1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 3 */ 4 #include <linux/bpf.h> 5 #include <linux/bpf-cgroup.h> 6 #include <linux/bpf_trace.h> 7 #include <linux/bpf_lirc.h> 8 #include <linux/bpf_verifier.h> 9 #include <linux/bsearch.h> 10 #include <linux/btf.h> 11 #include <linux/syscalls.h> 12 #include <linux/slab.h> 13 #include <linux/sched/signal.h> 14 #include <linux/vmalloc.h> 15 #include <linux/mmzone.h> 16 #include <linux/anon_inodes.h> 17 #include <linux/fdtable.h> 18 #include <linux/file.h> 19 #include <linux/fs.h> 20 #include <linux/license.h> 21 #include <linux/filter.h> 22 #include <linux/kernel.h> 23 #include <linux/idr.h> 24 #include <linux/cred.h> 25 #include <linux/timekeeping.h> 26 #include <linux/ctype.h> 27 #include <linux/nospec.h> 28 #include <linux/audit.h> 29 #include <uapi/linux/btf.h> 30 #include <linux/pgtable.h> 31 #include <linux/bpf_lsm.h> 32 #include <linux/poll.h> 33 #include <linux/sort.h> 34 #include <linux/bpf-netns.h> 35 #include <linux/rcupdate_trace.h> 36 #include <linux/memcontrol.h> 37 #include <linux/trace_events.h> 38 39 #include <net/netfilter/nf_bpf_link.h> 40 #include <net/netkit.h> 41 #include <net/tcx.h> 42 43 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 44 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 45 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 46 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 47 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 48 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 49 IS_FD_HASH(map)) 50 51 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 52 53 DEFINE_PER_CPU(int, bpf_prog_active); 54 static DEFINE_IDR(prog_idr); 55 static DEFINE_SPINLOCK(prog_idr_lock); 56 static DEFINE_IDR(map_idr); 57 static DEFINE_SPINLOCK(map_idr_lock); 58 static DEFINE_IDR(link_idr); 59 static DEFINE_SPINLOCK(link_idr_lock); 60 61 int sysctl_unprivileged_bpf_disabled __read_mostly = 62 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 63 64 static const struct bpf_map_ops * const bpf_map_types[] = { 65 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 66 #define BPF_MAP_TYPE(_id, _ops) \ 67 [_id] = &_ops, 68 #define BPF_LINK_TYPE(_id, _name) 69 #include <linux/bpf_types.h> 70 #undef BPF_PROG_TYPE 71 #undef BPF_MAP_TYPE 72 #undef BPF_LINK_TYPE 73 }; 74 75 /* 76 * If we're handed a bigger struct than we know of, ensure all the unknown bits 77 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 78 * we don't know about yet. 79 * 80 * There is a ToCToU between this function call and the following 81 * copy_from_user() call. However, this is not a concern since this function is 82 * meant to be a future-proofing of bits. 83 */ 84 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 85 size_t expected_size, 86 size_t actual_size) 87 { 88 int res; 89 90 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 91 return -E2BIG; 92 93 if (actual_size <= expected_size) 94 return 0; 95 96 if (uaddr.is_kernel) 97 res = memchr_inv(uaddr.kernel + expected_size, 0, 98 actual_size - expected_size) == NULL; 99 else 100 res = check_zeroed_user(uaddr.user + expected_size, 101 actual_size - expected_size); 102 if (res < 0) 103 return res; 104 return res ? 0 : -E2BIG; 105 } 106 107 const struct bpf_map_ops bpf_map_offload_ops = { 108 .map_meta_equal = bpf_map_meta_equal, 109 .map_alloc = bpf_map_offload_map_alloc, 110 .map_free = bpf_map_offload_map_free, 111 .map_check_btf = map_check_no_btf, 112 .map_mem_usage = bpf_map_offload_map_mem_usage, 113 }; 114 115 static void bpf_map_write_active_inc(struct bpf_map *map) 116 { 117 atomic64_inc(&map->writecnt); 118 } 119 120 static void bpf_map_write_active_dec(struct bpf_map *map) 121 { 122 atomic64_dec(&map->writecnt); 123 } 124 125 bool bpf_map_write_active(const struct bpf_map *map) 126 { 127 return atomic64_read(&map->writecnt) != 0; 128 } 129 130 static u32 bpf_map_value_size(const struct bpf_map *map) 131 { 132 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 133 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 134 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 135 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 136 return round_up(map->value_size, 8) * num_possible_cpus(); 137 else if (IS_FD_MAP(map)) 138 return sizeof(u32); 139 else 140 return map->value_size; 141 } 142 143 static void maybe_wait_bpf_programs(struct bpf_map *map) 144 { 145 /* Wait for any running non-sleepable BPF programs to complete so that 146 * userspace, when we return to it, knows that all non-sleepable 147 * programs that could be running use the new map value. For sleepable 148 * BPF programs, synchronize_rcu_tasks_trace() should be used to wait 149 * for the completions of these programs, but considering the waiting 150 * time can be very long and userspace may think it will hang forever, 151 * so don't handle sleepable BPF programs now. 152 */ 153 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 154 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 155 synchronize_rcu(); 156 } 157 158 static int bpf_map_update_value(struct bpf_map *map, struct file *map_file, 159 void *key, void *value, __u64 flags) 160 { 161 int err; 162 163 /* Need to create a kthread, thus must support schedule */ 164 if (bpf_map_is_offloaded(map)) { 165 return bpf_map_offload_update_elem(map, key, value, flags); 166 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 167 map->map_type == BPF_MAP_TYPE_ARENA || 168 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 169 return map->ops->map_update_elem(map, key, value, flags); 170 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 171 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 172 return sock_map_update_elem_sys(map, key, value, flags); 173 } else if (IS_FD_PROG_ARRAY(map)) { 174 return bpf_fd_array_map_update_elem(map, map_file, key, value, 175 flags); 176 } 177 178 bpf_disable_instrumentation(); 179 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 180 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 181 err = bpf_percpu_hash_update(map, key, value, flags); 182 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 183 err = bpf_percpu_array_update(map, key, value, flags); 184 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 185 err = bpf_percpu_cgroup_storage_update(map, key, value, 186 flags); 187 } else if (IS_FD_ARRAY(map)) { 188 err = bpf_fd_array_map_update_elem(map, map_file, key, value, 189 flags); 190 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 191 err = bpf_fd_htab_map_update_elem(map, map_file, key, value, 192 flags); 193 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 194 /* rcu_read_lock() is not needed */ 195 err = bpf_fd_reuseport_array_update_elem(map, key, value, 196 flags); 197 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 198 map->map_type == BPF_MAP_TYPE_STACK || 199 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 200 err = map->ops->map_push_elem(map, value, flags); 201 } else { 202 rcu_read_lock(); 203 err = map->ops->map_update_elem(map, key, value, flags); 204 rcu_read_unlock(); 205 } 206 bpf_enable_instrumentation(); 207 208 return err; 209 } 210 211 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 212 __u64 flags) 213 { 214 void *ptr; 215 int err; 216 217 if (bpf_map_is_offloaded(map)) 218 return bpf_map_offload_lookup_elem(map, key, value); 219 220 bpf_disable_instrumentation(); 221 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 222 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 223 err = bpf_percpu_hash_copy(map, key, value); 224 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 225 err = bpf_percpu_array_copy(map, key, value); 226 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 227 err = bpf_percpu_cgroup_storage_copy(map, key, value); 228 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 229 err = bpf_stackmap_copy(map, key, value); 230 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 231 err = bpf_fd_array_map_lookup_elem(map, key, value); 232 } else if (IS_FD_HASH(map)) { 233 err = bpf_fd_htab_map_lookup_elem(map, key, value); 234 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 235 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 236 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 237 map->map_type == BPF_MAP_TYPE_STACK || 238 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 239 err = map->ops->map_peek_elem(map, value); 240 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 241 /* struct_ops map requires directly updating "value" */ 242 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 243 } else { 244 rcu_read_lock(); 245 if (map->ops->map_lookup_elem_sys_only) 246 ptr = map->ops->map_lookup_elem_sys_only(map, key); 247 else 248 ptr = map->ops->map_lookup_elem(map, key); 249 if (IS_ERR(ptr)) { 250 err = PTR_ERR(ptr); 251 } else if (!ptr) { 252 err = -ENOENT; 253 } else { 254 err = 0; 255 if (flags & BPF_F_LOCK) 256 /* lock 'ptr' and copy everything but lock */ 257 copy_map_value_locked(map, value, ptr, true); 258 else 259 copy_map_value(map, value, ptr); 260 /* mask lock and timer, since value wasn't zero inited */ 261 check_and_init_map_value(map, value); 262 } 263 rcu_read_unlock(); 264 } 265 266 bpf_enable_instrumentation(); 267 268 return err; 269 } 270 271 /* Please, do not use this function outside from the map creation path 272 * (e.g. in map update path) without taking care of setting the active 273 * memory cgroup (see at bpf_map_kmalloc_node() for example). 274 */ 275 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 276 { 277 /* We really just want to fail instead of triggering OOM killer 278 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 279 * which is used for lower order allocation requests. 280 * 281 * It has been observed that higher order allocation requests done by 282 * vmalloc with __GFP_NORETRY being set might fail due to not trying 283 * to reclaim memory from the page cache, thus we set 284 * __GFP_RETRY_MAYFAIL to avoid such situations. 285 */ 286 287 gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO); 288 unsigned int flags = 0; 289 unsigned long align = 1; 290 void *area; 291 292 if (size >= SIZE_MAX) 293 return NULL; 294 295 /* kmalloc()'ed memory can't be mmap()'ed */ 296 if (mmapable) { 297 BUG_ON(!PAGE_ALIGNED(size)); 298 align = SHMLBA; 299 flags = VM_USERMAP; 300 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 301 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 302 numa_node); 303 if (area != NULL) 304 return area; 305 } 306 307 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 308 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 309 flags, numa_node, __builtin_return_address(0)); 310 } 311 312 void *bpf_map_area_alloc(u64 size, int numa_node) 313 { 314 return __bpf_map_area_alloc(size, numa_node, false); 315 } 316 317 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 318 { 319 return __bpf_map_area_alloc(size, numa_node, true); 320 } 321 322 void bpf_map_area_free(void *area) 323 { 324 kvfree(area); 325 } 326 327 static u32 bpf_map_flags_retain_permanent(u32 flags) 328 { 329 /* Some map creation flags are not tied to the map object but 330 * rather to the map fd instead, so they have no meaning upon 331 * map object inspection since multiple file descriptors with 332 * different (access) properties can exist here. Thus, given 333 * this has zero meaning for the map itself, lets clear these 334 * from here. 335 */ 336 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 337 } 338 339 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 340 { 341 map->map_type = attr->map_type; 342 map->key_size = attr->key_size; 343 map->value_size = attr->value_size; 344 map->max_entries = attr->max_entries; 345 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 346 map->numa_node = bpf_map_attr_numa_node(attr); 347 map->map_extra = attr->map_extra; 348 } 349 350 static int bpf_map_alloc_id(struct bpf_map *map) 351 { 352 int id; 353 354 idr_preload(GFP_KERNEL); 355 spin_lock_bh(&map_idr_lock); 356 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 357 if (id > 0) 358 map->id = id; 359 spin_unlock_bh(&map_idr_lock); 360 idr_preload_end(); 361 362 if (WARN_ON_ONCE(!id)) 363 return -ENOSPC; 364 365 return id > 0 ? 0 : id; 366 } 367 368 void bpf_map_free_id(struct bpf_map *map) 369 { 370 unsigned long flags; 371 372 /* Offloaded maps are removed from the IDR store when their device 373 * disappears - even if someone holds an fd to them they are unusable, 374 * the memory is gone, all ops will fail; they are simply waiting for 375 * refcnt to drop to be freed. 376 */ 377 if (!map->id) 378 return; 379 380 spin_lock_irqsave(&map_idr_lock, flags); 381 382 idr_remove(&map_idr, map->id); 383 map->id = 0; 384 385 spin_unlock_irqrestore(&map_idr_lock, flags); 386 } 387 388 #ifdef CONFIG_MEMCG 389 static void bpf_map_save_memcg(struct bpf_map *map) 390 { 391 /* Currently if a map is created by a process belonging to the root 392 * memory cgroup, get_obj_cgroup_from_current() will return NULL. 393 * So we have to check map->objcg for being NULL each time it's 394 * being used. 395 */ 396 if (memcg_bpf_enabled()) 397 map->objcg = get_obj_cgroup_from_current(); 398 } 399 400 static void bpf_map_release_memcg(struct bpf_map *map) 401 { 402 if (map->objcg) 403 obj_cgroup_put(map->objcg); 404 } 405 406 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map) 407 { 408 if (map->objcg) 409 return get_mem_cgroup_from_objcg(map->objcg); 410 411 return root_mem_cgroup; 412 } 413 414 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 415 int node) 416 { 417 struct mem_cgroup *memcg, *old_memcg; 418 void *ptr; 419 420 memcg = bpf_map_get_memcg(map); 421 old_memcg = set_active_memcg(memcg); 422 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 423 set_active_memcg(old_memcg); 424 mem_cgroup_put(memcg); 425 426 return ptr; 427 } 428 429 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 430 { 431 struct mem_cgroup *memcg, *old_memcg; 432 void *ptr; 433 434 memcg = bpf_map_get_memcg(map); 435 old_memcg = set_active_memcg(memcg); 436 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 437 set_active_memcg(old_memcg); 438 mem_cgroup_put(memcg); 439 440 return ptr; 441 } 442 443 void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size, 444 gfp_t flags) 445 { 446 struct mem_cgroup *memcg, *old_memcg; 447 void *ptr; 448 449 memcg = bpf_map_get_memcg(map); 450 old_memcg = set_active_memcg(memcg); 451 ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT); 452 set_active_memcg(old_memcg); 453 mem_cgroup_put(memcg); 454 455 return ptr; 456 } 457 458 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 459 size_t align, gfp_t flags) 460 { 461 struct mem_cgroup *memcg, *old_memcg; 462 void __percpu *ptr; 463 464 memcg = bpf_map_get_memcg(map); 465 old_memcg = set_active_memcg(memcg); 466 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 467 set_active_memcg(old_memcg); 468 mem_cgroup_put(memcg); 469 470 return ptr; 471 } 472 473 #else 474 static void bpf_map_save_memcg(struct bpf_map *map) 475 { 476 } 477 478 static void bpf_map_release_memcg(struct bpf_map *map) 479 { 480 } 481 #endif 482 483 int bpf_map_alloc_pages(const struct bpf_map *map, gfp_t gfp, int nid, 484 unsigned long nr_pages, struct page **pages) 485 { 486 unsigned long i, j; 487 struct page *pg; 488 int ret = 0; 489 #ifdef CONFIG_MEMCG 490 struct mem_cgroup *memcg, *old_memcg; 491 492 memcg = bpf_map_get_memcg(map); 493 old_memcg = set_active_memcg(memcg); 494 #endif 495 for (i = 0; i < nr_pages; i++) { 496 pg = alloc_pages_node(nid, gfp | __GFP_ACCOUNT, 0); 497 498 if (pg) { 499 pages[i] = pg; 500 continue; 501 } 502 for (j = 0; j < i; j++) 503 __free_page(pages[j]); 504 ret = -ENOMEM; 505 break; 506 } 507 508 #ifdef CONFIG_MEMCG 509 set_active_memcg(old_memcg); 510 mem_cgroup_put(memcg); 511 #endif 512 return ret; 513 } 514 515 516 static int btf_field_cmp(const void *a, const void *b) 517 { 518 const struct btf_field *f1 = a, *f2 = b; 519 520 if (f1->offset < f2->offset) 521 return -1; 522 else if (f1->offset > f2->offset) 523 return 1; 524 return 0; 525 } 526 527 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, 528 u32 field_mask) 529 { 530 struct btf_field *field; 531 532 if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask)) 533 return NULL; 534 field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); 535 if (!field || !(field->type & field_mask)) 536 return NULL; 537 return field; 538 } 539 540 void btf_record_free(struct btf_record *rec) 541 { 542 int i; 543 544 if (IS_ERR_OR_NULL(rec)) 545 return; 546 for (i = 0; i < rec->cnt; i++) { 547 switch (rec->fields[i].type) { 548 case BPF_KPTR_UNREF: 549 case BPF_KPTR_REF: 550 case BPF_KPTR_PERCPU: 551 if (rec->fields[i].kptr.module) 552 module_put(rec->fields[i].kptr.module); 553 if (btf_is_kernel(rec->fields[i].kptr.btf)) 554 btf_put(rec->fields[i].kptr.btf); 555 break; 556 case BPF_LIST_HEAD: 557 case BPF_LIST_NODE: 558 case BPF_RB_ROOT: 559 case BPF_RB_NODE: 560 case BPF_SPIN_LOCK: 561 case BPF_TIMER: 562 case BPF_REFCOUNT: 563 case BPF_WORKQUEUE: 564 /* Nothing to release */ 565 break; 566 default: 567 WARN_ON_ONCE(1); 568 continue; 569 } 570 } 571 kfree(rec); 572 } 573 574 void bpf_map_free_record(struct bpf_map *map) 575 { 576 btf_record_free(map->record); 577 map->record = NULL; 578 } 579 580 struct btf_record *btf_record_dup(const struct btf_record *rec) 581 { 582 const struct btf_field *fields; 583 struct btf_record *new_rec; 584 int ret, size, i; 585 586 if (IS_ERR_OR_NULL(rec)) 587 return NULL; 588 size = offsetof(struct btf_record, fields[rec->cnt]); 589 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); 590 if (!new_rec) 591 return ERR_PTR(-ENOMEM); 592 /* Do a deep copy of the btf_record */ 593 fields = rec->fields; 594 new_rec->cnt = 0; 595 for (i = 0; i < rec->cnt; i++) { 596 switch (fields[i].type) { 597 case BPF_KPTR_UNREF: 598 case BPF_KPTR_REF: 599 case BPF_KPTR_PERCPU: 600 if (btf_is_kernel(fields[i].kptr.btf)) 601 btf_get(fields[i].kptr.btf); 602 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { 603 ret = -ENXIO; 604 goto free; 605 } 606 break; 607 case BPF_LIST_HEAD: 608 case BPF_LIST_NODE: 609 case BPF_RB_ROOT: 610 case BPF_RB_NODE: 611 case BPF_SPIN_LOCK: 612 case BPF_TIMER: 613 case BPF_REFCOUNT: 614 case BPF_WORKQUEUE: 615 /* Nothing to acquire */ 616 break; 617 default: 618 ret = -EFAULT; 619 WARN_ON_ONCE(1); 620 goto free; 621 } 622 new_rec->cnt++; 623 } 624 return new_rec; 625 free: 626 btf_record_free(new_rec); 627 return ERR_PTR(ret); 628 } 629 630 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) 631 { 632 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); 633 int size; 634 635 if (!a_has_fields && !b_has_fields) 636 return true; 637 if (a_has_fields != b_has_fields) 638 return false; 639 if (rec_a->cnt != rec_b->cnt) 640 return false; 641 size = offsetof(struct btf_record, fields[rec_a->cnt]); 642 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused 643 * members are zeroed out. So memcmp is safe to do without worrying 644 * about padding/unused fields. 645 * 646 * While spin_lock, timer, and kptr have no relation to map BTF, 647 * list_head metadata is specific to map BTF, the btf and value_rec 648 * members in particular. btf is the map BTF, while value_rec points to 649 * btf_record in that map BTF. 650 * 651 * So while by default, we don't rely on the map BTF (which the records 652 * were parsed from) matching for both records, which is not backwards 653 * compatible, in case list_head is part of it, we implicitly rely on 654 * that by way of depending on memcmp succeeding for it. 655 */ 656 return !memcmp(rec_a, rec_b, size); 657 } 658 659 void bpf_obj_free_timer(const struct btf_record *rec, void *obj) 660 { 661 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) 662 return; 663 bpf_timer_cancel_and_free(obj + rec->timer_off); 664 } 665 666 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj) 667 { 668 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE))) 669 return; 670 bpf_wq_cancel_and_free(obj + rec->wq_off); 671 } 672 673 void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 674 { 675 const struct btf_field *fields; 676 int i; 677 678 if (IS_ERR_OR_NULL(rec)) 679 return; 680 fields = rec->fields; 681 for (i = 0; i < rec->cnt; i++) { 682 struct btf_struct_meta *pointee_struct_meta; 683 const struct btf_field *field = &fields[i]; 684 void *field_ptr = obj + field->offset; 685 void *xchgd_field; 686 687 switch (fields[i].type) { 688 case BPF_SPIN_LOCK: 689 break; 690 case BPF_TIMER: 691 bpf_timer_cancel_and_free(field_ptr); 692 break; 693 case BPF_WORKQUEUE: 694 bpf_wq_cancel_and_free(field_ptr); 695 break; 696 case BPF_KPTR_UNREF: 697 WRITE_ONCE(*(u64 *)field_ptr, 0); 698 break; 699 case BPF_KPTR_REF: 700 case BPF_KPTR_PERCPU: 701 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); 702 if (!xchgd_field) 703 break; 704 705 if (!btf_is_kernel(field->kptr.btf)) { 706 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, 707 field->kptr.btf_id); 708 migrate_disable(); 709 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? 710 pointee_struct_meta->record : NULL, 711 fields[i].type == BPF_KPTR_PERCPU); 712 migrate_enable(); 713 } else { 714 field->kptr.dtor(xchgd_field); 715 } 716 break; 717 case BPF_LIST_HEAD: 718 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 719 continue; 720 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); 721 break; 722 case BPF_RB_ROOT: 723 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 724 continue; 725 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); 726 break; 727 case BPF_LIST_NODE: 728 case BPF_RB_NODE: 729 case BPF_REFCOUNT: 730 break; 731 default: 732 WARN_ON_ONCE(1); 733 continue; 734 } 735 } 736 } 737 738 static void bpf_map_free(struct bpf_map *map) 739 { 740 struct btf_record *rec = map->record; 741 struct btf *btf = map->btf; 742 743 /* implementation dependent freeing */ 744 map->ops->map_free(map); 745 /* Delay freeing of btf_record for maps, as map_free 746 * callback usually needs access to them. It is better to do it here 747 * than require each callback to do the free itself manually. 748 * 749 * Note that the btf_record stashed in map->inner_map_meta->record was 750 * already freed using the map_free callback for map in map case which 751 * eventually calls bpf_map_free_meta, since inner_map_meta is only a 752 * template bpf_map struct used during verification. 753 */ 754 btf_record_free(rec); 755 /* Delay freeing of btf for maps, as map_free callback may need 756 * struct_meta info which will be freed with btf_put(). 757 */ 758 btf_put(btf); 759 } 760 761 /* called from workqueue */ 762 static void bpf_map_free_deferred(struct work_struct *work) 763 { 764 struct bpf_map *map = container_of(work, struct bpf_map, work); 765 766 security_bpf_map_free(map); 767 bpf_map_release_memcg(map); 768 bpf_map_free(map); 769 } 770 771 static void bpf_map_put_uref(struct bpf_map *map) 772 { 773 if (atomic64_dec_and_test(&map->usercnt)) { 774 if (map->ops->map_release_uref) 775 map->ops->map_release_uref(map); 776 } 777 } 778 779 static void bpf_map_free_in_work(struct bpf_map *map) 780 { 781 INIT_WORK(&map->work, bpf_map_free_deferred); 782 /* Avoid spawning kworkers, since they all might contend 783 * for the same mutex like slab_mutex. 784 */ 785 queue_work(system_unbound_wq, &map->work); 786 } 787 788 static void bpf_map_free_rcu_gp(struct rcu_head *rcu) 789 { 790 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); 791 } 792 793 static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu) 794 { 795 if (rcu_trace_implies_rcu_gp()) 796 bpf_map_free_rcu_gp(rcu); 797 else 798 call_rcu(rcu, bpf_map_free_rcu_gp); 799 } 800 801 /* decrement map refcnt and schedule it for freeing via workqueue 802 * (underlying map implementation ops->map_free() might sleep) 803 */ 804 void bpf_map_put(struct bpf_map *map) 805 { 806 if (atomic64_dec_and_test(&map->refcnt)) { 807 /* bpf_map_free_id() must be called first */ 808 bpf_map_free_id(map); 809 810 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); 811 if (READ_ONCE(map->free_after_mult_rcu_gp)) 812 call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp); 813 else if (READ_ONCE(map->free_after_rcu_gp)) 814 call_rcu(&map->rcu, bpf_map_free_rcu_gp); 815 else 816 bpf_map_free_in_work(map); 817 } 818 } 819 EXPORT_SYMBOL_GPL(bpf_map_put); 820 821 void bpf_map_put_with_uref(struct bpf_map *map) 822 { 823 bpf_map_put_uref(map); 824 bpf_map_put(map); 825 } 826 827 static int bpf_map_release(struct inode *inode, struct file *filp) 828 { 829 struct bpf_map *map = filp->private_data; 830 831 if (map->ops->map_release) 832 map->ops->map_release(map, filp); 833 834 bpf_map_put_with_uref(map); 835 return 0; 836 } 837 838 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 839 { 840 fmode_t mode = fd_file(f)->f_mode; 841 842 /* Our file permissions may have been overridden by global 843 * map permissions facing syscall side. 844 */ 845 if (READ_ONCE(map->frozen)) 846 mode &= ~FMODE_CAN_WRITE; 847 return mode; 848 } 849 850 #ifdef CONFIG_PROC_FS 851 /* Show the memory usage of a bpf map */ 852 static u64 bpf_map_memory_usage(const struct bpf_map *map) 853 { 854 return map->ops->map_mem_usage(map); 855 } 856 857 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 858 { 859 struct bpf_map *map = filp->private_data; 860 u32 type = 0, jited = 0; 861 862 if (map_type_contains_progs(map)) { 863 spin_lock(&map->owner.lock); 864 type = map->owner.type; 865 jited = map->owner.jited; 866 spin_unlock(&map->owner.lock); 867 } 868 869 seq_printf(m, 870 "map_type:\t%u\n" 871 "key_size:\t%u\n" 872 "value_size:\t%u\n" 873 "max_entries:\t%u\n" 874 "map_flags:\t%#x\n" 875 "map_extra:\t%#llx\n" 876 "memlock:\t%llu\n" 877 "map_id:\t%u\n" 878 "frozen:\t%u\n", 879 map->map_type, 880 map->key_size, 881 map->value_size, 882 map->max_entries, 883 map->map_flags, 884 (unsigned long long)map->map_extra, 885 bpf_map_memory_usage(map), 886 map->id, 887 READ_ONCE(map->frozen)); 888 if (type) { 889 seq_printf(m, "owner_prog_type:\t%u\n", type); 890 seq_printf(m, "owner_jited:\t%u\n", jited); 891 } 892 } 893 #endif 894 895 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 896 loff_t *ppos) 897 { 898 /* We need this handler such that alloc_file() enables 899 * f_mode with FMODE_CAN_READ. 900 */ 901 return -EINVAL; 902 } 903 904 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 905 size_t siz, loff_t *ppos) 906 { 907 /* We need this handler such that alloc_file() enables 908 * f_mode with FMODE_CAN_WRITE. 909 */ 910 return -EINVAL; 911 } 912 913 /* called for any extra memory-mapped regions (except initial) */ 914 static void bpf_map_mmap_open(struct vm_area_struct *vma) 915 { 916 struct bpf_map *map = vma->vm_file->private_data; 917 918 if (vma->vm_flags & VM_MAYWRITE) 919 bpf_map_write_active_inc(map); 920 } 921 922 /* called for all unmapped memory region (including initial) */ 923 static void bpf_map_mmap_close(struct vm_area_struct *vma) 924 { 925 struct bpf_map *map = vma->vm_file->private_data; 926 927 if (vma->vm_flags & VM_MAYWRITE) 928 bpf_map_write_active_dec(map); 929 } 930 931 static const struct vm_operations_struct bpf_map_default_vmops = { 932 .open = bpf_map_mmap_open, 933 .close = bpf_map_mmap_close, 934 }; 935 936 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 937 { 938 struct bpf_map *map = filp->private_data; 939 int err; 940 941 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) 942 return -ENOTSUPP; 943 944 if (!(vma->vm_flags & VM_SHARED)) 945 return -EINVAL; 946 947 mutex_lock(&map->freeze_mutex); 948 949 if (vma->vm_flags & VM_WRITE) { 950 if (map->frozen) { 951 err = -EPERM; 952 goto out; 953 } 954 /* map is meant to be read-only, so do not allow mapping as 955 * writable, because it's possible to leak a writable page 956 * reference and allows user-space to still modify it after 957 * freezing, while verifier will assume contents do not change 958 */ 959 if (map->map_flags & BPF_F_RDONLY_PROG) { 960 err = -EACCES; 961 goto out; 962 } 963 } 964 965 /* set default open/close callbacks */ 966 vma->vm_ops = &bpf_map_default_vmops; 967 vma->vm_private_data = map; 968 vm_flags_clear(vma, VM_MAYEXEC); 969 if (!(vma->vm_flags & VM_WRITE)) 970 /* disallow re-mapping with PROT_WRITE */ 971 vm_flags_clear(vma, VM_MAYWRITE); 972 973 err = map->ops->map_mmap(map, vma); 974 if (err) 975 goto out; 976 977 if (vma->vm_flags & VM_MAYWRITE) 978 bpf_map_write_active_inc(map); 979 out: 980 mutex_unlock(&map->freeze_mutex); 981 return err; 982 } 983 984 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 985 { 986 struct bpf_map *map = filp->private_data; 987 988 if (map->ops->map_poll) 989 return map->ops->map_poll(map, filp, pts); 990 991 return EPOLLERR; 992 } 993 994 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, 995 unsigned long len, unsigned long pgoff, 996 unsigned long flags) 997 { 998 struct bpf_map *map = filp->private_data; 999 1000 if (map->ops->map_get_unmapped_area) 1001 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); 1002 #ifdef CONFIG_MMU 1003 return mm_get_unmapped_area(current->mm, filp, addr, len, pgoff, flags); 1004 #else 1005 return addr; 1006 #endif 1007 } 1008 1009 const struct file_operations bpf_map_fops = { 1010 #ifdef CONFIG_PROC_FS 1011 .show_fdinfo = bpf_map_show_fdinfo, 1012 #endif 1013 .release = bpf_map_release, 1014 .read = bpf_dummy_read, 1015 .write = bpf_dummy_write, 1016 .mmap = bpf_map_mmap, 1017 .poll = bpf_map_poll, 1018 .get_unmapped_area = bpf_get_unmapped_area, 1019 }; 1020 1021 int bpf_map_new_fd(struct bpf_map *map, int flags) 1022 { 1023 int ret; 1024 1025 ret = security_bpf_map(map, OPEN_FMODE(flags)); 1026 if (ret < 0) 1027 return ret; 1028 1029 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 1030 flags | O_CLOEXEC); 1031 } 1032 1033 int bpf_get_file_flag(int flags) 1034 { 1035 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 1036 return -EINVAL; 1037 if (flags & BPF_F_RDONLY) 1038 return O_RDONLY; 1039 if (flags & BPF_F_WRONLY) 1040 return O_WRONLY; 1041 return O_RDWR; 1042 } 1043 1044 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 1045 #define CHECK_ATTR(CMD) \ 1046 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 1047 sizeof(attr->CMD##_LAST_FIELD), 0, \ 1048 sizeof(*attr) - \ 1049 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 1050 sizeof(attr->CMD##_LAST_FIELD)) != NULL 1051 1052 /* dst and src must have at least "size" number of bytes. 1053 * Return strlen on success and < 0 on error. 1054 */ 1055 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 1056 { 1057 const char *end = src + size; 1058 const char *orig_src = src; 1059 1060 memset(dst, 0, size); 1061 /* Copy all isalnum(), '_' and '.' chars. */ 1062 while (src < end && *src) { 1063 if (!isalnum(*src) && 1064 *src != '_' && *src != '.') 1065 return -EINVAL; 1066 *dst++ = *src++; 1067 } 1068 1069 /* No '\0' found in "size" number of bytes */ 1070 if (src == end) 1071 return -EINVAL; 1072 1073 return src - orig_src; 1074 } 1075 1076 int map_check_no_btf(const struct bpf_map *map, 1077 const struct btf *btf, 1078 const struct btf_type *key_type, 1079 const struct btf_type *value_type) 1080 { 1081 return -ENOTSUPP; 1082 } 1083 1084 static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 1085 const struct btf *btf, u32 btf_key_id, u32 btf_value_id) 1086 { 1087 const struct btf_type *key_type, *value_type; 1088 u32 key_size, value_size; 1089 int ret = 0; 1090 1091 /* Some maps allow key to be unspecified. */ 1092 if (btf_key_id) { 1093 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 1094 if (!key_type || key_size != map->key_size) 1095 return -EINVAL; 1096 } else { 1097 key_type = btf_type_by_id(btf, 0); 1098 if (!map->ops->map_check_btf) 1099 return -EINVAL; 1100 } 1101 1102 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 1103 if (!value_type || value_size != map->value_size) 1104 return -EINVAL; 1105 1106 map->record = btf_parse_fields(btf, value_type, 1107 BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | 1108 BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE, 1109 map->value_size); 1110 if (!IS_ERR_OR_NULL(map->record)) { 1111 int i; 1112 1113 if (!bpf_token_capable(token, CAP_BPF)) { 1114 ret = -EPERM; 1115 goto free_map_tab; 1116 } 1117 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { 1118 ret = -EACCES; 1119 goto free_map_tab; 1120 } 1121 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { 1122 switch (map->record->field_mask & (1 << i)) { 1123 case 0: 1124 continue; 1125 case BPF_SPIN_LOCK: 1126 if (map->map_type != BPF_MAP_TYPE_HASH && 1127 map->map_type != BPF_MAP_TYPE_ARRAY && 1128 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 1129 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1130 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1131 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1132 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1133 ret = -EOPNOTSUPP; 1134 goto free_map_tab; 1135 } 1136 break; 1137 case BPF_TIMER: 1138 case BPF_WORKQUEUE: 1139 if (map->map_type != BPF_MAP_TYPE_HASH && 1140 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1141 map->map_type != BPF_MAP_TYPE_ARRAY) { 1142 ret = -EOPNOTSUPP; 1143 goto free_map_tab; 1144 } 1145 break; 1146 case BPF_KPTR_UNREF: 1147 case BPF_KPTR_REF: 1148 case BPF_KPTR_PERCPU: 1149 case BPF_REFCOUNT: 1150 if (map->map_type != BPF_MAP_TYPE_HASH && 1151 map->map_type != BPF_MAP_TYPE_PERCPU_HASH && 1152 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1153 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && 1154 map->map_type != BPF_MAP_TYPE_ARRAY && 1155 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && 1156 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1157 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1158 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1159 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1160 ret = -EOPNOTSUPP; 1161 goto free_map_tab; 1162 } 1163 break; 1164 case BPF_LIST_HEAD: 1165 case BPF_RB_ROOT: 1166 if (map->map_type != BPF_MAP_TYPE_HASH && 1167 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1168 map->map_type != BPF_MAP_TYPE_ARRAY) { 1169 ret = -EOPNOTSUPP; 1170 goto free_map_tab; 1171 } 1172 break; 1173 default: 1174 /* Fail if map_type checks are missing for a field type */ 1175 ret = -EOPNOTSUPP; 1176 goto free_map_tab; 1177 } 1178 } 1179 } 1180 1181 ret = btf_check_and_fixup_fields(btf, map->record); 1182 if (ret < 0) 1183 goto free_map_tab; 1184 1185 if (map->ops->map_check_btf) { 1186 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 1187 if (ret < 0) 1188 goto free_map_tab; 1189 } 1190 1191 return ret; 1192 free_map_tab: 1193 bpf_map_free_record(map); 1194 return ret; 1195 } 1196 1197 static bool bpf_net_capable(void) 1198 { 1199 return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN); 1200 } 1201 1202 #define BPF_MAP_CREATE_LAST_FIELD map_token_fd 1203 /* called via syscall */ 1204 static int map_create(union bpf_attr *attr) 1205 { 1206 const struct bpf_map_ops *ops; 1207 struct bpf_token *token = NULL; 1208 int numa_node = bpf_map_attr_numa_node(attr); 1209 u32 map_type = attr->map_type; 1210 struct bpf_map *map; 1211 bool token_flag; 1212 int f_flags; 1213 int err; 1214 1215 err = CHECK_ATTR(BPF_MAP_CREATE); 1216 if (err) 1217 return -EINVAL; 1218 1219 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it 1220 * to avoid per-map type checks tripping on unknown flag 1221 */ 1222 token_flag = attr->map_flags & BPF_F_TOKEN_FD; 1223 attr->map_flags &= ~BPF_F_TOKEN_FD; 1224 1225 if (attr->btf_vmlinux_value_type_id) { 1226 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 1227 attr->btf_key_type_id || attr->btf_value_type_id) 1228 return -EINVAL; 1229 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 1230 return -EINVAL; 1231 } 1232 1233 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 1234 attr->map_type != BPF_MAP_TYPE_ARENA && 1235 attr->map_extra != 0) 1236 return -EINVAL; 1237 1238 f_flags = bpf_get_file_flag(attr->map_flags); 1239 if (f_flags < 0) 1240 return f_flags; 1241 1242 if (numa_node != NUMA_NO_NODE && 1243 ((unsigned int)numa_node >= nr_node_ids || 1244 !node_online(numa_node))) 1245 return -EINVAL; 1246 1247 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 1248 map_type = attr->map_type; 1249 if (map_type >= ARRAY_SIZE(bpf_map_types)) 1250 return -EINVAL; 1251 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); 1252 ops = bpf_map_types[map_type]; 1253 if (!ops) 1254 return -EINVAL; 1255 1256 if (ops->map_alloc_check) { 1257 err = ops->map_alloc_check(attr); 1258 if (err) 1259 return err; 1260 } 1261 if (attr->map_ifindex) 1262 ops = &bpf_map_offload_ops; 1263 if (!ops->map_mem_usage) 1264 return -EINVAL; 1265 1266 if (token_flag) { 1267 token = bpf_token_get_from_fd(attr->map_token_fd); 1268 if (IS_ERR(token)) 1269 return PTR_ERR(token); 1270 1271 /* if current token doesn't grant map creation permissions, 1272 * then we can't use this token, so ignore it and rely on 1273 * system-wide capabilities checks 1274 */ 1275 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || 1276 !bpf_token_allow_map_type(token, attr->map_type)) { 1277 bpf_token_put(token); 1278 token = NULL; 1279 } 1280 } 1281 1282 err = -EPERM; 1283 1284 /* Intent here is for unprivileged_bpf_disabled to block BPF map 1285 * creation for unprivileged users; other actions depend 1286 * on fd availability and access to bpffs, so are dependent on 1287 * object creation success. Even with unprivileged BPF disabled, 1288 * capability checks are still carried out. 1289 */ 1290 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) 1291 goto put_token; 1292 1293 /* check privileged map type permissions */ 1294 switch (map_type) { 1295 case BPF_MAP_TYPE_ARRAY: 1296 case BPF_MAP_TYPE_PERCPU_ARRAY: 1297 case BPF_MAP_TYPE_PROG_ARRAY: 1298 case BPF_MAP_TYPE_PERF_EVENT_ARRAY: 1299 case BPF_MAP_TYPE_CGROUP_ARRAY: 1300 case BPF_MAP_TYPE_ARRAY_OF_MAPS: 1301 case BPF_MAP_TYPE_HASH: 1302 case BPF_MAP_TYPE_PERCPU_HASH: 1303 case BPF_MAP_TYPE_HASH_OF_MAPS: 1304 case BPF_MAP_TYPE_RINGBUF: 1305 case BPF_MAP_TYPE_USER_RINGBUF: 1306 case BPF_MAP_TYPE_CGROUP_STORAGE: 1307 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: 1308 /* unprivileged */ 1309 break; 1310 case BPF_MAP_TYPE_SK_STORAGE: 1311 case BPF_MAP_TYPE_INODE_STORAGE: 1312 case BPF_MAP_TYPE_TASK_STORAGE: 1313 case BPF_MAP_TYPE_CGRP_STORAGE: 1314 case BPF_MAP_TYPE_BLOOM_FILTER: 1315 case BPF_MAP_TYPE_LPM_TRIE: 1316 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: 1317 case BPF_MAP_TYPE_STACK_TRACE: 1318 case BPF_MAP_TYPE_QUEUE: 1319 case BPF_MAP_TYPE_STACK: 1320 case BPF_MAP_TYPE_LRU_HASH: 1321 case BPF_MAP_TYPE_LRU_PERCPU_HASH: 1322 case BPF_MAP_TYPE_STRUCT_OPS: 1323 case BPF_MAP_TYPE_CPUMAP: 1324 case BPF_MAP_TYPE_ARENA: 1325 if (!bpf_token_capable(token, CAP_BPF)) 1326 goto put_token; 1327 break; 1328 case BPF_MAP_TYPE_SOCKMAP: 1329 case BPF_MAP_TYPE_SOCKHASH: 1330 case BPF_MAP_TYPE_DEVMAP: 1331 case BPF_MAP_TYPE_DEVMAP_HASH: 1332 case BPF_MAP_TYPE_XSKMAP: 1333 if (!bpf_token_capable(token, CAP_NET_ADMIN)) 1334 goto put_token; 1335 break; 1336 default: 1337 WARN(1, "unsupported map type %d", map_type); 1338 goto put_token; 1339 } 1340 1341 map = ops->map_alloc(attr); 1342 if (IS_ERR(map)) { 1343 err = PTR_ERR(map); 1344 goto put_token; 1345 } 1346 map->ops = ops; 1347 map->map_type = map_type; 1348 1349 err = bpf_obj_name_cpy(map->name, attr->map_name, 1350 sizeof(attr->map_name)); 1351 if (err < 0) 1352 goto free_map; 1353 1354 atomic64_set(&map->refcnt, 1); 1355 atomic64_set(&map->usercnt, 1); 1356 mutex_init(&map->freeze_mutex); 1357 spin_lock_init(&map->owner.lock); 1358 1359 if (attr->btf_key_type_id || attr->btf_value_type_id || 1360 /* Even the map's value is a kernel's struct, 1361 * the bpf_prog.o must have BTF to begin with 1362 * to figure out the corresponding kernel's 1363 * counter part. Thus, attr->btf_fd has 1364 * to be valid also. 1365 */ 1366 attr->btf_vmlinux_value_type_id) { 1367 struct btf *btf; 1368 1369 btf = btf_get_by_fd(attr->btf_fd); 1370 if (IS_ERR(btf)) { 1371 err = PTR_ERR(btf); 1372 goto free_map; 1373 } 1374 if (btf_is_kernel(btf)) { 1375 btf_put(btf); 1376 err = -EACCES; 1377 goto free_map; 1378 } 1379 map->btf = btf; 1380 1381 if (attr->btf_value_type_id) { 1382 err = map_check_btf(map, token, btf, attr->btf_key_type_id, 1383 attr->btf_value_type_id); 1384 if (err) 1385 goto free_map; 1386 } 1387 1388 map->btf_key_type_id = attr->btf_key_type_id; 1389 map->btf_value_type_id = attr->btf_value_type_id; 1390 map->btf_vmlinux_value_type_id = 1391 attr->btf_vmlinux_value_type_id; 1392 } 1393 1394 err = security_bpf_map_create(map, attr, token); 1395 if (err) 1396 goto free_map_sec; 1397 1398 err = bpf_map_alloc_id(map); 1399 if (err) 1400 goto free_map_sec; 1401 1402 bpf_map_save_memcg(map); 1403 bpf_token_put(token); 1404 1405 err = bpf_map_new_fd(map, f_flags); 1406 if (err < 0) { 1407 /* failed to allocate fd. 1408 * bpf_map_put_with_uref() is needed because the above 1409 * bpf_map_alloc_id() has published the map 1410 * to the userspace and the userspace may 1411 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 1412 */ 1413 bpf_map_put_with_uref(map); 1414 return err; 1415 } 1416 1417 return err; 1418 1419 free_map_sec: 1420 security_bpf_map_free(map); 1421 free_map: 1422 bpf_map_free(map); 1423 put_token: 1424 bpf_token_put(token); 1425 return err; 1426 } 1427 1428 void bpf_map_inc(struct bpf_map *map) 1429 { 1430 atomic64_inc(&map->refcnt); 1431 } 1432 EXPORT_SYMBOL_GPL(bpf_map_inc); 1433 1434 void bpf_map_inc_with_uref(struct bpf_map *map) 1435 { 1436 atomic64_inc(&map->refcnt); 1437 atomic64_inc(&map->usercnt); 1438 } 1439 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 1440 1441 struct bpf_map *bpf_map_get(u32 ufd) 1442 { 1443 CLASS(fd, f)(ufd); 1444 struct bpf_map *map = __bpf_map_get(f); 1445 1446 if (!IS_ERR(map)) 1447 bpf_map_inc(map); 1448 1449 return map; 1450 } 1451 EXPORT_SYMBOL(bpf_map_get); 1452 1453 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 1454 { 1455 CLASS(fd, f)(ufd); 1456 struct bpf_map *map = __bpf_map_get(f); 1457 1458 if (!IS_ERR(map)) 1459 bpf_map_inc_with_uref(map); 1460 1461 return map; 1462 } 1463 1464 /* map_idr_lock should have been held or the map should have been 1465 * protected by rcu read lock. 1466 */ 1467 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1468 { 1469 int refold; 1470 1471 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1472 if (!refold) 1473 return ERR_PTR(-ENOENT); 1474 if (uref) 1475 atomic64_inc(&map->usercnt); 1476 1477 return map; 1478 } 1479 1480 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1481 { 1482 spin_lock_bh(&map_idr_lock); 1483 map = __bpf_map_inc_not_zero(map, false); 1484 spin_unlock_bh(&map_idr_lock); 1485 1486 return map; 1487 } 1488 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1489 1490 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1491 { 1492 return -ENOTSUPP; 1493 } 1494 1495 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1496 { 1497 if (key_size) 1498 return vmemdup_user(ukey, key_size); 1499 1500 if (ukey) 1501 return ERR_PTR(-EINVAL); 1502 1503 return NULL; 1504 } 1505 1506 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1507 { 1508 if (key_size) 1509 return kvmemdup_bpfptr(ukey, key_size); 1510 1511 if (!bpfptr_is_null(ukey)) 1512 return ERR_PTR(-EINVAL); 1513 1514 return NULL; 1515 } 1516 1517 /* last field in 'union bpf_attr' used by this command */ 1518 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1519 1520 static int map_lookup_elem(union bpf_attr *attr) 1521 { 1522 void __user *ukey = u64_to_user_ptr(attr->key); 1523 void __user *uvalue = u64_to_user_ptr(attr->value); 1524 struct bpf_map *map; 1525 void *key, *value; 1526 u32 value_size; 1527 int err; 1528 1529 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1530 return -EINVAL; 1531 1532 if (attr->flags & ~BPF_F_LOCK) 1533 return -EINVAL; 1534 1535 CLASS(fd, f)(attr->map_fd); 1536 map = __bpf_map_get(f); 1537 if (IS_ERR(map)) 1538 return PTR_ERR(map); 1539 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1540 return -EPERM; 1541 1542 if ((attr->flags & BPF_F_LOCK) && 1543 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) 1544 return -EINVAL; 1545 1546 key = __bpf_copy_key(ukey, map->key_size); 1547 if (IS_ERR(key)) 1548 return PTR_ERR(key); 1549 1550 value_size = bpf_map_value_size(map); 1551 1552 err = -ENOMEM; 1553 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1554 if (!value) 1555 goto free_key; 1556 1557 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1558 if (copy_from_user(value, uvalue, value_size)) 1559 err = -EFAULT; 1560 else 1561 err = bpf_map_copy_value(map, key, value, attr->flags); 1562 goto free_value; 1563 } 1564 1565 err = bpf_map_copy_value(map, key, value, attr->flags); 1566 if (err) 1567 goto free_value; 1568 1569 err = -EFAULT; 1570 if (copy_to_user(uvalue, value, value_size) != 0) 1571 goto free_value; 1572 1573 err = 0; 1574 1575 free_value: 1576 kvfree(value); 1577 free_key: 1578 kvfree(key); 1579 return err; 1580 } 1581 1582 1583 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1584 1585 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1586 { 1587 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1588 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1589 struct bpf_map *map; 1590 void *key, *value; 1591 u32 value_size; 1592 int err; 1593 1594 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1595 return -EINVAL; 1596 1597 CLASS(fd, f)(attr->map_fd); 1598 map = __bpf_map_get(f); 1599 if (IS_ERR(map)) 1600 return PTR_ERR(map); 1601 bpf_map_write_active_inc(map); 1602 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1603 err = -EPERM; 1604 goto err_put; 1605 } 1606 1607 if ((attr->flags & BPF_F_LOCK) && 1608 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1609 err = -EINVAL; 1610 goto err_put; 1611 } 1612 1613 key = ___bpf_copy_key(ukey, map->key_size); 1614 if (IS_ERR(key)) { 1615 err = PTR_ERR(key); 1616 goto err_put; 1617 } 1618 1619 value_size = bpf_map_value_size(map); 1620 value = kvmemdup_bpfptr(uvalue, value_size); 1621 if (IS_ERR(value)) { 1622 err = PTR_ERR(value); 1623 goto free_key; 1624 } 1625 1626 err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags); 1627 if (!err) 1628 maybe_wait_bpf_programs(map); 1629 1630 kvfree(value); 1631 free_key: 1632 kvfree(key); 1633 err_put: 1634 bpf_map_write_active_dec(map); 1635 return err; 1636 } 1637 1638 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1639 1640 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) 1641 { 1642 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1643 struct bpf_map *map; 1644 void *key; 1645 int err; 1646 1647 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1648 return -EINVAL; 1649 1650 CLASS(fd, f)(attr->map_fd); 1651 map = __bpf_map_get(f); 1652 if (IS_ERR(map)) 1653 return PTR_ERR(map); 1654 bpf_map_write_active_inc(map); 1655 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1656 err = -EPERM; 1657 goto err_put; 1658 } 1659 1660 key = ___bpf_copy_key(ukey, map->key_size); 1661 if (IS_ERR(key)) { 1662 err = PTR_ERR(key); 1663 goto err_put; 1664 } 1665 1666 if (bpf_map_is_offloaded(map)) { 1667 err = bpf_map_offload_delete_elem(map, key); 1668 goto out; 1669 } else if (IS_FD_PROG_ARRAY(map) || 1670 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1671 /* These maps require sleepable context */ 1672 err = map->ops->map_delete_elem(map, key); 1673 goto out; 1674 } 1675 1676 bpf_disable_instrumentation(); 1677 rcu_read_lock(); 1678 err = map->ops->map_delete_elem(map, key); 1679 rcu_read_unlock(); 1680 bpf_enable_instrumentation(); 1681 if (!err) 1682 maybe_wait_bpf_programs(map); 1683 out: 1684 kvfree(key); 1685 err_put: 1686 bpf_map_write_active_dec(map); 1687 return err; 1688 } 1689 1690 /* last field in 'union bpf_attr' used by this command */ 1691 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1692 1693 static int map_get_next_key(union bpf_attr *attr) 1694 { 1695 void __user *ukey = u64_to_user_ptr(attr->key); 1696 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1697 struct bpf_map *map; 1698 void *key, *next_key; 1699 int err; 1700 1701 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1702 return -EINVAL; 1703 1704 CLASS(fd, f)(attr->map_fd); 1705 map = __bpf_map_get(f); 1706 if (IS_ERR(map)) 1707 return PTR_ERR(map); 1708 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1709 return -EPERM; 1710 1711 if (ukey) { 1712 key = __bpf_copy_key(ukey, map->key_size); 1713 if (IS_ERR(key)) 1714 return PTR_ERR(key); 1715 } else { 1716 key = NULL; 1717 } 1718 1719 err = -ENOMEM; 1720 next_key = kvmalloc(map->key_size, GFP_USER); 1721 if (!next_key) 1722 goto free_key; 1723 1724 if (bpf_map_is_offloaded(map)) { 1725 err = bpf_map_offload_get_next_key(map, key, next_key); 1726 goto out; 1727 } 1728 1729 rcu_read_lock(); 1730 err = map->ops->map_get_next_key(map, key, next_key); 1731 rcu_read_unlock(); 1732 out: 1733 if (err) 1734 goto free_next_key; 1735 1736 err = -EFAULT; 1737 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1738 goto free_next_key; 1739 1740 err = 0; 1741 1742 free_next_key: 1743 kvfree(next_key); 1744 free_key: 1745 kvfree(key); 1746 return err; 1747 } 1748 1749 int generic_map_delete_batch(struct bpf_map *map, 1750 const union bpf_attr *attr, 1751 union bpf_attr __user *uattr) 1752 { 1753 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1754 u32 cp, max_count; 1755 int err = 0; 1756 void *key; 1757 1758 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1759 return -EINVAL; 1760 1761 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1762 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1763 return -EINVAL; 1764 } 1765 1766 max_count = attr->batch.count; 1767 if (!max_count) 1768 return 0; 1769 1770 if (put_user(0, &uattr->batch.count)) 1771 return -EFAULT; 1772 1773 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1774 if (!key) 1775 return -ENOMEM; 1776 1777 for (cp = 0; cp < max_count; cp++) { 1778 err = -EFAULT; 1779 if (copy_from_user(key, keys + cp * map->key_size, 1780 map->key_size)) 1781 break; 1782 1783 if (bpf_map_is_offloaded(map)) { 1784 err = bpf_map_offload_delete_elem(map, key); 1785 break; 1786 } 1787 1788 bpf_disable_instrumentation(); 1789 rcu_read_lock(); 1790 err = map->ops->map_delete_elem(map, key); 1791 rcu_read_unlock(); 1792 bpf_enable_instrumentation(); 1793 if (err) 1794 break; 1795 cond_resched(); 1796 } 1797 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1798 err = -EFAULT; 1799 1800 kvfree(key); 1801 1802 return err; 1803 } 1804 1805 int generic_map_update_batch(struct bpf_map *map, struct file *map_file, 1806 const union bpf_attr *attr, 1807 union bpf_attr __user *uattr) 1808 { 1809 void __user *values = u64_to_user_ptr(attr->batch.values); 1810 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1811 u32 value_size, cp, max_count; 1812 void *key, *value; 1813 int err = 0; 1814 1815 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1816 return -EINVAL; 1817 1818 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1819 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1820 return -EINVAL; 1821 } 1822 1823 value_size = bpf_map_value_size(map); 1824 1825 max_count = attr->batch.count; 1826 if (!max_count) 1827 return 0; 1828 1829 if (put_user(0, &uattr->batch.count)) 1830 return -EFAULT; 1831 1832 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1833 if (!key) 1834 return -ENOMEM; 1835 1836 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1837 if (!value) { 1838 kvfree(key); 1839 return -ENOMEM; 1840 } 1841 1842 for (cp = 0; cp < max_count; cp++) { 1843 err = -EFAULT; 1844 if (copy_from_user(key, keys + cp * map->key_size, 1845 map->key_size) || 1846 copy_from_user(value, values + cp * value_size, value_size)) 1847 break; 1848 1849 err = bpf_map_update_value(map, map_file, key, value, 1850 attr->batch.elem_flags); 1851 1852 if (err) 1853 break; 1854 cond_resched(); 1855 } 1856 1857 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1858 err = -EFAULT; 1859 1860 kvfree(value); 1861 kvfree(key); 1862 1863 return err; 1864 } 1865 1866 #define MAP_LOOKUP_RETRIES 3 1867 1868 int generic_map_lookup_batch(struct bpf_map *map, 1869 const union bpf_attr *attr, 1870 union bpf_attr __user *uattr) 1871 { 1872 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1873 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1874 void __user *values = u64_to_user_ptr(attr->batch.values); 1875 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1876 void *buf, *buf_prevkey, *prev_key, *key, *value; 1877 int err, retry = MAP_LOOKUP_RETRIES; 1878 u32 value_size, cp, max_count; 1879 1880 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1881 return -EINVAL; 1882 1883 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1884 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) 1885 return -EINVAL; 1886 1887 value_size = bpf_map_value_size(map); 1888 1889 max_count = attr->batch.count; 1890 if (!max_count) 1891 return 0; 1892 1893 if (put_user(0, &uattr->batch.count)) 1894 return -EFAULT; 1895 1896 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1897 if (!buf_prevkey) 1898 return -ENOMEM; 1899 1900 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1901 if (!buf) { 1902 kvfree(buf_prevkey); 1903 return -ENOMEM; 1904 } 1905 1906 err = -EFAULT; 1907 prev_key = NULL; 1908 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1909 goto free_buf; 1910 key = buf; 1911 value = key + map->key_size; 1912 if (ubatch) 1913 prev_key = buf_prevkey; 1914 1915 for (cp = 0; cp < max_count;) { 1916 rcu_read_lock(); 1917 err = map->ops->map_get_next_key(map, prev_key, key); 1918 rcu_read_unlock(); 1919 if (err) 1920 break; 1921 err = bpf_map_copy_value(map, key, value, 1922 attr->batch.elem_flags); 1923 1924 if (err == -ENOENT) { 1925 if (retry) { 1926 retry--; 1927 continue; 1928 } 1929 err = -EINTR; 1930 break; 1931 } 1932 1933 if (err) 1934 goto free_buf; 1935 1936 if (copy_to_user(keys + cp * map->key_size, key, 1937 map->key_size)) { 1938 err = -EFAULT; 1939 goto free_buf; 1940 } 1941 if (copy_to_user(values + cp * value_size, value, value_size)) { 1942 err = -EFAULT; 1943 goto free_buf; 1944 } 1945 1946 if (!prev_key) 1947 prev_key = buf_prevkey; 1948 1949 swap(prev_key, key); 1950 retry = MAP_LOOKUP_RETRIES; 1951 cp++; 1952 cond_resched(); 1953 } 1954 1955 if (err == -EFAULT) 1956 goto free_buf; 1957 1958 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1959 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1960 err = -EFAULT; 1961 1962 free_buf: 1963 kvfree(buf_prevkey); 1964 kvfree(buf); 1965 return err; 1966 } 1967 1968 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 1969 1970 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1971 { 1972 void __user *ukey = u64_to_user_ptr(attr->key); 1973 void __user *uvalue = u64_to_user_ptr(attr->value); 1974 struct bpf_map *map; 1975 void *key, *value; 1976 u32 value_size; 1977 int err; 1978 1979 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 1980 return -EINVAL; 1981 1982 if (attr->flags & ~BPF_F_LOCK) 1983 return -EINVAL; 1984 1985 CLASS(fd, f)(attr->map_fd); 1986 map = __bpf_map_get(f); 1987 if (IS_ERR(map)) 1988 return PTR_ERR(map); 1989 bpf_map_write_active_inc(map); 1990 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 1991 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1992 err = -EPERM; 1993 goto err_put; 1994 } 1995 1996 if (attr->flags && 1997 (map->map_type == BPF_MAP_TYPE_QUEUE || 1998 map->map_type == BPF_MAP_TYPE_STACK)) { 1999 err = -EINVAL; 2000 goto err_put; 2001 } 2002 2003 if ((attr->flags & BPF_F_LOCK) && 2004 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2005 err = -EINVAL; 2006 goto err_put; 2007 } 2008 2009 key = __bpf_copy_key(ukey, map->key_size); 2010 if (IS_ERR(key)) { 2011 err = PTR_ERR(key); 2012 goto err_put; 2013 } 2014 2015 value_size = bpf_map_value_size(map); 2016 2017 err = -ENOMEM; 2018 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2019 if (!value) 2020 goto free_key; 2021 2022 err = -ENOTSUPP; 2023 if (map->map_type == BPF_MAP_TYPE_QUEUE || 2024 map->map_type == BPF_MAP_TYPE_STACK) { 2025 err = map->ops->map_pop_elem(map, value); 2026 } else if (map->map_type == BPF_MAP_TYPE_HASH || 2027 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 2028 map->map_type == BPF_MAP_TYPE_LRU_HASH || 2029 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 2030 if (!bpf_map_is_offloaded(map)) { 2031 bpf_disable_instrumentation(); 2032 rcu_read_lock(); 2033 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 2034 rcu_read_unlock(); 2035 bpf_enable_instrumentation(); 2036 } 2037 } 2038 2039 if (err) 2040 goto free_value; 2041 2042 if (copy_to_user(uvalue, value, value_size) != 0) { 2043 err = -EFAULT; 2044 goto free_value; 2045 } 2046 2047 err = 0; 2048 2049 free_value: 2050 kvfree(value); 2051 free_key: 2052 kvfree(key); 2053 err_put: 2054 bpf_map_write_active_dec(map); 2055 return err; 2056 } 2057 2058 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 2059 2060 static int map_freeze(const union bpf_attr *attr) 2061 { 2062 int err = 0; 2063 struct bpf_map *map; 2064 2065 if (CHECK_ATTR(BPF_MAP_FREEZE)) 2066 return -EINVAL; 2067 2068 CLASS(fd, f)(attr->map_fd); 2069 map = __bpf_map_get(f); 2070 if (IS_ERR(map)) 2071 return PTR_ERR(map); 2072 2073 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) 2074 return -ENOTSUPP; 2075 2076 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) 2077 return -EPERM; 2078 2079 mutex_lock(&map->freeze_mutex); 2080 if (bpf_map_write_active(map)) { 2081 err = -EBUSY; 2082 goto err_put; 2083 } 2084 if (READ_ONCE(map->frozen)) { 2085 err = -EBUSY; 2086 goto err_put; 2087 } 2088 2089 WRITE_ONCE(map->frozen, true); 2090 err_put: 2091 mutex_unlock(&map->freeze_mutex); 2092 return err; 2093 } 2094 2095 static const struct bpf_prog_ops * const bpf_prog_types[] = { 2096 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 2097 [_id] = & _name ## _prog_ops, 2098 #define BPF_MAP_TYPE(_id, _ops) 2099 #define BPF_LINK_TYPE(_id, _name) 2100 #include <linux/bpf_types.h> 2101 #undef BPF_PROG_TYPE 2102 #undef BPF_MAP_TYPE 2103 #undef BPF_LINK_TYPE 2104 }; 2105 2106 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 2107 { 2108 const struct bpf_prog_ops *ops; 2109 2110 if (type >= ARRAY_SIZE(bpf_prog_types)) 2111 return -EINVAL; 2112 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 2113 ops = bpf_prog_types[type]; 2114 if (!ops) 2115 return -EINVAL; 2116 2117 if (!bpf_prog_is_offloaded(prog->aux)) 2118 prog->aux->ops = ops; 2119 else 2120 prog->aux->ops = &bpf_offload_prog_ops; 2121 prog->type = type; 2122 return 0; 2123 } 2124 2125 enum bpf_audit { 2126 BPF_AUDIT_LOAD, 2127 BPF_AUDIT_UNLOAD, 2128 BPF_AUDIT_MAX, 2129 }; 2130 2131 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 2132 [BPF_AUDIT_LOAD] = "LOAD", 2133 [BPF_AUDIT_UNLOAD] = "UNLOAD", 2134 }; 2135 2136 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 2137 { 2138 struct audit_context *ctx = NULL; 2139 struct audit_buffer *ab; 2140 2141 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 2142 return; 2143 if (audit_enabled == AUDIT_OFF) 2144 return; 2145 if (!in_irq() && !irqs_disabled()) 2146 ctx = audit_context(); 2147 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 2148 if (unlikely(!ab)) 2149 return; 2150 audit_log_format(ab, "prog-id=%u op=%s", 2151 prog->aux->id, bpf_audit_str[op]); 2152 audit_log_end(ab); 2153 } 2154 2155 static int bpf_prog_alloc_id(struct bpf_prog *prog) 2156 { 2157 int id; 2158 2159 idr_preload(GFP_KERNEL); 2160 spin_lock_bh(&prog_idr_lock); 2161 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 2162 if (id > 0) 2163 prog->aux->id = id; 2164 spin_unlock_bh(&prog_idr_lock); 2165 idr_preload_end(); 2166 2167 /* id is in [1, INT_MAX) */ 2168 if (WARN_ON_ONCE(!id)) 2169 return -ENOSPC; 2170 2171 return id > 0 ? 0 : id; 2172 } 2173 2174 void bpf_prog_free_id(struct bpf_prog *prog) 2175 { 2176 unsigned long flags; 2177 2178 /* cBPF to eBPF migrations are currently not in the idr store. 2179 * Offloaded programs are removed from the store when their device 2180 * disappears - even if someone grabs an fd to them they are unusable, 2181 * simply waiting for refcnt to drop to be freed. 2182 */ 2183 if (!prog->aux->id) 2184 return; 2185 2186 spin_lock_irqsave(&prog_idr_lock, flags); 2187 idr_remove(&prog_idr, prog->aux->id); 2188 prog->aux->id = 0; 2189 spin_unlock_irqrestore(&prog_idr_lock, flags); 2190 } 2191 2192 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 2193 { 2194 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 2195 2196 kvfree(aux->func_info); 2197 kfree(aux->func_info_aux); 2198 free_uid(aux->user); 2199 security_bpf_prog_free(aux->prog); 2200 bpf_prog_free(aux->prog); 2201 } 2202 2203 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 2204 { 2205 bpf_prog_kallsyms_del_all(prog); 2206 btf_put(prog->aux->btf); 2207 module_put(prog->aux->mod); 2208 kvfree(prog->aux->jited_linfo); 2209 kvfree(prog->aux->linfo); 2210 kfree(prog->aux->kfunc_tab); 2211 if (prog->aux->attach_btf) 2212 btf_put(prog->aux->attach_btf); 2213 2214 if (deferred) { 2215 if (prog->sleepable) 2216 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 2217 else 2218 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 2219 } else { 2220 __bpf_prog_put_rcu(&prog->aux->rcu); 2221 } 2222 } 2223 2224 static void bpf_prog_put_deferred(struct work_struct *work) 2225 { 2226 struct bpf_prog_aux *aux; 2227 struct bpf_prog *prog; 2228 2229 aux = container_of(work, struct bpf_prog_aux, work); 2230 prog = aux->prog; 2231 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 2232 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 2233 bpf_prog_free_id(prog); 2234 __bpf_prog_put_noref(prog, true); 2235 } 2236 2237 static void __bpf_prog_put(struct bpf_prog *prog) 2238 { 2239 struct bpf_prog_aux *aux = prog->aux; 2240 2241 if (atomic64_dec_and_test(&aux->refcnt)) { 2242 if (in_irq() || irqs_disabled()) { 2243 INIT_WORK(&aux->work, bpf_prog_put_deferred); 2244 schedule_work(&aux->work); 2245 } else { 2246 bpf_prog_put_deferred(&aux->work); 2247 } 2248 } 2249 } 2250 2251 void bpf_prog_put(struct bpf_prog *prog) 2252 { 2253 __bpf_prog_put(prog); 2254 } 2255 EXPORT_SYMBOL_GPL(bpf_prog_put); 2256 2257 static int bpf_prog_release(struct inode *inode, struct file *filp) 2258 { 2259 struct bpf_prog *prog = filp->private_data; 2260 2261 bpf_prog_put(prog); 2262 return 0; 2263 } 2264 2265 struct bpf_prog_kstats { 2266 u64 nsecs; 2267 u64 cnt; 2268 u64 misses; 2269 }; 2270 2271 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) 2272 { 2273 struct bpf_prog_stats *stats; 2274 unsigned int flags; 2275 2276 stats = this_cpu_ptr(prog->stats); 2277 flags = u64_stats_update_begin_irqsave(&stats->syncp); 2278 u64_stats_inc(&stats->misses); 2279 u64_stats_update_end_irqrestore(&stats->syncp, flags); 2280 } 2281 2282 static void bpf_prog_get_stats(const struct bpf_prog *prog, 2283 struct bpf_prog_kstats *stats) 2284 { 2285 u64 nsecs = 0, cnt = 0, misses = 0; 2286 int cpu; 2287 2288 for_each_possible_cpu(cpu) { 2289 const struct bpf_prog_stats *st; 2290 unsigned int start; 2291 u64 tnsecs, tcnt, tmisses; 2292 2293 st = per_cpu_ptr(prog->stats, cpu); 2294 do { 2295 start = u64_stats_fetch_begin(&st->syncp); 2296 tnsecs = u64_stats_read(&st->nsecs); 2297 tcnt = u64_stats_read(&st->cnt); 2298 tmisses = u64_stats_read(&st->misses); 2299 } while (u64_stats_fetch_retry(&st->syncp, start)); 2300 nsecs += tnsecs; 2301 cnt += tcnt; 2302 misses += tmisses; 2303 } 2304 stats->nsecs = nsecs; 2305 stats->cnt = cnt; 2306 stats->misses = misses; 2307 } 2308 2309 #ifdef CONFIG_PROC_FS 2310 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 2311 { 2312 const struct bpf_prog *prog = filp->private_data; 2313 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2314 struct bpf_prog_kstats stats; 2315 2316 bpf_prog_get_stats(prog, &stats); 2317 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2318 seq_printf(m, 2319 "prog_type:\t%u\n" 2320 "prog_jited:\t%u\n" 2321 "prog_tag:\t%s\n" 2322 "memlock:\t%llu\n" 2323 "prog_id:\t%u\n" 2324 "run_time_ns:\t%llu\n" 2325 "run_cnt:\t%llu\n" 2326 "recursion_misses:\t%llu\n" 2327 "verified_insns:\t%u\n", 2328 prog->type, 2329 prog->jited, 2330 prog_tag, 2331 prog->pages * 1ULL << PAGE_SHIFT, 2332 prog->aux->id, 2333 stats.nsecs, 2334 stats.cnt, 2335 stats.misses, 2336 prog->aux->verified_insns); 2337 } 2338 #endif 2339 2340 const struct file_operations bpf_prog_fops = { 2341 #ifdef CONFIG_PROC_FS 2342 .show_fdinfo = bpf_prog_show_fdinfo, 2343 #endif 2344 .release = bpf_prog_release, 2345 .read = bpf_dummy_read, 2346 .write = bpf_dummy_write, 2347 }; 2348 2349 int bpf_prog_new_fd(struct bpf_prog *prog) 2350 { 2351 int ret; 2352 2353 ret = security_bpf_prog(prog); 2354 if (ret < 0) 2355 return ret; 2356 2357 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 2358 O_RDWR | O_CLOEXEC); 2359 } 2360 2361 void bpf_prog_add(struct bpf_prog *prog, int i) 2362 { 2363 atomic64_add(i, &prog->aux->refcnt); 2364 } 2365 EXPORT_SYMBOL_GPL(bpf_prog_add); 2366 2367 void bpf_prog_sub(struct bpf_prog *prog, int i) 2368 { 2369 /* Only to be used for undoing previous bpf_prog_add() in some 2370 * error path. We still know that another entity in our call 2371 * path holds a reference to the program, thus atomic_sub() can 2372 * be safely used in such cases! 2373 */ 2374 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 2375 } 2376 EXPORT_SYMBOL_GPL(bpf_prog_sub); 2377 2378 void bpf_prog_inc(struct bpf_prog *prog) 2379 { 2380 atomic64_inc(&prog->aux->refcnt); 2381 } 2382 EXPORT_SYMBOL_GPL(bpf_prog_inc); 2383 2384 /* prog_idr_lock should have been held */ 2385 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 2386 { 2387 int refold; 2388 2389 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 2390 2391 if (!refold) 2392 return ERR_PTR(-ENOENT); 2393 2394 return prog; 2395 } 2396 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 2397 2398 bool bpf_prog_get_ok(struct bpf_prog *prog, 2399 enum bpf_prog_type *attach_type, bool attach_drv) 2400 { 2401 /* not an attachment, just a refcount inc, always allow */ 2402 if (!attach_type) 2403 return true; 2404 2405 if (prog->type != *attach_type) 2406 return false; 2407 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) 2408 return false; 2409 2410 return true; 2411 } 2412 2413 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 2414 bool attach_drv) 2415 { 2416 CLASS(fd, f)(ufd); 2417 struct bpf_prog *prog; 2418 2419 if (fd_empty(f)) 2420 return ERR_PTR(-EBADF); 2421 if (fd_file(f)->f_op != &bpf_prog_fops) 2422 return ERR_PTR(-EINVAL); 2423 2424 prog = fd_file(f)->private_data; 2425 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) 2426 return ERR_PTR(-EINVAL); 2427 2428 bpf_prog_inc(prog); 2429 return prog; 2430 } 2431 2432 struct bpf_prog *bpf_prog_get(u32 ufd) 2433 { 2434 return __bpf_prog_get(ufd, NULL, false); 2435 } 2436 2437 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2438 bool attach_drv) 2439 { 2440 return __bpf_prog_get(ufd, &type, attach_drv); 2441 } 2442 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2443 2444 /* Initially all BPF programs could be loaded w/o specifying 2445 * expected_attach_type. Later for some of them specifying expected_attach_type 2446 * at load time became required so that program could be validated properly. 2447 * Programs of types that are allowed to be loaded both w/ and w/o (for 2448 * backward compatibility) expected_attach_type, should have the default attach 2449 * type assigned to expected_attach_type for the latter case, so that it can be 2450 * validated later at attach time. 2451 * 2452 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2453 * prog type requires it but has some attach types that have to be backward 2454 * compatible. 2455 */ 2456 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2457 { 2458 switch (attr->prog_type) { 2459 case BPF_PROG_TYPE_CGROUP_SOCK: 2460 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2461 * exist so checking for non-zero is the way to go here. 2462 */ 2463 if (!attr->expected_attach_type) 2464 attr->expected_attach_type = 2465 BPF_CGROUP_INET_SOCK_CREATE; 2466 break; 2467 case BPF_PROG_TYPE_SK_REUSEPORT: 2468 if (!attr->expected_attach_type) 2469 attr->expected_attach_type = 2470 BPF_SK_REUSEPORT_SELECT; 2471 break; 2472 } 2473 } 2474 2475 static int 2476 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2477 enum bpf_attach_type expected_attach_type, 2478 struct btf *attach_btf, u32 btf_id, 2479 struct bpf_prog *dst_prog) 2480 { 2481 if (btf_id) { 2482 if (btf_id > BTF_MAX_TYPE) 2483 return -EINVAL; 2484 2485 if (!attach_btf && !dst_prog) 2486 return -EINVAL; 2487 2488 switch (prog_type) { 2489 case BPF_PROG_TYPE_TRACING: 2490 case BPF_PROG_TYPE_LSM: 2491 case BPF_PROG_TYPE_STRUCT_OPS: 2492 case BPF_PROG_TYPE_EXT: 2493 break; 2494 default: 2495 return -EINVAL; 2496 } 2497 } 2498 2499 if (attach_btf && (!btf_id || dst_prog)) 2500 return -EINVAL; 2501 2502 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2503 prog_type != BPF_PROG_TYPE_EXT) 2504 return -EINVAL; 2505 2506 switch (prog_type) { 2507 case BPF_PROG_TYPE_CGROUP_SOCK: 2508 switch (expected_attach_type) { 2509 case BPF_CGROUP_INET_SOCK_CREATE: 2510 case BPF_CGROUP_INET_SOCK_RELEASE: 2511 case BPF_CGROUP_INET4_POST_BIND: 2512 case BPF_CGROUP_INET6_POST_BIND: 2513 return 0; 2514 default: 2515 return -EINVAL; 2516 } 2517 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2518 switch (expected_attach_type) { 2519 case BPF_CGROUP_INET4_BIND: 2520 case BPF_CGROUP_INET6_BIND: 2521 case BPF_CGROUP_INET4_CONNECT: 2522 case BPF_CGROUP_INET6_CONNECT: 2523 case BPF_CGROUP_UNIX_CONNECT: 2524 case BPF_CGROUP_INET4_GETPEERNAME: 2525 case BPF_CGROUP_INET6_GETPEERNAME: 2526 case BPF_CGROUP_UNIX_GETPEERNAME: 2527 case BPF_CGROUP_INET4_GETSOCKNAME: 2528 case BPF_CGROUP_INET6_GETSOCKNAME: 2529 case BPF_CGROUP_UNIX_GETSOCKNAME: 2530 case BPF_CGROUP_UDP4_SENDMSG: 2531 case BPF_CGROUP_UDP6_SENDMSG: 2532 case BPF_CGROUP_UNIX_SENDMSG: 2533 case BPF_CGROUP_UDP4_RECVMSG: 2534 case BPF_CGROUP_UDP6_RECVMSG: 2535 case BPF_CGROUP_UNIX_RECVMSG: 2536 return 0; 2537 default: 2538 return -EINVAL; 2539 } 2540 case BPF_PROG_TYPE_CGROUP_SKB: 2541 switch (expected_attach_type) { 2542 case BPF_CGROUP_INET_INGRESS: 2543 case BPF_CGROUP_INET_EGRESS: 2544 return 0; 2545 default: 2546 return -EINVAL; 2547 } 2548 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2549 switch (expected_attach_type) { 2550 case BPF_CGROUP_SETSOCKOPT: 2551 case BPF_CGROUP_GETSOCKOPT: 2552 return 0; 2553 default: 2554 return -EINVAL; 2555 } 2556 case BPF_PROG_TYPE_SK_LOOKUP: 2557 if (expected_attach_type == BPF_SK_LOOKUP) 2558 return 0; 2559 return -EINVAL; 2560 case BPF_PROG_TYPE_SK_REUSEPORT: 2561 switch (expected_attach_type) { 2562 case BPF_SK_REUSEPORT_SELECT: 2563 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2564 return 0; 2565 default: 2566 return -EINVAL; 2567 } 2568 case BPF_PROG_TYPE_NETFILTER: 2569 if (expected_attach_type == BPF_NETFILTER) 2570 return 0; 2571 return -EINVAL; 2572 case BPF_PROG_TYPE_SYSCALL: 2573 case BPF_PROG_TYPE_EXT: 2574 if (expected_attach_type) 2575 return -EINVAL; 2576 fallthrough; 2577 default: 2578 return 0; 2579 } 2580 } 2581 2582 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2583 { 2584 switch (prog_type) { 2585 case BPF_PROG_TYPE_SCHED_CLS: 2586 case BPF_PROG_TYPE_SCHED_ACT: 2587 case BPF_PROG_TYPE_XDP: 2588 case BPF_PROG_TYPE_LWT_IN: 2589 case BPF_PROG_TYPE_LWT_OUT: 2590 case BPF_PROG_TYPE_LWT_XMIT: 2591 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2592 case BPF_PROG_TYPE_SK_SKB: 2593 case BPF_PROG_TYPE_SK_MSG: 2594 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2595 case BPF_PROG_TYPE_CGROUP_DEVICE: 2596 case BPF_PROG_TYPE_CGROUP_SOCK: 2597 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2598 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2599 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2600 case BPF_PROG_TYPE_SOCK_OPS: 2601 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2602 case BPF_PROG_TYPE_NETFILTER: 2603 return true; 2604 case BPF_PROG_TYPE_CGROUP_SKB: 2605 /* always unpriv */ 2606 case BPF_PROG_TYPE_SK_REUSEPORT: 2607 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2608 default: 2609 return false; 2610 } 2611 } 2612 2613 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2614 { 2615 switch (prog_type) { 2616 case BPF_PROG_TYPE_KPROBE: 2617 case BPF_PROG_TYPE_TRACEPOINT: 2618 case BPF_PROG_TYPE_PERF_EVENT: 2619 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2620 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2621 case BPF_PROG_TYPE_TRACING: 2622 case BPF_PROG_TYPE_LSM: 2623 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2624 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2625 return true; 2626 default: 2627 return false; 2628 } 2629 } 2630 2631 /* last field in 'union bpf_attr' used by this command */ 2632 #define BPF_PROG_LOAD_LAST_FIELD prog_token_fd 2633 2634 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) 2635 { 2636 enum bpf_prog_type type = attr->prog_type; 2637 struct bpf_prog *prog, *dst_prog = NULL; 2638 struct btf *attach_btf = NULL; 2639 struct bpf_token *token = NULL; 2640 bool bpf_cap; 2641 int err; 2642 char license[128]; 2643 2644 if (CHECK_ATTR(BPF_PROG_LOAD)) 2645 return -EINVAL; 2646 2647 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2648 BPF_F_ANY_ALIGNMENT | 2649 BPF_F_TEST_STATE_FREQ | 2650 BPF_F_SLEEPABLE | 2651 BPF_F_TEST_RND_HI32 | 2652 BPF_F_XDP_HAS_FRAGS | 2653 BPF_F_XDP_DEV_BOUND_ONLY | 2654 BPF_F_TEST_REG_INVARIANTS | 2655 BPF_F_TOKEN_FD)) 2656 return -EINVAL; 2657 2658 bpf_prog_load_fixup_attach_type(attr); 2659 2660 if (attr->prog_flags & BPF_F_TOKEN_FD) { 2661 token = bpf_token_get_from_fd(attr->prog_token_fd); 2662 if (IS_ERR(token)) 2663 return PTR_ERR(token); 2664 /* if current token doesn't grant prog loading permissions, 2665 * then we can't use this token, so ignore it and rely on 2666 * system-wide capabilities checks 2667 */ 2668 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || 2669 !bpf_token_allow_prog_type(token, attr->prog_type, 2670 attr->expected_attach_type)) { 2671 bpf_token_put(token); 2672 token = NULL; 2673 } 2674 } 2675 2676 bpf_cap = bpf_token_capable(token, CAP_BPF); 2677 err = -EPERM; 2678 2679 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2680 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2681 !bpf_cap) 2682 goto put_token; 2683 2684 /* Intent here is for unprivileged_bpf_disabled to block BPF program 2685 * creation for unprivileged users; other actions depend 2686 * on fd availability and access to bpffs, so are dependent on 2687 * object creation success. Even with unprivileged BPF disabled, 2688 * capability checks are still carried out for these 2689 * and other operations. 2690 */ 2691 if (sysctl_unprivileged_bpf_disabled && !bpf_cap) 2692 goto put_token; 2693 2694 if (attr->insn_cnt == 0 || 2695 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { 2696 err = -E2BIG; 2697 goto put_token; 2698 } 2699 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2700 type != BPF_PROG_TYPE_CGROUP_SKB && 2701 !bpf_cap) 2702 goto put_token; 2703 2704 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) 2705 goto put_token; 2706 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) 2707 goto put_token; 2708 2709 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2710 * or btf, we need to check which one it is 2711 */ 2712 if (attr->attach_prog_fd) { 2713 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2714 if (IS_ERR(dst_prog)) { 2715 dst_prog = NULL; 2716 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2717 if (IS_ERR(attach_btf)) { 2718 err = -EINVAL; 2719 goto put_token; 2720 } 2721 if (!btf_is_kernel(attach_btf)) { 2722 /* attaching through specifying bpf_prog's BTF 2723 * objects directly might be supported eventually 2724 */ 2725 btf_put(attach_btf); 2726 err = -ENOTSUPP; 2727 goto put_token; 2728 } 2729 } 2730 } else if (attr->attach_btf_id) { 2731 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2732 attach_btf = bpf_get_btf_vmlinux(); 2733 if (IS_ERR(attach_btf)) { 2734 err = PTR_ERR(attach_btf); 2735 goto put_token; 2736 } 2737 if (!attach_btf) { 2738 err = -EINVAL; 2739 goto put_token; 2740 } 2741 btf_get(attach_btf); 2742 } 2743 2744 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2745 attach_btf, attr->attach_btf_id, 2746 dst_prog)) { 2747 if (dst_prog) 2748 bpf_prog_put(dst_prog); 2749 if (attach_btf) 2750 btf_put(attach_btf); 2751 err = -EINVAL; 2752 goto put_token; 2753 } 2754 2755 /* plain bpf_prog allocation */ 2756 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2757 if (!prog) { 2758 if (dst_prog) 2759 bpf_prog_put(dst_prog); 2760 if (attach_btf) 2761 btf_put(attach_btf); 2762 err = -EINVAL; 2763 goto put_token; 2764 } 2765 2766 prog->expected_attach_type = attr->expected_attach_type; 2767 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); 2768 prog->aux->attach_btf = attach_btf; 2769 prog->aux->attach_btf_id = attr->attach_btf_id; 2770 prog->aux->dst_prog = dst_prog; 2771 prog->aux->dev_bound = !!attr->prog_ifindex; 2772 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 2773 2774 /* move token into prog->aux, reuse taken refcnt */ 2775 prog->aux->token = token; 2776 token = NULL; 2777 2778 prog->aux->user = get_current_user(); 2779 prog->len = attr->insn_cnt; 2780 2781 err = -EFAULT; 2782 if (copy_from_bpfptr(prog->insns, 2783 make_bpfptr(attr->insns, uattr.is_kernel), 2784 bpf_prog_insn_size(prog)) != 0) 2785 goto free_prog; 2786 /* copy eBPF program license from user space */ 2787 if (strncpy_from_bpfptr(license, 2788 make_bpfptr(attr->license, uattr.is_kernel), 2789 sizeof(license) - 1) < 0) 2790 goto free_prog; 2791 license[sizeof(license) - 1] = 0; 2792 2793 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2794 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; 2795 2796 prog->orig_prog = NULL; 2797 prog->jited = 0; 2798 2799 atomic64_set(&prog->aux->refcnt, 1); 2800 2801 if (bpf_prog_is_dev_bound(prog->aux)) { 2802 err = bpf_prog_dev_bound_init(prog, attr); 2803 if (err) 2804 goto free_prog; 2805 } 2806 2807 if (type == BPF_PROG_TYPE_EXT && dst_prog && 2808 bpf_prog_is_dev_bound(dst_prog->aux)) { 2809 err = bpf_prog_dev_bound_inherit(prog, dst_prog); 2810 if (err) 2811 goto free_prog; 2812 } 2813 2814 /* 2815 * Bookkeeping for managing the program attachment chain. 2816 * 2817 * It might be tempting to set attach_tracing_prog flag at the attachment 2818 * time, but this will not prevent from loading bunch of tracing prog 2819 * first, then attach them one to another. 2820 * 2821 * The flag attach_tracing_prog is set for the whole program lifecycle, and 2822 * doesn't have to be cleared in bpf_tracing_link_release, since tracing 2823 * programs cannot change attachment target. 2824 */ 2825 if (type == BPF_PROG_TYPE_TRACING && dst_prog && 2826 dst_prog->type == BPF_PROG_TYPE_TRACING) { 2827 prog->aux->attach_tracing_prog = true; 2828 } 2829 2830 /* find program type: socket_filter vs tracing_filter */ 2831 err = find_prog_type(type, prog); 2832 if (err < 0) 2833 goto free_prog; 2834 2835 prog->aux->load_time = ktime_get_boottime_ns(); 2836 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2837 sizeof(attr->prog_name)); 2838 if (err < 0) 2839 goto free_prog; 2840 2841 err = security_bpf_prog_load(prog, attr, token); 2842 if (err) 2843 goto free_prog_sec; 2844 2845 /* run eBPF verifier */ 2846 err = bpf_check(&prog, attr, uattr, uattr_size); 2847 if (err < 0) 2848 goto free_used_maps; 2849 2850 prog = bpf_prog_select_runtime(prog, &err); 2851 if (err < 0) 2852 goto free_used_maps; 2853 2854 err = bpf_prog_alloc_id(prog); 2855 if (err) 2856 goto free_used_maps; 2857 2858 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2859 * effectively publicly exposed. However, retrieving via 2860 * bpf_prog_get_fd_by_id() will take another reference, 2861 * therefore it cannot be gone underneath us. 2862 * 2863 * Only for the time /after/ successful bpf_prog_new_fd() 2864 * and before returning to userspace, we might just hold 2865 * one reference and any parallel close on that fd could 2866 * rip everything out. Hence, below notifications must 2867 * happen before bpf_prog_new_fd(). 2868 * 2869 * Also, any failure handling from this point onwards must 2870 * be using bpf_prog_put() given the program is exposed. 2871 */ 2872 bpf_prog_kallsyms_add(prog); 2873 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2874 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2875 2876 err = bpf_prog_new_fd(prog); 2877 if (err < 0) 2878 bpf_prog_put(prog); 2879 return err; 2880 2881 free_used_maps: 2882 /* In case we have subprogs, we need to wait for a grace 2883 * period before we can tear down JIT memory since symbols 2884 * are already exposed under kallsyms. 2885 */ 2886 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); 2887 return err; 2888 2889 free_prog_sec: 2890 security_bpf_prog_free(prog); 2891 free_prog: 2892 free_uid(prog->aux->user); 2893 if (prog->aux->attach_btf) 2894 btf_put(prog->aux->attach_btf); 2895 bpf_prog_free(prog); 2896 put_token: 2897 bpf_token_put(token); 2898 return err; 2899 } 2900 2901 #define BPF_OBJ_LAST_FIELD path_fd 2902 2903 static int bpf_obj_pin(const union bpf_attr *attr) 2904 { 2905 int path_fd; 2906 2907 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) 2908 return -EINVAL; 2909 2910 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 2911 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 2912 return -EINVAL; 2913 2914 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 2915 return bpf_obj_pin_user(attr->bpf_fd, path_fd, 2916 u64_to_user_ptr(attr->pathname)); 2917 } 2918 2919 static int bpf_obj_get(const union bpf_attr *attr) 2920 { 2921 int path_fd; 2922 2923 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2924 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) 2925 return -EINVAL; 2926 2927 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 2928 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 2929 return -EINVAL; 2930 2931 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 2932 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), 2933 attr->file_flags); 2934 } 2935 2936 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2937 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2938 { 2939 WARN_ON(ops->dealloc && ops->dealloc_deferred); 2940 atomic64_set(&link->refcnt, 1); 2941 link->type = type; 2942 link->id = 0; 2943 link->ops = ops; 2944 link->prog = prog; 2945 } 2946 2947 static void bpf_link_free_id(int id) 2948 { 2949 if (!id) 2950 return; 2951 2952 spin_lock_bh(&link_idr_lock); 2953 idr_remove(&link_idr, id); 2954 spin_unlock_bh(&link_idr_lock); 2955 } 2956 2957 /* Clean up bpf_link and corresponding anon_inode file and FD. After 2958 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 2959 * anon_inode's release() call. This helper marks bpf_link as 2960 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 2961 * is not decremented, it's the responsibility of a calling code that failed 2962 * to complete bpf_link initialization. 2963 * This helper eventually calls link's dealloc callback, but does not call 2964 * link's release callback. 2965 */ 2966 void bpf_link_cleanup(struct bpf_link_primer *primer) 2967 { 2968 primer->link->prog = NULL; 2969 bpf_link_free_id(primer->id); 2970 fput(primer->file); 2971 put_unused_fd(primer->fd); 2972 } 2973 2974 void bpf_link_inc(struct bpf_link *link) 2975 { 2976 atomic64_inc(&link->refcnt); 2977 } 2978 2979 static void bpf_link_dealloc(struct bpf_link *link) 2980 { 2981 /* now that we know that bpf_link itself can't be reached, put underlying BPF program */ 2982 if (link->prog) 2983 bpf_prog_put(link->prog); 2984 2985 /* free bpf_link and its containing memory */ 2986 if (link->ops->dealloc_deferred) 2987 link->ops->dealloc_deferred(link); 2988 else 2989 link->ops->dealloc(link); 2990 } 2991 2992 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) 2993 { 2994 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); 2995 2996 bpf_link_dealloc(link); 2997 } 2998 2999 static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu) 3000 { 3001 if (rcu_trace_implies_rcu_gp()) 3002 bpf_link_defer_dealloc_rcu_gp(rcu); 3003 else 3004 call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp); 3005 } 3006 3007 /* bpf_link_free is guaranteed to be called from process context */ 3008 static void bpf_link_free(struct bpf_link *link) 3009 { 3010 const struct bpf_link_ops *ops = link->ops; 3011 bool sleepable = false; 3012 3013 bpf_link_free_id(link->id); 3014 if (link->prog) { 3015 sleepable = link->prog->sleepable; 3016 /* detach BPF program, clean up used resources */ 3017 ops->release(link); 3018 } 3019 if (ops->dealloc_deferred) { 3020 /* schedule BPF link deallocation; if underlying BPF program 3021 * is sleepable, we need to first wait for RCU tasks trace 3022 * sync, then go through "classic" RCU grace period 3023 */ 3024 if (sleepable) 3025 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp); 3026 else 3027 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3028 } else if (ops->dealloc) { 3029 bpf_link_dealloc(link); 3030 } 3031 } 3032 3033 static void bpf_link_put_deferred(struct work_struct *work) 3034 { 3035 struct bpf_link *link = container_of(work, struct bpf_link, work); 3036 3037 bpf_link_free(link); 3038 } 3039 3040 /* bpf_link_put might be called from atomic context. It needs to be called 3041 * from sleepable context in order to acquire sleeping locks during the process. 3042 */ 3043 void bpf_link_put(struct bpf_link *link) 3044 { 3045 if (!atomic64_dec_and_test(&link->refcnt)) 3046 return; 3047 3048 INIT_WORK(&link->work, bpf_link_put_deferred); 3049 schedule_work(&link->work); 3050 } 3051 EXPORT_SYMBOL(bpf_link_put); 3052 3053 static void bpf_link_put_direct(struct bpf_link *link) 3054 { 3055 if (!atomic64_dec_and_test(&link->refcnt)) 3056 return; 3057 bpf_link_free(link); 3058 } 3059 3060 static int bpf_link_release(struct inode *inode, struct file *filp) 3061 { 3062 struct bpf_link *link = filp->private_data; 3063 3064 bpf_link_put_direct(link); 3065 return 0; 3066 } 3067 3068 #ifdef CONFIG_PROC_FS 3069 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 3070 #define BPF_MAP_TYPE(_id, _ops) 3071 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 3072 static const char *bpf_link_type_strs[] = { 3073 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 3074 #include <linux/bpf_types.h> 3075 }; 3076 #undef BPF_PROG_TYPE 3077 #undef BPF_MAP_TYPE 3078 #undef BPF_LINK_TYPE 3079 3080 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 3081 { 3082 const struct bpf_link *link = filp->private_data; 3083 const struct bpf_prog *prog = link->prog; 3084 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 3085 3086 seq_printf(m, 3087 "link_type:\t%s\n" 3088 "link_id:\t%u\n", 3089 bpf_link_type_strs[link->type], 3090 link->id); 3091 if (prog) { 3092 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 3093 seq_printf(m, 3094 "prog_tag:\t%s\n" 3095 "prog_id:\t%u\n", 3096 prog_tag, 3097 prog->aux->id); 3098 } 3099 if (link->ops->show_fdinfo) 3100 link->ops->show_fdinfo(link, m); 3101 } 3102 #endif 3103 3104 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts) 3105 { 3106 struct bpf_link *link = file->private_data; 3107 3108 return link->ops->poll(file, pts); 3109 } 3110 3111 static const struct file_operations bpf_link_fops = { 3112 #ifdef CONFIG_PROC_FS 3113 .show_fdinfo = bpf_link_show_fdinfo, 3114 #endif 3115 .release = bpf_link_release, 3116 .read = bpf_dummy_read, 3117 .write = bpf_dummy_write, 3118 }; 3119 3120 static const struct file_operations bpf_link_fops_poll = { 3121 #ifdef CONFIG_PROC_FS 3122 .show_fdinfo = bpf_link_show_fdinfo, 3123 #endif 3124 .release = bpf_link_release, 3125 .read = bpf_dummy_read, 3126 .write = bpf_dummy_write, 3127 .poll = bpf_link_poll, 3128 }; 3129 3130 static int bpf_link_alloc_id(struct bpf_link *link) 3131 { 3132 int id; 3133 3134 idr_preload(GFP_KERNEL); 3135 spin_lock_bh(&link_idr_lock); 3136 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 3137 spin_unlock_bh(&link_idr_lock); 3138 idr_preload_end(); 3139 3140 return id; 3141 } 3142 3143 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 3144 * reserving unused FD and allocating ID from link_idr. This is to be paired 3145 * with bpf_link_settle() to install FD and ID and expose bpf_link to 3146 * user-space, if bpf_link is successfully attached. If not, bpf_link and 3147 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 3148 * transient state is passed around in struct bpf_link_primer. 3149 * This is preferred way to create and initialize bpf_link, especially when 3150 * there are complicated and expensive operations in between creating bpf_link 3151 * itself and attaching it to BPF hook. By using bpf_link_prime() and 3152 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 3153 * expensive (and potentially failing) roll back operations in a rare case 3154 * that file, FD, or ID can't be allocated. 3155 */ 3156 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 3157 { 3158 struct file *file; 3159 int fd, id; 3160 3161 fd = get_unused_fd_flags(O_CLOEXEC); 3162 if (fd < 0) 3163 return fd; 3164 3165 3166 id = bpf_link_alloc_id(link); 3167 if (id < 0) { 3168 put_unused_fd(fd); 3169 return id; 3170 } 3171 3172 file = anon_inode_getfile("bpf_link", 3173 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3174 link, O_CLOEXEC); 3175 if (IS_ERR(file)) { 3176 bpf_link_free_id(id); 3177 put_unused_fd(fd); 3178 return PTR_ERR(file); 3179 } 3180 3181 primer->link = link; 3182 primer->file = file; 3183 primer->fd = fd; 3184 primer->id = id; 3185 return 0; 3186 } 3187 3188 int bpf_link_settle(struct bpf_link_primer *primer) 3189 { 3190 /* make bpf_link fetchable by ID */ 3191 spin_lock_bh(&link_idr_lock); 3192 primer->link->id = primer->id; 3193 spin_unlock_bh(&link_idr_lock); 3194 /* make bpf_link fetchable by FD */ 3195 fd_install(primer->fd, primer->file); 3196 /* pass through installed FD */ 3197 return primer->fd; 3198 } 3199 3200 int bpf_link_new_fd(struct bpf_link *link) 3201 { 3202 return anon_inode_getfd("bpf-link", 3203 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3204 link, O_CLOEXEC); 3205 } 3206 3207 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 3208 { 3209 CLASS(fd, f)(ufd); 3210 struct bpf_link *link; 3211 3212 if (fd_empty(f)) 3213 return ERR_PTR(-EBADF); 3214 if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll) 3215 return ERR_PTR(-EINVAL); 3216 3217 link = fd_file(f)->private_data; 3218 bpf_link_inc(link); 3219 return link; 3220 } 3221 EXPORT_SYMBOL(bpf_link_get_from_fd); 3222 3223 static void bpf_tracing_link_release(struct bpf_link *link) 3224 { 3225 struct bpf_tracing_link *tr_link = 3226 container_of(link, struct bpf_tracing_link, link.link); 3227 3228 WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, 3229 tr_link->trampoline)); 3230 3231 bpf_trampoline_put(tr_link->trampoline); 3232 3233 /* tgt_prog is NULL if target is a kernel function */ 3234 if (tr_link->tgt_prog) 3235 bpf_prog_put(tr_link->tgt_prog); 3236 } 3237 3238 static void bpf_tracing_link_dealloc(struct bpf_link *link) 3239 { 3240 struct bpf_tracing_link *tr_link = 3241 container_of(link, struct bpf_tracing_link, link.link); 3242 3243 kfree(tr_link); 3244 } 3245 3246 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 3247 struct seq_file *seq) 3248 { 3249 struct bpf_tracing_link *tr_link = 3250 container_of(link, struct bpf_tracing_link, link.link); 3251 u32 target_btf_id, target_obj_id; 3252 3253 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3254 &target_obj_id, &target_btf_id); 3255 seq_printf(seq, 3256 "attach_type:\t%d\n" 3257 "target_obj_id:\t%u\n" 3258 "target_btf_id:\t%u\n", 3259 tr_link->attach_type, 3260 target_obj_id, 3261 target_btf_id); 3262 } 3263 3264 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 3265 struct bpf_link_info *info) 3266 { 3267 struct bpf_tracing_link *tr_link = 3268 container_of(link, struct bpf_tracing_link, link.link); 3269 3270 info->tracing.attach_type = tr_link->attach_type; 3271 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3272 &info->tracing.target_obj_id, 3273 &info->tracing.target_btf_id); 3274 3275 return 0; 3276 } 3277 3278 static const struct bpf_link_ops bpf_tracing_link_lops = { 3279 .release = bpf_tracing_link_release, 3280 .dealloc = bpf_tracing_link_dealloc, 3281 .show_fdinfo = bpf_tracing_link_show_fdinfo, 3282 .fill_link_info = bpf_tracing_link_fill_link_info, 3283 }; 3284 3285 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 3286 int tgt_prog_fd, 3287 u32 btf_id, 3288 u64 bpf_cookie) 3289 { 3290 struct bpf_link_primer link_primer; 3291 struct bpf_prog *tgt_prog = NULL; 3292 struct bpf_trampoline *tr = NULL; 3293 struct bpf_tracing_link *link; 3294 u64 key = 0; 3295 int err; 3296 3297 switch (prog->type) { 3298 case BPF_PROG_TYPE_TRACING: 3299 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 3300 prog->expected_attach_type != BPF_TRACE_FEXIT && 3301 prog->expected_attach_type != BPF_MODIFY_RETURN) { 3302 err = -EINVAL; 3303 goto out_put_prog; 3304 } 3305 break; 3306 case BPF_PROG_TYPE_EXT: 3307 if (prog->expected_attach_type != 0) { 3308 err = -EINVAL; 3309 goto out_put_prog; 3310 } 3311 break; 3312 case BPF_PROG_TYPE_LSM: 3313 if (prog->expected_attach_type != BPF_LSM_MAC) { 3314 err = -EINVAL; 3315 goto out_put_prog; 3316 } 3317 break; 3318 default: 3319 err = -EINVAL; 3320 goto out_put_prog; 3321 } 3322 3323 if (!!tgt_prog_fd != !!btf_id) { 3324 err = -EINVAL; 3325 goto out_put_prog; 3326 } 3327 3328 if (tgt_prog_fd) { 3329 /* 3330 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this 3331 * part would be changed to implement the same for 3332 * BPF_PROG_TYPE_TRACING, do not forget to update the way how 3333 * attach_tracing_prog flag is set. 3334 */ 3335 if (prog->type != BPF_PROG_TYPE_EXT) { 3336 err = -EINVAL; 3337 goto out_put_prog; 3338 } 3339 3340 tgt_prog = bpf_prog_get(tgt_prog_fd); 3341 if (IS_ERR(tgt_prog)) { 3342 err = PTR_ERR(tgt_prog); 3343 tgt_prog = NULL; 3344 goto out_put_prog; 3345 } 3346 3347 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 3348 } 3349 3350 link = kzalloc(sizeof(*link), GFP_USER); 3351 if (!link) { 3352 err = -ENOMEM; 3353 goto out_put_prog; 3354 } 3355 bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, 3356 &bpf_tracing_link_lops, prog); 3357 link->attach_type = prog->expected_attach_type; 3358 link->link.cookie = bpf_cookie; 3359 3360 mutex_lock(&prog->aux->dst_mutex); 3361 3362 /* There are a few possible cases here: 3363 * 3364 * - if prog->aux->dst_trampoline is set, the program was just loaded 3365 * and not yet attached to anything, so we can use the values stored 3366 * in prog->aux 3367 * 3368 * - if prog->aux->dst_trampoline is NULL, the program has already been 3369 * attached to a target and its initial target was cleared (below) 3370 * 3371 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 3372 * target_btf_id using the link_create API. 3373 * 3374 * - if tgt_prog == NULL when this function was called using the old 3375 * raw_tracepoint_open API, and we need a target from prog->aux 3376 * 3377 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 3378 * was detached and is going for re-attachment. 3379 * 3380 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf 3381 * are NULL, then program was already attached and user did not provide 3382 * tgt_prog_fd so we have no way to find out or create trampoline 3383 */ 3384 if (!prog->aux->dst_trampoline && !tgt_prog) { 3385 /* 3386 * Allow re-attach for TRACING and LSM programs. If it's 3387 * currently linked, bpf_trampoline_link_prog will fail. 3388 * EXT programs need to specify tgt_prog_fd, so they 3389 * re-attach in separate code path. 3390 */ 3391 if (prog->type != BPF_PROG_TYPE_TRACING && 3392 prog->type != BPF_PROG_TYPE_LSM) { 3393 err = -EINVAL; 3394 goto out_unlock; 3395 } 3396 /* We can allow re-attach only if we have valid attach_btf. */ 3397 if (!prog->aux->attach_btf) { 3398 err = -EINVAL; 3399 goto out_unlock; 3400 } 3401 btf_id = prog->aux->attach_btf_id; 3402 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 3403 } 3404 3405 if (!prog->aux->dst_trampoline || 3406 (key && key != prog->aux->dst_trampoline->key)) { 3407 /* If there is no saved target, or the specified target is 3408 * different from the destination specified at load time, we 3409 * need a new trampoline and a check for compatibility 3410 */ 3411 struct bpf_attach_target_info tgt_info = {}; 3412 3413 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 3414 &tgt_info); 3415 if (err) 3416 goto out_unlock; 3417 3418 if (tgt_info.tgt_mod) { 3419 module_put(prog->aux->mod); 3420 prog->aux->mod = tgt_info.tgt_mod; 3421 } 3422 3423 tr = bpf_trampoline_get(key, &tgt_info); 3424 if (!tr) { 3425 err = -ENOMEM; 3426 goto out_unlock; 3427 } 3428 } else { 3429 /* The caller didn't specify a target, or the target was the 3430 * same as the destination supplied during program load. This 3431 * means we can reuse the trampoline and reference from program 3432 * load time, and there is no need to allocate a new one. This 3433 * can only happen once for any program, as the saved values in 3434 * prog->aux are cleared below. 3435 */ 3436 tr = prog->aux->dst_trampoline; 3437 tgt_prog = prog->aux->dst_prog; 3438 } 3439 3440 err = bpf_link_prime(&link->link.link, &link_primer); 3441 if (err) 3442 goto out_unlock; 3443 3444 err = bpf_trampoline_link_prog(&link->link, tr); 3445 if (err) { 3446 bpf_link_cleanup(&link_primer); 3447 link = NULL; 3448 goto out_unlock; 3449 } 3450 3451 link->tgt_prog = tgt_prog; 3452 link->trampoline = tr; 3453 3454 /* Always clear the trampoline and target prog from prog->aux to make 3455 * sure the original attach destination is not kept alive after a 3456 * program is (re-)attached to another target. 3457 */ 3458 if (prog->aux->dst_prog && 3459 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 3460 /* got extra prog ref from syscall, or attaching to different prog */ 3461 bpf_prog_put(prog->aux->dst_prog); 3462 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 3463 /* we allocated a new trampoline, so free the old one */ 3464 bpf_trampoline_put(prog->aux->dst_trampoline); 3465 3466 prog->aux->dst_prog = NULL; 3467 prog->aux->dst_trampoline = NULL; 3468 mutex_unlock(&prog->aux->dst_mutex); 3469 3470 return bpf_link_settle(&link_primer); 3471 out_unlock: 3472 if (tr && tr != prog->aux->dst_trampoline) 3473 bpf_trampoline_put(tr); 3474 mutex_unlock(&prog->aux->dst_mutex); 3475 kfree(link); 3476 out_put_prog: 3477 if (tgt_prog_fd && tgt_prog) 3478 bpf_prog_put(tgt_prog); 3479 return err; 3480 } 3481 3482 static void bpf_raw_tp_link_release(struct bpf_link *link) 3483 { 3484 struct bpf_raw_tp_link *raw_tp = 3485 container_of(link, struct bpf_raw_tp_link, link); 3486 3487 bpf_probe_unregister(raw_tp->btp, raw_tp); 3488 bpf_put_raw_tracepoint(raw_tp->btp); 3489 } 3490 3491 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 3492 { 3493 struct bpf_raw_tp_link *raw_tp = 3494 container_of(link, struct bpf_raw_tp_link, link); 3495 3496 kfree(raw_tp); 3497 } 3498 3499 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 3500 struct seq_file *seq) 3501 { 3502 struct bpf_raw_tp_link *raw_tp_link = 3503 container_of(link, struct bpf_raw_tp_link, link); 3504 3505 seq_printf(seq, 3506 "tp_name:\t%s\n", 3507 raw_tp_link->btp->tp->name); 3508 } 3509 3510 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, 3511 u32 len) 3512 { 3513 if (ulen >= len + 1) { 3514 if (copy_to_user(ubuf, buf, len + 1)) 3515 return -EFAULT; 3516 } else { 3517 char zero = '\0'; 3518 3519 if (copy_to_user(ubuf, buf, ulen - 1)) 3520 return -EFAULT; 3521 if (put_user(zero, ubuf + ulen - 1)) 3522 return -EFAULT; 3523 return -ENOSPC; 3524 } 3525 3526 return 0; 3527 } 3528 3529 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 3530 struct bpf_link_info *info) 3531 { 3532 struct bpf_raw_tp_link *raw_tp_link = 3533 container_of(link, struct bpf_raw_tp_link, link); 3534 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 3535 const char *tp_name = raw_tp_link->btp->tp->name; 3536 u32 ulen = info->raw_tracepoint.tp_name_len; 3537 size_t tp_len = strlen(tp_name); 3538 3539 if (!ulen ^ !ubuf) 3540 return -EINVAL; 3541 3542 info->raw_tracepoint.tp_name_len = tp_len + 1; 3543 3544 if (!ubuf) 3545 return 0; 3546 3547 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); 3548 } 3549 3550 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 3551 .release = bpf_raw_tp_link_release, 3552 .dealloc_deferred = bpf_raw_tp_link_dealloc, 3553 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 3554 .fill_link_info = bpf_raw_tp_link_fill_link_info, 3555 }; 3556 3557 #ifdef CONFIG_PERF_EVENTS 3558 struct bpf_perf_link { 3559 struct bpf_link link; 3560 struct file *perf_file; 3561 }; 3562 3563 static void bpf_perf_link_release(struct bpf_link *link) 3564 { 3565 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3566 struct perf_event *event = perf_link->perf_file->private_data; 3567 3568 perf_event_free_bpf_prog(event); 3569 fput(perf_link->perf_file); 3570 } 3571 3572 static void bpf_perf_link_dealloc(struct bpf_link *link) 3573 { 3574 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3575 3576 kfree(perf_link); 3577 } 3578 3579 static int bpf_perf_link_fill_common(const struct perf_event *event, 3580 char __user *uname, u32 ulen, 3581 u64 *probe_offset, u64 *probe_addr, 3582 u32 *fd_type, unsigned long *missed) 3583 { 3584 const char *buf; 3585 u32 prog_id; 3586 size_t len; 3587 int err; 3588 3589 if (!ulen ^ !uname) 3590 return -EINVAL; 3591 3592 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, 3593 probe_offset, probe_addr, missed); 3594 if (err) 3595 return err; 3596 if (!uname) 3597 return 0; 3598 if (buf) { 3599 len = strlen(buf); 3600 err = bpf_copy_to_user(uname, buf, ulen, len); 3601 if (err) 3602 return err; 3603 } else { 3604 char zero = '\0'; 3605 3606 if (put_user(zero, uname)) 3607 return -EFAULT; 3608 } 3609 return 0; 3610 } 3611 3612 #ifdef CONFIG_KPROBE_EVENTS 3613 static int bpf_perf_link_fill_kprobe(const struct perf_event *event, 3614 struct bpf_link_info *info) 3615 { 3616 unsigned long missed; 3617 char __user *uname; 3618 u64 addr, offset; 3619 u32 ulen, type; 3620 int err; 3621 3622 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); 3623 ulen = info->perf_event.kprobe.name_len; 3624 err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, 3625 &type, &missed); 3626 if (err) 3627 return err; 3628 if (type == BPF_FD_TYPE_KRETPROBE) 3629 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; 3630 else 3631 info->perf_event.type = BPF_PERF_EVENT_KPROBE; 3632 3633 info->perf_event.kprobe.offset = offset; 3634 info->perf_event.kprobe.missed = missed; 3635 if (!kallsyms_show_value(current_cred())) 3636 addr = 0; 3637 info->perf_event.kprobe.addr = addr; 3638 info->perf_event.kprobe.cookie = event->bpf_cookie; 3639 return 0; 3640 } 3641 #endif 3642 3643 #ifdef CONFIG_UPROBE_EVENTS 3644 static int bpf_perf_link_fill_uprobe(const struct perf_event *event, 3645 struct bpf_link_info *info) 3646 { 3647 char __user *uname; 3648 u64 addr, offset; 3649 u32 ulen, type; 3650 int err; 3651 3652 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); 3653 ulen = info->perf_event.uprobe.name_len; 3654 err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, 3655 &type, NULL); 3656 if (err) 3657 return err; 3658 3659 if (type == BPF_FD_TYPE_URETPROBE) 3660 info->perf_event.type = BPF_PERF_EVENT_URETPROBE; 3661 else 3662 info->perf_event.type = BPF_PERF_EVENT_UPROBE; 3663 info->perf_event.uprobe.offset = offset; 3664 info->perf_event.uprobe.cookie = event->bpf_cookie; 3665 return 0; 3666 } 3667 #endif 3668 3669 static int bpf_perf_link_fill_probe(const struct perf_event *event, 3670 struct bpf_link_info *info) 3671 { 3672 #ifdef CONFIG_KPROBE_EVENTS 3673 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 3674 return bpf_perf_link_fill_kprobe(event, info); 3675 #endif 3676 #ifdef CONFIG_UPROBE_EVENTS 3677 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 3678 return bpf_perf_link_fill_uprobe(event, info); 3679 #endif 3680 return -EOPNOTSUPP; 3681 } 3682 3683 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, 3684 struct bpf_link_info *info) 3685 { 3686 char __user *uname; 3687 u32 ulen; 3688 3689 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); 3690 ulen = info->perf_event.tracepoint.name_len; 3691 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; 3692 info->perf_event.tracepoint.cookie = event->bpf_cookie; 3693 return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL, NULL); 3694 } 3695 3696 static int bpf_perf_link_fill_perf_event(const struct perf_event *event, 3697 struct bpf_link_info *info) 3698 { 3699 info->perf_event.event.type = event->attr.type; 3700 info->perf_event.event.config = event->attr.config; 3701 info->perf_event.event.cookie = event->bpf_cookie; 3702 info->perf_event.type = BPF_PERF_EVENT_EVENT; 3703 return 0; 3704 } 3705 3706 static int bpf_perf_link_fill_link_info(const struct bpf_link *link, 3707 struct bpf_link_info *info) 3708 { 3709 struct bpf_perf_link *perf_link; 3710 const struct perf_event *event; 3711 3712 perf_link = container_of(link, struct bpf_perf_link, link); 3713 event = perf_get_event(perf_link->perf_file); 3714 if (IS_ERR(event)) 3715 return PTR_ERR(event); 3716 3717 switch (event->prog->type) { 3718 case BPF_PROG_TYPE_PERF_EVENT: 3719 return bpf_perf_link_fill_perf_event(event, info); 3720 case BPF_PROG_TYPE_TRACEPOINT: 3721 return bpf_perf_link_fill_tracepoint(event, info); 3722 case BPF_PROG_TYPE_KPROBE: 3723 return bpf_perf_link_fill_probe(event, info); 3724 default: 3725 return -EOPNOTSUPP; 3726 } 3727 } 3728 3729 static const struct bpf_link_ops bpf_perf_link_lops = { 3730 .release = bpf_perf_link_release, 3731 .dealloc = bpf_perf_link_dealloc, 3732 .fill_link_info = bpf_perf_link_fill_link_info, 3733 }; 3734 3735 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 3736 { 3737 struct bpf_link_primer link_primer; 3738 struct bpf_perf_link *link; 3739 struct perf_event *event; 3740 struct file *perf_file; 3741 int err; 3742 3743 if (attr->link_create.flags) 3744 return -EINVAL; 3745 3746 perf_file = perf_event_get(attr->link_create.target_fd); 3747 if (IS_ERR(perf_file)) 3748 return PTR_ERR(perf_file); 3749 3750 link = kzalloc(sizeof(*link), GFP_USER); 3751 if (!link) { 3752 err = -ENOMEM; 3753 goto out_put_file; 3754 } 3755 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 3756 link->perf_file = perf_file; 3757 3758 err = bpf_link_prime(&link->link, &link_primer); 3759 if (err) { 3760 kfree(link); 3761 goto out_put_file; 3762 } 3763 3764 event = perf_file->private_data; 3765 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3766 if (err) { 3767 bpf_link_cleanup(&link_primer); 3768 goto out_put_file; 3769 } 3770 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3771 bpf_prog_inc(prog); 3772 3773 return bpf_link_settle(&link_primer); 3774 3775 out_put_file: 3776 fput(perf_file); 3777 return err; 3778 } 3779 #else 3780 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 3781 { 3782 return -EOPNOTSUPP; 3783 } 3784 #endif /* CONFIG_PERF_EVENTS */ 3785 3786 static int bpf_raw_tp_link_attach(struct bpf_prog *prog, 3787 const char __user *user_tp_name, u64 cookie) 3788 { 3789 struct bpf_link_primer link_primer; 3790 struct bpf_raw_tp_link *link; 3791 struct bpf_raw_event_map *btp; 3792 const char *tp_name; 3793 char buf[128]; 3794 int err; 3795 3796 switch (prog->type) { 3797 case BPF_PROG_TYPE_TRACING: 3798 case BPF_PROG_TYPE_EXT: 3799 case BPF_PROG_TYPE_LSM: 3800 if (user_tp_name) 3801 /* The attach point for this category of programs 3802 * should be specified via btf_id during program load. 3803 */ 3804 return -EINVAL; 3805 if (prog->type == BPF_PROG_TYPE_TRACING && 3806 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3807 tp_name = prog->aux->attach_func_name; 3808 break; 3809 } 3810 return bpf_tracing_prog_attach(prog, 0, 0, 0); 3811 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3812 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3813 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) 3814 return -EFAULT; 3815 buf[sizeof(buf) - 1] = 0; 3816 tp_name = buf; 3817 break; 3818 default: 3819 return -EINVAL; 3820 } 3821 3822 btp = bpf_get_raw_tracepoint(tp_name); 3823 if (!btp) 3824 return -ENOENT; 3825 3826 link = kzalloc(sizeof(*link), GFP_USER); 3827 if (!link) { 3828 err = -ENOMEM; 3829 goto out_put_btp; 3830 } 3831 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3832 &bpf_raw_tp_link_lops, prog); 3833 link->btp = btp; 3834 link->cookie = cookie; 3835 3836 err = bpf_link_prime(&link->link, &link_primer); 3837 if (err) { 3838 kfree(link); 3839 goto out_put_btp; 3840 } 3841 3842 err = bpf_probe_register(link->btp, link); 3843 if (err) { 3844 bpf_link_cleanup(&link_primer); 3845 goto out_put_btp; 3846 } 3847 3848 return bpf_link_settle(&link_primer); 3849 3850 out_put_btp: 3851 bpf_put_raw_tracepoint(btp); 3852 return err; 3853 } 3854 3855 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie 3856 3857 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3858 { 3859 struct bpf_prog *prog; 3860 void __user *tp_name; 3861 __u64 cookie; 3862 int fd; 3863 3864 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3865 return -EINVAL; 3866 3867 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3868 if (IS_ERR(prog)) 3869 return PTR_ERR(prog); 3870 3871 tp_name = u64_to_user_ptr(attr->raw_tracepoint.name); 3872 cookie = attr->raw_tracepoint.cookie; 3873 fd = bpf_raw_tp_link_attach(prog, tp_name, cookie); 3874 if (fd < 0) 3875 bpf_prog_put(prog); 3876 return fd; 3877 } 3878 3879 static enum bpf_prog_type 3880 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3881 { 3882 switch (attach_type) { 3883 case BPF_CGROUP_INET_INGRESS: 3884 case BPF_CGROUP_INET_EGRESS: 3885 return BPF_PROG_TYPE_CGROUP_SKB; 3886 case BPF_CGROUP_INET_SOCK_CREATE: 3887 case BPF_CGROUP_INET_SOCK_RELEASE: 3888 case BPF_CGROUP_INET4_POST_BIND: 3889 case BPF_CGROUP_INET6_POST_BIND: 3890 return BPF_PROG_TYPE_CGROUP_SOCK; 3891 case BPF_CGROUP_INET4_BIND: 3892 case BPF_CGROUP_INET6_BIND: 3893 case BPF_CGROUP_INET4_CONNECT: 3894 case BPF_CGROUP_INET6_CONNECT: 3895 case BPF_CGROUP_UNIX_CONNECT: 3896 case BPF_CGROUP_INET4_GETPEERNAME: 3897 case BPF_CGROUP_INET6_GETPEERNAME: 3898 case BPF_CGROUP_UNIX_GETPEERNAME: 3899 case BPF_CGROUP_INET4_GETSOCKNAME: 3900 case BPF_CGROUP_INET6_GETSOCKNAME: 3901 case BPF_CGROUP_UNIX_GETSOCKNAME: 3902 case BPF_CGROUP_UDP4_SENDMSG: 3903 case BPF_CGROUP_UDP6_SENDMSG: 3904 case BPF_CGROUP_UNIX_SENDMSG: 3905 case BPF_CGROUP_UDP4_RECVMSG: 3906 case BPF_CGROUP_UDP6_RECVMSG: 3907 case BPF_CGROUP_UNIX_RECVMSG: 3908 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3909 case BPF_CGROUP_SOCK_OPS: 3910 return BPF_PROG_TYPE_SOCK_OPS; 3911 case BPF_CGROUP_DEVICE: 3912 return BPF_PROG_TYPE_CGROUP_DEVICE; 3913 case BPF_SK_MSG_VERDICT: 3914 return BPF_PROG_TYPE_SK_MSG; 3915 case BPF_SK_SKB_STREAM_PARSER: 3916 case BPF_SK_SKB_STREAM_VERDICT: 3917 case BPF_SK_SKB_VERDICT: 3918 return BPF_PROG_TYPE_SK_SKB; 3919 case BPF_LIRC_MODE2: 3920 return BPF_PROG_TYPE_LIRC_MODE2; 3921 case BPF_FLOW_DISSECTOR: 3922 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3923 case BPF_CGROUP_SYSCTL: 3924 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3925 case BPF_CGROUP_GETSOCKOPT: 3926 case BPF_CGROUP_SETSOCKOPT: 3927 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3928 case BPF_TRACE_ITER: 3929 case BPF_TRACE_RAW_TP: 3930 case BPF_TRACE_FENTRY: 3931 case BPF_TRACE_FEXIT: 3932 case BPF_MODIFY_RETURN: 3933 return BPF_PROG_TYPE_TRACING; 3934 case BPF_LSM_MAC: 3935 return BPF_PROG_TYPE_LSM; 3936 case BPF_SK_LOOKUP: 3937 return BPF_PROG_TYPE_SK_LOOKUP; 3938 case BPF_XDP: 3939 return BPF_PROG_TYPE_XDP; 3940 case BPF_LSM_CGROUP: 3941 return BPF_PROG_TYPE_LSM; 3942 case BPF_TCX_INGRESS: 3943 case BPF_TCX_EGRESS: 3944 case BPF_NETKIT_PRIMARY: 3945 case BPF_NETKIT_PEER: 3946 return BPF_PROG_TYPE_SCHED_CLS; 3947 default: 3948 return BPF_PROG_TYPE_UNSPEC; 3949 } 3950 } 3951 3952 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3953 enum bpf_attach_type attach_type) 3954 { 3955 enum bpf_prog_type ptype; 3956 3957 switch (prog->type) { 3958 case BPF_PROG_TYPE_CGROUP_SOCK: 3959 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3960 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3961 case BPF_PROG_TYPE_SK_LOOKUP: 3962 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3963 case BPF_PROG_TYPE_CGROUP_SKB: 3964 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) 3965 /* cg-skb progs can be loaded by unpriv user. 3966 * check permissions at attach time. 3967 */ 3968 return -EPERM; 3969 3970 ptype = attach_type_to_prog_type(attach_type); 3971 if (prog->type != ptype) 3972 return -EINVAL; 3973 3974 return prog->enforce_expected_attach_type && 3975 prog->expected_attach_type != attach_type ? 3976 -EINVAL : 0; 3977 case BPF_PROG_TYPE_EXT: 3978 return 0; 3979 case BPF_PROG_TYPE_NETFILTER: 3980 if (attach_type != BPF_NETFILTER) 3981 return -EINVAL; 3982 return 0; 3983 case BPF_PROG_TYPE_PERF_EVENT: 3984 case BPF_PROG_TYPE_TRACEPOINT: 3985 if (attach_type != BPF_PERF_EVENT) 3986 return -EINVAL; 3987 return 0; 3988 case BPF_PROG_TYPE_KPROBE: 3989 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && 3990 attach_type != BPF_TRACE_KPROBE_MULTI) 3991 return -EINVAL; 3992 if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION && 3993 attach_type != BPF_TRACE_KPROBE_SESSION) 3994 return -EINVAL; 3995 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && 3996 attach_type != BPF_TRACE_UPROBE_MULTI) 3997 return -EINVAL; 3998 if (attach_type != BPF_PERF_EVENT && 3999 attach_type != BPF_TRACE_KPROBE_MULTI && 4000 attach_type != BPF_TRACE_KPROBE_SESSION && 4001 attach_type != BPF_TRACE_UPROBE_MULTI) 4002 return -EINVAL; 4003 return 0; 4004 case BPF_PROG_TYPE_SCHED_CLS: 4005 if (attach_type != BPF_TCX_INGRESS && 4006 attach_type != BPF_TCX_EGRESS && 4007 attach_type != BPF_NETKIT_PRIMARY && 4008 attach_type != BPF_NETKIT_PEER) 4009 return -EINVAL; 4010 return 0; 4011 default: 4012 ptype = attach_type_to_prog_type(attach_type); 4013 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) 4014 return -EINVAL; 4015 return 0; 4016 } 4017 } 4018 4019 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision 4020 4021 #define BPF_F_ATTACH_MASK_BASE \ 4022 (BPF_F_ALLOW_OVERRIDE | \ 4023 BPF_F_ALLOW_MULTI | \ 4024 BPF_F_REPLACE) 4025 4026 #define BPF_F_ATTACH_MASK_MPROG \ 4027 (BPF_F_REPLACE | \ 4028 BPF_F_BEFORE | \ 4029 BPF_F_AFTER | \ 4030 BPF_F_ID | \ 4031 BPF_F_LINK) 4032 4033 static int bpf_prog_attach(const union bpf_attr *attr) 4034 { 4035 enum bpf_prog_type ptype; 4036 struct bpf_prog *prog; 4037 int ret; 4038 4039 if (CHECK_ATTR(BPF_PROG_ATTACH)) 4040 return -EINVAL; 4041 4042 ptype = attach_type_to_prog_type(attr->attach_type); 4043 if (ptype == BPF_PROG_TYPE_UNSPEC) 4044 return -EINVAL; 4045 if (bpf_mprog_supported(ptype)) { 4046 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4047 return -EINVAL; 4048 } else { 4049 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) 4050 return -EINVAL; 4051 if (attr->relative_fd || 4052 attr->expected_revision) 4053 return -EINVAL; 4054 } 4055 4056 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4057 if (IS_ERR(prog)) 4058 return PTR_ERR(prog); 4059 4060 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 4061 bpf_prog_put(prog); 4062 return -EINVAL; 4063 } 4064 4065 switch (ptype) { 4066 case BPF_PROG_TYPE_SK_SKB: 4067 case BPF_PROG_TYPE_SK_MSG: 4068 ret = sock_map_get_from_fd(attr, prog); 4069 break; 4070 case BPF_PROG_TYPE_LIRC_MODE2: 4071 ret = lirc_prog_attach(attr, prog); 4072 break; 4073 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4074 ret = netns_bpf_prog_attach(attr, prog); 4075 break; 4076 case BPF_PROG_TYPE_CGROUP_DEVICE: 4077 case BPF_PROG_TYPE_CGROUP_SKB: 4078 case BPF_PROG_TYPE_CGROUP_SOCK: 4079 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4080 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4081 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4082 case BPF_PROG_TYPE_SOCK_OPS: 4083 case BPF_PROG_TYPE_LSM: 4084 if (ptype == BPF_PROG_TYPE_LSM && 4085 prog->expected_attach_type != BPF_LSM_CGROUP) 4086 ret = -EINVAL; 4087 else 4088 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 4089 break; 4090 case BPF_PROG_TYPE_SCHED_CLS: 4091 if (attr->attach_type == BPF_TCX_INGRESS || 4092 attr->attach_type == BPF_TCX_EGRESS) 4093 ret = tcx_prog_attach(attr, prog); 4094 else 4095 ret = netkit_prog_attach(attr, prog); 4096 break; 4097 default: 4098 ret = -EINVAL; 4099 } 4100 4101 if (ret) 4102 bpf_prog_put(prog); 4103 return ret; 4104 } 4105 4106 #define BPF_PROG_DETACH_LAST_FIELD expected_revision 4107 4108 static int bpf_prog_detach(const union bpf_attr *attr) 4109 { 4110 struct bpf_prog *prog = NULL; 4111 enum bpf_prog_type ptype; 4112 int ret; 4113 4114 if (CHECK_ATTR(BPF_PROG_DETACH)) 4115 return -EINVAL; 4116 4117 ptype = attach_type_to_prog_type(attr->attach_type); 4118 if (bpf_mprog_supported(ptype)) { 4119 if (ptype == BPF_PROG_TYPE_UNSPEC) 4120 return -EINVAL; 4121 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4122 return -EINVAL; 4123 if (attr->attach_bpf_fd) { 4124 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4125 if (IS_ERR(prog)) 4126 return PTR_ERR(prog); 4127 } 4128 } else if (attr->attach_flags || 4129 attr->relative_fd || 4130 attr->expected_revision) { 4131 return -EINVAL; 4132 } 4133 4134 switch (ptype) { 4135 case BPF_PROG_TYPE_SK_MSG: 4136 case BPF_PROG_TYPE_SK_SKB: 4137 ret = sock_map_prog_detach(attr, ptype); 4138 break; 4139 case BPF_PROG_TYPE_LIRC_MODE2: 4140 ret = lirc_prog_detach(attr); 4141 break; 4142 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4143 ret = netns_bpf_prog_detach(attr, ptype); 4144 break; 4145 case BPF_PROG_TYPE_CGROUP_DEVICE: 4146 case BPF_PROG_TYPE_CGROUP_SKB: 4147 case BPF_PROG_TYPE_CGROUP_SOCK: 4148 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4149 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4150 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4151 case BPF_PROG_TYPE_SOCK_OPS: 4152 case BPF_PROG_TYPE_LSM: 4153 ret = cgroup_bpf_prog_detach(attr, ptype); 4154 break; 4155 case BPF_PROG_TYPE_SCHED_CLS: 4156 if (attr->attach_type == BPF_TCX_INGRESS || 4157 attr->attach_type == BPF_TCX_EGRESS) 4158 ret = tcx_prog_detach(attr, prog); 4159 else 4160 ret = netkit_prog_detach(attr, prog); 4161 break; 4162 default: 4163 ret = -EINVAL; 4164 } 4165 4166 if (prog) 4167 bpf_prog_put(prog); 4168 return ret; 4169 } 4170 4171 #define BPF_PROG_QUERY_LAST_FIELD query.revision 4172 4173 static int bpf_prog_query(const union bpf_attr *attr, 4174 union bpf_attr __user *uattr) 4175 { 4176 if (!bpf_net_capable()) 4177 return -EPERM; 4178 if (CHECK_ATTR(BPF_PROG_QUERY)) 4179 return -EINVAL; 4180 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 4181 return -EINVAL; 4182 4183 switch (attr->query.attach_type) { 4184 case BPF_CGROUP_INET_INGRESS: 4185 case BPF_CGROUP_INET_EGRESS: 4186 case BPF_CGROUP_INET_SOCK_CREATE: 4187 case BPF_CGROUP_INET_SOCK_RELEASE: 4188 case BPF_CGROUP_INET4_BIND: 4189 case BPF_CGROUP_INET6_BIND: 4190 case BPF_CGROUP_INET4_POST_BIND: 4191 case BPF_CGROUP_INET6_POST_BIND: 4192 case BPF_CGROUP_INET4_CONNECT: 4193 case BPF_CGROUP_INET6_CONNECT: 4194 case BPF_CGROUP_UNIX_CONNECT: 4195 case BPF_CGROUP_INET4_GETPEERNAME: 4196 case BPF_CGROUP_INET6_GETPEERNAME: 4197 case BPF_CGROUP_UNIX_GETPEERNAME: 4198 case BPF_CGROUP_INET4_GETSOCKNAME: 4199 case BPF_CGROUP_INET6_GETSOCKNAME: 4200 case BPF_CGROUP_UNIX_GETSOCKNAME: 4201 case BPF_CGROUP_UDP4_SENDMSG: 4202 case BPF_CGROUP_UDP6_SENDMSG: 4203 case BPF_CGROUP_UNIX_SENDMSG: 4204 case BPF_CGROUP_UDP4_RECVMSG: 4205 case BPF_CGROUP_UDP6_RECVMSG: 4206 case BPF_CGROUP_UNIX_RECVMSG: 4207 case BPF_CGROUP_SOCK_OPS: 4208 case BPF_CGROUP_DEVICE: 4209 case BPF_CGROUP_SYSCTL: 4210 case BPF_CGROUP_GETSOCKOPT: 4211 case BPF_CGROUP_SETSOCKOPT: 4212 case BPF_LSM_CGROUP: 4213 return cgroup_bpf_prog_query(attr, uattr); 4214 case BPF_LIRC_MODE2: 4215 return lirc_prog_query(attr, uattr); 4216 case BPF_FLOW_DISSECTOR: 4217 case BPF_SK_LOOKUP: 4218 return netns_bpf_prog_query(attr, uattr); 4219 case BPF_SK_SKB_STREAM_PARSER: 4220 case BPF_SK_SKB_STREAM_VERDICT: 4221 case BPF_SK_MSG_VERDICT: 4222 case BPF_SK_SKB_VERDICT: 4223 return sock_map_bpf_prog_query(attr, uattr); 4224 case BPF_TCX_INGRESS: 4225 case BPF_TCX_EGRESS: 4226 return tcx_prog_query(attr, uattr); 4227 case BPF_NETKIT_PRIMARY: 4228 case BPF_NETKIT_PEER: 4229 return netkit_prog_query(attr, uattr); 4230 default: 4231 return -EINVAL; 4232 } 4233 } 4234 4235 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size 4236 4237 static int bpf_prog_test_run(const union bpf_attr *attr, 4238 union bpf_attr __user *uattr) 4239 { 4240 struct bpf_prog *prog; 4241 int ret = -ENOTSUPP; 4242 4243 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 4244 return -EINVAL; 4245 4246 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 4247 (!attr->test.ctx_size_in && attr->test.ctx_in)) 4248 return -EINVAL; 4249 4250 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 4251 (!attr->test.ctx_size_out && attr->test.ctx_out)) 4252 return -EINVAL; 4253 4254 prog = bpf_prog_get(attr->test.prog_fd); 4255 if (IS_ERR(prog)) 4256 return PTR_ERR(prog); 4257 4258 if (prog->aux->ops->test_run) 4259 ret = prog->aux->ops->test_run(prog, attr, uattr); 4260 4261 bpf_prog_put(prog); 4262 return ret; 4263 } 4264 4265 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 4266 4267 static int bpf_obj_get_next_id(const union bpf_attr *attr, 4268 union bpf_attr __user *uattr, 4269 struct idr *idr, 4270 spinlock_t *lock) 4271 { 4272 u32 next_id = attr->start_id; 4273 int err = 0; 4274 4275 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 4276 return -EINVAL; 4277 4278 if (!capable(CAP_SYS_ADMIN)) 4279 return -EPERM; 4280 4281 next_id++; 4282 spin_lock_bh(lock); 4283 if (!idr_get_next(idr, &next_id)) 4284 err = -ENOENT; 4285 spin_unlock_bh(lock); 4286 4287 if (!err) 4288 err = put_user(next_id, &uattr->next_id); 4289 4290 return err; 4291 } 4292 4293 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 4294 { 4295 struct bpf_map *map; 4296 4297 spin_lock_bh(&map_idr_lock); 4298 again: 4299 map = idr_get_next(&map_idr, id); 4300 if (map) { 4301 map = __bpf_map_inc_not_zero(map, false); 4302 if (IS_ERR(map)) { 4303 (*id)++; 4304 goto again; 4305 } 4306 } 4307 spin_unlock_bh(&map_idr_lock); 4308 4309 return map; 4310 } 4311 4312 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 4313 { 4314 struct bpf_prog *prog; 4315 4316 spin_lock_bh(&prog_idr_lock); 4317 again: 4318 prog = idr_get_next(&prog_idr, id); 4319 if (prog) { 4320 prog = bpf_prog_inc_not_zero(prog); 4321 if (IS_ERR(prog)) { 4322 (*id)++; 4323 goto again; 4324 } 4325 } 4326 spin_unlock_bh(&prog_idr_lock); 4327 4328 return prog; 4329 } 4330 4331 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 4332 4333 struct bpf_prog *bpf_prog_by_id(u32 id) 4334 { 4335 struct bpf_prog *prog; 4336 4337 if (!id) 4338 return ERR_PTR(-ENOENT); 4339 4340 spin_lock_bh(&prog_idr_lock); 4341 prog = idr_find(&prog_idr, id); 4342 if (prog) 4343 prog = bpf_prog_inc_not_zero(prog); 4344 else 4345 prog = ERR_PTR(-ENOENT); 4346 spin_unlock_bh(&prog_idr_lock); 4347 return prog; 4348 } 4349 4350 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 4351 { 4352 struct bpf_prog *prog; 4353 u32 id = attr->prog_id; 4354 int fd; 4355 4356 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 4357 return -EINVAL; 4358 4359 if (!capable(CAP_SYS_ADMIN)) 4360 return -EPERM; 4361 4362 prog = bpf_prog_by_id(id); 4363 if (IS_ERR(prog)) 4364 return PTR_ERR(prog); 4365 4366 fd = bpf_prog_new_fd(prog); 4367 if (fd < 0) 4368 bpf_prog_put(prog); 4369 4370 return fd; 4371 } 4372 4373 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 4374 4375 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 4376 { 4377 struct bpf_map *map; 4378 u32 id = attr->map_id; 4379 int f_flags; 4380 int fd; 4381 4382 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 4383 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 4384 return -EINVAL; 4385 4386 if (!capable(CAP_SYS_ADMIN)) 4387 return -EPERM; 4388 4389 f_flags = bpf_get_file_flag(attr->open_flags); 4390 if (f_flags < 0) 4391 return f_flags; 4392 4393 spin_lock_bh(&map_idr_lock); 4394 map = idr_find(&map_idr, id); 4395 if (map) 4396 map = __bpf_map_inc_not_zero(map, true); 4397 else 4398 map = ERR_PTR(-ENOENT); 4399 spin_unlock_bh(&map_idr_lock); 4400 4401 if (IS_ERR(map)) 4402 return PTR_ERR(map); 4403 4404 fd = bpf_map_new_fd(map, f_flags); 4405 if (fd < 0) 4406 bpf_map_put_with_uref(map); 4407 4408 return fd; 4409 } 4410 4411 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 4412 unsigned long addr, u32 *off, 4413 u32 *type) 4414 { 4415 const struct bpf_map *map; 4416 int i; 4417 4418 mutex_lock(&prog->aux->used_maps_mutex); 4419 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 4420 map = prog->aux->used_maps[i]; 4421 if (map == (void *)addr) { 4422 *type = BPF_PSEUDO_MAP_FD; 4423 goto out; 4424 } 4425 if (!map->ops->map_direct_value_meta) 4426 continue; 4427 if (!map->ops->map_direct_value_meta(map, addr, off)) { 4428 *type = BPF_PSEUDO_MAP_VALUE; 4429 goto out; 4430 } 4431 } 4432 map = NULL; 4433 4434 out: 4435 mutex_unlock(&prog->aux->used_maps_mutex); 4436 return map; 4437 } 4438 4439 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 4440 const struct cred *f_cred) 4441 { 4442 const struct bpf_map *map; 4443 struct bpf_insn *insns; 4444 u32 off, type; 4445 u64 imm; 4446 u8 code; 4447 int i; 4448 4449 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 4450 GFP_USER); 4451 if (!insns) 4452 return insns; 4453 4454 for (i = 0; i < prog->len; i++) { 4455 code = insns[i].code; 4456 4457 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 4458 insns[i].code = BPF_JMP | BPF_CALL; 4459 insns[i].imm = BPF_FUNC_tail_call; 4460 /* fall-through */ 4461 } 4462 if (code == (BPF_JMP | BPF_CALL) || 4463 code == (BPF_JMP | BPF_CALL_ARGS)) { 4464 if (code == (BPF_JMP | BPF_CALL_ARGS)) 4465 insns[i].code = BPF_JMP | BPF_CALL; 4466 if (!bpf_dump_raw_ok(f_cred)) 4467 insns[i].imm = 0; 4468 continue; 4469 } 4470 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 4471 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 4472 continue; 4473 } 4474 4475 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || 4476 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { 4477 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; 4478 continue; 4479 } 4480 4481 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 4482 continue; 4483 4484 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 4485 map = bpf_map_from_imm(prog, imm, &off, &type); 4486 if (map) { 4487 insns[i].src_reg = type; 4488 insns[i].imm = map->id; 4489 insns[i + 1].imm = off; 4490 continue; 4491 } 4492 } 4493 4494 return insns; 4495 } 4496 4497 static int set_info_rec_size(struct bpf_prog_info *info) 4498 { 4499 /* 4500 * Ensure info.*_rec_size is the same as kernel expected size 4501 * 4502 * or 4503 * 4504 * Only allow zero *_rec_size if both _rec_size and _cnt are 4505 * zero. In this case, the kernel will set the expected 4506 * _rec_size back to the info. 4507 */ 4508 4509 if ((info->nr_func_info || info->func_info_rec_size) && 4510 info->func_info_rec_size != sizeof(struct bpf_func_info)) 4511 return -EINVAL; 4512 4513 if ((info->nr_line_info || info->line_info_rec_size) && 4514 info->line_info_rec_size != sizeof(struct bpf_line_info)) 4515 return -EINVAL; 4516 4517 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 4518 info->jited_line_info_rec_size != sizeof(__u64)) 4519 return -EINVAL; 4520 4521 info->func_info_rec_size = sizeof(struct bpf_func_info); 4522 info->line_info_rec_size = sizeof(struct bpf_line_info); 4523 info->jited_line_info_rec_size = sizeof(__u64); 4524 4525 return 0; 4526 } 4527 4528 static int bpf_prog_get_info_by_fd(struct file *file, 4529 struct bpf_prog *prog, 4530 const union bpf_attr *attr, 4531 union bpf_attr __user *uattr) 4532 { 4533 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4534 struct btf *attach_btf = bpf_prog_get_target_btf(prog); 4535 struct bpf_prog_info info; 4536 u32 info_len = attr->info.info_len; 4537 struct bpf_prog_kstats stats; 4538 char __user *uinsns; 4539 u32 ulen; 4540 int err; 4541 4542 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4543 if (err) 4544 return err; 4545 info_len = min_t(u32, sizeof(info), info_len); 4546 4547 memset(&info, 0, sizeof(info)); 4548 if (copy_from_user(&info, uinfo, info_len)) 4549 return -EFAULT; 4550 4551 info.type = prog->type; 4552 info.id = prog->aux->id; 4553 info.load_time = prog->aux->load_time; 4554 info.created_by_uid = from_kuid_munged(current_user_ns(), 4555 prog->aux->user->uid); 4556 info.gpl_compatible = prog->gpl_compatible; 4557 4558 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 4559 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 4560 4561 mutex_lock(&prog->aux->used_maps_mutex); 4562 ulen = info.nr_map_ids; 4563 info.nr_map_ids = prog->aux->used_map_cnt; 4564 ulen = min_t(u32, info.nr_map_ids, ulen); 4565 if (ulen) { 4566 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 4567 u32 i; 4568 4569 for (i = 0; i < ulen; i++) 4570 if (put_user(prog->aux->used_maps[i]->id, 4571 &user_map_ids[i])) { 4572 mutex_unlock(&prog->aux->used_maps_mutex); 4573 return -EFAULT; 4574 } 4575 } 4576 mutex_unlock(&prog->aux->used_maps_mutex); 4577 4578 err = set_info_rec_size(&info); 4579 if (err) 4580 return err; 4581 4582 bpf_prog_get_stats(prog, &stats); 4583 info.run_time_ns = stats.nsecs; 4584 info.run_cnt = stats.cnt; 4585 info.recursion_misses = stats.misses; 4586 4587 info.verified_insns = prog->aux->verified_insns; 4588 4589 if (!bpf_capable()) { 4590 info.jited_prog_len = 0; 4591 info.xlated_prog_len = 0; 4592 info.nr_jited_ksyms = 0; 4593 info.nr_jited_func_lens = 0; 4594 info.nr_func_info = 0; 4595 info.nr_line_info = 0; 4596 info.nr_jited_line_info = 0; 4597 goto done; 4598 } 4599 4600 ulen = info.xlated_prog_len; 4601 info.xlated_prog_len = bpf_prog_insn_size(prog); 4602 if (info.xlated_prog_len && ulen) { 4603 struct bpf_insn *insns_sanitized; 4604 bool fault; 4605 4606 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 4607 info.xlated_prog_insns = 0; 4608 goto done; 4609 } 4610 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 4611 if (!insns_sanitized) 4612 return -ENOMEM; 4613 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 4614 ulen = min_t(u32, info.xlated_prog_len, ulen); 4615 fault = copy_to_user(uinsns, insns_sanitized, ulen); 4616 kfree(insns_sanitized); 4617 if (fault) 4618 return -EFAULT; 4619 } 4620 4621 if (bpf_prog_is_offloaded(prog->aux)) { 4622 err = bpf_prog_offload_info_fill(&info, prog); 4623 if (err) 4624 return err; 4625 goto done; 4626 } 4627 4628 /* NOTE: the following code is supposed to be skipped for offload. 4629 * bpf_prog_offload_info_fill() is the place to fill similar fields 4630 * for offload. 4631 */ 4632 ulen = info.jited_prog_len; 4633 if (prog->aux->func_cnt) { 4634 u32 i; 4635 4636 info.jited_prog_len = 0; 4637 for (i = 0; i < prog->aux->func_cnt; i++) 4638 info.jited_prog_len += prog->aux->func[i]->jited_len; 4639 } else { 4640 info.jited_prog_len = prog->jited_len; 4641 } 4642 4643 if (info.jited_prog_len && ulen) { 4644 if (bpf_dump_raw_ok(file->f_cred)) { 4645 uinsns = u64_to_user_ptr(info.jited_prog_insns); 4646 ulen = min_t(u32, info.jited_prog_len, ulen); 4647 4648 /* for multi-function programs, copy the JITed 4649 * instructions for all the functions 4650 */ 4651 if (prog->aux->func_cnt) { 4652 u32 len, free, i; 4653 u8 *img; 4654 4655 free = ulen; 4656 for (i = 0; i < prog->aux->func_cnt; i++) { 4657 len = prog->aux->func[i]->jited_len; 4658 len = min_t(u32, len, free); 4659 img = (u8 *) prog->aux->func[i]->bpf_func; 4660 if (copy_to_user(uinsns, img, len)) 4661 return -EFAULT; 4662 uinsns += len; 4663 free -= len; 4664 if (!free) 4665 break; 4666 } 4667 } else { 4668 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 4669 return -EFAULT; 4670 } 4671 } else { 4672 info.jited_prog_insns = 0; 4673 } 4674 } 4675 4676 ulen = info.nr_jited_ksyms; 4677 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 4678 if (ulen) { 4679 if (bpf_dump_raw_ok(file->f_cred)) { 4680 unsigned long ksym_addr; 4681 u64 __user *user_ksyms; 4682 u32 i; 4683 4684 /* copy the address of the kernel symbol 4685 * corresponding to each function 4686 */ 4687 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 4688 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 4689 if (prog->aux->func_cnt) { 4690 for (i = 0; i < ulen; i++) { 4691 ksym_addr = (unsigned long) 4692 prog->aux->func[i]->bpf_func; 4693 if (put_user((u64) ksym_addr, 4694 &user_ksyms[i])) 4695 return -EFAULT; 4696 } 4697 } else { 4698 ksym_addr = (unsigned long) prog->bpf_func; 4699 if (put_user((u64) ksym_addr, &user_ksyms[0])) 4700 return -EFAULT; 4701 } 4702 } else { 4703 info.jited_ksyms = 0; 4704 } 4705 } 4706 4707 ulen = info.nr_jited_func_lens; 4708 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 4709 if (ulen) { 4710 if (bpf_dump_raw_ok(file->f_cred)) { 4711 u32 __user *user_lens; 4712 u32 func_len, i; 4713 4714 /* copy the JITed image lengths for each function */ 4715 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 4716 user_lens = u64_to_user_ptr(info.jited_func_lens); 4717 if (prog->aux->func_cnt) { 4718 for (i = 0; i < ulen; i++) { 4719 func_len = 4720 prog->aux->func[i]->jited_len; 4721 if (put_user(func_len, &user_lens[i])) 4722 return -EFAULT; 4723 } 4724 } else { 4725 func_len = prog->jited_len; 4726 if (put_user(func_len, &user_lens[0])) 4727 return -EFAULT; 4728 } 4729 } else { 4730 info.jited_func_lens = 0; 4731 } 4732 } 4733 4734 if (prog->aux->btf) 4735 info.btf_id = btf_obj_id(prog->aux->btf); 4736 info.attach_btf_id = prog->aux->attach_btf_id; 4737 if (attach_btf) 4738 info.attach_btf_obj_id = btf_obj_id(attach_btf); 4739 4740 ulen = info.nr_func_info; 4741 info.nr_func_info = prog->aux->func_info_cnt; 4742 if (info.nr_func_info && ulen) { 4743 char __user *user_finfo; 4744 4745 user_finfo = u64_to_user_ptr(info.func_info); 4746 ulen = min_t(u32, info.nr_func_info, ulen); 4747 if (copy_to_user(user_finfo, prog->aux->func_info, 4748 info.func_info_rec_size * ulen)) 4749 return -EFAULT; 4750 } 4751 4752 ulen = info.nr_line_info; 4753 info.nr_line_info = prog->aux->nr_linfo; 4754 if (info.nr_line_info && ulen) { 4755 __u8 __user *user_linfo; 4756 4757 user_linfo = u64_to_user_ptr(info.line_info); 4758 ulen = min_t(u32, info.nr_line_info, ulen); 4759 if (copy_to_user(user_linfo, prog->aux->linfo, 4760 info.line_info_rec_size * ulen)) 4761 return -EFAULT; 4762 } 4763 4764 ulen = info.nr_jited_line_info; 4765 if (prog->aux->jited_linfo) 4766 info.nr_jited_line_info = prog->aux->nr_linfo; 4767 else 4768 info.nr_jited_line_info = 0; 4769 if (info.nr_jited_line_info && ulen) { 4770 if (bpf_dump_raw_ok(file->f_cred)) { 4771 unsigned long line_addr; 4772 __u64 __user *user_linfo; 4773 u32 i; 4774 4775 user_linfo = u64_to_user_ptr(info.jited_line_info); 4776 ulen = min_t(u32, info.nr_jited_line_info, ulen); 4777 for (i = 0; i < ulen; i++) { 4778 line_addr = (unsigned long)prog->aux->jited_linfo[i]; 4779 if (put_user((__u64)line_addr, &user_linfo[i])) 4780 return -EFAULT; 4781 } 4782 } else { 4783 info.jited_line_info = 0; 4784 } 4785 } 4786 4787 ulen = info.nr_prog_tags; 4788 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 4789 if (ulen) { 4790 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 4791 u32 i; 4792 4793 user_prog_tags = u64_to_user_ptr(info.prog_tags); 4794 ulen = min_t(u32, info.nr_prog_tags, ulen); 4795 if (prog->aux->func_cnt) { 4796 for (i = 0; i < ulen; i++) { 4797 if (copy_to_user(user_prog_tags[i], 4798 prog->aux->func[i]->tag, 4799 BPF_TAG_SIZE)) 4800 return -EFAULT; 4801 } 4802 } else { 4803 if (copy_to_user(user_prog_tags[0], 4804 prog->tag, BPF_TAG_SIZE)) 4805 return -EFAULT; 4806 } 4807 } 4808 4809 done: 4810 if (copy_to_user(uinfo, &info, info_len) || 4811 put_user(info_len, &uattr->info.info_len)) 4812 return -EFAULT; 4813 4814 return 0; 4815 } 4816 4817 static int bpf_map_get_info_by_fd(struct file *file, 4818 struct bpf_map *map, 4819 const union bpf_attr *attr, 4820 union bpf_attr __user *uattr) 4821 { 4822 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4823 struct bpf_map_info info; 4824 u32 info_len = attr->info.info_len; 4825 int err; 4826 4827 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4828 if (err) 4829 return err; 4830 info_len = min_t(u32, sizeof(info), info_len); 4831 4832 memset(&info, 0, sizeof(info)); 4833 info.type = map->map_type; 4834 info.id = map->id; 4835 info.key_size = map->key_size; 4836 info.value_size = map->value_size; 4837 info.max_entries = map->max_entries; 4838 info.map_flags = map->map_flags; 4839 info.map_extra = map->map_extra; 4840 memcpy(info.name, map->name, sizeof(map->name)); 4841 4842 if (map->btf) { 4843 info.btf_id = btf_obj_id(map->btf); 4844 info.btf_key_type_id = map->btf_key_type_id; 4845 info.btf_value_type_id = map->btf_value_type_id; 4846 } 4847 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 4848 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) 4849 bpf_map_struct_ops_info_fill(&info, map); 4850 4851 if (bpf_map_is_offloaded(map)) { 4852 err = bpf_map_offload_info_fill(&info, map); 4853 if (err) 4854 return err; 4855 } 4856 4857 if (copy_to_user(uinfo, &info, info_len) || 4858 put_user(info_len, &uattr->info.info_len)) 4859 return -EFAULT; 4860 4861 return 0; 4862 } 4863 4864 static int bpf_btf_get_info_by_fd(struct file *file, 4865 struct btf *btf, 4866 const union bpf_attr *attr, 4867 union bpf_attr __user *uattr) 4868 { 4869 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4870 u32 info_len = attr->info.info_len; 4871 int err; 4872 4873 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 4874 if (err) 4875 return err; 4876 4877 return btf_get_info_by_fd(btf, attr, uattr); 4878 } 4879 4880 static int bpf_link_get_info_by_fd(struct file *file, 4881 struct bpf_link *link, 4882 const union bpf_attr *attr, 4883 union bpf_attr __user *uattr) 4884 { 4885 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4886 struct bpf_link_info info; 4887 u32 info_len = attr->info.info_len; 4888 int err; 4889 4890 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4891 if (err) 4892 return err; 4893 info_len = min_t(u32, sizeof(info), info_len); 4894 4895 memset(&info, 0, sizeof(info)); 4896 if (copy_from_user(&info, uinfo, info_len)) 4897 return -EFAULT; 4898 4899 info.type = link->type; 4900 info.id = link->id; 4901 if (link->prog) 4902 info.prog_id = link->prog->aux->id; 4903 4904 if (link->ops->fill_link_info) { 4905 err = link->ops->fill_link_info(link, &info); 4906 if (err) 4907 return err; 4908 } 4909 4910 if (copy_to_user(uinfo, &info, info_len) || 4911 put_user(info_len, &uattr->info.info_len)) 4912 return -EFAULT; 4913 4914 return 0; 4915 } 4916 4917 4918 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 4919 4920 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 4921 union bpf_attr __user *uattr) 4922 { 4923 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4924 return -EINVAL; 4925 4926 CLASS(fd, f)(attr->info.bpf_fd); 4927 if (fd_empty(f)) 4928 return -EBADFD; 4929 4930 if (fd_file(f)->f_op == &bpf_prog_fops) 4931 return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 4932 uattr); 4933 else if (fd_file(f)->f_op == &bpf_map_fops) 4934 return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 4935 uattr); 4936 else if (fd_file(f)->f_op == &btf_fops) 4937 return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr); 4938 else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll) 4939 return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 4940 attr, uattr); 4941 return -EINVAL; 4942 } 4943 4944 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd 4945 4946 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) 4947 { 4948 struct bpf_token *token = NULL; 4949 4950 if (CHECK_ATTR(BPF_BTF_LOAD)) 4951 return -EINVAL; 4952 4953 if (attr->btf_flags & ~BPF_F_TOKEN_FD) 4954 return -EINVAL; 4955 4956 if (attr->btf_flags & BPF_F_TOKEN_FD) { 4957 token = bpf_token_get_from_fd(attr->btf_token_fd); 4958 if (IS_ERR(token)) 4959 return PTR_ERR(token); 4960 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { 4961 bpf_token_put(token); 4962 token = NULL; 4963 } 4964 } 4965 4966 if (!bpf_token_capable(token, CAP_BPF)) { 4967 bpf_token_put(token); 4968 return -EPERM; 4969 } 4970 4971 bpf_token_put(token); 4972 4973 return btf_new_fd(attr, uattr, uattr_size); 4974 } 4975 4976 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4977 4978 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4979 { 4980 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4981 return -EINVAL; 4982 4983 if (!capable(CAP_SYS_ADMIN)) 4984 return -EPERM; 4985 4986 return btf_get_fd_by_id(attr->btf_id); 4987 } 4988 4989 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 4990 union bpf_attr __user *uattr, 4991 u32 prog_id, u32 fd_type, 4992 const char *buf, u64 probe_offset, 4993 u64 probe_addr) 4994 { 4995 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 4996 u32 len = buf ? strlen(buf) : 0, input_len; 4997 int err = 0; 4998 4999 if (put_user(len, &uattr->task_fd_query.buf_len)) 5000 return -EFAULT; 5001 input_len = attr->task_fd_query.buf_len; 5002 if (input_len && ubuf) { 5003 if (!len) { 5004 /* nothing to copy, just make ubuf NULL terminated */ 5005 char zero = '\0'; 5006 5007 if (put_user(zero, ubuf)) 5008 return -EFAULT; 5009 } else if (input_len >= len + 1) { 5010 /* ubuf can hold the string with NULL terminator */ 5011 if (copy_to_user(ubuf, buf, len + 1)) 5012 return -EFAULT; 5013 } else { 5014 /* ubuf cannot hold the string with NULL terminator, 5015 * do a partial copy with NULL terminator. 5016 */ 5017 char zero = '\0'; 5018 5019 err = -ENOSPC; 5020 if (copy_to_user(ubuf, buf, input_len - 1)) 5021 return -EFAULT; 5022 if (put_user(zero, ubuf + input_len - 1)) 5023 return -EFAULT; 5024 } 5025 } 5026 5027 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 5028 put_user(fd_type, &uattr->task_fd_query.fd_type) || 5029 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 5030 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 5031 return -EFAULT; 5032 5033 return err; 5034 } 5035 5036 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 5037 5038 static int bpf_task_fd_query(const union bpf_attr *attr, 5039 union bpf_attr __user *uattr) 5040 { 5041 pid_t pid = attr->task_fd_query.pid; 5042 u32 fd = attr->task_fd_query.fd; 5043 const struct perf_event *event; 5044 struct task_struct *task; 5045 struct file *file; 5046 int err; 5047 5048 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 5049 return -EINVAL; 5050 5051 if (!capable(CAP_SYS_ADMIN)) 5052 return -EPERM; 5053 5054 if (attr->task_fd_query.flags != 0) 5055 return -EINVAL; 5056 5057 rcu_read_lock(); 5058 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 5059 rcu_read_unlock(); 5060 if (!task) 5061 return -ENOENT; 5062 5063 err = 0; 5064 file = fget_task(task, fd); 5065 put_task_struct(task); 5066 if (!file) 5067 return -EBADF; 5068 5069 if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) { 5070 struct bpf_link *link = file->private_data; 5071 5072 if (link->ops == &bpf_raw_tp_link_lops) { 5073 struct bpf_raw_tp_link *raw_tp = 5074 container_of(link, struct bpf_raw_tp_link, link); 5075 struct bpf_raw_event_map *btp = raw_tp->btp; 5076 5077 err = bpf_task_fd_query_copy(attr, uattr, 5078 raw_tp->link.prog->aux->id, 5079 BPF_FD_TYPE_RAW_TRACEPOINT, 5080 btp->tp->name, 0, 0); 5081 goto put_file; 5082 } 5083 goto out_not_supp; 5084 } 5085 5086 event = perf_get_event(file); 5087 if (!IS_ERR(event)) { 5088 u64 probe_offset, probe_addr; 5089 u32 prog_id, fd_type; 5090 const char *buf; 5091 5092 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 5093 &buf, &probe_offset, 5094 &probe_addr, NULL); 5095 if (!err) 5096 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 5097 fd_type, buf, 5098 probe_offset, 5099 probe_addr); 5100 goto put_file; 5101 } 5102 5103 out_not_supp: 5104 err = -ENOTSUPP; 5105 put_file: 5106 fput(file); 5107 return err; 5108 } 5109 5110 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 5111 5112 #define BPF_DO_BATCH(fn, ...) \ 5113 do { \ 5114 if (!fn) { \ 5115 err = -ENOTSUPP; \ 5116 goto err_put; \ 5117 } \ 5118 err = fn(__VA_ARGS__); \ 5119 } while (0) 5120 5121 static int bpf_map_do_batch(const union bpf_attr *attr, 5122 union bpf_attr __user *uattr, 5123 int cmd) 5124 { 5125 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 5126 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 5127 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 5128 struct bpf_map *map; 5129 int err; 5130 5131 if (CHECK_ATTR(BPF_MAP_BATCH)) 5132 return -EINVAL; 5133 5134 CLASS(fd, f)(attr->batch.map_fd); 5135 5136 map = __bpf_map_get(f); 5137 if (IS_ERR(map)) 5138 return PTR_ERR(map); 5139 if (has_write) 5140 bpf_map_write_active_inc(map); 5141 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 5142 err = -EPERM; 5143 goto err_put; 5144 } 5145 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 5146 err = -EPERM; 5147 goto err_put; 5148 } 5149 5150 if (cmd == BPF_MAP_LOOKUP_BATCH) 5151 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); 5152 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 5153 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); 5154 else if (cmd == BPF_MAP_UPDATE_BATCH) 5155 BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr); 5156 else 5157 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); 5158 err_put: 5159 if (has_write) { 5160 maybe_wait_bpf_programs(map); 5161 bpf_map_write_active_dec(map); 5162 } 5163 return err; 5164 } 5165 5166 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid 5167 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 5168 { 5169 struct bpf_prog *prog; 5170 int ret; 5171 5172 if (CHECK_ATTR(BPF_LINK_CREATE)) 5173 return -EINVAL; 5174 5175 if (attr->link_create.attach_type == BPF_STRUCT_OPS) 5176 return bpf_struct_ops_link_create(attr); 5177 5178 prog = bpf_prog_get(attr->link_create.prog_fd); 5179 if (IS_ERR(prog)) 5180 return PTR_ERR(prog); 5181 5182 ret = bpf_prog_attach_check_attach_type(prog, 5183 attr->link_create.attach_type); 5184 if (ret) 5185 goto out; 5186 5187 switch (prog->type) { 5188 case BPF_PROG_TYPE_CGROUP_SKB: 5189 case BPF_PROG_TYPE_CGROUP_SOCK: 5190 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 5191 case BPF_PROG_TYPE_SOCK_OPS: 5192 case BPF_PROG_TYPE_CGROUP_DEVICE: 5193 case BPF_PROG_TYPE_CGROUP_SYSCTL: 5194 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 5195 ret = cgroup_bpf_link_attach(attr, prog); 5196 break; 5197 case BPF_PROG_TYPE_EXT: 5198 ret = bpf_tracing_prog_attach(prog, 5199 attr->link_create.target_fd, 5200 attr->link_create.target_btf_id, 5201 attr->link_create.tracing.cookie); 5202 break; 5203 case BPF_PROG_TYPE_LSM: 5204 case BPF_PROG_TYPE_TRACING: 5205 if (attr->link_create.attach_type != prog->expected_attach_type) { 5206 ret = -EINVAL; 5207 goto out; 5208 } 5209 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 5210 ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie); 5211 else if (prog->expected_attach_type == BPF_TRACE_ITER) 5212 ret = bpf_iter_link_attach(attr, uattr, prog); 5213 else if (prog->expected_attach_type == BPF_LSM_CGROUP) 5214 ret = cgroup_bpf_link_attach(attr, prog); 5215 else 5216 ret = bpf_tracing_prog_attach(prog, 5217 attr->link_create.target_fd, 5218 attr->link_create.target_btf_id, 5219 attr->link_create.tracing.cookie); 5220 break; 5221 case BPF_PROG_TYPE_FLOW_DISSECTOR: 5222 case BPF_PROG_TYPE_SK_LOOKUP: 5223 ret = netns_bpf_link_create(attr, prog); 5224 break; 5225 case BPF_PROG_TYPE_SK_MSG: 5226 case BPF_PROG_TYPE_SK_SKB: 5227 ret = sock_map_link_create(attr, prog); 5228 break; 5229 #ifdef CONFIG_NET 5230 case BPF_PROG_TYPE_XDP: 5231 ret = bpf_xdp_link_attach(attr, prog); 5232 break; 5233 case BPF_PROG_TYPE_SCHED_CLS: 5234 if (attr->link_create.attach_type == BPF_TCX_INGRESS || 5235 attr->link_create.attach_type == BPF_TCX_EGRESS) 5236 ret = tcx_link_attach(attr, prog); 5237 else 5238 ret = netkit_link_attach(attr, prog); 5239 break; 5240 case BPF_PROG_TYPE_NETFILTER: 5241 ret = bpf_nf_link_attach(attr, prog); 5242 break; 5243 #endif 5244 case BPF_PROG_TYPE_PERF_EVENT: 5245 case BPF_PROG_TYPE_TRACEPOINT: 5246 ret = bpf_perf_link_attach(attr, prog); 5247 break; 5248 case BPF_PROG_TYPE_KPROBE: 5249 if (attr->link_create.attach_type == BPF_PERF_EVENT) 5250 ret = bpf_perf_link_attach(attr, prog); 5251 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI || 5252 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION) 5253 ret = bpf_kprobe_multi_link_attach(attr, prog); 5254 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI) 5255 ret = bpf_uprobe_multi_link_attach(attr, prog); 5256 break; 5257 default: 5258 ret = -EINVAL; 5259 } 5260 5261 out: 5262 if (ret < 0) 5263 bpf_prog_put(prog); 5264 return ret; 5265 } 5266 5267 static int link_update_map(struct bpf_link *link, union bpf_attr *attr) 5268 { 5269 struct bpf_map *new_map, *old_map = NULL; 5270 int ret; 5271 5272 new_map = bpf_map_get(attr->link_update.new_map_fd); 5273 if (IS_ERR(new_map)) 5274 return PTR_ERR(new_map); 5275 5276 if (attr->link_update.flags & BPF_F_REPLACE) { 5277 old_map = bpf_map_get(attr->link_update.old_map_fd); 5278 if (IS_ERR(old_map)) { 5279 ret = PTR_ERR(old_map); 5280 goto out_put; 5281 } 5282 } else if (attr->link_update.old_map_fd) { 5283 ret = -EINVAL; 5284 goto out_put; 5285 } 5286 5287 ret = link->ops->update_map(link, new_map, old_map); 5288 5289 if (old_map) 5290 bpf_map_put(old_map); 5291 out_put: 5292 bpf_map_put(new_map); 5293 return ret; 5294 } 5295 5296 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 5297 5298 static int link_update(union bpf_attr *attr) 5299 { 5300 struct bpf_prog *old_prog = NULL, *new_prog; 5301 struct bpf_link *link; 5302 u32 flags; 5303 int ret; 5304 5305 if (CHECK_ATTR(BPF_LINK_UPDATE)) 5306 return -EINVAL; 5307 5308 flags = attr->link_update.flags; 5309 if (flags & ~BPF_F_REPLACE) 5310 return -EINVAL; 5311 5312 link = bpf_link_get_from_fd(attr->link_update.link_fd); 5313 if (IS_ERR(link)) 5314 return PTR_ERR(link); 5315 5316 if (link->ops->update_map) { 5317 ret = link_update_map(link, attr); 5318 goto out_put_link; 5319 } 5320 5321 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 5322 if (IS_ERR(new_prog)) { 5323 ret = PTR_ERR(new_prog); 5324 goto out_put_link; 5325 } 5326 5327 if (flags & BPF_F_REPLACE) { 5328 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 5329 if (IS_ERR(old_prog)) { 5330 ret = PTR_ERR(old_prog); 5331 old_prog = NULL; 5332 goto out_put_progs; 5333 } 5334 } else if (attr->link_update.old_prog_fd) { 5335 ret = -EINVAL; 5336 goto out_put_progs; 5337 } 5338 5339 if (link->ops->update_prog) 5340 ret = link->ops->update_prog(link, new_prog, old_prog); 5341 else 5342 ret = -EINVAL; 5343 5344 out_put_progs: 5345 if (old_prog) 5346 bpf_prog_put(old_prog); 5347 if (ret) 5348 bpf_prog_put(new_prog); 5349 out_put_link: 5350 bpf_link_put_direct(link); 5351 return ret; 5352 } 5353 5354 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 5355 5356 static int link_detach(union bpf_attr *attr) 5357 { 5358 struct bpf_link *link; 5359 int ret; 5360 5361 if (CHECK_ATTR(BPF_LINK_DETACH)) 5362 return -EINVAL; 5363 5364 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 5365 if (IS_ERR(link)) 5366 return PTR_ERR(link); 5367 5368 if (link->ops->detach) 5369 ret = link->ops->detach(link); 5370 else 5371 ret = -EOPNOTSUPP; 5372 5373 bpf_link_put_direct(link); 5374 return ret; 5375 } 5376 5377 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 5378 { 5379 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 5380 } 5381 EXPORT_SYMBOL(bpf_link_inc_not_zero); 5382 5383 struct bpf_link *bpf_link_by_id(u32 id) 5384 { 5385 struct bpf_link *link; 5386 5387 if (!id) 5388 return ERR_PTR(-ENOENT); 5389 5390 spin_lock_bh(&link_idr_lock); 5391 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 5392 link = idr_find(&link_idr, id); 5393 if (link) { 5394 if (link->id) 5395 link = bpf_link_inc_not_zero(link); 5396 else 5397 link = ERR_PTR(-EAGAIN); 5398 } else { 5399 link = ERR_PTR(-ENOENT); 5400 } 5401 spin_unlock_bh(&link_idr_lock); 5402 return link; 5403 } 5404 5405 struct bpf_link *bpf_link_get_curr_or_next(u32 *id) 5406 { 5407 struct bpf_link *link; 5408 5409 spin_lock_bh(&link_idr_lock); 5410 again: 5411 link = idr_get_next(&link_idr, id); 5412 if (link) { 5413 link = bpf_link_inc_not_zero(link); 5414 if (IS_ERR(link)) { 5415 (*id)++; 5416 goto again; 5417 } 5418 } 5419 spin_unlock_bh(&link_idr_lock); 5420 5421 return link; 5422 } 5423 5424 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 5425 5426 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 5427 { 5428 struct bpf_link *link; 5429 u32 id = attr->link_id; 5430 int fd; 5431 5432 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 5433 return -EINVAL; 5434 5435 if (!capable(CAP_SYS_ADMIN)) 5436 return -EPERM; 5437 5438 link = bpf_link_by_id(id); 5439 if (IS_ERR(link)) 5440 return PTR_ERR(link); 5441 5442 fd = bpf_link_new_fd(link); 5443 if (fd < 0) 5444 bpf_link_put_direct(link); 5445 5446 return fd; 5447 } 5448 5449 DEFINE_MUTEX(bpf_stats_enabled_mutex); 5450 5451 static int bpf_stats_release(struct inode *inode, struct file *file) 5452 { 5453 mutex_lock(&bpf_stats_enabled_mutex); 5454 static_key_slow_dec(&bpf_stats_enabled_key.key); 5455 mutex_unlock(&bpf_stats_enabled_mutex); 5456 return 0; 5457 } 5458 5459 static const struct file_operations bpf_stats_fops = { 5460 .release = bpf_stats_release, 5461 }; 5462 5463 static int bpf_enable_runtime_stats(void) 5464 { 5465 int fd; 5466 5467 mutex_lock(&bpf_stats_enabled_mutex); 5468 5469 /* Set a very high limit to avoid overflow */ 5470 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 5471 mutex_unlock(&bpf_stats_enabled_mutex); 5472 return -EBUSY; 5473 } 5474 5475 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 5476 if (fd >= 0) 5477 static_key_slow_inc(&bpf_stats_enabled_key.key); 5478 5479 mutex_unlock(&bpf_stats_enabled_mutex); 5480 return fd; 5481 } 5482 5483 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 5484 5485 static int bpf_enable_stats(union bpf_attr *attr) 5486 { 5487 5488 if (CHECK_ATTR(BPF_ENABLE_STATS)) 5489 return -EINVAL; 5490 5491 if (!capable(CAP_SYS_ADMIN)) 5492 return -EPERM; 5493 5494 switch (attr->enable_stats.type) { 5495 case BPF_STATS_RUN_TIME: 5496 return bpf_enable_runtime_stats(); 5497 default: 5498 break; 5499 } 5500 return -EINVAL; 5501 } 5502 5503 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 5504 5505 static int bpf_iter_create(union bpf_attr *attr) 5506 { 5507 struct bpf_link *link; 5508 int err; 5509 5510 if (CHECK_ATTR(BPF_ITER_CREATE)) 5511 return -EINVAL; 5512 5513 if (attr->iter_create.flags) 5514 return -EINVAL; 5515 5516 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 5517 if (IS_ERR(link)) 5518 return PTR_ERR(link); 5519 5520 err = bpf_iter_new_fd(link); 5521 bpf_link_put_direct(link); 5522 5523 return err; 5524 } 5525 5526 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 5527 5528 static int bpf_prog_bind_map(union bpf_attr *attr) 5529 { 5530 struct bpf_prog *prog; 5531 struct bpf_map *map; 5532 struct bpf_map **used_maps_old, **used_maps_new; 5533 int i, ret = 0; 5534 5535 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 5536 return -EINVAL; 5537 5538 if (attr->prog_bind_map.flags) 5539 return -EINVAL; 5540 5541 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 5542 if (IS_ERR(prog)) 5543 return PTR_ERR(prog); 5544 5545 map = bpf_map_get(attr->prog_bind_map.map_fd); 5546 if (IS_ERR(map)) { 5547 ret = PTR_ERR(map); 5548 goto out_prog_put; 5549 } 5550 5551 mutex_lock(&prog->aux->used_maps_mutex); 5552 5553 used_maps_old = prog->aux->used_maps; 5554 5555 for (i = 0; i < prog->aux->used_map_cnt; i++) 5556 if (used_maps_old[i] == map) { 5557 bpf_map_put(map); 5558 goto out_unlock; 5559 } 5560 5561 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 5562 sizeof(used_maps_new[0]), 5563 GFP_KERNEL); 5564 if (!used_maps_new) { 5565 ret = -ENOMEM; 5566 goto out_unlock; 5567 } 5568 5569 /* The bpf program will not access the bpf map, but for the sake of 5570 * simplicity, increase sleepable_refcnt for sleepable program as well. 5571 */ 5572 if (prog->sleepable) 5573 atomic64_inc(&map->sleepable_refcnt); 5574 memcpy(used_maps_new, used_maps_old, 5575 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 5576 used_maps_new[prog->aux->used_map_cnt] = map; 5577 5578 prog->aux->used_map_cnt++; 5579 prog->aux->used_maps = used_maps_new; 5580 5581 kfree(used_maps_old); 5582 5583 out_unlock: 5584 mutex_unlock(&prog->aux->used_maps_mutex); 5585 5586 if (ret) 5587 bpf_map_put(map); 5588 out_prog_put: 5589 bpf_prog_put(prog); 5590 return ret; 5591 } 5592 5593 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd 5594 5595 static int token_create(union bpf_attr *attr) 5596 { 5597 if (CHECK_ATTR(BPF_TOKEN_CREATE)) 5598 return -EINVAL; 5599 5600 /* no flags are supported yet */ 5601 if (attr->token_create.flags) 5602 return -EINVAL; 5603 5604 return bpf_token_create(attr); 5605 } 5606 5607 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size) 5608 { 5609 union bpf_attr attr; 5610 int err; 5611 5612 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 5613 if (err) 5614 return err; 5615 size = min_t(u32, size, sizeof(attr)); 5616 5617 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 5618 memset(&attr, 0, sizeof(attr)); 5619 if (copy_from_bpfptr(&attr, uattr, size) != 0) 5620 return -EFAULT; 5621 5622 err = security_bpf(cmd, &attr, size); 5623 if (err < 0) 5624 return err; 5625 5626 switch (cmd) { 5627 case BPF_MAP_CREATE: 5628 err = map_create(&attr); 5629 break; 5630 case BPF_MAP_LOOKUP_ELEM: 5631 err = map_lookup_elem(&attr); 5632 break; 5633 case BPF_MAP_UPDATE_ELEM: 5634 err = map_update_elem(&attr, uattr); 5635 break; 5636 case BPF_MAP_DELETE_ELEM: 5637 err = map_delete_elem(&attr, uattr); 5638 break; 5639 case BPF_MAP_GET_NEXT_KEY: 5640 err = map_get_next_key(&attr); 5641 break; 5642 case BPF_MAP_FREEZE: 5643 err = map_freeze(&attr); 5644 break; 5645 case BPF_PROG_LOAD: 5646 err = bpf_prog_load(&attr, uattr, size); 5647 break; 5648 case BPF_OBJ_PIN: 5649 err = bpf_obj_pin(&attr); 5650 break; 5651 case BPF_OBJ_GET: 5652 err = bpf_obj_get(&attr); 5653 break; 5654 case BPF_PROG_ATTACH: 5655 err = bpf_prog_attach(&attr); 5656 break; 5657 case BPF_PROG_DETACH: 5658 err = bpf_prog_detach(&attr); 5659 break; 5660 case BPF_PROG_QUERY: 5661 err = bpf_prog_query(&attr, uattr.user); 5662 break; 5663 case BPF_PROG_TEST_RUN: 5664 err = bpf_prog_test_run(&attr, uattr.user); 5665 break; 5666 case BPF_PROG_GET_NEXT_ID: 5667 err = bpf_obj_get_next_id(&attr, uattr.user, 5668 &prog_idr, &prog_idr_lock); 5669 break; 5670 case BPF_MAP_GET_NEXT_ID: 5671 err = bpf_obj_get_next_id(&attr, uattr.user, 5672 &map_idr, &map_idr_lock); 5673 break; 5674 case BPF_BTF_GET_NEXT_ID: 5675 err = bpf_obj_get_next_id(&attr, uattr.user, 5676 &btf_idr, &btf_idr_lock); 5677 break; 5678 case BPF_PROG_GET_FD_BY_ID: 5679 err = bpf_prog_get_fd_by_id(&attr); 5680 break; 5681 case BPF_MAP_GET_FD_BY_ID: 5682 err = bpf_map_get_fd_by_id(&attr); 5683 break; 5684 case BPF_OBJ_GET_INFO_BY_FD: 5685 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 5686 break; 5687 case BPF_RAW_TRACEPOINT_OPEN: 5688 err = bpf_raw_tracepoint_open(&attr); 5689 break; 5690 case BPF_BTF_LOAD: 5691 err = bpf_btf_load(&attr, uattr, size); 5692 break; 5693 case BPF_BTF_GET_FD_BY_ID: 5694 err = bpf_btf_get_fd_by_id(&attr); 5695 break; 5696 case BPF_TASK_FD_QUERY: 5697 err = bpf_task_fd_query(&attr, uattr.user); 5698 break; 5699 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 5700 err = map_lookup_and_delete_elem(&attr); 5701 break; 5702 case BPF_MAP_LOOKUP_BATCH: 5703 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 5704 break; 5705 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 5706 err = bpf_map_do_batch(&attr, uattr.user, 5707 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 5708 break; 5709 case BPF_MAP_UPDATE_BATCH: 5710 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 5711 break; 5712 case BPF_MAP_DELETE_BATCH: 5713 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 5714 break; 5715 case BPF_LINK_CREATE: 5716 err = link_create(&attr, uattr); 5717 break; 5718 case BPF_LINK_UPDATE: 5719 err = link_update(&attr); 5720 break; 5721 case BPF_LINK_GET_FD_BY_ID: 5722 err = bpf_link_get_fd_by_id(&attr); 5723 break; 5724 case BPF_LINK_GET_NEXT_ID: 5725 err = bpf_obj_get_next_id(&attr, uattr.user, 5726 &link_idr, &link_idr_lock); 5727 break; 5728 case BPF_ENABLE_STATS: 5729 err = bpf_enable_stats(&attr); 5730 break; 5731 case BPF_ITER_CREATE: 5732 err = bpf_iter_create(&attr); 5733 break; 5734 case BPF_LINK_DETACH: 5735 err = link_detach(&attr); 5736 break; 5737 case BPF_PROG_BIND_MAP: 5738 err = bpf_prog_bind_map(&attr); 5739 break; 5740 case BPF_TOKEN_CREATE: 5741 err = token_create(&attr); 5742 break; 5743 default: 5744 err = -EINVAL; 5745 break; 5746 } 5747 5748 return err; 5749 } 5750 5751 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 5752 { 5753 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 5754 } 5755 5756 static bool syscall_prog_is_valid_access(int off, int size, 5757 enum bpf_access_type type, 5758 const struct bpf_prog *prog, 5759 struct bpf_insn_access_aux *info) 5760 { 5761 if (off < 0 || off >= U16_MAX) 5762 return false; 5763 if (off % size != 0) 5764 return false; 5765 return true; 5766 } 5767 5768 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 5769 { 5770 switch (cmd) { 5771 case BPF_MAP_CREATE: 5772 case BPF_MAP_DELETE_ELEM: 5773 case BPF_MAP_UPDATE_ELEM: 5774 case BPF_MAP_FREEZE: 5775 case BPF_MAP_GET_FD_BY_ID: 5776 case BPF_PROG_LOAD: 5777 case BPF_BTF_LOAD: 5778 case BPF_LINK_CREATE: 5779 case BPF_RAW_TRACEPOINT_OPEN: 5780 break; 5781 default: 5782 return -EINVAL; 5783 } 5784 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 5785 } 5786 5787 5788 /* To shut up -Wmissing-prototypes. 5789 * This function is used by the kernel light skeleton 5790 * to load bpf programs when modules are loaded or during kernel boot. 5791 * See tools/lib/bpf/skel_internal.h 5792 */ 5793 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); 5794 5795 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5796 { 5797 struct bpf_prog * __maybe_unused prog; 5798 struct bpf_tramp_run_ctx __maybe_unused run_ctx; 5799 5800 switch (cmd) { 5801 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 5802 case BPF_PROG_TEST_RUN: 5803 if (attr->test.data_in || attr->test.data_out || 5804 attr->test.ctx_out || attr->test.duration || 5805 attr->test.repeat || attr->test.flags) 5806 return -EINVAL; 5807 5808 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 5809 if (IS_ERR(prog)) 5810 return PTR_ERR(prog); 5811 5812 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 5813 attr->test.ctx_size_in > U16_MAX) { 5814 bpf_prog_put(prog); 5815 return -EINVAL; 5816 } 5817 5818 run_ctx.bpf_cookie = 0; 5819 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { 5820 /* recursion detected */ 5821 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); 5822 bpf_prog_put(prog); 5823 return -EBUSY; 5824 } 5825 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 5826 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, 5827 &run_ctx); 5828 bpf_prog_put(prog); 5829 return 0; 5830 #endif 5831 default: 5832 return ____bpf_sys_bpf(cmd, attr, size); 5833 } 5834 } 5835 EXPORT_SYMBOL(kern_sys_bpf); 5836 5837 static const struct bpf_func_proto bpf_sys_bpf_proto = { 5838 .func = bpf_sys_bpf, 5839 .gpl_only = false, 5840 .ret_type = RET_INTEGER, 5841 .arg1_type = ARG_ANYTHING, 5842 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 5843 .arg3_type = ARG_CONST_SIZE, 5844 }; 5845 5846 const struct bpf_func_proto * __weak 5847 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5848 { 5849 return bpf_base_func_proto(func_id, prog); 5850 } 5851 5852 BPF_CALL_1(bpf_sys_close, u32, fd) 5853 { 5854 /* When bpf program calls this helper there should not be 5855 * an fdget() without matching completed fdput(). 5856 * This helper is allowed in the following callchain only: 5857 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 5858 */ 5859 return close_fd(fd); 5860 } 5861 5862 static const struct bpf_func_proto bpf_sys_close_proto = { 5863 .func = bpf_sys_close, 5864 .gpl_only = false, 5865 .ret_type = RET_INTEGER, 5866 .arg1_type = ARG_ANYTHING, 5867 }; 5868 5869 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 5870 { 5871 *res = 0; 5872 if (flags) 5873 return -EINVAL; 5874 5875 if (name_sz <= 1 || name[name_sz - 1]) 5876 return -EINVAL; 5877 5878 if (!bpf_dump_raw_ok(current_cred())) 5879 return -EPERM; 5880 5881 *res = kallsyms_lookup_name(name); 5882 return *res ? 0 : -ENOENT; 5883 } 5884 5885 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 5886 .func = bpf_kallsyms_lookup_name, 5887 .gpl_only = false, 5888 .ret_type = RET_INTEGER, 5889 .arg1_type = ARG_PTR_TO_MEM, 5890 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 5891 .arg3_type = ARG_ANYTHING, 5892 .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED, 5893 .arg4_size = sizeof(u64), 5894 }; 5895 5896 static const struct bpf_func_proto * 5897 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5898 { 5899 switch (func_id) { 5900 case BPF_FUNC_sys_bpf: 5901 return !bpf_token_capable(prog->aux->token, CAP_PERFMON) 5902 ? NULL : &bpf_sys_bpf_proto; 5903 case BPF_FUNC_btf_find_by_name_kind: 5904 return &bpf_btf_find_by_name_kind_proto; 5905 case BPF_FUNC_sys_close: 5906 return &bpf_sys_close_proto; 5907 case BPF_FUNC_kallsyms_lookup_name: 5908 return &bpf_kallsyms_lookup_name_proto; 5909 default: 5910 return tracing_prog_func_proto(func_id, prog); 5911 } 5912 } 5913 5914 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 5915 .get_func_proto = syscall_prog_func_proto, 5916 .is_valid_access = syscall_prog_is_valid_access, 5917 }; 5918 5919 const struct bpf_prog_ops bpf_syscall_prog_ops = { 5920 .test_run = bpf_prog_test_run_syscall, 5921 }; 5922 5923 #ifdef CONFIG_SYSCTL 5924 static int bpf_stats_handler(const struct ctl_table *table, int write, 5925 void *buffer, size_t *lenp, loff_t *ppos) 5926 { 5927 struct static_key *key = (struct static_key *)table->data; 5928 static int saved_val; 5929 int val, ret; 5930 struct ctl_table tmp = { 5931 .data = &val, 5932 .maxlen = sizeof(val), 5933 .mode = table->mode, 5934 .extra1 = SYSCTL_ZERO, 5935 .extra2 = SYSCTL_ONE, 5936 }; 5937 5938 if (write && !capable(CAP_SYS_ADMIN)) 5939 return -EPERM; 5940 5941 mutex_lock(&bpf_stats_enabled_mutex); 5942 val = saved_val; 5943 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 5944 if (write && !ret && val != saved_val) { 5945 if (val) 5946 static_key_slow_inc(key); 5947 else 5948 static_key_slow_dec(key); 5949 saved_val = val; 5950 } 5951 mutex_unlock(&bpf_stats_enabled_mutex); 5952 return ret; 5953 } 5954 5955 void __weak unpriv_ebpf_notify(int new_state) 5956 { 5957 } 5958 5959 static int bpf_unpriv_handler(const struct ctl_table *table, int write, 5960 void *buffer, size_t *lenp, loff_t *ppos) 5961 { 5962 int ret, unpriv_enable = *(int *)table->data; 5963 bool locked_state = unpriv_enable == 1; 5964 struct ctl_table tmp = *table; 5965 5966 if (write && !capable(CAP_SYS_ADMIN)) 5967 return -EPERM; 5968 5969 tmp.data = &unpriv_enable; 5970 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 5971 if (write && !ret) { 5972 if (locked_state && unpriv_enable != 1) 5973 return -EPERM; 5974 *(int *)table->data = unpriv_enable; 5975 } 5976 5977 if (write) 5978 unpriv_ebpf_notify(unpriv_enable); 5979 5980 return ret; 5981 } 5982 5983 static struct ctl_table bpf_syscall_table[] = { 5984 { 5985 .procname = "unprivileged_bpf_disabled", 5986 .data = &sysctl_unprivileged_bpf_disabled, 5987 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), 5988 .mode = 0644, 5989 .proc_handler = bpf_unpriv_handler, 5990 .extra1 = SYSCTL_ZERO, 5991 .extra2 = SYSCTL_TWO, 5992 }, 5993 { 5994 .procname = "bpf_stats_enabled", 5995 .data = &bpf_stats_enabled_key.key, 5996 .mode = 0644, 5997 .proc_handler = bpf_stats_handler, 5998 }, 5999 }; 6000 6001 static int __init bpf_syscall_sysctl_init(void) 6002 { 6003 register_sysctl_init("kernel", bpf_syscall_table); 6004 return 0; 6005 } 6006 late_initcall(bpf_syscall_sysctl_init); 6007 #endif /* CONFIG_SYSCTL */ 6008