 if (info.nr_func_info && ulen) { 5317 char __user *user_finfo; 5318 5319 user_finfo = u64_to_user_ptr(info.func_info); 5320 ulen = min_t(u32, info.nr_func_info, ulen); 5321 if (copy_to_user(user_finfo, prog->aux->func_info, 5322 info.func_info_rec_size * ulen)) 5323 return -EFAULT; 5324 } 5325 5326 ulen = info.nr_line_info; 5327 info.nr_line_info = prog->aux->nr_linfo; 5328 if (info.nr_line_info && ulen) { 5329 __u8 __user *user_linfo; 5330 5331 user_linfo = u64_to_user_ptr(info.line_info); 5332 ulen = min_t(u32, info.nr_line_info, ulen); 5333 if (copy_to_user(user_linfo, prog->aux->linfo, 5334 info.line_info_rec_size * ulen)) 5335 return -EFAULT; 5336 } 5337 5338 ulen = info.nr_jited_line_info; 5339 if (prog->aux->jited_linfo) 5340 info.nr_jited_line_info = prog->aux->nr_linfo; 5341 else 5342 info.nr_jited_line_info = 0; 5343 if (info.nr_jited_line_info && ulen) { 5344 if (bpf_dump_raw_ok(file->f_cred)) { 5345 unsigned long line_addr; 5346 __u64 __user *user_linfo; 5347 u32 i; 5348 5349 user_linfo = u64_to_user_ptr(info.jited_line_info); 5350 ulen = min_t(u32, info.nr_jited_line_info, ulen); 5351 for (i = 0; i < ulen; i++) { 5352 line_addr = (unsigned long)prog->aux->jited_linfo[i]; 5353 if (put_user((__u64)line_addr, &user_linfo[i])) 5354 return -EFAULT; 5355 } 5356 } else { 5357 info.jited_line_info = 0; 5358 } 5359 } 5360 5361 ulen = info.nr_prog_tags; 5362 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 5363 if (ulen) { 5364 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 5365 u32 i; 5366 5367 user_prog_tags = u64_to_user_ptr(info.prog_tags); 5368 ulen = min_t(u32, info.nr_prog_tags, ulen); 5369 if (prog->aux->func_cnt) { 5370 for (i = 0; i < ulen; i++) { 5371 if (copy_to_user(user_prog_tags[i], 5372 prog->aux->func[i]->tag, 5373 BPF_TAG_SIZE)) 5374 return -EFAULT; 5375 } 5376 } else { 5377 if (copy_to_user(user_prog_tags[0], 5378 prog->tag, BPF_TAG_SIZE)) 5379 return -EFAULT; 5380 } 5381 } 5382 5383 done: 5384 if (copy_to_user(uinfo, &info, info_len) || 5385 put_user(info_len, &uattr->info.info_len)) 5386 return -EFAULT; 5387 5388 return 0; 5389 } 5390 5391 static int bpf_map_get_info_by_fd(struct file *file, 5392 struct bpf_map *map, 5393 const union bpf_attr *attr, 5394 union bpf_attr __user *uattr) 5395 { 5396 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5397 struct bpf_map_info info; 5398 u32 info_len = attr->info.info_len; 5399 int err; 5400 5401 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5402 if (err) 5403 return err; 5404 info_len = min_t(u32, sizeof(info), info_len); 5405 5406 memset(&info, 0, sizeof(info)); 5407 if (copy_from_user(&info, uinfo, info_len)) 5408 return -EFAULT; 5409 5410 info.type = map->map_type; 5411 info.id = map->id; 5412 info.key_size = map->key_size; 5413 info.value_size = map->value_size; 5414 info.max_entries = map->max_entries; 5415 info.map_flags = map->map_flags; 5416 info.map_extra = map->map_extra; 5417 memcpy(info.name, map->name, sizeof(map->name)); 5418 5419 if (map->btf) { 5420 info.btf_id = btf_obj_id(map->btf); 5421 info.btf_key_type_id = map->btf_key_type_id; 5422 info.btf_value_type_id = map->btf_value_type_id; 5423 } 5424 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 5425 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) 5426 bpf_map_struct_ops_info_fill(&info, map); 5427 5428 if (bpf_map_is_offloaded(map)) { 5429 err = bpf_map_offload_info_fill(&info, map); 5430 if (err) 5431 return err; 5432 } 5433 5434 if (info.hash) { 5435 char __user *uhash = u64_to_user_ptr(info.hash); 5436 5437 if (!map->ops->map_get_hash) 5438 return -EINVAL; 5439 5440 if (info.hash_size != SHA256_DIGEST_SIZE) 5441 return -EINVAL; 5442 5443 if (!READ_ONCE(map->frozen)) 5444 return -EPERM; 5445 5446 err = map->ops->map_get_hash(map, SHA256_DIGEST_SIZE, map->sha); 5447 if (err != 0) 5448 return err; 5449 5450 if (copy_to_user(uhash, map->sha, SHA256_DIGEST_SIZE) != 0) 5451 return -EFAULT; 5452 } else if (info.hash_size) { 5453 return -EINVAL; 5454 } 5455 5456 if (copy_to_user(uinfo, &info, info_len) || 5457 put_user(info_len, &uattr->info.info_len)) 5458 return -EFAULT; 5459 5460 return 0; 5461 } 5462 5463 static int bpf_btf_get_info_by_fd(struct file *file, 5464 struct btf *btf, 5465 const union bpf_attr *attr, 5466 union bpf_attr __user *uattr) 5467 { 5468 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5469 u32 info_len = attr->info.info_len; 5470 int err; 5471 5472 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5473 if (err) 5474 return err; 5475 5476 return btf_get_info_by_fd(btf, attr, uattr); 5477 } 5478 5479 static int bpf_link_get_info_by_fd(struct file *file, 5480 struct bpf_link *link, 5481 const union bpf_attr *attr, 5482 union bpf_attr __user *uattr) 5483 { 5484 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5485 struct bpf_link_info info; 5486 u32 info_len = attr->info.info_len; 5487 int err; 5488 5489 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5490 if (err) 5491 return err; 5492 info_len = min_t(u32, sizeof(info), info_len); 5493 5494 memset(&info, 0, sizeof(info)); 5495 if (copy_from_user(&info, uinfo, info_len)) 5496 return -EFAULT; 5497 5498 info.type = link->type; 5499 info.id = link->id; 5500 if (link->prog) 5501 info.prog_id = link->prog->aux->id; 5502 5503 if (link->ops->fill_link_info) { 5504 err = link->ops->fill_link_info(link, &info); 5505 if (err) 5506 return err; 5507 } 5508 5509 if (copy_to_user(uinfo, &info, info_len) || 5510 put_user(info_len, &uattr->info.info_len)) 5511 return -EFAULT; 5512 5513 return 0; 5514 } 5515 5516 5517 static int token_get_info_by_fd(struct file *file, 5518 struct bpf_token *token, 5519 const union bpf_attr *attr, 5520 union bpf_attr __user *uattr) 5521 { 5522 struct bpf_token_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5523 u32 info_len = attr->info.info_len; 5524 int err; 5525 5526 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5527 if (err) 5528 return err; 5529 return bpf_token_get_info_by_fd(token, attr, uattr); 5530 } 5531 5532 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 5533 5534 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 5535 union bpf_attr __user *uattr) 5536 { 5537 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 5538 return -EINVAL; 5539 5540 CLASS(fd, f)(attr->info.bpf_fd); 5541 if (fd_empty(f)) 5542 return -EBADFD; 5543 5544 if (fd_file(f)->f_op == &bpf_prog_fops) 5545 return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5546 uattr); 5547 else if (fd_file(f)->f_op == &bpf_map_fops) 5548 return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5549 uattr); 5550 else if (fd_file(f)->f_op == &btf_fops) 5551 return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr); 5552 else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll) 5553 return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5554 attr, uattr); 5555 else if (fd_file(f)->f_op == &bpf_token_fops) 5556 return token_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5557 attr, uattr); 5558 return -EINVAL; 5559 } 5560 5561 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd 5562 5563 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_attr *attr_log) 5564 { 5565 struct bpf_token *token = NULL; 5566 5567 if (CHECK_ATTR(BPF_BTF_LOAD)) 5568 return -EINVAL; 5569 5570 if (attr->btf_flags & ~BPF_F_TOKEN_FD) 5571 return -EINVAL; 5572 5573 if (attr->btf_flags & BPF_F_TOKEN_FD) { 5574 token = bpf_token_get_from_fd(attr->btf_token_fd); 5575 if (IS_ERR(token)) 5576 return PTR_ERR(token); 5577 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { 5578 bpf_token_put(token); 5579 token = NULL; 5580 } 5581 } 5582 5583 if (!bpf_token_capable(token, CAP_BPF)) { 5584 bpf_token_put(token); 5585 return -EPERM; 5586 } 5587 5588 bpf_token_put(token); 5589 5590 return btf_new_fd(attr, uattr, attr_log); 5591 } 5592 5593 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD fd_by_id_token_fd 5594 5595 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 5596 { 5597 struct bpf_token *token = NULL; 5598 5599 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 5600 return -EINVAL; 5601 5602 if (attr->open_flags & ~BPF_F_TOKEN_FD) 5603 return -EINVAL; 5604 5605 if (attr->open_flags & BPF_F_TOKEN_FD) { 5606 token = bpf_token_get_from_fd(attr->fd_by_id_token_fd); 5607 if (IS_ERR(token)) 5608 return PTR_ERR(token); 5609 if (!bpf_token_allow_cmd(token, BPF_BTF_GET_FD_BY_ID)) { 5610 bpf_token_put(token); 5611 token = NULL; 5612 } 5613 } 5614 5615 if (!bpf_token_capable(token, CAP_SYS_ADMIN)) { 5616 bpf_token_put(token); 5617 return -EPERM; 5618 } 5619 5620 bpf_token_put(token); 5621 5622 return btf_get_fd_by_id(attr->btf_id); 5623 } 5624 5625 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 5626 union bpf_attr __user *uattr, 5627 u32 prog_id, u32 fd_type, 5628 const char *buf, u64 probe_offset, 5629 u64 probe_addr) 5630 { 5631 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 5632 u32 len = buf ? strlen(buf) : 0, input_len; 5633 int err = 0; 5634 5635 if (put_user(len, &uattr->task_fd_query.buf_len)) 5636 return -EFAULT; 5637 input_len = attr->task_fd_query.buf_len; 5638 if (input_len && ubuf) { 5639 if (!len) { 5640 /* nothing to copy, just make ubuf NULL terminated */ 5641 char zero = '\0'; 5642 5643 if (put_user(zero, ubuf)) 5644 return -EFAULT; 5645 } else { 5646 err = bpf_copy_to_user(ubuf, buf, input_len, len); 5647 if (err == -EFAULT) 5648 return err; 5649 } 5650 } 5651 5652 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 5653 put_user(fd_type, &uattr->task_fd_query.fd_type) || 5654 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 5655 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 5656 return -EFAULT; 5657 5658 return err; 5659 } 5660 5661 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 5662 5663 static int bpf_task_fd_query(const union bpf_attr *attr, 5664 union bpf_attr __user *uattr) 5665 { 5666 pid_t pid = attr->task_fd_query.pid; 5667 u32 fd = attr->task_fd_query.fd; 5668 const struct perf_event *event; 5669 struct task_struct *task; 5670 struct file *file; 5671 int err; 5672 5673 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 5674 return -EINVAL; 5675 5676 if (!capable(CAP_SYS_ADMIN)) 5677 return -EPERM; 5678 5679 if (attr->task_fd_query.flags != 0) 5680 return -EINVAL; 5681 5682 rcu_read_lock(); 5683 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 5684 rcu_read_unlock(); 5685 if (!task) 5686 return -ENOENT; 5687 5688 err = 0; 5689 file = fget_task(task, fd); 5690 put_task_struct(task); 5691 if (!file) 5692 return -EBADF; 5693 5694 if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) { 5695 struct bpf_link *link = file->private_data; 5696 5697 if (link->ops == &bpf_raw_tp_link_lops) { 5698 struct bpf_raw_tp_link *raw_tp = 5699 container_of(link, struct bpf_raw_tp_link, link); 5700 struct bpf_raw_event_map *btp = raw_tp->btp; 5701 5702 err = bpf_task_fd_query_copy(attr, uattr, 5703 raw_tp->link.prog->aux->id, 5704 BPF_FD_TYPE_RAW_TRACEPOINT, 5705 btp->tp->name, 0, 0); 5706 goto put_file; 5707 } 5708 goto out_not_supp; 5709 } 5710 5711 event = perf_get_event(file); 5712 if (!IS_ERR(event)) { 5713 u64 probe_offset, probe_addr; 5714 u32 prog_id, fd_type; 5715 const char *buf; 5716 5717 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 5718 &buf, &probe_offset, 5719 &probe_addr, NULL); 5720 if (!err) 5721 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 5722 fd_type, buf, 5723 probe_offset, 5724 probe_addr); 5725 goto put_file; 5726 } 5727 5728 out_not_supp: 5729 err = -ENOTSUPP; 5730 put_file: 5731 fput(file); 5732 return err; 5733 } 5734 5735 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 5736 5737 #define BPF_DO_BATCH(fn, ...) \ 5738 do { \ 5739 if (!fn) { \ 5740 err = -ENOTSUPP; \ 5741 goto err_put; \ 5742 } \ 5743 err = fn(__VA_ARGS__); \ 5744 } while (0) 5745 5746 static int bpf_map_do_batch(const union bpf_attr *attr, 5747 union bpf_attr __user *uattr, 5748 int cmd) 5749 { 5750 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 5751 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 5752 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 5753 struct bpf_map *map; 5754 int err; 5755 5756 if (CHECK_ATTR(BPF_MAP_BATCH)) 5757 return -EINVAL; 5758 5759 CLASS(fd, f)(attr->batch.map_fd); 5760 5761 map = __bpf_map_get(f); 5762 if (IS_ERR(map)) 5763 return PTR_ERR(map); 5764 if (has_write) 5765 bpf_map_write_active_inc(map); 5766 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 5767 err = -EPERM; 5768 goto err_put; 5769 } 5770 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 5771 err = -EPERM; 5772 goto err_put; 5773 } 5774 5775 if (cmd == BPF_MAP_LOOKUP_BATCH) 5776 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); 5777 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 5778 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); 5779 else if (cmd == BPF_MAP_UPDATE_BATCH) 5780 BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr); 5781 else 5782 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); 5783 err_put: 5784 if (has_write) { 5785 maybe_wait_bpf_programs(map); 5786 bpf_map_write_active_dec(map); 5787 } 5788 return err; 5789 } 5790 5791 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid 5792 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 5793 { 5794 struct bpf_prog *prog; 5795 int ret; 5796 5797 if (CHECK_ATTR(BPF_LINK_CREATE)) 5798 return -EINVAL; 5799 5800 if (attr->link_create.attach_type == BPF_STRUCT_OPS) 5801 return bpf_struct_ops_link_create(attr); 5802 5803 prog = bpf_prog_get(attr->link_create.prog_fd); 5804 if (IS_ERR(prog)) 5805 return PTR_ERR(prog); 5806 5807 ret = bpf_prog_attach_check_attach_type(prog, 5808 attr->link_create.attach_type); 5809 if (ret) 5810 goto out; 5811 5812 switch (prog->type) { 5813 case BPF_PROG_TYPE_CGROUP_SKB: 5814 case BPF_PROG_TYPE_CGROUP_SOCK: 5815 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 5816 case BPF_PROG_TYPE_SOCK_OPS: 5817 case BPF_PROG_TYPE_CGROUP_DEVICE: 5818 case BPF_PROG_TYPE_CGROUP_SYSCTL: 5819 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 5820 ret = cgroup_bpf_link_attach(attr, prog); 5821 break; 5822 case BPF_PROG_TYPE_EXT: 5823 ret = bpf_tracing_prog_attach(prog, 5824 attr->link_create.target_fd, 5825 attr->link_create.target_btf_id, 5826 attr->link_create.tracing.cookie, 5827 attr->link_create.attach_type); 5828 break; 5829 case BPF_PROG_TYPE_LSM: 5830 case BPF_PROG_TYPE_TRACING: 5831 if (attr->link_create.attach_type != prog->expected_attach_type) { 5832 ret = -EINVAL; 5833 goto out; 5834 } 5835 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 5836 ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie, 5837 attr->link_create.attach_type); 5838 else if (prog->expected_attach_type == BPF_TRACE_ITER) 5839 ret = bpf_iter_link_attach(attr, uattr, prog); 5840 else if (prog->expected_attach_type == BPF_LSM_CGROUP) 5841 ret = cgroup_bpf_link_attach(attr, prog); 5842 else 5843 ret = bpf_tracing_prog_attach(prog, 5844 attr->link_create.target_fd, 5845 attr->link_create.target_btf_id, 5846 attr->link_create.tracing.cookie, 5847 attr->link_create.attach_type); 5848 break; 5849 case BPF_PROG_TYPE_FLOW_DISSECTOR: 5850 case BPF_PROG_TYPE_SK_LOOKUP: 5851 ret = netns_bpf_link_create(attr, prog); 5852 break; 5853 case BPF_PROG_TYPE_SK_MSG: 5854 case BPF_PROG_TYPE_SK_SKB: 5855 ret = sock_map_link_create(attr, prog); 5856 break; 5857 #ifdef CONFIG_NET 5858 case BPF_PROG_TYPE_XDP: 5859 ret = bpf_xdp_link_attach(attr, prog); 5860 break; 5861 case BPF_PROG_TYPE_SCHED_CLS: 5862 if (attr->link_create.attach_type == BPF_TCX_INGRESS || 5863 attr->link_create.attach_type == BPF_TCX_EGRESS) 5864 ret = tcx_link_attach(attr, prog); 5865 else 5866 ret = netkit_link_attach(attr, prog); 5867 break; 5868 case BPF_PROG_TYPE_NETFILTER: 5869 ret = bpf_nf_link_attach(attr, prog); 5870 break; 5871 #endif 5872 case BPF_PROG_TYPE_PERF_EVENT: 5873 case BPF_PROG_TYPE_TRACEPOINT: 5874 ret = bpf_perf_link_attach(attr, prog); 5875 break; 5876 case BPF_PROG_TYPE_KPROBE: 5877 if (attr->link_create.attach_type == BPF_PERF_EVENT) 5878 ret = bpf_perf_link_attach(attr, prog); 5879 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI || 5880 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION) 5881 ret = bpf_kprobe_multi_link_attach(attr, prog); 5882 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI || 5883 attr->link_create.attach_type == BPF_TRACE_UPROBE_SESSION) 5884 ret = bpf_uprobe_multi_link_attach(attr, prog); 5885 break; 5886 default: 5887 ret = -EINVAL; 5888 } 5889 5890 out: 5891 if (ret < 0) 5892 bpf_prog_put(prog); 5893 return ret; 5894 } 5895 5896 static int link_update_map(struct bpf_link *link, union bpf_attr *attr) 5897 { 5898 struct bpf_map *new_map, *old_map = NULL; 5899 int ret; 5900 5901 new_map = bpf_map_get(attr->link_update.new_map_fd); 5902 if (IS_ERR(new_map)) 5903 return PTR_ERR(new_map); 5904 5905 if (attr->link_update.flags & BPF_F_REPLACE) { 5906 old_map = bpf_map_get(attr->link_update.old_map_fd); 5907 if (IS_ERR(old_map)) { 5908 ret = PTR_ERR(old_map); 5909 goto out_put; 5910 } 5911 } else if (attr->link_update.old_map_fd) { 5912 ret = -EINVAL; 5913 goto out_put; 5914 } 5915 5916 ret = link->ops->update_map(link, new_map, old_map); 5917 5918 if (old_map) 5919 bpf_map_put(old_map); 5920 out_put: 5921 bpf_map_put(new_map); 5922 return ret; 5923 } 5924 5925 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 5926 5927 static int link_update(union bpf_attr *attr) 5928 { 5929 struct bpf_prog *old_prog = NULL, *new_prog; 5930 struct bpf_link *link; 5931 u32 flags; 5932 int ret; 5933 5934 if (CHECK_ATTR(BPF_LINK_UPDATE)) 5935 return -EINVAL; 5936 5937 flags = attr->link_update.flags; 5938 if (flags & ~BPF_F_REPLACE) 5939 return -EINVAL; 5940 5941 link = bpf_link_get_from_fd(attr->link_update.link_fd); 5942 if (IS_ERR(link)) 5943 return PTR_ERR(link); 5944 5945 if (link->ops->update_map) { 5946 ret = link_update_map(link, attr); 5947 goto out_put_link; 5948 } 5949 5950 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 5951 if (IS_ERR(new_prog)) { 5952 ret = PTR_ERR(new_prog); 5953 goto out_put_link; 5954 } 5955 5956 if (flags & BPF_F_REPLACE) { 5957 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 5958 if (IS_ERR(old_prog)) { 5959 ret = PTR_ERR(old_prog); 5960 old_prog = NULL; 5961 goto out_put_progs; 5962 } 5963 } else if (attr->link_update.old_prog_fd) { 5964 ret = -EINVAL; 5965 goto out_put_progs; 5966 } 5967 5968 if (link->ops->update_prog) 5969 ret = link->ops->update_prog(link, new_prog, old_prog); 5970 else 5971 ret = -EINVAL; 5972 5973 out_put_progs: 5974 if (old_prog) 5975 bpf_prog_put(old_prog); 5976 if (ret) 5977 bpf_prog_put(new_prog); 5978 out_put_link: 5979 bpf_link_put_direct(link); 5980 return ret; 5981 } 5982 5983 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 5984 5985 static int link_detach(union bpf_attr *attr) 5986 { 5987 struct bpf_link *link; 5988 int ret; 5989 5990 if (CHECK_ATTR(BPF_LINK_DETACH)) 5991 return -EINVAL; 5992 5993 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 5994 if (IS_ERR(link)) 5995 return PTR_ERR(link); 5996 5997 if (link->ops->detach) 5998 ret = link->ops->detach(link); 5999 else 6000 ret = -EOPNOTSUPP; 6001 6002 bpf_link_put_direct(link); 6003 return ret; 6004 } 6005 6006 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 6007 { 6008 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 6009 } 6010 EXPORT_SYMBOL(bpf_link_inc_not_zero); 6011 6012 struct bpf_link *bpf_link_by_id(u32 id) 6013 { 6014 struct bpf_link *link; 6015 6016 if (!id) 6017 return ERR_PTR(-ENOENT); 6018 6019 spin_lock_bh(&link_idr_lock); 6020 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 6021 link = idr_find(&link_idr, id); 6022 if (link) { 6023 if (link->id) 6024 link = bpf_link_inc_not_zero(link); 6025 else 6026 link = ERR_PTR(-EAGAIN); 6027 } else { 6028 link = ERR_PTR(-ENOENT); 6029 } 6030 spin_unlock_bh(&link_idr_lock); 6031 return link; 6032 } 6033 6034 struct bpf_link *bpf_link_get_curr_or_next(u32 *id) 6035 { 6036 struct bpf_link *link; 6037 6038 spin_lock_bh(&link_idr_lock); 6039 again: 6040 link = idr_get_next(&link_idr, id); 6041 if (link) { 6042 link = bpf_link_inc_not_zero(link); 6043 if (IS_ERR(link)) { 6044 (*id)++; 6045 goto again; 6046 } 6047 } 6048 spin_unlock_bh(&link_idr_lock); 6049 6050 return link; 6051 } 6052 6053 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 6054 6055 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 6056 { 6057 struct bpf_link *link; 6058 u32 id = attr->link_id; 6059 int fd; 6060 6061 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 6062 return -EINVAL; 6063 6064 if (!capable(CAP_SYS_ADMIN)) 6065 return -EPERM; 6066 6067 link = bpf_link_by_id(id); 6068 if (IS_ERR(link)) 6069 return PTR_ERR(link); 6070 6071 fd = bpf_link_new_fd(link); 6072 if (fd < 0) 6073 bpf_link_put_direct(link); 6074 6075 return fd; 6076 } 6077 6078 DEFINE_MUTEX(bpf_stats_enabled_mutex); 6079 6080 static int bpf_stats_release(struct inode *inode, struct file *file) 6081 { 6082 mutex_lock(&bpf_stats_enabled_mutex); 6083 static_key_slow_dec(&bpf_stats_enabled_key.key); 6084 mutex_unlock(&bpf_stats_enabled_mutex); 6085 return 0; 6086 } 6087 6088 static const struct file_operations bpf_stats_fops = { 6089 .release = bpf_stats_release, 6090 }; 6091 6092 static int bpf_enable_runtime_stats(void) 6093 { 6094 int fd; 6095 6096 mutex_lock(&bpf_stats_enabled_mutex); 6097 6098 /* Set a very high limit to avoid overflow */ 6099 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 6100 mutex_unlock(&bpf_stats_enabled_mutex); 6101 return -EBUSY; 6102 } 6103 6104 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 6105 if (fd >= 0) 6106 static_key_slow_inc(&bpf_stats_enabled_key.key); 6107 6108 mutex_unlock(&bpf_stats_enabled_mutex); 6109 return fd; 6110 } 6111 6112 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 6113 6114 static int bpf_enable_stats(union bpf_attr *attr) 6115 { 6116 6117 if (CHECK_ATTR(BPF_ENABLE_STATS)) 6118 return -EINVAL; 6119 6120 if (!capable(CAP_SYS_ADMIN)) 6121 return -EPERM; 6122 6123 switch (attr->enable_stats.type) { 6124 case BPF_STATS_RUN_TIME: 6125 return bpf_enable_runtime_stats(); 6126 default: 6127 break; 6128 } 6129 return -EINVAL; 6130 } 6131 6132 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 6133 6134 static int bpf_iter_create(union bpf_attr *attr) 6135 { 6136 struct bpf_link *link; 6137 int err; 6138 6139 if (CHECK_ATTR(BPF_ITER_CREATE)) 6140 return -EINVAL; 6141 6142 if (attr->iter_create.flags) 6143 return -EINVAL; 6144 6145 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 6146 if (IS_ERR(link)) 6147 return PTR_ERR(link); 6148 6149 err = bpf_iter_new_fd(link); 6150 bpf_link_put_direct(link); 6151 6152 return err; 6153 } 6154 6155 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 6156 6157 static int bpf_prog_bind_map(union bpf_attr *attr) 6158 { 6159 struct bpf_prog *prog; 6160 struct bpf_map *map; 6161 struct bpf_map **used_maps_old, **used_maps_new; 6162 int i, ret = 0; 6163 6164 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 6165 return -EINVAL; 6166 6167 if (attr->prog_bind_map.flags) 6168 return -EINVAL; 6169 6170 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 6171 if (IS_ERR(prog)) 6172 return PTR_ERR(prog); 6173 6174 map = bpf_map_get(attr->prog_bind_map.map_fd); 6175 if (IS_ERR(map)) { 6176 ret = PTR_ERR(map); 6177 goto out_prog_put; 6178 } 6179 6180 mutex_lock(&prog->aux->used_maps_mutex); 6181 6182 used_maps_old = prog->aux->used_maps; 6183 6184 for (i = 0; i < prog->aux->used_map_cnt; i++) 6185 if (used_maps_old[i] == map) { 6186 bpf_map_put(map); 6187 goto out_unlock; 6188 } 6189 6190 used_maps_new = kmalloc_objs(used_maps_new[0], 6191 prog->aux->used_map_cnt + 1); 6192 if (!used_maps_new) { 6193 ret = -ENOMEM; 6194 goto out_unlock; 6195 } 6196 6197 /* The bpf program will not access the bpf map, but for the sake of 6198 * simplicity, increase sleepable_refcnt for sleepable program as well. 6199 */ 6200 if (prog->sleepable) 6201 atomic64_inc(&map->sleepable_refcnt); 6202 memcpy(used_maps_new, used_maps_old, 6203 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 6204 used_maps_new[prog->aux->used_map_cnt] = map; 6205 6206 prog->aux->used_map_cnt++; 6207 prog->aux->used_maps = used_maps_new; 6208 6209 kfree(used_maps_old); 6210 6211 out_unlock: 6212 mutex_unlock(&prog->aux->used_maps_mutex); 6213 6214 if (ret) 6215 bpf_map_put(map); 6216 out_prog_put: 6217 bpf_prog_put(prog); 6218 return ret; 6219 } 6220 6221 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd 6222 6223 static int token_create(union bpf_attr *attr) 6224 { 6225 if (CHECK_ATTR(BPF_TOKEN_CREATE)) 6226 return -EINVAL; 6227 6228 /* no flags are supported yet */ 6229 if (attr->token_create.flags) 6230 return -EINVAL; 6231 6232 return bpf_token_create(attr); 6233 } 6234 6235 #define BPF_PROG_STREAM_READ_BY_FD_LAST_FIELD prog_stream_read.prog_fd 6236 6237 static int prog_stream_read(union bpf_attr *attr) 6238 { 6239 char __user *buf = u64_to_user_ptr(attr->prog_stream_read.stream_buf); 6240 u32 len = attr->prog_stream_read.stream_buf_len; 6241 struct bpf_prog *prog; 6242 int ret; 6243 6244 if (CHECK_ATTR(BPF_PROG_STREAM_READ_BY_FD)) 6245 return -EINVAL; 6246 6247 prog = bpf_prog_get(attr->prog_stream_read.prog_fd); 6248 if (IS_ERR(prog)) 6249 return PTR_ERR(prog); 6250 6251 ret = bpf_prog_stream_read(prog, attr->prog_stream_read.stream_id, buf, len); 6252 bpf_prog_put(prog); 6253 6254 return ret; 6255 } 6256 6257 #define BPF_PROG_ASSOC_STRUCT_OPS_LAST_FIELD prog_assoc_struct_ops.prog_fd 6258 6259 static int prog_assoc_struct_ops(union bpf_attr *attr) 6260 { 6261 struct bpf_prog *prog; 6262 struct bpf_map *map; 6263 int ret; 6264 6265 if (CHECK_ATTR(BPF_PROG_ASSOC_STRUCT_OPS)) 6266 return -EINVAL; 6267 6268 if (attr->prog_assoc_struct_ops.flags) 6269 return -EINVAL; 6270 6271 prog = bpf_prog_get(attr->prog_assoc_struct_ops.prog_fd); 6272 if (IS_ERR(prog)) 6273 return PTR_ERR(prog); 6274 6275 if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) { 6276 ret = -EINVAL; 6277 goto put_prog; 6278 } 6279 6280 map = bpf_map_get(attr->prog_assoc_struct_ops.map_fd); 6281 if (IS_ERR(map)) { 6282 ret = PTR_ERR(map); 6283 goto put_prog; 6284 } 6285 6286 if (map->map_type != BPF_MAP_TYPE_STRUCT_OPS) { 6287 ret = -EINVAL; 6288 goto put_map; 6289 } 6290 6291 ret = bpf_prog_assoc_struct_ops(prog, map); 6292 6293 put_map: 6294 bpf_map_put(map); 6295 put_prog: 6296 bpf_prog_put(prog); 6297 return ret; 6298 } 6299 6300 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size, 6301 bpfptr_t uattr_common, unsigned int size_common) 6302 { 6303 struct bpf_common_attr attr_common; 6304 u32 offsetof_log_true_size = 0; 6305 struct bpf_log_attr attr_log; 6306 union bpf_attr attr; 6307 int err; 6308 6309 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 6310 if (err) 6311 return err; 6312 size = min_t(u32, size, sizeof(attr)); 6313 6314 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 6315 memset(&attr, 0, sizeof(attr)); 6316 if (copy_from_bpfptr(&attr, uattr, size) != 0) 6317 return -EFAULT; 6318 6319 memset(&attr_common, 0, sizeof(attr_common)); 6320 if (cmd & BPF_COMMON_ATTRS) { 6321 err = bpf_check_uarg_tail_zero(uattr_common, 6322 offsetofend(struct bpf_common_attr, log_true_size), 6323 size_common); 6324 if (err) 6325 return err; 6326 6327 cmd &= ~BPF_COMMON_ATTRS; 6328 size_common = min_t(u32, size_common, sizeof(attr_common)); 6329 if (copy_from_bpfptr(&attr_common, uattr_common, size_common) != 0) 6330 return -EFAULT; 6331 } else { 6332 size_common = 0; 6333 } 6334 6335 err = security_bpf(cmd, &attr, size, uattr.is_kernel); 6336 if (err < 0) 6337 return err; 6338 6339 switch (cmd) { 6340 case BPF_MAP_CREATE: 6341 err = map_create(&attr, uattr, &attr_common, uattr_common, size_common); 6342 break; 6343 case BPF_MAP_LOOKUP_ELEM: 6344 err = map_lookup_elem(&attr); 6345 break; 6346 case BPF_MAP_UPDATE_ELEM: 6347 err = map_update_elem(&attr, uattr); 6348 break; 6349 case BPF_MAP_DELETE_ELEM: 6350 err = map_delete_elem(&attr, uattr); 6351 break; 6352 case BPF_MAP_GET_NEXT_KEY: 6353 err = map_get_next_key(&attr); 6354 break; 6355 case BPF_MAP_FREEZE: 6356 err = map_freeze(&attr); 6357 break; 6358 case BPF_PROG_LOAD: 6359 if (size >= offsetofend(union bpf_attr, log_true_size)) 6360 offsetof_log_true_size = offsetof(union bpf_attr, log_true_size); 6361 err = bpf_log_attr_init(&attr_log, attr.log_buf, attr.log_size, attr.log_level, 6362 offsetof_log_true_size, uattr, &attr_common, uattr_common, 6363 size_common); 6364 err = err ?: bpf_prog_load(&attr, uattr, &attr_log); 6365 break; 6366 case BPF_OBJ_PIN: 6367 err = bpf_obj_pin(&attr); 6368 break; 6369 case BPF_OBJ_GET: 6370 err = bpf_obj_get(&attr); 6371 break; 6372 case BPF_PROG_ATTACH: 6373 err = bpf_prog_attach(&attr); 6374 break; 6375 case BPF_PROG_DETACH: 6376 err = bpf_prog_detach(&attr); 6377 break; 6378 case BPF_PROG_QUERY: 6379 err = bpf_prog_query(&attr, uattr.user, size); 6380 break; 6381 case BPF_PROG_TEST_RUN: 6382 err = bpf_prog_test_run(&attr, uattr.user); 6383 break; 6384 case BPF_PROG_GET_NEXT_ID: 6385 err = bpf_obj_get_next_id(&attr, uattr.user, 6386 &prog_idr, &prog_idr_lock); 6387 break; 6388 case BPF_MAP_GET_NEXT_ID: 6389 err = bpf_obj_get_next_id(&attr, uattr.user, 6390 &map_idr, &map_idr_lock); 6391 break; 6392 case BPF_BTF_GET_NEXT_ID: 6393 err = bpf_obj_get_next_id(&attr, uattr.user, 6394 &btf_idr, &btf_idr_lock); 6395 break; 6396 case BPF_PROG_GET_FD_BY_ID: 6397 err = bpf_prog_get_fd_by_id(&attr); 6398 break; 6399 case BPF_MAP_GET_FD_BY_ID: 6400 err = bpf_map_get_fd_by_id(&attr); 6401 break; 6402 case BPF_OBJ_GET_INFO_BY_FD: 6403 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 6404 break; 6405 case BPF_RAW_TRACEPOINT_OPEN: 6406 err = bpf_raw_tracepoint_open(&attr); 6407 break; 6408 case BPF_BTF_LOAD: 6409 if (size >= offsetofend(union bpf_attr, btf_log_true_size)) 6410 offsetof_log_true_size = offsetof(union bpf_attr, btf_log_true_size); 6411 err = bpf_log_attr_init(&attr_log, attr.btf_log_buf, attr.btf_log_size, 6412 attr.btf_log_level, offsetof_log_true_size, uattr, 6413 &attr_common, uattr_common, size_common); 6414 err = err ?: bpf_btf_load(&attr, uattr, &attr_log); 6415 break; 6416 case BPF_BTF_GET_FD_BY_ID: 6417 err = bpf_btf_get_fd_by_id(&attr); 6418 break; 6419 case BPF_TASK_FD_QUERY: 6420 err = bpf_task_fd_query(&attr, uattr.user); 6421 break; 6422 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 6423 err = map_lookup_and_delete_elem(&attr); 6424 break; 6425 case BPF_MAP_LOOKUP_BATCH: 6426 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 6427 break; 6428 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 6429 err = bpf_map_do_batch(&attr, uattr.user, 6430 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 6431 break; 6432 case BPF_MAP_UPDATE_BATCH: 6433 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 6434 break; 6435 case BPF_MAP_DELETE_BATCH: 6436 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 6437 break; 6438 case BPF_LINK_CREATE: 6439 err = link_create(&attr, uattr); 6440 break; 6441 case BPF_LINK_UPDATE: 6442 err = link_update(&attr); 6443 break; 6444 case BPF_LINK_GET_FD_BY_ID: 6445 err = bpf_link_get_fd_by_id(&attr); 6446 break; 6447 case BPF_LINK_GET_NEXT_ID: 6448 err = bpf_obj_get_next_id(&attr, uattr.user, 6449 &link_idr, &link_idr_lock); 6450 break; 6451 case BPF_ENABLE_STATS: 6452 err = bpf_enable_stats(&attr); 6453 break; 6454 case BPF_ITER_CREATE: 6455 err = bpf_iter_create(&attr); 6456 break; 6457 case BPF_LINK_DETACH: 6458 err = link_detach(&attr); 6459 break; 6460 case BPF_PROG_BIND_MAP: 6461 err = bpf_prog_bind_map(&attr); 6462 break; 6463 case BPF_TOKEN_CREATE: 6464 err = token_create(&attr); 6465 break; 6466 case BPF_PROG_STREAM_READ_BY_FD: 6467 err = prog_stream_read(&attr); 6468 break; 6469 case BPF_PROG_ASSOC_STRUCT_OPS: 6470 err = prog_assoc_struct_ops(&attr); 6471 break; 6472 default: 6473 err = -EINVAL; 6474 break; 6475 } 6476 6477 return err; 6478 } 6479 6480 SYSCALL_DEFINE5(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size, 6481 struct bpf_common_attr __user *, uattr_common, unsigned int, size_common) 6482 { 6483 return __sys_bpf(cmd, USER_BPFPTR(uattr), size, USER_BPFPTR(uattr_common), size_common); 6484 } 6485 6486 static bool syscall_prog_is_valid_access(int off, int size, 6487 enum bpf_access_type type, 6488 const struct bpf_prog *prog, 6489 struct bpf_insn_access_aux *info) 6490 { 6491 if (off < 0 || off >= U16_MAX) 6492 return false; 6493 /* No alignment requirements for syscall ctx accesses. */ 6494 return true; 6495 } 6496 6497 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 6498 { 6499 switch (cmd) { 6500 case BPF_MAP_CREATE: 6501 case BPF_MAP_DELETE_ELEM: 6502 case BPF_MAP_UPDATE_ELEM: 6503 case BPF_MAP_FREEZE: 6504 case BPF_MAP_GET_FD_BY_ID: 6505 case BPF_PROG_LOAD: 6506 case BPF_BTF_LOAD: 6507 case BPF_LINK_CREATE: 6508 case BPF_RAW_TRACEPOINT_OPEN: 6509 break; 6510 default: 6511 return -EINVAL; 6512 } 6513 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size, KERNEL_BPFPTR(NULL), 0); 6514 } 6515 6516 6517 /* To shut up -Wmissing-prototypes. 6518 * This function is used by the kernel light skeleton 6519 * to load bpf programs when modules are loaded or during kernel boot. 6520 * See tools/lib/bpf/skel_internal.h 6521 */ 6522 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); 6523 6524 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) 6525 { 6526 struct bpf_prog * __maybe_unused prog; 6527 struct bpf_tramp_run_ctx __maybe_unused run_ctx; 6528 6529 switch (cmd) { 6530 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 6531 case BPF_PROG_TEST_RUN: 6532 if (attr->test.data_in || attr->test.data_out || 6533 attr->test.ctx_out || attr->test.duration || 6534 attr->test.repeat || attr->test.flags) 6535 return -EINVAL; 6536 6537 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 6538 if (IS_ERR(prog)) 6539 return PTR_ERR(prog); 6540 6541 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 6542 attr->test.ctx_size_in > U16_MAX) { 6543 bpf_prog_put(prog); 6544 return -EINVAL; 6545 } 6546 6547 run_ctx.bpf_cookie = 0; 6548 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { 6549 /* recursion detected */ 6550 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); 6551 bpf_prog_put(prog); 6552 return -EBUSY; 6553 } 6554 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 6555 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, 6556 &run_ctx); 6557 bpf_prog_put(prog); 6558 return 0; 6559 #endif 6560 default: 6561 return ____bpf_sys_bpf(cmd, attr, size); 6562 } 6563 } 6564 EXPORT_SYMBOL_NS(kern_sys_bpf, "BPF_INTERNAL"); 6565 6566 static const struct bpf_func_proto bpf_sys_bpf_proto = { 6567 .func = bpf_sys_bpf, 6568 .gpl_only = false, 6569 .ret_type = RET_INTEGER, 6570 .arg1_type = ARG_ANYTHING, 6571 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 6572 .arg3_type = ARG_CONST_SIZE, 6573 }; 6574 6575 const struct bpf_func_proto * __weak 6576 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6577 { 6578 return bpf_base_func_proto(func_id, prog); 6579 } 6580 6581 BPF_CALL_1(bpf_sys_close, u32, fd) 6582 { 6583 /* When bpf program calls this helper there should not be 6584 * an fdget() without matching completed fdput(). 6585 * This helper is allowed in the following callchain only: 6586 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 6587 */ 6588 return close_fd(fd); 6589 } 6590 6591 static const struct bpf_func_proto bpf_sys_close_proto = { 6592 .func = bpf_sys_close, 6593 .gpl_only = false, 6594 .ret_type = RET_INTEGER, 6595 .arg1_type = ARG_ANYTHING, 6596 }; 6597 6598 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 6599 { 6600 *res = 0; 6601 if (flags) 6602 return -EINVAL; 6603 6604 if (name_sz <= 1 || name[name_sz - 1]) 6605 return -EINVAL; 6606 6607 if (!bpf_dump_raw_ok(current_cred())) 6608 return -EPERM; 6609 6610 *res = kallsyms_lookup_name(name); 6611 return *res ? 0 : -ENOENT; 6612 } 6613 6614 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 6615 .func = bpf_kallsyms_lookup_name, 6616 .gpl_only = false, 6617 .ret_type = RET_INTEGER, 6618 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY, 6619 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 6620 .arg3_type = ARG_ANYTHING, 6621 .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_WRITE | MEM_ALIGNED, 6622 .arg4_size = sizeof(u64), 6623 }; 6624 6625 static const struct bpf_func_proto * 6626 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6627 { 6628 switch (func_id) { 6629 case BPF_FUNC_sys_bpf: 6630 return !bpf_token_capable(prog->aux->token, CAP_PERFMON) 6631 ? NULL : &bpf_sys_bpf_proto; 6632 case BPF_FUNC_btf_find_by_name_kind: 6633 return &bpf_btf_find_by_name_kind_proto; 6634 case BPF_FUNC_sys_close: 6635 return &bpf_sys_close_proto; 6636 case BPF_FUNC_kallsyms_lookup_name: 6637 return &bpf_kallsyms_lookup_name_proto; 6638 default: 6639 return tracing_prog_func_proto(func_id, prog); 6640 } 6641 } 6642 6643 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 6644 .get_func_proto = syscall_prog_func_proto, 6645 .is_valid_access = syscall_prog_is_valid_access, 6646 }; 6647 6648 const struct bpf_prog_ops bpf_syscall_prog_ops = { 6649 .test_run = bpf_prog_test_run_syscall, 6650 }; 6651 6652 #ifdef CONFIG_SYSCTL 6653 static int bpf_stats_handler(const struct ctl_table *table, int write, 6654 void *buffer, size_t *lenp, loff_t *ppos) 6655 { 6656 struct static_key *key = (struct static_key *)table->data; 6657 static int saved_val; 6658 int val, ret; 6659 struct ctl_table tmp = { 6660 .data = &val, 6661 .maxlen = sizeof(val), 6662 .mode = table->mode, 6663 .extra1 = SYSCTL_ZERO, 6664 .extra2 = SYSCTL_ONE, 6665 }; 6666 6667 if (write && !capable(CAP_SYS_ADMIN)) 6668 return -EPERM; 6669 6670 mutex_lock(&bpf_stats_enabled_mutex); 6671 val = saved_val; 6672 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6673 if (write && !ret && val != saved_val) { 6674 if (val) 6675 static_key_slow_inc(key); 6676 else 6677 static_key_slow_dec(key); 6678 saved_val = val; 6679 } 6680 mutex_unlock(&bpf_stats_enabled_mutex); 6681 return ret; 6682 } 6683 6684 void __weak unpriv_ebpf_notify(int new_state) 6685 { 6686 } 6687 6688 static int bpf_unpriv_handler(const struct ctl_table *table, int write, 6689 void *buffer, size_t *lenp, loff_t *ppos) 6690 { 6691 int ret, unpriv_enable = *(int *)table->data; 6692 bool locked_state = unpriv_enable == 1; 6693 struct ctl_table tmp = *table; 6694 6695 if (write && !capable(CAP_SYS_ADMIN)) 6696 return -EPERM; 6697 6698 tmp.data = &unpriv_enable; 6699 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6700 if (write && !ret) { 6701 if (locked_state && unpriv_enable != 1) 6702 return -EPERM; 6703 *(int *)table->data = unpriv_enable; 6704 } 6705 6706 if (write) 6707 unpriv_ebpf_notify(unpriv_enable); 6708 6709 return ret; 6710 } 6711 6712 static const struct ctl_table bpf_syscall_table[] = { 6713 { 6714 .procname = "unprivileged_bpf_disabled", 6715 .data = &sysctl_unprivileged_bpf_disabled, 6716 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), 6717 .mode = 0644, 6718 .proc_handler = bpf_unpriv_handler, 6719 .extra1 = SYSCTL_ZERO, 6720 .extra2 = SYSCTL_TWO, 6721 }, 6722 { 6723 .procname = "bpf_stats_enabled", 6724 .data = &bpf_stats_enabled_key.key, 6725 .mode = 0644, 6726 .proc_handler = bpf_stats_handler, 6727 }, 6728 }; 6729 6730 static int __init bpf_syscall_sysctl_init(void) 6731 { 6732 register_sysctl_init("kernel", bpf_syscall_table); 6733 return 0; 6734 } 6735 late_initcall(bpf_syscall_sysctl_init); 6736 #endif /* CONFIG_SYSCTL */ 6737