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 #include <linux/tracepoint.h> 39 #include <linux/overflow.h> 40 41 #include <net/netfilter/nf_bpf_link.h> 42 #include <net/netkit.h> 43 #include <net/tcx.h> 44 45 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ 46 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ 47 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 48 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) 49 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) 50 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ 51 IS_FD_HASH(map)) 52 53 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) 54 55 DEFINE_PER_CPU(int, bpf_prog_active); 56 static DEFINE_IDR(prog_idr); 57 static DEFINE_SPINLOCK(prog_idr_lock); 58 static DEFINE_IDR(map_idr); 59 static DEFINE_SPINLOCK(map_idr_lock); 60 static DEFINE_IDR(link_idr); 61 static DEFINE_SPINLOCK(link_idr_lock); 62 63 int sysctl_unprivileged_bpf_disabled __read_mostly = 64 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; 65 66 static const struct bpf_map_ops * const bpf_map_types[] = { 67 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 68 #define BPF_MAP_TYPE(_id, _ops) \ 69 [_id] = &_ops, 70 #define BPF_LINK_TYPE(_id, _name) 71 #include <linux/bpf_types.h> 72 #undef BPF_PROG_TYPE 73 #undef BPF_MAP_TYPE 74 #undef BPF_LINK_TYPE 75 }; 76 77 /* 78 * If we're handed a bigger struct than we know of, ensure all the unknown bits 79 * are 0 - i.e. new user-space does not rely on any kernel feature extensions 80 * we don't know about yet. 81 * 82 * There is a ToCToU between this function call and the following 83 * copy_from_user() call. However, this is not a concern since this function is 84 * meant to be a future-proofing of bits. 85 */ 86 int bpf_check_uarg_tail_zero(bpfptr_t uaddr, 87 size_t expected_size, 88 size_t actual_size) 89 { 90 int res; 91 92 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ 93 return -E2BIG; 94 95 if (actual_size <= expected_size) 96 return 0; 97 98 if (uaddr.is_kernel) 99 res = memchr_inv(uaddr.kernel + expected_size, 0, 100 actual_size - expected_size) == NULL; 101 else 102 res = check_zeroed_user(uaddr.user + expected_size, 103 actual_size - expected_size); 104 if (res < 0) 105 return res; 106 return res ? 0 : -E2BIG; 107 } 108 109 const struct bpf_map_ops bpf_map_offload_ops = { 110 .map_meta_equal = bpf_map_meta_equal, 111 .map_alloc = bpf_map_offload_map_alloc, 112 .map_free = bpf_map_offload_map_free, 113 .map_check_btf = map_check_no_btf, 114 .map_mem_usage = bpf_map_offload_map_mem_usage, 115 }; 116 117 static void bpf_map_write_active_inc(struct bpf_map *map) 118 { 119 atomic64_inc(&map->writecnt); 120 } 121 122 static void bpf_map_write_active_dec(struct bpf_map *map) 123 { 124 atomic64_dec(&map->writecnt); 125 } 126 127 bool bpf_map_write_active(const struct bpf_map *map) 128 { 129 return atomic64_read(&map->writecnt) != 0; 130 } 131 132 static u32 bpf_map_value_size(const struct bpf_map *map) 133 { 134 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 135 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || 136 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || 137 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) 138 return round_up(map->value_size, 8) * num_possible_cpus(); 139 else if (IS_FD_MAP(map)) 140 return sizeof(u32); 141 else 142 return map->value_size; 143 } 144 145 static void maybe_wait_bpf_programs(struct bpf_map *map) 146 { 147 /* Wait for any running non-sleepable BPF programs to complete so that 148 * userspace, when we return to it, knows that all non-sleepable 149 * programs that could be running use the new map value. For sleepable 150 * BPF programs, synchronize_rcu_tasks_trace() should be used to wait 151 * for the completions of these programs, but considering the waiting 152 * time can be very long and userspace may think it will hang forever, 153 * so don't handle sleepable BPF programs now. 154 */ 155 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || 156 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) 157 synchronize_rcu(); 158 } 159 160 static void unpin_uptr_kaddr(void *kaddr) 161 { 162 if (kaddr) 163 unpin_user_page(virt_to_page(kaddr)); 164 } 165 166 static void __bpf_obj_unpin_uptrs(struct btf_record *rec, u32 cnt, void *obj) 167 { 168 const struct btf_field *field; 169 void **uptr_addr; 170 int i; 171 172 for (i = 0, field = rec->fields; i < cnt; i++, field++) { 173 if (field->type != BPF_UPTR) 174 continue; 175 176 uptr_addr = obj + field->offset; 177 unpin_uptr_kaddr(*uptr_addr); 178 } 179 } 180 181 static void bpf_obj_unpin_uptrs(struct btf_record *rec, void *obj) 182 { 183 if (!btf_record_has_field(rec, BPF_UPTR)) 184 return; 185 186 __bpf_obj_unpin_uptrs(rec, rec->cnt, obj); 187 } 188 189 static int bpf_obj_pin_uptrs(struct btf_record *rec, void *obj) 190 { 191 const struct btf_field *field; 192 const struct btf_type *t; 193 unsigned long start, end; 194 struct page *page; 195 void **uptr_addr; 196 int i, err; 197 198 if (!btf_record_has_field(rec, BPF_UPTR)) 199 return 0; 200 201 for (i = 0, field = rec->fields; i < rec->cnt; i++, field++) { 202 if (field->type != BPF_UPTR) 203 continue; 204 205 uptr_addr = obj + field->offset; 206 start = *(unsigned long *)uptr_addr; 207 if (!start) 208 continue; 209 210 t = btf_type_by_id(field->kptr.btf, field->kptr.btf_id); 211 /* t->size was checked for zero before */ 212 if (check_add_overflow(start, t->size - 1, &end)) { 213 err = -EFAULT; 214 goto unpin_all; 215 } 216 217 /* The uptr's struct cannot span across two pages */ 218 if ((start & PAGE_MASK) != (end & PAGE_MASK)) { 219 err = -EOPNOTSUPP; 220 goto unpin_all; 221 } 222 223 err = pin_user_pages_fast(start, 1, FOLL_LONGTERM | FOLL_WRITE, &page); 224 if (err != 1) 225 goto unpin_all; 226 227 if (PageHighMem(page)) { 228 err = -EOPNOTSUPP; 229 unpin_user_page(page); 230 goto unpin_all; 231 } 232 233 *uptr_addr = page_address(page) + offset_in_page(start); 234 } 235 236 return 0; 237 238 unpin_all: 239 __bpf_obj_unpin_uptrs(rec, i, obj); 240 return err; 241 } 242 243 static int bpf_map_update_value(struct bpf_map *map, struct file *map_file, 244 void *key, void *value, __u64 flags) 245 { 246 int err; 247 248 /* Need to create a kthread, thus must support schedule */ 249 if (bpf_map_is_offloaded(map)) { 250 return bpf_map_offload_update_elem(map, key, value, flags); 251 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || 252 map->map_type == BPF_MAP_TYPE_ARENA || 253 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 254 return map->ops->map_update_elem(map, key, value, flags); 255 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || 256 map->map_type == BPF_MAP_TYPE_SOCKMAP) { 257 return sock_map_update_elem_sys(map, key, value, flags); 258 } else if (IS_FD_PROG_ARRAY(map)) { 259 return bpf_fd_array_map_update_elem(map, map_file, key, value, 260 flags); 261 } 262 263 bpf_disable_instrumentation(); 264 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 265 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 266 err = bpf_percpu_hash_update(map, key, value, flags); 267 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 268 err = bpf_percpu_array_update(map, key, value, flags); 269 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 270 err = bpf_percpu_cgroup_storage_update(map, key, value, 271 flags); 272 } else if (IS_FD_ARRAY(map)) { 273 err = bpf_fd_array_map_update_elem(map, map_file, key, value, 274 flags); 275 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { 276 err = bpf_fd_htab_map_update_elem(map, map_file, key, value, 277 flags); 278 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 279 /* rcu_read_lock() is not needed */ 280 err = bpf_fd_reuseport_array_update_elem(map, key, value, 281 flags); 282 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 283 map->map_type == BPF_MAP_TYPE_STACK || 284 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 285 err = map->ops->map_push_elem(map, value, flags); 286 } else { 287 err = bpf_obj_pin_uptrs(map->record, value); 288 if (!err) { 289 rcu_read_lock(); 290 err = map->ops->map_update_elem(map, key, value, flags); 291 rcu_read_unlock(); 292 if (err) 293 bpf_obj_unpin_uptrs(map->record, value); 294 } 295 } 296 bpf_enable_instrumentation(); 297 298 return err; 299 } 300 301 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, 302 __u64 flags) 303 { 304 void *ptr; 305 int err; 306 307 if (bpf_map_is_offloaded(map)) 308 return bpf_map_offload_lookup_elem(map, key, value); 309 310 bpf_disable_instrumentation(); 311 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 312 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 313 err = bpf_percpu_hash_copy(map, key, value); 314 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { 315 err = bpf_percpu_array_copy(map, key, value); 316 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { 317 err = bpf_percpu_cgroup_storage_copy(map, key, value); 318 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { 319 err = bpf_stackmap_copy(map, key, value); 320 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { 321 err = bpf_fd_array_map_lookup_elem(map, key, value); 322 } else if (IS_FD_HASH(map)) { 323 err = bpf_fd_htab_map_lookup_elem(map, key, value); 324 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { 325 err = bpf_fd_reuseport_array_lookup_elem(map, key, value); 326 } else if (map->map_type == BPF_MAP_TYPE_QUEUE || 327 map->map_type == BPF_MAP_TYPE_STACK || 328 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 329 err = map->ops->map_peek_elem(map, value); 330 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 331 /* struct_ops map requires directly updating "value" */ 332 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); 333 } else { 334 rcu_read_lock(); 335 if (map->ops->map_lookup_elem_sys_only) 336 ptr = map->ops->map_lookup_elem_sys_only(map, key); 337 else 338 ptr = map->ops->map_lookup_elem(map, key); 339 if (IS_ERR(ptr)) { 340 err = PTR_ERR(ptr); 341 } else if (!ptr) { 342 err = -ENOENT; 343 } else { 344 err = 0; 345 if (flags & BPF_F_LOCK) 346 /* lock 'ptr' and copy everything but lock */ 347 copy_map_value_locked(map, value, ptr, true); 348 else 349 copy_map_value(map, value, ptr); 350 /* mask lock and timer, since value wasn't zero inited */ 351 check_and_init_map_value(map, value); 352 } 353 rcu_read_unlock(); 354 } 355 356 bpf_enable_instrumentation(); 357 358 return err; 359 } 360 361 /* Please, do not use this function outside from the map creation path 362 * (e.g. in map update path) without taking care of setting the active 363 * memory cgroup (see at bpf_map_kmalloc_node() for example). 364 */ 365 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) 366 { 367 /* We really just want to fail instead of triggering OOM killer 368 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, 369 * which is used for lower order allocation requests. 370 * 371 * It has been observed that higher order allocation requests done by 372 * vmalloc with __GFP_NORETRY being set might fail due to not trying 373 * to reclaim memory from the page cache, thus we set 374 * __GFP_RETRY_MAYFAIL to avoid such situations. 375 */ 376 377 gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO); 378 unsigned int flags = 0; 379 unsigned long align = 1; 380 void *area; 381 382 if (size >= SIZE_MAX) 383 return NULL; 384 385 /* kmalloc()'ed memory can't be mmap()'ed */ 386 if (mmapable) { 387 BUG_ON(!PAGE_ALIGNED(size)); 388 align = SHMLBA; 389 flags = VM_USERMAP; 390 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { 391 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, 392 numa_node); 393 if (area != NULL) 394 return area; 395 } 396 397 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, 398 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, 399 flags, numa_node, __builtin_return_address(0)); 400 } 401 402 void *bpf_map_area_alloc(u64 size, int numa_node) 403 { 404 return __bpf_map_area_alloc(size, numa_node, false); 405 } 406 407 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) 408 { 409 return __bpf_map_area_alloc(size, numa_node, true); 410 } 411 412 void bpf_map_area_free(void *area) 413 { 414 kvfree(area); 415 } 416 417 static u32 bpf_map_flags_retain_permanent(u32 flags) 418 { 419 /* Some map creation flags are not tied to the map object but 420 * rather to the map fd instead, so they have no meaning upon 421 * map object inspection since multiple file descriptors with 422 * different (access) properties can exist here. Thus, given 423 * this has zero meaning for the map itself, lets clear these 424 * from here. 425 */ 426 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); 427 } 428 429 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) 430 { 431 map->map_type = attr->map_type; 432 map->key_size = attr->key_size; 433 map->value_size = attr->value_size; 434 map->max_entries = attr->max_entries; 435 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); 436 map->numa_node = bpf_map_attr_numa_node(attr); 437 map->map_extra = attr->map_extra; 438 } 439 440 static int bpf_map_alloc_id(struct bpf_map *map) 441 { 442 int id; 443 444 idr_preload(GFP_KERNEL); 445 spin_lock_bh(&map_idr_lock); 446 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); 447 if (id > 0) 448 map->id = id; 449 spin_unlock_bh(&map_idr_lock); 450 idr_preload_end(); 451 452 if (WARN_ON_ONCE(!id)) 453 return -ENOSPC; 454 455 return id > 0 ? 0 : id; 456 } 457 458 void bpf_map_free_id(struct bpf_map *map) 459 { 460 unsigned long flags; 461 462 /* Offloaded maps are removed from the IDR store when their device 463 * disappears - even if someone holds an fd to them they are unusable, 464 * the memory is gone, all ops will fail; they are simply waiting for 465 * refcnt to drop to be freed. 466 */ 467 if (!map->id) 468 return; 469 470 spin_lock_irqsave(&map_idr_lock, flags); 471 472 idr_remove(&map_idr, map->id); 473 map->id = 0; 474 475 spin_unlock_irqrestore(&map_idr_lock, flags); 476 } 477 478 #ifdef CONFIG_MEMCG 479 static void bpf_map_save_memcg(struct bpf_map *map) 480 { 481 /* Currently if a map is created by a process belonging to the root 482 * memory cgroup, get_obj_cgroup_from_current() will return NULL. 483 * So we have to check map->objcg for being NULL each time it's 484 * being used. 485 */ 486 if (memcg_bpf_enabled()) 487 map->objcg = get_obj_cgroup_from_current(); 488 } 489 490 static void bpf_map_release_memcg(struct bpf_map *map) 491 { 492 if (map->objcg) 493 obj_cgroup_put(map->objcg); 494 } 495 496 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map) 497 { 498 if (map->objcg) 499 return get_mem_cgroup_from_objcg(map->objcg); 500 501 return root_mem_cgroup; 502 } 503 504 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 505 int node) 506 { 507 struct mem_cgroup *memcg, *old_memcg; 508 void *ptr; 509 510 memcg = bpf_map_get_memcg(map); 511 old_memcg = set_active_memcg(memcg); 512 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); 513 set_active_memcg(old_memcg); 514 mem_cgroup_put(memcg); 515 516 return ptr; 517 } 518 519 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) 520 { 521 struct mem_cgroup *memcg, *old_memcg; 522 void *ptr; 523 524 memcg = bpf_map_get_memcg(map); 525 old_memcg = set_active_memcg(memcg); 526 ptr = kzalloc(size, flags | __GFP_ACCOUNT); 527 set_active_memcg(old_memcg); 528 mem_cgroup_put(memcg); 529 530 return ptr; 531 } 532 533 void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size, 534 gfp_t flags) 535 { 536 struct mem_cgroup *memcg, *old_memcg; 537 void *ptr; 538 539 memcg = bpf_map_get_memcg(map); 540 old_memcg = set_active_memcg(memcg); 541 ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT); 542 set_active_memcg(old_memcg); 543 mem_cgroup_put(memcg); 544 545 return ptr; 546 } 547 548 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 549 size_t align, gfp_t flags) 550 { 551 struct mem_cgroup *memcg, *old_memcg; 552 void __percpu *ptr; 553 554 memcg = bpf_map_get_memcg(map); 555 old_memcg = set_active_memcg(memcg); 556 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); 557 set_active_memcg(old_memcg); 558 mem_cgroup_put(memcg); 559 560 return ptr; 561 } 562 563 #else 564 static void bpf_map_save_memcg(struct bpf_map *map) 565 { 566 } 567 568 static void bpf_map_release_memcg(struct bpf_map *map) 569 { 570 } 571 #endif 572 573 static bool can_alloc_pages(void) 574 { 575 return preempt_count() == 0 && !irqs_disabled() && 576 !IS_ENABLED(CONFIG_PREEMPT_RT); 577 } 578 579 static struct page *__bpf_alloc_page(int nid) 580 { 581 if (!can_alloc_pages()) 582 return alloc_pages_nolock(nid, 0); 583 584 return alloc_pages_node(nid, 585 GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT 586 | __GFP_NOWARN, 587 0); 588 } 589 590 int bpf_map_alloc_pages(const struct bpf_map *map, int nid, 591 unsigned long nr_pages, struct page **pages) 592 { 593 unsigned long i, j; 594 struct page *pg; 595 int ret = 0; 596 #ifdef CONFIG_MEMCG 597 struct mem_cgroup *memcg, *old_memcg; 598 599 memcg = bpf_map_get_memcg(map); 600 old_memcg = set_active_memcg(memcg); 601 #endif 602 for (i = 0; i < nr_pages; i++) { 603 pg = __bpf_alloc_page(nid); 604 605 if (pg) { 606 pages[i] = pg; 607 continue; 608 } 609 for (j = 0; j < i; j++) 610 free_pages_nolock(pages[j], 0); 611 ret = -ENOMEM; 612 break; 613 } 614 615 #ifdef CONFIG_MEMCG 616 set_active_memcg(old_memcg); 617 mem_cgroup_put(memcg); 618 #endif 619 return ret; 620 } 621 622 623 static int btf_field_cmp(const void *a, const void *b) 624 { 625 const struct btf_field *f1 = a, *f2 = b; 626 627 if (f1->offset < f2->offset) 628 return -1; 629 else if (f1->offset > f2->offset) 630 return 1; 631 return 0; 632 } 633 634 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, 635 u32 field_mask) 636 { 637 struct btf_field *field; 638 639 if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask)) 640 return NULL; 641 field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); 642 if (!field || !(field->type & field_mask)) 643 return NULL; 644 return field; 645 } 646 647 void btf_record_free(struct btf_record *rec) 648 { 649 int i; 650 651 if (IS_ERR_OR_NULL(rec)) 652 return; 653 for (i = 0; i < rec->cnt; i++) { 654 switch (rec->fields[i].type) { 655 case BPF_KPTR_UNREF: 656 case BPF_KPTR_REF: 657 case BPF_KPTR_PERCPU: 658 case BPF_UPTR: 659 if (rec->fields[i].kptr.module) 660 module_put(rec->fields[i].kptr.module); 661 if (btf_is_kernel(rec->fields[i].kptr.btf)) 662 btf_put(rec->fields[i].kptr.btf); 663 break; 664 case BPF_LIST_HEAD: 665 case BPF_LIST_NODE: 666 case BPF_RB_ROOT: 667 case BPF_RB_NODE: 668 case BPF_SPIN_LOCK: 669 case BPF_RES_SPIN_LOCK: 670 case BPF_TIMER: 671 case BPF_REFCOUNT: 672 case BPF_WORKQUEUE: 673 /* Nothing to release */ 674 break; 675 default: 676 WARN_ON_ONCE(1); 677 continue; 678 } 679 } 680 kfree(rec); 681 } 682 683 void bpf_map_free_record(struct bpf_map *map) 684 { 685 btf_record_free(map->record); 686 map->record = NULL; 687 } 688 689 struct btf_record *btf_record_dup(const struct btf_record *rec) 690 { 691 const struct btf_field *fields; 692 struct btf_record *new_rec; 693 int ret, size, i; 694 695 if (IS_ERR_OR_NULL(rec)) 696 return NULL; 697 size = struct_size(rec, fields, rec->cnt); 698 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); 699 if (!new_rec) 700 return ERR_PTR(-ENOMEM); 701 /* Do a deep copy of the btf_record */ 702 fields = rec->fields; 703 new_rec->cnt = 0; 704 for (i = 0; i < rec->cnt; i++) { 705 switch (fields[i].type) { 706 case BPF_KPTR_UNREF: 707 case BPF_KPTR_REF: 708 case BPF_KPTR_PERCPU: 709 case BPF_UPTR: 710 if (btf_is_kernel(fields[i].kptr.btf)) 711 btf_get(fields[i].kptr.btf); 712 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { 713 ret = -ENXIO; 714 goto free; 715 } 716 break; 717 case BPF_LIST_HEAD: 718 case BPF_LIST_NODE: 719 case BPF_RB_ROOT: 720 case BPF_RB_NODE: 721 case BPF_SPIN_LOCK: 722 case BPF_RES_SPIN_LOCK: 723 case BPF_TIMER: 724 case BPF_REFCOUNT: 725 case BPF_WORKQUEUE: 726 /* Nothing to acquire */ 727 break; 728 default: 729 ret = -EFAULT; 730 WARN_ON_ONCE(1); 731 goto free; 732 } 733 new_rec->cnt++; 734 } 735 return new_rec; 736 free: 737 btf_record_free(new_rec); 738 return ERR_PTR(ret); 739 } 740 741 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) 742 { 743 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); 744 int size; 745 746 if (!a_has_fields && !b_has_fields) 747 return true; 748 if (a_has_fields != b_has_fields) 749 return false; 750 if (rec_a->cnt != rec_b->cnt) 751 return false; 752 size = struct_size(rec_a, fields, rec_a->cnt); 753 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused 754 * members are zeroed out. So memcmp is safe to do without worrying 755 * about padding/unused fields. 756 * 757 * While spin_lock, timer, and kptr have no relation to map BTF, 758 * list_head metadata is specific to map BTF, the btf and value_rec 759 * members in particular. btf is the map BTF, while value_rec points to 760 * btf_record in that map BTF. 761 * 762 * So while by default, we don't rely on the map BTF (which the records 763 * were parsed from) matching for both records, which is not backwards 764 * compatible, in case list_head is part of it, we implicitly rely on 765 * that by way of depending on memcmp succeeding for it. 766 */ 767 return !memcmp(rec_a, rec_b, size); 768 } 769 770 void bpf_obj_free_timer(const struct btf_record *rec, void *obj) 771 { 772 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) 773 return; 774 bpf_timer_cancel_and_free(obj + rec->timer_off); 775 } 776 777 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj) 778 { 779 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE))) 780 return; 781 bpf_wq_cancel_and_free(obj + rec->wq_off); 782 } 783 784 void bpf_obj_free_fields(const struct btf_record *rec, void *obj) 785 { 786 const struct btf_field *fields; 787 int i; 788 789 if (IS_ERR_OR_NULL(rec)) 790 return; 791 fields = rec->fields; 792 for (i = 0; i < rec->cnt; i++) { 793 struct btf_struct_meta *pointee_struct_meta; 794 const struct btf_field *field = &fields[i]; 795 void *field_ptr = obj + field->offset; 796 void *xchgd_field; 797 798 switch (fields[i].type) { 799 case BPF_SPIN_LOCK: 800 case BPF_RES_SPIN_LOCK: 801 break; 802 case BPF_TIMER: 803 bpf_timer_cancel_and_free(field_ptr); 804 break; 805 case BPF_WORKQUEUE: 806 bpf_wq_cancel_and_free(field_ptr); 807 break; 808 case BPF_KPTR_UNREF: 809 WRITE_ONCE(*(u64 *)field_ptr, 0); 810 break; 811 case BPF_KPTR_REF: 812 case BPF_KPTR_PERCPU: 813 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); 814 if (!xchgd_field) 815 break; 816 817 if (!btf_is_kernel(field->kptr.btf)) { 818 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, 819 field->kptr.btf_id); 820 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? 821 pointee_struct_meta->record : NULL, 822 fields[i].type == BPF_KPTR_PERCPU); 823 } else { 824 field->kptr.dtor(xchgd_field); 825 } 826 break; 827 case BPF_UPTR: 828 /* The caller ensured that no one is using the uptr */ 829 unpin_uptr_kaddr(*(void **)field_ptr); 830 break; 831 case BPF_LIST_HEAD: 832 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 833 continue; 834 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); 835 break; 836 case BPF_RB_ROOT: 837 if (WARN_ON_ONCE(rec->spin_lock_off < 0)) 838 continue; 839 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); 840 break; 841 case BPF_LIST_NODE: 842 case BPF_RB_NODE: 843 case BPF_REFCOUNT: 844 break; 845 default: 846 WARN_ON_ONCE(1); 847 continue; 848 } 849 } 850 } 851 852 static void bpf_map_free(struct bpf_map *map) 853 { 854 struct btf_record *rec = map->record; 855 struct btf *btf = map->btf; 856 857 /* implementation dependent freeing. Disabling migration to simplify 858 * the free of values or special fields allocated from bpf memory 859 * allocator. 860 */ 861 migrate_disable(); 862 map->ops->map_free(map); 863 migrate_enable(); 864 865 /* Delay freeing of btf_record for maps, as map_free 866 * callback usually needs access to them. It is better to do it here 867 * than require each callback to do the free itself manually. 868 * 869 * Note that the btf_record stashed in map->inner_map_meta->record was 870 * already freed using the map_free callback for map in map case which 871 * eventually calls bpf_map_free_meta, since inner_map_meta is only a 872 * template bpf_map struct used during verification. 873 */ 874 btf_record_free(rec); 875 /* Delay freeing of btf for maps, as map_free callback may need 876 * struct_meta info which will be freed with btf_put(). 877 */ 878 btf_put(btf); 879 } 880 881 /* called from workqueue */ 882 static void bpf_map_free_deferred(struct work_struct *work) 883 { 884 struct bpf_map *map = container_of(work, struct bpf_map, work); 885 886 security_bpf_map_free(map); 887 bpf_map_release_memcg(map); 888 bpf_map_free(map); 889 } 890 891 static void bpf_map_put_uref(struct bpf_map *map) 892 { 893 if (atomic64_dec_and_test(&map->usercnt)) { 894 if (map->ops->map_release_uref) 895 map->ops->map_release_uref(map); 896 } 897 } 898 899 static void bpf_map_free_in_work(struct bpf_map *map) 900 { 901 INIT_WORK(&map->work, bpf_map_free_deferred); 902 /* Avoid spawning kworkers, since they all might contend 903 * for the same mutex like slab_mutex. 904 */ 905 queue_work(system_unbound_wq, &map->work); 906 } 907 908 static void bpf_map_free_rcu_gp(struct rcu_head *rcu) 909 { 910 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); 911 } 912 913 static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu) 914 { 915 if (rcu_trace_implies_rcu_gp()) 916 bpf_map_free_rcu_gp(rcu); 917 else 918 call_rcu(rcu, bpf_map_free_rcu_gp); 919 } 920 921 /* decrement map refcnt and schedule it for freeing via workqueue 922 * (underlying map implementation ops->map_free() might sleep) 923 */ 924 void bpf_map_put(struct bpf_map *map) 925 { 926 if (atomic64_dec_and_test(&map->refcnt)) { 927 /* bpf_map_free_id() must be called first */ 928 bpf_map_free_id(map); 929 930 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); 931 if (READ_ONCE(map->free_after_mult_rcu_gp)) 932 call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp); 933 else if (READ_ONCE(map->free_after_rcu_gp)) 934 call_rcu(&map->rcu, bpf_map_free_rcu_gp); 935 else 936 bpf_map_free_in_work(map); 937 } 938 } 939 EXPORT_SYMBOL_GPL(bpf_map_put); 940 941 void bpf_map_put_with_uref(struct bpf_map *map) 942 { 943 bpf_map_put_uref(map); 944 bpf_map_put(map); 945 } 946 947 static int bpf_map_release(struct inode *inode, struct file *filp) 948 { 949 struct bpf_map *map = filp->private_data; 950 951 if (map->ops->map_release) 952 map->ops->map_release(map, filp); 953 954 bpf_map_put_with_uref(map); 955 return 0; 956 } 957 958 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) 959 { 960 fmode_t mode = fd_file(f)->f_mode; 961 962 /* Our file permissions may have been overridden by global 963 * map permissions facing syscall side. 964 */ 965 if (READ_ONCE(map->frozen)) 966 mode &= ~FMODE_CAN_WRITE; 967 return mode; 968 } 969 970 #ifdef CONFIG_PROC_FS 971 /* Show the memory usage of a bpf map */ 972 static u64 bpf_map_memory_usage(const struct bpf_map *map) 973 { 974 return map->ops->map_mem_usage(map); 975 } 976 977 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) 978 { 979 struct bpf_map *map = filp->private_data; 980 u32 type = 0, jited = 0; 981 982 if (map_type_contains_progs(map)) { 983 spin_lock(&map->owner.lock); 984 type = map->owner.type; 985 jited = map->owner.jited; 986 spin_unlock(&map->owner.lock); 987 } 988 989 seq_printf(m, 990 "map_type:\t%u\n" 991 "key_size:\t%u\n" 992 "value_size:\t%u\n" 993 "max_entries:\t%u\n" 994 "map_flags:\t%#x\n" 995 "map_extra:\t%#llx\n" 996 "memlock:\t%llu\n" 997 "map_id:\t%u\n" 998 "frozen:\t%u\n", 999 map->map_type, 1000 map->key_size, 1001 map->value_size, 1002 map->max_entries, 1003 map->map_flags, 1004 (unsigned long long)map->map_extra, 1005 bpf_map_memory_usage(map), 1006 map->id, 1007 READ_ONCE(map->frozen)); 1008 if (type) { 1009 seq_printf(m, "owner_prog_type:\t%u\n", type); 1010 seq_printf(m, "owner_jited:\t%u\n", jited); 1011 } 1012 } 1013 #endif 1014 1015 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, 1016 loff_t *ppos) 1017 { 1018 /* We need this handler such that alloc_file() enables 1019 * f_mode with FMODE_CAN_READ. 1020 */ 1021 return -EINVAL; 1022 } 1023 1024 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, 1025 size_t siz, loff_t *ppos) 1026 { 1027 /* We need this handler such that alloc_file() enables 1028 * f_mode with FMODE_CAN_WRITE. 1029 */ 1030 return -EINVAL; 1031 } 1032 1033 /* called for any extra memory-mapped regions (except initial) */ 1034 static void bpf_map_mmap_open(struct vm_area_struct *vma) 1035 { 1036 struct bpf_map *map = vma->vm_file->private_data; 1037 1038 if (vma->vm_flags & VM_MAYWRITE) 1039 bpf_map_write_active_inc(map); 1040 } 1041 1042 /* called for all unmapped memory region (including initial) */ 1043 static void bpf_map_mmap_close(struct vm_area_struct *vma) 1044 { 1045 struct bpf_map *map = vma->vm_file->private_data; 1046 1047 if (vma->vm_flags & VM_MAYWRITE) 1048 bpf_map_write_active_dec(map); 1049 } 1050 1051 static const struct vm_operations_struct bpf_map_default_vmops = { 1052 .open = bpf_map_mmap_open, 1053 .close = bpf_map_mmap_close, 1054 }; 1055 1056 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) 1057 { 1058 struct bpf_map *map = filp->private_data; 1059 int err = 0; 1060 1061 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) 1062 return -ENOTSUPP; 1063 1064 if (!(vma->vm_flags & VM_SHARED)) 1065 return -EINVAL; 1066 1067 mutex_lock(&map->freeze_mutex); 1068 1069 if (vma->vm_flags & VM_WRITE) { 1070 if (map->frozen) { 1071 err = -EPERM; 1072 goto out; 1073 } 1074 /* map is meant to be read-only, so do not allow mapping as 1075 * writable, because it's possible to leak a writable page 1076 * reference and allows user-space to still modify it after 1077 * freezing, while verifier will assume contents do not change 1078 */ 1079 if (map->map_flags & BPF_F_RDONLY_PROG) { 1080 err = -EACCES; 1081 goto out; 1082 } 1083 bpf_map_write_active_inc(map); 1084 } 1085 out: 1086 mutex_unlock(&map->freeze_mutex); 1087 if (err) 1088 return err; 1089 1090 /* set default open/close callbacks */ 1091 vma->vm_ops = &bpf_map_default_vmops; 1092 vma->vm_private_data = map; 1093 vm_flags_clear(vma, VM_MAYEXEC); 1094 /* If mapping is read-only, then disallow potentially re-mapping with 1095 * PROT_WRITE by dropping VM_MAYWRITE flag. This VM_MAYWRITE clearing 1096 * means that as far as BPF map's memory-mapped VMAs are concerned, 1097 * VM_WRITE and VM_MAYWRITE and equivalent, if one of them is set, 1098 * both should be set, so we can forget about VM_MAYWRITE and always 1099 * check just VM_WRITE 1100 */ 1101 if (!(vma->vm_flags & VM_WRITE)) 1102 vm_flags_clear(vma, VM_MAYWRITE); 1103 1104 err = map->ops->map_mmap(map, vma); 1105 if (err) { 1106 if (vma->vm_flags & VM_WRITE) 1107 bpf_map_write_active_dec(map); 1108 } 1109 1110 return err; 1111 } 1112 1113 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) 1114 { 1115 struct bpf_map *map = filp->private_data; 1116 1117 if (map->ops->map_poll) 1118 return map->ops->map_poll(map, filp, pts); 1119 1120 return EPOLLERR; 1121 } 1122 1123 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, 1124 unsigned long len, unsigned long pgoff, 1125 unsigned long flags) 1126 { 1127 struct bpf_map *map = filp->private_data; 1128 1129 if (map->ops->map_get_unmapped_area) 1130 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); 1131 #ifdef CONFIG_MMU 1132 return mm_get_unmapped_area(current->mm, filp, addr, len, pgoff, flags); 1133 #else 1134 return addr; 1135 #endif 1136 } 1137 1138 const struct file_operations bpf_map_fops = { 1139 #ifdef CONFIG_PROC_FS 1140 .show_fdinfo = bpf_map_show_fdinfo, 1141 #endif 1142 .release = bpf_map_release, 1143 .read = bpf_dummy_read, 1144 .write = bpf_dummy_write, 1145 .mmap = bpf_map_mmap, 1146 .poll = bpf_map_poll, 1147 .get_unmapped_area = bpf_get_unmapped_area, 1148 }; 1149 1150 int bpf_map_new_fd(struct bpf_map *map, int flags) 1151 { 1152 int ret; 1153 1154 ret = security_bpf_map(map, OPEN_FMODE(flags)); 1155 if (ret < 0) 1156 return ret; 1157 1158 return anon_inode_getfd("bpf-map", &bpf_map_fops, map, 1159 flags | O_CLOEXEC); 1160 } 1161 1162 int bpf_get_file_flag(int flags) 1163 { 1164 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) 1165 return -EINVAL; 1166 if (flags & BPF_F_RDONLY) 1167 return O_RDONLY; 1168 if (flags & BPF_F_WRONLY) 1169 return O_WRONLY; 1170 return O_RDWR; 1171 } 1172 1173 /* helper macro to check that unused fields 'union bpf_attr' are zero */ 1174 #define CHECK_ATTR(CMD) \ 1175 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ 1176 sizeof(attr->CMD##_LAST_FIELD), 0, \ 1177 sizeof(*attr) - \ 1178 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ 1179 sizeof(attr->CMD##_LAST_FIELD)) != NULL 1180 1181 /* dst and src must have at least "size" number of bytes. 1182 * Return strlen on success and < 0 on error. 1183 */ 1184 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) 1185 { 1186 const char *end = src + size; 1187 const char *orig_src = src; 1188 1189 memset(dst, 0, size); 1190 /* Copy all isalnum(), '_' and '.' chars. */ 1191 while (src < end && *src) { 1192 if (!isalnum(*src) && 1193 *src != '_' && *src != '.') 1194 return -EINVAL; 1195 *dst++ = *src++; 1196 } 1197 1198 /* No '\0' found in "size" number of bytes */ 1199 if (src == end) 1200 return -EINVAL; 1201 1202 return src - orig_src; 1203 } 1204 1205 int map_check_no_btf(const struct bpf_map *map, 1206 const struct btf *btf, 1207 const struct btf_type *key_type, 1208 const struct btf_type *value_type) 1209 { 1210 return -ENOTSUPP; 1211 } 1212 1213 static int map_check_btf(struct bpf_map *map, struct bpf_token *token, 1214 const struct btf *btf, u32 btf_key_id, u32 btf_value_id) 1215 { 1216 const struct btf_type *key_type, *value_type; 1217 u32 key_size, value_size; 1218 int ret = 0; 1219 1220 /* Some maps allow key to be unspecified. */ 1221 if (btf_key_id) { 1222 key_type = btf_type_id_size(btf, &btf_key_id, &key_size); 1223 if (!key_type || key_size != map->key_size) 1224 return -EINVAL; 1225 } else { 1226 key_type = btf_type_by_id(btf, 0); 1227 if (!map->ops->map_check_btf) 1228 return -EINVAL; 1229 } 1230 1231 value_type = btf_type_id_size(btf, &btf_value_id, &value_size); 1232 if (!value_type || value_size != map->value_size) 1233 return -EINVAL; 1234 1235 map->record = btf_parse_fields(btf, value_type, 1236 BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | 1237 BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR, 1238 map->value_size); 1239 if (!IS_ERR_OR_NULL(map->record)) { 1240 int i; 1241 1242 if (!bpf_token_capable(token, CAP_BPF)) { 1243 ret = -EPERM; 1244 goto free_map_tab; 1245 } 1246 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { 1247 ret = -EACCES; 1248 goto free_map_tab; 1249 } 1250 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { 1251 switch (map->record->field_mask & (1 << i)) { 1252 case 0: 1253 continue; 1254 case BPF_SPIN_LOCK: 1255 case BPF_RES_SPIN_LOCK: 1256 if (map->map_type != BPF_MAP_TYPE_HASH && 1257 map->map_type != BPF_MAP_TYPE_ARRAY && 1258 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && 1259 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1260 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1261 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1262 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1263 ret = -EOPNOTSUPP; 1264 goto free_map_tab; 1265 } 1266 break; 1267 case BPF_TIMER: 1268 case BPF_WORKQUEUE: 1269 if (map->map_type != BPF_MAP_TYPE_HASH && 1270 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1271 map->map_type != BPF_MAP_TYPE_ARRAY) { 1272 ret = -EOPNOTSUPP; 1273 goto free_map_tab; 1274 } 1275 break; 1276 case BPF_KPTR_UNREF: 1277 case BPF_KPTR_REF: 1278 case BPF_KPTR_PERCPU: 1279 case BPF_REFCOUNT: 1280 if (map->map_type != BPF_MAP_TYPE_HASH && 1281 map->map_type != BPF_MAP_TYPE_PERCPU_HASH && 1282 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1283 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && 1284 map->map_type != BPF_MAP_TYPE_ARRAY && 1285 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && 1286 map->map_type != BPF_MAP_TYPE_SK_STORAGE && 1287 map->map_type != BPF_MAP_TYPE_INODE_STORAGE && 1288 map->map_type != BPF_MAP_TYPE_TASK_STORAGE && 1289 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { 1290 ret = -EOPNOTSUPP; 1291 goto free_map_tab; 1292 } 1293 break; 1294 case BPF_UPTR: 1295 if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) { 1296 ret = -EOPNOTSUPP; 1297 goto free_map_tab; 1298 } 1299 break; 1300 case BPF_LIST_HEAD: 1301 case BPF_RB_ROOT: 1302 if (map->map_type != BPF_MAP_TYPE_HASH && 1303 map->map_type != BPF_MAP_TYPE_LRU_HASH && 1304 map->map_type != BPF_MAP_TYPE_ARRAY) { 1305 ret = -EOPNOTSUPP; 1306 goto free_map_tab; 1307 } 1308 break; 1309 default: 1310 /* Fail if map_type checks are missing for a field type */ 1311 ret = -EOPNOTSUPP; 1312 goto free_map_tab; 1313 } 1314 } 1315 } 1316 1317 ret = btf_check_and_fixup_fields(btf, map->record); 1318 if (ret < 0) 1319 goto free_map_tab; 1320 1321 if (map->ops->map_check_btf) { 1322 ret = map->ops->map_check_btf(map, btf, key_type, value_type); 1323 if (ret < 0) 1324 goto free_map_tab; 1325 } 1326 1327 return ret; 1328 free_map_tab: 1329 bpf_map_free_record(map); 1330 return ret; 1331 } 1332 1333 static bool bpf_net_capable(void) 1334 { 1335 return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN); 1336 } 1337 1338 #define BPF_MAP_CREATE_LAST_FIELD map_token_fd 1339 /* called via syscall */ 1340 static int map_create(union bpf_attr *attr, bool kernel) 1341 { 1342 const struct bpf_map_ops *ops; 1343 struct bpf_token *token = NULL; 1344 int numa_node = bpf_map_attr_numa_node(attr); 1345 u32 map_type = attr->map_type; 1346 struct bpf_map *map; 1347 bool token_flag; 1348 int f_flags; 1349 int err; 1350 1351 err = CHECK_ATTR(BPF_MAP_CREATE); 1352 if (err) 1353 return -EINVAL; 1354 1355 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it 1356 * to avoid per-map type checks tripping on unknown flag 1357 */ 1358 token_flag = attr->map_flags & BPF_F_TOKEN_FD; 1359 attr->map_flags &= ~BPF_F_TOKEN_FD; 1360 1361 if (attr->btf_vmlinux_value_type_id) { 1362 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || 1363 attr->btf_key_type_id || attr->btf_value_type_id) 1364 return -EINVAL; 1365 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { 1366 return -EINVAL; 1367 } 1368 1369 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && 1370 attr->map_type != BPF_MAP_TYPE_ARENA && 1371 attr->map_extra != 0) 1372 return -EINVAL; 1373 1374 f_flags = bpf_get_file_flag(attr->map_flags); 1375 if (f_flags < 0) 1376 return f_flags; 1377 1378 if (numa_node != NUMA_NO_NODE && 1379 ((unsigned int)numa_node >= nr_node_ids || 1380 !node_online(numa_node))) 1381 return -EINVAL; 1382 1383 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ 1384 map_type = attr->map_type; 1385 if (map_type >= ARRAY_SIZE(bpf_map_types)) 1386 return -EINVAL; 1387 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); 1388 ops = bpf_map_types[map_type]; 1389 if (!ops) 1390 return -EINVAL; 1391 1392 if (ops->map_alloc_check) { 1393 err = ops->map_alloc_check(attr); 1394 if (err) 1395 return err; 1396 } 1397 if (attr->map_ifindex) 1398 ops = &bpf_map_offload_ops; 1399 if (!ops->map_mem_usage) 1400 return -EINVAL; 1401 1402 if (token_flag) { 1403 token = bpf_token_get_from_fd(attr->map_token_fd); 1404 if (IS_ERR(token)) 1405 return PTR_ERR(token); 1406 1407 /* if current token doesn't grant map creation permissions, 1408 * then we can't use this token, so ignore it and rely on 1409 * system-wide capabilities checks 1410 */ 1411 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || 1412 !bpf_token_allow_map_type(token, attr->map_type)) { 1413 bpf_token_put(token); 1414 token = NULL; 1415 } 1416 } 1417 1418 err = -EPERM; 1419 1420 /* Intent here is for unprivileged_bpf_disabled to block BPF map 1421 * creation for unprivileged users; other actions depend 1422 * on fd availability and access to bpffs, so are dependent on 1423 * object creation success. Even with unprivileged BPF disabled, 1424 * capability checks are still carried out. 1425 */ 1426 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) 1427 goto put_token; 1428 1429 /* check privileged map type permissions */ 1430 switch (map_type) { 1431 case BPF_MAP_TYPE_ARRAY: 1432 case BPF_MAP_TYPE_PERCPU_ARRAY: 1433 case BPF_MAP_TYPE_PROG_ARRAY: 1434 case BPF_MAP_TYPE_PERF_EVENT_ARRAY: 1435 case BPF_MAP_TYPE_CGROUP_ARRAY: 1436 case BPF_MAP_TYPE_ARRAY_OF_MAPS: 1437 case BPF_MAP_TYPE_HASH: 1438 case BPF_MAP_TYPE_PERCPU_HASH: 1439 case BPF_MAP_TYPE_HASH_OF_MAPS: 1440 case BPF_MAP_TYPE_RINGBUF: 1441 case BPF_MAP_TYPE_USER_RINGBUF: 1442 case BPF_MAP_TYPE_CGROUP_STORAGE: 1443 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: 1444 /* unprivileged */ 1445 break; 1446 case BPF_MAP_TYPE_SK_STORAGE: 1447 case BPF_MAP_TYPE_INODE_STORAGE: 1448 case BPF_MAP_TYPE_TASK_STORAGE: 1449 case BPF_MAP_TYPE_CGRP_STORAGE: 1450 case BPF_MAP_TYPE_BLOOM_FILTER: 1451 case BPF_MAP_TYPE_LPM_TRIE: 1452 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: 1453 case BPF_MAP_TYPE_STACK_TRACE: 1454 case BPF_MAP_TYPE_QUEUE: 1455 case BPF_MAP_TYPE_STACK: 1456 case BPF_MAP_TYPE_LRU_HASH: 1457 case BPF_MAP_TYPE_LRU_PERCPU_HASH: 1458 case BPF_MAP_TYPE_STRUCT_OPS: 1459 case BPF_MAP_TYPE_CPUMAP: 1460 case BPF_MAP_TYPE_ARENA: 1461 if (!bpf_token_capable(token, CAP_BPF)) 1462 goto put_token; 1463 break; 1464 case BPF_MAP_TYPE_SOCKMAP: 1465 case BPF_MAP_TYPE_SOCKHASH: 1466 case BPF_MAP_TYPE_DEVMAP: 1467 case BPF_MAP_TYPE_DEVMAP_HASH: 1468 case BPF_MAP_TYPE_XSKMAP: 1469 if (!bpf_token_capable(token, CAP_NET_ADMIN)) 1470 goto put_token; 1471 break; 1472 default: 1473 WARN(1, "unsupported map type %d", map_type); 1474 goto put_token; 1475 } 1476 1477 map = ops->map_alloc(attr); 1478 if (IS_ERR(map)) { 1479 err = PTR_ERR(map); 1480 goto put_token; 1481 } 1482 map->ops = ops; 1483 map->map_type = map_type; 1484 1485 err = bpf_obj_name_cpy(map->name, attr->map_name, 1486 sizeof(attr->map_name)); 1487 if (err < 0) 1488 goto free_map; 1489 1490 atomic64_set(&map->refcnt, 1); 1491 atomic64_set(&map->usercnt, 1); 1492 mutex_init(&map->freeze_mutex); 1493 spin_lock_init(&map->owner.lock); 1494 1495 if (attr->btf_key_type_id || attr->btf_value_type_id || 1496 /* Even the map's value is a kernel's struct, 1497 * the bpf_prog.o must have BTF to begin with 1498 * to figure out the corresponding kernel's 1499 * counter part. Thus, attr->btf_fd has 1500 * to be valid also. 1501 */ 1502 attr->btf_vmlinux_value_type_id) { 1503 struct btf *btf; 1504 1505 btf = btf_get_by_fd(attr->btf_fd); 1506 if (IS_ERR(btf)) { 1507 err = PTR_ERR(btf); 1508 goto free_map; 1509 } 1510 if (btf_is_kernel(btf)) { 1511 btf_put(btf); 1512 err = -EACCES; 1513 goto free_map; 1514 } 1515 map->btf = btf; 1516 1517 if (attr->btf_value_type_id) { 1518 err = map_check_btf(map, token, btf, attr->btf_key_type_id, 1519 attr->btf_value_type_id); 1520 if (err) 1521 goto free_map; 1522 } 1523 1524 map->btf_key_type_id = attr->btf_key_type_id; 1525 map->btf_value_type_id = attr->btf_value_type_id; 1526 map->btf_vmlinux_value_type_id = 1527 attr->btf_vmlinux_value_type_id; 1528 } 1529 1530 err = security_bpf_map_create(map, attr, token, kernel); 1531 if (err) 1532 goto free_map_sec; 1533 1534 err = bpf_map_alloc_id(map); 1535 if (err) 1536 goto free_map_sec; 1537 1538 bpf_map_save_memcg(map); 1539 bpf_token_put(token); 1540 1541 err = bpf_map_new_fd(map, f_flags); 1542 if (err < 0) { 1543 /* failed to allocate fd. 1544 * bpf_map_put_with_uref() is needed because the above 1545 * bpf_map_alloc_id() has published the map 1546 * to the userspace and the userspace may 1547 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. 1548 */ 1549 bpf_map_put_with_uref(map); 1550 return err; 1551 } 1552 1553 return err; 1554 1555 free_map_sec: 1556 security_bpf_map_free(map); 1557 free_map: 1558 bpf_map_free(map); 1559 put_token: 1560 bpf_token_put(token); 1561 return err; 1562 } 1563 1564 void bpf_map_inc(struct bpf_map *map) 1565 { 1566 atomic64_inc(&map->refcnt); 1567 } 1568 EXPORT_SYMBOL_GPL(bpf_map_inc); 1569 1570 void bpf_map_inc_with_uref(struct bpf_map *map) 1571 { 1572 atomic64_inc(&map->refcnt); 1573 atomic64_inc(&map->usercnt); 1574 } 1575 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); 1576 1577 struct bpf_map *bpf_map_get(u32 ufd) 1578 { 1579 CLASS(fd, f)(ufd); 1580 struct bpf_map *map = __bpf_map_get(f); 1581 1582 if (!IS_ERR(map)) 1583 bpf_map_inc(map); 1584 1585 return map; 1586 } 1587 EXPORT_SYMBOL_NS(bpf_map_get, "BPF_INTERNAL"); 1588 1589 struct bpf_map *bpf_map_get_with_uref(u32 ufd) 1590 { 1591 CLASS(fd, f)(ufd); 1592 struct bpf_map *map = __bpf_map_get(f); 1593 1594 if (!IS_ERR(map)) 1595 bpf_map_inc_with_uref(map); 1596 1597 return map; 1598 } 1599 1600 /* map_idr_lock should have been held or the map should have been 1601 * protected by rcu read lock. 1602 */ 1603 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) 1604 { 1605 int refold; 1606 1607 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); 1608 if (!refold) 1609 return ERR_PTR(-ENOENT); 1610 if (uref) 1611 atomic64_inc(&map->usercnt); 1612 1613 return map; 1614 } 1615 1616 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) 1617 { 1618 lockdep_assert(rcu_read_lock_held()); 1619 return __bpf_map_inc_not_zero(map, false); 1620 } 1621 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); 1622 1623 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) 1624 { 1625 return -ENOTSUPP; 1626 } 1627 1628 static void *__bpf_copy_key(void __user *ukey, u64 key_size) 1629 { 1630 if (key_size) 1631 return vmemdup_user(ukey, key_size); 1632 1633 if (ukey) 1634 return ERR_PTR(-EINVAL); 1635 1636 return NULL; 1637 } 1638 1639 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) 1640 { 1641 if (key_size) 1642 return kvmemdup_bpfptr(ukey, key_size); 1643 1644 if (!bpfptr_is_null(ukey)) 1645 return ERR_PTR(-EINVAL); 1646 1647 return NULL; 1648 } 1649 1650 /* last field in 'union bpf_attr' used by this command */ 1651 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags 1652 1653 static int map_lookup_elem(union bpf_attr *attr) 1654 { 1655 void __user *ukey = u64_to_user_ptr(attr->key); 1656 void __user *uvalue = u64_to_user_ptr(attr->value); 1657 struct bpf_map *map; 1658 void *key, *value; 1659 u32 value_size; 1660 int err; 1661 1662 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) 1663 return -EINVAL; 1664 1665 if (attr->flags & ~BPF_F_LOCK) 1666 return -EINVAL; 1667 1668 CLASS(fd, f)(attr->map_fd); 1669 map = __bpf_map_get(f); 1670 if (IS_ERR(map)) 1671 return PTR_ERR(map); 1672 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1673 return -EPERM; 1674 1675 if ((attr->flags & BPF_F_LOCK) && 1676 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) 1677 return -EINVAL; 1678 1679 key = __bpf_copy_key(ukey, map->key_size); 1680 if (IS_ERR(key)) 1681 return PTR_ERR(key); 1682 1683 value_size = bpf_map_value_size(map); 1684 1685 err = -ENOMEM; 1686 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1687 if (!value) 1688 goto free_key; 1689 1690 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { 1691 if (copy_from_user(value, uvalue, value_size)) 1692 err = -EFAULT; 1693 else 1694 err = bpf_map_copy_value(map, key, value, attr->flags); 1695 goto free_value; 1696 } 1697 1698 err = bpf_map_copy_value(map, key, value, attr->flags); 1699 if (err) 1700 goto free_value; 1701 1702 err = -EFAULT; 1703 if (copy_to_user(uvalue, value, value_size) != 0) 1704 goto free_value; 1705 1706 err = 0; 1707 1708 free_value: 1709 kvfree(value); 1710 free_key: 1711 kvfree(key); 1712 return err; 1713 } 1714 1715 1716 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags 1717 1718 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) 1719 { 1720 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1721 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); 1722 struct bpf_map *map; 1723 void *key, *value; 1724 u32 value_size; 1725 int err; 1726 1727 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) 1728 return -EINVAL; 1729 1730 CLASS(fd, f)(attr->map_fd); 1731 map = __bpf_map_get(f); 1732 if (IS_ERR(map)) 1733 return PTR_ERR(map); 1734 bpf_map_write_active_inc(map); 1735 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1736 err = -EPERM; 1737 goto err_put; 1738 } 1739 1740 if ((attr->flags & BPF_F_LOCK) && 1741 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1742 err = -EINVAL; 1743 goto err_put; 1744 } 1745 1746 key = ___bpf_copy_key(ukey, map->key_size); 1747 if (IS_ERR(key)) { 1748 err = PTR_ERR(key); 1749 goto err_put; 1750 } 1751 1752 value_size = bpf_map_value_size(map); 1753 value = kvmemdup_bpfptr(uvalue, value_size); 1754 if (IS_ERR(value)) { 1755 err = PTR_ERR(value); 1756 goto free_key; 1757 } 1758 1759 err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags); 1760 if (!err) 1761 maybe_wait_bpf_programs(map); 1762 1763 kvfree(value); 1764 free_key: 1765 kvfree(key); 1766 err_put: 1767 bpf_map_write_active_dec(map); 1768 return err; 1769 } 1770 1771 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key 1772 1773 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) 1774 { 1775 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); 1776 struct bpf_map *map; 1777 void *key; 1778 int err; 1779 1780 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) 1781 return -EINVAL; 1782 1783 CLASS(fd, f)(attr->map_fd); 1784 map = __bpf_map_get(f); 1785 if (IS_ERR(map)) 1786 return PTR_ERR(map); 1787 bpf_map_write_active_inc(map); 1788 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 1789 err = -EPERM; 1790 goto err_put; 1791 } 1792 1793 key = ___bpf_copy_key(ukey, map->key_size); 1794 if (IS_ERR(key)) { 1795 err = PTR_ERR(key); 1796 goto err_put; 1797 } 1798 1799 if (bpf_map_is_offloaded(map)) { 1800 err = bpf_map_offload_delete_elem(map, key); 1801 goto out; 1802 } else if (IS_FD_PROG_ARRAY(map) || 1803 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { 1804 /* These maps require sleepable context */ 1805 err = map->ops->map_delete_elem(map, key); 1806 goto out; 1807 } 1808 1809 bpf_disable_instrumentation(); 1810 rcu_read_lock(); 1811 err = map->ops->map_delete_elem(map, key); 1812 rcu_read_unlock(); 1813 bpf_enable_instrumentation(); 1814 if (!err) 1815 maybe_wait_bpf_programs(map); 1816 out: 1817 kvfree(key); 1818 err_put: 1819 bpf_map_write_active_dec(map); 1820 return err; 1821 } 1822 1823 /* last field in 'union bpf_attr' used by this command */ 1824 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key 1825 1826 static int map_get_next_key(union bpf_attr *attr) 1827 { 1828 void __user *ukey = u64_to_user_ptr(attr->key); 1829 void __user *unext_key = u64_to_user_ptr(attr->next_key); 1830 struct bpf_map *map; 1831 void *key, *next_key; 1832 int err; 1833 1834 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) 1835 return -EINVAL; 1836 1837 CLASS(fd, f)(attr->map_fd); 1838 map = __bpf_map_get(f); 1839 if (IS_ERR(map)) 1840 return PTR_ERR(map); 1841 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) 1842 return -EPERM; 1843 1844 if (ukey) { 1845 key = __bpf_copy_key(ukey, map->key_size); 1846 if (IS_ERR(key)) 1847 return PTR_ERR(key); 1848 } else { 1849 key = NULL; 1850 } 1851 1852 err = -ENOMEM; 1853 next_key = kvmalloc(map->key_size, GFP_USER); 1854 if (!next_key) 1855 goto free_key; 1856 1857 if (bpf_map_is_offloaded(map)) { 1858 err = bpf_map_offload_get_next_key(map, key, next_key); 1859 goto out; 1860 } 1861 1862 rcu_read_lock(); 1863 err = map->ops->map_get_next_key(map, key, next_key); 1864 rcu_read_unlock(); 1865 out: 1866 if (err) 1867 goto free_next_key; 1868 1869 err = -EFAULT; 1870 if (copy_to_user(unext_key, next_key, map->key_size) != 0) 1871 goto free_next_key; 1872 1873 err = 0; 1874 1875 free_next_key: 1876 kvfree(next_key); 1877 free_key: 1878 kvfree(key); 1879 return err; 1880 } 1881 1882 int generic_map_delete_batch(struct bpf_map *map, 1883 const union bpf_attr *attr, 1884 union bpf_attr __user *uattr) 1885 { 1886 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1887 u32 cp, max_count; 1888 int err = 0; 1889 void *key; 1890 1891 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1892 return -EINVAL; 1893 1894 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1895 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1896 return -EINVAL; 1897 } 1898 1899 max_count = attr->batch.count; 1900 if (!max_count) 1901 return 0; 1902 1903 if (put_user(0, &uattr->batch.count)) 1904 return -EFAULT; 1905 1906 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1907 if (!key) 1908 return -ENOMEM; 1909 1910 for (cp = 0; cp < max_count; cp++) { 1911 err = -EFAULT; 1912 if (copy_from_user(key, keys + cp * map->key_size, 1913 map->key_size)) 1914 break; 1915 1916 if (bpf_map_is_offloaded(map)) { 1917 err = bpf_map_offload_delete_elem(map, key); 1918 break; 1919 } 1920 1921 bpf_disable_instrumentation(); 1922 rcu_read_lock(); 1923 err = map->ops->map_delete_elem(map, key); 1924 rcu_read_unlock(); 1925 bpf_enable_instrumentation(); 1926 if (err) 1927 break; 1928 cond_resched(); 1929 } 1930 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1931 err = -EFAULT; 1932 1933 kvfree(key); 1934 1935 return err; 1936 } 1937 1938 int generic_map_update_batch(struct bpf_map *map, struct file *map_file, 1939 const union bpf_attr *attr, 1940 union bpf_attr __user *uattr) 1941 { 1942 void __user *values = u64_to_user_ptr(attr->batch.values); 1943 void __user *keys = u64_to_user_ptr(attr->batch.keys); 1944 u32 value_size, cp, max_count; 1945 void *key, *value; 1946 int err = 0; 1947 1948 if (attr->batch.elem_flags & ~BPF_F_LOCK) 1949 return -EINVAL; 1950 1951 if ((attr->batch.elem_flags & BPF_F_LOCK) && 1952 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 1953 return -EINVAL; 1954 } 1955 1956 value_size = bpf_map_value_size(map); 1957 1958 max_count = attr->batch.count; 1959 if (!max_count) 1960 return 0; 1961 1962 if (put_user(0, &uattr->batch.count)) 1963 return -EFAULT; 1964 1965 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 1966 if (!key) 1967 return -ENOMEM; 1968 1969 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 1970 if (!value) { 1971 kvfree(key); 1972 return -ENOMEM; 1973 } 1974 1975 for (cp = 0; cp < max_count; cp++) { 1976 err = -EFAULT; 1977 if (copy_from_user(key, keys + cp * map->key_size, 1978 map->key_size) || 1979 copy_from_user(value, values + cp * value_size, value_size)) 1980 break; 1981 1982 err = bpf_map_update_value(map, map_file, key, value, 1983 attr->batch.elem_flags); 1984 1985 if (err) 1986 break; 1987 cond_resched(); 1988 } 1989 1990 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) 1991 err = -EFAULT; 1992 1993 kvfree(value); 1994 kvfree(key); 1995 1996 return err; 1997 } 1998 1999 int generic_map_lookup_batch(struct bpf_map *map, 2000 const union bpf_attr *attr, 2001 union bpf_attr __user *uattr) 2002 { 2003 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); 2004 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); 2005 void __user *values = u64_to_user_ptr(attr->batch.values); 2006 void __user *keys = u64_to_user_ptr(attr->batch.keys); 2007 void *buf, *buf_prevkey, *prev_key, *key, *value; 2008 u32 value_size, cp, max_count; 2009 int err; 2010 2011 if (attr->batch.elem_flags & ~BPF_F_LOCK) 2012 return -EINVAL; 2013 2014 if ((attr->batch.elem_flags & BPF_F_LOCK) && 2015 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) 2016 return -EINVAL; 2017 2018 value_size = bpf_map_value_size(map); 2019 2020 max_count = attr->batch.count; 2021 if (!max_count) 2022 return 0; 2023 2024 if (put_user(0, &uattr->batch.count)) 2025 return -EFAULT; 2026 2027 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); 2028 if (!buf_prevkey) 2029 return -ENOMEM; 2030 2031 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); 2032 if (!buf) { 2033 kvfree(buf_prevkey); 2034 return -ENOMEM; 2035 } 2036 2037 err = -EFAULT; 2038 prev_key = NULL; 2039 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) 2040 goto free_buf; 2041 key = buf; 2042 value = key + map->key_size; 2043 if (ubatch) 2044 prev_key = buf_prevkey; 2045 2046 for (cp = 0; cp < max_count;) { 2047 rcu_read_lock(); 2048 err = map->ops->map_get_next_key(map, prev_key, key); 2049 rcu_read_unlock(); 2050 if (err) 2051 break; 2052 err = bpf_map_copy_value(map, key, value, 2053 attr->batch.elem_flags); 2054 2055 if (err == -ENOENT) 2056 goto next_key; 2057 2058 if (err) 2059 goto free_buf; 2060 2061 if (copy_to_user(keys + cp * map->key_size, key, 2062 map->key_size)) { 2063 err = -EFAULT; 2064 goto free_buf; 2065 } 2066 if (copy_to_user(values + cp * value_size, value, value_size)) { 2067 err = -EFAULT; 2068 goto free_buf; 2069 } 2070 2071 cp++; 2072 next_key: 2073 if (!prev_key) 2074 prev_key = buf_prevkey; 2075 2076 swap(prev_key, key); 2077 cond_resched(); 2078 } 2079 2080 if (err == -EFAULT) 2081 goto free_buf; 2082 2083 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || 2084 (cp && copy_to_user(uobatch, prev_key, map->key_size)))) 2085 err = -EFAULT; 2086 2087 free_buf: 2088 kvfree(buf_prevkey); 2089 kvfree(buf); 2090 return err; 2091 } 2092 2093 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags 2094 2095 static int map_lookup_and_delete_elem(union bpf_attr *attr) 2096 { 2097 void __user *ukey = u64_to_user_ptr(attr->key); 2098 void __user *uvalue = u64_to_user_ptr(attr->value); 2099 struct bpf_map *map; 2100 void *key, *value; 2101 u32 value_size; 2102 int err; 2103 2104 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) 2105 return -EINVAL; 2106 2107 if (attr->flags & ~BPF_F_LOCK) 2108 return -EINVAL; 2109 2110 CLASS(fd, f)(attr->map_fd); 2111 map = __bpf_map_get(f); 2112 if (IS_ERR(map)) 2113 return PTR_ERR(map); 2114 bpf_map_write_active_inc(map); 2115 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || 2116 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 2117 err = -EPERM; 2118 goto err_put; 2119 } 2120 2121 if (attr->flags && 2122 (map->map_type == BPF_MAP_TYPE_QUEUE || 2123 map->map_type == BPF_MAP_TYPE_STACK)) { 2124 err = -EINVAL; 2125 goto err_put; 2126 } 2127 2128 if ((attr->flags & BPF_F_LOCK) && 2129 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { 2130 err = -EINVAL; 2131 goto err_put; 2132 } 2133 2134 key = __bpf_copy_key(ukey, map->key_size); 2135 if (IS_ERR(key)) { 2136 err = PTR_ERR(key); 2137 goto err_put; 2138 } 2139 2140 value_size = bpf_map_value_size(map); 2141 2142 err = -ENOMEM; 2143 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); 2144 if (!value) 2145 goto free_key; 2146 2147 err = -ENOTSUPP; 2148 if (map->map_type == BPF_MAP_TYPE_QUEUE || 2149 map->map_type == BPF_MAP_TYPE_STACK) { 2150 err = map->ops->map_pop_elem(map, value); 2151 } else if (map->map_type == BPF_MAP_TYPE_HASH || 2152 map->map_type == BPF_MAP_TYPE_PERCPU_HASH || 2153 map->map_type == BPF_MAP_TYPE_LRU_HASH || 2154 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { 2155 if (!bpf_map_is_offloaded(map)) { 2156 bpf_disable_instrumentation(); 2157 rcu_read_lock(); 2158 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); 2159 rcu_read_unlock(); 2160 bpf_enable_instrumentation(); 2161 } 2162 } 2163 2164 if (err) 2165 goto free_value; 2166 2167 if (copy_to_user(uvalue, value, value_size) != 0) { 2168 err = -EFAULT; 2169 goto free_value; 2170 } 2171 2172 err = 0; 2173 2174 free_value: 2175 kvfree(value); 2176 free_key: 2177 kvfree(key); 2178 err_put: 2179 bpf_map_write_active_dec(map); 2180 return err; 2181 } 2182 2183 #define BPF_MAP_FREEZE_LAST_FIELD map_fd 2184 2185 static int map_freeze(const union bpf_attr *attr) 2186 { 2187 int err = 0; 2188 struct bpf_map *map; 2189 2190 if (CHECK_ATTR(BPF_MAP_FREEZE)) 2191 return -EINVAL; 2192 2193 CLASS(fd, f)(attr->map_fd); 2194 map = __bpf_map_get(f); 2195 if (IS_ERR(map)) 2196 return PTR_ERR(map); 2197 2198 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) 2199 return -ENOTSUPP; 2200 2201 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) 2202 return -EPERM; 2203 2204 mutex_lock(&map->freeze_mutex); 2205 if (bpf_map_write_active(map)) { 2206 err = -EBUSY; 2207 goto err_put; 2208 } 2209 if (READ_ONCE(map->frozen)) { 2210 err = -EBUSY; 2211 goto err_put; 2212 } 2213 2214 WRITE_ONCE(map->frozen, true); 2215 err_put: 2216 mutex_unlock(&map->freeze_mutex); 2217 return err; 2218 } 2219 2220 static const struct bpf_prog_ops * const bpf_prog_types[] = { 2221 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ 2222 [_id] = & _name ## _prog_ops, 2223 #define BPF_MAP_TYPE(_id, _ops) 2224 #define BPF_LINK_TYPE(_id, _name) 2225 #include <linux/bpf_types.h> 2226 #undef BPF_PROG_TYPE 2227 #undef BPF_MAP_TYPE 2228 #undef BPF_LINK_TYPE 2229 }; 2230 2231 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) 2232 { 2233 const struct bpf_prog_ops *ops; 2234 2235 if (type >= ARRAY_SIZE(bpf_prog_types)) 2236 return -EINVAL; 2237 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); 2238 ops = bpf_prog_types[type]; 2239 if (!ops) 2240 return -EINVAL; 2241 2242 if (!bpf_prog_is_offloaded(prog->aux)) 2243 prog->aux->ops = ops; 2244 else 2245 prog->aux->ops = &bpf_offload_prog_ops; 2246 prog->type = type; 2247 return 0; 2248 } 2249 2250 enum bpf_audit { 2251 BPF_AUDIT_LOAD, 2252 BPF_AUDIT_UNLOAD, 2253 BPF_AUDIT_MAX, 2254 }; 2255 2256 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { 2257 [BPF_AUDIT_LOAD] = "LOAD", 2258 [BPF_AUDIT_UNLOAD] = "UNLOAD", 2259 }; 2260 2261 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) 2262 { 2263 struct audit_context *ctx = NULL; 2264 struct audit_buffer *ab; 2265 2266 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) 2267 return; 2268 if (audit_enabled == AUDIT_OFF) 2269 return; 2270 if (!in_irq() && !irqs_disabled()) 2271 ctx = audit_context(); 2272 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); 2273 if (unlikely(!ab)) 2274 return; 2275 audit_log_format(ab, "prog-id=%u op=%s", 2276 prog->aux->id, bpf_audit_str[op]); 2277 audit_log_end(ab); 2278 } 2279 2280 static int bpf_prog_alloc_id(struct bpf_prog *prog) 2281 { 2282 int id; 2283 2284 idr_preload(GFP_KERNEL); 2285 spin_lock_bh(&prog_idr_lock); 2286 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); 2287 if (id > 0) 2288 prog->aux->id = id; 2289 spin_unlock_bh(&prog_idr_lock); 2290 idr_preload_end(); 2291 2292 /* id is in [1, INT_MAX) */ 2293 if (WARN_ON_ONCE(!id)) 2294 return -ENOSPC; 2295 2296 return id > 0 ? 0 : id; 2297 } 2298 2299 void bpf_prog_free_id(struct bpf_prog *prog) 2300 { 2301 unsigned long flags; 2302 2303 /* cBPF to eBPF migrations are currently not in the idr store. 2304 * Offloaded programs are removed from the store when their device 2305 * disappears - even if someone grabs an fd to them they are unusable, 2306 * simply waiting for refcnt to drop to be freed. 2307 */ 2308 if (!prog->aux->id) 2309 return; 2310 2311 spin_lock_irqsave(&prog_idr_lock, flags); 2312 idr_remove(&prog_idr, prog->aux->id); 2313 prog->aux->id = 0; 2314 spin_unlock_irqrestore(&prog_idr_lock, flags); 2315 } 2316 2317 static void __bpf_prog_put_rcu(struct rcu_head *rcu) 2318 { 2319 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); 2320 2321 kvfree(aux->func_info); 2322 kfree(aux->func_info_aux); 2323 free_uid(aux->user); 2324 security_bpf_prog_free(aux->prog); 2325 bpf_prog_free(aux->prog); 2326 } 2327 2328 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) 2329 { 2330 bpf_prog_kallsyms_del_all(prog); 2331 btf_put(prog->aux->btf); 2332 module_put(prog->aux->mod); 2333 kvfree(prog->aux->jited_linfo); 2334 kvfree(prog->aux->linfo); 2335 kfree(prog->aux->kfunc_tab); 2336 kfree(prog->aux->ctx_arg_info); 2337 if (prog->aux->attach_btf) 2338 btf_put(prog->aux->attach_btf); 2339 2340 if (deferred) { 2341 if (prog->sleepable) 2342 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); 2343 else 2344 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); 2345 } else { 2346 __bpf_prog_put_rcu(&prog->aux->rcu); 2347 } 2348 } 2349 2350 static void bpf_prog_put_deferred(struct work_struct *work) 2351 { 2352 struct bpf_prog_aux *aux; 2353 struct bpf_prog *prog; 2354 2355 aux = container_of(work, struct bpf_prog_aux, work); 2356 prog = aux->prog; 2357 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); 2358 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); 2359 bpf_prog_free_id(prog); 2360 __bpf_prog_put_noref(prog, true); 2361 } 2362 2363 static void __bpf_prog_put(struct bpf_prog *prog) 2364 { 2365 struct bpf_prog_aux *aux = prog->aux; 2366 2367 if (atomic64_dec_and_test(&aux->refcnt)) { 2368 if (in_irq() || irqs_disabled()) { 2369 INIT_WORK(&aux->work, bpf_prog_put_deferred); 2370 schedule_work(&aux->work); 2371 } else { 2372 bpf_prog_put_deferred(&aux->work); 2373 } 2374 } 2375 } 2376 2377 void bpf_prog_put(struct bpf_prog *prog) 2378 { 2379 __bpf_prog_put(prog); 2380 } 2381 EXPORT_SYMBOL_GPL(bpf_prog_put); 2382 2383 static int bpf_prog_release(struct inode *inode, struct file *filp) 2384 { 2385 struct bpf_prog *prog = filp->private_data; 2386 2387 bpf_prog_put(prog); 2388 return 0; 2389 } 2390 2391 struct bpf_prog_kstats { 2392 u64 nsecs; 2393 u64 cnt; 2394 u64 misses; 2395 }; 2396 2397 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) 2398 { 2399 struct bpf_prog_stats *stats; 2400 unsigned int flags; 2401 2402 stats = this_cpu_ptr(prog->stats); 2403 flags = u64_stats_update_begin_irqsave(&stats->syncp); 2404 u64_stats_inc(&stats->misses); 2405 u64_stats_update_end_irqrestore(&stats->syncp, flags); 2406 } 2407 2408 static void bpf_prog_get_stats(const struct bpf_prog *prog, 2409 struct bpf_prog_kstats *stats) 2410 { 2411 u64 nsecs = 0, cnt = 0, misses = 0; 2412 int cpu; 2413 2414 for_each_possible_cpu(cpu) { 2415 const struct bpf_prog_stats *st; 2416 unsigned int start; 2417 u64 tnsecs, tcnt, tmisses; 2418 2419 st = per_cpu_ptr(prog->stats, cpu); 2420 do { 2421 start = u64_stats_fetch_begin(&st->syncp); 2422 tnsecs = u64_stats_read(&st->nsecs); 2423 tcnt = u64_stats_read(&st->cnt); 2424 tmisses = u64_stats_read(&st->misses); 2425 } while (u64_stats_fetch_retry(&st->syncp, start)); 2426 nsecs += tnsecs; 2427 cnt += tcnt; 2428 misses += tmisses; 2429 } 2430 stats->nsecs = nsecs; 2431 stats->cnt = cnt; 2432 stats->misses = misses; 2433 } 2434 2435 #ifdef CONFIG_PROC_FS 2436 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) 2437 { 2438 const struct bpf_prog *prog = filp->private_data; 2439 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 2440 struct bpf_prog_kstats stats; 2441 2442 bpf_prog_get_stats(prog, &stats); 2443 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 2444 seq_printf(m, 2445 "prog_type:\t%u\n" 2446 "prog_jited:\t%u\n" 2447 "prog_tag:\t%s\n" 2448 "memlock:\t%llu\n" 2449 "prog_id:\t%u\n" 2450 "run_time_ns:\t%llu\n" 2451 "run_cnt:\t%llu\n" 2452 "recursion_misses:\t%llu\n" 2453 "verified_insns:\t%u\n", 2454 prog->type, 2455 prog->jited, 2456 prog_tag, 2457 prog->pages * 1ULL << PAGE_SHIFT, 2458 prog->aux->id, 2459 stats.nsecs, 2460 stats.cnt, 2461 stats.misses, 2462 prog->aux->verified_insns); 2463 } 2464 #endif 2465 2466 const struct file_operations bpf_prog_fops = { 2467 #ifdef CONFIG_PROC_FS 2468 .show_fdinfo = bpf_prog_show_fdinfo, 2469 #endif 2470 .release = bpf_prog_release, 2471 .read = bpf_dummy_read, 2472 .write = bpf_dummy_write, 2473 }; 2474 2475 int bpf_prog_new_fd(struct bpf_prog *prog) 2476 { 2477 int ret; 2478 2479 ret = security_bpf_prog(prog); 2480 if (ret < 0) 2481 return ret; 2482 2483 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, 2484 O_RDWR | O_CLOEXEC); 2485 } 2486 2487 void bpf_prog_add(struct bpf_prog *prog, int i) 2488 { 2489 atomic64_add(i, &prog->aux->refcnt); 2490 } 2491 EXPORT_SYMBOL_GPL(bpf_prog_add); 2492 2493 void bpf_prog_sub(struct bpf_prog *prog, int i) 2494 { 2495 /* Only to be used for undoing previous bpf_prog_add() in some 2496 * error path. We still know that another entity in our call 2497 * path holds a reference to the program, thus atomic_sub() can 2498 * be safely used in such cases! 2499 */ 2500 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); 2501 } 2502 EXPORT_SYMBOL_GPL(bpf_prog_sub); 2503 2504 void bpf_prog_inc(struct bpf_prog *prog) 2505 { 2506 atomic64_inc(&prog->aux->refcnt); 2507 } 2508 EXPORT_SYMBOL_GPL(bpf_prog_inc); 2509 2510 /* prog_idr_lock should have been held */ 2511 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) 2512 { 2513 int refold; 2514 2515 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); 2516 2517 if (!refold) 2518 return ERR_PTR(-ENOENT); 2519 2520 return prog; 2521 } 2522 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); 2523 2524 bool bpf_prog_get_ok(struct bpf_prog *prog, 2525 enum bpf_prog_type *attach_type, bool attach_drv) 2526 { 2527 /* not an attachment, just a refcount inc, always allow */ 2528 if (!attach_type) 2529 return true; 2530 2531 if (prog->type != *attach_type) 2532 return false; 2533 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) 2534 return false; 2535 2536 return true; 2537 } 2538 2539 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, 2540 bool attach_drv) 2541 { 2542 CLASS(fd, f)(ufd); 2543 struct bpf_prog *prog; 2544 2545 if (fd_empty(f)) 2546 return ERR_PTR(-EBADF); 2547 if (fd_file(f)->f_op != &bpf_prog_fops) 2548 return ERR_PTR(-EINVAL); 2549 2550 prog = fd_file(f)->private_data; 2551 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) 2552 return ERR_PTR(-EINVAL); 2553 2554 bpf_prog_inc(prog); 2555 return prog; 2556 } 2557 2558 struct bpf_prog *bpf_prog_get(u32 ufd) 2559 { 2560 return __bpf_prog_get(ufd, NULL, false); 2561 } 2562 2563 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, 2564 bool attach_drv) 2565 { 2566 return __bpf_prog_get(ufd, &type, attach_drv); 2567 } 2568 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); 2569 2570 /* Initially all BPF programs could be loaded w/o specifying 2571 * expected_attach_type. Later for some of them specifying expected_attach_type 2572 * at load time became required so that program could be validated properly. 2573 * Programs of types that are allowed to be loaded both w/ and w/o (for 2574 * backward compatibility) expected_attach_type, should have the default attach 2575 * type assigned to expected_attach_type for the latter case, so that it can be 2576 * validated later at attach time. 2577 * 2578 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if 2579 * prog type requires it but has some attach types that have to be backward 2580 * compatible. 2581 */ 2582 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) 2583 { 2584 switch (attr->prog_type) { 2585 case BPF_PROG_TYPE_CGROUP_SOCK: 2586 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't 2587 * exist so checking for non-zero is the way to go here. 2588 */ 2589 if (!attr->expected_attach_type) 2590 attr->expected_attach_type = 2591 BPF_CGROUP_INET_SOCK_CREATE; 2592 break; 2593 case BPF_PROG_TYPE_SK_REUSEPORT: 2594 if (!attr->expected_attach_type) 2595 attr->expected_attach_type = 2596 BPF_SK_REUSEPORT_SELECT; 2597 break; 2598 } 2599 } 2600 2601 static int 2602 bpf_prog_load_check_attach(enum bpf_prog_type prog_type, 2603 enum bpf_attach_type expected_attach_type, 2604 struct btf *attach_btf, u32 btf_id, 2605 struct bpf_prog *dst_prog) 2606 { 2607 if (btf_id) { 2608 if (btf_id > BTF_MAX_TYPE) 2609 return -EINVAL; 2610 2611 if (!attach_btf && !dst_prog) 2612 return -EINVAL; 2613 2614 switch (prog_type) { 2615 case BPF_PROG_TYPE_TRACING: 2616 case BPF_PROG_TYPE_LSM: 2617 case BPF_PROG_TYPE_STRUCT_OPS: 2618 case BPF_PROG_TYPE_EXT: 2619 break; 2620 default: 2621 return -EINVAL; 2622 } 2623 } 2624 2625 if (attach_btf && (!btf_id || dst_prog)) 2626 return -EINVAL; 2627 2628 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && 2629 prog_type != BPF_PROG_TYPE_EXT) 2630 return -EINVAL; 2631 2632 switch (prog_type) { 2633 case BPF_PROG_TYPE_CGROUP_SOCK: 2634 switch (expected_attach_type) { 2635 case BPF_CGROUP_INET_SOCK_CREATE: 2636 case BPF_CGROUP_INET_SOCK_RELEASE: 2637 case BPF_CGROUP_INET4_POST_BIND: 2638 case BPF_CGROUP_INET6_POST_BIND: 2639 return 0; 2640 default: 2641 return -EINVAL; 2642 } 2643 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2644 switch (expected_attach_type) { 2645 case BPF_CGROUP_INET4_BIND: 2646 case BPF_CGROUP_INET6_BIND: 2647 case BPF_CGROUP_INET4_CONNECT: 2648 case BPF_CGROUP_INET6_CONNECT: 2649 case BPF_CGROUP_UNIX_CONNECT: 2650 case BPF_CGROUP_INET4_GETPEERNAME: 2651 case BPF_CGROUP_INET6_GETPEERNAME: 2652 case BPF_CGROUP_UNIX_GETPEERNAME: 2653 case BPF_CGROUP_INET4_GETSOCKNAME: 2654 case BPF_CGROUP_INET6_GETSOCKNAME: 2655 case BPF_CGROUP_UNIX_GETSOCKNAME: 2656 case BPF_CGROUP_UDP4_SENDMSG: 2657 case BPF_CGROUP_UDP6_SENDMSG: 2658 case BPF_CGROUP_UNIX_SENDMSG: 2659 case BPF_CGROUP_UDP4_RECVMSG: 2660 case BPF_CGROUP_UDP6_RECVMSG: 2661 case BPF_CGROUP_UNIX_RECVMSG: 2662 return 0; 2663 default: 2664 return -EINVAL; 2665 } 2666 case BPF_PROG_TYPE_CGROUP_SKB: 2667 switch (expected_attach_type) { 2668 case BPF_CGROUP_INET_INGRESS: 2669 case BPF_CGROUP_INET_EGRESS: 2670 return 0; 2671 default: 2672 return -EINVAL; 2673 } 2674 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2675 switch (expected_attach_type) { 2676 case BPF_CGROUP_SETSOCKOPT: 2677 case BPF_CGROUP_GETSOCKOPT: 2678 return 0; 2679 default: 2680 return -EINVAL; 2681 } 2682 case BPF_PROG_TYPE_SK_LOOKUP: 2683 if (expected_attach_type == BPF_SK_LOOKUP) 2684 return 0; 2685 return -EINVAL; 2686 case BPF_PROG_TYPE_SK_REUSEPORT: 2687 switch (expected_attach_type) { 2688 case BPF_SK_REUSEPORT_SELECT: 2689 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: 2690 return 0; 2691 default: 2692 return -EINVAL; 2693 } 2694 case BPF_PROG_TYPE_NETFILTER: 2695 if (expected_attach_type == BPF_NETFILTER) 2696 return 0; 2697 return -EINVAL; 2698 case BPF_PROG_TYPE_SYSCALL: 2699 case BPF_PROG_TYPE_EXT: 2700 if (expected_attach_type) 2701 return -EINVAL; 2702 fallthrough; 2703 default: 2704 return 0; 2705 } 2706 } 2707 2708 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) 2709 { 2710 switch (prog_type) { 2711 case BPF_PROG_TYPE_SCHED_CLS: 2712 case BPF_PROG_TYPE_SCHED_ACT: 2713 case BPF_PROG_TYPE_XDP: 2714 case BPF_PROG_TYPE_LWT_IN: 2715 case BPF_PROG_TYPE_LWT_OUT: 2716 case BPF_PROG_TYPE_LWT_XMIT: 2717 case BPF_PROG_TYPE_LWT_SEG6LOCAL: 2718 case BPF_PROG_TYPE_SK_SKB: 2719 case BPF_PROG_TYPE_SK_MSG: 2720 case BPF_PROG_TYPE_FLOW_DISSECTOR: 2721 case BPF_PROG_TYPE_CGROUP_DEVICE: 2722 case BPF_PROG_TYPE_CGROUP_SOCK: 2723 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 2724 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 2725 case BPF_PROG_TYPE_CGROUP_SYSCTL: 2726 case BPF_PROG_TYPE_SOCK_OPS: 2727 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2728 case BPF_PROG_TYPE_NETFILTER: 2729 return true; 2730 case BPF_PROG_TYPE_CGROUP_SKB: 2731 /* always unpriv */ 2732 case BPF_PROG_TYPE_SK_REUSEPORT: 2733 /* equivalent to SOCKET_FILTER. need CAP_BPF only */ 2734 default: 2735 return false; 2736 } 2737 } 2738 2739 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) 2740 { 2741 switch (prog_type) { 2742 case BPF_PROG_TYPE_KPROBE: 2743 case BPF_PROG_TYPE_TRACEPOINT: 2744 case BPF_PROG_TYPE_PERF_EVENT: 2745 case BPF_PROG_TYPE_RAW_TRACEPOINT: 2746 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 2747 case BPF_PROG_TYPE_TRACING: 2748 case BPF_PROG_TYPE_LSM: 2749 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ 2750 case BPF_PROG_TYPE_EXT: /* extends any prog */ 2751 return true; 2752 default: 2753 return false; 2754 } 2755 } 2756 2757 /* last field in 'union bpf_attr' used by this command */ 2758 #define BPF_PROG_LOAD_LAST_FIELD fd_array_cnt 2759 2760 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) 2761 { 2762 enum bpf_prog_type type = attr->prog_type; 2763 struct bpf_prog *prog, *dst_prog = NULL; 2764 struct btf *attach_btf = NULL; 2765 struct bpf_token *token = NULL; 2766 bool bpf_cap; 2767 int err; 2768 char license[128]; 2769 2770 if (CHECK_ATTR(BPF_PROG_LOAD)) 2771 return -EINVAL; 2772 2773 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | 2774 BPF_F_ANY_ALIGNMENT | 2775 BPF_F_TEST_STATE_FREQ | 2776 BPF_F_SLEEPABLE | 2777 BPF_F_TEST_RND_HI32 | 2778 BPF_F_XDP_HAS_FRAGS | 2779 BPF_F_XDP_DEV_BOUND_ONLY | 2780 BPF_F_TEST_REG_INVARIANTS | 2781 BPF_F_TOKEN_FD)) 2782 return -EINVAL; 2783 2784 bpf_prog_load_fixup_attach_type(attr); 2785 2786 if (attr->prog_flags & BPF_F_TOKEN_FD) { 2787 token = bpf_token_get_from_fd(attr->prog_token_fd); 2788 if (IS_ERR(token)) 2789 return PTR_ERR(token); 2790 /* if current token doesn't grant prog loading permissions, 2791 * then we can't use this token, so ignore it and rely on 2792 * system-wide capabilities checks 2793 */ 2794 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || 2795 !bpf_token_allow_prog_type(token, attr->prog_type, 2796 attr->expected_attach_type)) { 2797 bpf_token_put(token); 2798 token = NULL; 2799 } 2800 } 2801 2802 bpf_cap = bpf_token_capable(token, CAP_BPF); 2803 err = -EPERM; 2804 2805 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && 2806 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && 2807 !bpf_cap) 2808 goto put_token; 2809 2810 /* Intent here is for unprivileged_bpf_disabled to block BPF program 2811 * creation for unprivileged users; other actions depend 2812 * on fd availability and access to bpffs, so are dependent on 2813 * object creation success. Even with unprivileged BPF disabled, 2814 * capability checks are still carried out for these 2815 * and other operations. 2816 */ 2817 if (sysctl_unprivileged_bpf_disabled && !bpf_cap) 2818 goto put_token; 2819 2820 if (attr->insn_cnt == 0 || 2821 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { 2822 err = -E2BIG; 2823 goto put_token; 2824 } 2825 if (type != BPF_PROG_TYPE_SOCKET_FILTER && 2826 type != BPF_PROG_TYPE_CGROUP_SKB && 2827 !bpf_cap) 2828 goto put_token; 2829 2830 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) 2831 goto put_token; 2832 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) 2833 goto put_token; 2834 2835 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog 2836 * or btf, we need to check which one it is 2837 */ 2838 if (attr->attach_prog_fd) { 2839 dst_prog = bpf_prog_get(attr->attach_prog_fd); 2840 if (IS_ERR(dst_prog)) { 2841 dst_prog = NULL; 2842 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); 2843 if (IS_ERR(attach_btf)) { 2844 err = -EINVAL; 2845 goto put_token; 2846 } 2847 if (!btf_is_kernel(attach_btf)) { 2848 /* attaching through specifying bpf_prog's BTF 2849 * objects directly might be supported eventually 2850 */ 2851 btf_put(attach_btf); 2852 err = -ENOTSUPP; 2853 goto put_token; 2854 } 2855 } 2856 } else if (attr->attach_btf_id) { 2857 /* fall back to vmlinux BTF, if BTF type ID is specified */ 2858 attach_btf = bpf_get_btf_vmlinux(); 2859 if (IS_ERR(attach_btf)) { 2860 err = PTR_ERR(attach_btf); 2861 goto put_token; 2862 } 2863 if (!attach_btf) { 2864 err = -EINVAL; 2865 goto put_token; 2866 } 2867 btf_get(attach_btf); 2868 } 2869 2870 if (bpf_prog_load_check_attach(type, attr->expected_attach_type, 2871 attach_btf, attr->attach_btf_id, 2872 dst_prog)) { 2873 if (dst_prog) 2874 bpf_prog_put(dst_prog); 2875 if (attach_btf) 2876 btf_put(attach_btf); 2877 err = -EINVAL; 2878 goto put_token; 2879 } 2880 2881 /* plain bpf_prog allocation */ 2882 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); 2883 if (!prog) { 2884 if (dst_prog) 2885 bpf_prog_put(dst_prog); 2886 if (attach_btf) 2887 btf_put(attach_btf); 2888 err = -EINVAL; 2889 goto put_token; 2890 } 2891 2892 prog->expected_attach_type = attr->expected_attach_type; 2893 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); 2894 prog->aux->attach_btf = attach_btf; 2895 prog->aux->attach_btf_id = attr->attach_btf_id; 2896 prog->aux->dst_prog = dst_prog; 2897 prog->aux->dev_bound = !!attr->prog_ifindex; 2898 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; 2899 2900 /* move token into prog->aux, reuse taken refcnt */ 2901 prog->aux->token = token; 2902 token = NULL; 2903 2904 prog->aux->user = get_current_user(); 2905 prog->len = attr->insn_cnt; 2906 2907 err = -EFAULT; 2908 if (copy_from_bpfptr(prog->insns, 2909 make_bpfptr(attr->insns, uattr.is_kernel), 2910 bpf_prog_insn_size(prog)) != 0) 2911 goto free_prog; 2912 /* copy eBPF program license from user space */ 2913 if (strncpy_from_bpfptr(license, 2914 make_bpfptr(attr->license, uattr.is_kernel), 2915 sizeof(license) - 1) < 0) 2916 goto free_prog; 2917 license[sizeof(license) - 1] = 0; 2918 2919 /* eBPF programs must be GPL compatible to use GPL-ed functions */ 2920 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; 2921 2922 prog->orig_prog = NULL; 2923 prog->jited = 0; 2924 2925 atomic64_set(&prog->aux->refcnt, 1); 2926 2927 if (bpf_prog_is_dev_bound(prog->aux)) { 2928 err = bpf_prog_dev_bound_init(prog, attr); 2929 if (err) 2930 goto free_prog; 2931 } 2932 2933 if (type == BPF_PROG_TYPE_EXT && dst_prog && 2934 bpf_prog_is_dev_bound(dst_prog->aux)) { 2935 err = bpf_prog_dev_bound_inherit(prog, dst_prog); 2936 if (err) 2937 goto free_prog; 2938 } 2939 2940 /* 2941 * Bookkeeping for managing the program attachment chain. 2942 * 2943 * It might be tempting to set attach_tracing_prog flag at the attachment 2944 * time, but this will not prevent from loading bunch of tracing prog 2945 * first, then attach them one to another. 2946 * 2947 * The flag attach_tracing_prog is set for the whole program lifecycle, and 2948 * doesn't have to be cleared in bpf_tracing_link_release, since tracing 2949 * programs cannot change attachment target. 2950 */ 2951 if (type == BPF_PROG_TYPE_TRACING && dst_prog && 2952 dst_prog->type == BPF_PROG_TYPE_TRACING) { 2953 prog->aux->attach_tracing_prog = true; 2954 } 2955 2956 /* find program type: socket_filter vs tracing_filter */ 2957 err = find_prog_type(type, prog); 2958 if (err < 0) 2959 goto free_prog; 2960 2961 prog->aux->load_time = ktime_get_boottime_ns(); 2962 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, 2963 sizeof(attr->prog_name)); 2964 if (err < 0) 2965 goto free_prog; 2966 2967 err = security_bpf_prog_load(prog, attr, token, uattr.is_kernel); 2968 if (err) 2969 goto free_prog_sec; 2970 2971 /* run eBPF verifier */ 2972 err = bpf_check(&prog, attr, uattr, uattr_size); 2973 if (err < 0) 2974 goto free_used_maps; 2975 2976 prog = bpf_prog_select_runtime(prog, &err); 2977 if (err < 0) 2978 goto free_used_maps; 2979 2980 err = bpf_prog_alloc_id(prog); 2981 if (err) 2982 goto free_used_maps; 2983 2984 /* Upon success of bpf_prog_alloc_id(), the BPF prog is 2985 * effectively publicly exposed. However, retrieving via 2986 * bpf_prog_get_fd_by_id() will take another reference, 2987 * therefore it cannot be gone underneath us. 2988 * 2989 * Only for the time /after/ successful bpf_prog_new_fd() 2990 * and before returning to userspace, we might just hold 2991 * one reference and any parallel close on that fd could 2992 * rip everything out. Hence, below notifications must 2993 * happen before bpf_prog_new_fd(). 2994 * 2995 * Also, any failure handling from this point onwards must 2996 * be using bpf_prog_put() given the program is exposed. 2997 */ 2998 bpf_prog_kallsyms_add(prog); 2999 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); 3000 bpf_audit_prog(prog, BPF_AUDIT_LOAD); 3001 3002 err = bpf_prog_new_fd(prog); 3003 if (err < 0) 3004 bpf_prog_put(prog); 3005 return err; 3006 3007 free_used_maps: 3008 /* In case we have subprogs, we need to wait for a grace 3009 * period before we can tear down JIT memory since symbols 3010 * are already exposed under kallsyms. 3011 */ 3012 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); 3013 return err; 3014 3015 free_prog_sec: 3016 security_bpf_prog_free(prog); 3017 free_prog: 3018 free_uid(prog->aux->user); 3019 if (prog->aux->attach_btf) 3020 btf_put(prog->aux->attach_btf); 3021 bpf_prog_free(prog); 3022 put_token: 3023 bpf_token_put(token); 3024 return err; 3025 } 3026 3027 #define BPF_OBJ_LAST_FIELD path_fd 3028 3029 static int bpf_obj_pin(const union bpf_attr *attr) 3030 { 3031 int path_fd; 3032 3033 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) 3034 return -EINVAL; 3035 3036 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3037 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3038 return -EINVAL; 3039 3040 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3041 return bpf_obj_pin_user(attr->bpf_fd, path_fd, 3042 u64_to_user_ptr(attr->pathname)); 3043 } 3044 3045 static int bpf_obj_get(const union bpf_attr *attr) 3046 { 3047 int path_fd; 3048 3049 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || 3050 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) 3051 return -EINVAL; 3052 3053 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ 3054 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) 3055 return -EINVAL; 3056 3057 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; 3058 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), 3059 attr->file_flags); 3060 } 3061 3062 /* bpf_link_init_sleepable() allows to specify whether BPF link itself has 3063 * "sleepable" semantics, which normally would mean that BPF link's attach 3064 * hook can dereference link or link's underlying program for some time after 3065 * detachment due to RCU Tasks Trace-based lifetime protection scheme. 3066 * BPF program itself can be non-sleepable, yet, because it's transitively 3067 * reachable through BPF link, its freeing has to be delayed until after RCU 3068 * Tasks Trace GP. 3069 */ 3070 void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type, 3071 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3072 enum bpf_attach_type attach_type, bool sleepable) 3073 { 3074 WARN_ON(ops->dealloc && ops->dealloc_deferred); 3075 atomic64_set(&link->refcnt, 1); 3076 link->type = type; 3077 link->sleepable = sleepable; 3078 link->id = 0; 3079 link->ops = ops; 3080 link->prog = prog; 3081 link->attach_type = attach_type; 3082 } 3083 3084 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, 3085 const struct bpf_link_ops *ops, struct bpf_prog *prog, 3086 enum bpf_attach_type attach_type) 3087 { 3088 bpf_link_init_sleepable(link, type, ops, prog, attach_type, false); 3089 } 3090 3091 static void bpf_link_free_id(int id) 3092 { 3093 if (!id) 3094 return; 3095 3096 spin_lock_bh(&link_idr_lock); 3097 idr_remove(&link_idr, id); 3098 spin_unlock_bh(&link_idr_lock); 3099 } 3100 3101 /* Clean up bpf_link and corresponding anon_inode file and FD. After 3102 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred 3103 * anon_inode's release() call. This helper marks bpf_link as 3104 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt 3105 * is not decremented, it's the responsibility of a calling code that failed 3106 * to complete bpf_link initialization. 3107 * This helper eventually calls link's dealloc callback, but does not call 3108 * link's release callback. 3109 */ 3110 void bpf_link_cleanup(struct bpf_link_primer *primer) 3111 { 3112 primer->link->prog = NULL; 3113 bpf_link_free_id(primer->id); 3114 fput(primer->file); 3115 put_unused_fd(primer->fd); 3116 } 3117 3118 void bpf_link_inc(struct bpf_link *link) 3119 { 3120 atomic64_inc(&link->refcnt); 3121 } 3122 3123 static void bpf_link_dealloc(struct bpf_link *link) 3124 { 3125 /* now that we know that bpf_link itself can't be reached, put underlying BPF program */ 3126 if (link->prog) 3127 bpf_prog_put(link->prog); 3128 3129 /* free bpf_link and its containing memory */ 3130 if (link->ops->dealloc_deferred) 3131 link->ops->dealloc_deferred(link); 3132 else 3133 link->ops->dealloc(link); 3134 } 3135 3136 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) 3137 { 3138 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); 3139 3140 bpf_link_dealloc(link); 3141 } 3142 3143 static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu) 3144 { 3145 if (rcu_trace_implies_rcu_gp()) 3146 bpf_link_defer_dealloc_rcu_gp(rcu); 3147 else 3148 call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp); 3149 } 3150 3151 /* bpf_link_free is guaranteed to be called from process context */ 3152 static void bpf_link_free(struct bpf_link *link) 3153 { 3154 const struct bpf_link_ops *ops = link->ops; 3155 3156 bpf_link_free_id(link->id); 3157 /* detach BPF program, clean up used resources */ 3158 if (link->prog) 3159 ops->release(link); 3160 if (ops->dealloc_deferred) { 3161 /* Schedule BPF link deallocation, which will only then 3162 * trigger putting BPF program refcount. 3163 * If underlying BPF program is sleepable or BPF link's target 3164 * attach hookpoint is sleepable or otherwise requires RCU GPs 3165 * to ensure link and its underlying BPF program is not 3166 * reachable anymore, we need to first wait for RCU tasks 3167 * trace sync, and then go through "classic" RCU grace period 3168 */ 3169 if (link->sleepable || (link->prog && link->prog->sleepable)) 3170 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp); 3171 else 3172 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); 3173 } else if (ops->dealloc) { 3174 bpf_link_dealloc(link); 3175 } 3176 } 3177 3178 static void bpf_link_put_deferred(struct work_struct *work) 3179 { 3180 struct bpf_link *link = container_of(work, struct bpf_link, work); 3181 3182 bpf_link_free(link); 3183 } 3184 3185 /* bpf_link_put might be called from atomic context. It needs to be called 3186 * from sleepable context in order to acquire sleeping locks during the process. 3187 */ 3188 void bpf_link_put(struct bpf_link *link) 3189 { 3190 if (!atomic64_dec_and_test(&link->refcnt)) 3191 return; 3192 3193 INIT_WORK(&link->work, bpf_link_put_deferred); 3194 schedule_work(&link->work); 3195 } 3196 EXPORT_SYMBOL(bpf_link_put); 3197 3198 static void bpf_link_put_direct(struct bpf_link *link) 3199 { 3200 if (!atomic64_dec_and_test(&link->refcnt)) 3201 return; 3202 bpf_link_free(link); 3203 } 3204 3205 static int bpf_link_release(struct inode *inode, struct file *filp) 3206 { 3207 struct bpf_link *link = filp->private_data; 3208 3209 bpf_link_put_direct(link); 3210 return 0; 3211 } 3212 3213 #ifdef CONFIG_PROC_FS 3214 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) 3215 #define BPF_MAP_TYPE(_id, _ops) 3216 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, 3217 static const char *bpf_link_type_strs[] = { 3218 [BPF_LINK_TYPE_UNSPEC] = "<invalid>", 3219 #include <linux/bpf_types.h> 3220 }; 3221 #undef BPF_PROG_TYPE 3222 #undef BPF_MAP_TYPE 3223 #undef BPF_LINK_TYPE 3224 3225 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) 3226 { 3227 const struct bpf_link *link = filp->private_data; 3228 const struct bpf_prog *prog = link->prog; 3229 enum bpf_link_type type = link->type; 3230 char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; 3231 3232 if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) { 3233 if (link->type == BPF_LINK_TYPE_KPROBE_MULTI) 3234 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_KPROBE_MULTI_RETURN ? 3235 "kretprobe_multi" : "kprobe_multi"); 3236 else if (link->type == BPF_LINK_TYPE_UPROBE_MULTI) 3237 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_UPROBE_MULTI_RETURN ? 3238 "uretprobe_multi" : "uprobe_multi"); 3239 else 3240 seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]); 3241 } else { 3242 WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type); 3243 seq_printf(m, "link_type:\t<%u>\n", type); 3244 } 3245 seq_printf(m, "link_id:\t%u\n", link->id); 3246 3247 if (prog) { 3248 bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); 3249 seq_printf(m, 3250 "prog_tag:\t%s\n" 3251 "prog_id:\t%u\n", 3252 prog_tag, 3253 prog->aux->id); 3254 } 3255 if (link->ops->show_fdinfo) 3256 link->ops->show_fdinfo(link, m); 3257 } 3258 #endif 3259 3260 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts) 3261 { 3262 struct bpf_link *link = file->private_data; 3263 3264 return link->ops->poll(file, pts); 3265 } 3266 3267 static const struct file_operations bpf_link_fops = { 3268 #ifdef CONFIG_PROC_FS 3269 .show_fdinfo = bpf_link_show_fdinfo, 3270 #endif 3271 .release = bpf_link_release, 3272 .read = bpf_dummy_read, 3273 .write = bpf_dummy_write, 3274 }; 3275 3276 static const struct file_operations bpf_link_fops_poll = { 3277 #ifdef CONFIG_PROC_FS 3278 .show_fdinfo = bpf_link_show_fdinfo, 3279 #endif 3280 .release = bpf_link_release, 3281 .read = bpf_dummy_read, 3282 .write = bpf_dummy_write, 3283 .poll = bpf_link_poll, 3284 }; 3285 3286 static int bpf_link_alloc_id(struct bpf_link *link) 3287 { 3288 int id; 3289 3290 idr_preload(GFP_KERNEL); 3291 spin_lock_bh(&link_idr_lock); 3292 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); 3293 spin_unlock_bh(&link_idr_lock); 3294 idr_preload_end(); 3295 3296 return id; 3297 } 3298 3299 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, 3300 * reserving unused FD and allocating ID from link_idr. This is to be paired 3301 * with bpf_link_settle() to install FD and ID and expose bpf_link to 3302 * user-space, if bpf_link is successfully attached. If not, bpf_link and 3303 * pre-allocated resources are to be freed with bpf_cleanup() call. All the 3304 * transient state is passed around in struct bpf_link_primer. 3305 * This is preferred way to create and initialize bpf_link, especially when 3306 * there are complicated and expensive operations in between creating bpf_link 3307 * itself and attaching it to BPF hook. By using bpf_link_prime() and 3308 * bpf_link_settle() kernel code using bpf_link doesn't have to perform 3309 * expensive (and potentially failing) roll back operations in a rare case 3310 * that file, FD, or ID can't be allocated. 3311 */ 3312 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) 3313 { 3314 struct file *file; 3315 int fd, id; 3316 3317 fd = get_unused_fd_flags(O_CLOEXEC); 3318 if (fd < 0) 3319 return fd; 3320 3321 3322 id = bpf_link_alloc_id(link); 3323 if (id < 0) { 3324 put_unused_fd(fd); 3325 return id; 3326 } 3327 3328 file = anon_inode_getfile("bpf_link", 3329 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3330 link, O_CLOEXEC); 3331 if (IS_ERR(file)) { 3332 bpf_link_free_id(id); 3333 put_unused_fd(fd); 3334 return PTR_ERR(file); 3335 } 3336 3337 primer->link = link; 3338 primer->file = file; 3339 primer->fd = fd; 3340 primer->id = id; 3341 return 0; 3342 } 3343 3344 int bpf_link_settle(struct bpf_link_primer *primer) 3345 { 3346 /* make bpf_link fetchable by ID */ 3347 spin_lock_bh(&link_idr_lock); 3348 primer->link->id = primer->id; 3349 spin_unlock_bh(&link_idr_lock); 3350 /* make bpf_link fetchable by FD */ 3351 fd_install(primer->fd, primer->file); 3352 /* pass through installed FD */ 3353 return primer->fd; 3354 } 3355 3356 int bpf_link_new_fd(struct bpf_link *link) 3357 { 3358 return anon_inode_getfd("bpf-link", 3359 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, 3360 link, O_CLOEXEC); 3361 } 3362 3363 struct bpf_link *bpf_link_get_from_fd(u32 ufd) 3364 { 3365 CLASS(fd, f)(ufd); 3366 struct bpf_link *link; 3367 3368 if (fd_empty(f)) 3369 return ERR_PTR(-EBADF); 3370 if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll) 3371 return ERR_PTR(-EINVAL); 3372 3373 link = fd_file(f)->private_data; 3374 bpf_link_inc(link); 3375 return link; 3376 } 3377 EXPORT_SYMBOL_NS(bpf_link_get_from_fd, "BPF_INTERNAL"); 3378 3379 static void bpf_tracing_link_release(struct bpf_link *link) 3380 { 3381 struct bpf_tracing_link *tr_link = 3382 container_of(link, struct bpf_tracing_link, link.link); 3383 3384 WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, 3385 tr_link->trampoline, 3386 tr_link->tgt_prog)); 3387 3388 bpf_trampoline_put(tr_link->trampoline); 3389 3390 /* tgt_prog is NULL if target is a kernel function */ 3391 if (tr_link->tgt_prog) 3392 bpf_prog_put(tr_link->tgt_prog); 3393 } 3394 3395 static void bpf_tracing_link_dealloc(struct bpf_link *link) 3396 { 3397 struct bpf_tracing_link *tr_link = 3398 container_of(link, struct bpf_tracing_link, link.link); 3399 3400 kfree(tr_link); 3401 } 3402 3403 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, 3404 struct seq_file *seq) 3405 { 3406 struct bpf_tracing_link *tr_link = 3407 container_of(link, struct bpf_tracing_link, link.link); 3408 u32 target_btf_id, target_obj_id; 3409 3410 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3411 &target_obj_id, &target_btf_id); 3412 seq_printf(seq, 3413 "attach_type:\t%d\n" 3414 "target_obj_id:\t%u\n" 3415 "target_btf_id:\t%u\n" 3416 "cookie:\t%llu\n", 3417 link->attach_type, 3418 target_obj_id, 3419 target_btf_id, 3420 tr_link->link.cookie); 3421 } 3422 3423 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, 3424 struct bpf_link_info *info) 3425 { 3426 struct bpf_tracing_link *tr_link = 3427 container_of(link, struct bpf_tracing_link, link.link); 3428 3429 info->tracing.attach_type = link->attach_type; 3430 info->tracing.cookie = tr_link->link.cookie; 3431 bpf_trampoline_unpack_key(tr_link->trampoline->key, 3432 &info->tracing.target_obj_id, 3433 &info->tracing.target_btf_id); 3434 3435 return 0; 3436 } 3437 3438 static const struct bpf_link_ops bpf_tracing_link_lops = { 3439 .release = bpf_tracing_link_release, 3440 .dealloc = bpf_tracing_link_dealloc, 3441 .show_fdinfo = bpf_tracing_link_show_fdinfo, 3442 .fill_link_info = bpf_tracing_link_fill_link_info, 3443 }; 3444 3445 static int bpf_tracing_prog_attach(struct bpf_prog *prog, 3446 int tgt_prog_fd, 3447 u32 btf_id, 3448 u64 bpf_cookie, 3449 enum bpf_attach_type attach_type) 3450 { 3451 struct bpf_link_primer link_primer; 3452 struct bpf_prog *tgt_prog = NULL; 3453 struct bpf_trampoline *tr = NULL; 3454 struct bpf_tracing_link *link; 3455 u64 key = 0; 3456 int err; 3457 3458 switch (prog->type) { 3459 case BPF_PROG_TYPE_TRACING: 3460 if (prog->expected_attach_type != BPF_TRACE_FENTRY && 3461 prog->expected_attach_type != BPF_TRACE_FEXIT && 3462 prog->expected_attach_type != BPF_MODIFY_RETURN) { 3463 err = -EINVAL; 3464 goto out_put_prog; 3465 } 3466 break; 3467 case BPF_PROG_TYPE_EXT: 3468 if (prog->expected_attach_type != 0) { 3469 err = -EINVAL; 3470 goto out_put_prog; 3471 } 3472 break; 3473 case BPF_PROG_TYPE_LSM: 3474 if (prog->expected_attach_type != BPF_LSM_MAC) { 3475 err = -EINVAL; 3476 goto out_put_prog; 3477 } 3478 break; 3479 default: 3480 err = -EINVAL; 3481 goto out_put_prog; 3482 } 3483 3484 if (!!tgt_prog_fd != !!btf_id) { 3485 err = -EINVAL; 3486 goto out_put_prog; 3487 } 3488 3489 if (tgt_prog_fd) { 3490 /* 3491 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this 3492 * part would be changed to implement the same for 3493 * BPF_PROG_TYPE_TRACING, do not forget to update the way how 3494 * attach_tracing_prog flag is set. 3495 */ 3496 if (prog->type != BPF_PROG_TYPE_EXT) { 3497 err = -EINVAL; 3498 goto out_put_prog; 3499 } 3500 3501 tgt_prog = bpf_prog_get(tgt_prog_fd); 3502 if (IS_ERR(tgt_prog)) { 3503 err = PTR_ERR(tgt_prog); 3504 tgt_prog = NULL; 3505 goto out_put_prog; 3506 } 3507 3508 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); 3509 } 3510 3511 link = kzalloc(sizeof(*link), GFP_USER); 3512 if (!link) { 3513 err = -ENOMEM; 3514 goto out_put_prog; 3515 } 3516 bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, 3517 &bpf_tracing_link_lops, prog, attach_type); 3518 3519 link->link.cookie = bpf_cookie; 3520 3521 mutex_lock(&prog->aux->dst_mutex); 3522 3523 /* There are a few possible cases here: 3524 * 3525 * - if prog->aux->dst_trampoline is set, the program was just loaded 3526 * and not yet attached to anything, so we can use the values stored 3527 * in prog->aux 3528 * 3529 * - if prog->aux->dst_trampoline is NULL, the program has already been 3530 * attached to a target and its initial target was cleared (below) 3531 * 3532 * - if tgt_prog != NULL, the caller specified tgt_prog_fd + 3533 * target_btf_id using the link_create API. 3534 * 3535 * - if tgt_prog == NULL when this function was called using the old 3536 * raw_tracepoint_open API, and we need a target from prog->aux 3537 * 3538 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program 3539 * was detached and is going for re-attachment. 3540 * 3541 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf 3542 * are NULL, then program was already attached and user did not provide 3543 * tgt_prog_fd so we have no way to find out or create trampoline 3544 */ 3545 if (!prog->aux->dst_trampoline && !tgt_prog) { 3546 /* 3547 * Allow re-attach for TRACING and LSM programs. If it's 3548 * currently linked, bpf_trampoline_link_prog will fail. 3549 * EXT programs need to specify tgt_prog_fd, so they 3550 * re-attach in separate code path. 3551 */ 3552 if (prog->type != BPF_PROG_TYPE_TRACING && 3553 prog->type != BPF_PROG_TYPE_LSM) { 3554 err = -EINVAL; 3555 goto out_unlock; 3556 } 3557 /* We can allow re-attach only if we have valid attach_btf. */ 3558 if (!prog->aux->attach_btf) { 3559 err = -EINVAL; 3560 goto out_unlock; 3561 } 3562 btf_id = prog->aux->attach_btf_id; 3563 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); 3564 } 3565 3566 if (!prog->aux->dst_trampoline || 3567 (key && key != prog->aux->dst_trampoline->key)) { 3568 /* If there is no saved target, or the specified target is 3569 * different from the destination specified at load time, we 3570 * need a new trampoline and a check for compatibility 3571 */ 3572 struct bpf_attach_target_info tgt_info = {}; 3573 3574 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, 3575 &tgt_info); 3576 if (err) 3577 goto out_unlock; 3578 3579 if (tgt_info.tgt_mod) { 3580 module_put(prog->aux->mod); 3581 prog->aux->mod = tgt_info.tgt_mod; 3582 } 3583 3584 tr = bpf_trampoline_get(key, &tgt_info); 3585 if (!tr) { 3586 err = -ENOMEM; 3587 goto out_unlock; 3588 } 3589 } else { 3590 /* The caller didn't specify a target, or the target was the 3591 * same as the destination supplied during program load. This 3592 * means we can reuse the trampoline and reference from program 3593 * load time, and there is no need to allocate a new one. This 3594 * can only happen once for any program, as the saved values in 3595 * prog->aux are cleared below. 3596 */ 3597 tr = prog->aux->dst_trampoline; 3598 tgt_prog = prog->aux->dst_prog; 3599 } 3600 3601 err = bpf_link_prime(&link->link.link, &link_primer); 3602 if (err) 3603 goto out_unlock; 3604 3605 err = bpf_trampoline_link_prog(&link->link, tr, tgt_prog); 3606 if (err) { 3607 bpf_link_cleanup(&link_primer); 3608 link = NULL; 3609 goto out_unlock; 3610 } 3611 3612 link->tgt_prog = tgt_prog; 3613 link->trampoline = tr; 3614 3615 /* Always clear the trampoline and target prog from prog->aux to make 3616 * sure the original attach destination is not kept alive after a 3617 * program is (re-)attached to another target. 3618 */ 3619 if (prog->aux->dst_prog && 3620 (tgt_prog_fd || tr != prog->aux->dst_trampoline)) 3621 /* got extra prog ref from syscall, or attaching to different prog */ 3622 bpf_prog_put(prog->aux->dst_prog); 3623 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) 3624 /* we allocated a new trampoline, so free the old one */ 3625 bpf_trampoline_put(prog->aux->dst_trampoline); 3626 3627 prog->aux->dst_prog = NULL; 3628 prog->aux->dst_trampoline = NULL; 3629 mutex_unlock(&prog->aux->dst_mutex); 3630 3631 return bpf_link_settle(&link_primer); 3632 out_unlock: 3633 if (tr && tr != prog->aux->dst_trampoline) 3634 bpf_trampoline_put(tr); 3635 mutex_unlock(&prog->aux->dst_mutex); 3636 kfree(link); 3637 out_put_prog: 3638 if (tgt_prog_fd && tgt_prog) 3639 bpf_prog_put(tgt_prog); 3640 return err; 3641 } 3642 3643 static void bpf_raw_tp_link_release(struct bpf_link *link) 3644 { 3645 struct bpf_raw_tp_link *raw_tp = 3646 container_of(link, struct bpf_raw_tp_link, link); 3647 3648 bpf_probe_unregister(raw_tp->btp, raw_tp); 3649 bpf_put_raw_tracepoint(raw_tp->btp); 3650 } 3651 3652 static void bpf_raw_tp_link_dealloc(struct bpf_link *link) 3653 { 3654 struct bpf_raw_tp_link *raw_tp = 3655 container_of(link, struct bpf_raw_tp_link, link); 3656 3657 kfree(raw_tp); 3658 } 3659 3660 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, 3661 struct seq_file *seq) 3662 { 3663 struct bpf_raw_tp_link *raw_tp_link = 3664 container_of(link, struct bpf_raw_tp_link, link); 3665 3666 seq_printf(seq, 3667 "tp_name:\t%s\n" 3668 "cookie:\t%llu\n", 3669 raw_tp_link->btp->tp->name, 3670 raw_tp_link->cookie); 3671 } 3672 3673 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, 3674 u32 len) 3675 { 3676 if (ulen >= len + 1) { 3677 if (copy_to_user(ubuf, buf, len + 1)) 3678 return -EFAULT; 3679 } else { 3680 char zero = '\0'; 3681 3682 if (copy_to_user(ubuf, buf, ulen - 1)) 3683 return -EFAULT; 3684 if (put_user(zero, ubuf + ulen - 1)) 3685 return -EFAULT; 3686 return -ENOSPC; 3687 } 3688 3689 return 0; 3690 } 3691 3692 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, 3693 struct bpf_link_info *info) 3694 { 3695 struct bpf_raw_tp_link *raw_tp_link = 3696 container_of(link, struct bpf_raw_tp_link, link); 3697 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); 3698 const char *tp_name = raw_tp_link->btp->tp->name; 3699 u32 ulen = info->raw_tracepoint.tp_name_len; 3700 size_t tp_len = strlen(tp_name); 3701 3702 if (!ulen ^ !ubuf) 3703 return -EINVAL; 3704 3705 info->raw_tracepoint.tp_name_len = tp_len + 1; 3706 info->raw_tracepoint.cookie = raw_tp_link->cookie; 3707 3708 if (!ubuf) 3709 return 0; 3710 3711 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); 3712 } 3713 3714 static const struct bpf_link_ops bpf_raw_tp_link_lops = { 3715 .release = bpf_raw_tp_link_release, 3716 .dealloc_deferred = bpf_raw_tp_link_dealloc, 3717 .show_fdinfo = bpf_raw_tp_link_show_fdinfo, 3718 .fill_link_info = bpf_raw_tp_link_fill_link_info, 3719 }; 3720 3721 #ifdef CONFIG_PERF_EVENTS 3722 struct bpf_perf_link { 3723 struct bpf_link link; 3724 struct file *perf_file; 3725 }; 3726 3727 static void bpf_perf_link_release(struct bpf_link *link) 3728 { 3729 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3730 struct perf_event *event = perf_link->perf_file->private_data; 3731 3732 perf_event_free_bpf_prog(event); 3733 fput(perf_link->perf_file); 3734 } 3735 3736 static void bpf_perf_link_dealloc(struct bpf_link *link) 3737 { 3738 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); 3739 3740 kfree(perf_link); 3741 } 3742 3743 static int bpf_perf_link_fill_common(const struct perf_event *event, 3744 char __user *uname, u32 *ulenp, 3745 u64 *probe_offset, u64 *probe_addr, 3746 u32 *fd_type, unsigned long *missed) 3747 { 3748 const char *buf; 3749 u32 prog_id, ulen; 3750 size_t len; 3751 int err; 3752 3753 ulen = *ulenp; 3754 if (!ulen ^ !uname) 3755 return -EINVAL; 3756 3757 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, 3758 probe_offset, probe_addr, missed); 3759 if (err) 3760 return err; 3761 3762 if (buf) { 3763 len = strlen(buf); 3764 *ulenp = len + 1; 3765 } else { 3766 *ulenp = 1; 3767 } 3768 if (!uname) 3769 return 0; 3770 3771 if (buf) { 3772 err = bpf_copy_to_user(uname, buf, ulen, len); 3773 if (err) 3774 return err; 3775 } else { 3776 char zero = '\0'; 3777 3778 if (put_user(zero, uname)) 3779 return -EFAULT; 3780 } 3781 return 0; 3782 } 3783 3784 #ifdef CONFIG_KPROBE_EVENTS 3785 static int bpf_perf_link_fill_kprobe(const struct perf_event *event, 3786 struct bpf_link_info *info) 3787 { 3788 unsigned long missed; 3789 char __user *uname; 3790 u64 addr, offset; 3791 u32 ulen, type; 3792 int err; 3793 3794 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); 3795 ulen = info->perf_event.kprobe.name_len; 3796 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr, 3797 &type, &missed); 3798 if (err) 3799 return err; 3800 if (type == BPF_FD_TYPE_KRETPROBE) 3801 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; 3802 else 3803 info->perf_event.type = BPF_PERF_EVENT_KPROBE; 3804 info->perf_event.kprobe.name_len = ulen; 3805 info->perf_event.kprobe.offset = offset; 3806 info->perf_event.kprobe.missed = missed; 3807 if (!kallsyms_show_value(current_cred())) 3808 addr = 0; 3809 info->perf_event.kprobe.addr = addr; 3810 info->perf_event.kprobe.cookie = event->bpf_cookie; 3811 return 0; 3812 } 3813 3814 static void bpf_perf_link_fdinfo_kprobe(const struct perf_event *event, 3815 struct seq_file *seq) 3816 { 3817 const char *name; 3818 int err; 3819 u32 prog_id, type; 3820 u64 offset, addr; 3821 unsigned long missed; 3822 3823 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 3824 &offset, &addr, &missed); 3825 if (err) 3826 return; 3827 3828 seq_printf(seq, 3829 "name:\t%s\n" 3830 "offset:\t%#llx\n" 3831 "missed:\t%lu\n" 3832 "addr:\t%#llx\n" 3833 "event_type:\t%s\n" 3834 "cookie:\t%llu\n", 3835 name, offset, missed, addr, 3836 type == BPF_FD_TYPE_KRETPROBE ? "kretprobe" : "kprobe", 3837 event->bpf_cookie); 3838 } 3839 #endif 3840 3841 #ifdef CONFIG_UPROBE_EVENTS 3842 static int bpf_perf_link_fill_uprobe(const struct perf_event *event, 3843 struct bpf_link_info *info) 3844 { 3845 u64 ref_ctr_offset, offset; 3846 char __user *uname; 3847 u32 ulen, type; 3848 int err; 3849 3850 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); 3851 ulen = info->perf_event.uprobe.name_len; 3852 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &ref_ctr_offset, 3853 &type, NULL); 3854 if (err) 3855 return err; 3856 3857 if (type == BPF_FD_TYPE_URETPROBE) 3858 info->perf_event.type = BPF_PERF_EVENT_URETPROBE; 3859 else 3860 info->perf_event.type = BPF_PERF_EVENT_UPROBE; 3861 info->perf_event.uprobe.name_len = ulen; 3862 info->perf_event.uprobe.offset = offset; 3863 info->perf_event.uprobe.cookie = event->bpf_cookie; 3864 info->perf_event.uprobe.ref_ctr_offset = ref_ctr_offset; 3865 return 0; 3866 } 3867 3868 static void bpf_perf_link_fdinfo_uprobe(const struct perf_event *event, 3869 struct seq_file *seq) 3870 { 3871 const char *name; 3872 int err; 3873 u32 prog_id, type; 3874 u64 offset, ref_ctr_offset; 3875 unsigned long missed; 3876 3877 err = bpf_get_perf_event_info(event, &prog_id, &type, &name, 3878 &offset, &ref_ctr_offset, &missed); 3879 if (err) 3880 return; 3881 3882 seq_printf(seq, 3883 "name:\t%s\n" 3884 "offset:\t%#llx\n" 3885 "ref_ctr_offset:\t%#llx\n" 3886 "event_type:\t%s\n" 3887 "cookie:\t%llu\n", 3888 name, offset, ref_ctr_offset, 3889 type == BPF_FD_TYPE_URETPROBE ? "uretprobe" : "uprobe", 3890 event->bpf_cookie); 3891 } 3892 #endif 3893 3894 static int bpf_perf_link_fill_probe(const struct perf_event *event, 3895 struct bpf_link_info *info) 3896 { 3897 #ifdef CONFIG_KPROBE_EVENTS 3898 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 3899 return bpf_perf_link_fill_kprobe(event, info); 3900 #endif 3901 #ifdef CONFIG_UPROBE_EVENTS 3902 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 3903 return bpf_perf_link_fill_uprobe(event, info); 3904 #endif 3905 return -EOPNOTSUPP; 3906 } 3907 3908 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, 3909 struct bpf_link_info *info) 3910 { 3911 char __user *uname; 3912 u32 ulen; 3913 int err; 3914 3915 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); 3916 ulen = info->perf_event.tracepoint.name_len; 3917 err = bpf_perf_link_fill_common(event, uname, &ulen, NULL, NULL, NULL, NULL); 3918 if (err) 3919 return err; 3920 3921 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; 3922 info->perf_event.tracepoint.name_len = ulen; 3923 info->perf_event.tracepoint.cookie = event->bpf_cookie; 3924 return 0; 3925 } 3926 3927 static int bpf_perf_link_fill_perf_event(const struct perf_event *event, 3928 struct bpf_link_info *info) 3929 { 3930 info->perf_event.event.type = event->attr.type; 3931 info->perf_event.event.config = event->attr.config; 3932 info->perf_event.event.cookie = event->bpf_cookie; 3933 info->perf_event.type = BPF_PERF_EVENT_EVENT; 3934 return 0; 3935 } 3936 3937 static int bpf_perf_link_fill_link_info(const struct bpf_link *link, 3938 struct bpf_link_info *info) 3939 { 3940 struct bpf_perf_link *perf_link; 3941 const struct perf_event *event; 3942 3943 perf_link = container_of(link, struct bpf_perf_link, link); 3944 event = perf_get_event(perf_link->perf_file); 3945 if (IS_ERR(event)) 3946 return PTR_ERR(event); 3947 3948 switch (event->prog->type) { 3949 case BPF_PROG_TYPE_PERF_EVENT: 3950 return bpf_perf_link_fill_perf_event(event, info); 3951 case BPF_PROG_TYPE_TRACEPOINT: 3952 return bpf_perf_link_fill_tracepoint(event, info); 3953 case BPF_PROG_TYPE_KPROBE: 3954 return bpf_perf_link_fill_probe(event, info); 3955 default: 3956 return -EOPNOTSUPP; 3957 } 3958 } 3959 3960 static void bpf_perf_event_link_show_fdinfo(const struct perf_event *event, 3961 struct seq_file *seq) 3962 { 3963 seq_printf(seq, 3964 "type:\t%u\n" 3965 "config:\t%llu\n" 3966 "event_type:\t%s\n" 3967 "cookie:\t%llu\n", 3968 event->attr.type, event->attr.config, 3969 "event", event->bpf_cookie); 3970 } 3971 3972 static void bpf_tracepoint_link_show_fdinfo(const struct perf_event *event, 3973 struct seq_file *seq) 3974 { 3975 int err; 3976 const char *name; 3977 u32 prog_id; 3978 3979 err = bpf_get_perf_event_info(event, &prog_id, NULL, &name, NULL, 3980 NULL, NULL); 3981 if (err) 3982 return; 3983 3984 seq_printf(seq, 3985 "tp_name:\t%s\n" 3986 "event_type:\t%s\n" 3987 "cookie:\t%llu\n", 3988 name, "tracepoint", event->bpf_cookie); 3989 } 3990 3991 static void bpf_probe_link_show_fdinfo(const struct perf_event *event, 3992 struct seq_file *seq) 3993 { 3994 #ifdef CONFIG_KPROBE_EVENTS 3995 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) 3996 return bpf_perf_link_fdinfo_kprobe(event, seq); 3997 #endif 3998 3999 #ifdef CONFIG_UPROBE_EVENTS 4000 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) 4001 return bpf_perf_link_fdinfo_uprobe(event, seq); 4002 #endif 4003 } 4004 4005 static void bpf_perf_link_show_fdinfo(const struct bpf_link *link, 4006 struct seq_file *seq) 4007 { 4008 struct bpf_perf_link *perf_link; 4009 const struct perf_event *event; 4010 4011 perf_link = container_of(link, struct bpf_perf_link, link); 4012 event = perf_get_event(perf_link->perf_file); 4013 if (IS_ERR(event)) 4014 return; 4015 4016 switch (event->prog->type) { 4017 case BPF_PROG_TYPE_PERF_EVENT: 4018 return bpf_perf_event_link_show_fdinfo(event, seq); 4019 case BPF_PROG_TYPE_TRACEPOINT: 4020 return bpf_tracepoint_link_show_fdinfo(event, seq); 4021 case BPF_PROG_TYPE_KPROBE: 4022 return bpf_probe_link_show_fdinfo(event, seq); 4023 default: 4024 return; 4025 } 4026 } 4027 4028 static const struct bpf_link_ops bpf_perf_link_lops = { 4029 .release = bpf_perf_link_release, 4030 .dealloc = bpf_perf_link_dealloc, 4031 .fill_link_info = bpf_perf_link_fill_link_info, 4032 .show_fdinfo = bpf_perf_link_show_fdinfo, 4033 }; 4034 4035 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4036 { 4037 struct bpf_link_primer link_primer; 4038 struct bpf_perf_link *link; 4039 struct perf_event *event; 4040 struct file *perf_file; 4041 int err; 4042 4043 if (attr->link_create.flags) 4044 return -EINVAL; 4045 4046 perf_file = perf_event_get(attr->link_create.target_fd); 4047 if (IS_ERR(perf_file)) 4048 return PTR_ERR(perf_file); 4049 4050 link = kzalloc(sizeof(*link), GFP_USER); 4051 if (!link) { 4052 err = -ENOMEM; 4053 goto out_put_file; 4054 } 4055 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog, 4056 attr->link_create.attach_type); 4057 link->perf_file = perf_file; 4058 4059 err = bpf_link_prime(&link->link, &link_primer); 4060 if (err) { 4061 kfree(link); 4062 goto out_put_file; 4063 } 4064 4065 event = perf_file->private_data; 4066 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); 4067 if (err) { 4068 bpf_link_cleanup(&link_primer); 4069 goto out_put_file; 4070 } 4071 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ 4072 bpf_prog_inc(prog); 4073 4074 return bpf_link_settle(&link_primer); 4075 4076 out_put_file: 4077 fput(perf_file); 4078 return err; 4079 } 4080 #else 4081 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 4082 { 4083 return -EOPNOTSUPP; 4084 } 4085 #endif /* CONFIG_PERF_EVENTS */ 4086 4087 static int bpf_raw_tp_link_attach(struct bpf_prog *prog, 4088 const char __user *user_tp_name, u64 cookie, 4089 enum bpf_attach_type attach_type) 4090 { 4091 struct bpf_link_primer link_primer; 4092 struct bpf_raw_tp_link *link; 4093 struct bpf_raw_event_map *btp; 4094 const char *tp_name; 4095 char buf[128]; 4096 int err; 4097 4098 switch (prog->type) { 4099 case BPF_PROG_TYPE_TRACING: 4100 case BPF_PROG_TYPE_EXT: 4101 case BPF_PROG_TYPE_LSM: 4102 if (user_tp_name) 4103 /* The attach point for this category of programs 4104 * should be specified via btf_id during program load. 4105 */ 4106 return -EINVAL; 4107 if (prog->type == BPF_PROG_TYPE_TRACING && 4108 prog->expected_attach_type == BPF_TRACE_RAW_TP) { 4109 tp_name = prog->aux->attach_func_name; 4110 break; 4111 } 4112 return bpf_tracing_prog_attach(prog, 0, 0, 0, attach_type); 4113 case BPF_PROG_TYPE_RAW_TRACEPOINT: 4114 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: 4115 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) 4116 return -EFAULT; 4117 buf[sizeof(buf) - 1] = 0; 4118 tp_name = buf; 4119 break; 4120 default: 4121 return -EINVAL; 4122 } 4123 4124 btp = bpf_get_raw_tracepoint(tp_name); 4125 if (!btp) 4126 return -ENOENT; 4127 4128 link = kzalloc(sizeof(*link), GFP_USER); 4129 if (!link) { 4130 err = -ENOMEM; 4131 goto out_put_btp; 4132 } 4133 bpf_link_init_sleepable(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, 4134 &bpf_raw_tp_link_lops, prog, attach_type, 4135 tracepoint_is_faultable(btp->tp)); 4136 link->btp = btp; 4137 link->cookie = cookie; 4138 4139 err = bpf_link_prime(&link->link, &link_primer); 4140 if (err) { 4141 kfree(link); 4142 goto out_put_btp; 4143 } 4144 4145 err = bpf_probe_register(link->btp, link); 4146 if (err) { 4147 bpf_link_cleanup(&link_primer); 4148 goto out_put_btp; 4149 } 4150 4151 return bpf_link_settle(&link_primer); 4152 4153 out_put_btp: 4154 bpf_put_raw_tracepoint(btp); 4155 return err; 4156 } 4157 4158 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie 4159 4160 static int bpf_raw_tracepoint_open(const union bpf_attr *attr) 4161 { 4162 struct bpf_prog *prog; 4163 void __user *tp_name; 4164 __u64 cookie; 4165 int fd; 4166 4167 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) 4168 return -EINVAL; 4169 4170 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); 4171 if (IS_ERR(prog)) 4172 return PTR_ERR(prog); 4173 4174 tp_name = u64_to_user_ptr(attr->raw_tracepoint.name); 4175 cookie = attr->raw_tracepoint.cookie; 4176 fd = bpf_raw_tp_link_attach(prog, tp_name, cookie, prog->expected_attach_type); 4177 if (fd < 0) 4178 bpf_prog_put(prog); 4179 return fd; 4180 } 4181 4182 static enum bpf_prog_type 4183 attach_type_to_prog_type(enum bpf_attach_type attach_type) 4184 { 4185 switch (attach_type) { 4186 case BPF_CGROUP_INET_INGRESS: 4187 case BPF_CGROUP_INET_EGRESS: 4188 return BPF_PROG_TYPE_CGROUP_SKB; 4189 case BPF_CGROUP_INET_SOCK_CREATE: 4190 case BPF_CGROUP_INET_SOCK_RELEASE: 4191 case BPF_CGROUP_INET4_POST_BIND: 4192 case BPF_CGROUP_INET6_POST_BIND: 4193 return BPF_PROG_TYPE_CGROUP_SOCK; 4194 case BPF_CGROUP_INET4_BIND: 4195 case BPF_CGROUP_INET6_BIND: 4196 case BPF_CGROUP_INET4_CONNECT: 4197 case BPF_CGROUP_INET6_CONNECT: 4198 case BPF_CGROUP_UNIX_CONNECT: 4199 case BPF_CGROUP_INET4_GETPEERNAME: 4200 case BPF_CGROUP_INET6_GETPEERNAME: 4201 case BPF_CGROUP_UNIX_GETPEERNAME: 4202 case BPF_CGROUP_INET4_GETSOCKNAME: 4203 case BPF_CGROUP_INET6_GETSOCKNAME: 4204 case BPF_CGROUP_UNIX_GETSOCKNAME: 4205 case BPF_CGROUP_UDP4_SENDMSG: 4206 case BPF_CGROUP_UDP6_SENDMSG: 4207 case BPF_CGROUP_UNIX_SENDMSG: 4208 case BPF_CGROUP_UDP4_RECVMSG: 4209 case BPF_CGROUP_UDP6_RECVMSG: 4210 case BPF_CGROUP_UNIX_RECVMSG: 4211 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; 4212 case BPF_CGROUP_SOCK_OPS: 4213 return BPF_PROG_TYPE_SOCK_OPS; 4214 case BPF_CGROUP_DEVICE: 4215 return BPF_PROG_TYPE_CGROUP_DEVICE; 4216 case BPF_SK_MSG_VERDICT: 4217 return BPF_PROG_TYPE_SK_MSG; 4218 case BPF_SK_SKB_STREAM_PARSER: 4219 case BPF_SK_SKB_STREAM_VERDICT: 4220 case BPF_SK_SKB_VERDICT: 4221 return BPF_PROG_TYPE_SK_SKB; 4222 case BPF_LIRC_MODE2: 4223 return BPF_PROG_TYPE_LIRC_MODE2; 4224 case BPF_FLOW_DISSECTOR: 4225 return BPF_PROG_TYPE_FLOW_DISSECTOR; 4226 case BPF_CGROUP_SYSCTL: 4227 return BPF_PROG_TYPE_CGROUP_SYSCTL; 4228 case BPF_CGROUP_GETSOCKOPT: 4229 case BPF_CGROUP_SETSOCKOPT: 4230 return BPF_PROG_TYPE_CGROUP_SOCKOPT; 4231 case BPF_TRACE_ITER: 4232 case BPF_TRACE_RAW_TP: 4233 case BPF_TRACE_FENTRY: 4234 case BPF_TRACE_FEXIT: 4235 case BPF_MODIFY_RETURN: 4236 return BPF_PROG_TYPE_TRACING; 4237 case BPF_LSM_MAC: 4238 return BPF_PROG_TYPE_LSM; 4239 case BPF_SK_LOOKUP: 4240 return BPF_PROG_TYPE_SK_LOOKUP; 4241 case BPF_XDP: 4242 return BPF_PROG_TYPE_XDP; 4243 case BPF_LSM_CGROUP: 4244 return BPF_PROG_TYPE_LSM; 4245 case BPF_TCX_INGRESS: 4246 case BPF_TCX_EGRESS: 4247 case BPF_NETKIT_PRIMARY: 4248 case BPF_NETKIT_PEER: 4249 return BPF_PROG_TYPE_SCHED_CLS; 4250 default: 4251 return BPF_PROG_TYPE_UNSPEC; 4252 } 4253 } 4254 4255 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 4256 enum bpf_attach_type attach_type) 4257 { 4258 enum bpf_prog_type ptype; 4259 4260 switch (prog->type) { 4261 case BPF_PROG_TYPE_CGROUP_SOCK: 4262 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4263 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4264 case BPF_PROG_TYPE_SK_LOOKUP: 4265 return attach_type == prog->expected_attach_type ? 0 : -EINVAL; 4266 case BPF_PROG_TYPE_CGROUP_SKB: 4267 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) 4268 /* cg-skb progs can be loaded by unpriv user. 4269 * check permissions at attach time. 4270 */ 4271 return -EPERM; 4272 4273 ptype = attach_type_to_prog_type(attach_type); 4274 if (prog->type != ptype) 4275 return -EINVAL; 4276 4277 return prog->enforce_expected_attach_type && 4278 prog->expected_attach_type != attach_type ? 4279 -EINVAL : 0; 4280 case BPF_PROG_TYPE_EXT: 4281 return 0; 4282 case BPF_PROG_TYPE_NETFILTER: 4283 if (attach_type != BPF_NETFILTER) 4284 return -EINVAL; 4285 return 0; 4286 case BPF_PROG_TYPE_PERF_EVENT: 4287 case BPF_PROG_TYPE_TRACEPOINT: 4288 if (attach_type != BPF_PERF_EVENT) 4289 return -EINVAL; 4290 return 0; 4291 case BPF_PROG_TYPE_KPROBE: 4292 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && 4293 attach_type != BPF_TRACE_KPROBE_MULTI) 4294 return -EINVAL; 4295 if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION && 4296 attach_type != BPF_TRACE_KPROBE_SESSION) 4297 return -EINVAL; 4298 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && 4299 attach_type != BPF_TRACE_UPROBE_MULTI) 4300 return -EINVAL; 4301 if (prog->expected_attach_type == BPF_TRACE_UPROBE_SESSION && 4302 attach_type != BPF_TRACE_UPROBE_SESSION) 4303 return -EINVAL; 4304 if (attach_type != BPF_PERF_EVENT && 4305 attach_type != BPF_TRACE_KPROBE_MULTI && 4306 attach_type != BPF_TRACE_KPROBE_SESSION && 4307 attach_type != BPF_TRACE_UPROBE_MULTI && 4308 attach_type != BPF_TRACE_UPROBE_SESSION) 4309 return -EINVAL; 4310 return 0; 4311 case BPF_PROG_TYPE_SCHED_CLS: 4312 if (attach_type != BPF_TCX_INGRESS && 4313 attach_type != BPF_TCX_EGRESS && 4314 attach_type != BPF_NETKIT_PRIMARY && 4315 attach_type != BPF_NETKIT_PEER) 4316 return -EINVAL; 4317 return 0; 4318 default: 4319 ptype = attach_type_to_prog_type(attach_type); 4320 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) 4321 return -EINVAL; 4322 return 0; 4323 } 4324 } 4325 4326 static bool is_cgroup_prog_type(enum bpf_prog_type ptype, enum bpf_attach_type atype, 4327 bool check_atype) 4328 { 4329 switch (ptype) { 4330 case BPF_PROG_TYPE_CGROUP_DEVICE: 4331 case BPF_PROG_TYPE_CGROUP_SKB: 4332 case BPF_PROG_TYPE_CGROUP_SOCK: 4333 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4334 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4335 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4336 case BPF_PROG_TYPE_SOCK_OPS: 4337 return true; 4338 case BPF_PROG_TYPE_LSM: 4339 return check_atype ? atype == BPF_LSM_CGROUP : true; 4340 default: 4341 return false; 4342 } 4343 } 4344 4345 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision 4346 4347 #define BPF_F_ATTACH_MASK_BASE \ 4348 (BPF_F_ALLOW_OVERRIDE | \ 4349 BPF_F_ALLOW_MULTI | \ 4350 BPF_F_REPLACE | \ 4351 BPF_F_PREORDER) 4352 4353 #define BPF_F_ATTACH_MASK_MPROG \ 4354 (BPF_F_REPLACE | \ 4355 BPF_F_BEFORE | \ 4356 BPF_F_AFTER | \ 4357 BPF_F_ID | \ 4358 BPF_F_LINK) 4359 4360 static int bpf_prog_attach(const union bpf_attr *attr) 4361 { 4362 enum bpf_prog_type ptype; 4363 struct bpf_prog *prog; 4364 int ret; 4365 4366 if (CHECK_ATTR(BPF_PROG_ATTACH)) 4367 return -EINVAL; 4368 4369 ptype = attach_type_to_prog_type(attr->attach_type); 4370 if (ptype == BPF_PROG_TYPE_UNSPEC) 4371 return -EINVAL; 4372 if (bpf_mprog_supported(ptype)) { 4373 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4374 return -EINVAL; 4375 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4376 if (attr->attach_flags & ~(BPF_F_ATTACH_MASK_BASE | BPF_F_ATTACH_MASK_MPROG)) 4377 return -EINVAL; 4378 } else { 4379 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) 4380 return -EINVAL; 4381 if (attr->relative_fd || 4382 attr->expected_revision) 4383 return -EINVAL; 4384 } 4385 4386 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4387 if (IS_ERR(prog)) 4388 return PTR_ERR(prog); 4389 4390 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { 4391 bpf_prog_put(prog); 4392 return -EINVAL; 4393 } 4394 4395 if (is_cgroup_prog_type(ptype, prog->expected_attach_type, true)) { 4396 ret = cgroup_bpf_prog_attach(attr, ptype, prog); 4397 goto out; 4398 } 4399 4400 switch (ptype) { 4401 case BPF_PROG_TYPE_SK_SKB: 4402 case BPF_PROG_TYPE_SK_MSG: 4403 ret = sock_map_get_from_fd(attr, prog); 4404 break; 4405 case BPF_PROG_TYPE_LIRC_MODE2: 4406 ret = lirc_prog_attach(attr, prog); 4407 break; 4408 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4409 ret = netns_bpf_prog_attach(attr, prog); 4410 break; 4411 case BPF_PROG_TYPE_SCHED_CLS: 4412 if (attr->attach_type == BPF_TCX_INGRESS || 4413 attr->attach_type == BPF_TCX_EGRESS) 4414 ret = tcx_prog_attach(attr, prog); 4415 else 4416 ret = netkit_prog_attach(attr, prog); 4417 break; 4418 default: 4419 ret = -EINVAL; 4420 } 4421 out: 4422 if (ret) 4423 bpf_prog_put(prog); 4424 return ret; 4425 } 4426 4427 #define BPF_PROG_DETACH_LAST_FIELD expected_revision 4428 4429 static int bpf_prog_detach(const union bpf_attr *attr) 4430 { 4431 struct bpf_prog *prog = NULL; 4432 enum bpf_prog_type ptype; 4433 int ret; 4434 4435 if (CHECK_ATTR(BPF_PROG_DETACH)) 4436 return -EINVAL; 4437 4438 ptype = attach_type_to_prog_type(attr->attach_type); 4439 if (bpf_mprog_supported(ptype)) { 4440 if (ptype == BPF_PROG_TYPE_UNSPEC) 4441 return -EINVAL; 4442 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) 4443 return -EINVAL; 4444 if (attr->attach_bpf_fd) { 4445 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); 4446 if (IS_ERR(prog)) 4447 return PTR_ERR(prog); 4448 } 4449 } else if (is_cgroup_prog_type(ptype, 0, false)) { 4450 if (attr->attach_flags || attr->relative_fd) 4451 return -EINVAL; 4452 } else if (attr->attach_flags || 4453 attr->relative_fd || 4454 attr->expected_revision) { 4455 return -EINVAL; 4456 } 4457 4458 switch (ptype) { 4459 case BPF_PROG_TYPE_SK_MSG: 4460 case BPF_PROG_TYPE_SK_SKB: 4461 ret = sock_map_prog_detach(attr, ptype); 4462 break; 4463 case BPF_PROG_TYPE_LIRC_MODE2: 4464 ret = lirc_prog_detach(attr); 4465 break; 4466 case BPF_PROG_TYPE_FLOW_DISSECTOR: 4467 ret = netns_bpf_prog_detach(attr, ptype); 4468 break; 4469 case BPF_PROG_TYPE_CGROUP_DEVICE: 4470 case BPF_PROG_TYPE_CGROUP_SKB: 4471 case BPF_PROG_TYPE_CGROUP_SOCK: 4472 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 4473 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 4474 case BPF_PROG_TYPE_CGROUP_SYSCTL: 4475 case BPF_PROG_TYPE_SOCK_OPS: 4476 case BPF_PROG_TYPE_LSM: 4477 ret = cgroup_bpf_prog_detach(attr, ptype); 4478 break; 4479 case BPF_PROG_TYPE_SCHED_CLS: 4480 if (attr->attach_type == BPF_TCX_INGRESS || 4481 attr->attach_type == BPF_TCX_EGRESS) 4482 ret = tcx_prog_detach(attr, prog); 4483 else 4484 ret = netkit_prog_detach(attr, prog); 4485 break; 4486 default: 4487 ret = -EINVAL; 4488 } 4489 4490 if (prog) 4491 bpf_prog_put(prog); 4492 return ret; 4493 } 4494 4495 #define BPF_PROG_QUERY_LAST_FIELD query.revision 4496 4497 static int bpf_prog_query(const union bpf_attr *attr, 4498 union bpf_attr __user *uattr) 4499 { 4500 if (!bpf_net_capable()) 4501 return -EPERM; 4502 if (CHECK_ATTR(BPF_PROG_QUERY)) 4503 return -EINVAL; 4504 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) 4505 return -EINVAL; 4506 4507 switch (attr->query.attach_type) { 4508 case BPF_CGROUP_INET_INGRESS: 4509 case BPF_CGROUP_INET_EGRESS: 4510 case BPF_CGROUP_INET_SOCK_CREATE: 4511 case BPF_CGROUP_INET_SOCK_RELEASE: 4512 case BPF_CGROUP_INET4_BIND: 4513 case BPF_CGROUP_INET6_BIND: 4514 case BPF_CGROUP_INET4_POST_BIND: 4515 case BPF_CGROUP_INET6_POST_BIND: 4516 case BPF_CGROUP_INET4_CONNECT: 4517 case BPF_CGROUP_INET6_CONNECT: 4518 case BPF_CGROUP_UNIX_CONNECT: 4519 case BPF_CGROUP_INET4_GETPEERNAME: 4520 case BPF_CGROUP_INET6_GETPEERNAME: 4521 case BPF_CGROUP_UNIX_GETPEERNAME: 4522 case BPF_CGROUP_INET4_GETSOCKNAME: 4523 case BPF_CGROUP_INET6_GETSOCKNAME: 4524 case BPF_CGROUP_UNIX_GETSOCKNAME: 4525 case BPF_CGROUP_UDP4_SENDMSG: 4526 case BPF_CGROUP_UDP6_SENDMSG: 4527 case BPF_CGROUP_UNIX_SENDMSG: 4528 case BPF_CGROUP_UDP4_RECVMSG: 4529 case BPF_CGROUP_UDP6_RECVMSG: 4530 case BPF_CGROUP_UNIX_RECVMSG: 4531 case BPF_CGROUP_SOCK_OPS: 4532 case BPF_CGROUP_DEVICE: 4533 case BPF_CGROUP_SYSCTL: 4534 case BPF_CGROUP_GETSOCKOPT: 4535 case BPF_CGROUP_SETSOCKOPT: 4536 case BPF_LSM_CGROUP: 4537 return cgroup_bpf_prog_query(attr, uattr); 4538 case BPF_LIRC_MODE2: 4539 return lirc_prog_query(attr, uattr); 4540 case BPF_FLOW_DISSECTOR: 4541 case BPF_SK_LOOKUP: 4542 return netns_bpf_prog_query(attr, uattr); 4543 case BPF_SK_SKB_STREAM_PARSER: 4544 case BPF_SK_SKB_STREAM_VERDICT: 4545 case BPF_SK_MSG_VERDICT: 4546 case BPF_SK_SKB_VERDICT: 4547 return sock_map_bpf_prog_query(attr, uattr); 4548 case BPF_TCX_INGRESS: 4549 case BPF_TCX_EGRESS: 4550 return tcx_prog_query(attr, uattr); 4551 case BPF_NETKIT_PRIMARY: 4552 case BPF_NETKIT_PEER: 4553 return netkit_prog_query(attr, uattr); 4554 default: 4555 return -EINVAL; 4556 } 4557 } 4558 4559 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size 4560 4561 static int bpf_prog_test_run(const union bpf_attr *attr, 4562 union bpf_attr __user *uattr) 4563 { 4564 struct bpf_prog *prog; 4565 int ret = -ENOTSUPP; 4566 4567 if (CHECK_ATTR(BPF_PROG_TEST_RUN)) 4568 return -EINVAL; 4569 4570 if ((attr->test.ctx_size_in && !attr->test.ctx_in) || 4571 (!attr->test.ctx_size_in && attr->test.ctx_in)) 4572 return -EINVAL; 4573 4574 if ((attr->test.ctx_size_out && !attr->test.ctx_out) || 4575 (!attr->test.ctx_size_out && attr->test.ctx_out)) 4576 return -EINVAL; 4577 4578 prog = bpf_prog_get(attr->test.prog_fd); 4579 if (IS_ERR(prog)) 4580 return PTR_ERR(prog); 4581 4582 if (prog->aux->ops->test_run) 4583 ret = prog->aux->ops->test_run(prog, attr, uattr); 4584 4585 bpf_prog_put(prog); 4586 return ret; 4587 } 4588 4589 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id 4590 4591 static int bpf_obj_get_next_id(const union bpf_attr *attr, 4592 union bpf_attr __user *uattr, 4593 struct idr *idr, 4594 spinlock_t *lock) 4595 { 4596 u32 next_id = attr->start_id; 4597 int err = 0; 4598 4599 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) 4600 return -EINVAL; 4601 4602 if (!capable(CAP_SYS_ADMIN)) 4603 return -EPERM; 4604 4605 next_id++; 4606 spin_lock_bh(lock); 4607 if (!idr_get_next(idr, &next_id)) 4608 err = -ENOENT; 4609 spin_unlock_bh(lock); 4610 4611 if (!err) 4612 err = put_user(next_id, &uattr->next_id); 4613 4614 return err; 4615 } 4616 4617 struct bpf_map *bpf_map_get_curr_or_next(u32 *id) 4618 { 4619 struct bpf_map *map; 4620 4621 spin_lock_bh(&map_idr_lock); 4622 again: 4623 map = idr_get_next(&map_idr, id); 4624 if (map) { 4625 map = __bpf_map_inc_not_zero(map, false); 4626 if (IS_ERR(map)) { 4627 (*id)++; 4628 goto again; 4629 } 4630 } 4631 spin_unlock_bh(&map_idr_lock); 4632 4633 return map; 4634 } 4635 4636 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) 4637 { 4638 struct bpf_prog *prog; 4639 4640 spin_lock_bh(&prog_idr_lock); 4641 again: 4642 prog = idr_get_next(&prog_idr, id); 4643 if (prog) { 4644 prog = bpf_prog_inc_not_zero(prog); 4645 if (IS_ERR(prog)) { 4646 (*id)++; 4647 goto again; 4648 } 4649 } 4650 spin_unlock_bh(&prog_idr_lock); 4651 4652 return prog; 4653 } 4654 4655 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id 4656 4657 struct bpf_prog *bpf_prog_by_id(u32 id) 4658 { 4659 struct bpf_prog *prog; 4660 4661 if (!id) 4662 return ERR_PTR(-ENOENT); 4663 4664 spin_lock_bh(&prog_idr_lock); 4665 prog = idr_find(&prog_idr, id); 4666 if (prog) 4667 prog = bpf_prog_inc_not_zero(prog); 4668 else 4669 prog = ERR_PTR(-ENOENT); 4670 spin_unlock_bh(&prog_idr_lock); 4671 return prog; 4672 } 4673 4674 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) 4675 { 4676 struct bpf_prog *prog; 4677 u32 id = attr->prog_id; 4678 int fd; 4679 4680 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) 4681 return -EINVAL; 4682 4683 if (!capable(CAP_SYS_ADMIN)) 4684 return -EPERM; 4685 4686 prog = bpf_prog_by_id(id); 4687 if (IS_ERR(prog)) 4688 return PTR_ERR(prog); 4689 4690 fd = bpf_prog_new_fd(prog); 4691 if (fd < 0) 4692 bpf_prog_put(prog); 4693 4694 return fd; 4695 } 4696 4697 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags 4698 4699 static int bpf_map_get_fd_by_id(const union bpf_attr *attr) 4700 { 4701 struct bpf_map *map; 4702 u32 id = attr->map_id; 4703 int f_flags; 4704 int fd; 4705 4706 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || 4707 attr->open_flags & ~BPF_OBJ_FLAG_MASK) 4708 return -EINVAL; 4709 4710 if (!capable(CAP_SYS_ADMIN)) 4711 return -EPERM; 4712 4713 f_flags = bpf_get_file_flag(attr->open_flags); 4714 if (f_flags < 0) 4715 return f_flags; 4716 4717 spin_lock_bh(&map_idr_lock); 4718 map = idr_find(&map_idr, id); 4719 if (map) 4720 map = __bpf_map_inc_not_zero(map, true); 4721 else 4722 map = ERR_PTR(-ENOENT); 4723 spin_unlock_bh(&map_idr_lock); 4724 4725 if (IS_ERR(map)) 4726 return PTR_ERR(map); 4727 4728 fd = bpf_map_new_fd(map, f_flags); 4729 if (fd < 0) 4730 bpf_map_put_with_uref(map); 4731 4732 return fd; 4733 } 4734 4735 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, 4736 unsigned long addr, u32 *off, 4737 u32 *type) 4738 { 4739 const struct bpf_map *map; 4740 int i; 4741 4742 mutex_lock(&prog->aux->used_maps_mutex); 4743 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { 4744 map = prog->aux->used_maps[i]; 4745 if (map == (void *)addr) { 4746 *type = BPF_PSEUDO_MAP_FD; 4747 goto out; 4748 } 4749 if (!map->ops->map_direct_value_meta) 4750 continue; 4751 if (!map->ops->map_direct_value_meta(map, addr, off)) { 4752 *type = BPF_PSEUDO_MAP_VALUE; 4753 goto out; 4754 } 4755 } 4756 map = NULL; 4757 4758 out: 4759 mutex_unlock(&prog->aux->used_maps_mutex); 4760 return map; 4761 } 4762 4763 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, 4764 const struct cred *f_cred) 4765 { 4766 const struct bpf_map *map; 4767 struct bpf_insn *insns; 4768 u32 off, type; 4769 u64 imm; 4770 u8 code; 4771 int i; 4772 4773 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), 4774 GFP_USER); 4775 if (!insns) 4776 return insns; 4777 4778 for (i = 0; i < prog->len; i++) { 4779 code = insns[i].code; 4780 4781 if (code == (BPF_JMP | BPF_TAIL_CALL)) { 4782 insns[i].code = BPF_JMP | BPF_CALL; 4783 insns[i].imm = BPF_FUNC_tail_call; 4784 /* fall-through */ 4785 } 4786 if (code == (BPF_JMP | BPF_CALL) || 4787 code == (BPF_JMP | BPF_CALL_ARGS)) { 4788 if (code == (BPF_JMP | BPF_CALL_ARGS)) 4789 insns[i].code = BPF_JMP | BPF_CALL; 4790 if (!bpf_dump_raw_ok(f_cred)) 4791 insns[i].imm = 0; 4792 continue; 4793 } 4794 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { 4795 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; 4796 continue; 4797 } 4798 4799 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || 4800 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { 4801 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; 4802 continue; 4803 } 4804 4805 if (code != (BPF_LD | BPF_IMM | BPF_DW)) 4806 continue; 4807 4808 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; 4809 map = bpf_map_from_imm(prog, imm, &off, &type); 4810 if (map) { 4811 insns[i].src_reg = type; 4812 insns[i].imm = map->id; 4813 insns[i + 1].imm = off; 4814 continue; 4815 } 4816 } 4817 4818 return insns; 4819 } 4820 4821 static int set_info_rec_size(struct bpf_prog_info *info) 4822 { 4823 /* 4824 * Ensure info.*_rec_size is the same as kernel expected size 4825 * 4826 * or 4827 * 4828 * Only allow zero *_rec_size if both _rec_size and _cnt are 4829 * zero. In this case, the kernel will set the expected 4830 * _rec_size back to the info. 4831 */ 4832 4833 if ((info->nr_func_info || info->func_info_rec_size) && 4834 info->func_info_rec_size != sizeof(struct bpf_func_info)) 4835 return -EINVAL; 4836 4837 if ((info->nr_line_info || info->line_info_rec_size) && 4838 info->line_info_rec_size != sizeof(struct bpf_line_info)) 4839 return -EINVAL; 4840 4841 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && 4842 info->jited_line_info_rec_size != sizeof(__u64)) 4843 return -EINVAL; 4844 4845 info->func_info_rec_size = sizeof(struct bpf_func_info); 4846 info->line_info_rec_size = sizeof(struct bpf_line_info); 4847 info->jited_line_info_rec_size = sizeof(__u64); 4848 4849 return 0; 4850 } 4851 4852 static int bpf_prog_get_info_by_fd(struct file *file, 4853 struct bpf_prog *prog, 4854 const union bpf_attr *attr, 4855 union bpf_attr __user *uattr) 4856 { 4857 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 4858 struct btf *attach_btf = bpf_prog_get_target_btf(prog); 4859 struct bpf_prog_info info; 4860 u32 info_len = attr->info.info_len; 4861 struct bpf_prog_kstats stats; 4862 char __user *uinsns; 4863 u32 ulen; 4864 int err; 4865 4866 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 4867 if (err) 4868 return err; 4869 info_len = min_t(u32, sizeof(info), info_len); 4870 4871 memset(&info, 0, sizeof(info)); 4872 if (copy_from_user(&info, uinfo, info_len)) 4873 return -EFAULT; 4874 4875 info.type = prog->type; 4876 info.id = prog->aux->id; 4877 info.load_time = prog->aux->load_time; 4878 info.created_by_uid = from_kuid_munged(current_user_ns(), 4879 prog->aux->user->uid); 4880 info.gpl_compatible = prog->gpl_compatible; 4881 4882 memcpy(info.tag, prog->tag, sizeof(prog->tag)); 4883 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); 4884 4885 mutex_lock(&prog->aux->used_maps_mutex); 4886 ulen = info.nr_map_ids; 4887 info.nr_map_ids = prog->aux->used_map_cnt; 4888 ulen = min_t(u32, info.nr_map_ids, ulen); 4889 if (ulen) { 4890 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); 4891 u32 i; 4892 4893 for (i = 0; i < ulen; i++) 4894 if (put_user(prog->aux->used_maps[i]->id, 4895 &user_map_ids[i])) { 4896 mutex_unlock(&prog->aux->used_maps_mutex); 4897 return -EFAULT; 4898 } 4899 } 4900 mutex_unlock(&prog->aux->used_maps_mutex); 4901 4902 err = set_info_rec_size(&info); 4903 if (err) 4904 return err; 4905 4906 bpf_prog_get_stats(prog, &stats); 4907 info.run_time_ns = stats.nsecs; 4908 info.run_cnt = stats.cnt; 4909 info.recursion_misses = stats.misses; 4910 4911 info.verified_insns = prog->aux->verified_insns; 4912 if (prog->aux->btf) 4913 info.btf_id = btf_obj_id(prog->aux->btf); 4914 4915 if (!bpf_capable()) { 4916 info.jited_prog_len = 0; 4917 info.xlated_prog_len = 0; 4918 info.nr_jited_ksyms = 0; 4919 info.nr_jited_func_lens = 0; 4920 info.nr_func_info = 0; 4921 info.nr_line_info = 0; 4922 info.nr_jited_line_info = 0; 4923 goto done; 4924 } 4925 4926 ulen = info.xlated_prog_len; 4927 info.xlated_prog_len = bpf_prog_insn_size(prog); 4928 if (info.xlated_prog_len && ulen) { 4929 struct bpf_insn *insns_sanitized; 4930 bool fault; 4931 4932 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { 4933 info.xlated_prog_insns = 0; 4934 goto done; 4935 } 4936 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); 4937 if (!insns_sanitized) 4938 return -ENOMEM; 4939 uinsns = u64_to_user_ptr(info.xlated_prog_insns); 4940 ulen = min_t(u32, info.xlated_prog_len, ulen); 4941 fault = copy_to_user(uinsns, insns_sanitized, ulen); 4942 kfree(insns_sanitized); 4943 if (fault) 4944 return -EFAULT; 4945 } 4946 4947 if (bpf_prog_is_offloaded(prog->aux)) { 4948 err = bpf_prog_offload_info_fill(&info, prog); 4949 if (err) 4950 return err; 4951 goto done; 4952 } 4953 4954 /* NOTE: the following code is supposed to be skipped for offload. 4955 * bpf_prog_offload_info_fill() is the place to fill similar fields 4956 * for offload. 4957 */ 4958 ulen = info.jited_prog_len; 4959 if (prog->aux->func_cnt) { 4960 u32 i; 4961 4962 info.jited_prog_len = 0; 4963 for (i = 0; i < prog->aux->func_cnt; i++) 4964 info.jited_prog_len += prog->aux->func[i]->jited_len; 4965 } else { 4966 info.jited_prog_len = prog->jited_len; 4967 } 4968 4969 if (info.jited_prog_len && ulen) { 4970 if (bpf_dump_raw_ok(file->f_cred)) { 4971 uinsns = u64_to_user_ptr(info.jited_prog_insns); 4972 ulen = min_t(u32, info.jited_prog_len, ulen); 4973 4974 /* for multi-function programs, copy the JITed 4975 * instructions for all the functions 4976 */ 4977 if (prog->aux->func_cnt) { 4978 u32 len, free, i; 4979 u8 *img; 4980 4981 free = ulen; 4982 for (i = 0; i < prog->aux->func_cnt; i++) { 4983 len = prog->aux->func[i]->jited_len; 4984 len = min_t(u32, len, free); 4985 img = (u8 *) prog->aux->func[i]->bpf_func; 4986 if (copy_to_user(uinsns, img, len)) 4987 return -EFAULT; 4988 uinsns += len; 4989 free -= len; 4990 if (!free) 4991 break; 4992 } 4993 } else { 4994 if (copy_to_user(uinsns, prog->bpf_func, ulen)) 4995 return -EFAULT; 4996 } 4997 } else { 4998 info.jited_prog_insns = 0; 4999 } 5000 } 5001 5002 ulen = info.nr_jited_ksyms; 5003 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; 5004 if (ulen) { 5005 if (bpf_dump_raw_ok(file->f_cred)) { 5006 unsigned long ksym_addr; 5007 u64 __user *user_ksyms; 5008 u32 i; 5009 5010 /* copy the address of the kernel symbol 5011 * corresponding to each function 5012 */ 5013 ulen = min_t(u32, info.nr_jited_ksyms, ulen); 5014 user_ksyms = u64_to_user_ptr(info.jited_ksyms); 5015 if (prog->aux->func_cnt) { 5016 for (i = 0; i < ulen; i++) { 5017 ksym_addr = (unsigned long) 5018 prog->aux->func[i]->bpf_func; 5019 if (put_user((u64) ksym_addr, 5020 &user_ksyms[i])) 5021 return -EFAULT; 5022 } 5023 } else { 5024 ksym_addr = (unsigned long) prog->bpf_func; 5025 if (put_user((u64) ksym_addr, &user_ksyms[0])) 5026 return -EFAULT; 5027 } 5028 } else { 5029 info.jited_ksyms = 0; 5030 } 5031 } 5032 5033 ulen = info.nr_jited_func_lens; 5034 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; 5035 if (ulen) { 5036 if (bpf_dump_raw_ok(file->f_cred)) { 5037 u32 __user *user_lens; 5038 u32 func_len, i; 5039 5040 /* copy the JITed image lengths for each function */ 5041 ulen = min_t(u32, info.nr_jited_func_lens, ulen); 5042 user_lens = u64_to_user_ptr(info.jited_func_lens); 5043 if (prog->aux->func_cnt) { 5044 for (i = 0; i < ulen; i++) { 5045 func_len = 5046 prog->aux->func[i]->jited_len; 5047 if (put_user(func_len, &user_lens[i])) 5048 return -EFAULT; 5049 } 5050 } else { 5051 func_len = prog->jited_len; 5052 if (put_user(func_len, &user_lens[0])) 5053 return -EFAULT; 5054 } 5055 } else { 5056 info.jited_func_lens = 0; 5057 } 5058 } 5059 5060 info.attach_btf_id = prog->aux->attach_btf_id; 5061 if (attach_btf) 5062 info.attach_btf_obj_id = btf_obj_id(attach_btf); 5063 5064 ulen = info.nr_func_info; 5065 info.nr_func_info = prog->aux->func_info_cnt; 5066 if (info.nr_func_info && ulen) { 5067 char __user *user_finfo; 5068 5069 user_finfo = u64_to_user_ptr(info.func_info); 5070 ulen = min_t(u32, info.nr_func_info, ulen); 5071 if (copy_to_user(user_finfo, prog->aux->func_info, 5072 info.func_info_rec_size * ulen)) 5073 return -EFAULT; 5074 } 5075 5076 ulen = info.nr_line_info; 5077 info.nr_line_info = prog->aux->nr_linfo; 5078 if (info.nr_line_info && ulen) { 5079 __u8 __user *user_linfo; 5080 5081 user_linfo = u64_to_user_ptr(info.line_info); 5082 ulen = min_t(u32, info.nr_line_info, ulen); 5083 if (copy_to_user(user_linfo, prog->aux->linfo, 5084 info.line_info_rec_size * ulen)) 5085 return -EFAULT; 5086 } 5087 5088 ulen = info.nr_jited_line_info; 5089 if (prog->aux->jited_linfo) 5090 info.nr_jited_line_info = prog->aux->nr_linfo; 5091 else 5092 info.nr_jited_line_info = 0; 5093 if (info.nr_jited_line_info && ulen) { 5094 if (bpf_dump_raw_ok(file->f_cred)) { 5095 unsigned long line_addr; 5096 __u64 __user *user_linfo; 5097 u32 i; 5098 5099 user_linfo = u64_to_user_ptr(info.jited_line_info); 5100 ulen = min_t(u32, info.nr_jited_line_info, ulen); 5101 for (i = 0; i < ulen; i++) { 5102 line_addr = (unsigned long)prog->aux->jited_linfo[i]; 5103 if (put_user((__u64)line_addr, &user_linfo[i])) 5104 return -EFAULT; 5105 } 5106 } else { 5107 info.jited_line_info = 0; 5108 } 5109 } 5110 5111 ulen = info.nr_prog_tags; 5112 info.nr_prog_tags = prog->aux->func_cnt ? : 1; 5113 if (ulen) { 5114 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; 5115 u32 i; 5116 5117 user_prog_tags = u64_to_user_ptr(info.prog_tags); 5118 ulen = min_t(u32, info.nr_prog_tags, ulen); 5119 if (prog->aux->func_cnt) { 5120 for (i = 0; i < ulen; i++) { 5121 if (copy_to_user(user_prog_tags[i], 5122 prog->aux->func[i]->tag, 5123 BPF_TAG_SIZE)) 5124 return -EFAULT; 5125 } 5126 } else { 5127 if (copy_to_user(user_prog_tags[0], 5128 prog->tag, BPF_TAG_SIZE)) 5129 return -EFAULT; 5130 } 5131 } 5132 5133 done: 5134 if (copy_to_user(uinfo, &info, info_len) || 5135 put_user(info_len, &uattr->info.info_len)) 5136 return -EFAULT; 5137 5138 return 0; 5139 } 5140 5141 static int bpf_map_get_info_by_fd(struct file *file, 5142 struct bpf_map *map, 5143 const union bpf_attr *attr, 5144 union bpf_attr __user *uattr) 5145 { 5146 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5147 struct bpf_map_info info; 5148 u32 info_len = attr->info.info_len; 5149 int err; 5150 5151 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5152 if (err) 5153 return err; 5154 info_len = min_t(u32, sizeof(info), info_len); 5155 5156 memset(&info, 0, sizeof(info)); 5157 info.type = map->map_type; 5158 info.id = map->id; 5159 info.key_size = map->key_size; 5160 info.value_size = map->value_size; 5161 info.max_entries = map->max_entries; 5162 info.map_flags = map->map_flags; 5163 info.map_extra = map->map_extra; 5164 memcpy(info.name, map->name, sizeof(map->name)); 5165 5166 if (map->btf) { 5167 info.btf_id = btf_obj_id(map->btf); 5168 info.btf_key_type_id = map->btf_key_type_id; 5169 info.btf_value_type_id = map->btf_value_type_id; 5170 } 5171 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; 5172 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) 5173 bpf_map_struct_ops_info_fill(&info, map); 5174 5175 if (bpf_map_is_offloaded(map)) { 5176 err = bpf_map_offload_info_fill(&info, map); 5177 if (err) 5178 return err; 5179 } 5180 5181 if (copy_to_user(uinfo, &info, info_len) || 5182 put_user(info_len, &uattr->info.info_len)) 5183 return -EFAULT; 5184 5185 return 0; 5186 } 5187 5188 static int bpf_btf_get_info_by_fd(struct file *file, 5189 struct btf *btf, 5190 const union bpf_attr *attr, 5191 union bpf_attr __user *uattr) 5192 { 5193 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5194 u32 info_len = attr->info.info_len; 5195 int err; 5196 5197 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5198 if (err) 5199 return err; 5200 5201 return btf_get_info_by_fd(btf, attr, uattr); 5202 } 5203 5204 static int bpf_link_get_info_by_fd(struct file *file, 5205 struct bpf_link *link, 5206 const union bpf_attr *attr, 5207 union bpf_attr __user *uattr) 5208 { 5209 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5210 struct bpf_link_info info; 5211 u32 info_len = attr->info.info_len; 5212 int err; 5213 5214 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); 5215 if (err) 5216 return err; 5217 info_len = min_t(u32, sizeof(info), info_len); 5218 5219 memset(&info, 0, sizeof(info)); 5220 if (copy_from_user(&info, uinfo, info_len)) 5221 return -EFAULT; 5222 5223 info.type = link->type; 5224 info.id = link->id; 5225 if (link->prog) 5226 info.prog_id = link->prog->aux->id; 5227 5228 if (link->ops->fill_link_info) { 5229 err = link->ops->fill_link_info(link, &info); 5230 if (err) 5231 return err; 5232 } 5233 5234 if (copy_to_user(uinfo, &info, info_len) || 5235 put_user(info_len, &uattr->info.info_len)) 5236 return -EFAULT; 5237 5238 return 0; 5239 } 5240 5241 5242 static int token_get_info_by_fd(struct file *file, 5243 struct bpf_token *token, 5244 const union bpf_attr *attr, 5245 union bpf_attr __user *uattr) 5246 { 5247 struct bpf_token_info __user *uinfo = u64_to_user_ptr(attr->info.info); 5248 u32 info_len = attr->info.info_len; 5249 int err; 5250 5251 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); 5252 if (err) 5253 return err; 5254 return bpf_token_get_info_by_fd(token, attr, uattr); 5255 } 5256 5257 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info 5258 5259 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, 5260 union bpf_attr __user *uattr) 5261 { 5262 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) 5263 return -EINVAL; 5264 5265 CLASS(fd, f)(attr->info.bpf_fd); 5266 if (fd_empty(f)) 5267 return -EBADFD; 5268 5269 if (fd_file(f)->f_op == &bpf_prog_fops) 5270 return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5271 uattr); 5272 else if (fd_file(f)->f_op == &bpf_map_fops) 5273 return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, 5274 uattr); 5275 else if (fd_file(f)->f_op == &btf_fops) 5276 return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr); 5277 else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll) 5278 return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5279 attr, uattr); 5280 else if (fd_file(f)->f_op == &bpf_token_fops) 5281 return token_get_info_by_fd(fd_file(f), fd_file(f)->private_data, 5282 attr, uattr); 5283 return -EINVAL; 5284 } 5285 5286 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd 5287 5288 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) 5289 { 5290 struct bpf_token *token = NULL; 5291 5292 if (CHECK_ATTR(BPF_BTF_LOAD)) 5293 return -EINVAL; 5294 5295 if (attr->btf_flags & ~BPF_F_TOKEN_FD) 5296 return -EINVAL; 5297 5298 if (attr->btf_flags & BPF_F_TOKEN_FD) { 5299 token = bpf_token_get_from_fd(attr->btf_token_fd); 5300 if (IS_ERR(token)) 5301 return PTR_ERR(token); 5302 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { 5303 bpf_token_put(token); 5304 token = NULL; 5305 } 5306 } 5307 5308 if (!bpf_token_capable(token, CAP_BPF)) { 5309 bpf_token_put(token); 5310 return -EPERM; 5311 } 5312 5313 bpf_token_put(token); 5314 5315 return btf_new_fd(attr, uattr, uattr_size); 5316 } 5317 5318 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD fd_by_id_token_fd 5319 5320 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) 5321 { 5322 struct bpf_token *token = NULL; 5323 5324 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) 5325 return -EINVAL; 5326 5327 if (attr->open_flags & ~BPF_F_TOKEN_FD) 5328 return -EINVAL; 5329 5330 if (attr->open_flags & BPF_F_TOKEN_FD) { 5331 token = bpf_token_get_from_fd(attr->fd_by_id_token_fd); 5332 if (IS_ERR(token)) 5333 return PTR_ERR(token); 5334 if (!bpf_token_allow_cmd(token, BPF_BTF_GET_FD_BY_ID)) { 5335 bpf_token_put(token); 5336 token = NULL; 5337 } 5338 } 5339 5340 if (!bpf_token_capable(token, CAP_SYS_ADMIN)) { 5341 bpf_token_put(token); 5342 return -EPERM; 5343 } 5344 5345 bpf_token_put(token); 5346 5347 return btf_get_fd_by_id(attr->btf_id); 5348 } 5349 5350 static int bpf_task_fd_query_copy(const union bpf_attr *attr, 5351 union bpf_attr __user *uattr, 5352 u32 prog_id, u32 fd_type, 5353 const char *buf, u64 probe_offset, 5354 u64 probe_addr) 5355 { 5356 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); 5357 u32 len = buf ? strlen(buf) : 0, input_len; 5358 int err = 0; 5359 5360 if (put_user(len, &uattr->task_fd_query.buf_len)) 5361 return -EFAULT; 5362 input_len = attr->task_fd_query.buf_len; 5363 if (input_len && ubuf) { 5364 if (!len) { 5365 /* nothing to copy, just make ubuf NULL terminated */ 5366 char zero = '\0'; 5367 5368 if (put_user(zero, ubuf)) 5369 return -EFAULT; 5370 } else { 5371 err = bpf_copy_to_user(ubuf, buf, input_len, len); 5372 if (err == -EFAULT) 5373 return err; 5374 } 5375 } 5376 5377 if (put_user(prog_id, &uattr->task_fd_query.prog_id) || 5378 put_user(fd_type, &uattr->task_fd_query.fd_type) || 5379 put_user(probe_offset, &uattr->task_fd_query.probe_offset) || 5380 put_user(probe_addr, &uattr->task_fd_query.probe_addr)) 5381 return -EFAULT; 5382 5383 return err; 5384 } 5385 5386 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr 5387 5388 static int bpf_task_fd_query(const union bpf_attr *attr, 5389 union bpf_attr __user *uattr) 5390 { 5391 pid_t pid = attr->task_fd_query.pid; 5392 u32 fd = attr->task_fd_query.fd; 5393 const struct perf_event *event; 5394 struct task_struct *task; 5395 struct file *file; 5396 int err; 5397 5398 if (CHECK_ATTR(BPF_TASK_FD_QUERY)) 5399 return -EINVAL; 5400 5401 if (!capable(CAP_SYS_ADMIN)) 5402 return -EPERM; 5403 5404 if (attr->task_fd_query.flags != 0) 5405 return -EINVAL; 5406 5407 rcu_read_lock(); 5408 task = get_pid_task(find_vpid(pid), PIDTYPE_PID); 5409 rcu_read_unlock(); 5410 if (!task) 5411 return -ENOENT; 5412 5413 err = 0; 5414 file = fget_task(task, fd); 5415 put_task_struct(task); 5416 if (!file) 5417 return -EBADF; 5418 5419 if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) { 5420 struct bpf_link *link = file->private_data; 5421 5422 if (link->ops == &bpf_raw_tp_link_lops) { 5423 struct bpf_raw_tp_link *raw_tp = 5424 container_of(link, struct bpf_raw_tp_link, link); 5425 struct bpf_raw_event_map *btp = raw_tp->btp; 5426 5427 err = bpf_task_fd_query_copy(attr, uattr, 5428 raw_tp->link.prog->aux->id, 5429 BPF_FD_TYPE_RAW_TRACEPOINT, 5430 btp->tp->name, 0, 0); 5431 goto put_file; 5432 } 5433 goto out_not_supp; 5434 } 5435 5436 event = perf_get_event(file); 5437 if (!IS_ERR(event)) { 5438 u64 probe_offset, probe_addr; 5439 u32 prog_id, fd_type; 5440 const char *buf; 5441 5442 err = bpf_get_perf_event_info(event, &prog_id, &fd_type, 5443 &buf, &probe_offset, 5444 &probe_addr, NULL); 5445 if (!err) 5446 err = bpf_task_fd_query_copy(attr, uattr, prog_id, 5447 fd_type, buf, 5448 probe_offset, 5449 probe_addr); 5450 goto put_file; 5451 } 5452 5453 out_not_supp: 5454 err = -ENOTSUPP; 5455 put_file: 5456 fput(file); 5457 return err; 5458 } 5459 5460 #define BPF_MAP_BATCH_LAST_FIELD batch.flags 5461 5462 #define BPF_DO_BATCH(fn, ...) \ 5463 do { \ 5464 if (!fn) { \ 5465 err = -ENOTSUPP; \ 5466 goto err_put; \ 5467 } \ 5468 err = fn(__VA_ARGS__); \ 5469 } while (0) 5470 5471 static int bpf_map_do_batch(const union bpf_attr *attr, 5472 union bpf_attr __user *uattr, 5473 int cmd) 5474 { 5475 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || 5476 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; 5477 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; 5478 struct bpf_map *map; 5479 int err; 5480 5481 if (CHECK_ATTR(BPF_MAP_BATCH)) 5482 return -EINVAL; 5483 5484 CLASS(fd, f)(attr->batch.map_fd); 5485 5486 map = __bpf_map_get(f); 5487 if (IS_ERR(map)) 5488 return PTR_ERR(map); 5489 if (has_write) 5490 bpf_map_write_active_inc(map); 5491 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { 5492 err = -EPERM; 5493 goto err_put; 5494 } 5495 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { 5496 err = -EPERM; 5497 goto err_put; 5498 } 5499 5500 if (cmd == BPF_MAP_LOOKUP_BATCH) 5501 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); 5502 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) 5503 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); 5504 else if (cmd == BPF_MAP_UPDATE_BATCH) 5505 BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr); 5506 else 5507 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); 5508 err_put: 5509 if (has_write) { 5510 maybe_wait_bpf_programs(map); 5511 bpf_map_write_active_dec(map); 5512 } 5513 return err; 5514 } 5515 5516 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid 5517 static int link_create(union bpf_attr *attr, bpfptr_t uattr) 5518 { 5519 struct bpf_prog *prog; 5520 int ret; 5521 5522 if (CHECK_ATTR(BPF_LINK_CREATE)) 5523 return -EINVAL; 5524 5525 if (attr->link_create.attach_type == BPF_STRUCT_OPS) 5526 return bpf_struct_ops_link_create(attr); 5527 5528 prog = bpf_prog_get(attr->link_create.prog_fd); 5529 if (IS_ERR(prog)) 5530 return PTR_ERR(prog); 5531 5532 ret = bpf_prog_attach_check_attach_type(prog, 5533 attr->link_create.attach_type); 5534 if (ret) 5535 goto out; 5536 5537 switch (prog->type) { 5538 case BPF_PROG_TYPE_CGROUP_SKB: 5539 case BPF_PROG_TYPE_CGROUP_SOCK: 5540 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: 5541 case BPF_PROG_TYPE_SOCK_OPS: 5542 case BPF_PROG_TYPE_CGROUP_DEVICE: 5543 case BPF_PROG_TYPE_CGROUP_SYSCTL: 5544 case BPF_PROG_TYPE_CGROUP_SOCKOPT: 5545 ret = cgroup_bpf_link_attach(attr, prog); 5546 break; 5547 case BPF_PROG_TYPE_EXT: 5548 ret = bpf_tracing_prog_attach(prog, 5549 attr->link_create.target_fd, 5550 attr->link_create.target_btf_id, 5551 attr->link_create.tracing.cookie, 5552 attr->link_create.attach_type); 5553 break; 5554 case BPF_PROG_TYPE_LSM: 5555 case BPF_PROG_TYPE_TRACING: 5556 if (attr->link_create.attach_type != prog->expected_attach_type) { 5557 ret = -EINVAL; 5558 goto out; 5559 } 5560 if (prog->expected_attach_type == BPF_TRACE_RAW_TP) 5561 ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie, 5562 attr->link_create.attach_type); 5563 else if (prog->expected_attach_type == BPF_TRACE_ITER) 5564 ret = bpf_iter_link_attach(attr, uattr, prog); 5565 else if (prog->expected_attach_type == BPF_LSM_CGROUP) 5566 ret = cgroup_bpf_link_attach(attr, prog); 5567 else 5568 ret = bpf_tracing_prog_attach(prog, 5569 attr->link_create.target_fd, 5570 attr->link_create.target_btf_id, 5571 attr->link_create.tracing.cookie, 5572 attr->link_create.attach_type); 5573 break; 5574 case BPF_PROG_TYPE_FLOW_DISSECTOR: 5575 case BPF_PROG_TYPE_SK_LOOKUP: 5576 ret = netns_bpf_link_create(attr, prog); 5577 break; 5578 case BPF_PROG_TYPE_SK_MSG: 5579 case BPF_PROG_TYPE_SK_SKB: 5580 ret = sock_map_link_create(attr, prog); 5581 break; 5582 #ifdef CONFIG_NET 5583 case BPF_PROG_TYPE_XDP: 5584 ret = bpf_xdp_link_attach(attr, prog); 5585 break; 5586 case BPF_PROG_TYPE_SCHED_CLS: 5587 if (attr->link_create.attach_type == BPF_TCX_INGRESS || 5588 attr->link_create.attach_type == BPF_TCX_EGRESS) 5589 ret = tcx_link_attach(attr, prog); 5590 else 5591 ret = netkit_link_attach(attr, prog); 5592 break; 5593 case BPF_PROG_TYPE_NETFILTER: 5594 ret = bpf_nf_link_attach(attr, prog); 5595 break; 5596 #endif 5597 case BPF_PROG_TYPE_PERF_EVENT: 5598 case BPF_PROG_TYPE_TRACEPOINT: 5599 ret = bpf_perf_link_attach(attr, prog); 5600 break; 5601 case BPF_PROG_TYPE_KPROBE: 5602 if (attr->link_create.attach_type == BPF_PERF_EVENT) 5603 ret = bpf_perf_link_attach(attr, prog); 5604 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI || 5605 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION) 5606 ret = bpf_kprobe_multi_link_attach(attr, prog); 5607 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI || 5608 attr->link_create.attach_type == BPF_TRACE_UPROBE_SESSION) 5609 ret = bpf_uprobe_multi_link_attach(attr, prog); 5610 break; 5611 default: 5612 ret = -EINVAL; 5613 } 5614 5615 out: 5616 if (ret < 0) 5617 bpf_prog_put(prog); 5618 return ret; 5619 } 5620 5621 static int link_update_map(struct bpf_link *link, union bpf_attr *attr) 5622 { 5623 struct bpf_map *new_map, *old_map = NULL; 5624 int ret; 5625 5626 new_map = bpf_map_get(attr->link_update.new_map_fd); 5627 if (IS_ERR(new_map)) 5628 return PTR_ERR(new_map); 5629 5630 if (attr->link_update.flags & BPF_F_REPLACE) { 5631 old_map = bpf_map_get(attr->link_update.old_map_fd); 5632 if (IS_ERR(old_map)) { 5633 ret = PTR_ERR(old_map); 5634 goto out_put; 5635 } 5636 } else if (attr->link_update.old_map_fd) { 5637 ret = -EINVAL; 5638 goto out_put; 5639 } 5640 5641 ret = link->ops->update_map(link, new_map, old_map); 5642 5643 if (old_map) 5644 bpf_map_put(old_map); 5645 out_put: 5646 bpf_map_put(new_map); 5647 return ret; 5648 } 5649 5650 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd 5651 5652 static int link_update(union bpf_attr *attr) 5653 { 5654 struct bpf_prog *old_prog = NULL, *new_prog; 5655 struct bpf_link *link; 5656 u32 flags; 5657 int ret; 5658 5659 if (CHECK_ATTR(BPF_LINK_UPDATE)) 5660 return -EINVAL; 5661 5662 flags = attr->link_update.flags; 5663 if (flags & ~BPF_F_REPLACE) 5664 return -EINVAL; 5665 5666 link = bpf_link_get_from_fd(attr->link_update.link_fd); 5667 if (IS_ERR(link)) 5668 return PTR_ERR(link); 5669 5670 if (link->ops->update_map) { 5671 ret = link_update_map(link, attr); 5672 goto out_put_link; 5673 } 5674 5675 new_prog = bpf_prog_get(attr->link_update.new_prog_fd); 5676 if (IS_ERR(new_prog)) { 5677 ret = PTR_ERR(new_prog); 5678 goto out_put_link; 5679 } 5680 5681 if (flags & BPF_F_REPLACE) { 5682 old_prog = bpf_prog_get(attr->link_update.old_prog_fd); 5683 if (IS_ERR(old_prog)) { 5684 ret = PTR_ERR(old_prog); 5685 old_prog = NULL; 5686 goto out_put_progs; 5687 } 5688 } else if (attr->link_update.old_prog_fd) { 5689 ret = -EINVAL; 5690 goto out_put_progs; 5691 } 5692 5693 if (link->ops->update_prog) 5694 ret = link->ops->update_prog(link, new_prog, old_prog); 5695 else 5696 ret = -EINVAL; 5697 5698 out_put_progs: 5699 if (old_prog) 5700 bpf_prog_put(old_prog); 5701 if (ret) 5702 bpf_prog_put(new_prog); 5703 out_put_link: 5704 bpf_link_put_direct(link); 5705 return ret; 5706 } 5707 5708 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd 5709 5710 static int link_detach(union bpf_attr *attr) 5711 { 5712 struct bpf_link *link; 5713 int ret; 5714 5715 if (CHECK_ATTR(BPF_LINK_DETACH)) 5716 return -EINVAL; 5717 5718 link = bpf_link_get_from_fd(attr->link_detach.link_fd); 5719 if (IS_ERR(link)) 5720 return PTR_ERR(link); 5721 5722 if (link->ops->detach) 5723 ret = link->ops->detach(link); 5724 else 5725 ret = -EOPNOTSUPP; 5726 5727 bpf_link_put_direct(link); 5728 return ret; 5729 } 5730 5731 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) 5732 { 5733 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); 5734 } 5735 EXPORT_SYMBOL(bpf_link_inc_not_zero); 5736 5737 struct bpf_link *bpf_link_by_id(u32 id) 5738 { 5739 struct bpf_link *link; 5740 5741 if (!id) 5742 return ERR_PTR(-ENOENT); 5743 5744 spin_lock_bh(&link_idr_lock); 5745 /* before link is "settled", ID is 0, pretend it doesn't exist yet */ 5746 link = idr_find(&link_idr, id); 5747 if (link) { 5748 if (link->id) 5749 link = bpf_link_inc_not_zero(link); 5750 else 5751 link = ERR_PTR(-EAGAIN); 5752 } else { 5753 link = ERR_PTR(-ENOENT); 5754 } 5755 spin_unlock_bh(&link_idr_lock); 5756 return link; 5757 } 5758 5759 struct bpf_link *bpf_link_get_curr_or_next(u32 *id) 5760 { 5761 struct bpf_link *link; 5762 5763 spin_lock_bh(&link_idr_lock); 5764 again: 5765 link = idr_get_next(&link_idr, id); 5766 if (link) { 5767 link = bpf_link_inc_not_zero(link); 5768 if (IS_ERR(link)) { 5769 (*id)++; 5770 goto again; 5771 } 5772 } 5773 spin_unlock_bh(&link_idr_lock); 5774 5775 return link; 5776 } 5777 5778 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id 5779 5780 static int bpf_link_get_fd_by_id(const union bpf_attr *attr) 5781 { 5782 struct bpf_link *link; 5783 u32 id = attr->link_id; 5784 int fd; 5785 5786 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) 5787 return -EINVAL; 5788 5789 if (!capable(CAP_SYS_ADMIN)) 5790 return -EPERM; 5791 5792 link = bpf_link_by_id(id); 5793 if (IS_ERR(link)) 5794 return PTR_ERR(link); 5795 5796 fd = bpf_link_new_fd(link); 5797 if (fd < 0) 5798 bpf_link_put_direct(link); 5799 5800 return fd; 5801 } 5802 5803 DEFINE_MUTEX(bpf_stats_enabled_mutex); 5804 5805 static int bpf_stats_release(struct inode *inode, struct file *file) 5806 { 5807 mutex_lock(&bpf_stats_enabled_mutex); 5808 static_key_slow_dec(&bpf_stats_enabled_key.key); 5809 mutex_unlock(&bpf_stats_enabled_mutex); 5810 return 0; 5811 } 5812 5813 static const struct file_operations bpf_stats_fops = { 5814 .release = bpf_stats_release, 5815 }; 5816 5817 static int bpf_enable_runtime_stats(void) 5818 { 5819 int fd; 5820 5821 mutex_lock(&bpf_stats_enabled_mutex); 5822 5823 /* Set a very high limit to avoid overflow */ 5824 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { 5825 mutex_unlock(&bpf_stats_enabled_mutex); 5826 return -EBUSY; 5827 } 5828 5829 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); 5830 if (fd >= 0) 5831 static_key_slow_inc(&bpf_stats_enabled_key.key); 5832 5833 mutex_unlock(&bpf_stats_enabled_mutex); 5834 return fd; 5835 } 5836 5837 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type 5838 5839 static int bpf_enable_stats(union bpf_attr *attr) 5840 { 5841 5842 if (CHECK_ATTR(BPF_ENABLE_STATS)) 5843 return -EINVAL; 5844 5845 if (!capable(CAP_SYS_ADMIN)) 5846 return -EPERM; 5847 5848 switch (attr->enable_stats.type) { 5849 case BPF_STATS_RUN_TIME: 5850 return bpf_enable_runtime_stats(); 5851 default: 5852 break; 5853 } 5854 return -EINVAL; 5855 } 5856 5857 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags 5858 5859 static int bpf_iter_create(union bpf_attr *attr) 5860 { 5861 struct bpf_link *link; 5862 int err; 5863 5864 if (CHECK_ATTR(BPF_ITER_CREATE)) 5865 return -EINVAL; 5866 5867 if (attr->iter_create.flags) 5868 return -EINVAL; 5869 5870 link = bpf_link_get_from_fd(attr->iter_create.link_fd); 5871 if (IS_ERR(link)) 5872 return PTR_ERR(link); 5873 5874 err = bpf_iter_new_fd(link); 5875 bpf_link_put_direct(link); 5876 5877 return err; 5878 } 5879 5880 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags 5881 5882 static int bpf_prog_bind_map(union bpf_attr *attr) 5883 { 5884 struct bpf_prog *prog; 5885 struct bpf_map *map; 5886 struct bpf_map **used_maps_old, **used_maps_new; 5887 int i, ret = 0; 5888 5889 if (CHECK_ATTR(BPF_PROG_BIND_MAP)) 5890 return -EINVAL; 5891 5892 if (attr->prog_bind_map.flags) 5893 return -EINVAL; 5894 5895 prog = bpf_prog_get(attr->prog_bind_map.prog_fd); 5896 if (IS_ERR(prog)) 5897 return PTR_ERR(prog); 5898 5899 map = bpf_map_get(attr->prog_bind_map.map_fd); 5900 if (IS_ERR(map)) { 5901 ret = PTR_ERR(map); 5902 goto out_prog_put; 5903 } 5904 5905 mutex_lock(&prog->aux->used_maps_mutex); 5906 5907 used_maps_old = prog->aux->used_maps; 5908 5909 for (i = 0; i < prog->aux->used_map_cnt; i++) 5910 if (used_maps_old[i] == map) { 5911 bpf_map_put(map); 5912 goto out_unlock; 5913 } 5914 5915 used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, 5916 sizeof(used_maps_new[0]), 5917 GFP_KERNEL); 5918 if (!used_maps_new) { 5919 ret = -ENOMEM; 5920 goto out_unlock; 5921 } 5922 5923 /* The bpf program will not access the bpf map, but for the sake of 5924 * simplicity, increase sleepable_refcnt for sleepable program as well. 5925 */ 5926 if (prog->sleepable) 5927 atomic64_inc(&map->sleepable_refcnt); 5928 memcpy(used_maps_new, used_maps_old, 5929 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); 5930 used_maps_new[prog->aux->used_map_cnt] = map; 5931 5932 prog->aux->used_map_cnt++; 5933 prog->aux->used_maps = used_maps_new; 5934 5935 kfree(used_maps_old); 5936 5937 out_unlock: 5938 mutex_unlock(&prog->aux->used_maps_mutex); 5939 5940 if (ret) 5941 bpf_map_put(map); 5942 out_prog_put: 5943 bpf_prog_put(prog); 5944 return ret; 5945 } 5946 5947 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd 5948 5949 static int token_create(union bpf_attr *attr) 5950 { 5951 if (CHECK_ATTR(BPF_TOKEN_CREATE)) 5952 return -EINVAL; 5953 5954 /* no flags are supported yet */ 5955 if (attr->token_create.flags) 5956 return -EINVAL; 5957 5958 return bpf_token_create(attr); 5959 } 5960 5961 #define BPF_PROG_STREAM_READ_BY_FD_LAST_FIELD prog_stream_read.prog_fd 5962 5963 static int prog_stream_read(union bpf_attr *attr) 5964 { 5965 char __user *buf = u64_to_user_ptr(attr->prog_stream_read.stream_buf); 5966 u32 len = attr->prog_stream_read.stream_buf_len; 5967 struct bpf_prog *prog; 5968 int ret; 5969 5970 if (CHECK_ATTR(BPF_PROG_STREAM_READ_BY_FD)) 5971 return -EINVAL; 5972 5973 prog = bpf_prog_get(attr->prog_stream_read.prog_fd); 5974 if (IS_ERR(prog)) 5975 return PTR_ERR(prog); 5976 5977 ret = bpf_prog_stream_read(prog, attr->prog_stream_read.stream_id, buf, len); 5978 bpf_prog_put(prog); 5979 5980 return ret; 5981 } 5982 5983 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size) 5984 { 5985 union bpf_attr attr; 5986 int err; 5987 5988 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); 5989 if (err) 5990 return err; 5991 size = min_t(u32, size, sizeof(attr)); 5992 5993 /* copy attributes from user space, may be less than sizeof(bpf_attr) */ 5994 memset(&attr, 0, sizeof(attr)); 5995 if (copy_from_bpfptr(&attr, uattr, size) != 0) 5996 return -EFAULT; 5997 5998 err = security_bpf(cmd, &attr, size, uattr.is_kernel); 5999 if (err < 0) 6000 return err; 6001 6002 switch (cmd) { 6003 case BPF_MAP_CREATE: 6004 err = map_create(&attr, uattr.is_kernel); 6005 break; 6006 case BPF_MAP_LOOKUP_ELEM: 6007 err = map_lookup_elem(&attr); 6008 break; 6009 case BPF_MAP_UPDATE_ELEM: 6010 err = map_update_elem(&attr, uattr); 6011 break; 6012 case BPF_MAP_DELETE_ELEM: 6013 err = map_delete_elem(&attr, uattr); 6014 break; 6015 case BPF_MAP_GET_NEXT_KEY: 6016 err = map_get_next_key(&attr); 6017 break; 6018 case BPF_MAP_FREEZE: 6019 err = map_freeze(&attr); 6020 break; 6021 case BPF_PROG_LOAD: 6022 err = bpf_prog_load(&attr, uattr, size); 6023 break; 6024 case BPF_OBJ_PIN: 6025 err = bpf_obj_pin(&attr); 6026 break; 6027 case BPF_OBJ_GET: 6028 err = bpf_obj_get(&attr); 6029 break; 6030 case BPF_PROG_ATTACH: 6031 err = bpf_prog_attach(&attr); 6032 break; 6033 case BPF_PROG_DETACH: 6034 err = bpf_prog_detach(&attr); 6035 break; 6036 case BPF_PROG_QUERY: 6037 err = bpf_prog_query(&attr, uattr.user); 6038 break; 6039 case BPF_PROG_TEST_RUN: 6040 err = bpf_prog_test_run(&attr, uattr.user); 6041 break; 6042 case BPF_PROG_GET_NEXT_ID: 6043 err = bpf_obj_get_next_id(&attr, uattr.user, 6044 &prog_idr, &prog_idr_lock); 6045 break; 6046 case BPF_MAP_GET_NEXT_ID: 6047 err = bpf_obj_get_next_id(&attr, uattr.user, 6048 &map_idr, &map_idr_lock); 6049 break; 6050 case BPF_BTF_GET_NEXT_ID: 6051 err = bpf_obj_get_next_id(&attr, uattr.user, 6052 &btf_idr, &btf_idr_lock); 6053 break; 6054 case BPF_PROG_GET_FD_BY_ID: 6055 err = bpf_prog_get_fd_by_id(&attr); 6056 break; 6057 case BPF_MAP_GET_FD_BY_ID: 6058 err = bpf_map_get_fd_by_id(&attr); 6059 break; 6060 case BPF_OBJ_GET_INFO_BY_FD: 6061 err = bpf_obj_get_info_by_fd(&attr, uattr.user); 6062 break; 6063 case BPF_RAW_TRACEPOINT_OPEN: 6064 err = bpf_raw_tracepoint_open(&attr); 6065 break; 6066 case BPF_BTF_LOAD: 6067 err = bpf_btf_load(&attr, uattr, size); 6068 break; 6069 case BPF_BTF_GET_FD_BY_ID: 6070 err = bpf_btf_get_fd_by_id(&attr); 6071 break; 6072 case BPF_TASK_FD_QUERY: 6073 err = bpf_task_fd_query(&attr, uattr.user); 6074 break; 6075 case BPF_MAP_LOOKUP_AND_DELETE_ELEM: 6076 err = map_lookup_and_delete_elem(&attr); 6077 break; 6078 case BPF_MAP_LOOKUP_BATCH: 6079 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); 6080 break; 6081 case BPF_MAP_LOOKUP_AND_DELETE_BATCH: 6082 err = bpf_map_do_batch(&attr, uattr.user, 6083 BPF_MAP_LOOKUP_AND_DELETE_BATCH); 6084 break; 6085 case BPF_MAP_UPDATE_BATCH: 6086 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); 6087 break; 6088 case BPF_MAP_DELETE_BATCH: 6089 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); 6090 break; 6091 case BPF_LINK_CREATE: 6092 err = link_create(&attr, uattr); 6093 break; 6094 case BPF_LINK_UPDATE: 6095 err = link_update(&attr); 6096 break; 6097 case BPF_LINK_GET_FD_BY_ID: 6098 err = bpf_link_get_fd_by_id(&attr); 6099 break; 6100 case BPF_LINK_GET_NEXT_ID: 6101 err = bpf_obj_get_next_id(&attr, uattr.user, 6102 &link_idr, &link_idr_lock); 6103 break; 6104 case BPF_ENABLE_STATS: 6105 err = bpf_enable_stats(&attr); 6106 break; 6107 case BPF_ITER_CREATE: 6108 err = bpf_iter_create(&attr); 6109 break; 6110 case BPF_LINK_DETACH: 6111 err = link_detach(&attr); 6112 break; 6113 case BPF_PROG_BIND_MAP: 6114 err = bpf_prog_bind_map(&attr); 6115 break; 6116 case BPF_TOKEN_CREATE: 6117 err = token_create(&attr); 6118 break; 6119 case BPF_PROG_STREAM_READ_BY_FD: 6120 err = prog_stream_read(&attr); 6121 break; 6122 default: 6123 err = -EINVAL; 6124 break; 6125 } 6126 6127 return err; 6128 } 6129 6130 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) 6131 { 6132 return __sys_bpf(cmd, USER_BPFPTR(uattr), size); 6133 } 6134 6135 static bool syscall_prog_is_valid_access(int off, int size, 6136 enum bpf_access_type type, 6137 const struct bpf_prog *prog, 6138 struct bpf_insn_access_aux *info) 6139 { 6140 if (off < 0 || off >= U16_MAX) 6141 return false; 6142 if (off % size != 0) 6143 return false; 6144 return true; 6145 } 6146 6147 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) 6148 { 6149 switch (cmd) { 6150 case BPF_MAP_CREATE: 6151 case BPF_MAP_DELETE_ELEM: 6152 case BPF_MAP_UPDATE_ELEM: 6153 case BPF_MAP_FREEZE: 6154 case BPF_MAP_GET_FD_BY_ID: 6155 case BPF_PROG_LOAD: 6156 case BPF_BTF_LOAD: 6157 case BPF_LINK_CREATE: 6158 case BPF_RAW_TRACEPOINT_OPEN: 6159 break; 6160 default: 6161 return -EINVAL; 6162 } 6163 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); 6164 } 6165 6166 6167 /* To shut up -Wmissing-prototypes. 6168 * This function is used by the kernel light skeleton 6169 * to load bpf programs when modules are loaded or during kernel boot. 6170 * See tools/lib/bpf/skel_internal.h 6171 */ 6172 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); 6173 6174 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) 6175 { 6176 struct bpf_prog * __maybe_unused prog; 6177 struct bpf_tramp_run_ctx __maybe_unused run_ctx; 6178 6179 switch (cmd) { 6180 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ 6181 case BPF_PROG_TEST_RUN: 6182 if (attr->test.data_in || attr->test.data_out || 6183 attr->test.ctx_out || attr->test.duration || 6184 attr->test.repeat || attr->test.flags) 6185 return -EINVAL; 6186 6187 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); 6188 if (IS_ERR(prog)) 6189 return PTR_ERR(prog); 6190 6191 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || 6192 attr->test.ctx_size_in > U16_MAX) { 6193 bpf_prog_put(prog); 6194 return -EINVAL; 6195 } 6196 6197 run_ctx.bpf_cookie = 0; 6198 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { 6199 /* recursion detected */ 6200 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); 6201 bpf_prog_put(prog); 6202 return -EBUSY; 6203 } 6204 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); 6205 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, 6206 &run_ctx); 6207 bpf_prog_put(prog); 6208 return 0; 6209 #endif 6210 default: 6211 return ____bpf_sys_bpf(cmd, attr, size); 6212 } 6213 } 6214 EXPORT_SYMBOL_NS(kern_sys_bpf, "BPF_INTERNAL"); 6215 6216 static const struct bpf_func_proto bpf_sys_bpf_proto = { 6217 .func = bpf_sys_bpf, 6218 .gpl_only = false, 6219 .ret_type = RET_INTEGER, 6220 .arg1_type = ARG_ANYTHING, 6221 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, 6222 .arg3_type = ARG_CONST_SIZE, 6223 }; 6224 6225 const struct bpf_func_proto * __weak 6226 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6227 { 6228 return bpf_base_func_proto(func_id, prog); 6229 } 6230 6231 BPF_CALL_1(bpf_sys_close, u32, fd) 6232 { 6233 /* When bpf program calls this helper there should not be 6234 * an fdget() without matching completed fdput(). 6235 * This helper is allowed in the following callchain only: 6236 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close 6237 */ 6238 return close_fd(fd); 6239 } 6240 6241 static const struct bpf_func_proto bpf_sys_close_proto = { 6242 .func = bpf_sys_close, 6243 .gpl_only = false, 6244 .ret_type = RET_INTEGER, 6245 .arg1_type = ARG_ANYTHING, 6246 }; 6247 6248 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) 6249 { 6250 *res = 0; 6251 if (flags) 6252 return -EINVAL; 6253 6254 if (name_sz <= 1 || name[name_sz - 1]) 6255 return -EINVAL; 6256 6257 if (!bpf_dump_raw_ok(current_cred())) 6258 return -EPERM; 6259 6260 *res = kallsyms_lookup_name(name); 6261 return *res ? 0 : -ENOENT; 6262 } 6263 6264 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { 6265 .func = bpf_kallsyms_lookup_name, 6266 .gpl_only = false, 6267 .ret_type = RET_INTEGER, 6268 .arg1_type = ARG_PTR_TO_MEM, 6269 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 6270 .arg3_type = ARG_ANYTHING, 6271 .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_WRITE | MEM_ALIGNED, 6272 .arg4_size = sizeof(u64), 6273 }; 6274 6275 static const struct bpf_func_proto * 6276 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 6277 { 6278 switch (func_id) { 6279 case BPF_FUNC_sys_bpf: 6280 return !bpf_token_capable(prog->aux->token, CAP_PERFMON) 6281 ? NULL : &bpf_sys_bpf_proto; 6282 case BPF_FUNC_btf_find_by_name_kind: 6283 return &bpf_btf_find_by_name_kind_proto; 6284 case BPF_FUNC_sys_close: 6285 return &bpf_sys_close_proto; 6286 case BPF_FUNC_kallsyms_lookup_name: 6287 return &bpf_kallsyms_lookup_name_proto; 6288 default: 6289 return tracing_prog_func_proto(func_id, prog); 6290 } 6291 } 6292 6293 const struct bpf_verifier_ops bpf_syscall_verifier_ops = { 6294 .get_func_proto = syscall_prog_func_proto, 6295 .is_valid_access = syscall_prog_is_valid_access, 6296 }; 6297 6298 const struct bpf_prog_ops bpf_syscall_prog_ops = { 6299 .test_run = bpf_prog_test_run_syscall, 6300 }; 6301 6302 #ifdef CONFIG_SYSCTL 6303 static int bpf_stats_handler(const struct ctl_table *table, int write, 6304 void *buffer, size_t *lenp, loff_t *ppos) 6305 { 6306 struct static_key *key = (struct static_key *)table->data; 6307 static int saved_val; 6308 int val, ret; 6309 struct ctl_table tmp = { 6310 .data = &val, 6311 .maxlen = sizeof(val), 6312 .mode = table->mode, 6313 .extra1 = SYSCTL_ZERO, 6314 .extra2 = SYSCTL_ONE, 6315 }; 6316 6317 if (write && !capable(CAP_SYS_ADMIN)) 6318 return -EPERM; 6319 6320 mutex_lock(&bpf_stats_enabled_mutex); 6321 val = saved_val; 6322 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6323 if (write && !ret && val != saved_val) { 6324 if (val) 6325 static_key_slow_inc(key); 6326 else 6327 static_key_slow_dec(key); 6328 saved_val = val; 6329 } 6330 mutex_unlock(&bpf_stats_enabled_mutex); 6331 return ret; 6332 } 6333 6334 void __weak unpriv_ebpf_notify(int new_state) 6335 { 6336 } 6337 6338 static int bpf_unpriv_handler(const struct ctl_table *table, int write, 6339 void *buffer, size_t *lenp, loff_t *ppos) 6340 { 6341 int ret, unpriv_enable = *(int *)table->data; 6342 bool locked_state = unpriv_enable == 1; 6343 struct ctl_table tmp = *table; 6344 6345 if (write && !capable(CAP_SYS_ADMIN)) 6346 return -EPERM; 6347 6348 tmp.data = &unpriv_enable; 6349 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 6350 if (write && !ret) { 6351 if (locked_state && unpriv_enable != 1) 6352 return -EPERM; 6353 *(int *)table->data = unpriv_enable; 6354 } 6355 6356 if (write) 6357 unpriv_ebpf_notify(unpriv_enable); 6358 6359 return ret; 6360 } 6361 6362 static const struct ctl_table bpf_syscall_table[] = { 6363 { 6364 .procname = "unprivileged_bpf_disabled", 6365 .data = &sysctl_unprivileged_bpf_disabled, 6366 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), 6367 .mode = 0644, 6368 .proc_handler = bpf_unpriv_handler, 6369 .extra1 = SYSCTL_ZERO, 6370 .extra2 = SYSCTL_TWO, 6371 }, 6372 { 6373 .procname = "bpf_stats_enabled", 6374 .data = &bpf_stats_enabled_key.key, 6375 .mode = 0644, 6376 .proc_handler = bpf_stats_handler, 6377 }, 6378 }; 6379 6380 static int __init bpf_syscall_sysctl_init(void) 6381 { 6382 register_sysctl_init("kernel", bpf_syscall_table); 6383 return 0; 6384 } 6385 late_initcall(bpf_syscall_sysctl_init); 6386 #endif /* CONFIG_SYSCTL */ 6387