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