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_KMEM 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_KMEM 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_KMEM 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 btf_put(rec->fields[i].kptr.btf); 554 break; 555 case BPF_LIST_HEAD: 556 case BPF_LIST_NODE: 557 case BPF_RB_ROOT: 558 case BPF_RB_NODE: 559 case BPF_SPIN_LOCK: 560 case BPF_TIMER: 561 case BPF_REFCOUNT: 562 /* Nothing to release */ 563 break; 564 default: 565 WARN_ON_ONCE(1); 566 continue; 567 } 568 } 569 kfree(rec); 570 } 571 572 void bpf_map_free_record(struct bpf_map *map) 573 { 574 btf_record_free(map->record); 575 map->record = NULL; 576 } 577 578 struct btf_record *btf_record_dup(const struct btf_record *rec) 579 { 580 const struct btf_field *fields; 581 struct btf_record *new_rec; 582 int ret, size, i; 583 584 if (IS_ERR_OR_NULL(rec)) 585 return NULL; 586 size = offsetof(struct btf_record, fields[rec->cnt]); 587 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); 588 if (!new_rec) 589 return ERR_PTR(-ENOMEM); 590 /* Do a deep copy of the btf_record */ 591 fields = rec->fields; 592 new_rec->cnt = 0; 593 for (i = 0; i < rec->cnt; i++) { 594 switch (fields[i].type) { 595 case BPF_KPTR_UNREF: 596 case BPF_KPTR_REF: 597 case BPF_KPTR_PERCPU: 598 btf_get(fields[i].kptr.btf); 599 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { 600 ret = -ENXIO; 601 goto free; 602 } 603 break; 604 case BPF_LIST_HEAD: 605 case BPF_LIST_NODE: 606 case BPF_RB_ROOT: 607 case BPF_RB_NODE: 608 case BPF_SPIN_LOCK: 609 case BPF_TIMER: 610 case BPF_REFCOUNT: 611 /* Nothing to acquire */ 612 break; 613 default: 614 ret = -EFAULT; 615 WARN_ON_ONCE(1); 616 goto free; 617 } 618 new_rec->cnt++; 619 } 620 return new_rec; 621 free: 622 btf_record_free(new_rec); 623 return ERR_PTR(ret); 624 } 625 626 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) 627 { 628 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); 629 int size; 630 631 if (!a_has_fields && !b_has_fields) 632 return true; 633 if (a_has_fields != b_has_fields) 634 return false; 635 if (rec_a->cnt != rec_b->cnt) 636 return false; 637 size = offsetof(struct btf_record, fields[rec_a->cnt]); 638 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused 639 * members are zeroed out. So memcmp is safe to do without worrying 640 * about padding/unused fields. 641 * 642 * While spin_lock, timer, and kptr have no relation to map BTF, 643 * list_head metadata is specific to map BTF, the btf and value_rec 644 * members in particular. btf is the map BTF, while value_rec points to 645 * btf_record in that map BTF. 646 * 647 * So while by default, we don't rely on the map BTF (which the records 648 * were parsed from) matching for both records, which is not backwards 649 * compatible, in case list_head is part of it, we implicitly rely on 650 * that by way of depending on memcmp succeeding for it. 651 */ 652 return !memcmp(rec_a, rec_b, size); 653 } 654 655 void bpf_obj_free_timer(const struct btf_record *rec, void *obj) 656 { 657 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) 658 return; 659 bpf_timer_cancel_and_free(obj + rec->timer_off); 660 } 661 662 void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 663 { 664 const struct btf_field *fields; 665 int i; 666 667 if (IS_ERR_OR_NULL(rec)) 668 return; 669 fields = rec->fields; 670 for (i = 0; i < rec->cnt; i++) { 671 struct btf_struct_meta *pointee_struct_meta; 672 const struct btf_field *field = &fields[i]; 673 void *field_ptr = obj + field->offset; 674 void *xchgd_field; 675 676 switch (fields[i].type) { 677 case BPF_SPIN_LOCK: 678 break; 679 case BPF_TIMER: 680 bpf_timer_cancel_and_free(field_ptr); 681 break; 682 case BPF_KPTR_UNREF: 683 WRITE_ONCE(*(u64 *)field_ptr, 0); 684 break; 685 case BPF_KPTR_REF: 686 case BPF_KPTR_PERCPU: 687 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); 688 if (!xchgd_field) 689 break; 690 691 if (!btf_is_kernel(field->kptr.btf)) { 692 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, 693 field->kptr.btf_id); 694 migrate_disable(); 695 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? 696 pointee_struct_meta->record : NULL, 697 fields[i].type == BPF_KPTR_PERCPU); 698 migrate_enable(); 699 } else { 700 field->kptr.dtor(xchgd_field); 701 } 702 break; 703 case BPF_LIST_HEAD: 704 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 705 continue; 706 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); 707 break; 708 case BPF_RB_ROOT: 709 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 710 continue; 711 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); 712 break; 713 case BPF_LIST_NODE: 714 case BPF_RB_NODE: 715 case BPF_REFCOUNT: 716 break; 717 default: 718 WARN_ON_ONCE(1); 719 continue; 720 } 721 } 722 } 723 724 /* called from workqueue */ 725 static void bpf_map_free_deferred(struct work_struct *work) 726 { 727 struct bpf_map *map = container_of(work, struct bpf_map, work); 728 struct btf_record *rec = map->record; 729 struct btf *btf = map->btf; 730 731 security_bpf_map_free(map); 732 bpf_map_release_memcg(map); 733 /* implementation dependent freeing */ 734 map->ops->map_free(map); 735 /* Delay freeing of btf_record for maps, as map_free 736 * callback usually needs access to them. It is better to do it here 737 * than require each callback to do the free itself manually. 738 * 739 * Note that the btf_record stashed in map->inner_map_meta->record was 740 * already freed using the map_free callback for map in map case which 741 * eventually calls bpf_map_free_meta, since inner_map_meta is only a 742 * template bpf_map struct used during verification. 743 */ 744 btf_record_free(rec); 745 /* Delay freeing of btf for maps, as map_free callback may need 746 * struct_meta info which will be freed with btf_put(). 747 */ 748 btf_put(btf); 749 } 750 751 static void bpf_map_put_uref(struct bpf_map *map) 752 { 753 if (atomic64_dec_and_test(&map->usercnt)) { 754 if (map->ops->map_release_uref) 755 map->ops->map_release_uref(map); 756 } 757 } 758 759 static void bpf_map_free_in_work(struct bpf_map *map) 760 { 761 INIT_WORK(&map->work, bpf_map_free_deferred); 762 /* Avoid spawning kworkers, since they all might contend 763 * for the same mutex like slab_mutex. 764 */ 765 queue_work(system_unbound_wq, &map->work); 766 } 767 768 static void bpf_map_free_rcu_gp(struct rcu_head *rcu) 769 { 770 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); 771 } 772 773 static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu) 774 { 775 if (rcu_trace_implies_rcu_gp()) 776 bpf_map_free_rcu_gp(rcu); 777 else 778 call_rcu(rcu, bpf_map_free_rcu_gp); 779 } 780 781 /* decrement map refcnt and schedule it for freeing via workqueue 782 * (underlying map implementation ops->map_free() might sleep) 783 */ 784 void bpf_map_put(struct bpf_map *map) 785 { 786 if (atomic64_dec_and_test(&map->refcnt)) { 787 /* bpf_map_free_id() must be called first */ 788 bpf_map_free_id(map); 789 790 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); 791 if (READ_ONCE(map->free_after_mult_rcu_gp)) 792 call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp); 793 else if (READ_ONCE(map->free_after_rcu_gp)) 794 call_rcu(&map->rcu, bpf_map_free_rcu_gp); 795 else 796 bpf_map_free_in_work(map); 797 } 798 } 799 EXPORT_SYMBOL_GPL(bpf_map_put); 800 801 void bpf_map_put_with_uref(struct bpf_map *map) 802 { 803 bpf_map_put_uref(map); 804 bpf_map_put(map); 805 } 806 807 static int bpf_map_release(struct inode *inode, struct file *filp) 808 { 809 struct bpf_map *map = filp->private_data; 810 811 if (map->ops->map_release) 812 map->ops->map_release(map, filp); 813 814 bpf_map_put_with_uref(map); 815 return 0; 816 } 817 818 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 819 { 820 fmode_t mode = f.file->f_mode; 821 822 /* Our file permissions may have been overridden by global 823 * map permissions facing syscall side. 824 */ 825 if (READ_ONCE(map->frozen)) 826 mode &= ~FMODE_CAN_WRITE; 827 return mode; 828 } 829 830 #ifdef CONFIG_PROC_FS 831 /* Show the memory usage of a bpf map */ 832 static u64 bpf_map_memory_usage(const struct bpf_map *map) 833 { 834 return map->ops->map_mem_usage(map); 835 } 836 837 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 838 { 839 struct bpf_map *map = filp->private_data; 840 u32 type = 0, jited = 0; 841 842 if (map_type_contains_progs(map)) { 843 spin_lock(&map->owner.lock); 844 type = map->owner.type; 845 jited = map->owner.jited; 846 spin_unlock(&map->owner.lock); 847 } 848 849 seq_printf(m, 850 "map_type:\t%u\n" 851 "key_size:\t%u\n" 852 "value_size:\t%u\n" 853 "max_entries:\t%u\n" 854 "map_flags:\t%#x\n" 855 "map_extra:\t%#llx\n" 856 "memlock:\t%llu\n" 857 "map_id:\t%u\n" 858 "frozen:\t%u\n", 859 map->map_type, 860 map->key_size, 861 map->value_size, 862 map->max_entries, 863 map->map_flags, 864 (unsigned long long)map->map_extra, 865 bpf_map_memory_usage(map), 866 map->id, 867 READ_ONCE(map->frozen)); 868 if (type) { 869 seq_printf(m, "owner_prog_type:\t%u\n", type); 870 seq_printf(m, "owner_jited:\t%u\n", jited); 871 } 872 } 873 #endif 874 875 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 876 loff_t *ppos) 877 { 878 /* We need this handler such that alloc_file() enables 879 * f_mode with FMODE_CAN_READ. 880 */ 881 return -EINVAL; 882 } 883 884 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 885 size_t siz, loff_t *ppos) 886 { 887 /* We need this handler such that alloc_file() enables 888 * f_mode with FMODE_CAN_WRITE. 889 */ 890 return -EINVAL; 891 } 892 893 /* called for any extra memory-mapped regions (except initial) */ 894 static void bpf_map_mmap_open(struct vm_area_struct *vma) 895 { 896 struct bpf_map *map = vma->vm_file->private_data; 897 898 if (vma->vm_flags & VM_MAYWRITE) 899 bpf_map_write_active_inc(map); 900 } 901 902 /* called for all unmapped memory region (including initial) */ 903 static void bpf_map_mmap_close(struct vm_area_struct *vma) 904 { 905 struct bpf_map *map = vma->vm_file->private_data; 906 907 if (vma->vm_flags & VM_MAYWRITE) 908 bpf_map_write_active_dec(map); 909 } 910 911 static const struct vm_operations_struct bpf_map_default_vmops = { 912 .open = bpf_map_mmap_open, 913 .close = bpf_map_mmap_close, 914 }; 915 916 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 917 { 918 struct bpf_map *map = filp->private_data; 919 int err; 920 921 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) 922 return -ENOTSUPP; 923 924 if (!(vma->vm_flags & VM_SHARED)) 925 return -EINVAL; 926 927 mutex_lock(&map->freeze_mutex); 928 929 if (vma->vm_flags & VM_WRITE) { 930 if (map->frozen) { 931 err = -EPERM; 932 goto out; 933 } 934 /* map is meant to be read-only, so do not allow mapping as 935 * writable, because it's possible to leak a writable page 936 * reference and allows user-space to still modify it after 937 * freezing, while verifier will assume contents do not change 938 */ 939 if (map->map_flags & BPF_F_RDONLY_PROG) { 940 err = -EACCES; 941 goto out; 942 } 943 } 944 945 /* set default open/close callbacks */ 946 vma->vm_ops = &bpf_map_default_vmops; 947 vma->vm_private_data = map; 948 vm_flags_clear(vma, VM_MAYEXEC); 949 if (!(vma->vm_flags & VM_WRITE)) 950 /* disallow re-mapping with PROT_WRITE */ 951 vm_flags_clear(vma, VM_MAYWRITE); 952 953 err = map->ops->map_mmap(map, vma); 954 if (err) 955 goto out; 956 957 if (vma->vm_flags & VM_MAYWRITE) 958 bpf_map_write_active_inc(map); 959 out: 960 mutex_unlock(&map->freeze_mutex); 961 return err; 962 } 963 964 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 965 { 966 struct bpf_map *map = filp->private_data; 967 968 if (map->ops->map_poll) 969 return map->ops->map_poll(map, filp, pts); 970 971 return EPOLLERR; 972 } 973 974 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, 975 unsigned long len, unsigned long pgoff, 976 unsigned long flags) 977 { 978 struct bpf_map *map = filp->private_data; 979 980 if (map->ops->map_get_unmapped_area) 981 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); 982 #ifdef CONFIG_MMU 983 return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags); 984 #else 985 return addr; 986 #endif 987 } 988 989 const struct file_operations bpf_map_fops = { 990 #ifdef CONFIG_PROC_FS 991 .show_fdinfo = bpf_map_show_fdinfo, 992 #endif 993 .release = bpf_map_release, 994 .read = bpf_dummy_read, 995 .write = bpf_dummy_write, 996 .mmap = bpf_map_mmap, 997 .poll = bpf_map_poll, 998 .get_unmapped_area = bpf_get_unmapped_area, 999 }; 1000 1001 int bpf_map_new_fd(struct bpf_map *map, int flags) 1002 { 1003 int ret; 1004 1005 ret = security_bpf_map(map, OPEN_FMODE(flags)); 1006 if (ret < 0) 1007 return ret; 1008 1009 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 1010 flags | O_CLOEXEC); 1011 } 1012 1013 int bpf_get_file_flag(int flags) 1014 { 1015 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 1016 return -EINVAL; 1017 if (flags & BPF_F_RDONLY) 1018 return O_RDONLY; 1019 if (flags & BPF_F_WRONLY) 1020 return O_WRONLY; 1021 return O_RDWR; 1022 } 1023 1024 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 1025 #define CHECK_ATTR(CMD) \ 1026 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 1027 sizeof(attr->CMD##_LAST_FIELD), 0, \ 1028 sizeof(*attr) - \ 1029 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 1030 sizeof(attr->CMD##_LAST_FIELD)) != NULL 1031 1032 /* dst and src must have at least "size" number of bytes. 1033 * Return strlen on success and < 0 on error. 1034 */ 1035 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 1036 { 1037 const char *end = src + size; 1038 const char *orig_src = src; 1039 1040 memset(dst, 0, size); 1041 /* Copy all isalnum(), '_' and '.' chars. */ 1042 while (src < end && *src) { 1043 if (!isalnum(*src) && 1044 *src != '_' && *src != '.') 1045 return -EINVAL; 1046 *dst++ = *src++; 1047 } 1048 1049 /* No '\0' found in "size" number of bytes */ 1050 if (src == end) 1051 return -EINVAL; 1052 1053 return src - orig_src; 1054 } 1055 1056 int map_check_no_btf(const struct bpf_map *map, 1057 const struct btf *btf, 1058 const struct btf_type *key_type, 1059 const struct btf_type *value_type) 1060 { 1061 return -ENOTSUPP; 1062 } 1063 1064 static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 1065 const struct btf *btf, u32 btf_key_id, u32 btf_value_id) 1066 { 1067 const struct btf_type *key_type, *value_type; 1068 u32 key_size, value_size; 1069 int ret = 0; 1070 1071 /* Some maps allow key to be unspecified. */ 1072 if (btf_key_id) { 1073 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 1074 if (!key_type || key_size != map->key_size) 1075 return -EINVAL; 1076 } else { 1077 key_type = btf_type_by_id(btf, 0); 1078 if (!map->ops->map_check_btf) 1079 return -EINVAL; 1080 } 1081 1082 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 1083 if (!value_type || value_size != map->value_size) 1084 return -EINVAL; 1085 1086 map->record = btf_parse_fields(btf, value_type, 1087 BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | 1088 BPF_RB_ROOT | BPF_REFCOUNT, 1089 map->value_size); 1090 if (!IS_ERR_OR_NULL(map->record)) { 1091 int i; 1092 1093 if (!bpf_token_capable(token, CAP_BPF)) { 1094 ret = -EPERM; 1095 goto free_map_tab; 1096 } 1097 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { 1098 ret = -EACCES; 1099 goto free_map_tab; 1100 } 1101 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { 1102 switch (map->record->field_mask & (1 << i)) { 1103 case 0: 1104 continue; 1105 case BPF_SPIN_LOCK: 1106 if (map->map_type != BPF_MAP_TYPE_HASH && 1107 map->map_type != BPF_MAP_TYPE_ARRAY && 1108 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 1109 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1110 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1111 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1112 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1113 ret = -EOPNOTSUPP; 1114 goto free_map_tab; 1115 } 1116 break; 1117 case BPF_TIMER: 1118 if (map->map_type != BPF_MAP_TYPE_HASH && 1119 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1120 map->map_type != BPF_MAP_TYPE_ARRAY) { 1121 ret = -EOPNOTSUPP; 1122 goto free_map_tab; 1123 } 1124 break; 1125 case BPF_KPTR_UNREF: 1126 case BPF_KPTR_REF: 1127 case BPF_KPTR_PERCPU: 1128 case BPF_REFCOUNT: 1129 if (map->map_type != BPF_MAP_TYPE_HASH && 1130 map->map_type != BPF_MAP_TYPE_PERCPU_HASH && 1131 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1132 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && 1133 map->map_type != BPF_MAP_TYPE_ARRAY && 1134 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && 1135 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1136 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1137 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1138 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1139 ret = -EOPNOTSUPP; 1140 goto free_map_tab; 1141 } 1142 break; 1143 case BPF_LIST_HEAD: 1144 case BPF_RB_ROOT: 1145 if (map->map_type != BPF_MAP_TYPE_HASH && 1146 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1147 map->map_type != BPF_MAP_TYPE_ARRAY) { 1148 ret = -EOPNOTSUPP; 1149 goto free_map_tab; 1150 } 1151 break; 1152 default: 1153 /* Fail if map_type checks are missing for a field type */ 1154 ret = -EOPNOTSUPP; 1155 goto free_map_tab; 1156 } 1157 } 1158 } 1159 1160 ret = btf_check_and_fixup_fields(btf, map->record); 1161 if (ret < 0) 1162 goto free_map_tab; 1163 1164 if (map->ops->map_check_btf) { 1165 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 1166 if (ret < 0) 1167 goto free_map_tab; 1168 } 1169 1170 return ret; 1171 free_map_tab: 1172 bpf_map_free_record(map); 1173 return ret; 1174 } 1175 1176 static bool bpf_net_capable(void) 1177 { 1178 return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN); 1179 } 1180 1181 #define BPF_MAP_CREATE_LAST_FIELD map_token_fd 1182 /* called via syscall */ 1183 static int map_create(union bpf_attr *attr) 1184 { 1185 const struct bpf_map_ops *ops; 1186 struct bpf_token *token = NULL; 1187 int numa_node = bpf_map_attr_numa_node(attr); 1188 u32 map_type = attr->map_type; 1189 struct bpf_map *map; 1190 bool token_flag; 1191 int f_flags; 1192 int err; 1193 1194 err = CHECK_ATTR(BPF_MAP_CREATE); 1195 if (err) 1196 return -EINVAL; 1197 1198 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it 1199 * to avoid per-map type checks tripping on unknown flag 1200 */ 1201 token_flag = attr->map_flags & BPF_F_TOKEN_FD; 1202 attr->map_flags &= ~BPF_F_TOKEN_FD; 1203 1204 if (attr->btf_vmlinux_value_type_id) { 1205 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 1206 attr->btf_key_type_id || attr->btf_value_type_id) 1207 return -EINVAL; 1208 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 1209 return -EINVAL; 1210 } 1211 1212 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 1213 attr->map_type != BPF_MAP_TYPE_ARENA && 1214 attr->map_extra != 0) 1215 return -EINVAL; 1216 1217 f_flags = bpf_get_file_flag(attr->map_flags); 1218 if (f_flags < 0) 1219 return f_flags; 1220 1221 if (numa_node != NUMA_NO_NODE && 1222 ((unsigned int)numa_node >= nr_node_ids || 1223 !node_online(numa_node))) 1224 return -EINVAL; 1225 1226 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 1227 map_type = attr->map_type; 1228 if (map_type >= ARRAY_SIZE(bpf_map_types)) 1229 return -EINVAL; 1230 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); 1231 ops = bpf_map_types[map_type]; 1232 if (!ops) 1233 return -EINVAL; 1234 1235 if (ops->map_alloc_check) { 1236 err = ops->map_alloc_check(attr); 1237 if (err) 1238 return err; 1239 } 1240 if (attr->map_ifindex) 1241 ops = &bpf_map_offload_ops; 1242 if (!ops->map_mem_usage) 1243 return -EINVAL; 1244 1245 if (token_flag) { 1246 token = bpf_token_get_from_fd(attr->map_token_fd); 1247 if (IS_ERR(token)) 1248 return PTR_ERR(token); 1249 1250 /* if current token doesn't grant map creation permissions, 1251 * then we can't use this token, so ignore it and rely on 1252 * system-wide capabilities checks 1253 */ 1254 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || 1255 !bpf_token_allow_map_type(token, attr->map_type)) { 1256 bpf_token_put(token); 1257 token = NULL; 1258 } 1259 } 1260 1261 err = -EPERM; 1262 1263 /* Intent here is for unprivileged_bpf_disabled to block BPF map 1264 * creation for unprivileged users; other actions depend 1265 * on fd availability and access to bpffs, so are dependent on 1266 * object creation success. Even with unprivileged BPF disabled, 1267 * capability checks are still carried out. 1268 */ 1269 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) 1270 goto put_token; 1271 1272 /* check privileged map type permissions */ 1273 switch (map_type) { 1274 case BPF_MAP_TYPE_ARRAY: 1275 case BPF_MAP_TYPE_PERCPU_ARRAY: 1276 case BPF_MAP_TYPE_PROG_ARRAY: 1277 case BPF_MAP_TYPE_PERF_EVENT_ARRAY: 1278 case BPF_MAP_TYPE_CGROUP_ARRAY: 1279 case BPF_MAP_TYPE_ARRAY_OF_MAPS: 1280 case BPF_MAP_TYPE_HASH: 1281 case BPF_MAP_TYPE_PERCPU_HASH: 1282 case BPF_MAP_TYPE_HASH_OF_MAPS: 1283 case BPF_MAP_TYPE_RINGBUF: 1284 case BPF_MAP_TYPE_USER_RINGBUF: 1285 case BPF_MAP_TYPE_CGROUP_STORAGE: 1286 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: 1287 /* unprivileged */ 1288 break; 1289 case BPF_MAP_TYPE_SK_STORAGE: 1290 case BPF_MAP_TYPE_INODE_STORAGE: 1291 case BPF_MAP_TYPE_TASK_STORAGE: 1292 case BPF_MAP_TYPE_CGRP_STORAGE: 1293 case BPF_MAP_TYPE_BLOOM_FILTER: 1294 case BPF_MAP_TYPE_LPM_TRIE: 1295 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: 1296 case BPF_MAP_TYPE_STACK_TRACE: 1297 case BPF_MAP_TYPE_QUEUE: 1298 case BPF_MAP_TYPE_STACK: 1299 case BPF_MAP_TYPE_LRU_HASH: 1300 case BPF_MAP_TYPE_LRU_PERCPU_HASH: 1301 case BPF_MAP_TYPE_STRUCT_OPS: 1302 case BPF_MAP_TYPE_CPUMAP: 1303 case BPF_MAP_TYPE_ARENA: 1304 if (!bpf_token_capable(token, CAP_BPF)) 1305 goto put_token; 1306 break; 1307 case BPF_MAP_TYPE_SOCKMAP: 1308 case BPF_MAP_TYPE_SOCKHASH: 1309 case BPF_MAP_TYPE_DEVMAP: 1310 case BPF_MAP_TYPE_DEVMAP_HASH: 1311 case BPF_MAP_TYPE_XSKMAP: 1312 if (!bpf_token_capable(token, CAP_NET_ADMIN)) 1313 goto put_token; 1314 break; 1315 default: 1316 WARN(1, "unsupported map type %d", map_type); 1317 goto put_token; 1318 } 1319 1320 map = ops->map_alloc(attr); 1321 if (IS_ERR(map)) { 1322 err = PTR_ERR(map); 1323 goto put_token; 1324 } 1325 map->ops = ops; 1326 map->map_type = map_type; 1327 1328 err = bpf_obj_name_cpy(map->name, attr->map_name, 1329 sizeof(attr->map_name)); 1330 if (err < 0) 1331 goto free_map; 1332 1333 atomic64_set(&map->refcnt, 1); 1334 atomic64_set(&map->usercnt, 1); 1335 mutex_init(&map->freeze_mutex); 1336 spin_lock_init(&map->owner.lock); 1337 1338 if (attr->btf_key_type_id || attr->btf_value_type_id || 1339 /* Even the map's value is a kernel's struct, 1340 * the bpf_prog.o must have BTF to begin with 1341 * to figure out the corresponding kernel's 1342 * counter part. Thus, attr->btf_fd has 1343 * to be valid also. 1344 */ 1345 attr->btf_vmlinux_value_type_id) { 1346 struct btf *btf; 1347 1348 btf = btf_get_by_fd(attr->btf_fd); 1349 if (IS_ERR(btf)) { 1350 err = PTR_ERR(btf); 1351 goto free_map; 1352 } 1353 if (btf_is_kernel(btf)) { 1354 btf_put(btf); 1355 err = -EACCES; 1356 goto free_map; 1357 } 1358 map->btf = btf; 1359 1360 if (attr->btf_value_type_id) { 1361 err = map_check_btf(map, token, btf, attr->btf_key_type_id, 1362 attr->btf_value_type_id); 1363 if (err) 1364 goto free_map; 1365 } 1366 1367 map->btf_key_type_id = attr->btf_key_type_id; 1368 map->btf_value_type_id = attr->btf_value_type_id; 1369 map->btf_vmlinux_value_type_id = 1370 attr->btf_vmlinux_value_type_id; 1371 } 1372 1373 err = security_bpf_map_create(map, attr, token); 1374 if (err) 1375 goto free_map_sec; 1376 1377 err = bpf_map_alloc_id(map); 1378 if (err) 1379 goto free_map_sec; 1380 1381 bpf_map_save_memcg(map); 1382 bpf_token_put(token); 1383 1384 err = bpf_map_new_fd(map, f_flags); 1385 if (err < 0) { 1386 /* failed to allocate fd. 1387 * bpf_map_put_with_uref() is needed because the above 1388 * bpf_map_alloc_id() has published the map 1389 * to the userspace and the userspace may 1390 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 1391 */ 1392 bpf_map_put_with_uref(map); 1393 return err; 1394 } 1395 1396 return err; 1397 1398 free_map_sec: 1399 security_bpf_map_free(map); 1400 free_map: 1401 btf_put(map->btf); 1402 map->ops->map_free(map); 1403 put_token: 1404 bpf_token_put(token); 1405 return err; 1406 } 1407 1408 /* if error is returned, fd is released. 1409 * On success caller should complete fd access with matching fdput() 1410 */ 1411 struct bpf_map *__bpf_map_get(struct fd f) 1412 { 1413 if (!f.file) 1414 return ERR_PTR(-EBADF); 1415 if (f.file->f_op != &bpf_map_fops) { 1416 fdput(f); 1417 return ERR_PTR(-EINVAL); 1418 } 1419 1420 return f.file->private_data; 1421 } 1422 1423 void bpf_map_inc(struct bpf_map *map) 1424 { 1425 atomic64_inc(&map->refcnt); 1426 } 1427 EXPORT_SYMBOL_GPL(bpf_map_inc); 1428 1429 void bpf_map_inc_with_uref(struct bpf_map *map) 1430 { 1431 atomic64_inc(&map->refcnt); 1432 atomic64_inc(&map->usercnt); 1433 } 1434 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 1435 1436 struct bpf_map *bpf_map_get(u32 ufd) 1437 { 1438 struct fd f = fdget(ufd); 1439 struct bpf_map *map; 1440 1441 map = __bpf_map_get(f); 1442 if (IS_ERR(map)) 1443 return map; 1444 1445 bpf_map_inc(map); 1446 fdput(f); 1447 1448 return map; 1449 } 1450 EXPORT_SYMBOL(bpf_map_get); 1451 1452 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 1453 { 1454 struct fd f = fdget(ufd); 1455 struct bpf_map *map; 1456 1457 map = __bpf_map_get(f); 1458 if (IS_ERR(map)) 1459 return map; 1460 1461 bpf_map_inc_with_uref(map); 1462 fdput(f); 1463 1464 return map; 1465 } 1466 1467 /* map_idr_lock should have been held or the map should have been 1468 * protected by rcu read lock. 1469 */ 1470 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1471 { 1472 int refold; 1473 1474 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1475 if (!refold) 1476 return ERR_PTR(-ENOENT); 1477 if (uref) 1478 atomic64_inc(&map->usercnt); 1479 1480 return map; 1481 } 1482 1483 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1484 { 1485 spin_lock_bh(&map_idr_lock); 1486 map = __bpf_map_inc_not_zero(map, false); 1487 spin_unlock_bh(&map_idr_lock); 1488 1489 return map; 1490 } 1491 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1492 1493 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1494 { 1495 return -ENOTSUPP; 1496 } 1497 1498 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1499 { 1500 if (key_size) 1501 return vmemdup_user(ukey, key_size); 1502 1503 if (ukey) 1504 return ERR_PTR(-EINVAL); 1505 1506 return NULL; 1507 } 1508 1509 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1510 { 1511 if (key_size) 1512 return kvmemdup_bpfptr(ukey, key_size); 1513 1514 if (!bpfptr_is_null(ukey)) 1515 return ERR_PTR(-EINVAL); 1516 1517 return NULL; 1518 } 1519 1520 /* last field in 'union bpf_attr' used by this command */ 1521 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1522 1523 static int map_lookup_elem(union bpf_attr *attr) 1524 { 1525 void __user *ukey = u64_to_user_ptr(attr->key); 1526 void __user *uvalue = u64_to_user_ptr(attr->value); 1527 int ufd = attr->map_fd; 1528 struct bpf_map *map; 1529 void *key, *value; 1530 u32 value_size; 1531 struct fd f; 1532 int err; 1533 1534 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1535 return -EINVAL; 1536 1537 if (attr->flags & ~BPF_F_LOCK) 1538 return -EINVAL; 1539 1540 f = fdget(ufd); 1541 map = __bpf_map_get(f); 1542 if (IS_ERR(map)) 1543 return PTR_ERR(map); 1544 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1545 err = -EPERM; 1546 goto err_put; 1547 } 1548 1549 if ((attr->flags & BPF_F_LOCK) && 1550 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1551 err = -EINVAL; 1552 goto err_put; 1553 } 1554 1555 key = __bpf_copy_key(ukey, map->key_size); 1556 if (IS_ERR(key)) { 1557 err = PTR_ERR(key); 1558 goto err_put; 1559 } 1560 1561 value_size = bpf_map_value_size(map); 1562 1563 err = -ENOMEM; 1564 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1565 if (!value) 1566 goto free_key; 1567 1568 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1569 if (copy_from_user(value, uvalue, value_size)) 1570 err = -EFAULT; 1571 else 1572 err = bpf_map_copy_value(map, key, value, attr->flags); 1573 goto free_value; 1574 } 1575 1576 err = bpf_map_copy_value(map, key, value, attr->flags); 1577 if (err) 1578 goto free_value; 1579 1580 err = -EFAULT; 1581 if (copy_to_user(uvalue, value, value_size) != 0) 1582 goto free_value; 1583 1584 err = 0; 1585 1586 free_value: 1587 kvfree(value); 1588 free_key: 1589 kvfree(key); 1590 err_put: 1591 fdput(f); 1592 return err; 1593 } 1594 1595 1596 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1597 1598 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1599 { 1600 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1601 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1602 int ufd = attr->map_fd; 1603 struct bpf_map *map; 1604 void *key, *value; 1605 u32 value_size; 1606 struct fd f; 1607 int err; 1608 1609 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1610 return -EINVAL; 1611 1612 f = fdget(ufd); 1613 map = __bpf_map_get(f); 1614 if (IS_ERR(map)) 1615 return PTR_ERR(map); 1616 bpf_map_write_active_inc(map); 1617 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1618 err = -EPERM; 1619 goto err_put; 1620 } 1621 1622 if ((attr->flags & BPF_F_LOCK) && 1623 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1624 err = -EINVAL; 1625 goto err_put; 1626 } 1627 1628 key = ___bpf_copy_key(ukey, map->key_size); 1629 if (IS_ERR(key)) { 1630 err = PTR_ERR(key); 1631 goto err_put; 1632 } 1633 1634 value_size = bpf_map_value_size(map); 1635 value = kvmemdup_bpfptr(uvalue, value_size); 1636 if (IS_ERR(value)) { 1637 err = PTR_ERR(value); 1638 goto free_key; 1639 } 1640 1641 err = bpf_map_update_value(map, f.file, key, value, attr->flags); 1642 if (!err) 1643 maybe_wait_bpf_programs(map); 1644 1645 kvfree(value); 1646 free_key: 1647 kvfree(key); 1648 err_put: 1649 bpf_map_write_active_dec(map); 1650 fdput(f); 1651 return err; 1652 } 1653 1654 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1655 1656 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) 1657 { 1658 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1659 int ufd = attr->map_fd; 1660 struct bpf_map *map; 1661 struct fd f; 1662 void *key; 1663 int err; 1664 1665 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1666 return -EINVAL; 1667 1668 f = fdget(ufd); 1669 map = __bpf_map_get(f); 1670 if (IS_ERR(map)) 1671 return PTR_ERR(map); 1672 bpf_map_write_active_inc(map); 1673 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1674 err = -EPERM; 1675 goto err_put; 1676 } 1677 1678 key = ___bpf_copy_key(ukey, map->key_size); 1679 if (IS_ERR(key)) { 1680 err = PTR_ERR(key); 1681 goto err_put; 1682 } 1683 1684 if (bpf_map_is_offloaded(map)) { 1685 err = bpf_map_offload_delete_elem(map, key); 1686 goto out; 1687 } else if (IS_FD_PROG_ARRAY(map) || 1688 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1689 /* These maps require sleepable context */ 1690 err = map->ops->map_delete_elem(map, key); 1691 goto out; 1692 } 1693 1694 bpf_disable_instrumentation(); 1695 rcu_read_lock(); 1696 err = map->ops->map_delete_elem(map, key); 1697 rcu_read_unlock(); 1698 bpf_enable_instrumentation(); 1699 if (!err) 1700 maybe_wait_bpf_programs(map); 1701 out: 1702 kvfree(key); 1703 err_put: 1704 bpf_map_write_active_dec(map); 1705 fdput(f); 1706 return err; 1707 } 1708 1709 /* last field in 'union bpf_attr' used by this command */ 1710 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1711 1712 static int map_get_next_key(union bpf_attr *attr) 1713 { 1714 void __user *ukey = u64_to_user_ptr(attr->key); 1715 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1716 int ufd = attr->map_fd; 1717 struct bpf_map *map; 1718 void *key, *next_key; 1719 struct fd f; 1720 int err; 1721 1722 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1723 return -EINVAL; 1724 1725 f = fdget(ufd); 1726 map = __bpf_map_get(f); 1727 if (IS_ERR(map)) 1728 return PTR_ERR(map); 1729 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 1730 err = -EPERM; 1731 goto err_put; 1732 } 1733 1734 if (ukey) { 1735 key = __bpf_copy_key(ukey, map->key_size); 1736 if (IS_ERR(key)) { 1737 err = PTR_ERR(key); 1738 goto err_put; 1739 } 1740 } else { 1741 key = NULL; 1742 } 1743 1744 err = -ENOMEM; 1745 next_key = kvmalloc(map->key_size, GFP_USER); 1746 if (!next_key) 1747 goto free_key; 1748 1749 if (bpf_map_is_offloaded(map)) { 1750 err = bpf_map_offload_get_next_key(map, key, next_key); 1751 goto out; 1752 } 1753 1754 rcu_read_lock(); 1755 err = map->ops->map_get_next_key(map, key, next_key); 1756 rcu_read_unlock(); 1757 out: 1758 if (err) 1759 goto free_next_key; 1760 1761 err = -EFAULT; 1762 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1763 goto free_next_key; 1764 1765 err = 0; 1766 1767 free_next_key: 1768 kvfree(next_key); 1769 free_key: 1770 kvfree(key); 1771 err_put: 1772 fdput(f); 1773 return err; 1774 } 1775 1776 int generic_map_delete_batch(struct bpf_map *map, 1777 const union bpf_attr *attr, 1778 union bpf_attr __user *uattr) 1779 { 1780 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1781 u32 cp, max_count; 1782 int err = 0; 1783 void *key; 1784 1785 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1786 return -EINVAL; 1787 1788 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1789 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1790 return -EINVAL; 1791 } 1792 1793 max_count = attr->batch.count; 1794 if (!max_count) 1795 return 0; 1796 1797 if (put_user(0, &uattr->batch.count)) 1798 return -EFAULT; 1799 1800 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1801 if (!key) 1802 return -ENOMEM; 1803 1804 for (cp = 0; cp < max_count; cp++) { 1805 err = -EFAULT; 1806 if (copy_from_user(key, keys + cp * map->key_size, 1807 map->key_size)) 1808 break; 1809 1810 if (bpf_map_is_offloaded(map)) { 1811 err = bpf_map_offload_delete_elem(map, key); 1812 break; 1813 } 1814 1815 bpf_disable_instrumentation(); 1816 rcu_read_lock(); 1817 err = map->ops->map_delete_elem(map, key); 1818 rcu_read_unlock(); 1819 bpf_enable_instrumentation(); 1820 if (err) 1821 break; 1822 cond_resched(); 1823 } 1824 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1825 err = -EFAULT; 1826 1827 kvfree(key); 1828 1829 return err; 1830 } 1831 1832 int generic_map_update_batch(struct bpf_map *map, struct file *map_file, 1833 const union bpf_attr *attr, 1834 union bpf_attr __user *uattr) 1835 { 1836 void __user *values = u64_to_user_ptr(attr->batch.values); 1837 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1838 u32 value_size, cp, max_count; 1839 void *key, *value; 1840 int err = 0; 1841 1842 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1843 return -EINVAL; 1844 1845 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1846 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1847 return -EINVAL; 1848 } 1849 1850 value_size = bpf_map_value_size(map); 1851 1852 max_count = attr->batch.count; 1853 if (!max_count) 1854 return 0; 1855 1856 if (put_user(0, &uattr->batch.count)) 1857 return -EFAULT; 1858 1859 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1860 if (!key) 1861 return -ENOMEM; 1862 1863 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1864 if (!value) { 1865 kvfree(key); 1866 return -ENOMEM; 1867 } 1868 1869 for (cp = 0; cp < max_count; cp++) { 1870 err = -EFAULT; 1871 if (copy_from_user(key, keys + cp * map->key_size, 1872 map->key_size) || 1873 copy_from_user(value, values + cp * value_size, value_size)) 1874 break; 1875 1876 err = bpf_map_update_value(map, map_file, key, value, 1877 attr->batch.elem_flags); 1878 1879 if (err) 1880 break; 1881 cond_resched(); 1882 } 1883 1884 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1885 err = -EFAULT; 1886 1887 kvfree(value); 1888 kvfree(key); 1889 1890 return err; 1891 } 1892 1893 #define MAP_LOOKUP_RETRIES 3 1894 1895 int generic_map_lookup_batch(struct bpf_map *map, 1896 const union bpf_attr *attr, 1897 union bpf_attr __user *uattr) 1898 { 1899 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 1900 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 1901 void __user *values = u64_to_user_ptr(attr->batch.values); 1902 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1903 void *buf, *buf_prevkey, *prev_key, *key, *value; 1904 int err, retry = MAP_LOOKUP_RETRIES; 1905 u32 value_size, cp, max_count; 1906 1907 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1908 return -EINVAL; 1909 1910 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1911 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) 1912 return -EINVAL; 1913 1914 value_size = bpf_map_value_size(map); 1915 1916 max_count = attr->batch.count; 1917 if (!max_count) 1918 return 0; 1919 1920 if (put_user(0, &uattr->batch.count)) 1921 return -EFAULT; 1922 1923 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1924 if (!buf_prevkey) 1925 return -ENOMEM; 1926 1927 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 1928 if (!buf) { 1929 kvfree(buf_prevkey); 1930 return -ENOMEM; 1931 } 1932 1933 err = -EFAULT; 1934 prev_key = NULL; 1935 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 1936 goto free_buf; 1937 key = buf; 1938 value = key + map->key_size; 1939 if (ubatch) 1940 prev_key = buf_prevkey; 1941 1942 for (cp = 0; cp < max_count;) { 1943 rcu_read_lock(); 1944 err = map->ops->map_get_next_key(map, prev_key, key); 1945 rcu_read_unlock(); 1946 if (err) 1947 break; 1948 err = bpf_map_copy_value(map, key, value, 1949 attr->batch.elem_flags); 1950 1951 if (err == -ENOENT) { 1952 if (retry) { 1953 retry--; 1954 continue; 1955 } 1956 err = -EINTR; 1957 break; 1958 } 1959 1960 if (err) 1961 goto free_buf; 1962 1963 if (copy_to_user(keys + cp * map->key_size, key, 1964 map->key_size)) { 1965 err = -EFAULT; 1966 goto free_buf; 1967 } 1968 if (copy_to_user(values + cp * value_size, value, value_size)) { 1969 err = -EFAULT; 1970 goto free_buf; 1971 } 1972 1973 if (!prev_key) 1974 prev_key = buf_prevkey; 1975 1976 swap(prev_key, key); 1977 retry = MAP_LOOKUP_RETRIES; 1978 cp++; 1979 cond_resched(); 1980 } 1981 1982 if (err == -EFAULT) 1983 goto free_buf; 1984 1985 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 1986 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 1987 err = -EFAULT; 1988 1989 free_buf: 1990 kvfree(buf_prevkey); 1991 kvfree(buf); 1992 return err; 1993 } 1994 1995 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 1996 1997 static int map_lookup_and_delete_elem(union bpf_attr *attr) 1998 { 1999 void __user *ukey = u64_to_user_ptr(attr->key); 2000 void __user *uvalue = u64_to_user_ptr(attr->value); 2001 int ufd = attr->map_fd; 2002 struct bpf_map *map; 2003 void *key, *value; 2004 u32 value_size; 2005 struct fd f; 2006 int err; 2007 2008 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 2009 return -EINVAL; 2010 2011 if (attr->flags & ~BPF_F_LOCK) 2012 return -EINVAL; 2013 2014 f = fdget(ufd); 2015 map = __bpf_map_get(f); 2016 if (IS_ERR(map)) 2017 return PTR_ERR(map); 2018 bpf_map_write_active_inc(map); 2019 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 2020 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 2021 err = -EPERM; 2022 goto err_put; 2023 } 2024 2025 if (attr->flags && 2026 (map->map_type == BPF_MAP_TYPE_QUEUE || 2027 map->map_type == BPF_MAP_TYPE_STACK)) { 2028 err = -EINVAL; 2029 goto err_put; 2030 } 2031 2032 if ((attr->flags & BPF_F_LOCK) && 2033 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2034 err = -EINVAL; 2035 goto err_put; 2036 } 2037 2038 key = __bpf_copy_key(ukey, map->key_size); 2039 if (IS_ERR(key)) { 2040 err = PTR_ERR(key); 2041 goto err_put; 2042 } 2043 2044 value_size = bpf_map_value_size(map); 2045 2046 err = -ENOMEM; 2047 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2048 if (!value) 2049 goto free_key; 2050 2051 err = -ENOTSUPP; 2052 if (map->map_type == BPF_MAP_TYPE_QUEUE || 2053 map->map_type == BPF_MAP_TYPE_STACK) { 2054 err = map->ops->map_pop_elem(map, value); 2055 } else if (map->map_type == BPF_MAP_TYPE_HASH || 2056 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 2057 map->map_type == BPF_MAP_TYPE_LRU_HASH || 2058 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 2059 if (!bpf_map_is_offloaded(map)) { 2060 bpf_disable_instrumentation(); 2061 rcu_read_lock(); 2062 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 2063 rcu_read_unlock(); 2064 bpf_enable_instrumentation(); 2065 } 2066 } 2067 2068 if (err) 2069 goto free_value; 2070 2071 if (copy_to_user(uvalue, value, value_size) != 0) { 2072 err = -EFAULT; 2073 goto free_value; 2074 } 2075 2076 err = 0; 2077 2078 free_value: 2079 kvfree(value); 2080 free_key: 2081 kvfree(key); 2082 err_put: 2083 bpf_map_write_active_dec(map); 2084 fdput(f); 2085 return err; 2086 } 2087 2088 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 2089 2090 static int map_freeze(const union bpf_attr *attr) 2091 { 2092 int err = 0, ufd = attr->map_fd; 2093 struct bpf_map *map; 2094 struct fd f; 2095 2096 if (CHECK_ATTR(BPF_MAP_FREEZE)) 2097 return -EINVAL; 2098 2099 f = fdget(ufd); 2100 map = __bpf_map_get(f); 2101 if (IS_ERR(map)) 2102 return PTR_ERR(map); 2103 2104 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) { 2105 fdput(f); 2106 return -ENOTSUPP; 2107 } 2108 2109 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 2110 fdput(f); 2111 return -EPERM; 2112 } 2113 2114 mutex_lock(&map->freeze_mutex); 2115 if (bpf_map_write_active(map)) { 2116 err = -EBUSY; 2117 goto err_put; 2118 } 2119 if (READ_ONCE(map->frozen)) { 2120 err = -EBUSY; 2121 goto err_put; 2122 } 2123 2124 WRITE_ONCE(map->frozen, true); 2125 err_put: 2126 mutex_unlock(&map->freeze_mutex); 2127 fdput(f); 2128 return err; 2129 } 2130 2131 static const struct bpf_prog_ops * const bpf_prog_types[] = { 2132 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 2133 [_id] = & _name ## _prog_ops, 2134 #define BPF_MAP_TYPE(_id, _ops) 2135 #define BPF_LINK_TYPE(_id, _name) 2136 #include <linux/bpf_types.h> 2137 #undef BPF_PROG_TYPE 2138 #undef BPF_MAP_TYPE 2139 #undef BPF_LINK_TYPE 2140 }; 2141 2142 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 2143 { 2144 const struct bpf_prog_ops *ops; 2145 2146 if (type >= ARRAY_SIZE(bpf_prog_types)) 2147 return -EINVAL; 2148 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 2149 ops = bpf_prog_types[type]; 2150 if (!ops) 2151 return -EINVAL; 2152 2153 if (!bpf_prog_is_offloaded(prog->aux)) 2154 prog->aux->ops = ops; 2155 else 2156 prog->aux->ops = &bpf_offload_prog_ops; 2157 prog->type = type; 2158 return 0; 2159 } 2160 2161 enum bpf_audit { 2162 BPF_AUDIT_LOAD, 2163 BPF_AUDIT_UNLOAD, 2164 BPF_AUDIT_MAX, 2165 }; 2166 2167 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 2168 [BPF_AUDIT_LOAD] = "LOAD", 2169 [BPF_AUDIT_UNLOAD] = "UNLOAD", 2170 }; 2171 2172 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 2173 { 2174 struct audit_context *ctx = NULL; 2175 struct audit_buffer *ab; 2176 2177 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 2178 return; 2179 if (audit_enabled == AUDIT_OFF) 2180 return; 2181 if (!in_irq() && !irqs_disabled()) 2182 ctx = audit_context(); 2183 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 2184 if (unlikely(!ab)) 2185 return; 2186 audit_log_format(ab, "prog-id=%u op=%s", 2187 prog->aux->id, bpf_audit_str[op]); 2188 audit_log_end(ab); 2189 } 2190 2191 static int bpf_prog_alloc_id(struct bpf_prog *prog) 2192 { 2193 int id; 2194 2195 idr_preload(GFP_KERNEL); 2196 spin_lock_bh(&prog_idr_lock); 2197 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 2198 if (id > 0) 2199 prog->aux->id = id; 2200 spin_unlock_bh(&prog_idr_lock); 2201 idr_preload_end(); 2202 2203 /* id is in [1, INT_MAX) */ 2204 if (WARN_ON_ONCE(!id)) 2205 return -ENOSPC; 2206 2207 return id > 0 ? 0 : id; 2208 } 2209 2210 void bpf_prog_free_id(struct bpf_prog *prog) 2211 { 2212 unsigned long flags; 2213 2214 /* cBPF to eBPF migrations are currently not in the idr store. 2215 * Offloaded programs are removed from the store when their device 2216 * disappears - even if someone grabs an fd to them they are unusable, 2217 * simply waiting for refcnt to drop to be freed. 2218 */ 2219 if (!prog->aux->id) 2220 return; 2221 2222 spin_lock_irqsave(&prog_idr_lock, flags); 2223 idr_remove(&prog_idr, prog->aux->id); 2224 prog->aux->id = 0; 2225 spin_unlock_irqrestore(&prog_idr_lock, flags); 2226 } 2227 2228 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 2229 { 2230 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 2231 2232 kvfree(aux->func_info); 2233 kfree(aux->func_info_aux); 2234 free_uid(aux->user); 2235 security_bpf_prog_free(aux->prog); 2236 bpf_prog_free(aux->prog); 2237 } 2238 2239 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 2240 { 2241 bpf_prog_kallsyms_del_all(prog); 2242 btf_put(prog->aux->btf); 2243 module_put(prog->aux->mod); 2244 kvfree(prog->aux->jited_linfo); 2245 kvfree(prog->aux->linfo); 2246 kfree(prog->aux->kfunc_tab); 2247 if (prog->aux->attach_btf) 2248 btf_put(prog->aux->attach_btf); 2249 2250 if (deferred) { 2251 if (prog->sleepable) 2252 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 2253 else 2254 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 2255 } else { 2256 __bpf_prog_put_rcu(&prog->aux->rcu); 2257 } 2258 } 2259 2260 static void bpf_prog_put_deferred(struct work_struct *work) 2261 { 2262 struct bpf_prog_aux *aux; 2263 struct bpf_prog *prog; 2264 2265 aux = container_of(work, struct bpf_prog_aux, work); 2266 prog = aux->prog; 2267 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 2268 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 2269 bpf_prog_free_id(prog); 2270 __bpf_prog_put_noref(prog, true); 2271 } 2272 2273 static void __bpf_prog_put(struct bpf_prog *prog) 2274 { 2275 struct bpf_prog_aux *aux = prog->aux; 2276 2277 if (atomic64_dec_and_test(&aux->refcnt)) { 2278 if (in_irq() || irqs_disabled()) { 2279 INIT_WORK(&aux->work, bpf_prog_put_deferred); 2280 schedule_work(&aux->work); 2281 } else { 2282 bpf_prog_put_deferred(&aux->work); 2283 } 2284 } 2285 } 2286 2287 void bpf_prog_put(struct bpf_prog *prog) 2288 { 2289 __bpf_prog_put(prog); 2290 } 2291 EXPORT_SYMBOL_GPL(bpf_prog_put); 2292 2293 static int bpf_prog_release(struct inode *inode, struct file *filp) 2294 { 2295 struct bpf_prog *prog = filp->private_data; 2296 2297 bpf_prog_put(prog); 2298 return 0; 2299 } 2300 2301 struct bpf_prog_kstats { 2302 u64 nsecs; 2303 u64 cnt; 2304 u64 misses; 2305 }; 2306 2307 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) 2308 { 2309 struct bpf_prog_stats *stats; 2310 unsigned int flags; 2311 2312 stats = this_cpu_ptr(prog->stats); 2313 flags = u64_stats_update_begin_irqsave(&stats->syncp); 2314 u64_stats_inc(&stats->misses); 2315 u64_stats_update_end_irqrestore(&stats->syncp, flags); 2316 } 2317 2318 static void bpf_prog_get_stats(const struct bpf_prog *prog, 2319 struct bpf_prog_kstats *stats) 2320 { 2321 u64 nsecs = 0, cnt = 0, misses = 0; 2322 int cpu; 2323 2324 for_each_possible_cpu(cpu) { 2325 const struct bpf_prog_stats *st; 2326 unsigned int start; 2327 u64 tnsecs, tcnt, tmisses; 2328 2329 st = per_cpu_ptr(prog->stats, cpu); 2330 do { 2331 start = u64_stats_fetch_begin(&st->syncp); 2332 tnsecs = u64_stats_read(&st->nsecs); 2333 tcnt = u64_stats_read(&st->cnt); 2334 tmisses = u64_stats_read(&st->misses); 2335 } while (u64_stats_fetch_retry(&st->syncp, start)); 2336 nsecs += tnsecs; 2337 cnt += tcnt; 2338 misses += tmisses; 2339 } 2340 stats->nsecs = nsecs; 2341 stats->cnt = cnt; 2342 stats->misses = misses; 2343 } 2344 2345 #ifdef CONFIG_PROC_FS 2346 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 2347 { 2348 const struct bpf_prog *prog = filp->private_data; 2349 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2350 struct bpf_prog_kstats stats; 2351 2352 bpf_prog_get_stats(prog, &stats); 2353 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2354 seq_printf(m, 2355 "prog_type:\t%u\n" 2356 "prog_jited:\t%u\n" 2357 "prog_tag:\t%s\n" 2358 "memlock:\t%llu\n" 2359 "prog_id:\t%u\n" 2360 "run_time_ns:\t%llu\n" 2361 "run_cnt:\t%llu\n" 2362 "recursion_misses:\t%llu\n" 2363 "verified_insns:\t%u\n", 2364 prog->type, 2365 prog->jited, 2366 prog_tag, 2367 prog->pages * 1ULL << PAGE_SHIFT, 2368 prog->aux->id, 2369 stats.nsecs, 2370 stats.cnt, 2371 stats.misses, 2372 prog->aux->verified_insns); 2373 } 2374 #endif 2375 2376 const struct file_operations bpf_prog_fops = { 2377 #ifdef CONFIG_PROC_FS 2378 .show_fdinfo = bpf_prog_show_fdinfo, 2379 #endif 2380 .release = bpf_prog_release, 2381 .read = bpf_dummy_read, 2382 .write = bpf_dummy_write, 2383 }; 2384 2385 int bpf_prog_new_fd(struct bpf_prog *prog) 2386 { 2387 int ret; 2388 2389 ret = security_bpf_prog(prog); 2390 if (ret < 0) 2391 return ret; 2392 2393 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 2394 O_RDWR | O_CLOEXEC); 2395 } 2396 2397 static struct bpf_prog *____bpf_prog_get(struct fd f) 2398 { 2399 if (!f.file) 2400 return ERR_PTR(-EBADF); 2401 if (f.file->f_op != &bpf_prog_fops) { 2402 fdput(f); 2403 return ERR_PTR(-EINVAL); 2404 } 2405 2406 return f.file->private_data; 2407 } 2408 2409 void bpf_prog_add(struct bpf_prog *prog, int i) 2410 { 2411 atomic64_add(i, &prog->aux->refcnt); 2412 } 2413 EXPORT_SYMBOL_GPL(bpf_prog_add); 2414 2415 void bpf_prog_sub(struct bpf_prog *prog, int i) 2416 { 2417 /* Only to be used for undoing previous bpf_prog_add() in some 2418 * error path. We still know that another entity in our call 2419 * path holds a reference to the program, thus atomic_sub() can 2420 * be safely used in such cases! 2421 */ 2422 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 2423 } 2424 EXPORT_SYMBOL_GPL(bpf_prog_sub); 2425 2426 void bpf_prog_inc(struct bpf_prog *prog) 2427 { 2428 atomic64_inc(&prog->aux->refcnt); 2429 } 2430 EXPORT_SYMBOL_GPL(bpf_prog_inc); 2431 2432 /* prog_idr_lock should have been held */ 2433 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 2434 { 2435 int refold; 2436 2437 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 2438 2439 if (!refold) 2440 return ERR_PTR(-ENOENT); 2441 2442 return prog; 2443 } 2444 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 2445 2446 bool bpf_prog_get_ok(struct bpf_prog *prog, 2447 enum bpf_prog_type *attach_type, bool attach_drv) 2448 { 2449 /* not an attachment, just a refcount inc, always allow */ 2450 if (!attach_type) 2451 return true; 2452 2453 if (prog->type != *attach_type) 2454 return false; 2455 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) 2456 return false; 2457 2458 return true; 2459 } 2460 2461 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 2462 bool attach_drv) 2463 { 2464 struct fd f = fdget(ufd); 2465 struct bpf_prog *prog; 2466 2467 prog = ____bpf_prog_get(f); 2468 if (IS_ERR(prog)) 2469 return prog; 2470 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) { 2471 prog = ERR_PTR(-EINVAL); 2472 goto out; 2473 } 2474 2475 bpf_prog_inc(prog); 2476 out: 2477 fdput(f); 2478 return prog; 2479 } 2480 2481 struct bpf_prog *bpf_prog_get(u32 ufd) 2482 { 2483 return __bpf_prog_get(ufd, NULL, false); 2484 } 2485 2486 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2487 bool attach_drv) 2488 { 2489 return __bpf_prog_get(ufd, &type, attach_drv); 2490 } 2491 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2492 2493 /* Initially all BPF programs could be loaded w/o specifying 2494 * expected_attach_type. Later for some of them specifying expected_attach_type 2495 * at load time became required so that program could be validated properly. 2496 * Programs of types that are allowed to be loaded both w/ and w/o (for 2497 * backward compatibility) expected_attach_type, should have the default attach 2498 * type assigned to expected_attach_type for the latter case, so that it can be 2499 * validated later at attach time. 2500 * 2501 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2502 * prog type requires it but has some attach types that have to be backward 2503 * compatible. 2504 */ 2505 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2506 { 2507 switch (attr->prog_type) { 2508 case BPF_PROG_TYPE_CGROUP_SOCK: 2509 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2510 * exist so checking for non-zero is the way to go here. 2511 */ 2512 if (!attr->expected_attach_type) 2513 attr->expected_attach_type = 2514 BPF_CGROUP_INET_SOCK_CREATE; 2515 break; 2516 case BPF_PROG_TYPE_SK_REUSEPORT: 2517 if (!attr->expected_attach_type) 2518 attr->expected_attach_type = 2519 BPF_SK_REUSEPORT_SELECT; 2520 break; 2521 } 2522 } 2523 2524 static int 2525 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2526 enum bpf_attach_type expected_attach_type, 2527 struct btf *attach_btf, u32 btf_id, 2528 struct bpf_prog *dst_prog) 2529 { 2530 if (btf_id) { 2531 if (btf_id > BTF_MAX_TYPE) 2532 return -EINVAL; 2533 2534 if (!attach_btf && !dst_prog) 2535 return -EINVAL; 2536 2537 switch (prog_type) { 2538 case BPF_PROG_TYPE_TRACING: 2539 case BPF_PROG_TYPE_LSM: 2540 case BPF_PROG_TYPE_STRUCT_OPS: 2541 case BPF_PROG_TYPE_EXT: 2542 break; 2543 default: 2544 return -EINVAL; 2545 } 2546 } 2547 2548 if (attach_btf && (!btf_id || dst_prog)) 2549 return -EINVAL; 2550 2551 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2552 prog_type != BPF_PROG_TYPE_EXT) 2553 return -EINVAL; 2554 2555 switch (prog_type) { 2556 case BPF_PROG_TYPE_CGROUP_SOCK: 2557 switch (expected_attach_type) { 2558 case BPF_CGROUP_INET_SOCK_CREATE: 2559 case BPF_CGROUP_INET_SOCK_RELEASE: 2560 case BPF_CGROUP_INET4_POST_BIND: 2561 case BPF_CGROUP_INET6_POST_BIND: 2562 return 0; 2563 default: 2564 return -EINVAL; 2565 } 2566 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2567 switch (expected_attach_type) { 2568 case BPF_CGROUP_INET4_BIND: 2569 case BPF_CGROUP_INET6_BIND: 2570 case BPF_CGROUP_INET4_CONNECT: 2571 case BPF_CGROUP_INET6_CONNECT: 2572 case BPF_CGROUP_UNIX_CONNECT: 2573 case BPF_CGROUP_INET4_GETPEERNAME: 2574 case BPF_CGROUP_INET6_GETPEERNAME: 2575 case BPF_CGROUP_UNIX_GETPEERNAME: 2576 case BPF_CGROUP_INET4_GETSOCKNAME: 2577 case BPF_CGROUP_INET6_GETSOCKNAME: 2578 case BPF_CGROUP_UNIX_GETSOCKNAME: 2579 case BPF_CGROUP_UDP4_SENDMSG: 2580 case BPF_CGROUP_UDP6_SENDMSG: 2581 case BPF_CGROUP_UNIX_SENDMSG: 2582 case BPF_CGROUP_UDP4_RECVMSG: 2583 case BPF_CGROUP_UDP6_RECVMSG: 2584 case BPF_CGROUP_UNIX_RECVMSG: 2585 return 0; 2586 default: 2587 return -EINVAL; 2588 } 2589 case BPF_PROG_TYPE_CGROUP_SKB: 2590 switch (expected_attach_type) { 2591 case BPF_CGROUP_INET_INGRESS: 2592 case BPF_CGROUP_INET_EGRESS: 2593 return 0; 2594 default: 2595 return -EINVAL; 2596 } 2597 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2598 switch (expected_attach_type) { 2599 case BPF_CGROUP_SETSOCKOPT: 2600 case BPF_CGROUP_GETSOCKOPT: 2601 return 0; 2602 default: 2603 return -EINVAL; 2604 } 2605 case BPF_PROG_TYPE_SK_LOOKUP: 2606 if (expected_attach_type == BPF_SK_LOOKUP) 2607 return 0; 2608 return -EINVAL; 2609 case BPF_PROG_TYPE_SK_REUSEPORT: 2610 switch (expected_attach_type) { 2611 case BPF_SK_REUSEPORT_SELECT: 2612 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2613 return 0; 2614 default: 2615 return -EINVAL; 2616 } 2617 case BPF_PROG_TYPE_NETFILTER: 2618 if (expected_attach_type == BPF_NETFILTER) 2619 return 0; 2620 return -EINVAL; 2621 case BPF_PROG_TYPE_SYSCALL: 2622 case BPF_PROG_TYPE_EXT: 2623 if (expected_attach_type) 2624 return -EINVAL; 2625 fallthrough; 2626 default: 2627 return 0; 2628 } 2629 } 2630 2631 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2632 { 2633 switch (prog_type) { 2634 case BPF_PROG_TYPE_SCHED_CLS: 2635 case BPF_PROG_TYPE_SCHED_ACT: 2636 case BPF_PROG_TYPE_XDP: 2637 case BPF_PROG_TYPE_LWT_IN: 2638 case BPF_PROG_TYPE_LWT_OUT: 2639 case BPF_PROG_TYPE_LWT_XMIT: 2640 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2641 case BPF_PROG_TYPE_SK_SKB: 2642 case BPF_PROG_TYPE_SK_MSG: 2643 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2644 case BPF_PROG_TYPE_CGROUP_DEVICE: 2645 case BPF_PROG_TYPE_CGROUP_SOCK: 2646 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2647 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2648 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2649 case BPF_PROG_TYPE_SOCK_OPS: 2650 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2651 case BPF_PROG_TYPE_NETFILTER: 2652 return true; 2653 case BPF_PROG_TYPE_CGROUP_SKB: 2654 /* always unpriv */ 2655 case BPF_PROG_TYPE_SK_REUSEPORT: 2656 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2657 default: 2658 return false; 2659 } 2660 } 2661 2662 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2663 { 2664 switch (prog_type) { 2665 case BPF_PROG_TYPE_KPROBE: 2666 case BPF_PROG_TYPE_TRACEPOINT: 2667 case BPF_PROG_TYPE_PERF_EVENT: 2668 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2669 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2670 case BPF_PROG_TYPE_TRACING: 2671 case BPF_PROG_TYPE_LSM: 2672 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2673 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2674 return true; 2675 default: 2676 return false; 2677 } 2678 } 2679 2680 /* last field in 'union bpf_attr' used by this command */ 2681 #define BPF_PROG_LOAD_LAST_FIELD prog_token_fd 2682 2683 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) 2684 { 2685 enum bpf_prog_type type = attr->prog_type; 2686 struct bpf_prog *prog, *dst_prog = NULL; 2687 struct btf *attach_btf = NULL; 2688 struct bpf_token *token = NULL; 2689 bool bpf_cap; 2690 int err; 2691 char license[128]; 2692 2693 if (CHECK_ATTR(BPF_PROG_LOAD)) 2694 return -EINVAL; 2695 2696 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2697 BPF_F_ANY_ALIGNMENT | 2698 BPF_F_TEST_STATE_FREQ | 2699 BPF_F_SLEEPABLE | 2700 BPF_F_TEST_RND_HI32 | 2701 BPF_F_XDP_HAS_FRAGS | 2702 BPF_F_XDP_DEV_BOUND_ONLY | 2703 BPF_F_TEST_REG_INVARIANTS | 2704 BPF_F_TOKEN_FD)) 2705 return -EINVAL; 2706 2707 bpf_prog_load_fixup_attach_type(attr); 2708 2709 if (attr->prog_flags & BPF_F_TOKEN_FD) { 2710 token = bpf_token_get_from_fd(attr->prog_token_fd); 2711 if (IS_ERR(token)) 2712 return PTR_ERR(token); 2713 /* if current token doesn't grant prog loading permissions, 2714 * then we can't use this token, so ignore it and rely on 2715 * system-wide capabilities checks 2716 */ 2717 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || 2718 !bpf_token_allow_prog_type(token, attr->prog_type, 2719 attr->expected_attach_type)) { 2720 bpf_token_put(token); 2721 token = NULL; 2722 } 2723 } 2724 2725 bpf_cap = bpf_token_capable(token, CAP_BPF); 2726 err = -EPERM; 2727 2728 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2729 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2730 !bpf_cap) 2731 goto put_token; 2732 2733 /* Intent here is for unprivileged_bpf_disabled to block BPF program 2734 * creation for unprivileged users; other actions depend 2735 * on fd availability and access to bpffs, so are dependent on 2736 * object creation success. Even with unprivileged BPF disabled, 2737 * capability checks are still carried out for these 2738 * and other operations. 2739 */ 2740 if (sysctl_unprivileged_bpf_disabled && !bpf_cap) 2741 goto put_token; 2742 2743 if (attr->insn_cnt == 0 || 2744 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { 2745 err = -E2BIG; 2746 goto put_token; 2747 } 2748 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2749 type != BPF_PROG_TYPE_CGROUP_SKB && 2750 !bpf_cap) 2751 goto put_token; 2752 2753 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) 2754 goto put_token; 2755 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) 2756 goto put_token; 2757 2758 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2759 * or btf, we need to check which one it is 2760 */ 2761 if (attr->attach_prog_fd) { 2762 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2763 if (IS_ERR(dst_prog)) { 2764 dst_prog = NULL; 2765 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2766 if (IS_ERR(attach_btf)) { 2767 err = -EINVAL; 2768 goto put_token; 2769 } 2770 if (!btf_is_kernel(attach_btf)) { 2771 /* attaching through specifying bpf_prog's BTF 2772 * objects directly might be supported eventually 2773 */ 2774 btf_put(attach_btf); 2775 err = -ENOTSUPP; 2776 goto put_token; 2777 } 2778 } 2779 } else if (attr->attach_btf_id) { 2780 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2781 attach_btf = bpf_get_btf_vmlinux(); 2782 if (IS_ERR(attach_btf)) { 2783 err = PTR_ERR(attach_btf); 2784 goto put_token; 2785 } 2786 if (!attach_btf) { 2787 err = -EINVAL; 2788 goto put_token; 2789 } 2790 btf_get(attach_btf); 2791 } 2792 2793 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2794 attach_btf, attr->attach_btf_id, 2795 dst_prog)) { 2796 if (dst_prog) 2797 bpf_prog_put(dst_prog); 2798 if (attach_btf) 2799 btf_put(attach_btf); 2800 err = -EINVAL; 2801 goto put_token; 2802 } 2803 2804 /* plain bpf_prog allocation */ 2805 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2806 if (!prog) { 2807 if (dst_prog) 2808 bpf_prog_put(dst_prog); 2809 if (attach_btf) 2810 btf_put(attach_btf); 2811 err = -EINVAL; 2812 goto put_token; 2813 } 2814 2815 prog->expected_attach_type = attr->expected_attach_type; 2816 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); 2817 prog->aux->attach_btf = attach_btf; 2818 prog->aux->attach_btf_id = attr->attach_btf_id; 2819 prog->aux->dst_prog = dst_prog; 2820 prog->aux->dev_bound = !!attr->prog_ifindex; 2821 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 2822 2823 /* move token into prog->aux, reuse taken refcnt */ 2824 prog->aux->token = token; 2825 token = NULL; 2826 2827 prog->aux->user = get_current_user(); 2828 prog->len = attr->insn_cnt; 2829 2830 err = -EFAULT; 2831 if (copy_from_bpfptr(prog->insns, 2832 make_bpfptr(attr->insns, uattr.is_kernel), 2833 bpf_prog_insn_size(prog)) != 0) 2834 goto free_prog; 2835 /* copy eBPF program license from user space */ 2836 if (strncpy_from_bpfptr(license, 2837 make_bpfptr(attr->license, uattr.is_kernel), 2838 sizeof(license) - 1) < 0) 2839 goto free_prog; 2840 license[sizeof(license) - 1] = 0; 2841 2842 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2843 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; 2844 2845 prog->orig_prog = NULL; 2846 prog->jited = 0; 2847 2848 atomic64_set(&prog->aux->refcnt, 1); 2849 2850 if (bpf_prog_is_dev_bound(prog->aux)) { 2851 err = bpf_prog_dev_bound_init(prog, attr); 2852 if (err) 2853 goto free_prog; 2854 } 2855 2856 if (type == BPF_PROG_TYPE_EXT && dst_prog && 2857 bpf_prog_is_dev_bound(dst_prog->aux)) { 2858 err = bpf_prog_dev_bound_inherit(prog, dst_prog); 2859 if (err) 2860 goto free_prog; 2861 } 2862 2863 /* 2864 * Bookkeeping for managing the program attachment chain. 2865 * 2866 * It might be tempting to set attach_tracing_prog flag at the attachment 2867 * time, but this will not prevent from loading bunch of tracing prog 2868 * first, then attach them one to another. 2869 * 2870 * The flag attach_tracing_prog is set for the whole program lifecycle, and 2871 * doesn't have to be cleared in bpf_tracing_link_release, since tracing 2872 * programs cannot change attachment target. 2873 */ 2874 if (type == BPF_PROG_TYPE_TRACING && dst_prog && 2875 dst_prog->type == BPF_PROG_TYPE_TRACING) { 2876 prog->aux->attach_tracing_prog = true; 2877 } 2878 2879 /* find program type: socket_filter vs tracing_filter */ 2880 err = find_prog_type(type, prog); 2881 if (err < 0) 2882 goto free_prog; 2883 2884 prog->aux->load_time = ktime_get_boottime_ns(); 2885 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2886 sizeof(attr->prog_name)); 2887 if (err < 0) 2888 goto free_prog; 2889 2890 err = security_bpf_prog_load(prog, attr, token); 2891 if (err) 2892 goto free_prog_sec; 2893 2894 /* run eBPF verifier */ 2895 err = bpf_check(&prog, attr, uattr, uattr_size); 2896 if (err < 0) 2897 goto free_used_maps; 2898 2899 prog = bpf_prog_select_runtime(prog, &err); 2900 if (err < 0) 2901 goto free_used_maps; 2902 2903 err = bpf_prog_alloc_id(prog); 2904 if (err) 2905 goto free_used_maps; 2906 2907 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2908 * effectively publicly exposed. However, retrieving via 2909 * bpf_prog_get_fd_by_id() will take another reference, 2910 * therefore it cannot be gone underneath us. 2911 * 2912 * Only for the time /after/ successful bpf_prog_new_fd() 2913 * and before returning to userspace, we might just hold 2914 * one reference and any parallel close on that fd could 2915 * rip everything out. Hence, below notifications must 2916 * happen before bpf_prog_new_fd(). 2917 * 2918 * Also, any failure handling from this point onwards must 2919 * be using bpf_prog_put() given the program is exposed. 2920 */ 2921 bpf_prog_kallsyms_add(prog); 2922 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 2923 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 2924 2925 err = bpf_prog_new_fd(prog); 2926 if (err < 0) 2927 bpf_prog_put(prog); 2928 return err; 2929 2930 free_used_maps: 2931 /* In case we have subprogs, we need to wait for a grace 2932 * period before we can tear down JIT memory since symbols 2933 * are already exposed under kallsyms. 2934 */ 2935 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); 2936 return err; 2937 2938 free_prog_sec: 2939 security_bpf_prog_free(prog); 2940 free_prog: 2941 free_uid(prog->aux->user); 2942 if (prog->aux->attach_btf) 2943 btf_put(prog->aux->attach_btf); 2944 bpf_prog_free(prog); 2945 put_token: 2946 bpf_token_put(token); 2947 return err; 2948 } 2949 2950 #define BPF_OBJ_LAST_FIELD path_fd 2951 2952 static int bpf_obj_pin(const union bpf_attr *attr) 2953 { 2954 int path_fd; 2955 2956 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) 2957 return -EINVAL; 2958 2959 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 2960 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 2961 return -EINVAL; 2962 2963 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 2964 return bpf_obj_pin_user(attr->bpf_fd, path_fd, 2965 u64_to_user_ptr(attr->pathname)); 2966 } 2967 2968 static int bpf_obj_get(const union bpf_attr *attr) 2969 { 2970 int path_fd; 2971 2972 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 2973 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) 2974 return -EINVAL; 2975 2976 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 2977 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 2978 return -EINVAL; 2979 2980 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 2981 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), 2982 attr->file_flags); 2983 } 2984 2985 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 2986 const struct bpf_link_ops *ops, struct bpf_prog *prog) 2987 { 2988 atomic64_set(&link->refcnt, 1); 2989 link->type = type; 2990 link->id = 0; 2991 link->ops = ops; 2992 link->prog = prog; 2993 } 2994 2995 static void bpf_link_free_id(int id) 2996 { 2997 if (!id) 2998 return; 2999 3000 spin_lock_bh(&link_idr_lock); 3001 idr_remove(&link_idr, id); 3002 spin_unlock_bh(&link_idr_lock); 3003 } 3004 3005 /* Clean up bpf_link and corresponding anon_inode file and FD. After 3006 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 3007 * anon_inode's release() call. This helper marks bpf_link as 3008 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 3009 * is not decremented, it's the responsibility of a calling code that failed 3010 * to complete bpf_link initialization. 3011 * This helper eventually calls link's dealloc callback, but does not call 3012 * link's release callback. 3013 */ 3014 void bpf_link_cleanup(struct bpf_link_primer *primer) 3015 { 3016 primer->link->prog = NULL; 3017 bpf_link_free_id(primer->id); 3018 fput(primer->file); 3019 put_unused_fd(primer->fd); 3020 } 3021 3022 void bpf_link_inc(struct bpf_link *link) 3023 { 3024 atomic64_inc(&link->refcnt); 3025 } 3026 3027 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) 3028 { 3029 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); 3030 3031 /* free bpf_link and its containing memory */ 3032 link->ops->dealloc_deferred(link); 3033 } 3034 3035 static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu) 3036 { 3037 if (rcu_trace_implies_rcu_gp()) 3038 bpf_link_defer_dealloc_rcu_gp(rcu); 3039 else 3040 call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp); 3041 } 3042 3043 /* bpf_link_free is guaranteed to be called from process context */ 3044 static void bpf_link_free(struct bpf_link *link) 3045 { 3046 bool sleepable = false; 3047 3048 bpf_link_free_id(link->id); 3049 if (link->prog) { 3050 sleepable = link->prog->sleepable; 3051 /* detach BPF program, clean up used resources */ 3052 link->ops->release(link); 3053 bpf_prog_put(link->prog); 3054 } 3055 if (link->ops->dealloc_deferred) { 3056 /* schedule BPF link deallocation; if underlying BPF program 3057 * is sleepable, we need to first wait for RCU tasks trace 3058 * sync, then go through "classic" RCU grace period 3059 */ 3060 if (sleepable) 3061 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp); 3062 else 3063 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3064 } 3065 if (link->ops->dealloc) 3066 link->ops->dealloc(link); 3067 } 3068 3069 static void bpf_link_put_deferred(struct work_struct *work) 3070 { 3071 struct bpf_link *link = container_of(work, struct bpf_link, work); 3072 3073 bpf_link_free(link); 3074 } 3075 3076 /* bpf_link_put might be called from atomic context. It needs to be called 3077 * from sleepable context in order to acquire sleeping locks during the process. 3078 */ 3079 void bpf_link_put(struct bpf_link *link) 3080 { 3081 if (!atomic64_dec_and_test(&link->refcnt)) 3082 return; 3083 3084 INIT_WORK(&link->work, bpf_link_put_deferred); 3085 schedule_work(&link->work); 3086 } 3087 EXPORT_SYMBOL(bpf_link_put); 3088 3089 static void bpf_link_put_direct(struct bpf_link *link) 3090 { 3091 if (!atomic64_dec_and_test(&link->refcnt)) 3092 return; 3093 bpf_link_free(link); 3094 } 3095 3096 static int bpf_link_release(struct inode *inode, struct file *filp) 3097 { 3098 struct bpf_link *link = filp->private_data; 3099 3100 bpf_link_put_direct(link); 3101 return 0; 3102 } 3103 3104 #ifdef CONFIG_PROC_FS 3105 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 3106 #define BPF_MAP_TYPE(_id, _ops) 3107 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 3108 static const char *bpf_link_type_strs[] = { 3109 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 3110 #include <linux/bpf_types.h> 3111 }; 3112 #undef BPF_PROG_TYPE 3113 #undef BPF_MAP_TYPE 3114 #undef BPF_LINK_TYPE 3115 3116 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 3117 { 3118 const struct bpf_link *link = filp->private_data; 3119 const struct bpf_prog *prog = link->prog; 3120 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 3121 3122 seq_printf(m, 3123 "link_type:\t%s\n" 3124 "link_id:\t%u\n", 3125 bpf_link_type_strs[link->type], 3126 link->id); 3127 if (prog) { 3128 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 3129 seq_printf(m, 3130 "prog_tag:\t%s\n" 3131 "prog_id:\t%u\n", 3132 prog_tag, 3133 prog->aux->id); 3134 } 3135 if (link->ops->show_fdinfo) 3136 link->ops->show_fdinfo(link, m); 3137 } 3138 #endif 3139 3140 static const struct file_operations bpf_link_fops = { 3141 #ifdef CONFIG_PROC_FS 3142 .show_fdinfo = bpf_link_show_fdinfo, 3143 #endif 3144 .release = bpf_link_release, 3145 .read = bpf_dummy_read, 3146 .write = bpf_dummy_write, 3147 }; 3148 3149 static int bpf_link_alloc_id(struct bpf_link *link) 3150 { 3151 int id; 3152 3153 idr_preload(GFP_KERNEL); 3154 spin_lock_bh(&link_idr_lock); 3155 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 3156 spin_unlock_bh(&link_idr_lock); 3157 idr_preload_end(); 3158 3159 return id; 3160 } 3161 3162 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 3163 * reserving unused FD and allocating ID from link_idr. This is to be paired 3164 * with bpf_link_settle() to install FD and ID and expose bpf_link to 3165 * user-space, if bpf_link is successfully attached. If not, bpf_link and 3166 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 3167 * transient state is passed around in struct bpf_link_primer. 3168 * This is preferred way to create and initialize bpf_link, especially when 3169 * there are complicated and expensive operations in between creating bpf_link 3170 * itself and attaching it to BPF hook. By using bpf_link_prime() and 3171 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 3172 * expensive (and potentially failing) roll back operations in a rare case 3173 * that file, FD, or ID can't be allocated. 3174 */ 3175 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 3176 { 3177 struct file *file; 3178 int fd, id; 3179 3180 fd = get_unused_fd_flags(O_CLOEXEC); 3181 if (fd < 0) 3182 return fd; 3183 3184 3185 id = bpf_link_alloc_id(link); 3186 if (id < 0) { 3187 put_unused_fd(fd); 3188 return id; 3189 } 3190 3191 file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC); 3192 if (IS_ERR(file)) { 3193 bpf_link_free_id(id); 3194 put_unused_fd(fd); 3195 return PTR_ERR(file); 3196 } 3197 3198 primer->link = link; 3199 primer->file = file; 3200 primer->fd = fd; 3201 primer->id = id; 3202 return 0; 3203 } 3204 3205 int bpf_link_settle(struct bpf_link_primer *primer) 3206 { 3207 /* make bpf_link fetchable by ID */ 3208 spin_lock_bh(&link_idr_lock); 3209 primer->link->id = primer->id; 3210 spin_unlock_bh(&link_idr_lock); 3211 /* make bpf_link fetchable by FD */ 3212 fd_install(primer->fd, primer->file); 3213 /* pass through installed FD */ 3214 return primer->fd; 3215 } 3216 3217 int bpf_link_new_fd(struct bpf_link *link) 3218 { 3219 return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC); 3220 } 3221 3222 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 3223 { 3224 struct fd f = fdget(ufd); 3225 struct bpf_link *link; 3226 3227 if (!f.file) 3228 return ERR_PTR(-EBADF); 3229 if (f.file->f_op != &bpf_link_fops) { 3230 fdput(f); 3231 return ERR_PTR(-EINVAL); 3232 } 3233 3234 link = f.file->private_data; 3235 bpf_link_inc(link); 3236 fdput(f); 3237 3238 return link; 3239 } 3240 EXPORT_SYMBOL(bpf_link_get_from_fd); 3241 3242 static void bpf_tracing_link_release(struct bpf_link *link) 3243 { 3244 struct bpf_tracing_link *tr_link = 3245 container_of(link, struct bpf_tracing_link, link.link); 3246 3247 WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, 3248 tr_link->trampoline)); 3249 3250 bpf_trampoline_put(tr_link->trampoline); 3251 3252 /* tgt_prog is NULL if target is a kernel function */ 3253 if (tr_link->tgt_prog) 3254 bpf_prog_put(tr_link->tgt_prog); 3255 } 3256 3257 static void bpf_tracing_link_dealloc(struct bpf_link *link) 3258 { 3259 struct bpf_tracing_link *tr_link = 3260 container_of(link, struct bpf_tracing_link, link.link); 3261 3262 kfree(tr_link); 3263 } 3264 3265 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 3266 struct seq_file *seq) 3267 { 3268 struct bpf_tracing_link *tr_link = 3269 container_of(link, struct bpf_tracing_link, link.link); 3270 u32 target_btf_id, target_obj_id; 3271 3272 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3273 &target_obj_id, &target_btf_id); 3274 seq_printf(seq, 3275 "attach_type:\t%d\n" 3276 "target_obj_id:\t%u\n" 3277 "target_btf_id:\t%u\n", 3278 tr_link->attach_type, 3279 target_obj_id, 3280 target_btf_id); 3281 } 3282 3283 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 3284 struct bpf_link_info *info) 3285 { 3286 struct bpf_tracing_link *tr_link = 3287 container_of(link, struct bpf_tracing_link, link.link); 3288 3289 info->tracing.attach_type = tr_link->attach_type; 3290 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3291 &info->tracing.target_obj_id, 3292 &info->tracing.target_btf_id); 3293 3294 return 0; 3295 } 3296 3297 static const struct bpf_link_ops bpf_tracing_link_lops = { 3298 .release = bpf_tracing_link_release, 3299 .dealloc = bpf_tracing_link_dealloc, 3300 .show_fdinfo = bpf_tracing_link_show_fdinfo, 3301 .fill_link_info = bpf_tracing_link_fill_link_info, 3302 }; 3303 3304 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 3305 int tgt_prog_fd, 3306 u32 btf_id, 3307 u64 bpf_cookie) 3308 { 3309 struct bpf_link_primer link_primer; 3310 struct bpf_prog *tgt_prog = NULL; 3311 struct bpf_trampoline *tr = NULL; 3312 struct bpf_tracing_link *link; 3313 u64 key = 0; 3314 int err; 3315 3316 switch (prog->type) { 3317 case BPF_PROG_TYPE_TRACING: 3318 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 3319 prog->expected_attach_type != BPF_TRACE_FEXIT && 3320 prog->expected_attach_type != BPF_MODIFY_RETURN) { 3321 err = -EINVAL; 3322 goto out_put_prog; 3323 } 3324 break; 3325 case BPF_PROG_TYPE_EXT: 3326 if (prog->expected_attach_type != 0) { 3327 err = -EINVAL; 3328 goto out_put_prog; 3329 } 3330 break; 3331 case BPF_PROG_TYPE_LSM: 3332 if (prog->expected_attach_type != BPF_LSM_MAC) { 3333 err = -EINVAL; 3334 goto out_put_prog; 3335 } 3336 break; 3337 default: 3338 err = -EINVAL; 3339 goto out_put_prog; 3340 } 3341 3342 if (!!tgt_prog_fd != !!btf_id) { 3343 err = -EINVAL; 3344 goto out_put_prog; 3345 } 3346 3347 if (tgt_prog_fd) { 3348 /* 3349 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this 3350 * part would be changed to implement the same for 3351 * BPF_PROG_TYPE_TRACING, do not forget to update the way how 3352 * attach_tracing_prog flag is set. 3353 */ 3354 if (prog->type != BPF_PROG_TYPE_EXT) { 3355 err = -EINVAL; 3356 goto out_put_prog; 3357 } 3358 3359 tgt_prog = bpf_prog_get(tgt_prog_fd); 3360 if (IS_ERR(tgt_prog)) { 3361 err = PTR_ERR(tgt_prog); 3362 tgt_prog = NULL; 3363 goto out_put_prog; 3364 } 3365 3366 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 3367 } 3368 3369 link = kzalloc(sizeof(*link), GFP_USER); 3370 if (!link) { 3371 err = -ENOMEM; 3372 goto out_put_prog; 3373 } 3374 bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, 3375 &bpf_tracing_link_lops, prog); 3376 link->attach_type = prog->expected_attach_type; 3377 link->link.cookie = bpf_cookie; 3378 3379 mutex_lock(&prog->aux->dst_mutex); 3380 3381 /* There are a few possible cases here: 3382 * 3383 * - if prog->aux->dst_trampoline is set, the program was just loaded 3384 * and not yet attached to anything, so we can use the values stored 3385 * in prog->aux 3386 * 3387 * - if prog->aux->dst_trampoline is NULL, the program has already been 3388 * attached to a target and its initial target was cleared (below) 3389 * 3390 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 3391 * target_btf_id using the link_create API. 3392 * 3393 * - if tgt_prog == NULL when this function was called using the old 3394 * raw_tracepoint_open API, and we need a target from prog->aux 3395 * 3396 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 3397 * was detached and is going for re-attachment. 3398 * 3399 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf 3400 * are NULL, then program was already attached and user did not provide 3401 * tgt_prog_fd so we have no way to find out or create trampoline 3402 */ 3403 if (!prog->aux->dst_trampoline && !tgt_prog) { 3404 /* 3405 * Allow re-attach for TRACING and LSM programs. If it's 3406 * currently linked, bpf_trampoline_link_prog will fail. 3407 * EXT programs need to specify tgt_prog_fd, so they 3408 * re-attach in separate code path. 3409 */ 3410 if (prog->type != BPF_PROG_TYPE_TRACING && 3411 prog->type != BPF_PROG_TYPE_LSM) { 3412 err = -EINVAL; 3413 goto out_unlock; 3414 } 3415 /* We can allow re-attach only if we have valid attach_btf. */ 3416 if (!prog->aux->attach_btf) { 3417 err = -EINVAL; 3418 goto out_unlock; 3419 } 3420 btf_id = prog->aux->attach_btf_id; 3421 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 3422 } 3423 3424 if (!prog->aux->dst_trampoline || 3425 (key && key != prog->aux->dst_trampoline->key)) { 3426 /* If there is no saved target, or the specified target is 3427 * different from the destination specified at load time, we 3428 * need a new trampoline and a check for compatibility 3429 */ 3430 struct bpf_attach_target_info tgt_info = {}; 3431 3432 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 3433 &tgt_info); 3434 if (err) 3435 goto out_unlock; 3436 3437 if (tgt_info.tgt_mod) { 3438 module_put(prog->aux->mod); 3439 prog->aux->mod = tgt_info.tgt_mod; 3440 } 3441 3442 tr = bpf_trampoline_get(key, &tgt_info); 3443 if (!tr) { 3444 err = -ENOMEM; 3445 goto out_unlock; 3446 } 3447 } else { 3448 /* The caller didn't specify a target, or the target was the 3449 * same as the destination supplied during program load. This 3450 * means we can reuse the trampoline and reference from program 3451 * load time, and there is no need to allocate a new one. This 3452 * can only happen once for any program, as the saved values in 3453 * prog->aux are cleared below. 3454 */ 3455 tr = prog->aux->dst_trampoline; 3456 tgt_prog = prog->aux->dst_prog; 3457 } 3458 3459 err = bpf_link_prime(&link->link.link, &link_primer); 3460 if (err) 3461 goto out_unlock; 3462 3463 err = bpf_trampoline_link_prog(&link->link, tr); 3464 if (err) { 3465 bpf_link_cleanup(&link_primer); 3466 link = NULL; 3467 goto out_unlock; 3468 } 3469 3470 link->tgt_prog = tgt_prog; 3471 link->trampoline = tr; 3472 3473 /* Always clear the trampoline and target prog from prog->aux to make 3474 * sure the original attach destination is not kept alive after a 3475 * program is (re-)attached to another target. 3476 */ 3477 if (prog->aux->dst_prog && 3478 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 3479 /* got extra prog ref from syscall, or attaching to different prog */ 3480 bpf_prog_put(prog->aux->dst_prog); 3481 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 3482 /* we allocated a new trampoline, so free the old one */ 3483 bpf_trampoline_put(prog->aux->dst_trampoline); 3484 3485 prog->aux->dst_prog = NULL; 3486 prog->aux->dst_trampoline = NULL; 3487 mutex_unlock(&prog->aux->dst_mutex); 3488 3489 return bpf_link_settle(&link_primer); 3490 out_unlock: 3491 if (tr && tr != prog->aux->dst_trampoline) 3492 bpf_trampoline_put(tr); 3493 mutex_unlock(&prog->aux->dst_mutex); 3494 kfree(link); 3495 out_put_prog: 3496 if (tgt_prog_fd && tgt_prog) 3497 bpf_prog_put(tgt_prog); 3498 return err; 3499 } 3500 3501 struct bpf_raw_tp_link { 3502 struct bpf_link link; 3503 struct bpf_raw_event_map *btp; 3504 }; 3505 3506 static void bpf_raw_tp_link_release(struct bpf_link *link) 3507 { 3508 struct bpf_raw_tp_link *raw_tp = 3509 container_of(link, struct bpf_raw_tp_link, link); 3510 3511 bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog); 3512 bpf_put_raw_tracepoint(raw_tp->btp); 3513 } 3514 3515 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 3516 { 3517 struct bpf_raw_tp_link *raw_tp = 3518 container_of(link, struct bpf_raw_tp_link, link); 3519 3520 kfree(raw_tp); 3521 } 3522 3523 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 3524 struct seq_file *seq) 3525 { 3526 struct bpf_raw_tp_link *raw_tp_link = 3527 container_of(link, struct bpf_raw_tp_link, link); 3528 3529 seq_printf(seq, 3530 "tp_name:\t%s\n", 3531 raw_tp_link->btp->tp->name); 3532 } 3533 3534 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, 3535 u32 len) 3536 { 3537 if (ulen >= len + 1) { 3538 if (copy_to_user(ubuf, buf, len + 1)) 3539 return -EFAULT; 3540 } else { 3541 char zero = '\0'; 3542 3543 if (copy_to_user(ubuf, buf, ulen - 1)) 3544 return -EFAULT; 3545 if (put_user(zero, ubuf + ulen - 1)) 3546 return -EFAULT; 3547 return -ENOSPC; 3548 } 3549 3550 return 0; 3551 } 3552 3553 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 3554 struct bpf_link_info *info) 3555 { 3556 struct bpf_raw_tp_link *raw_tp_link = 3557 container_of(link, struct bpf_raw_tp_link, link); 3558 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 3559 const char *tp_name = raw_tp_link->btp->tp->name; 3560 u32 ulen = info->raw_tracepoint.tp_name_len; 3561 size_t tp_len = strlen(tp_name); 3562 3563 if (!ulen ^ !ubuf) 3564 return -EINVAL; 3565 3566 info->raw_tracepoint.tp_name_len = tp_len + 1; 3567 3568 if (!ubuf) 3569 return 0; 3570 3571 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); 3572 } 3573 3574 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 3575 .release = bpf_raw_tp_link_release, 3576 .dealloc_deferred = bpf_raw_tp_link_dealloc, 3577 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 3578 .fill_link_info = bpf_raw_tp_link_fill_link_info, 3579 }; 3580 3581 #ifdef CONFIG_PERF_EVENTS 3582 struct bpf_perf_link { 3583 struct bpf_link link; 3584 struct file *perf_file; 3585 }; 3586 3587 static void bpf_perf_link_release(struct bpf_link *link) 3588 { 3589 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3590 struct perf_event *event = perf_link->perf_file->private_data; 3591 3592 perf_event_free_bpf_prog(event); 3593 fput(perf_link->perf_file); 3594 } 3595 3596 static void bpf_perf_link_dealloc(struct bpf_link *link) 3597 { 3598 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3599 3600 kfree(perf_link); 3601 } 3602 3603 static int bpf_perf_link_fill_common(const struct perf_event *event, 3604 char __user *uname, u32 ulen, 3605 u64 *probe_offset, u64 *probe_addr, 3606 u32 *fd_type, unsigned long *missed) 3607 { 3608 const char *buf; 3609 u32 prog_id; 3610 size_t len; 3611 int err; 3612 3613 if (!ulen ^ !uname) 3614 return -EINVAL; 3615 3616 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, 3617 probe_offset, probe_addr, missed); 3618 if (err) 3619 return err; 3620 if (!uname) 3621 return 0; 3622 if (buf) { 3623 len = strlen(buf); 3624 err = bpf_copy_to_user(uname, buf, ulen, len); 3625 if (err) 3626 return err; 3627 } else { 3628 char zero = '\0'; 3629 3630 if (put_user(zero, uname)) 3631 return -EFAULT; 3632 } 3633 return 0; 3634 } 3635 3636 #ifdef CONFIG_KPROBE_EVENTS 3637 static int bpf_perf_link_fill_kprobe(const struct perf_event *event, 3638 struct bpf_link_info *info) 3639 { 3640 unsigned long missed; 3641 char __user *uname; 3642 u64 addr, offset; 3643 u32 ulen, type; 3644 int err; 3645 3646 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); 3647 ulen = info->perf_event.kprobe.name_len; 3648 err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, 3649 &type, &missed); 3650 if (err) 3651 return err; 3652 if (type == BPF_FD_TYPE_KRETPROBE) 3653 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; 3654 else 3655 info->perf_event.type = BPF_PERF_EVENT_KPROBE; 3656 3657 info->perf_event.kprobe.offset = offset; 3658 info->perf_event.kprobe.missed = missed; 3659 if (!kallsyms_show_value(current_cred())) 3660 addr = 0; 3661 info->perf_event.kprobe.addr = addr; 3662 info->perf_event.kprobe.cookie = event->bpf_cookie; 3663 return 0; 3664 } 3665 #endif 3666 3667 #ifdef CONFIG_UPROBE_EVENTS 3668 static int bpf_perf_link_fill_uprobe(const struct perf_event *event, 3669 struct bpf_link_info *info) 3670 { 3671 char __user *uname; 3672 u64 addr, offset; 3673 u32 ulen, type; 3674 int err; 3675 3676 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); 3677 ulen = info->perf_event.uprobe.name_len; 3678 err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, 3679 &type, NULL); 3680 if (err) 3681 return err; 3682 3683 if (type == BPF_FD_TYPE_URETPROBE) 3684 info->perf_event.type = BPF_PERF_EVENT_URETPROBE; 3685 else 3686 info->perf_event.type = BPF_PERF_EVENT_UPROBE; 3687 info->perf_event.uprobe.offset = offset; 3688 info->perf_event.uprobe.cookie = event->bpf_cookie; 3689 return 0; 3690 } 3691 #endif 3692 3693 static int bpf_perf_link_fill_probe(const struct perf_event *event, 3694 struct bpf_link_info *info) 3695 { 3696 #ifdef CONFIG_KPROBE_EVENTS 3697 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 3698 return bpf_perf_link_fill_kprobe(event, info); 3699 #endif 3700 #ifdef CONFIG_UPROBE_EVENTS 3701 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 3702 return bpf_perf_link_fill_uprobe(event, info); 3703 #endif 3704 return -EOPNOTSUPP; 3705 } 3706 3707 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, 3708 struct bpf_link_info *info) 3709 { 3710 char __user *uname; 3711 u32 ulen; 3712 3713 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); 3714 ulen = info->perf_event.tracepoint.name_len; 3715 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; 3716 info->perf_event.tracepoint.cookie = event->bpf_cookie; 3717 return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL, NULL); 3718 } 3719 3720 static int bpf_perf_link_fill_perf_event(const struct perf_event *event, 3721 struct bpf_link_info *info) 3722 { 3723 info->perf_event.event.type = event->attr.type; 3724 info->perf_event.event.config = event->attr.config; 3725 info->perf_event.event.cookie = event->bpf_cookie; 3726 info->perf_event.type = BPF_PERF_EVENT_EVENT; 3727 return 0; 3728 } 3729 3730 static int bpf_perf_link_fill_link_info(const struct bpf_link *link, 3731 struct bpf_link_info *info) 3732 { 3733 struct bpf_perf_link *perf_link; 3734 const struct perf_event *event; 3735 3736 perf_link = container_of(link, struct bpf_perf_link, link); 3737 event = perf_get_event(perf_link->perf_file); 3738 if (IS_ERR(event)) 3739 return PTR_ERR(event); 3740 3741 switch (event->prog->type) { 3742 case BPF_PROG_TYPE_PERF_EVENT: 3743 return bpf_perf_link_fill_perf_event(event, info); 3744 case BPF_PROG_TYPE_TRACEPOINT: 3745 return bpf_perf_link_fill_tracepoint(event, info); 3746 case BPF_PROG_TYPE_KPROBE: 3747 return bpf_perf_link_fill_probe(event, info); 3748 default: 3749 return -EOPNOTSUPP; 3750 } 3751 } 3752 3753 static const struct bpf_link_ops bpf_perf_link_lops = { 3754 .release = bpf_perf_link_release, 3755 .dealloc = bpf_perf_link_dealloc, 3756 .fill_link_info = bpf_perf_link_fill_link_info, 3757 }; 3758 3759 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 3760 { 3761 struct bpf_link_primer link_primer; 3762 struct bpf_perf_link *link; 3763 struct perf_event *event; 3764 struct file *perf_file; 3765 int err; 3766 3767 if (attr->link_create.flags) 3768 return -EINVAL; 3769 3770 perf_file = perf_event_get(attr->link_create.target_fd); 3771 if (IS_ERR(perf_file)) 3772 return PTR_ERR(perf_file); 3773 3774 link = kzalloc(sizeof(*link), GFP_USER); 3775 if (!link) { 3776 err = -ENOMEM; 3777 goto out_put_file; 3778 } 3779 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); 3780 link->perf_file = perf_file; 3781 3782 err = bpf_link_prime(&link->link, &link_primer); 3783 if (err) { 3784 kfree(link); 3785 goto out_put_file; 3786 } 3787 3788 event = perf_file->private_data; 3789 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 3790 if (err) { 3791 bpf_link_cleanup(&link_primer); 3792 goto out_put_file; 3793 } 3794 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 3795 bpf_prog_inc(prog); 3796 3797 return bpf_link_settle(&link_primer); 3798 3799 out_put_file: 3800 fput(perf_file); 3801 return err; 3802 } 3803 #else 3804 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 3805 { 3806 return -EOPNOTSUPP; 3807 } 3808 #endif /* CONFIG_PERF_EVENTS */ 3809 3810 static int bpf_raw_tp_link_attach(struct bpf_prog *prog, 3811 const char __user *user_tp_name) 3812 { 3813 struct bpf_link_primer link_primer; 3814 struct bpf_raw_tp_link *link; 3815 struct bpf_raw_event_map *btp; 3816 const char *tp_name; 3817 char buf[128]; 3818 int err; 3819 3820 switch (prog->type) { 3821 case BPF_PROG_TYPE_TRACING: 3822 case BPF_PROG_TYPE_EXT: 3823 case BPF_PROG_TYPE_LSM: 3824 if (user_tp_name) 3825 /* The attach point for this category of programs 3826 * should be specified via btf_id during program load. 3827 */ 3828 return -EINVAL; 3829 if (prog->type == BPF_PROG_TYPE_TRACING && 3830 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 3831 tp_name = prog->aux->attach_func_name; 3832 break; 3833 } 3834 return bpf_tracing_prog_attach(prog, 0, 0, 0); 3835 case BPF_PROG_TYPE_RAW_TRACEPOINT: 3836 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 3837 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) 3838 return -EFAULT; 3839 buf[sizeof(buf) - 1] = 0; 3840 tp_name = buf; 3841 break; 3842 default: 3843 return -EINVAL; 3844 } 3845 3846 btp = bpf_get_raw_tracepoint(tp_name); 3847 if (!btp) 3848 return -ENOENT; 3849 3850 link = kzalloc(sizeof(*link), GFP_USER); 3851 if (!link) { 3852 err = -ENOMEM; 3853 goto out_put_btp; 3854 } 3855 bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 3856 &bpf_raw_tp_link_lops, prog); 3857 link->btp = btp; 3858 3859 err = bpf_link_prime(&link->link, &link_primer); 3860 if (err) { 3861 kfree(link); 3862 goto out_put_btp; 3863 } 3864 3865 err = bpf_probe_register(link->btp, prog); 3866 if (err) { 3867 bpf_link_cleanup(&link_primer); 3868 goto out_put_btp; 3869 } 3870 3871 return bpf_link_settle(&link_primer); 3872 3873 out_put_btp: 3874 bpf_put_raw_tracepoint(btp); 3875 return err; 3876 } 3877 3878 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd 3879 3880 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 3881 { 3882 struct bpf_prog *prog; 3883 int fd; 3884 3885 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 3886 return -EINVAL; 3887 3888 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 3889 if (IS_ERR(prog)) 3890 return PTR_ERR(prog); 3891 3892 fd = bpf_raw_tp_link_attach(prog, u64_to_user_ptr(attr->raw_tracepoint.name)); 3893 if (fd < 0) 3894 bpf_prog_put(prog); 3895 return fd; 3896 } 3897 3898 static enum bpf_prog_type 3899 attach_type_to_prog_type(enum bpf_attach_type attach_type) 3900 { 3901 switch (attach_type) { 3902 case BPF_CGROUP_INET_INGRESS: 3903 case BPF_CGROUP_INET_EGRESS: 3904 return BPF_PROG_TYPE_CGROUP_SKB; 3905 case BPF_CGROUP_INET_SOCK_CREATE: 3906 case BPF_CGROUP_INET_SOCK_RELEASE: 3907 case BPF_CGROUP_INET4_POST_BIND: 3908 case BPF_CGROUP_INET6_POST_BIND: 3909 return BPF_PROG_TYPE_CGROUP_SOCK; 3910 case BPF_CGROUP_INET4_BIND: 3911 case BPF_CGROUP_INET6_BIND: 3912 case BPF_CGROUP_INET4_CONNECT: 3913 case BPF_CGROUP_INET6_CONNECT: 3914 case BPF_CGROUP_UNIX_CONNECT: 3915 case BPF_CGROUP_INET4_GETPEERNAME: 3916 case BPF_CGROUP_INET6_GETPEERNAME: 3917 case BPF_CGROUP_UNIX_GETPEERNAME: 3918 case BPF_CGROUP_INET4_GETSOCKNAME: 3919 case BPF_CGROUP_INET6_GETSOCKNAME: 3920 case BPF_CGROUP_UNIX_GETSOCKNAME: 3921 case BPF_CGROUP_UDP4_SENDMSG: 3922 case BPF_CGROUP_UDP6_SENDMSG: 3923 case BPF_CGROUP_UNIX_SENDMSG: 3924 case BPF_CGROUP_UDP4_RECVMSG: 3925 case BPF_CGROUP_UDP6_RECVMSG: 3926 case BPF_CGROUP_UNIX_RECVMSG: 3927 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 3928 case BPF_CGROUP_SOCK_OPS: 3929 return BPF_PROG_TYPE_SOCK_OPS; 3930 case BPF_CGROUP_DEVICE: 3931 return BPF_PROG_TYPE_CGROUP_DEVICE; 3932 case BPF_SK_MSG_VERDICT: 3933 return BPF_PROG_TYPE_SK_MSG; 3934 case BPF_SK_SKB_STREAM_PARSER: 3935 case BPF_SK_SKB_STREAM_VERDICT: 3936 case BPF_SK_SKB_VERDICT: 3937 return BPF_PROG_TYPE_SK_SKB; 3938 case BPF_LIRC_MODE2: 3939 return BPF_PROG_TYPE_LIRC_MODE2; 3940 case BPF_FLOW_DISSECTOR: 3941 return BPF_PROG_TYPE_FLOW_DISSECTOR; 3942 case BPF_CGROUP_SYSCTL: 3943 return BPF_PROG_TYPE_CGROUP_SYSCTL; 3944 case BPF_CGROUP_GETSOCKOPT: 3945 case BPF_CGROUP_SETSOCKOPT: 3946 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 3947 case BPF_TRACE_ITER: 3948 case BPF_TRACE_RAW_TP: 3949 case BPF_TRACE_FENTRY: 3950 case BPF_TRACE_FEXIT: 3951 case BPF_MODIFY_RETURN: 3952 return BPF_PROG_TYPE_TRACING; 3953 case BPF_LSM_MAC: 3954 return BPF_PROG_TYPE_LSM; 3955 case BPF_SK_LOOKUP: 3956 return BPF_PROG_TYPE_SK_LOOKUP; 3957 case BPF_XDP: 3958 return BPF_PROG_TYPE_XDP; 3959 case BPF_LSM_CGROUP: 3960 return BPF_PROG_TYPE_LSM; 3961 case BPF_TCX_INGRESS: 3962 case BPF_TCX_EGRESS: 3963 case BPF_NETKIT_PRIMARY: 3964 case BPF_NETKIT_PEER: 3965 return BPF_PROG_TYPE_SCHED_CLS; 3966 default: 3967 return BPF_PROG_TYPE_UNSPEC; 3968 } 3969 } 3970 3971 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 3972 enum bpf_attach_type attach_type) 3973 { 3974 enum bpf_prog_type ptype; 3975 3976 switch (prog->type) { 3977 case BPF_PROG_TYPE_CGROUP_SOCK: 3978 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 3979 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 3980 case BPF_PROG_TYPE_SK_LOOKUP: 3981 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 3982 case BPF_PROG_TYPE_CGROUP_SKB: 3983 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) 3984 /* cg-skb progs can be loaded by unpriv user. 3985 * check permissions at attach time. 3986 */ 3987 return -EPERM; 3988 return prog->enforce_expected_attach_type && 3989 prog->expected_attach_type != attach_type ? 3990 -EINVAL : 0; 3991 case BPF_PROG_TYPE_EXT: 3992 return 0; 3993 case BPF_PROG_TYPE_NETFILTER: 3994 if (attach_type != BPF_NETFILTER) 3995 return -EINVAL; 3996 return 0; 3997 case BPF_PROG_TYPE_PERF_EVENT: 3998 case BPF_PROG_TYPE_TRACEPOINT: 3999 if (attach_type != BPF_PERF_EVENT) 4000 return -EINVAL; 4001 return 0; 4002 case BPF_PROG_TYPE_KPROBE: 4003 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && 4004 attach_type != BPF_TRACE_KPROBE_MULTI) 4005 return -EINVAL; 4006 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && 4007 attach_type != BPF_TRACE_UPROBE_MULTI) 4008 return -EINVAL; 4009 if (attach_type != BPF_PERF_EVENT && 4010 attach_type != BPF_TRACE_KPROBE_MULTI && 4011 attach_type != BPF_TRACE_UPROBE_MULTI) 4012 return -EINVAL; 4013 return 0; 4014 case BPF_PROG_TYPE_SCHED_CLS: 4015 if (attach_type != BPF_TCX_INGRESS && 4016 attach_type != BPF_TCX_EGRESS && 4017 attach_type != BPF_NETKIT_PRIMARY && 4018 attach_type != BPF_NETKIT_PEER) 4019 return -EINVAL; 4020 return 0; 4021 default: 4022 ptype = attach_type_to_prog_type(attach_type); 4023 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) 4024 return -EINVAL; 4025 return 0; 4026 } 4027 } 4028 4029 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision 4030 4031 #define BPF_F_ATTACH_MASK_BASE \ 4032 (BPF_F_ALLOW_OVERRIDE | \ 4033 BPF_F_ALLOW_MULTI | \ 4034 BPF_F_REPLACE) 4035 4036 #define BPF_F_ATTACH_MASK_MPROG \ 4037 (BPF_F_REPLACE | \ 4038 BPF_F_BEFORE | \ 4039 BPF_F_AFTER | \ 4040 BPF_F_ID | \ 4041 BPF_F_LINK) 4042 4043 static int bpf_prog_attach(const union bpf_attr *attr) 4044 { 4045 enum bpf_prog_type ptype; 4046 struct bpf_prog *prog; 4047 int ret; 4048 4049 if (CHECK_ATTR(BPF_PROG_ATTACH)) 4050 return -EINVAL; 4051 4052 ptype = attach_type_to_prog_type(attr->attach_type); 4053 if (ptype == BPF_PROG_TYPE_UNSPEC) 4054 return -EINVAL; 4055 if (bpf_mprog_supported(ptype)) { 4056 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4057 return -EINVAL; 4058 } else { 4059 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) 4060 return -EINVAL; 4061 if (attr->relative_fd || 4062 attr->expected_revision) 4063 return -EINVAL; 4064 } 4065 4066 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4067 if (IS_ERR(prog)) 4068 return PTR_ERR(prog); 4069 4070 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 4071 bpf_prog_put(prog); 4072 return -EINVAL; 4073 } 4074 4075 switch (ptype) { 4076 case BPF_PROG_TYPE_SK_SKB: 4077 case BPF_PROG_TYPE_SK_MSG: 4078 ret = sock_map_get_from_fd(attr, prog); 4079 break; 4080 case BPF_PROG_TYPE_LIRC_MODE2: 4081 ret = lirc_prog_attach(attr, prog); 4082 break; 4083 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4084 ret = netns_bpf_prog_attach(attr, prog); 4085 break; 4086 case BPF_PROG_TYPE_CGROUP_DEVICE: 4087 case BPF_PROG_TYPE_CGROUP_SKB: 4088 case BPF_PROG_TYPE_CGROUP_SOCK: 4089 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4090 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4091 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4092 case BPF_PROG_TYPE_SOCK_OPS: 4093 case BPF_PROG_TYPE_LSM: 4094 if (ptype == BPF_PROG_TYPE_LSM && 4095 prog->expected_attach_type != BPF_LSM_CGROUP) 4096 ret = -EINVAL; 4097 else 4098 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 4099 break; 4100 case BPF_PROG_TYPE_SCHED_CLS: 4101 if (attr->attach_type == BPF_TCX_INGRESS || 4102 attr->attach_type == BPF_TCX_EGRESS) 4103 ret = tcx_prog_attach(attr, prog); 4104 else 4105 ret = netkit_prog_attach(attr, prog); 4106 break; 4107 default: 4108 ret = -EINVAL; 4109 } 4110 4111 if (ret) 4112 bpf_prog_put(prog); 4113 return ret; 4114 } 4115 4116 #define BPF_PROG_DETACH_LAST_FIELD expected_revision 4117 4118 static int bpf_prog_detach(const union bpf_attr *attr) 4119 { 4120 struct bpf_prog *prog = NULL; 4121 enum bpf_prog_type ptype; 4122 int ret; 4123 4124 if (CHECK_ATTR(BPF_PROG_DETACH)) 4125 return -EINVAL; 4126 4127 ptype = attach_type_to_prog_type(attr->attach_type); 4128 if (bpf_mprog_supported(ptype)) { 4129 if (ptype == BPF_PROG_TYPE_UNSPEC) 4130 return -EINVAL; 4131 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4132 return -EINVAL; 4133 if (attr->attach_bpf_fd) { 4134 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4135 if (IS_ERR(prog)) 4136 return PTR_ERR(prog); 4137 } 4138 } else if (attr->attach_flags || 4139 attr->relative_fd || 4140 attr->expected_revision) { 4141 return -EINVAL; 4142 } 4143 4144 switch (ptype) { 4145 case BPF_PROG_TYPE_SK_MSG: 4146 case BPF_PROG_TYPE_SK_SKB: 4147 ret = sock_map_prog_detach(attr, ptype); 4148 break; 4149 case BPF_PROG_TYPE_LIRC_MODE2: 4150 ret = lirc_prog_detach(attr); 4151 break; 4152 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4153 ret = netns_bpf_prog_detach(attr, ptype); 4154 break; 4155 case BPF_PROG_TYPE_CGROUP_DEVICE: 4156 case BPF_PROG_TYPE_CGROUP_SKB: 4157 case BPF_PROG_TYPE_CGROUP_SOCK: 4158 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4159 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4160 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4161 case BPF_PROG_TYPE_SOCK_OPS: 4162 case BPF_PROG_TYPE_LSM: 4163 ret = cgroup_bpf_prog_detach(attr, ptype); 4164 break; 4165 case BPF_PROG_TYPE_SCHED_CLS: 4166 if (attr->attach_type == BPF_TCX_INGRESS || 4167 attr->attach_type == BPF_TCX_EGRESS) 4168 ret = tcx_prog_detach(attr, prog); 4169 else 4170 ret = netkit_prog_detach(attr, prog); 4171 break; 4172 default: 4173 ret = -EINVAL; 4174 } 4175 4176 if (prog) 4177 bpf_prog_put(prog); 4178 return ret; 4179 } 4180 4181 #define BPF_PROG_QUERY_LAST_FIELD query.revision 4182 4183 static int bpf_prog_query(const union bpf_attr *attr, 4184 union bpf_attr __user *uattr) 4185 { 4186 if (!bpf_net_capable()) 4187 return -EPERM; 4188 if (CHECK_ATTR(BPF_PROG_QUERY)) 4189 return -EINVAL; 4190 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 4191 return -EINVAL; 4192 4193 switch (attr->query.attach_type) { 4194 case BPF_CGROUP_INET_INGRESS: 4195 case BPF_CGROUP_INET_EGRESS: 4196 case BPF_CGROUP_INET_SOCK_CREATE: 4197 case BPF_CGROUP_INET_SOCK_RELEASE: 4198 case BPF_CGROUP_INET4_BIND: 4199 case BPF_CGROUP_INET6_BIND: 4200 case BPF_CGROUP_INET4_POST_BIND: 4201 case BPF_CGROUP_INET6_POST_BIND: 4202 case BPF_CGROUP_INET4_CONNECT: 4203 case BPF_CGROUP_INET6_CONNECT: 4204 case BPF_CGROUP_UNIX_CONNECT: 4205 case BPF_CGROUP_INET4_GETPEERNAME: 4206 case BPF_CGROUP_INET6_GETPEERNAME: 4207 case BPF_CGROUP_UNIX_GETPEERNAME: 4208 case BPF_CGROUP_INET4_GETSOCKNAME: 4209 case BPF_CGROUP_INET6_GETSOCKNAME: 4210 case BPF_CGROUP_UNIX_GETSOCKNAME: 4211 case BPF_CGROUP_UDP4_SENDMSG: 4212 case BPF_CGROUP_UDP6_SENDMSG: 4213 case BPF_CGROUP_UNIX_SENDMSG: 4214 case BPF_CGROUP_UDP4_RECVMSG: 4215 case BPF_CGROUP_UDP6_RECVMSG: 4216 case BPF_CGROUP_UNIX_RECVMSG: 4217 case BPF_CGROUP_SOCK_OPS: 4218 case BPF_CGROUP_DEVICE: 4219 case BPF_CGROUP_SYSCTL: 4220 case BPF_CGROUP_GETSOCKOPT: 4221 case BPF_CGROUP_SETSOCKOPT: 4222 case BPF_LSM_CGROUP: 4223 return cgroup_bpf_prog_query(attr, uattr); 4224 case BPF_LIRC_MODE2: 4225 return lirc_prog_query(attr, uattr); 4226 case BPF_FLOW_DISSECTOR: 4227 case BPF_SK_LOOKUP: 4228 return netns_bpf_prog_query(attr, uattr); 4229 case BPF_SK_SKB_STREAM_PARSER: 4230 case BPF_SK_SKB_STREAM_VERDICT: 4231 case BPF_SK_MSG_VERDICT: 4232 case BPF_SK_SKB_VERDICT: 4233 return sock_map_bpf_prog_query(attr, uattr); 4234 case BPF_TCX_INGRESS: 4235 case BPF_TCX_EGRESS: 4236 return tcx_prog_query(attr, uattr); 4237 case BPF_NETKIT_PRIMARY: 4238 case BPF_NETKIT_PEER: 4239 return netkit_prog_query(attr, uattr); 4240 default: 4241 return -EINVAL; 4242 } 4243 } 4244 4245 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size 4246 4247 static int bpf_prog_test_run(const union bpf_attr *attr, 4248 union bpf_attr __user *uattr) 4249 { 4250 struct bpf_prog *prog; 4251 int ret = -ENOTSUPP; 4252 4253 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 4254 return -EINVAL; 4255 4256 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 4257 (!attr->test.ctx_size_in && attr->test.ctx_in)) 4258 return -EINVAL; 4259 4260 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 4261 (!attr->test.ctx_size_out && attr->test.ctx_out)) 4262 return -EINVAL; 4263 4264 prog = bpf_prog_get(attr->test.prog_fd); 4265 if (IS_ERR(prog)) 4266 return PTR_ERR(prog); 4267 4268 if (prog->aux->ops->test_run) 4269 ret = prog->aux->ops->test_run(prog, attr, uattr); 4270 4271 bpf_prog_put(prog); 4272 return ret; 4273 } 4274 4275 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 4276 4277 static int bpf_obj_get_next_id(const union bpf_attr *attr, 4278 union bpf_attr __user *uattr, 4279 struct idr *idr, 4280 spinlock_t *lock) 4281 { 4282 u32 next_id = attr->start_id; 4283 int err = 0; 4284 4285 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 4286 return -EINVAL; 4287 4288 if (!capable(CAP_SYS_ADMIN)) 4289 return -EPERM; 4290 4291 next_id++; 4292 spin_lock_bh(lock); 4293 if (!idr_get_next(idr, &next_id)) 4294 err = -ENOENT; 4295 spin_unlock_bh(lock); 4296 4297 if (!err) 4298 err = put_user(next_id, &uattr->next_id); 4299 4300 return err; 4301 } 4302 4303 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 4304 { 4305 struct bpf_map *map; 4306 4307 spin_lock_bh(&map_idr_lock); 4308 again: 4309 map = idr_get_next(&map_idr, id); 4310 if (map) { 4311 map = __bpf_map_inc_not_zero(map, false); 4312 if (IS_ERR(map)) { 4313 (*id)++; 4314 goto again; 4315 } 4316 } 4317 spin_unlock_bh(&map_idr_lock); 4318 4319 return map; 4320 } 4321 4322 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 4323 { 4324 struct bpf_prog *prog; 4325 4326 spin_lock_bh(&prog_idr_lock); 4327 again: 4328 prog = idr_get_next(&prog_idr, id); 4329 if (prog) { 4330 prog = bpf_prog_inc_not_zero(prog); 4331 if (IS_ERR(prog)) { 4332 (*id)++; 4333 goto again; 4334 } 4335 } 4336 spin_unlock_bh(&prog_idr_lock); 4337 4338 return prog; 4339 } 4340 4341 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 4342 4343 struct bpf_prog *bpf_prog_by_id(u32 id) 4344 { 4345 struct bpf_prog *prog; 4346 4347 if (!id) 4348 return ERR_PTR(-ENOENT); 4349 4350 spin_lock_bh(&prog_idr_lock); 4351 prog = idr_find(&prog_idr, id); 4352 if (prog) 4353 prog = bpf_prog_inc_not_zero(prog); 4354 else 4355 prog = ERR_PTR(-ENOENT); 4356 spin_unlock_bh(&prog_idr_lock); 4357 return prog; 4358 } 4359 4360 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 4361 { 4362 struct bpf_prog *prog; 4363 u32 id = attr->prog_id; 4364 int fd; 4365 4366 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 4367 return -EINVAL; 4368 4369 if (!capable(CAP_SYS_ADMIN)) 4370 return -EPERM; 4371 4372 prog = bpf_prog_by_id(id); 4373 if (IS_ERR(prog)) 4374 return PTR_ERR(prog); 4375 4376 fd = bpf_prog_new_fd(prog); 4377 if (fd < 0) 4378 bpf_prog_put(prog); 4379 4380 return fd; 4381 } 4382 4383 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 4384 4385 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 4386 { 4387 struct bpf_map *map; 4388 u32 id = attr->map_id; 4389 int f_flags; 4390 int fd; 4391 4392 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 4393 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 4394 return -EINVAL; 4395 4396 if (!capable(CAP_SYS_ADMIN)) 4397 return -EPERM; 4398 4399 f_flags = bpf_get_file_flag(attr->open_flags); 4400 if (f_flags < 0) 4401 return f_flags; 4402 4403 spin_lock_bh(&map_idr_lock); 4404 map = idr_find(&map_idr, id); 4405 if (map) 4406 map = __bpf_map_inc_not_zero(map, true); 4407 else 4408 map = ERR_PTR(-ENOENT); 4409 spin_unlock_bh(&map_idr_lock); 4410 4411 if (IS_ERR(map)) 4412 return PTR_ERR(map); 4413 4414 fd = bpf_map_new_fd(map, f_flags); 4415 if (fd < 0) 4416 bpf_map_put_with_uref(map); 4417 4418 return fd; 4419 } 4420 4421 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 4422 unsigned long addr, u32 *off, 4423 u32 *type) 4424 { 4425 const struct bpf_map *map; 4426 int i; 4427 4428 mutex_lock(&prog->aux->used_maps_mutex); 4429 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 4430 map = prog->aux->used_maps[i]; 4431 if (map == (void *)addr) { 4432 *type = BPF_PSEUDO_MAP_FD; 4433 goto out; 4434 } 4435 if (!map->ops->map_direct_value_meta) 4436 continue; 4437 if (!map->ops->map_direct_value_meta(map, addr, off)) { 4438 *type = BPF_PSEUDO_MAP_VALUE; 4439 goto out; 4440 } 4441 } 4442 map = NULL; 4443 4444 out: 4445 mutex_unlock(&prog->aux->used_maps_mutex); 4446 return map; 4447 } 4448 4449 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 4450 const struct cred *f_cred) 4451 { 4452 const struct bpf_map *map; 4453 struct bpf_insn *insns; 4454 u32 off, type; 4455 u64 imm; 4456 u8 code; 4457 int i; 4458 4459 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 4460 GFP_USER); 4461 if (!insns) 4462 return insns; 4463 4464 for (i = 0; i < prog->len; i++) { 4465 code = insns[i].code; 4466 4467 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 4468 insns[i].code = BPF_JMP | BPF_CALL; 4469 insns[i].imm = BPF_FUNC_tail_call; 4470 /* fall-through */ 4471 } 4472 if (code == (BPF_JMP | BPF_CALL) || 4473 code == (BPF_JMP | BPF_CALL_ARGS)) { 4474 if (code == (BPF_JMP | BPF_CALL_ARGS)) 4475 insns[i].code = BPF_JMP | BPF_CALL; 4476 if (!bpf_dump_raw_ok(f_cred)) 4477 insns[i].imm = 0; 4478 continue; 4479 } 4480 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 4481 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 4482 continue; 4483 } 4484 4485 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || 4486 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { 4487 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; 4488 continue; 4489 } 4490 4491 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 4492 continue; 4493 4494 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 4495 map = bpf_map_from_imm(prog, imm, &off, &type); 4496 if (map) { 4497 insns[i].src_reg = type; 4498 insns[i].imm = map->id; 4499 insns[i + 1].imm = off; 4500 continue; 4501 } 4502 } 4503 4504 return insns; 4505 } 4506 4507 static int set_info_rec_size(struct bpf_prog_info *info) 4508 { 4509 /* 4510 * Ensure info.*_rec_size is the same as kernel expected size 4511 * 4512 * or 4513 * 4514 * Only allow zero *_rec_size if both _rec_size and _cnt are 4515 * zero. In this case, the kernel will set the expected 4516 * _rec_size back to the info. 4517 */ 4518 4519 if ((info->nr_func_info || info->func_info_rec_size) && 4520 info->func_info_rec_size != sizeof(struct bpf_func_info)) 4521 return -EINVAL; 4522 4523 if ((info->nr_line_info || info->line_info_rec_size) && 4524 info->line_info_rec_size != sizeof(struct bpf_line_info)) 4525 return -EINVAL; 4526 4527 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 4528 info->jited_line_info_rec_size != sizeof(__u64)) 4529 return -EINVAL; 4530 4531 info->func_info_rec_size = sizeof(struct bpf_func_info); 4532 info->line_info_rec_size = sizeof(struct bpf_line_info); 4533 info->jited_line_info_rec_size = sizeof(__u64); 4534 4535 return 0; 4536 } 4537 4538 static int bpf_prog_get_info_by_fd(struct file *file, 4539 struct bpf_prog *prog, 4540 const union bpf_attr *attr, 4541 union bpf_attr __user *uattr) 4542 { 4543 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4544 struct btf *attach_btf = bpf_prog_get_target_btf(prog); 4545 struct bpf_prog_info info; 4546 u32 info_len = attr->info.info_len; 4547 struct bpf_prog_kstats stats; 4548 char __user *uinsns; 4549 u32 ulen; 4550 int err; 4551 4552 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4553 if (err) 4554 return err; 4555 info_len = min_t(u32, sizeof(info), info_len); 4556 4557 memset(&info, 0, sizeof(info)); 4558 if (copy_from_user(&info, uinfo, info_len)) 4559 return -EFAULT; 4560 4561 info.type = prog->type; 4562 info.id = prog->aux->id; 4563 info.load_time = prog->aux->load_time; 4564 info.created_by_uid = from_kuid_munged(current_user_ns(), 4565 prog->aux->user->uid); 4566 info.gpl_compatible = prog->gpl_compatible; 4567 4568 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 4569 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 4570 4571 mutex_lock(&prog->aux->used_maps_mutex); 4572 ulen = info.nr_map_ids; 4573 info.nr_map_ids = prog->aux->used_map_cnt; 4574 ulen = min_t(u32, info.nr_map_ids, ulen); 4575 if (ulen) { 4576 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 4577 u32 i; 4578 4579 for (i = 0; i < ulen; i++) 4580 if (put_user(prog->aux->used_maps[i]->id, 4581 &user_map_ids[i])) { 4582 mutex_unlock(&prog->aux->used_maps_mutex); 4583 return -EFAULT; 4584 } 4585 } 4586 mutex_unlock(&prog->aux->used_maps_mutex); 4587 4588 err = set_info_rec_size(&info); 4589 if (err) 4590 return err; 4591 4592 bpf_prog_get_stats(prog, &stats); 4593 info.run_time_ns = stats.nsecs; 4594 info.run_cnt = stats.cnt; 4595 info.recursion_misses = stats.misses; 4596 4597 info.verified_insns = prog->aux->verified_insns; 4598 4599 if (!bpf_capable()) { 4600 info.jited_prog_len = 0; 4601 info.xlated_prog_len = 0; 4602 info.nr_jited_ksyms = 0; 4603 info.nr_jited_func_lens = 0; 4604 info.nr_func_info = 0; 4605 info.nr_line_info = 0; 4606 info.nr_jited_line_info = 0; 4607 goto done; 4608 } 4609 4610 ulen = info.xlated_prog_len; 4611 info.xlated_prog_len = bpf_prog_insn_size(prog); 4612 if (info.xlated_prog_len && ulen) { 4613 struct bpf_insn *insns_sanitized; 4614 bool fault; 4615 4616 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 4617 info.xlated_prog_insns = 0; 4618 goto done; 4619 } 4620 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 4621 if (!insns_sanitized) 4622 return -ENOMEM; 4623 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 4624 ulen = min_t(u32, info.xlated_prog_len, ulen); 4625 fault = copy_to_user(uinsns, insns_sanitized, ulen); 4626 kfree(insns_sanitized); 4627 if (fault) 4628 return -EFAULT; 4629 } 4630 4631 if (bpf_prog_is_offloaded(prog->aux)) { 4632 err = bpf_prog_offload_info_fill(&info, prog); 4633 if (err) 4634 return err; 4635 goto done; 4636 } 4637 4638 /* NOTE: the following code is supposed to be skipped for offload. 4639 * bpf_prog_offload_info_fill() is the place to fill similar fields 4640 * for offload. 4641 */ 4642 ulen = info.jited_prog_len; 4643 if (prog->aux->func_cnt) { 4644 u32 i; 4645 4646 info.jited_prog_len = 0; 4647 for (i = 0; i < prog->aux->func_cnt; i++) 4648 info.jited_prog_len += prog->aux->func[i]->jited_len; 4649 } else { 4650 info.jited_prog_len = prog->jited_len; 4651 } 4652 4653 if (info.jited_prog_len && ulen) { 4654 if (bpf_dump_raw_ok(file->f_cred)) { 4655 uinsns = u64_to_user_ptr(info.jited_prog_insns); 4656 ulen = min_t(u32, info.jited_prog_len, ulen); 4657 4658 /* for multi-function programs, copy the JITed 4659 * instructions for all the functions 4660 */ 4661 if (prog->aux->func_cnt) { 4662 u32 len, free, i; 4663 u8 *img; 4664 4665 free = ulen; 4666 for (i = 0; i < prog->aux->func_cnt; i++) { 4667 len = prog->aux->func[i]->jited_len; 4668 len = min_t(u32, len, free); 4669 img = (u8 *) prog->aux->func[i]->bpf_func; 4670 if (copy_to_user(uinsns, img, len)) 4671 return -EFAULT; 4672 uinsns += len; 4673 free -= len; 4674 if (!free) 4675 break; 4676 } 4677 } else { 4678 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 4679 return -EFAULT; 4680 } 4681 } else { 4682 info.jited_prog_insns = 0; 4683 } 4684 } 4685 4686 ulen = info.nr_jited_ksyms; 4687 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 4688 if (ulen) { 4689 if (bpf_dump_raw_ok(file->f_cred)) { 4690 unsigned long ksym_addr; 4691 u64 __user *user_ksyms; 4692 u32 i; 4693 4694 /* copy the address of the kernel symbol 4695 * corresponding to each function 4696 */ 4697 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 4698 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 4699 if (prog->aux->func_cnt) { 4700 for (i = 0; i < ulen; i++) { 4701 ksym_addr = (unsigned long) 4702 prog->aux->func[i]->bpf_func; 4703 if (put_user((u64) ksym_addr, 4704 &user_ksyms[i])) 4705 return -EFAULT; 4706 } 4707 } else { 4708 ksym_addr = (unsigned long) prog->bpf_func; 4709 if (put_user((u64) ksym_addr, &user_ksyms[0])) 4710 return -EFAULT; 4711 } 4712 } else { 4713 info.jited_ksyms = 0; 4714 } 4715 } 4716 4717 ulen = info.nr_jited_func_lens; 4718 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 4719 if (ulen) { 4720 if (bpf_dump_raw_ok(file->f_cred)) { 4721 u32 __user *user_lens; 4722 u32 func_len, i; 4723 4724 /* copy the JITed image lengths for each function */ 4725 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 4726 user_lens = u64_to_user_ptr(info.jited_func_lens); 4727 if (prog->aux->func_cnt) { 4728 for (i = 0; i < ulen; i++) { 4729 func_len = 4730 prog->aux->func[i]->jited_len; 4731 if (put_user(func_len, &user_lens[i])) 4732 return -EFAULT; 4733 } 4734 } else { 4735 func_len = prog->jited_len; 4736 if (put_user(func_len, &user_lens[0])) 4737 return -EFAULT; 4738 } 4739 } else { 4740 info.jited_func_lens = 0; 4741 } 4742 } 4743 4744 if (prog->aux->btf) 4745 info.btf_id = btf_obj_id(prog->aux->btf); 4746 info.attach_btf_id = prog->aux->attach_btf_id; 4747 if (attach_btf) 4748 info.attach_btf_obj_id = btf_obj_id(attach_btf); 4749 4750 ulen = info.nr_func_info; 4751 info.nr_func_info = prog->aux->func_info_cnt; 4752 if (info.nr_func_info && ulen) { 4753 char __user *user_finfo; 4754 4755 user_finfo = u64_to_user_ptr(info.func_info); 4756 ulen = min_t(u32, info.nr_func_info, ulen); 4757 if (copy_to_user(user_finfo, prog->aux->func_info, 4758 info.func_info_rec_size * ulen)) 4759 return -EFAULT; 4760 } 4761 4762 ulen = info.nr_line_info; 4763 info.nr_line_info = prog->aux->nr_linfo; 4764 if (info.nr_line_info && ulen) { 4765 __u8 __user *user_linfo; 4766 4767 user_linfo = u64_to_user_ptr(info.line_info); 4768 ulen = min_t(u32, info.nr_line_info, ulen); 4769 if (copy_to_user(user_linfo, prog->aux->linfo, 4770 info.line_info_rec_size * ulen)) 4771 return -EFAULT; 4772 } 4773 4774 ulen = info.nr_jited_line_info; 4775 if (prog->aux->jited_linfo) 4776 info.nr_jited_line_info = prog->aux->nr_linfo; 4777 else 4778 info.nr_jited_line_info = 0; 4779 if (info.nr_jited_line_info && ulen) { 4780 if (bpf_dump_raw_ok(file->f_cred)) { 4781 unsigned long line_addr; 4782 __u64 __user *user_linfo; 4783 u32 i; 4784 4785 user_linfo = u64_to_user_ptr(info.jited_line_info); 4786 ulen = min_t(u32, info.nr_jited_line_info, ulen); 4787 for (i = 0; i < ulen; i++) { 4788 line_addr = (unsigned long)prog->aux->jited_linfo[i]; 4789 if (put_user((__u64)line_addr, &user_linfo[i])) 4790 return -EFAULT; 4791 } 4792 } else { 4793 info.jited_line_info = 0; 4794 } 4795 } 4796 4797 ulen = info.nr_prog_tags; 4798 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 4799 if (ulen) { 4800 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 4801 u32 i; 4802 4803 user_prog_tags = u64_to_user_ptr(info.prog_tags); 4804 ulen = min_t(u32, info.nr_prog_tags, ulen); 4805 if (prog->aux->func_cnt) { 4806 for (i = 0; i < ulen; i++) { 4807 if (copy_to_user(user_prog_tags[i], 4808 prog->aux->func[i]->tag, 4809 BPF_TAG_SIZE)) 4810 return -EFAULT; 4811 } 4812 } else { 4813 if (copy_to_user(user_prog_tags[0], 4814 prog->tag, BPF_TAG_SIZE)) 4815 return -EFAULT; 4816 } 4817 } 4818 4819 done: 4820 if (copy_to_user(uinfo, &info, info_len) || 4821 put_user(info_len, &uattr->info.info_len)) 4822 return -EFAULT; 4823 4824 return 0; 4825 } 4826 4827 static int bpf_map_get_info_by_fd(struct file *file, 4828 struct bpf_map *map, 4829 const union bpf_attr *attr, 4830 union bpf_attr __user *uattr) 4831 { 4832 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4833 struct bpf_map_info info; 4834 u32 info_len = attr->info.info_len; 4835 int err; 4836 4837 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4838 if (err) 4839 return err; 4840 info_len = min_t(u32, sizeof(info), info_len); 4841 4842 memset(&info, 0, sizeof(info)); 4843 info.type = map->map_type; 4844 info.id = map->id; 4845 info.key_size = map->key_size; 4846 info.value_size = map->value_size; 4847 info.max_entries = map->max_entries; 4848 info.map_flags = map->map_flags; 4849 info.map_extra = map->map_extra; 4850 memcpy(info.name, map->name, sizeof(map->name)); 4851 4852 if (map->btf) { 4853 info.btf_id = btf_obj_id(map->btf); 4854 info.btf_key_type_id = map->btf_key_type_id; 4855 info.btf_value_type_id = map->btf_value_type_id; 4856 } 4857 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 4858 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) 4859 bpf_map_struct_ops_info_fill(&info, map); 4860 4861 if (bpf_map_is_offloaded(map)) { 4862 err = bpf_map_offload_info_fill(&info, map); 4863 if (err) 4864 return err; 4865 } 4866 4867 if (copy_to_user(uinfo, &info, info_len) || 4868 put_user(info_len, &uattr->info.info_len)) 4869 return -EFAULT; 4870 4871 return 0; 4872 } 4873 4874 static int bpf_btf_get_info_by_fd(struct file *file, 4875 struct btf *btf, 4876 const union bpf_attr *attr, 4877 union bpf_attr __user *uattr) 4878 { 4879 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4880 u32 info_len = attr->info.info_len; 4881 int err; 4882 4883 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 4884 if (err) 4885 return err; 4886 4887 return btf_get_info_by_fd(btf, attr, uattr); 4888 } 4889 4890 static int bpf_link_get_info_by_fd(struct file *file, 4891 struct bpf_link *link, 4892 const union bpf_attr *attr, 4893 union bpf_attr __user *uattr) 4894 { 4895 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4896 struct bpf_link_info info; 4897 u32 info_len = attr->info.info_len; 4898 int err; 4899 4900 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4901 if (err) 4902 return err; 4903 info_len = min_t(u32, sizeof(info), info_len); 4904 4905 memset(&info, 0, sizeof(info)); 4906 if (copy_from_user(&info, uinfo, info_len)) 4907 return -EFAULT; 4908 4909 info.type = link->type; 4910 info.id = link->id; 4911 if (link->prog) 4912 info.prog_id = link->prog->aux->id; 4913 4914 if (link->ops->fill_link_info) { 4915 err = link->ops->fill_link_info(link, &info); 4916 if (err) 4917 return err; 4918 } 4919 4920 if (copy_to_user(uinfo, &info, info_len) || 4921 put_user(info_len, &uattr->info.info_len)) 4922 return -EFAULT; 4923 4924 return 0; 4925 } 4926 4927 4928 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 4929 4930 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 4931 union bpf_attr __user *uattr) 4932 { 4933 int ufd = attr->info.bpf_fd; 4934 struct fd f; 4935 int err; 4936 4937 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 4938 return -EINVAL; 4939 4940 f = fdget(ufd); 4941 if (!f.file) 4942 return -EBADFD; 4943 4944 if (f.file->f_op == &bpf_prog_fops) 4945 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr, 4946 uattr); 4947 else if (f.file->f_op == &bpf_map_fops) 4948 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr, 4949 uattr); 4950 else if (f.file->f_op == &btf_fops) 4951 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr); 4952 else if (f.file->f_op == &bpf_link_fops) 4953 err = bpf_link_get_info_by_fd(f.file, f.file->private_data, 4954 attr, uattr); 4955 else 4956 err = -EINVAL; 4957 4958 fdput(f); 4959 return err; 4960 } 4961 4962 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd 4963 4964 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) 4965 { 4966 struct bpf_token *token = NULL; 4967 4968 if (CHECK_ATTR(BPF_BTF_LOAD)) 4969 return -EINVAL; 4970 4971 if (attr->btf_flags & ~BPF_F_TOKEN_FD) 4972 return -EINVAL; 4973 4974 if (attr->btf_flags & BPF_F_TOKEN_FD) { 4975 token = bpf_token_get_from_fd(attr->btf_token_fd); 4976 if (IS_ERR(token)) 4977 return PTR_ERR(token); 4978 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { 4979 bpf_token_put(token); 4980 token = NULL; 4981 } 4982 } 4983 4984 if (!bpf_token_capable(token, CAP_BPF)) { 4985 bpf_token_put(token); 4986 return -EPERM; 4987 } 4988 4989 bpf_token_put(token); 4990 4991 return btf_new_fd(attr, uattr, uattr_size); 4992 } 4993 4994 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id 4995 4996 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 4997 { 4998 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 4999 return -EINVAL; 5000 5001 if (!capable(CAP_SYS_ADMIN)) 5002 return -EPERM; 5003 5004 return btf_get_fd_by_id(attr->btf_id); 5005 } 5006 5007 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 5008 union bpf_attr __user *uattr, 5009 u32 prog_id, u32 fd_type, 5010 const char *buf, u64 probe_offset, 5011 u64 probe_addr) 5012 { 5013 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 5014 u32 len = buf ? strlen(buf) : 0, input_len; 5015 int err = 0; 5016 5017 if (put_user(len, &uattr->task_fd_query.buf_len)) 5018 return -EFAULT; 5019 input_len = attr->task_fd_query.buf_len; 5020 if (input_len && ubuf) { 5021 if (!len) { 5022 /* nothing to copy, just make ubuf NULL terminated */ 5023 char zero = '\0'; 5024 5025 if (put_user(zero, ubuf)) 5026 return -EFAULT; 5027 } else if (input_len >= len + 1) { 5028 /* ubuf can hold the string with NULL terminator */ 5029 if (copy_to_user(ubuf, buf, len + 1)) 5030 return -EFAULT; 5031 } else { 5032 /* ubuf cannot hold the string with NULL terminator, 5033 * do a partial copy with NULL terminator. 5034 */ 5035 char zero = '\0'; 5036 5037 err = -ENOSPC; 5038 if (copy_to_user(ubuf, buf, input_len - 1)) 5039 return -EFAULT; 5040 if (put_user(zero, ubuf + input_len - 1)) 5041 return -EFAULT; 5042 } 5043 } 5044 5045 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 5046 put_user(fd_type, &uattr->task_fd_query.fd_type) || 5047 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 5048 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 5049 return -EFAULT; 5050 5051 return err; 5052 } 5053 5054 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 5055 5056 static int bpf_task_fd_query(const union bpf_attr *attr, 5057 union bpf_attr __user *uattr) 5058 { 5059 pid_t pid = attr->task_fd_query.pid; 5060 u32 fd = attr->task_fd_query.fd; 5061 const struct perf_event *event; 5062 struct task_struct *task; 5063 struct file *file; 5064 int err; 5065 5066 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 5067 return -EINVAL; 5068 5069 if (!capable(CAP_SYS_ADMIN)) 5070 return -EPERM; 5071 5072 if (attr->task_fd_query.flags != 0) 5073 return -EINVAL; 5074 5075 rcu_read_lock(); 5076 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 5077 rcu_read_unlock(); 5078 if (!task) 5079 return -ENOENT; 5080 5081 err = 0; 5082 file = fget_task(task, fd); 5083 put_task_struct(task); 5084 if (!file) 5085 return -EBADF; 5086 5087 if (file->f_op == &bpf_link_fops) { 5088 struct bpf_link *link = file->private_data; 5089 5090 if (link->ops == &bpf_raw_tp_link_lops) { 5091 struct bpf_raw_tp_link *raw_tp = 5092 container_of(link, struct bpf_raw_tp_link, link); 5093 struct bpf_raw_event_map *btp = raw_tp->btp; 5094 5095 err = bpf_task_fd_query_copy(attr, uattr, 5096 raw_tp->link.prog->aux->id, 5097 BPF_FD_TYPE_RAW_TRACEPOINT, 5098 btp->tp->name, 0, 0); 5099 goto put_file; 5100 } 5101 goto out_not_supp; 5102 } 5103 5104 event = perf_get_event(file); 5105 if (!IS_ERR(event)) { 5106 u64 probe_offset, probe_addr; 5107 u32 prog_id, fd_type; 5108 const char *buf; 5109 5110 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 5111 &buf, &probe_offset, 5112 &probe_addr, NULL); 5113 if (!err) 5114 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 5115 fd_type, buf, 5116 probe_offset, 5117 probe_addr); 5118 goto put_file; 5119 } 5120 5121 out_not_supp: 5122 err = -ENOTSUPP; 5123 put_file: 5124 fput(file); 5125 return err; 5126 } 5127 5128 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 5129 5130 #define BPF_DO_BATCH(fn, ...) \ 5131 do { \ 5132 if (!fn) { \ 5133 err = -ENOTSUPP; \ 5134 goto err_put; \ 5135 } \ 5136 err = fn(__VA_ARGS__); \ 5137 } while (0) 5138 5139 static int bpf_map_do_batch(const union bpf_attr *attr, 5140 union bpf_attr __user *uattr, 5141 int cmd) 5142 { 5143 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 5144 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 5145 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 5146 struct bpf_map *map; 5147 int err, ufd; 5148 struct fd f; 5149 5150 if (CHECK_ATTR(BPF_MAP_BATCH)) 5151 return -EINVAL; 5152 5153 ufd = attr->batch.map_fd; 5154 f = fdget(ufd); 5155 map = __bpf_map_get(f); 5156 if (IS_ERR(map)) 5157 return PTR_ERR(map); 5158 if (has_write) 5159 bpf_map_write_active_inc(map); 5160 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 5161 err = -EPERM; 5162 goto err_put; 5163 } 5164 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 5165 err = -EPERM; 5166 goto err_put; 5167 } 5168 5169 if (cmd == BPF_MAP_LOOKUP_BATCH) 5170 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); 5171 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 5172 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); 5173 else if (cmd == BPF_MAP_UPDATE_BATCH) 5174 BPF_DO_BATCH(map->ops->map_update_batch, map, f.file, attr, uattr); 5175 else 5176 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); 5177 err_put: 5178 if (has_write) { 5179 maybe_wait_bpf_programs(map); 5180 bpf_map_write_active_dec(map); 5181 } 5182 fdput(f); 5183 return err; 5184 } 5185 5186 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid 5187 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 5188 { 5189 struct bpf_prog *prog; 5190 int ret; 5191 5192 if (CHECK_ATTR(BPF_LINK_CREATE)) 5193 return -EINVAL; 5194 5195 if (attr->link_create.attach_type == BPF_STRUCT_OPS) 5196 return bpf_struct_ops_link_create(attr); 5197 5198 prog = bpf_prog_get(attr->link_create.prog_fd); 5199 if (IS_ERR(prog)) 5200 return PTR_ERR(prog); 5201 5202 ret = bpf_prog_attach_check_attach_type(prog, 5203 attr->link_create.attach_type); 5204 if (ret) 5205 goto out; 5206 5207 switch (prog->type) { 5208 case BPF_PROG_TYPE_CGROUP_SKB: 5209 case BPF_PROG_TYPE_CGROUP_SOCK: 5210 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 5211 case BPF_PROG_TYPE_SOCK_OPS: 5212 case BPF_PROG_TYPE_CGROUP_DEVICE: 5213 case BPF_PROG_TYPE_CGROUP_SYSCTL: 5214 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 5215 ret = cgroup_bpf_link_attach(attr, prog); 5216 break; 5217 case BPF_PROG_TYPE_EXT: 5218 ret = bpf_tracing_prog_attach(prog, 5219 attr->link_create.target_fd, 5220 attr->link_create.target_btf_id, 5221 attr->link_create.tracing.cookie); 5222 break; 5223 case BPF_PROG_TYPE_LSM: 5224 case BPF_PROG_TYPE_TRACING: 5225 if (attr->link_create.attach_type != prog->expected_attach_type) { 5226 ret = -EINVAL; 5227 goto out; 5228 } 5229 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 5230 ret = bpf_raw_tp_link_attach(prog, NULL); 5231 else if (prog->expected_attach_type == BPF_TRACE_ITER) 5232 ret = bpf_iter_link_attach(attr, uattr, prog); 5233 else if (prog->expected_attach_type == BPF_LSM_CGROUP) 5234 ret = cgroup_bpf_link_attach(attr, prog); 5235 else 5236 ret = bpf_tracing_prog_attach(prog, 5237 attr->link_create.target_fd, 5238 attr->link_create.target_btf_id, 5239 attr->link_create.tracing.cookie); 5240 break; 5241 case BPF_PROG_TYPE_FLOW_DISSECTOR: 5242 case BPF_PROG_TYPE_SK_LOOKUP: 5243 ret = netns_bpf_link_create(attr, prog); 5244 break; 5245 #ifdef CONFIG_NET 5246 case BPF_PROG_TYPE_XDP: 5247 ret = bpf_xdp_link_attach(attr, prog); 5248 break; 5249 case BPF_PROG_TYPE_SCHED_CLS: 5250 if (attr->link_create.attach_type == BPF_TCX_INGRESS || 5251 attr->link_create.attach_type == BPF_TCX_EGRESS) 5252 ret = tcx_link_attach(attr, prog); 5253 else 5254 ret = netkit_link_attach(attr, prog); 5255 break; 5256 case BPF_PROG_TYPE_NETFILTER: 5257 ret = bpf_nf_link_attach(attr, prog); 5258 break; 5259 #endif 5260 case BPF_PROG_TYPE_PERF_EVENT: 5261 case BPF_PROG_TYPE_TRACEPOINT: 5262 ret = bpf_perf_link_attach(attr, prog); 5263 break; 5264 case BPF_PROG_TYPE_KPROBE: 5265 if (attr->link_create.attach_type == BPF_PERF_EVENT) 5266 ret = bpf_perf_link_attach(attr, prog); 5267 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI) 5268 ret = bpf_kprobe_multi_link_attach(attr, prog); 5269 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI) 5270 ret = bpf_uprobe_multi_link_attach(attr, prog); 5271 break; 5272 default: 5273 ret = -EINVAL; 5274 } 5275 5276 out: 5277 if (ret < 0) 5278 bpf_prog_put(prog); 5279 return ret; 5280 } 5281 5282 static int link_update_map(struct bpf_link *link, union bpf_attr *attr) 5283 { 5284 struct bpf_map *new_map, *old_map = NULL; 5285 int ret; 5286 5287 new_map = bpf_map_get(attr->link_update.new_map_fd); 5288 if (IS_ERR(new_map)) 5289 return PTR_ERR(new_map); 5290 5291 if (attr->link_update.flags & BPF_F_REPLACE) { 5292 old_map = bpf_map_get(attr->link_update.old_map_fd); 5293 if (IS_ERR(old_map)) { 5294 ret = PTR_ERR(old_map); 5295 goto out_put; 5296 } 5297 } else if (attr->link_update.old_map_fd) { 5298 ret = -EINVAL; 5299 goto out_put; 5300 } 5301 5302 ret = link->ops->update_map(link, new_map, old_map); 5303 5304 if (old_map) 5305 bpf_map_put(old_map); 5306 out_put: 5307 bpf_map_put(new_map); 5308 return ret; 5309 } 5310 5311 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 5312 5313 static int link_update(union bpf_attr *attr) 5314 { 5315 struct bpf_prog *old_prog = NULL, *new_prog; 5316 struct bpf_link *link; 5317 u32 flags; 5318 int ret; 5319 5320 if (CHECK_ATTR(BPF_LINK_UPDATE)) 5321 return -EINVAL; 5322 5323 flags = attr->link_update.flags; 5324 if (flags & ~BPF_F_REPLACE) 5325 return -EINVAL; 5326 5327 link = bpf_link_get_from_fd(attr->link_update.link_fd); 5328 if (IS_ERR(link)) 5329 return PTR_ERR(link); 5330 5331 if (link->ops->update_map) { 5332 ret = link_update_map(link, attr); 5333 goto out_put_link; 5334 } 5335 5336 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 5337 if (IS_ERR(new_prog)) { 5338 ret = PTR_ERR(new_prog); 5339 goto out_put_link; 5340 } 5341 5342 if (flags & BPF_F_REPLACE) { 5343 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 5344 if (IS_ERR(old_prog)) { 5345 ret = PTR_ERR(old_prog); 5346 old_prog = NULL; 5347 goto out_put_progs; 5348 } 5349 } else if (attr->link_update.old_prog_fd) { 5350 ret = -EINVAL; 5351 goto out_put_progs; 5352 } 5353 5354 if (link->ops->update_prog) 5355 ret = link->ops->update_prog(link, new_prog, old_prog); 5356 else 5357 ret = -EINVAL; 5358 5359 out_put_progs: 5360 if (old_prog) 5361 bpf_prog_put(old_prog); 5362 if (ret) 5363 bpf_prog_put(new_prog); 5364 out_put_link: 5365 bpf_link_put_direct(link); 5366 return ret; 5367 } 5368 5369 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 5370 5371 static int link_detach(union bpf_attr *attr) 5372 { 5373 struct bpf_link *link; 5374 int ret; 5375 5376 if (CHECK_ATTR(BPF_LINK_DETACH)) 5377 return -EINVAL; 5378 5379 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 5380 if (IS_ERR(link)) 5381 return PTR_ERR(link); 5382 5383 if (link->ops->detach) 5384 ret = link->ops->detach(link); 5385 else 5386 ret = -EOPNOTSUPP; 5387 5388 bpf_link_put_direct(link); 5389 return ret; 5390 } 5391 5392 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 5393 { 5394 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 5395 } 5396 5397 struct bpf_link *bpf_link_by_id(u32 id) 5398 { 5399 struct bpf_link *link; 5400 5401 if (!id) 5402 return ERR_PTR(-ENOENT); 5403 5404 spin_lock_bh(&link_idr_lock); 5405 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 5406 link = idr_find(&link_idr, id); 5407 if (link) { 5408 if (link->id) 5409 link = bpf_link_inc_not_zero(link); 5410 else 5411 link = ERR_PTR(-EAGAIN); 5412 } else { 5413 link = ERR_PTR(-ENOENT); 5414 } 5415 spin_unlock_bh(&link_idr_lock); 5416 return link; 5417 } 5418 5419 struct bpf_link *bpf_link_get_curr_or_next(u32 *id) 5420 { 5421 struct bpf_link *link; 5422 5423 spin_lock_bh(&link_idr_lock); 5424 again: 5425 link = idr_get_next(&link_idr, id); 5426 if (link) { 5427 link = bpf_link_inc_not_zero(link); 5428 if (IS_ERR(link)) { 5429 (*id)++; 5430 goto again; 5431 } 5432 } 5433 spin_unlock_bh(&link_idr_lock); 5434 5435 return link; 5436 } 5437 5438 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 5439 5440 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 5441 { 5442 struct bpf_link *link; 5443 u32 id = attr->link_id; 5444 int fd; 5445 5446 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 5447 return -EINVAL; 5448 5449 if (!capable(CAP_SYS_ADMIN)) 5450 return -EPERM; 5451 5452 link = bpf_link_by_id(id); 5453 if (IS_ERR(link)) 5454 return PTR_ERR(link); 5455 5456 fd = bpf_link_new_fd(link); 5457 if (fd < 0) 5458 bpf_link_put_direct(link); 5459 5460 return fd; 5461 } 5462 5463 DEFINE_MUTEX(bpf_stats_enabled_mutex); 5464 5465 static int bpf_stats_release(struct inode *inode, struct file *file) 5466 { 5467 mutex_lock(&bpf_stats_enabled_mutex); 5468 static_key_slow_dec(&bpf_stats_enabled_key.key); 5469 mutex_unlock(&bpf_stats_enabled_mutex); 5470 return 0; 5471 } 5472 5473 static const struct file_operations bpf_stats_fops = { 5474 .release = bpf_stats_release, 5475 }; 5476 5477 static int bpf_enable_runtime_stats(void) 5478 { 5479 int fd; 5480 5481 mutex_lock(&bpf_stats_enabled_mutex); 5482 5483 /* Set a very high limit to avoid overflow */ 5484 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 5485 mutex_unlock(&bpf_stats_enabled_mutex); 5486 return -EBUSY; 5487 } 5488 5489 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 5490 if (fd >= 0) 5491 static_key_slow_inc(&bpf_stats_enabled_key.key); 5492 5493 mutex_unlock(&bpf_stats_enabled_mutex); 5494 return fd; 5495 } 5496 5497 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 5498 5499 static int bpf_enable_stats(union bpf_attr *attr) 5500 { 5501 5502 if (CHECK_ATTR(BPF_ENABLE_STATS)) 5503 return -EINVAL; 5504 5505 if (!capable(CAP_SYS_ADMIN)) 5506 return -EPERM; 5507 5508 switch (attr->enable_stats.type) { 5509 case BPF_STATS_RUN_TIME: 5510 return bpf_enable_runtime_stats(); 5511 default: 5512 break; 5513 } 5514 return -EINVAL; 5515 } 5516 5517 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 5518 5519 static int bpf_iter_create(union bpf_attr *attr) 5520 { 5521 struct bpf_link *link; 5522 int err; 5523 5524 if (CHECK_ATTR(BPF_ITER_CREATE)) 5525 return -EINVAL; 5526 5527 if (attr->iter_create.flags) 5528 return -EINVAL; 5529 5530 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 5531 if (IS_ERR(link)) 5532 return PTR_ERR(link); 5533 5534 err = bpf_iter_new_fd(link); 5535 bpf_link_put_direct(link); 5536 5537 return err; 5538 } 5539 5540 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 5541 5542 static int bpf_prog_bind_map(union bpf_attr *attr) 5543 { 5544 struct bpf_prog *prog; 5545 struct bpf_map *map; 5546 struct bpf_map **used_maps_old, **used_maps_new; 5547 int i, ret = 0; 5548 5549 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 5550 return -EINVAL; 5551 5552 if (attr->prog_bind_map.flags) 5553 return -EINVAL; 5554 5555 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 5556 if (IS_ERR(prog)) 5557 return PTR_ERR(prog); 5558 5559 map = bpf_map_get(attr->prog_bind_map.map_fd); 5560 if (IS_ERR(map)) { 5561 ret = PTR_ERR(map); 5562 goto out_prog_put; 5563 } 5564 5565 mutex_lock(&prog->aux->used_maps_mutex); 5566 5567 used_maps_old = prog->aux->used_maps; 5568 5569 for (i = 0; i < prog->aux->used_map_cnt; i++) 5570 if (used_maps_old[i] == map) { 5571 bpf_map_put(map); 5572 goto out_unlock; 5573 } 5574 5575 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 5576 sizeof(used_maps_new[0]), 5577 GFP_KERNEL); 5578 if (!used_maps_new) { 5579 ret = -ENOMEM; 5580 goto out_unlock; 5581 } 5582 5583 /* The bpf program will not access the bpf map, but for the sake of 5584 * simplicity, increase sleepable_refcnt for sleepable program as well. 5585 */ 5586 if (prog->sleepable) 5587 atomic64_inc(&map->sleepable_refcnt); 5588 memcpy(used_maps_new, used_maps_old, 5589 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 5590 used_maps_new[prog->aux->used_map_cnt] = map; 5591 5592 prog->aux->used_map_cnt++; 5593 prog->aux->used_maps = used_maps_new; 5594 5595 kfree(used_maps_old); 5596 5597 out_unlock: 5598 mutex_unlock(&prog->aux->used_maps_mutex); 5599 5600 if (ret) 5601 bpf_map_put(map); 5602 out_prog_put: 5603 bpf_prog_put(prog); 5604 return ret; 5605 } 5606 5607 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd 5608 5609 static int token_create(union bpf_attr *attr) 5610 { 5611 if (CHECK_ATTR(BPF_TOKEN_CREATE)) 5612 return -EINVAL; 5613 5614 /* no flags are supported yet */ 5615 if (attr->token_create.flags) 5616 return -EINVAL; 5617 5618 return bpf_token_create(attr); 5619 } 5620 5621 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) 5622 { 5623 union bpf_attr attr; 5624 int err; 5625 5626 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 5627 if (err) 5628 return err; 5629 size = min_t(u32, size, sizeof(attr)); 5630 5631 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 5632 memset(&attr, 0, sizeof(attr)); 5633 if (copy_from_bpfptr(&attr, uattr, size) != 0) 5634 return -EFAULT; 5635 5636 err = security_bpf(cmd, &attr, size); 5637 if (err < 0) 5638 return err; 5639 5640 switch (cmd) { 5641 case BPF_MAP_CREATE: 5642 err = map_create(&attr); 5643 break; 5644 case BPF_MAP_LOOKUP_ELEM: 5645 err = map_lookup_elem(&attr); 5646 break; 5647 case BPF_MAP_UPDATE_ELEM: 5648 err = map_update_elem(&attr, uattr); 5649 break; 5650 case BPF_MAP_DELETE_ELEM: 5651 err = map_delete_elem(&attr, uattr); 5652 break; 5653 case BPF_MAP_GET_NEXT_KEY: 5654 err = map_get_next_key(&attr); 5655 break; 5656 case BPF_MAP_FREEZE: 5657 err = map_freeze(&attr); 5658 break; 5659 case BPF_PROG_LOAD: 5660 err = bpf_prog_load(&attr, uattr, size); 5661 break; 5662 case BPF_OBJ_PIN: 5663 err = bpf_obj_pin(&attr); 5664 break; 5665 case BPF_OBJ_GET: 5666 err = bpf_obj_get(&attr); 5667 break; 5668 case BPF_PROG_ATTACH: 5669 err = bpf_prog_attach(&attr); 5670 break; 5671 case BPF_PROG_DETACH: 5672 err = bpf_prog_detach(&attr); 5673 break; 5674 case BPF_PROG_QUERY: 5675 err = bpf_prog_query(&attr, uattr.user); 5676 break; 5677 case BPF_PROG_TEST_RUN: 5678 err = bpf_prog_test_run(&attr, uattr.user); 5679 break; 5680 case BPF_PROG_GET_NEXT_ID: 5681 err = bpf_obj_get_next_id(&attr, uattr.user, 5682 &prog_idr, &prog_idr_lock); 5683 break; 5684 case BPF_MAP_GET_NEXT_ID: 5685 err = bpf_obj_get_next_id(&attr, uattr.user, 5686 &map_idr, &map_idr_lock); 5687 break; 5688 case BPF_BTF_GET_NEXT_ID: 5689 err = bpf_obj_get_next_id(&attr, uattr.user, 5690 &btf_idr, &btf_idr_lock); 5691 break; 5692 case BPF_PROG_GET_FD_BY_ID: 5693 err = bpf_prog_get_fd_by_id(&attr); 5694 break; 5695 case BPF_MAP_GET_FD_BY_ID: 5696 err = bpf_map_get_fd_by_id(&attr); 5697 break; 5698 case BPF_OBJ_GET_INFO_BY_FD: 5699 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 5700 break; 5701 case BPF_RAW_TRACEPOINT_OPEN: 5702 err = bpf_raw_tracepoint_open(&attr); 5703 break; 5704 case BPF_BTF_LOAD: 5705 err = bpf_btf_load(&attr, uattr, size); 5706 break; 5707 case BPF_BTF_GET_FD_BY_ID: 5708 err = bpf_btf_get_fd_by_id(&attr); 5709 break; 5710 case BPF_TASK_FD_QUERY: 5711 err = bpf_task_fd_query(&attr, uattr.user); 5712 break; 5713 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 5714 err = map_lookup_and_delete_elem(&attr); 5715 break; 5716 case BPF_MAP_LOOKUP_BATCH: 5717 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 5718 break; 5719 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 5720 err = bpf_map_do_batch(&attr, uattr.user, 5721 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 5722 break; 5723 case BPF_MAP_UPDATE_BATCH: 5724 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 5725 break; 5726 case BPF_MAP_DELETE_BATCH: 5727 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 5728 break; 5729 case BPF_LINK_CREATE: 5730 err = link_create(&attr, uattr); 5731 break; 5732 case BPF_LINK_UPDATE: 5733 err = link_update(&attr); 5734 break; 5735 case BPF_LINK_GET_FD_BY_ID: 5736 err = bpf_link_get_fd_by_id(&attr); 5737 break; 5738 case BPF_LINK_GET_NEXT_ID: 5739 err = bpf_obj_get_next_id(&attr, uattr.user, 5740 &link_idr, &link_idr_lock); 5741 break; 5742 case BPF_ENABLE_STATS: 5743 err = bpf_enable_stats(&attr); 5744 break; 5745 case BPF_ITER_CREATE: 5746 err = bpf_iter_create(&attr); 5747 break; 5748 case BPF_LINK_DETACH: 5749 err = link_detach(&attr); 5750 break; 5751 case BPF_PROG_BIND_MAP: 5752 err = bpf_prog_bind_map(&attr); 5753 break; 5754 case BPF_TOKEN_CREATE: 5755 err = token_create(&attr); 5756 break; 5757 default: 5758 err = -EINVAL; 5759 break; 5760 } 5761 5762 return err; 5763 } 5764 5765 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 5766 { 5767 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 5768 } 5769 5770 static bool syscall_prog_is_valid_access(int off, int size, 5771 enum bpf_access_type type, 5772 const struct bpf_prog *prog, 5773 struct bpf_insn_access_aux *info) 5774 { 5775 if (off < 0 || off >= U16_MAX) 5776 return false; 5777 if (off % size != 0) 5778 return false; 5779 return true; 5780 } 5781 5782 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 5783 { 5784 switch (cmd) { 5785 case BPF_MAP_CREATE: 5786 case BPF_MAP_DELETE_ELEM: 5787 case BPF_MAP_UPDATE_ELEM: 5788 case BPF_MAP_FREEZE: 5789 case BPF_MAP_GET_FD_BY_ID: 5790 case BPF_PROG_LOAD: 5791 case BPF_BTF_LOAD: 5792 case BPF_LINK_CREATE: 5793 case BPF_RAW_TRACEPOINT_OPEN: 5794 break; 5795 default: 5796 return -EINVAL; 5797 } 5798 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 5799 } 5800 5801 5802 /* To shut up -Wmissing-prototypes. 5803 * This function is used by the kernel light skeleton 5804 * to load bpf programs when modules are loaded or during kernel boot. 5805 * See tools/lib/bpf/skel_internal.h 5806 */ 5807 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); 5808 5809 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5810 { 5811 struct bpf_prog * __maybe_unused prog; 5812 struct bpf_tramp_run_ctx __maybe_unused run_ctx; 5813 5814 switch (cmd) { 5815 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 5816 case BPF_PROG_TEST_RUN: 5817 if (attr->test.data_in || attr->test.data_out || 5818 attr->test.ctx_out || attr->test.duration || 5819 attr->test.repeat || attr->test.flags) 5820 return -EINVAL; 5821 5822 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 5823 if (IS_ERR(prog)) 5824 return PTR_ERR(prog); 5825 5826 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 5827 attr->test.ctx_size_in > U16_MAX) { 5828 bpf_prog_put(prog); 5829 return -EINVAL; 5830 } 5831 5832 run_ctx.bpf_cookie = 0; 5833 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { 5834 /* recursion detected */ 5835 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); 5836 bpf_prog_put(prog); 5837 return -EBUSY; 5838 } 5839 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 5840 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, 5841 &run_ctx); 5842 bpf_prog_put(prog); 5843 return 0; 5844 #endif 5845 default: 5846 return ____bpf_sys_bpf(cmd, attr, size); 5847 } 5848 } 5849 EXPORT_SYMBOL(kern_sys_bpf); 5850 5851 static const struct bpf_func_proto bpf_sys_bpf_proto = { 5852 .func = bpf_sys_bpf, 5853 .gpl_only = false, 5854 .ret_type = RET_INTEGER, 5855 .arg1_type = ARG_ANYTHING, 5856 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 5857 .arg3_type = ARG_CONST_SIZE, 5858 }; 5859 5860 const struct bpf_func_proto * __weak 5861 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5862 { 5863 return bpf_base_func_proto(func_id, prog); 5864 } 5865 5866 BPF_CALL_1(bpf_sys_close, u32, fd) 5867 { 5868 /* When bpf program calls this helper there should not be 5869 * an fdget() without matching completed fdput(). 5870 * This helper is allowed in the following callchain only: 5871 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 5872 */ 5873 return close_fd(fd); 5874 } 5875 5876 static const struct bpf_func_proto bpf_sys_close_proto = { 5877 .func = bpf_sys_close, 5878 .gpl_only = false, 5879 .ret_type = RET_INTEGER, 5880 .arg1_type = ARG_ANYTHING, 5881 }; 5882 5883 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 5884 { 5885 if (flags) 5886 return -EINVAL; 5887 5888 if (name_sz <= 1 || name[name_sz - 1]) 5889 return -EINVAL; 5890 5891 if (!bpf_dump_raw_ok(current_cred())) 5892 return -EPERM; 5893 5894 *res = kallsyms_lookup_name(name); 5895 return *res ? 0 : -ENOENT; 5896 } 5897 5898 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 5899 .func = bpf_kallsyms_lookup_name, 5900 .gpl_only = false, 5901 .ret_type = RET_INTEGER, 5902 .arg1_type = ARG_PTR_TO_MEM, 5903 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 5904 .arg3_type = ARG_ANYTHING, 5905 .arg4_type = ARG_PTR_TO_LONG, 5906 }; 5907 5908 static const struct bpf_func_proto * 5909 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5910 { 5911 switch (func_id) { 5912 case BPF_FUNC_sys_bpf: 5913 return !bpf_token_capable(prog->aux->token, CAP_PERFMON) 5914 ? NULL : &bpf_sys_bpf_proto; 5915 case BPF_FUNC_btf_find_by_name_kind: 5916 return &bpf_btf_find_by_name_kind_proto; 5917 case BPF_FUNC_sys_close: 5918 return &bpf_sys_close_proto; 5919 case BPF_FUNC_kallsyms_lookup_name: 5920 return &bpf_kallsyms_lookup_name_proto; 5921 default: 5922 return tracing_prog_func_proto(func_id, prog); 5923 } 5924 } 5925 5926 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 5927 .get_func_proto = syscall_prog_func_proto, 5928 .is_valid_access = syscall_prog_is_valid_access, 5929 }; 5930 5931 const struct bpf_prog_ops bpf_syscall_prog_ops = { 5932 .test_run = bpf_prog_test_run_syscall, 5933 }; 5934 5935 #ifdef CONFIG_SYSCTL 5936 static int bpf_stats_handler(struct ctl_table *table, int write, 5937 void *buffer, size_t *lenp, loff_t *ppos) 5938 { 5939 struct static_key *key = (struct static_key *)table->data; 5940 static int saved_val; 5941 int val, ret; 5942 struct ctl_table tmp = { 5943 .data = &val, 5944 .maxlen = sizeof(val), 5945 .mode = table->mode, 5946 .extra1 = SYSCTL_ZERO, 5947 .extra2 = SYSCTL_ONE, 5948 }; 5949 5950 if (write && !capable(CAP_SYS_ADMIN)) 5951 return -EPERM; 5952 5953 mutex_lock(&bpf_stats_enabled_mutex); 5954 val = saved_val; 5955 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 5956 if (write && !ret && val != saved_val) { 5957 if (val) 5958 static_key_slow_inc(key); 5959 else 5960 static_key_slow_dec(key); 5961 saved_val = val; 5962 } 5963 mutex_unlock(&bpf_stats_enabled_mutex); 5964 return ret; 5965 } 5966 5967 void __weak unpriv_ebpf_notify(int new_state) 5968 { 5969 } 5970 5971 static int bpf_unpriv_handler(struct ctl_table *table, int write, 5972 void *buffer, size_t *lenp, loff_t *ppos) 5973 { 5974 int ret, unpriv_enable = *(int *)table->data; 5975 bool locked_state = unpriv_enable == 1; 5976 struct ctl_table tmp = *table; 5977 5978 if (write && !capable(CAP_SYS_ADMIN)) 5979 return -EPERM; 5980 5981 tmp.data = &unpriv_enable; 5982 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 5983 if (write && !ret) { 5984 if (locked_state && unpriv_enable != 1) 5985 return -EPERM; 5986 *(int *)table->data = unpriv_enable; 5987 } 5988 5989 if (write) 5990 unpriv_ebpf_notify(unpriv_enable); 5991 5992 return ret; 5993 } 5994 5995 static struct ctl_table bpf_syscall_table[] = { 5996 { 5997 .procname = "unprivileged_bpf_disabled", 5998 .data = &sysctl_unprivileged_bpf_disabled, 5999 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), 6000 .mode = 0644, 6001 .proc_handler = bpf_unpriv_handler, 6002 .extra1 = SYSCTL_ZERO, 6003 .extra2 = SYSCTL_TWO, 6004 }, 6005 { 6006 .procname = "bpf_stats_enabled", 6007 .data = &bpf_stats_enabled_key.key, 6008 .mode = 0644, 6009 .proc_handler = bpf_stats_handler, 6010 }, 6011 { } 6012 }; 6013 6014 static int __init bpf_syscall_sysctl_init(void) 6015 { 6016 register_sysctl_init("kernel", bpf_syscall_table); 6017 return 0; 6018 } 6019 late_initcall(bpf_syscall_sysctl_init); 6020 #endif /* CONFIG_SYSCTL */ 6021