kernel/bpf/syscall.c

   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/btf.h>
  10 #include <linux/syscalls.h>
  11 #include <linux/slab.h>
  12 #include <linux/sched/signal.h>
  13 #include <linux/vmalloc.h>
  14 #include <linux/mmzone.h>
  15 #include <linux/anon_inodes.h>
  16 #include <linux/fdtable.h>
  17 #include <linux/file.h>
  18 #include <linux/fs.h>
  19 #include <linux/license.h>
  20 #include <linux/filter.h>
  21 #include <linux/kernel.h>
  22 #include <linux/idr.h>
  23 #include <linux/cred.h>
  24 #include <linux/timekeeping.h>
  25 #include <linux/ctype.h>
  26 #include <linux/nospec.h>
  27 #include <linux/audit.h>
  28 #include <uapi/linux/btf.h>
  29 #include <linux/pgtable.h>
  30 #include <linux/bpf_lsm.h>
  31 #include <linux/poll.h>
  32 #include <linux/bpf-netns.h>
  33 #include <linux/rcupdate_trace.h>
  34 #include <linux/memcontrol.h>
  35
  36 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
  37                           (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
  38                           (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
  39 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
  40 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
  41 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
  42                         IS_FD_HASH(map))
  43
  44 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
  45
  46 DEFINE_PER_CPU(int, bpf_prog_active);
  47 static DEFINE_IDR(prog_idr);
  48 static DEFINE_SPINLOCK(prog_idr_lock);
  49 static DEFINE_IDR(map_idr);
  50 static DEFINE_SPINLOCK(map_idr_lock);
  51 static DEFINE_IDR(link_idr);
  52 static DEFINE_SPINLOCK(link_idr_lock);
  53
  54 int sysctl_unprivileged_bpf_disabled __read_mostly =
  55         IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
  56
  57 static const struct bpf_map_ops * const bpf_map_types[] = {
  58 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
  59 #define BPF_MAP_TYPE(_id, _ops) \
  60         [_id] = &_ops,
  61 #define BPF_LINK_TYPE(_id, _name)
  62 #include <linux/bpf_types.h>
  63 #undef BPF_PROG_TYPE
  64 #undef BPF_MAP_TYPE
  65 #undef BPF_LINK_TYPE
  66 };
  67
  68 /*
  69  * If we're handed a bigger struct than we know of, ensure all the unknown bits
  70  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
  71  * we don't know about yet.
  72  *
  73  * There is a ToCToU between this function call and the following
  74  * copy_from_user() call. However, this is not a concern since this function is
  75  * meant to be a future-proofing of bits.
  76  */
  77 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
  78                              size_t expected_size,
  79                              size_t actual_size)
  80 {
  81         int res;
  82
  83         if (unlikely(actual_size > PAGE_SIZE))  /* silly large */
  84                 return -E2BIG;
  85
  86         if (actual_size <= expected_size)
  87                 return 0;
  88
  89         if (uaddr.is_kernel)
  90                 res = memchr_inv(uaddr.kernel + expected_size, 0,
  91                                  actual_size - expected_size) == NULL;
  92         else
  93                 res = check_zeroed_user(uaddr.user + expected_size,
  94                                         actual_size - expected_size);
  95         if (res < 0)
  96                 return res;
  97         return res ? 0 : -E2BIG;
  98 }
  99
 100 const struct bpf_map_ops bpf_map_offload_ops = {
 101         .map_meta_equal = bpf_map_meta_equal,
 102         .map_alloc = bpf_map_offload_map_alloc,
 103         .map_free = bpf_map_offload_map_free,
 104         .map_check_btf = map_check_no_btf,
 105 };
 106
 107 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
 108 {
 109         const struct bpf_map_ops *ops;
 110         u32 type = attr->map_type;
 111         struct bpf_map *map;
 112         int err;
 113
 114         if (type >= ARRAY_SIZE(bpf_map_types))
 115                 return ERR_PTR(-EINVAL);
 116         type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
 117         ops = bpf_map_types[type];
 118         if (!ops)
 119                 return ERR_PTR(-EINVAL);
 120
 121         if (ops->map_alloc_check) {
 122                 err = ops->map_alloc_check(attr);
 123                 if (err)
 124                         return ERR_PTR(err);
 125         }
 126         if (attr->map_ifindex)
 127                 ops = &bpf_map_offload_ops;
 128         map = ops->map_alloc(attr);
 129         if (IS_ERR(map))
 130                 return map;
 131         map->ops = ops;
 132         map->map_type = type;
 133         return map;
 134 }
 135
 136 static void bpf_map_write_active_inc(struct bpf_map *map)
 137 {
 138         atomic64_inc(&map->writecnt);
 139 }
 140
 141 static void bpf_map_write_active_dec(struct bpf_map *map)
 142 {
 143         atomic64_dec(&map->writecnt);
 144 }
 145
 146 bool bpf_map_write_active(const struct bpf_map *map)
 147 {
 148         return atomic64_read(&map->writecnt) != 0;
 149 }
 150
 151 static u32 bpf_map_value_size(const struct bpf_map *map)
 152 {
 153         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 154             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
 155             map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 156             map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 157                 return round_up(map->value_size, 8) * num_possible_cpus();
 158         else if (IS_FD_MAP(map))
 159                 return sizeof(u32);
 160         else
 161                 return  map->value_size;
 162 }
 163
 164 static void maybe_wait_bpf_programs(struct bpf_map *map)
 165 {
 166         /* Wait for any running BPF programs to complete so that
 167          * userspace, when we return to it, knows that all programs
 168          * that could be running use the new map value.
 169          */
 170         if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
 171             map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
 172                 synchronize_rcu();
 173 }
 174
 175 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
 176                                 void *value, __u64 flags)
 177 {
 178         int err;
 179
 180         /* Need to create a kthread, thus must support schedule */
 181         if (bpf_map_is_dev_bound(map)) {
 182                 return bpf_map_offload_update_elem(map, key, value, flags);
 183         } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
 184                    map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
 185                 return map->ops->map_update_elem(map, key, value, flags);
 186         } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
 187                    map->map_type == BPF_MAP_TYPE_SOCKMAP) {
 188                 return sock_map_update_elem_sys(map, key, value, flags);
 189         } else if (IS_FD_PROG_ARRAY(map)) {
 190                 return bpf_fd_array_map_update_elem(map, f.file, key, value,
 191                                                     flags);
 192         }
 193
 194         bpf_disable_instrumentation();
 195         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 196             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 197                 err = bpf_percpu_hash_update(map, key, value, flags);
 198         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 199                 err = bpf_percpu_array_update(map, key, value, flags);
 200         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 201                 err = bpf_percpu_cgroup_storage_update(map, key, value,
 202                                                        flags);
 203         } else if (IS_FD_ARRAY(map)) {
 204                 rcu_read_lock();
 205                 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
 206                                                    flags);
 207                 rcu_read_unlock();
 208         } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
 209                 rcu_read_lock();
 210                 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
 211                                                   flags);
 212                 rcu_read_unlock();
 213         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 214                 /* rcu_read_lock() is not needed */
 215                 err = bpf_fd_reuseport_array_update_elem(map, key, value,
 216                                                          flags);
 217         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 218                    map->map_type == BPF_MAP_TYPE_STACK ||
 219                    map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
 220                 err = map->ops->map_push_elem(map, value, flags);
 221         } else {
 222                 rcu_read_lock();
 223                 err = map->ops->map_update_elem(map, key, value, flags);
 224                 rcu_read_unlock();
 225         }
 226         bpf_enable_instrumentation();
 227         maybe_wait_bpf_programs(map);
 228
 229         return err;
 230 }
 231
 232 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
 233                               __u64 flags)
 234 {
 235         void *ptr;
 236         int err;
 237
 238         if (bpf_map_is_dev_bound(map))
 239                 return bpf_map_offload_lookup_elem(map, key, value);
 240
 241         bpf_disable_instrumentation();
 242         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 243             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 244                 err = bpf_percpu_hash_copy(map, key, value);
 245         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 246                 err = bpf_percpu_array_copy(map, key, value);
 247         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 248                 err = bpf_percpu_cgroup_storage_copy(map, key, value);
 249         } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
 250                 err = bpf_stackmap_copy(map, key, value);
 251         } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
 252                 err = bpf_fd_array_map_lookup_elem(map, key, value);
 253         } else if (IS_FD_HASH(map)) {
 254                 err = bpf_fd_htab_map_lookup_elem(map, key, value);
 255         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 256                 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
 257         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 258                    map->map_type == BPF_MAP_TYPE_STACK ||
 259                    map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
 260                 err = map->ops->map_peek_elem(map, value);
 261         } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
 262                 /* struct_ops map requires directly updating "value" */
 263                 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
 264         } else {
 265                 rcu_read_lock();
 266                 if (map->ops->map_lookup_elem_sys_only)
 267                         ptr = map->ops->map_lookup_elem_sys_only(map, key);
 268                 else
 269                         ptr = map->ops->map_lookup_elem(map, key);
 270                 if (IS_ERR(ptr)) {
 271                         err = PTR_ERR(ptr);
 272                 } else if (!ptr) {
 273                         err = -ENOENT;
 274                 } else {
 275                         err = 0;
 276                         if (flags & BPF_F_LOCK)
 277                                 /* lock 'ptr' and copy everything but lock */
 278                                 copy_map_value_locked(map, value, ptr, true);
 279                         else
 280                                 copy_map_value(map, value, ptr);
 281                         /* mask lock and timer, since value wasn't zero inited */
 282                         check_and_init_map_value(map, value);
 283                 }
 284                 rcu_read_unlock();
 285         }
 286
 287         bpf_enable_instrumentation();
 288         maybe_wait_bpf_programs(map);
 289
 290         return err;
 291 }
 292
 293 /* Please, do not use this function outside from the map creation path
 294  * (e.g. in map update path) without taking care of setting the active
 295  * memory cgroup (see at bpf_map_kmalloc_node() for example).
 296  */
 297 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
 298 {
 299         /* We really just want to fail instead of triggering OOM killer
 300          * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
 301          * which is used for lower order allocation requests.
 302          *
 303          * It has been observed that higher order allocation requests done by
 304          * vmalloc with __GFP_NORETRY being set might fail due to not trying
 305          * to reclaim memory from the page cache, thus we set
 306          * __GFP_RETRY_MAYFAIL to avoid such situations.
 307          */
 308
 309         const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
 310         unsigned int flags = 0;
 311         unsigned long align = 1;
 312         void *area;
 313
 314         if (size >= SIZE_MAX)
 315                 return NULL;
 316
 317         /* kmalloc()'ed memory can't be mmap()'ed */
 318         if (mmapable) {
 319                 BUG_ON(!PAGE_ALIGNED(size));
 320                 align = SHMLBA;
 321                 flags = VM_USERMAP;
 322         } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
 323                 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
 324                                     numa_node);
 325                 if (area != NULL)
 326                         return area;
 327         }
 328
 329         return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
 330                         gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
 331                         flags, numa_node, __builtin_return_address(0));
 332 }
 333
 334 void *bpf_map_area_alloc(u64 size, int numa_node)
 335 {
 336         return __bpf_map_area_alloc(size, numa_node, false);
 337 }
 338
 339 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
 340 {
 341         return __bpf_map_area_alloc(size, numa_node, true);
 342 }
 343
 344 void bpf_map_area_free(void *area)
 345 {
 346         kvfree(area);
 347 }
 348
 349 static u32 bpf_map_flags_retain_permanent(u32 flags)
 350 {
 351         /* Some map creation flags are not tied to the map object but
 352          * rather to the map fd instead, so they have no meaning upon
 353          * map object inspection since multiple file descriptors with
 354          * different (access) properties can exist here. Thus, given
 355          * this has zero meaning for the map itself, lets clear these
 356          * from here.
 357          */
 358         return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
 359 }
 360
 361 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 362 {
 363         map->map_type = attr->map_type;
 364         map->key_size = attr->key_size;
 365         map->value_size = attr->value_size;
 366         map->max_entries = attr->max_entries;
 367         map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
 368         map->numa_node = bpf_map_attr_numa_node(attr);
 369         map->map_extra = attr->map_extra;
 370 }
 371
 372 static int bpf_map_alloc_id(struct bpf_map *map)
 373 {
 374         int id;
 375
 376         idr_preload(GFP_KERNEL);
 377         spin_lock_bh(&map_idr_lock);
 378         id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
 379         if (id > 0)
 380                 map->id = id;
 381         spin_unlock_bh(&map_idr_lock);
 382         idr_preload_end();
 383
 384         if (WARN_ON_ONCE(!id))
 385                 return -ENOSPC;
 386
 387         return id > 0 ? 0 : id;
 388 }
 389
 390 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
 391 {
 392         unsigned long flags;
 393
 394         /* Offloaded maps are removed from the IDR store when their device
 395          * disappears - even if someone holds an fd to them they are unusable,
 396          * the memory is gone, all ops will fail; they are simply waiting for
 397          * refcnt to drop to be freed.
 398          */
 399         if (!map->id)
 400                 return;
 401
 402         if (do_idr_lock)
 403                 spin_lock_irqsave(&map_idr_lock, flags);
 404         else
 405                 __acquire(&map_idr_lock);
 406
 407         idr_remove(&map_idr, map->id);
 408         map->id = 0;
 409
 410         if (do_idr_lock)
 411                 spin_unlock_irqrestore(&map_idr_lock, flags);
 412         else
 413                 __release(&map_idr_lock);
 414 }
 415
 416 #ifdef CONFIG_MEMCG_KMEM
 417 static void bpf_map_save_memcg(struct bpf_map *map)
 418 {
 419         map->memcg = get_mem_cgroup_from_mm(current->mm);
 420 }
 421
 422 static void bpf_map_release_memcg(struct bpf_map *map)
 423 {
 424         mem_cgroup_put(map->memcg);
 425 }
 426
 427 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
 428                            int node)
 429 {
 430         struct mem_cgroup *old_memcg;
 431         void *ptr;
 432
 433         old_memcg = set_active_memcg(map->memcg);
 434         ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
 435         set_active_memcg(old_memcg);
 436
 437         return ptr;
 438 }
 439
 440 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
 441 {
 442         struct mem_cgroup *old_memcg;
 443         void *ptr;
 444
 445         old_memcg = set_active_memcg(map->memcg);
 446         ptr = kzalloc(size, flags | __GFP_ACCOUNT);
 447         set_active_memcg(old_memcg);
 448
 449         return ptr;
 450 }
 451
 452 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
 453                                     size_t align, gfp_t flags)
 454 {
 455         struct mem_cgroup *old_memcg;
 456         void __percpu *ptr;
 457
 458         old_memcg = set_active_memcg(map->memcg);
 459         ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
 460         set_active_memcg(old_memcg);
 461
 462         return ptr;
 463 }
 464
 465 #else
 466 static void bpf_map_save_memcg(struct bpf_map *map)
 467 {
 468 }
 469
 470 static void bpf_map_release_memcg(struct bpf_map *map)
 471 {
 472 }
 473 #endif
 474
 475 /* called from workqueue */
 476 static void bpf_map_free_deferred(struct work_struct *work)
 477 {
 478         struct bpf_map *map = container_of(work, struct bpf_map, work);
 479
 480         security_bpf_map_free(map);
 481         bpf_map_release_memcg(map);
 482         /* implementation dependent freeing */
 483         map->ops->map_free(map);
 484 }
 485
 486 static void bpf_map_put_uref(struct bpf_map *map)
 487 {
 488         if (atomic64_dec_and_test(&map->usercnt)) {
 489                 if (map->ops->map_release_uref)
 490                         map->ops->map_release_uref(map);
 491         }
 492 }
 493
 494 /* decrement map refcnt and schedule it for freeing via workqueue
 495  * (unrelying map implementation ops->map_free() might sleep)
 496  */
 497 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
 498 {
 499         if (atomic64_dec_and_test(&map->refcnt)) {
 500                 /* bpf_map_free_id() must be called first */
 501                 bpf_map_free_id(map, do_idr_lock);
 502                 btf_put(map->btf);
 503                 INIT_WORK(&map->work, bpf_map_free_deferred);
 504                 schedule_work(&map->work);
 505         }
 506 }
 507
 508 void bpf_map_put(struct bpf_map *map)
 509 {
 510         __bpf_map_put(map, true);
 511 }
 512 EXPORT_SYMBOL_GPL(bpf_map_put);
 513
 514 void bpf_map_put_with_uref(struct bpf_map *map)
 515 {
 516         bpf_map_put_uref(map);
 517         bpf_map_put(map);
 518 }
 519
 520 static int bpf_map_release(struct inode *inode, struct file *filp)
 521 {
 522         struct bpf_map *map = filp->private_data;
 523
 524         if (map->ops->map_release)
 525                 map->ops->map_release(map, filp);
 526
 527         bpf_map_put_with_uref(map);
 528         return 0;
 529 }
 530
 531 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
 532 {
 533         fmode_t mode = f.file->f_mode;
 534
 535         /* Our file permissions may have been overridden by global
 536          * map permissions facing syscall side.
 537          */
 538         if (READ_ONCE(map->frozen))
 539                 mode &= ~FMODE_CAN_WRITE;
 540         return mode;
 541 }
 542
 543 #ifdef CONFIG_PROC_FS
 544 /* Provides an approximation of the map's memory footprint.
 545  * Used only to provide a backward compatibility and display
 546  * a reasonable "memlock" info.
 547  */
 548 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
 549 {
 550         unsigned long size;
 551
 552         size = round_up(map->key_size + bpf_map_value_size(map), 8);
 553
 554         return round_up(map->max_entries * size, PAGE_SIZE);
 555 }
 556
 557 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 558 {
 559         const struct bpf_map *map = filp->private_data;
 560         const struct bpf_array *array;
 561         u32 type = 0, jited = 0;
 562
 563         if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
 564                 array = container_of(map, struct bpf_array, map);
 565                 spin_lock(&array->aux->owner.lock);
 566                 type  = array->aux->owner.type;
 567                 jited = array->aux->owner.jited;
 568                 spin_unlock(&array->aux->owner.lock);
 569         }
 570
 571         seq_printf(m,
 572                    "map_type:\t%u\n"
 573                    "key_size:\t%u\n"
 574                    "value_size:\t%u\n"
 575                    "max_entries:\t%u\n"
 576                    "map_flags:\t%#x\n"
 577                    "map_extra:\t%#llx\n"
 578                    "memlock:\t%lu\n"
 579                    "map_id:\t%u\n"
 580                    "frozen:\t%u\n",
 581                    map->map_type,
 582                    map->key_size,
 583                    map->value_size,
 584                    map->max_entries,
 585                    map->map_flags,
 586                    (unsigned long long)map->map_extra,
 587                    bpf_map_memory_footprint(map),
 588                    map->id,
 589                    READ_ONCE(map->frozen));
 590         if (type) {
 591                 seq_printf(m, "owner_prog_type:\t%u\n", type);
 592                 seq_printf(m, "owner_jited:\t%u\n", jited);
 593         }
 594 }
 595 #endif
 596
 597 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
 598                               loff_t *ppos)
 599 {
 600         /* We need this handler such that alloc_file() enables
 601          * f_mode with FMODE_CAN_READ.
 602          */
 603         return -EINVAL;
 604 }
 605
 606 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
 607                                size_t siz, loff_t *ppos)
 608 {
 609         /* We need this handler such that alloc_file() enables
 610          * f_mode with FMODE_CAN_WRITE.
 611          */
 612         return -EINVAL;
 613 }
 614
 615 /* called for any extra memory-mapped regions (except initial) */
 616 static void bpf_map_mmap_open(struct vm_area_struct *vma)
 617 {
 618         struct bpf_map *map = vma->vm_file->private_data;
 619
 620         if (vma->vm_flags & VM_MAYWRITE)
 621                 bpf_map_write_active_inc(map);
 622 }
 623
 624 /* called for all unmapped memory region (including initial) */
 625 static void bpf_map_mmap_close(struct vm_area_struct *vma)
 626 {
 627         struct bpf_map *map = vma->vm_file->private_data;
 628
 629         if (vma->vm_flags & VM_MAYWRITE)
 630                 bpf_map_write_active_dec(map);
 631 }
 632
 633 static const struct vm_operations_struct bpf_map_default_vmops = {
 634         .open           = bpf_map_mmap_open,
 635         .close          = bpf_map_mmap_close,
 636 };
 637
 638 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
 639 {
 640         struct bpf_map *map = filp->private_data;
 641         int err;
 642
 643         if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
 644             map_value_has_timer(map))
 645                 return -ENOTSUPP;
 646
 647         if (!(vma->vm_flags & VM_SHARED))
 648                 return -EINVAL;
 649
 650         mutex_lock(&map->freeze_mutex);
 651
 652         if (vma->vm_flags & VM_WRITE) {
 653                 if (map->frozen) {
 654                         err = -EPERM;
 655                         goto out;
 656                 }
 657                 /* map is meant to be read-only, so do not allow mapping as
 658                  * writable, because it's possible to leak a writable page
 659                  * reference and allows user-space to still modify it after
 660                  * freezing, while verifier will assume contents do not change
 661                  */
 662                 if (map->map_flags & BPF_F_RDONLY_PROG) {
 663                         err = -EACCES;
 664                         goto out;
 665                 }
 666         }
 667
 668         /* set default open/close callbacks */
 669         vma->vm_ops = &bpf_map_default_vmops;
 670         vma->vm_private_data = map;
 671         vma->vm_flags &= ~VM_MAYEXEC;
 672         if (!(vma->vm_flags & VM_WRITE))
 673                 /* disallow re-mapping with PROT_WRITE */
 674                 vma->vm_flags &= ~VM_MAYWRITE;
 675
 676         err = map->ops->map_mmap(map, vma);
 677         if (err)
 678                 goto out;
 679
 680         if (vma->vm_flags & VM_MAYWRITE)
 681                 bpf_map_write_active_inc(map);
 682 out:
 683         mutex_unlock(&map->freeze_mutex);
 684         return err;
 685 }
 686
 687 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
 688 {
 689         struct bpf_map *map = filp->private_data;
 690
 691         if (map->ops->map_poll)
 692                 return map->ops->map_poll(map, filp, pts);
 693
 694         return EPOLLERR;
 695 }
 696
 697 const struct file_operations bpf_map_fops = {
 698 #ifdef CONFIG_PROC_FS
 699         .show_fdinfo    = bpf_map_show_fdinfo,
 700 #endif
 701         .release        = bpf_map_release,
 702         .read           = bpf_dummy_read,
 703         .write          = bpf_dummy_write,
 704         .mmap           = bpf_map_mmap,
 705         .poll           = bpf_map_poll,
 706 };
 707
 708 int bpf_map_new_fd(struct bpf_map *map, int flags)
 709 {
 710         int ret;
 711
 712         ret = security_bpf_map(map, OPEN_FMODE(flags));
 713         if (ret < 0)
 714                 return ret;
 715
 716         return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
 717                                 flags | O_CLOEXEC);
 718 }
 719
 720 int bpf_get_file_flag(int flags)
 721 {
 722         if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
 723                 return -EINVAL;
 724         if (flags & BPF_F_RDONLY)
 725                 return O_RDONLY;
 726         if (flags & BPF_F_WRONLY)
 727                 return O_WRONLY;
 728         return O_RDWR;
 729 }
 730
 731 /* helper macro to check that unused fields 'union bpf_attr' are zero */
 732 #define CHECK_ATTR(CMD) \
 733         memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
 734                    sizeof(attr->CMD##_LAST_FIELD), 0, \
 735                    sizeof(*attr) - \
 736                    offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
 737                    sizeof(attr->CMD##_LAST_FIELD)) != NULL
 738
 739 /* dst and src must have at least "size" number of bytes.
 740  * Return strlen on success and < 0 on error.
 741  */
 742 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
 743 {
 744         const char *end = src + size;
 745         const char *orig_src = src;
 746
 747         memset(dst, 0, size);
 748         /* Copy all isalnum(), '_' and '.' chars. */
 749         while (src < end && *src) {
 750                 if (!isalnum(*src) &&
 751                     *src != '_' && *src != '.')
 752                         return -EINVAL;
 753                 *dst++ = *src++;
 754         }
 755
 756         /* No '\0' found in "size" number of bytes */
 757         if (src == end)
 758                 return -EINVAL;
 759
 760         return src - orig_src;
 761 }
 762
 763 int map_check_no_btf(const struct bpf_map *map,
 764                      const struct btf *btf,
 765                      const struct btf_type *key_type,
 766                      const struct btf_type *value_type)
 767 {
 768         return -ENOTSUPP;
 769 }
 770
 771 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 772                          u32 btf_key_id, u32 btf_value_id)
 773 {
 774         const struct btf_type *key_type, *value_type;
 775         u32 key_size, value_size;
 776         int ret = 0;
 777
 778         /* Some maps allow key to be unspecified. */
 779         if (btf_key_id) {
 780                 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
 781                 if (!key_type || key_size != map->key_size)
 782                         return -EINVAL;
 783         } else {
 784                 key_type = btf_type_by_id(btf, 0);
 785                 if (!map->ops->map_check_btf)
 786                         return -EINVAL;
 787         }
 788
 789         value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
 790         if (!value_type || value_size != map->value_size)
 791                 return -EINVAL;
 792
 793         map->spin_lock_off = btf_find_spin_lock(btf, value_type);
 794
 795         if (map_value_has_spin_lock(map)) {
 796                 if (map->map_flags & BPF_F_RDONLY_PROG)
 797                         return -EACCES;
 798                 if (map->map_type != BPF_MAP_TYPE_HASH &&
 799                     map->map_type != BPF_MAP_TYPE_ARRAY &&
 800                     map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
 801                     map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
 802                     map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
 803                     map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
 804                         return -ENOTSUPP;
 805                 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
 806                     map->value_size) {
 807                         WARN_ONCE(1,
 808                                   "verifier bug spin_lock_off %d value_size %d\n",
 809                                   map->spin_lock_off, map->value_size);
 810                         return -EFAULT;
 811                 }
 812         }
 813
 814         map->timer_off = btf_find_timer(btf, value_type);
 815         if (map_value_has_timer(map)) {
 816                 if (map->map_flags & BPF_F_RDONLY_PROG)
 817                         return -EACCES;
 818                 if (map->map_type != BPF_MAP_TYPE_HASH &&
 819                     map->map_type != BPF_MAP_TYPE_LRU_HASH &&
 820                     map->map_type != BPF_MAP_TYPE_ARRAY)
 821                         return -EOPNOTSUPP;
 822         }
 823
 824         if (map->ops->map_check_btf)
 825                 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
 826
 827         return ret;
 828 }
 829
 830 #define BPF_MAP_CREATE_LAST_FIELD map_extra
 831 /* called via syscall */
 832 static int map_create(union bpf_attr *attr)
 833 {
 834         int numa_node = bpf_map_attr_numa_node(attr);
 835         struct bpf_map *map;
 836         int f_flags;
 837         int err;
 838
 839         err = CHECK_ATTR(BPF_MAP_CREATE);
 840         if (err)
 841                 return -EINVAL;
 842
 843         if (attr->btf_vmlinux_value_type_id) {
 844                 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
 845                     attr->btf_key_type_id || attr->btf_value_type_id)
 846                         return -EINVAL;
 847         } else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
 848                 return -EINVAL;
 849         }
 850
 851         if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
 852             attr->map_extra != 0)
 853                 return -EINVAL;
 854
 855         f_flags = bpf_get_file_flag(attr->map_flags);
 856         if (f_flags < 0)
 857                 return f_flags;
 858
 859         if (numa_node != NUMA_NO_NODE &&
 860             ((unsigned int)numa_node >= nr_node_ids ||
 861              !node_online(numa_node)))
 862                 return -EINVAL;
 863
 864         /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
 865         map = find_and_alloc_map(attr);
 866         if (IS_ERR(map))
 867                 return PTR_ERR(map);
 868
 869         err = bpf_obj_name_cpy(map->name, attr->map_name,
 870                                sizeof(attr->map_name));
 871         if (err < 0)
 872                 goto free_map;
 873
 874         atomic64_set(&map->refcnt, 1);
 875         atomic64_set(&map->usercnt, 1);
 876         mutex_init(&map->freeze_mutex);
 877
 878         map->spin_lock_off = -EINVAL;
 879         map->timer_off = -EINVAL;
 880         if (attr->btf_key_type_id || attr->btf_value_type_id ||
 881             /* Even the map's value is a kernel's struct,
 882              * the bpf_prog.o must have BTF to begin with
 883              * to figure out the corresponding kernel's
 884              * counter part.  Thus, attr->btf_fd has
 885              * to be valid also.
 886              */
 887             attr->btf_vmlinux_value_type_id) {
 888                 struct btf *btf;
 889
 890                 btf = btf_get_by_fd(attr->btf_fd);
 891                 if (IS_ERR(btf)) {
 892                         err = PTR_ERR(btf);
 893                         goto free_map;
 894                 }
 895                 if (btf_is_kernel(btf)) {
 896                         btf_put(btf);
 897                         err = -EACCES;
 898                         goto free_map;
 899                 }
 900                 map->btf = btf;
 901
 902                 if (attr->btf_value_type_id) {
 903                         err = map_check_btf(map, btf, attr->btf_key_type_id,
 904                                             attr->btf_value_type_id);
 905                         if (err)
 906                                 goto free_map;
 907                 }
 908
 909                 map->btf_key_type_id = attr->btf_key_type_id;
 910                 map->btf_value_type_id = attr->btf_value_type_id;
 911                 map->btf_vmlinux_value_type_id =
 912                         attr->btf_vmlinux_value_type_id;
 913         }
 914
 915         err = security_bpf_map_alloc(map);
 916         if (err)
 917                 goto free_map;
 918
 919         err = bpf_map_alloc_id(map);
 920         if (err)
 921                 goto free_map_sec;
 922
 923         bpf_map_save_memcg(map);
 924
 925         err = bpf_map_new_fd(map, f_flags);
 926         if (err < 0) {
 927                 /* failed to allocate fd.
 928                  * bpf_map_put_with_uref() is needed because the above
 929                  * bpf_map_alloc_id() has published the map
 930                  * to the userspace and the userspace may
 931                  * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
 932                  */
 933                 bpf_map_put_with_uref(map);
 934                 return err;
 935         }
 936
 937         return err;
 938
 939 free_map_sec:
 940         security_bpf_map_free(map);
 941 free_map:
 942         btf_put(map->btf);
 943         map->ops->map_free(map);
 944         return err;
 945 }
 946
 947 /* if error is returned, fd is released.
 948  * On success caller should complete fd access with matching fdput()
 949  */
 950 struct bpf_map *__bpf_map_get(struct fd f)
 951 {
 952         if (!f.file)
 953                 return ERR_PTR(-EBADF);
 954         if (f.file->f_op != &bpf_map_fops) {
 955                 fdput(f);
 956                 return ERR_PTR(-EINVAL);
 957         }
 958
 959         return f.file->private_data;
 960 }
 961
 962 void bpf_map_inc(struct bpf_map *map)
 963 {
 964         atomic64_inc(&map->refcnt);
 965 }
 966 EXPORT_SYMBOL_GPL(bpf_map_inc);
 967
 968 void bpf_map_inc_with_uref(struct bpf_map *map)
 969 {
 970         atomic64_inc(&map->refcnt);
 971         atomic64_inc(&map->usercnt);
 972 }
 973 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
 974
 975 struct bpf_map *bpf_map_get(u32 ufd)
 976 {
 977         struct fd f = fdget(ufd);
 978         struct bpf_map *map;
 979
 980         map = __bpf_map_get(f);
 981         if (IS_ERR(map))
 982                 return map;
 983
 984         bpf_map_inc(map);
 985         fdput(f);
 986
 987         return map;
 988 }
 989
 990 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
 991 {
 992         struct fd f = fdget(ufd);
 993         struct bpf_map *map;
 994
 995         map = __bpf_map_get(f);
 996         if (IS_ERR(map))
 997                 return map;
 998
 999         bpf_map_inc_with_uref(map);
1000         fdput(f);
1001
1002         return map;
1003 }
1004
1005 /* map_idr_lock should have been held */
1006 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
1007 {
1008         int refold;
1009
1010         refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1011         if (!refold)
1012                 return ERR_PTR(-ENOENT);
1013         if (uref)
1014                 atomic64_inc(&map->usercnt);
1015
1016         return map;
1017 }
1018
1019 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1020 {
1021         spin_lock_bh(&map_idr_lock);
1022         map = __bpf_map_inc_not_zero(map, false);
1023         spin_unlock_bh(&map_idr_lock);
1024
1025         return map;
1026 }
1027 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1028
1029 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1030 {
1031         return -ENOTSUPP;
1032 }
1033
1034 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1035 {
1036         if (key_size)
1037                 return vmemdup_user(ukey, key_size);
1038
1039         if (ukey)
1040                 return ERR_PTR(-EINVAL);
1041
1042         return NULL;
1043 }
1044
1045 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1046 {
1047         if (key_size)
1048                 return kvmemdup_bpfptr(ukey, key_size);
1049
1050         if (!bpfptr_is_null(ukey))
1051                 return ERR_PTR(-EINVAL);
1052
1053         return NULL;
1054 }
1055
1056 /* last field in 'union bpf_attr' used by this command */
1057 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1058
1059 static int map_lookup_elem(union bpf_attr *attr)
1060 {
1061         void __user *ukey = u64_to_user_ptr(attr->key);
1062         void __user *uvalue = u64_to_user_ptr(attr->value);
1063         int ufd = attr->map_fd;
1064         struct bpf_map *map;
1065         void *key, *value;
1066         u32 value_size;
1067         struct fd f;
1068         int err;
1069
1070         if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1071                 return -EINVAL;
1072
1073         if (attr->flags & ~BPF_F_LOCK)
1074                 return -EINVAL;
1075
1076         f = fdget(ufd);
1077         map = __bpf_map_get(f);
1078         if (IS_ERR(map))
1079                 return PTR_ERR(map);
1080         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1081                 err = -EPERM;
1082                 goto err_put;
1083         }
1084
1085         if ((attr->flags & BPF_F_LOCK) &&
1086             !map_value_has_spin_lock(map)) {
1087                 err = -EINVAL;
1088                 goto err_put;
1089         }
1090
1091         key = __bpf_copy_key(ukey, map->key_size);
1092         if (IS_ERR(key)) {
1093                 err = PTR_ERR(key);
1094                 goto err_put;
1095         }
1096
1097         value_size = bpf_map_value_size(map);
1098
1099         err = -ENOMEM;
1100         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1101         if (!value)
1102                 goto free_key;
1103
1104         if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1105                 if (copy_from_user(value, uvalue, value_size))
1106                         err = -EFAULT;
1107                 else
1108                         err = bpf_map_copy_value(map, key, value, attr->flags);
1109                 goto free_value;
1110         }
1111
1112         err = bpf_map_copy_value(map, key, value, attr->flags);
1113         if (err)
1114                 goto free_value;
1115
1116         err = -EFAULT;
1117         if (copy_to_user(uvalue, value, value_size) != 0)
1118                 goto free_value;
1119
1120         err = 0;
1121
1122 free_value:
1123         kvfree(value);
1124 free_key:
1125         kvfree(key);
1126 err_put:
1127         fdput(f);
1128         return err;
1129 }
1130
1131
1132 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1133
1134 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1135 {
1136         bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1137         bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1138         int ufd = attr->map_fd;
1139         struct bpf_map *map;
1140         void *key, *value;
1141         u32 value_size;
1142         struct fd f;
1143         int err;
1144
1145         if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1146                 return -EINVAL;
1147
1148         f = fdget(ufd);
1149         map = __bpf_map_get(f);
1150         if (IS_ERR(map))
1151                 return PTR_ERR(map);
1152         bpf_map_write_active_inc(map);
1153         if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1154                 err = -EPERM;
1155                 goto err_put;
1156         }
1157
1158         if ((attr->flags & BPF_F_LOCK) &&
1159             !map_value_has_spin_lock(map)) {
1160                 err = -EINVAL;
1161                 goto err_put;
1162         }
1163
1164         key = ___bpf_copy_key(ukey, map->key_size);
1165         if (IS_ERR(key)) {
1166                 err = PTR_ERR(key);
1167                 goto err_put;
1168         }
1169
1170         value_size = bpf_map_value_size(map);
1171
1172         err = -ENOMEM;
1173         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1174         if (!value)
1175                 goto free_key;
1176
1177         err = -EFAULT;
1178         if (copy_from_bpfptr(value, uvalue, value_size) != 0)
1179                 goto free_value;
1180
1181         err = bpf_map_update_value(map, f, key, value, attr->flags);
1182
1183 free_value:
1184         kvfree(value);
1185 free_key:
1186         kvfree(key);
1187 err_put:
1188         bpf_map_write_active_dec(map);
1189         fdput(f);
1190         return err;
1191 }
1192
1193 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1194
1195 static int map_delete_elem(union bpf_attr *attr)
1196 {
1197         void __user *ukey = u64_to_user_ptr(attr->key);
1198         int ufd = attr->map_fd;
1199         struct bpf_map *map;
1200         struct fd f;
1201         void *key;
1202         int err;
1203
1204         if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1205                 return -EINVAL;
1206
1207         f = fdget(ufd);
1208         map = __bpf_map_get(f);
1209         if (IS_ERR(map))
1210                 return PTR_ERR(map);
1211         bpf_map_write_active_inc(map);
1212         if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1213                 err = -EPERM;
1214                 goto err_put;
1215         }
1216
1217         key = __bpf_copy_key(ukey, map->key_size);
1218         if (IS_ERR(key)) {
1219                 err = PTR_ERR(key);
1220                 goto err_put;
1221         }
1222
1223         if (bpf_map_is_dev_bound(map)) {
1224                 err = bpf_map_offload_delete_elem(map, key);
1225                 goto out;
1226         } else if (IS_FD_PROG_ARRAY(map) ||
1227                    map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1228                 /* These maps require sleepable context */
1229                 err = map->ops->map_delete_elem(map, key);
1230                 goto out;
1231         }
1232
1233         bpf_disable_instrumentation();
1234         rcu_read_lock();
1235         err = map->ops->map_delete_elem(map, key);
1236         rcu_read_unlock();
1237         bpf_enable_instrumentation();
1238         maybe_wait_bpf_programs(map);
1239 out:
1240         kvfree(key);
1241 err_put:
1242         bpf_map_write_active_dec(map);
1243         fdput(f);
1244         return err;
1245 }
1246
1247 /* last field in 'union bpf_attr' used by this command */
1248 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1249
1250 static int map_get_next_key(union bpf_attr *attr)
1251 {
1252         void __user *ukey = u64_to_user_ptr(attr->key);
1253         void __user *unext_key = u64_to_user_ptr(attr->next_key);
1254         int ufd = attr->map_fd;
1255         struct bpf_map *map;
1256         void *key, *next_key;
1257         struct fd f;
1258         int err;
1259
1260         if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1261                 return -EINVAL;
1262
1263         f = fdget(ufd);
1264         map = __bpf_map_get(f);
1265         if (IS_ERR(map))
1266                 return PTR_ERR(map);
1267         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1268                 err = -EPERM;
1269                 goto err_put;
1270         }
1271
1272         if (ukey) {
1273                 key = __bpf_copy_key(ukey, map->key_size);
1274                 if (IS_ERR(key)) {
1275                         err = PTR_ERR(key);
1276                         goto err_put;
1277                 }
1278         } else {
1279                 key = NULL;
1280         }
1281
1282         err = -ENOMEM;
1283         next_key = kvmalloc(map->key_size, GFP_USER);
1284         if (!next_key)
1285                 goto free_key;
1286
1287         if (bpf_map_is_dev_bound(map)) {
1288                 err = bpf_map_offload_get_next_key(map, key, next_key);
1289                 goto out;
1290         }
1291
1292         rcu_read_lock();
1293         err = map->ops->map_get_next_key(map, key, next_key);
1294         rcu_read_unlock();
1295 out:
1296         if (err)
1297                 goto free_next_key;
1298
1299         err = -EFAULT;
1300         if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1301                 goto free_next_key;
1302
1303         err = 0;
1304
1305 free_next_key:
1306         kvfree(next_key);
1307 free_key:
1308         kvfree(key);
1309 err_put:
1310         fdput(f);
1311         return err;
1312 }
1313
1314 int generic_map_delete_batch(struct bpf_map *map,
1315                              const union bpf_attr *attr,
1316                              union bpf_attr __user *uattr)
1317 {
1318         void __user *keys = u64_to_user_ptr(attr->batch.keys);
1319         u32 cp, max_count;
1320         int err = 0;
1321         void *key;
1322
1323         if (attr->batch.elem_flags & ~BPF_F_LOCK)
1324                 return -EINVAL;
1325
1326         if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1327             !map_value_has_spin_lock(map)) {
1328                 return -EINVAL;
1329         }
1330
1331         max_count = attr->batch.count;
1332         if (!max_count)
1333                 return 0;
1334
1335         key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1336         if (!key)
1337                 return -ENOMEM;
1338
1339         for (cp = 0; cp < max_count; cp++) {
1340                 err = -EFAULT;
1341                 if (copy_from_user(key, keys + cp * map->key_size,
1342                                    map->key_size))
1343                         break;
1344
1345                 if (bpf_map_is_dev_bound(map)) {
1346                         err = bpf_map_offload_delete_elem(map, key);
1347                         break;
1348                 }
1349
1350                 bpf_disable_instrumentation();
1351                 rcu_read_lock();
1352                 err = map->ops->map_delete_elem(map, key);
1353                 rcu_read_unlock();
1354                 bpf_enable_instrumentation();
1355                 maybe_wait_bpf_programs(map);
1356                 if (err)
1357                         break;
1358         }
1359         if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1360                 err = -EFAULT;
1361
1362         kvfree(key);
1363         return err;
1364 }
1365
1366 int generic_map_update_batch(struct bpf_map *map,
1367                              const union bpf_attr *attr,
1368                              union bpf_attr __user *uattr)
1369 {
1370         void __user *values = u64_to_user_ptr(attr->batch.values);
1371         void __user *keys = u64_to_user_ptr(attr->batch.keys);
1372         u32 value_size, cp, max_count;
1373         int ufd = attr->batch.map_fd;
1374         void *key, *value;
1375         struct fd f;
1376         int err = 0;
1377
1378         if (attr->batch.elem_flags & ~BPF_F_LOCK)
1379                 return -EINVAL;
1380
1381         if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1382             !map_value_has_spin_lock(map)) {
1383                 return -EINVAL;
1384         }
1385
1386         value_size = bpf_map_value_size(map);
1387
1388         max_count = attr->batch.count;
1389         if (!max_count)
1390                 return 0;
1391
1392         key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1393         if (!key)
1394                 return -ENOMEM;
1395
1396         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1397         if (!value) {
1398                 kvfree(key);
1399                 return -ENOMEM;
1400         }
1401
1402         f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1403         for (cp = 0; cp < max_count; cp++) {
1404                 err = -EFAULT;
1405                 if (copy_from_user(key, keys + cp * map->key_size,
1406                     map->key_size) ||
1407                     copy_from_user(value, values + cp * value_size, value_size))
1408                         break;
1409
1410                 err = bpf_map_update_value(map, f, key, value,
1411                                            attr->batch.elem_flags);
1412
1413                 if (err)
1414                         break;
1415         }
1416
1417         if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1418                 err = -EFAULT;
1419
1420         kvfree(value);
1421         kvfree(key);
1422         fdput(f);
1423         return err;
1424 }
1425
1426 #define MAP_LOOKUP_RETRIES 3
1427
1428 int generic_map_lookup_batch(struct bpf_map *map,
1429                                     const union bpf_attr *attr,
1430                                     union bpf_attr __user *uattr)
1431 {
1432         void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1433         void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1434         void __user *values = u64_to_user_ptr(attr->batch.values);
1435         void __user *keys = u64_to_user_ptr(attr->batch.keys);
1436         void *buf, *buf_prevkey, *prev_key, *key, *value;
1437         int err, retry = MAP_LOOKUP_RETRIES;
1438         u32 value_size, cp, max_count;
1439
1440         if (attr->batch.elem_flags & ~BPF_F_LOCK)
1441                 return -EINVAL;
1442
1443         if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1444             !map_value_has_spin_lock(map))
1445                 return -EINVAL;
1446
1447         value_size = bpf_map_value_size(map);
1448
1449         max_count = attr->batch.count;
1450         if (!max_count)
1451                 return 0;
1452
1453         if (put_user(0, &uattr->batch.count))
1454                 return -EFAULT;
1455
1456         buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1457         if (!buf_prevkey)
1458                 return -ENOMEM;
1459
1460         buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1461         if (!buf) {
1462                 kvfree(buf_prevkey);
1463                 return -ENOMEM;
1464         }
1465
1466         err = -EFAULT;
1467         prev_key = NULL;
1468         if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1469                 goto free_buf;
1470         key = buf;
1471         value = key + map->key_size;
1472         if (ubatch)
1473                 prev_key = buf_prevkey;
1474
1475         for (cp = 0; cp < max_count;) {
1476                 rcu_read_lock();
1477                 err = map->ops->map_get_next_key(map, prev_key, key);
1478                 rcu_read_unlock();
1479                 if (err)
1480                         break;
1481                 err = bpf_map_copy_value(map, key, value,
1482                                          attr->batch.elem_flags);
1483
1484                 if (err == -ENOENT) {
1485                         if (retry) {
1486                                 retry--;
1487                                 continue;
1488                         }
1489                         err = -EINTR;
1490                         break;
1491                 }
1492
1493                 if (err)
1494                         goto free_buf;
1495
1496                 if (copy_to_user(keys + cp * map->key_size, key,
1497                                  map->key_size)) {
1498                         err = -EFAULT;
1499                         goto free_buf;
1500                 }
1501                 if (copy_to_user(values + cp * value_size, value, value_size)) {
1502                         err = -EFAULT;
1503                         goto free_buf;
1504                 }
1505
1506                 if (!prev_key)
1507                         prev_key = buf_prevkey;
1508
1509                 swap(prev_key, key);
1510                 retry = MAP_LOOKUP_RETRIES;
1511                 cp++;
1512         }
1513
1514         if (err == -EFAULT)
1515                 goto free_buf;
1516
1517         if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1518                     (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1519                 err = -EFAULT;
1520
1521 free_buf:
1522         kvfree(buf_prevkey);
1523         kvfree(buf);
1524         return err;
1525 }
1526
1527 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1528
1529 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1530 {
1531         void __user *ukey = u64_to_user_ptr(attr->key);
1532         void __user *uvalue = u64_to_user_ptr(attr->value);
1533         int ufd = attr->map_fd;
1534         struct bpf_map *map;
1535         void *key, *value;
1536         u32 value_size;
1537         struct fd f;
1538         int err;
1539
1540         if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1541                 return -EINVAL;
1542
1543         if (attr->flags & ~BPF_F_LOCK)
1544                 return -EINVAL;
1545
1546         f = fdget(ufd);
1547         map = __bpf_map_get(f);
1548         if (IS_ERR(map))
1549                 return PTR_ERR(map);
1550         bpf_map_write_active_inc(map);
1551         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1552             !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1553                 err = -EPERM;
1554                 goto err_put;
1555         }
1556
1557         if (attr->flags &&
1558             (map->map_type == BPF_MAP_TYPE_QUEUE ||
1559              map->map_type == BPF_MAP_TYPE_STACK)) {
1560                 err = -EINVAL;
1561                 goto err_put;
1562         }
1563
1564         if ((attr->flags & BPF_F_LOCK) &&
1565             !map_value_has_spin_lock(map)) {
1566                 err = -EINVAL;
1567                 goto err_put;
1568         }
1569
1570         key = __bpf_copy_key(ukey, map->key_size);
1571         if (IS_ERR(key)) {
1572                 err = PTR_ERR(key);
1573                 goto err_put;
1574         }
1575
1576         value_size = bpf_map_value_size(map);
1577
1578         err = -ENOMEM;
1579         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1580         if (!value)
1581                 goto free_key;
1582
1583         err = -ENOTSUPP;
1584         if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1585             map->map_type == BPF_MAP_TYPE_STACK) {
1586                 err = map->ops->map_pop_elem(map, value);
1587         } else if (map->map_type == BPF_MAP_TYPE_HASH ||
1588                    map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1589                    map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1590                    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1591                 if (!bpf_map_is_dev_bound(map)) {
1592                         bpf_disable_instrumentation();
1593                         rcu_read_lock();
1594                         err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1595                         rcu_read_unlock();
1596                         bpf_enable_instrumentation();
1597                 }
1598         }
1599
1600         if (err)
1601                 goto free_value;
1602
1603         if (copy_to_user(uvalue, value, value_size) != 0) {
1604                 err = -EFAULT;
1605                 goto free_value;
1606         }
1607
1608         err = 0;
1609
1610 free_value:
1611         kvfree(value);
1612 free_key:
1613         kvfree(key);
1614 err_put:
1615         bpf_map_write_active_dec(map);
1616         fdput(f);
1617         return err;
1618 }
1619
1620 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1621
1622 static int map_freeze(const union bpf_attr *attr)
1623 {
1624         int err = 0, ufd = attr->map_fd;
1625         struct bpf_map *map;
1626         struct fd f;
1627
1628         if (CHECK_ATTR(BPF_MAP_FREEZE))
1629                 return -EINVAL;
1630
1631         f = fdget(ufd);
1632         map = __bpf_map_get(f);
1633         if (IS_ERR(map))
1634                 return PTR_ERR(map);
1635
1636         if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1637             map_value_has_timer(map)) {
1638                 fdput(f);
1639                 return -ENOTSUPP;
1640         }
1641
1642         mutex_lock(&map->freeze_mutex);
1643         if (bpf_map_write_active(map)) {
1644                 err = -EBUSY;
1645                 goto err_put;
1646         }
1647         if (READ_ONCE(map->frozen)) {
1648                 err = -EBUSY;
1649                 goto err_put;
1650         }
1651         if (!bpf_capable()) {
1652                 err = -EPERM;
1653                 goto err_put;
1654         }
1655
1656         WRITE_ONCE(map->frozen, true);
1657 err_put:
1658         mutex_unlock(&map->freeze_mutex);
1659         fdput(f);
1660         return err;
1661 }
1662
1663 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1664 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1665         [_id] = & _name ## _prog_ops,
1666 #define BPF_MAP_TYPE(_id, _ops)
1667 #define BPF_LINK_TYPE(_id, _name)
1668 #include <linux/bpf_types.h>
1669 #undef BPF_PROG_TYPE
1670 #undef BPF_MAP_TYPE
1671 #undef BPF_LINK_TYPE
1672 };
1673
1674 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1675 {
1676         const struct bpf_prog_ops *ops;
1677
1678         if (type >= ARRAY_SIZE(bpf_prog_types))
1679                 return -EINVAL;
1680         type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1681         ops = bpf_prog_types[type];
1682         if (!ops)
1683                 return -EINVAL;
1684
1685         if (!bpf_prog_is_dev_bound(prog->aux))
1686                 prog->aux->ops = ops;
1687         else
1688                 prog->aux->ops = &bpf_offload_prog_ops;
1689         prog->type = type;
1690         return 0;
1691 }
1692
1693 enum bpf_audit {
1694         BPF_AUDIT_LOAD,
1695         BPF_AUDIT_UNLOAD,
1696         BPF_AUDIT_MAX,
1697 };
1698
1699 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1700         [BPF_AUDIT_LOAD]   = "LOAD",
1701         [BPF_AUDIT_UNLOAD] = "UNLOAD",
1702 };
1703
1704 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1705 {
1706         struct audit_context *ctx = NULL;
1707         struct audit_buffer *ab;
1708
1709         if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1710                 return;
1711         if (audit_enabled == AUDIT_OFF)
1712                 return;
1713         if (op == BPF_AUDIT_LOAD)
1714                 ctx = audit_context();
1715         ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1716         if (unlikely(!ab))
1717                 return;
1718         audit_log_format(ab, "prog-id=%u op=%s",
1719                          prog->aux->id, bpf_audit_str[op]);
1720         audit_log_end(ab);
1721 }
1722
1723 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1724 {
1725         int id;
1726
1727         idr_preload(GFP_KERNEL);
1728         spin_lock_bh(&prog_idr_lock);
1729         id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1730         if (id > 0)
1731                 prog->aux->id = id;
1732         spin_unlock_bh(&prog_idr_lock);
1733         idr_preload_end();
1734
1735         /* id is in [1, INT_MAX) */
1736         if (WARN_ON_ONCE(!id))
1737                 return -ENOSPC;
1738
1739         return id > 0 ? 0 : id;
1740 }
1741
1742 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1743 {
1744         unsigned long flags;
1745
1746         /* cBPF to eBPF migrations are currently not in the idr store.
1747          * Offloaded programs are removed from the store when their device
1748          * disappears - even if someone grabs an fd to them they are unusable,
1749          * simply waiting for refcnt to drop to be freed.
1750          */
1751         if (!prog->aux->id)
1752                 return;
1753
1754         if (do_idr_lock)
1755                 spin_lock_irqsave(&prog_idr_lock, flags);
1756         else
1757                 __acquire(&prog_idr_lock);
1758
1759         idr_remove(&prog_idr, prog->aux->id);
1760         prog->aux->id = 0;
1761
1762         if (do_idr_lock)
1763                 spin_unlock_irqrestore(&prog_idr_lock, flags);
1764         else
1765                 __release(&prog_idr_lock);
1766 }
1767
1768 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1769 {
1770         struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1771
1772         kvfree(aux->func_info);
1773         kfree(aux->func_info_aux);
1774         free_uid(aux->user);
1775         security_bpf_prog_free(aux);
1776         bpf_prog_free(aux->prog);
1777 }
1778
1779 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1780 {
1781         bpf_prog_kallsyms_del_all(prog);
1782         btf_put(prog->aux->btf);
1783         kvfree(prog->aux->jited_linfo);
1784         kvfree(prog->aux->linfo);
1785         kfree(prog->aux->kfunc_tab);
1786         if (prog->aux->attach_btf)
1787                 btf_put(prog->aux->attach_btf);
1788
1789         if (deferred) {
1790                 if (prog->aux->sleepable)
1791                         call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1792                 else
1793                         call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1794         } else {
1795                 __bpf_prog_put_rcu(&prog->aux->rcu);
1796         }
1797 }
1798
1799 static void bpf_prog_put_deferred(struct work_struct *work)
1800 {
1801         struct bpf_prog_aux *aux;
1802         struct bpf_prog *prog;
1803
1804         aux = container_of(work, struct bpf_prog_aux, work);
1805         prog = aux->prog;
1806         perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1807         bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1808         __bpf_prog_put_noref(prog, true);
1809 }
1810
1811 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1812 {
1813         struct bpf_prog_aux *aux = prog->aux;
1814
1815         if (atomic64_dec_and_test(&aux->refcnt)) {
1816                 /* bpf_prog_free_id() must be called first */
1817                 bpf_prog_free_id(prog, do_idr_lock);
1818
1819                 if (in_irq() || irqs_disabled()) {
1820                         INIT_WORK(&aux->work, bpf_prog_put_deferred);
1821                         schedule_work(&aux->work);
1822                 } else {
1823                         bpf_prog_put_deferred(&aux->work);
1824                 }
1825         }
1826 }
1827
1828 void bpf_prog_put(struct bpf_prog *prog)
1829 {
1830         __bpf_prog_put(prog, true);
1831 }
1832 EXPORT_SYMBOL_GPL(bpf_prog_put);
1833
1834 static int bpf_prog_release(struct inode *inode, struct file *filp)
1835 {
1836         struct bpf_prog *prog = filp->private_data;
1837
1838         bpf_prog_put(prog);
1839         return 0;
1840 }
1841
1842 struct bpf_prog_kstats {
1843         u64 nsecs;
1844         u64 cnt;
1845         u64 misses;
1846 };
1847
1848 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1849                                struct bpf_prog_kstats *stats)
1850 {
1851         u64 nsecs = 0, cnt = 0, misses = 0;
1852         int cpu;
1853
1854         for_each_possible_cpu(cpu) {
1855                 const struct bpf_prog_stats *st;
1856                 unsigned int start;
1857                 u64 tnsecs, tcnt, tmisses;
1858
1859                 st = per_cpu_ptr(prog->stats, cpu);
1860                 do {
1861                         start = u64_stats_fetch_begin_irq(&st->syncp);
1862                         tnsecs = u64_stats_read(&st->nsecs);
1863                         tcnt = u64_stats_read(&st->cnt);
1864                         tmisses = u64_stats_read(&st->misses);
1865                 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1866                 nsecs += tnsecs;
1867                 cnt += tcnt;
1868                 misses += tmisses;
1869         }
1870         stats->nsecs = nsecs;
1871         stats->cnt = cnt;
1872         stats->misses = misses;
1873 }
1874
1875 #ifdef CONFIG_PROC_FS
1876 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1877 {
1878         const struct bpf_prog *prog = filp->private_data;
1879         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1880         struct bpf_prog_kstats stats;
1881
1882         bpf_prog_get_stats(prog, &stats);
1883         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1884         seq_printf(m,
1885                    "prog_type:\t%u\n"
1886                    "prog_jited:\t%u\n"
1887                    "prog_tag:\t%s\n"
1888                    "memlock:\t%llu\n"
1889                    "prog_id:\t%u\n"
1890                    "run_time_ns:\t%llu\n"
1891                    "run_cnt:\t%llu\n"
1892                    "recursion_misses:\t%llu\n"
1893                    "verified_insns:\t%u\n",
1894                    prog->type,
1895                    prog->jited,
1896                    prog_tag,
1897                    prog->pages * 1ULL << PAGE_SHIFT,
1898                    prog->aux->id,
1899                    stats.nsecs,
1900                    stats.cnt,
1901                    stats.misses,
1902                    prog->aux->verified_insns);
1903 }
1904 #endif
1905
1906 const struct file_operations bpf_prog_fops = {
1907 #ifdef CONFIG_PROC_FS
1908         .show_fdinfo    = bpf_prog_show_fdinfo,
1909 #endif
1910         .release        = bpf_prog_release,
1911         .read           = bpf_dummy_read,
1912         .write          = bpf_dummy_write,
1913 };
1914
1915 int bpf_prog_new_fd(struct bpf_prog *prog)
1916 {
1917         int ret;
1918
1919         ret = security_bpf_prog(prog);
1920         if (ret < 0)
1921                 return ret;
1922
1923         return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1924                                 O_RDWR | O_CLOEXEC);
1925 }
1926
1927 static struct bpf_prog *____bpf_prog_get(struct fd f)
1928 {
1929         if (!f.file)
1930                 return ERR_PTR(-EBADF);
1931         if (f.file->f_op != &bpf_prog_fops) {
1932                 fdput(f);
1933                 return ERR_PTR(-EINVAL);
1934         }
1935
1936         return f.file->private_data;
1937 }
1938
1939 void bpf_prog_add(struct bpf_prog *prog, int i)
1940 {
1941         atomic64_add(i, &prog->aux->refcnt);
1942 }
1943 EXPORT_SYMBOL_GPL(bpf_prog_add);
1944
1945 void bpf_prog_sub(struct bpf_prog *prog, int i)
1946 {
1947         /* Only to be used for undoing previous bpf_prog_add() in some
1948          * error path. We still know that another entity in our call
1949          * path holds a reference to the program, thus atomic_sub() can
1950          * be safely used in such cases!
1951          */
1952         WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1953 }
1954 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1955
1956 void bpf_prog_inc(struct bpf_prog *prog)
1957 {
1958         atomic64_inc(&prog->aux->refcnt);
1959 }
1960 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1961
1962 /* prog_idr_lock should have been held */
1963 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1964 {
1965         int refold;
1966
1967         refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1968
1969         if (!refold)
1970                 return ERR_PTR(-ENOENT);
1971
1972         return prog;
1973 }
1974 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1975
1976 bool bpf_prog_get_ok(struct bpf_prog *prog,
1977                             enum bpf_prog_type *attach_type, bool attach_drv)
1978 {
1979         /* not an attachment, just a refcount inc, always allow */
1980         if (!attach_type)
1981                 return true;
1982
1983         if (prog->type != *attach_type)
1984                 return false;
1985         if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1986                 return false;
1987
1988         return true;
1989 }
1990
1991 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1992                                        bool attach_drv)
1993 {
1994         struct fd f = fdget(ufd);
1995         struct bpf_prog *prog;
1996
1997         prog = ____bpf_prog_get(f);
1998         if (IS_ERR(prog))
1999                 return prog;
2000         if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
2001                 prog = ERR_PTR(-EINVAL);
2002                 goto out;
2003         }
2004
2005         bpf_prog_inc(prog);
2006 out:
2007         fdput(f);
2008         return prog;
2009 }
2010
2011 struct bpf_prog *bpf_prog_get(u32 ufd)
2012 {
2013         return __bpf_prog_get(ufd, NULL, false);
2014 }
2015
2016 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2017                                        bool attach_drv)
2018 {
2019         return __bpf_prog_get(ufd, &type, attach_drv);
2020 }
2021 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2022
2023 /* Initially all BPF programs could be loaded w/o specifying
2024  * expected_attach_type. Later for some of them specifying expected_attach_type
2025  * at load time became required so that program could be validated properly.
2026  * Programs of types that are allowed to be loaded both w/ and w/o (for
2027  * backward compatibility) expected_attach_type, should have the default attach
2028  * type assigned to expected_attach_type for the latter case, so that it can be
2029  * validated later at attach time.
2030  *
2031  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2032  * prog type requires it but has some attach types that have to be backward
2033  * compatible.
2034  */
2035 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2036 {
2037         switch (attr->prog_type) {
2038         case BPF_PROG_TYPE_CGROUP_SOCK:
2039                 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2040                  * exist so checking for non-zero is the way to go here.
2041                  */
2042                 if (!attr->expected_attach_type)
2043                         attr->expected_attach_type =
2044                                 BPF_CGROUP_INET_SOCK_CREATE;
2045                 break;
2046         case BPF_PROG_TYPE_SK_REUSEPORT:
2047                 if (!attr->expected_attach_type)
2048                         attr->expected_attach_type =
2049                                 BPF_SK_REUSEPORT_SELECT;
2050                 break;
2051         }
2052 }
2053
2054 static int
2055 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2056                            enum bpf_attach_type expected_attach_type,
2057                            struct btf *attach_btf, u32 btf_id,
2058                            struct bpf_prog *dst_prog)
2059 {
2060         if (btf_id) {
2061                 if (btf_id > BTF_MAX_TYPE)
2062                         return -EINVAL;
2063
2064                 if (!attach_btf && !dst_prog)
2065                         return -EINVAL;
2066
2067                 switch (prog_type) {
2068                 case BPF_PROG_TYPE_TRACING:
2069                 case BPF_PROG_TYPE_LSM:
2070                 case BPF_PROG_TYPE_STRUCT_OPS:
2071                 case BPF_PROG_TYPE_EXT:
2072                         break;
2073                 default:
2074                         return -EINVAL;
2075                 }
2076         }
2077
2078         if (attach_btf && (!btf_id || dst_prog))
2079                 return -EINVAL;
2080
2081         if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2082             prog_type != BPF_PROG_TYPE_EXT)
2083                 return -EINVAL;
2084
2085         switch (prog_type) {
2086         case BPF_PROG_TYPE_CGROUP_SOCK:
2087                 switch (expected_attach_type) {
2088                 case BPF_CGROUP_INET_SOCK_CREATE:
2089                 case BPF_CGROUP_INET_SOCK_RELEASE:
2090                 case BPF_CGROUP_INET4_POST_BIND:
2091                 case BPF_CGROUP_INET6_POST_BIND:
2092                         return 0;
2093                 default:
2094                         return -EINVAL;
2095                 }
2096         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2097                 switch (expected_attach_type) {
2098                 case BPF_CGROUP_INET4_BIND:
2099                 case BPF_CGROUP_INET6_BIND:
2100                 case BPF_CGROUP_INET4_CONNECT:
2101                 case BPF_CGROUP_INET6_CONNECT:
2102                 case BPF_CGROUP_INET4_GETPEERNAME:
2103                 case BPF_CGROUP_INET6_GETPEERNAME:
2104                 case BPF_CGROUP_INET4_GETSOCKNAME:
2105                 case BPF_CGROUP_INET6_GETSOCKNAME:
2106                 case BPF_CGROUP_UDP4_SENDMSG:
2107                 case BPF_CGROUP_UDP6_SENDMSG:
2108                 case BPF_CGROUP_UDP4_RECVMSG:
2109                 case BPF_CGROUP_UDP6_RECVMSG:
2110                         return 0;
2111                 default:
2112                         return -EINVAL;
2113                 }
2114         case BPF_PROG_TYPE_CGROUP_SKB:
2115                 switch (expected_attach_type) {
2116                 case BPF_CGROUP_INET_INGRESS:
2117                 case BPF_CGROUP_INET_EGRESS:
2118                         return 0;
2119                 default:
2120                         return -EINVAL;
2121                 }
2122         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2123                 switch (expected_attach_type) {
2124                 case BPF_CGROUP_SETSOCKOPT:
2125                 case BPF_CGROUP_GETSOCKOPT:
2126                         return 0;
2127                 default:
2128                         return -EINVAL;
2129                 }
2130         case BPF_PROG_TYPE_SK_LOOKUP:
2131                 if (expected_attach_type == BPF_SK_LOOKUP)
2132                         return 0;
2133                 return -EINVAL;
2134         case BPF_PROG_TYPE_SK_REUSEPORT:
2135                 switch (expected_attach_type) {
2136                 case BPF_SK_REUSEPORT_SELECT:
2137                 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2138                         return 0;
2139                 default:
2140                         return -EINVAL;
2141                 }
2142         case BPF_PROG_TYPE_SYSCALL:
2143         case BPF_PROG_TYPE_EXT:
2144                 if (expected_attach_type)
2145                         return -EINVAL;
2146                 fallthrough;
2147         default:
2148                 return 0;
2149         }
2150 }
2151
2152 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2153 {
2154         switch (prog_type) {
2155         case BPF_PROG_TYPE_SCHED_CLS:
2156         case BPF_PROG_TYPE_SCHED_ACT:
2157         case BPF_PROG_TYPE_XDP:
2158         case BPF_PROG_TYPE_LWT_IN:
2159         case BPF_PROG_TYPE_LWT_OUT:
2160         case BPF_PROG_TYPE_LWT_XMIT:
2161         case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2162         case BPF_PROG_TYPE_SK_SKB:
2163         case BPF_PROG_TYPE_SK_MSG:
2164         case BPF_PROG_TYPE_LIRC_MODE2:
2165         case BPF_PROG_TYPE_FLOW_DISSECTOR:
2166         case BPF_PROG_TYPE_CGROUP_DEVICE:
2167         case BPF_PROG_TYPE_CGROUP_SOCK:
2168         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2169         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2170         case BPF_PROG_TYPE_CGROUP_SYSCTL:
2171         case BPF_PROG_TYPE_SOCK_OPS:
2172         case BPF_PROG_TYPE_EXT: /* extends any prog */
2173                 return true;
2174         case BPF_PROG_TYPE_CGROUP_SKB:
2175                 /* always unpriv */
2176         case BPF_PROG_TYPE_SK_REUSEPORT:
2177                 /* equivalent to SOCKET_FILTER. need CAP_BPF only */
2178         default:
2179                 return false;
2180         }
2181 }
2182
2183 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2184 {
2185         switch (prog_type) {
2186         case BPF_PROG_TYPE_KPROBE:
2187         case BPF_PROG_TYPE_TRACEPOINT:
2188         case BPF_PROG_TYPE_PERF_EVENT:
2189         case BPF_PROG_TYPE_RAW_TRACEPOINT:
2190         case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2191         case BPF_PROG_TYPE_TRACING:
2192         case BPF_PROG_TYPE_LSM:
2193         case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2194         case BPF_PROG_TYPE_EXT: /* extends any prog */
2195                 return true;
2196         default:
2197                 return false;
2198         }
2199 }
2200
2201 /* last field in 'union bpf_attr' used by this command */
2202 #define BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
2203
2204 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2205 {
2206         enum bpf_prog_type type = attr->prog_type;
2207         struct bpf_prog *prog, *dst_prog = NULL;
2208         struct btf *attach_btf = NULL;
2209         int err;
2210         char license[128];
2211         bool is_gpl;
2212
2213         if (CHECK_ATTR(BPF_PROG_LOAD))
2214                 return -EINVAL;
2215
2216         if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2217                                  BPF_F_ANY_ALIGNMENT |
2218                                  BPF_F_TEST_STATE_FREQ |
2219                                  BPF_F_SLEEPABLE |
2220                                  BPF_F_TEST_RND_HI32))
2221                 return -EINVAL;
2222
2223         if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2224             (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2225             !bpf_capable())
2226                 return -EPERM;
2227
2228         /* copy eBPF program license from user space */
2229         if (strncpy_from_bpfptr(license,
2230                                 make_bpfptr(attr->license, uattr.is_kernel),
2231                                 sizeof(license) - 1) < 0)
2232                 return -EFAULT;
2233         license[sizeof(license) - 1] = 0;
2234
2235         /* eBPF programs must be GPL compatible to use GPL-ed functions */
2236         is_gpl = license_is_gpl_compatible(license);
2237
2238         if (attr->insn_cnt == 0 ||
2239             attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2240                 return -E2BIG;
2241         if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2242             type != BPF_PROG_TYPE_CGROUP_SKB &&
2243             !bpf_capable())
2244                 return -EPERM;
2245
2246         if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2247                 return -EPERM;
2248         if (is_perfmon_prog_type(type) && !perfmon_capable())
2249                 return -EPERM;
2250
2251         /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2252          * or btf, we need to check which one it is
2253          */
2254         if (attr->attach_prog_fd) {
2255                 dst_prog = bpf_prog_get(attr->attach_prog_fd);
2256                 if (IS_ERR(dst_prog)) {
2257                         dst_prog = NULL;
2258                         attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2259                         if (IS_ERR(attach_btf))
2260                                 return -EINVAL;
2261                         if (!btf_is_kernel(attach_btf)) {
2262                                 /* attaching through specifying bpf_prog's BTF
2263                                  * objects directly might be supported eventually
2264                                  */
2265                                 btf_put(attach_btf);
2266                                 return -ENOTSUPP;
2267                         }
2268                 }
2269         } else if (attr->attach_btf_id) {
2270                 /* fall back to vmlinux BTF, if BTF type ID is specified */
2271                 attach_btf = bpf_get_btf_vmlinux();
2272                 if (IS_ERR(attach_btf))
2273                         return PTR_ERR(attach_btf);
2274                 if (!attach_btf)
2275                         return -EINVAL;
2276                 btf_get(attach_btf);
2277         }
2278
2279         bpf_prog_load_fixup_attach_type(attr);
2280         if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2281                                        attach_btf, attr->attach_btf_id,
2282                                        dst_prog)) {
2283                 if (dst_prog)
2284                         bpf_prog_put(dst_prog);
2285                 if (attach_btf)
2286                         btf_put(attach_btf);
2287                 return -EINVAL;
2288         }
2289
2290         /* plain bpf_prog allocation */
2291         prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2292         if (!prog) {
2293                 if (dst_prog)
2294                         bpf_prog_put(dst_prog);
2295                 if (attach_btf)
2296                         btf_put(attach_btf);
2297                 return -ENOMEM;
2298         }
2299
2300         prog->expected_attach_type = attr->expected_attach_type;
2301         prog->aux->attach_btf = attach_btf;
2302         prog->aux->attach_btf_id = attr->attach_btf_id;
2303         prog->aux->dst_prog = dst_prog;
2304         prog->aux->offload_requested = !!attr->prog_ifindex;
2305         prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2306
2307         err = security_bpf_prog_alloc(prog->aux);
2308         if (err)
2309                 goto free_prog;
2310
2311         prog->aux->user = get_current_user();
2312         prog->len = attr->insn_cnt;
2313
2314         err = -EFAULT;
2315         if (copy_from_bpfptr(prog->insns,
2316                              make_bpfptr(attr->insns, uattr.is_kernel),
2317                              bpf_prog_insn_size(prog)) != 0)
2318                 goto free_prog_sec;
2319
2320         prog->orig_prog = NULL;
2321         prog->jited = 0;
2322
2323         atomic64_set(&prog->aux->refcnt, 1);
2324         prog->gpl_compatible = is_gpl ? 1 : 0;
2325
2326         if (bpf_prog_is_dev_bound(prog->aux)) {
2327                 err = bpf_prog_offload_init(prog, attr);
2328                 if (err)
2329                         goto free_prog_sec;
2330         }
2331
2332         /* find program type: socket_filter vs tracing_filter */
2333         err = find_prog_type(type, prog);
2334         if (err < 0)
2335                 goto free_prog_sec;
2336
2337         prog->aux->load_time = ktime_get_boottime_ns();
2338         err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2339                                sizeof(attr->prog_name));
2340         if (err < 0)
2341                 goto free_prog_sec;
2342
2343         /* run eBPF verifier */
2344         err = bpf_check(&prog, attr, uattr);
2345         if (err < 0)
2346                 goto free_used_maps;
2347
2348         prog = bpf_prog_select_runtime(prog, &err);
2349         if (err < 0)
2350                 goto free_used_maps;
2351
2352         err = bpf_prog_alloc_id(prog);
2353         if (err)
2354                 goto free_used_maps;
2355
2356         /* Upon success of bpf_prog_alloc_id(), the BPF prog is
2357          * effectively publicly exposed. However, retrieving via
2358          * bpf_prog_get_fd_by_id() will take another reference,
2359          * therefore it cannot be gone underneath us.
2360          *
2361          * Only for the time /after/ successful bpf_prog_new_fd()
2362          * and before returning to userspace, we might just hold
2363          * one reference and any parallel close on that fd could
2364          * rip everything out. Hence, below notifications must
2365          * happen before bpf_prog_new_fd().
2366          *
2367          * Also, any failure handling from this point onwards must
2368          * be using bpf_prog_put() given the program is exposed.
2369          */
2370         bpf_prog_kallsyms_add(prog);
2371         perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2372         bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2373
2374         err = bpf_prog_new_fd(prog);
2375         if (err < 0)
2376                 bpf_prog_put(prog);
2377         return err;
2378
2379 free_used_maps:
2380         /* In case we have subprogs, we need to wait for a grace
2381          * period before we can tear down JIT memory since symbols
2382          * are already exposed under kallsyms.
2383          */
2384         __bpf_prog_put_noref(prog, prog->aux->func_cnt);
2385         return err;
2386 free_prog_sec:
2387         free_uid(prog->aux->user);
2388         security_bpf_prog_free(prog->aux);
2389 free_prog:
2390         if (prog->aux->attach_btf)
2391                 btf_put(prog->aux->attach_btf);
2392         bpf_prog_free(prog);
2393         return err;
2394 }
2395
2396 #define BPF_OBJ_LAST_FIELD file_flags
2397
2398 static int bpf_obj_pin(const union bpf_attr *attr)
2399 {
2400         if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2401                 return -EINVAL;
2402
2403         return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2404 }
2405
2406 static int bpf_obj_get(const union bpf_attr *attr)
2407 {
2408         if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2409             attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2410                 return -EINVAL;
2411
2412         return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2413                                 attr->file_flags);
2414 }
2415
2416 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2417                    const struct bpf_link_ops *ops, struct bpf_prog *prog)
2418 {
2419         atomic64_set(&link->refcnt, 1);
2420         link->type = type;
2421         link->id = 0;
2422         link->ops = ops;
2423         link->prog = prog;
2424 }
2425
2426 static void bpf_link_free_id(int id)
2427 {
2428         if (!id)
2429                 return;
2430
2431         spin_lock_bh(&link_idr_lock);
2432         idr_remove(&link_idr, id);
2433         spin_unlock_bh(&link_idr_lock);
2434 }
2435
2436 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2437  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2438  * anon_inode's release() call. This helper marksbpf_link as
2439  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2440  * is not decremented, it's the responsibility of a calling code that failed
2441  * to complete bpf_link initialization.
2442  */
2443 void bpf_link_cleanup(struct bpf_link_primer *primer)
2444 {
2445         primer->link->prog = NULL;
2446         bpf_link_free_id(primer->id);
2447         fput(primer->file);
2448         put_unused_fd(primer->fd);
2449 }
2450
2451 void bpf_link_inc(struct bpf_link *link)
2452 {
2453         atomic64_inc(&link->refcnt);
2454 }
2455
2456 /* bpf_link_free is guaranteed to be called from process context */
2457 static void bpf_link_free(struct bpf_link *link)
2458 {
2459         bpf_link_free_id(link->id);
2460         if (link->prog) {
2461                 /* detach BPF program, clean up used resources */
2462                 link->ops->release(link);
2463                 bpf_prog_put(link->prog);
2464         }
2465         /* free bpf_link and its containing memory */
2466         link->ops->dealloc(link);
2467 }
2468
2469 static void bpf_link_put_deferred(struct work_struct *work)
2470 {
2471         struct bpf_link *link = container_of(work, struct bpf_link, work);
2472
2473         bpf_link_free(link);
2474 }
2475
2476 /* bpf_link_put can be called from atomic context, but ensures that resources
2477  * are freed from process context
2478  */
2479 void bpf_link_put(struct bpf_link *link)
2480 {
2481         if (!atomic64_dec_and_test(&link->refcnt))
2482                 return;
2483
2484         if (in_atomic()) {
2485                 INIT_WORK(&link->work, bpf_link_put_deferred);
2486                 schedule_work(&link->work);
2487         } else {
2488                 bpf_link_free(link);
2489         }
2490 }
2491
2492 static int bpf_link_release(struct inode *inode, struct file *filp)
2493 {
2494         struct bpf_link *link = filp->private_data;
2495
2496         bpf_link_put(link);
2497         return 0;
2498 }
2499
2500 #ifdef CONFIG_PROC_FS
2501 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2502 #define BPF_MAP_TYPE(_id, _ops)
2503 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2504 static const char *bpf_link_type_strs[] = {
2505         [BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2506 #include <linux/bpf_types.h>
2507 };
2508 #undef BPF_PROG_TYPE
2509 #undef BPF_MAP_TYPE
2510 #undef BPF_LINK_TYPE
2511
2512 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2513 {
2514         const struct bpf_link *link = filp->private_data;
2515         const struct bpf_prog *prog = link->prog;
2516         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2517
2518         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2519         seq_printf(m,
2520                    "link_type:\t%s\n"
2521                    "link_id:\t%u\n"
2522                    "prog_tag:\t%s\n"
2523                    "prog_id:\t%u\n",
2524                    bpf_link_type_strs[link->type],
2525                    link->id,
2526                    prog_tag,
2527                    prog->aux->id);
2528         if (link->ops->show_fdinfo)
2529                 link->ops->show_fdinfo(link, m);
2530 }
2531 #endif
2532
2533 static const struct file_operations bpf_link_fops = {
2534 #ifdef CONFIG_PROC_FS
2535         .show_fdinfo    = bpf_link_show_fdinfo,
2536 #endif
2537         .release        = bpf_link_release,
2538         .read           = bpf_dummy_read,
2539         .write          = bpf_dummy_write,
2540 };
2541
2542 static int bpf_link_alloc_id(struct bpf_link *link)
2543 {
2544         int id;
2545
2546         idr_preload(GFP_KERNEL);
2547         spin_lock_bh(&link_idr_lock);
2548         id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2549         spin_unlock_bh(&link_idr_lock);
2550         idr_preload_end();
2551
2552         return id;
2553 }
2554
2555 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2556  * reserving unused FD and allocating ID from link_idr. This is to be paired
2557  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2558  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2559  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2560  * transient state is passed around in struct bpf_link_primer.
2561  * This is preferred way to create and initialize bpf_link, especially when
2562  * there are complicated and expensive operations inbetween creating bpf_link
2563  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2564  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2565  * expensive (and potentially failing) roll back operations in a rare case
2566  * that file, FD, or ID can't be allocated.
2567  */
2568 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2569 {
2570         struct file *file;
2571         int fd, id;
2572
2573         fd = get_unused_fd_flags(O_CLOEXEC);
2574         if (fd < 0)
2575                 return fd;
2576
2577
2578         id = bpf_link_alloc_id(link);
2579         if (id < 0) {
2580                 put_unused_fd(fd);
2581                 return id;
2582         }
2583
2584         file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2585         if (IS_ERR(file)) {
2586                 bpf_link_free_id(id);
2587                 put_unused_fd(fd);
2588                 return PTR_ERR(file);
2589         }
2590
2591         primer->link = link;
2592         primer->file = file;
2593         primer->fd = fd;
2594         primer->id = id;
2595         return 0;
2596 }
2597
2598 int bpf_link_settle(struct bpf_link_primer *primer)
2599 {
2600         /* make bpf_link fetchable by ID */
2601         spin_lock_bh(&link_idr_lock);
2602         primer->link->id = primer->id;
2603         spin_unlock_bh(&link_idr_lock);
2604         /* make bpf_link fetchable by FD */
2605         fd_install(primer->fd, primer->file);
2606         /* pass through installed FD */
2607         return primer->fd;
2608 }
2609
2610 int bpf_link_new_fd(struct bpf_link *link)
2611 {
2612         return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2613 }
2614
2615 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2616 {
2617         struct fd f = fdget(ufd);
2618         struct bpf_link *link;
2619
2620         if (!f.file)
2621                 return ERR_PTR(-EBADF);
2622         if (f.file->f_op != &bpf_link_fops) {
2623                 fdput(f);
2624                 return ERR_PTR(-EINVAL);
2625         }
2626
2627         link = f.file->private_data;
2628         bpf_link_inc(link);
2629         fdput(f);
2630
2631         return link;
2632 }
2633
2634 struct bpf_tracing_link {
2635         struct bpf_link link;
2636         enum bpf_attach_type attach_type;
2637         struct bpf_trampoline *trampoline;
2638         struct bpf_prog *tgt_prog;
2639 };
2640
2641 static void bpf_tracing_link_release(struct bpf_link *link)
2642 {
2643         struct bpf_tracing_link *tr_link =
2644                 container_of(link, struct bpf_tracing_link, link);
2645
2646         WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2647                                                 tr_link->trampoline));
2648
2649         bpf_trampoline_put(tr_link->trampoline);
2650
2651         /* tgt_prog is NULL if target is a kernel function */
2652         if (tr_link->tgt_prog)
2653                 bpf_prog_put(tr_link->tgt_prog);
2654 }
2655
2656 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2657 {
2658         struct bpf_tracing_link *tr_link =
2659                 container_of(link, struct bpf_tracing_link, link);
2660
2661         kfree(tr_link);
2662 }
2663
2664 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2665                                          struct seq_file *seq)
2666 {
2667         struct bpf_tracing_link *tr_link =
2668                 container_of(link, struct bpf_tracing_link, link);
2669
2670         seq_printf(seq,
2671                    "attach_type:\t%d\n",
2672                    tr_link->attach_type);
2673 }
2674
2675 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2676                                            struct bpf_link_info *info)
2677 {
2678         struct bpf_tracing_link *tr_link =
2679                 container_of(link, struct bpf_tracing_link, link);
2680
2681         info->tracing.attach_type = tr_link->attach_type;
2682         bpf_trampoline_unpack_key(tr_link->trampoline->key,
2683                                   &info->tracing.target_obj_id,
2684                                   &info->tracing.target_btf_id);
2685
2686         return 0;
2687 }
2688
2689 static const struct bpf_link_ops bpf_tracing_link_lops = {
2690         .release = bpf_tracing_link_release,
2691         .dealloc = bpf_tracing_link_dealloc,
2692         .show_fdinfo = bpf_tracing_link_show_fdinfo,
2693         .fill_link_info = bpf_tracing_link_fill_link_info,
2694 };
2695
2696 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2697                                    int tgt_prog_fd,
2698                                    u32 btf_id)
2699 {
2700         struct bpf_link_primer link_primer;
2701         struct bpf_prog *tgt_prog = NULL;
2702         struct bpf_trampoline *tr = NULL;
2703         struct bpf_tracing_link *link;
2704         u64 key = 0;
2705         int err;
2706
2707         switch (prog->type) {
2708         case BPF_PROG_TYPE_TRACING:
2709                 if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2710                     prog->expected_attach_type != BPF_TRACE_FEXIT &&
2711                     prog->expected_attach_type != BPF_MODIFY_RETURN) {
2712                         err = -EINVAL;
2713                         goto out_put_prog;
2714                 }
2715                 break;
2716         case BPF_PROG_TYPE_EXT:
2717                 if (prog->expected_attach_type != 0) {
2718                         err = -EINVAL;
2719                         goto out_put_prog;
2720                 }
2721                 break;
2722         case BPF_PROG_TYPE_LSM:
2723                 if (prog->expected_attach_type != BPF_LSM_MAC) {
2724                         err = -EINVAL;
2725                         goto out_put_prog;
2726                 }
2727                 break;
2728         default:
2729                 err = -EINVAL;
2730                 goto out_put_prog;
2731         }
2732
2733         if (!!tgt_prog_fd != !!btf_id) {
2734                 err = -EINVAL;
2735                 goto out_put_prog;
2736         }
2737
2738         if (tgt_prog_fd) {
2739                 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2740                 if (prog->type != BPF_PROG_TYPE_EXT) {
2741                         err = -EINVAL;
2742                         goto out_put_prog;
2743                 }
2744
2745                 tgt_prog = bpf_prog_get(tgt_prog_fd);
2746                 if (IS_ERR(tgt_prog)) {
2747                         err = PTR_ERR(tgt_prog);
2748                         tgt_prog = NULL;
2749                         goto out_put_prog;
2750                 }
2751
2752                 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2753         }
2754
2755         link = kzalloc(sizeof(*link), GFP_USER);
2756         if (!link) {
2757                 err = -ENOMEM;
2758                 goto out_put_prog;
2759         }
2760         bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2761                       &bpf_tracing_link_lops, prog);
2762         link->attach_type = prog->expected_attach_type;
2763
2764         mutex_lock(&prog->aux->dst_mutex);
2765
2766         /* There are a few possible cases here:
2767          *
2768          * - if prog->aux->dst_trampoline is set, the program was just loaded
2769          *   and not yet attached to anything, so we can use the values stored
2770          *   in prog->aux
2771          *
2772          * - if prog->aux->dst_trampoline is NULL, the program has already been
2773          *   attached to a target and its initial target was cleared (below)
2774          *
2775          * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2776          *   target_btf_id using the link_create API.
2777          *
2778          * - if tgt_prog == NULL when this function was called using the old
2779          *   raw_tracepoint_open API, and we need a target from prog->aux
2780          *
2781          * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2782          *   was detached and is going for re-attachment.
2783          */
2784         if (!prog->aux->dst_trampoline && !tgt_prog) {
2785                 /*
2786                  * Allow re-attach for TRACING and LSM programs. If it's
2787                  * currently linked, bpf_trampoline_link_prog will fail.
2788                  * EXT programs need to specify tgt_prog_fd, so they
2789                  * re-attach in separate code path.
2790                  */
2791                 if (prog->type != BPF_PROG_TYPE_TRACING &&
2792                     prog->type != BPF_PROG_TYPE_LSM) {
2793                         err = -EINVAL;
2794                         goto out_unlock;
2795                 }
2796                 btf_id = prog->aux->attach_btf_id;
2797                 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2798         }
2799
2800         if (!prog->aux->dst_trampoline ||
2801             (key && key != prog->aux->dst_trampoline->key)) {
2802                 /* If there is no saved target, or the specified target is
2803                  * different from the destination specified at load time, we
2804                  * need a new trampoline and a check for compatibility
2805                  */
2806                 struct bpf_attach_target_info tgt_info = {};
2807
2808                 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2809                                               &tgt_info);
2810                 if (err)
2811                         goto out_unlock;
2812
2813                 tr = bpf_trampoline_get(key, &tgt_info);
2814                 if (!tr) {
2815                         err = -ENOMEM;
2816                         goto out_unlock;
2817                 }
2818         } else {
2819                 /* The caller didn't specify a target, or the target was the
2820                  * same as the destination supplied during program load. This
2821                  * means we can reuse the trampoline and reference from program
2822                  * load time, and there is no need to allocate a new one. This
2823                  * can only happen once for any program, as the saved values in
2824                  * prog->aux are cleared below.
2825                  */
2826                 tr = prog->aux->dst_trampoline;
2827                 tgt_prog = prog->aux->dst_prog;
2828         }
2829
2830         err = bpf_link_prime(&link->link, &link_primer);
2831         if (err)
2832                 goto out_unlock;
2833
2834         err = bpf_trampoline_link_prog(prog, tr);
2835         if (err) {
2836                 bpf_link_cleanup(&link_primer);
2837                 link = NULL;
2838                 goto out_unlock;
2839         }
2840
2841         link->tgt_prog = tgt_prog;
2842         link->trampoline = tr;
2843
2844         /* Always clear the trampoline and target prog from prog->aux to make
2845          * sure the original attach destination is not kept alive after a
2846          * program is (re-)attached to another target.
2847          */
2848         if (prog->aux->dst_prog &&
2849             (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2850                 /* got extra prog ref from syscall, or attaching to different prog */
2851                 bpf_prog_put(prog->aux->dst_prog);
2852         if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2853                 /* we allocated a new trampoline, so free the old one */
2854                 bpf_trampoline_put(prog->aux->dst_trampoline);
2855
2856         prog->aux->dst_prog = NULL;
2857         prog->aux->dst_trampoline = NULL;
2858         mutex_unlock(&prog->aux->dst_mutex);
2859
2860         return bpf_link_settle(&link_primer);
2861 out_unlock:
2862         if (tr && tr != prog->aux->dst_trampoline)
2863                 bpf_trampoline_put(tr);
2864         mutex_unlock(&prog->aux->dst_mutex);
2865         kfree(link);
2866 out_put_prog:
2867         if (tgt_prog_fd && tgt_prog)
2868                 bpf_prog_put(tgt_prog);
2869         return err;
2870 }
2871
2872 struct bpf_raw_tp_link {
2873         struct bpf_link link;
2874         struct bpf_raw_event_map *btp;
2875 };
2876
2877 static void bpf_raw_tp_link_release(struct bpf_link *link)
2878 {
2879         struct bpf_raw_tp_link *raw_tp =
2880                 container_of(link, struct bpf_raw_tp_link, link);
2881
2882         bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2883         bpf_put_raw_tracepoint(raw_tp->btp);
2884 }
2885
2886 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2887 {
2888         struct bpf_raw_tp_link *raw_tp =
2889                 container_of(link, struct bpf_raw_tp_link, link);
2890
2891         kfree(raw_tp);
2892 }
2893
2894 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2895                                         struct seq_file *seq)
2896 {
2897         struct bpf_raw_tp_link *raw_tp_link =
2898                 container_of(link, struct bpf_raw_tp_link, link);
2899
2900         seq_printf(seq,
2901                    "tp_name:\t%s\n",
2902                    raw_tp_link->btp->tp->name);
2903 }
2904
2905 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2906                                           struct bpf_link_info *info)
2907 {
2908         struct bpf_raw_tp_link *raw_tp_link =
2909                 container_of(link, struct bpf_raw_tp_link, link);
2910         char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2911         const char *tp_name = raw_tp_link->btp->tp->name;
2912         u32 ulen = info->raw_tracepoint.tp_name_len;
2913         size_t tp_len = strlen(tp_name);
2914
2915         if (!ulen ^ !ubuf)
2916                 return -EINVAL;
2917
2918         info->raw_tracepoint.tp_name_len = tp_len + 1;
2919
2920         if (!ubuf)
2921                 return 0;
2922
2923         if (ulen >= tp_len + 1) {
2924                 if (copy_to_user(ubuf, tp_name, tp_len + 1))
2925                         return -EFAULT;
2926         } else {
2927                 char zero = '\0';
2928
2929                 if (copy_to_user(ubuf, tp_name, ulen - 1))
2930                         return -EFAULT;
2931                 if (put_user(zero, ubuf + ulen - 1))
2932                         return -EFAULT;
2933                 return -ENOSPC;
2934         }
2935
2936         return 0;
2937 }
2938
2939 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2940         .release = bpf_raw_tp_link_release,
2941         .dealloc = bpf_raw_tp_link_dealloc,
2942         .show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2943         .fill_link_info = bpf_raw_tp_link_fill_link_info,
2944 };
2945
2946 #ifdef CONFIG_PERF_EVENTS
2947 struct bpf_perf_link {
2948         struct bpf_link link;
2949         struct file *perf_file;
2950 };
2951
2952 static void bpf_perf_link_release(struct bpf_link *link)
2953 {
2954         struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2955         struct perf_event *event = perf_link->perf_file->private_data;
2956
2957         perf_event_free_bpf_prog(event);
2958         fput(perf_link->perf_file);
2959 }
2960
2961 static void bpf_perf_link_dealloc(struct bpf_link *link)
2962 {
2963         struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2964
2965         kfree(perf_link);
2966 }
2967
2968 static const struct bpf_link_ops bpf_perf_link_lops = {
2969         .release = bpf_perf_link_release,
2970         .dealloc = bpf_perf_link_dealloc,
2971 };
2972
2973 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2974 {
2975         struct bpf_link_primer link_primer;
2976         struct bpf_perf_link *link;
2977         struct perf_event *event;
2978         struct file *perf_file;
2979         int err;
2980
2981         if (attr->link_create.flags)
2982                 return -EINVAL;
2983
2984         perf_file = perf_event_get(attr->link_create.target_fd);
2985         if (IS_ERR(perf_file))
2986                 return PTR_ERR(perf_file);
2987
2988         link = kzalloc(sizeof(*link), GFP_USER);
2989         if (!link) {
2990                 err = -ENOMEM;
2991                 goto out_put_file;
2992         }
2993         bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2994         link->perf_file = perf_file;
2995
2996         err = bpf_link_prime(&link->link, &link_primer);
2997         if (err) {
2998                 kfree(link);
2999                 goto out_put_file;
3000         }
3001
3002         event = perf_file->private_data;
3003         err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3004         if (err) {
3005                 bpf_link_cleanup(&link_primer);
3006                 goto out_put_file;
3007         }
3008         /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3009         bpf_prog_inc(prog);
3010
3011         return bpf_link_settle(&link_primer);
3012
3013 out_put_file:
3014         fput(perf_file);
3015         return err;
3016 }
3017 #endif /* CONFIG_PERF_EVENTS */
3018
3019 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3020
3021 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3022 {
3023         struct bpf_link_primer link_primer;
3024         struct bpf_raw_tp_link *link;
3025         struct bpf_raw_event_map *btp;
3026         struct bpf_prog *prog;
3027         const char *tp_name;
3028         char buf[128];
3029         int err;
3030
3031         if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3032                 return -EINVAL;
3033
3034         prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3035         if (IS_ERR(prog))
3036                 return PTR_ERR(prog);
3037
3038         switch (prog->type) {
3039         case BPF_PROG_TYPE_TRACING:
3040         case BPF_PROG_TYPE_EXT:
3041         case BPF_PROG_TYPE_LSM:
3042                 if (attr->raw_tracepoint.name) {
3043                         /* The attach point for this category of programs
3044                          * should be specified via btf_id during program load.
3045                          */
3046                         err = -EINVAL;
3047                         goto out_put_prog;
3048                 }
3049                 if (prog->type == BPF_PROG_TYPE_TRACING &&
3050                     prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3051                         tp_name = prog->aux->attach_func_name;
3052                         break;
3053                 }
3054                 err = bpf_tracing_prog_attach(prog, 0, 0);
3055                 if (err >= 0)
3056                         return err;
3057                 goto out_put_prog;
3058         case BPF_PROG_TYPE_RAW_TRACEPOINT:
3059         case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3060                 if (strncpy_from_user(buf,
3061                                       u64_to_user_ptr(attr->raw_tracepoint.name),
3062                                       sizeof(buf) - 1) < 0) {
3063                         err = -EFAULT;
3064                         goto out_put_prog;
3065                 }
3066                 buf[sizeof(buf) - 1] = 0;
3067                 tp_name = buf;
3068                 break;
3069         default:
3070                 err = -EINVAL;
3071                 goto out_put_prog;
3072         }
3073
3074         btp = bpf_get_raw_tracepoint(tp_name);
3075         if (!btp) {
3076                 err = -ENOENT;
3077                 goto out_put_prog;
3078         }
3079
3080         link = kzalloc(sizeof(*link), GFP_USER);
3081         if (!link) {
3082                 err = -ENOMEM;
3083                 goto out_put_btp;
3084         }
3085         bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3086                       &bpf_raw_tp_link_lops, prog);
3087         link->btp = btp;
3088
3089         err = bpf_link_prime(&link->link, &link_primer);
3090         if (err) {
3091                 kfree(link);
3092                 goto out_put_btp;
3093         }
3094
3095         err = bpf_probe_register(link->btp, prog);
3096         if (err) {
3097                 bpf_link_cleanup(&link_primer);
3098                 goto out_put_btp;
3099         }
3100
3101         return bpf_link_settle(&link_primer);
3102
3103 out_put_btp:
3104         bpf_put_raw_tracepoint(btp);
3105 out_put_prog:
3106         bpf_prog_put(prog);
3107         return err;
3108 }
3109
3110 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3111                                              enum bpf_attach_type attach_type)
3112 {
3113         switch (prog->type) {
3114         case BPF_PROG_TYPE_CGROUP_SOCK:
3115         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3116         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3117         case BPF_PROG_TYPE_SK_LOOKUP:
3118                 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3119         case BPF_PROG_TYPE_CGROUP_SKB:
3120                 if (!capable(CAP_NET_ADMIN))
3121                         /* cg-skb progs can be loaded by unpriv user.
3122                          * check permissions at attach time.
3123                          */
3124                         return -EPERM;
3125                 return prog->enforce_expected_attach_type &&
3126                         prog->expected_attach_type != attach_type ?
3127                         -EINVAL : 0;
3128         default:
3129                 return 0;
3130         }
3131 }
3132
3133 static enum bpf_prog_type
3134 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3135 {
3136         switch (attach_type) {
3137         case BPF_CGROUP_INET_INGRESS:
3138         case BPF_CGROUP_INET_EGRESS:
3139                 return BPF_PROG_TYPE_CGROUP_SKB;
3140         case BPF_CGROUP_INET_SOCK_CREATE:
3141         case BPF_CGROUP_INET_SOCK_RELEASE:
3142         case BPF_CGROUP_INET4_POST_BIND:
3143         case BPF_CGROUP_INET6_POST_BIND:
3144                 return BPF_PROG_TYPE_CGROUP_SOCK;
3145         case BPF_CGROUP_INET4_BIND:
3146         case BPF_CGROUP_INET6_BIND:
3147         case BPF_CGROUP_INET4_CONNECT:
3148         case BPF_CGROUP_INET6_CONNECT:
3149         case BPF_CGROUP_INET4_GETPEERNAME:
3150         case BPF_CGROUP_INET6_GETPEERNAME:
3151         case BPF_CGROUP_INET4_GETSOCKNAME:
3152         case BPF_CGROUP_INET6_GETSOCKNAME:
3153         case BPF_CGROUP_UDP4_SENDMSG:
3154         case BPF_CGROUP_UDP6_SENDMSG:
3155         case BPF_CGROUP_UDP4_RECVMSG:
3156         case BPF_CGROUP_UDP6_RECVMSG:
3157                 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3158         case BPF_CGROUP_SOCK_OPS:
3159                 return BPF_PROG_TYPE_SOCK_OPS;
3160         case BPF_CGROUP_DEVICE:
3161                 return BPF_PROG_TYPE_CGROUP_DEVICE;
3162         case BPF_SK_MSG_VERDICT:
3163                 return BPF_PROG_TYPE_SK_MSG;
3164         case BPF_SK_SKB_STREAM_PARSER:
3165         case BPF_SK_SKB_STREAM_VERDICT:
3166         case BPF_SK_SKB_VERDICT:
3167                 return BPF_PROG_TYPE_SK_SKB;
3168         case BPF_LIRC_MODE2:
3169                 return BPF_PROG_TYPE_LIRC_MODE2;
3170         case BPF_FLOW_DISSECTOR:
3171                 return BPF_PROG_TYPE_FLOW_DISSECTOR;
3172         case BPF_CGROUP_SYSCTL:
3173                 return BPF_PROG_TYPE_CGROUP_SYSCTL;
3174         case BPF_CGROUP_GETSOCKOPT:
3175         case BPF_CGROUP_SETSOCKOPT:
3176                 return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3177         case BPF_TRACE_ITER:
3178                 return BPF_PROG_TYPE_TRACING;
3179         case BPF_SK_LOOKUP:
3180                 return BPF_PROG_TYPE_SK_LOOKUP;
3181         case BPF_XDP:
3182                 return BPF_PROG_TYPE_XDP;
3183         default:
3184                 return BPF_PROG_TYPE_UNSPEC;
3185         }
3186 }
3187
3188 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3189
3190 #define BPF_F_ATTACH_MASK \
3191         (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3192
3193 static int bpf_prog_attach(const union bpf_attr *attr)
3194 {
3195         enum bpf_prog_type ptype;
3196         struct bpf_prog *prog;
3197         int ret;
3198
3199         if (CHECK_ATTR(BPF_PROG_ATTACH))
3200                 return -EINVAL;
3201
3202         if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3203                 return -EINVAL;
3204
3205         ptype = attach_type_to_prog_type(attr->attach_type);
3206         if (ptype == BPF_PROG_TYPE_UNSPEC)
3207                 return -EINVAL;
3208
3209         prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3210         if (IS_ERR(prog))
3211                 return PTR_ERR(prog);
3212
3213         if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3214                 bpf_prog_put(prog);
3215                 return -EINVAL;
3216         }
3217
3218         switch (ptype) {
3219         case BPF_PROG_TYPE_SK_SKB:
3220         case BPF_PROG_TYPE_SK_MSG:
3221                 ret = sock_map_get_from_fd(attr, prog);
3222                 break;
3223         case BPF_PROG_TYPE_LIRC_MODE2:
3224                 ret = lirc_prog_attach(attr, prog);
3225                 break;
3226         case BPF_PROG_TYPE_FLOW_DISSECTOR:
3227                 ret = netns_bpf_prog_attach(attr, prog);
3228                 break;
3229         case BPF_PROG_TYPE_CGROUP_DEVICE:
3230         case BPF_PROG_TYPE_CGROUP_SKB:
3231         case BPF_PROG_TYPE_CGROUP_SOCK:
3232         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3233         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3234         case BPF_PROG_TYPE_CGROUP_SYSCTL:
3235         case BPF_PROG_TYPE_SOCK_OPS:
3236                 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3237                 break;
3238         default:
3239                 ret = -EINVAL;
3240         }
3241
3242         if (ret)
3243                 bpf_prog_put(prog);
3244         return ret;
3245 }
3246
3247 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3248
3249 static int bpf_prog_detach(const union bpf_attr *attr)
3250 {
3251         enum bpf_prog_type ptype;
3252
3253         if (CHECK_ATTR(BPF_PROG_DETACH))
3254                 return -EINVAL;
3255
3256         ptype = attach_type_to_prog_type(attr->attach_type);
3257
3258         switch (ptype) {
3259         case BPF_PROG_TYPE_SK_MSG:
3260         case BPF_PROG_TYPE_SK_SKB:
3261                 return sock_map_prog_detach(attr, ptype);
3262         case BPF_PROG_TYPE_LIRC_MODE2:
3263                 return lirc_prog_detach(attr);
3264         case BPF_PROG_TYPE_FLOW_DISSECTOR:
3265                 return netns_bpf_prog_detach(attr, ptype);
3266         case BPF_PROG_TYPE_CGROUP_DEVICE:
3267         case BPF_PROG_TYPE_CGROUP_SKB:
3268         case BPF_PROG_TYPE_CGROUP_SOCK:
3269         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3270         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3271         case BPF_PROG_TYPE_CGROUP_SYSCTL:
3272         case BPF_PROG_TYPE_SOCK_OPS:
3273                 return cgroup_bpf_prog_detach(attr, ptype);
3274         default:
3275                 return -EINVAL;
3276         }
3277 }
3278
3279 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3280
3281 static int bpf_prog_query(const union bpf_attr *attr,
3282                           union bpf_attr __user *uattr)
3283 {
3284         if (!capable(CAP_NET_ADMIN))
3285                 return -EPERM;
3286         if (CHECK_ATTR(BPF_PROG_QUERY))
3287                 return -EINVAL;
3288         if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3289                 return -EINVAL;
3290
3291         switch (attr->query.attach_type) {
3292         case BPF_CGROUP_INET_INGRESS:
3293         case BPF_CGROUP_INET_EGRESS:
3294         case BPF_CGROUP_INET_SOCK_CREATE:
3295         case BPF_CGROUP_INET_SOCK_RELEASE:
3296         case BPF_CGROUP_INET4_BIND:
3297         case BPF_CGROUP_INET6_BIND:
3298         case BPF_CGROUP_INET4_POST_BIND:
3299         case BPF_CGROUP_INET6_POST_BIND:
3300         case BPF_CGROUP_INET4_CONNECT:
3301         case BPF_CGROUP_INET6_CONNECT:
3302         case BPF_CGROUP_INET4_GETPEERNAME:
3303         case BPF_CGROUP_INET6_GETPEERNAME:
3304         case BPF_CGROUP_INET4_GETSOCKNAME:
3305         case BPF_CGROUP_INET6_GETSOCKNAME:
3306         case BPF_CGROUP_UDP4_SENDMSG:
3307         case BPF_CGROUP_UDP6_SENDMSG:
3308         case BPF_CGROUP_UDP4_RECVMSG:
3309         case BPF_CGROUP_UDP6_RECVMSG:
3310         case BPF_CGROUP_SOCK_OPS:
3311         case BPF_CGROUP_DEVICE:
3312         case BPF_CGROUP_SYSCTL:
3313         case BPF_CGROUP_GETSOCKOPT:
3314         case BPF_CGROUP_SETSOCKOPT:
3315                 return cgroup_bpf_prog_query(attr, uattr);
3316         case BPF_LIRC_MODE2:
3317                 return lirc_prog_query(attr, uattr);
3318         case BPF_FLOW_DISSECTOR:
3319         case BPF_SK_LOOKUP:
3320                 return netns_bpf_prog_query(attr, uattr);
3321         default:
3322                 return -EINVAL;
3323         }
3324 }
3325
3326 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3327
3328 static int bpf_prog_test_run(const union bpf_attr *attr,
3329                              union bpf_attr __user *uattr)
3330 {
3331         struct bpf_prog *prog;
3332         int ret = -ENOTSUPP;
3333
3334         if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3335                 return -EINVAL;
3336
3337         if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3338             (!attr->test.ctx_size_in && attr->test.ctx_in))
3339                 return -EINVAL;
3340
3341         if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3342             (!attr->test.ctx_size_out && attr->test.ctx_out))
3343                 return -EINVAL;
3344
3345         prog = bpf_prog_get(attr->test.prog_fd);
3346         if (IS_ERR(prog))
3347                 return PTR_ERR(prog);
3348
3349         if (prog->aux->ops->test_run)
3350                 ret = prog->aux->ops->test_run(prog, attr, uattr);
3351
3352         bpf_prog_put(prog);
3353         return ret;
3354 }
3355
3356 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3357
3358 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3359                                union bpf_attr __user *uattr,
3360                                struct idr *idr,
3361                                spinlock_t *lock)
3362 {
3363         u32 next_id = attr->start_id;
3364         int err = 0;
3365
3366         if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3367                 return -EINVAL;
3368
3369         if (!capable(CAP_SYS_ADMIN))
3370                 return -EPERM;
3371
3372         next_id++;
3373         spin_lock_bh(lock);
3374         if (!idr_get_next(idr, &next_id))
3375                 err = -ENOENT;
3376         spin_unlock_bh(lock);
3377
3378         if (!err)
3379                 err = put_user(next_id, &uattr->next_id);
3380
3381         return err;
3382 }
3383
3384 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3385 {
3386         struct bpf_map *map;
3387
3388         spin_lock_bh(&map_idr_lock);
3389 again:
3390         map = idr_get_next(&map_idr, id);
3391         if (map) {
3392                 map = __bpf_map_inc_not_zero(map, false);
3393                 if (IS_ERR(map)) {
3394                         (*id)++;
3395                         goto again;
3396                 }
3397         }
3398         spin_unlock_bh(&map_idr_lock);
3399
3400         return map;
3401 }
3402
3403 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3404 {
3405         struct bpf_prog *prog;
3406
3407         spin_lock_bh(&prog_idr_lock);
3408 again:
3409         prog = idr_get_next(&prog_idr, id);
3410         if (prog) {
3411                 prog = bpf_prog_inc_not_zero(prog);
3412                 if (IS_ERR(prog)) {
3413                         (*id)++;
3414                         goto again;
3415                 }
3416         }
3417         spin_unlock_bh(&prog_idr_lock);
3418
3419         return prog;
3420 }
3421
3422 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3423
3424 struct bpf_prog *bpf_prog_by_id(u32 id)
3425 {
3426         struct bpf_prog *prog;
3427
3428         if (!id)
3429                 return ERR_PTR(-ENOENT);
3430
3431         spin_lock_bh(&prog_idr_lock);
3432         prog = idr_find(&prog_idr, id);
3433         if (prog)
3434                 prog = bpf_prog_inc_not_zero(prog);
3435         else
3436                 prog = ERR_PTR(-ENOENT);
3437         spin_unlock_bh(&prog_idr_lock);
3438         return prog;
3439 }
3440
3441 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3442 {
3443         struct bpf_prog *prog;
3444         u32 id = attr->prog_id;
3445         int fd;
3446
3447         if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3448                 return -EINVAL;
3449
3450         if (!capable(CAP_SYS_ADMIN))
3451                 return -EPERM;
3452
3453         prog = bpf_prog_by_id(id);
3454         if (IS_ERR(prog))
3455                 return PTR_ERR(prog);
3456
3457         fd = bpf_prog_new_fd(prog);
3458         if (fd < 0)
3459                 bpf_prog_put(prog);
3460
3461         return fd;
3462 }
3463
3464 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3465
3466 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3467 {
3468         struct bpf_map *map;
3469         u32 id = attr->map_id;
3470         int f_flags;
3471         int fd;
3472
3473         if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3474             attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3475                 return -EINVAL;
3476
3477         if (!capable(CAP_SYS_ADMIN))
3478                 return -EPERM;
3479
3480         f_flags = bpf_get_file_flag(attr->open_flags);
3481         if (f_flags < 0)
3482                 return f_flags;
3483
3484         spin_lock_bh(&map_idr_lock);
3485         map = idr_find(&map_idr, id);
3486         if (map)
3487                 map = __bpf_map_inc_not_zero(map, true);
3488         else
3489                 map = ERR_PTR(-ENOENT);
3490         spin_unlock_bh(&map_idr_lock);
3491
3492         if (IS_ERR(map))
3493                 return PTR_ERR(map);
3494
3495         fd = bpf_map_new_fd(map, f_flags);
3496         if (fd < 0)
3497                 bpf_map_put_with_uref(map);
3498
3499         return fd;
3500 }
3501
3502 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3503                                               unsigned long addr, u32 *off,
3504                                               u32 *type)
3505 {
3506         const struct bpf_map *map;
3507         int i;
3508
3509         mutex_lock(&prog->aux->used_maps_mutex);
3510         for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3511                 map = prog->aux->used_maps[i];
3512                 if (map == (void *)addr) {
3513                         *type = BPF_PSEUDO_MAP_FD;
3514                         goto out;
3515                 }
3516                 if (!map->ops->map_direct_value_meta)
3517                         continue;
3518                 if (!map->ops->map_direct_value_meta(map, addr, off)) {
3519                         *type = BPF_PSEUDO_MAP_VALUE;
3520                         goto out;
3521                 }
3522         }
3523         map = NULL;
3524
3525 out:
3526         mutex_unlock(&prog->aux->used_maps_mutex);
3527         return map;
3528 }
3529
3530 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3531                                               const struct cred *f_cred)
3532 {
3533         const struct bpf_map *map;
3534         struct bpf_insn *insns;
3535         u32 off, type;
3536         u64 imm;
3537         u8 code;
3538         int i;
3539
3540         insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3541                         GFP_USER);
3542         if (!insns)
3543                 return insns;
3544
3545         for (i = 0; i < prog->len; i++) {
3546                 code = insns[i].code;
3547
3548                 if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3549                         insns[i].code = BPF_JMP | BPF_CALL;
3550                         insns[i].imm = BPF_FUNC_tail_call;
3551                         /* fall-through */
3552                 }
3553                 if (code == (BPF_JMP | BPF_CALL) ||
3554                     code == (BPF_JMP | BPF_CALL_ARGS)) {
3555                         if (code == (BPF_JMP | BPF_CALL_ARGS))
3556                                 insns[i].code = BPF_JMP | BPF_CALL;
3557                         if (!bpf_dump_raw_ok(f_cred))
3558                                 insns[i].imm = 0;
3559                         continue;
3560                 }
3561                 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3562                         insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3563                         continue;
3564                 }
3565
3566                 if (code != (BPF_LD | BPF_IMM | BPF_DW))
3567                         continue;
3568
3569                 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3570                 map = bpf_map_from_imm(prog, imm, &off, &type);
3571                 if (map) {
3572                         insns[i].src_reg = type;
3573                         insns[i].imm = map->id;
3574                         insns[i + 1].imm = off;
3575                         continue;
3576                 }
3577         }
3578
3579         return insns;
3580 }
3581
3582 static int set_info_rec_size(struct bpf_prog_info *info)
3583 {
3584         /*
3585          * Ensure info.*_rec_size is the same as kernel expected size
3586          *
3587          * or
3588          *
3589          * Only allow zero *_rec_size if both _rec_size and _cnt are
3590          * zero.  In this case, the kernel will set the expected
3591          * _rec_size back to the info.
3592          */
3593
3594         if ((info->nr_func_info || info->func_info_rec_size) &&
3595             info->func_info_rec_size != sizeof(struct bpf_func_info))
3596                 return -EINVAL;
3597
3598         if ((info->nr_line_info || info->line_info_rec_size) &&
3599             info->line_info_rec_size != sizeof(struct bpf_line_info))
3600                 return -EINVAL;
3601
3602         if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3603             info->jited_line_info_rec_size != sizeof(__u64))
3604                 return -EINVAL;
3605
3606         info->func_info_rec_size = sizeof(struct bpf_func_info);
3607         info->line_info_rec_size = sizeof(struct bpf_line_info);
3608         info->jited_line_info_rec_size = sizeof(__u64);
3609
3610         return 0;
3611 }
3612
3613 static int bpf_prog_get_info_by_fd(struct file *file,
3614                                    struct bpf_prog *prog,
3615                                    const union bpf_attr *attr,
3616                                    union bpf_attr __user *uattr)
3617 {
3618         struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3619         struct bpf_prog_info info;
3620         u32 info_len = attr->info.info_len;
3621         struct bpf_prog_kstats stats;
3622         char __user *uinsns;
3623         u32 ulen;
3624         int err;
3625
3626         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3627         if (err)
3628                 return err;
3629         info_len = min_t(u32, sizeof(info), info_len);
3630
3631         memset(&info, 0, sizeof(info));
3632         if (copy_from_user(&info, uinfo, info_len))
3633                 return -EFAULT;
3634
3635         info.type = prog->type;
3636         info.id = prog->aux->id;
3637         info.load_time = prog->aux->load_time;
3638         info.created_by_uid = from_kuid_munged(current_user_ns(),
3639                                                prog->aux->user->uid);
3640         info.gpl_compatible = prog->gpl_compatible;
3641
3642         memcpy(info.tag, prog->tag, sizeof(prog->tag));
3643         memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3644
3645         mutex_lock(&prog->aux->used_maps_mutex);
3646         ulen = info.nr_map_ids;
3647         info.nr_map_ids = prog->aux->used_map_cnt;
3648         ulen = min_t(u32, info.nr_map_ids, ulen);
3649         if (ulen) {
3650                 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3651                 u32 i;
3652
3653                 for (i = 0; i < ulen; i++)
3654                         if (put_user(prog->aux->used_maps[i]->id,
3655                                      &user_map_ids[i])) {
3656                                 mutex_unlock(&prog->aux->used_maps_mutex);
3657                                 return -EFAULT;
3658                         }
3659         }
3660         mutex_unlock(&prog->aux->used_maps_mutex);
3661
3662         err = set_info_rec_size(&info);
3663         if (err)
3664                 return err;
3665
3666         bpf_prog_get_stats(prog, &stats);
3667         info.run_time_ns = stats.nsecs;
3668         info.run_cnt = stats.cnt;
3669         info.recursion_misses = stats.misses;
3670
3671         info.verified_insns = prog->aux->verified_insns;
3672
3673         if (!bpf_capable()) {
3674                 info.jited_prog_len = 0;
3675                 info.xlated_prog_len = 0;
3676                 info.nr_jited_ksyms = 0;
3677                 info.nr_jited_func_lens = 0;
3678                 info.nr_func_info = 0;
3679                 info.nr_line_info = 0;
3680                 info.nr_jited_line_info = 0;
3681                 goto done;
3682         }
3683
3684         ulen = info.xlated_prog_len;
3685         info.xlated_prog_len = bpf_prog_insn_size(prog);
3686         if (info.xlated_prog_len && ulen) {
3687                 struct bpf_insn *insns_sanitized;
3688                 bool fault;
3689
3690                 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3691                         info.xlated_prog_insns = 0;
3692                         goto done;
3693                 }
3694                 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3695                 if (!insns_sanitized)
3696                         return -ENOMEM;
3697                 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3698                 ulen = min_t(u32, info.xlated_prog_len, ulen);
3699                 fault = copy_to_user(uinsns, insns_sanitized, ulen);
3700                 kfree(insns_sanitized);
3701                 if (fault)
3702                         return -EFAULT;
3703         }
3704
3705         if (bpf_prog_is_dev_bound(prog->aux)) {
3706                 err = bpf_prog_offload_info_fill(&info, prog);
3707                 if (err)
3708                         return err;
3709                 goto done;
3710         }
3711
3712         /* NOTE: the following code is supposed to be skipped for offload.
3713          * bpf_prog_offload_info_fill() is the place to fill similar fields
3714          * for offload.
3715          */
3716         ulen = info.jited_prog_len;
3717         if (prog->aux->func_cnt) {
3718                 u32 i;
3719
3720                 info.jited_prog_len = 0;
3721                 for (i = 0; i < prog->aux->func_cnt; i++)
3722                         info.jited_prog_len += prog->aux->func[i]->jited_len;
3723         } else {
3724                 info.jited_prog_len = prog->jited_len;
3725         }
3726
3727         if (info.jited_prog_len && ulen) {
3728                 if (bpf_dump_raw_ok(file->f_cred)) {
3729                         uinsns = u64_to_user_ptr(info.jited_prog_insns);
3730                         ulen = min_t(u32, info.jited_prog_len, ulen);
3731
3732                         /* for multi-function programs, copy the JITed
3733                          * instructions for all the functions
3734                          */
3735                         if (prog->aux->func_cnt) {
3736                                 u32 len, free, i;
3737                                 u8 *img;
3738
3739                                 free = ulen;
3740                                 for (i = 0; i < prog->aux->func_cnt; i++) {
3741                                         len = prog->aux->func[i]->jited_len;
3742                                         len = min_t(u32, len, free);
3743                                         img = (u8 *) prog->aux->func[i]->bpf_func;
3744                                         if (copy_to_user(uinsns, img, len))
3745                                                 return -EFAULT;
3746                                         uinsns += len;
3747                                         free -= len;
3748                                         if (!free)
3749                                                 break;
3750                                 }
3751                         } else {
3752                                 if (copy_to_user(uinsns, prog->bpf_func, ulen))
3753                                         return -EFAULT;
3754                         }
3755                 } else {
3756                         info.jited_prog_insns = 0;
3757                 }
3758         }
3759
3760         ulen = info.nr_jited_ksyms;
3761         info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3762         if (ulen) {
3763                 if (bpf_dump_raw_ok(file->f_cred)) {
3764                         unsigned long ksym_addr;
3765                         u64 __user *user_ksyms;
3766                         u32 i;
3767
3768                         /* copy the address of the kernel symbol
3769                          * corresponding to each function
3770                          */
3771                         ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3772                         user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3773                         if (prog->aux->func_cnt) {
3774                                 for (i = 0; i < ulen; i++) {
3775                                         ksym_addr = (unsigned long)
3776                                                 prog->aux->func[i]->bpf_func;
3777                                         if (put_user((u64) ksym_addr,
3778                                                      &user_ksyms[i]))
3779                                                 return -EFAULT;
3780                                 }
3781                         } else {
3782                                 ksym_addr = (unsigned long) prog->bpf_func;
3783                                 if (put_user((u64) ksym_addr, &user_ksyms[0]))
3784                                         return -EFAULT;
3785                         }
3786                 } else {
3787                         info.jited_ksyms = 0;
3788                 }
3789         }
3790
3791         ulen = info.nr_jited_func_lens;
3792         info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3793         if (ulen) {
3794                 if (bpf_dump_raw_ok(file->f_cred)) {
3795                         u32 __user *user_lens;
3796                         u32 func_len, i;
3797
3798                         /* copy the JITed image lengths for each function */
3799                         ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3800                         user_lens = u64_to_user_ptr(info.jited_func_lens);
3801                         if (prog->aux->func_cnt) {
3802                                 for (i = 0; i < ulen; i++) {
3803                                         func_len =
3804                                                 prog->aux->func[i]->jited_len;
3805                                         if (put_user(func_len, &user_lens[i]))
3806                                                 return -EFAULT;
3807                                 }
3808                         } else {
3809                                 func_len = prog->jited_len;
3810                                 if (put_user(func_len, &user_lens[0]))
3811                                         return -EFAULT;
3812                         }
3813                 } else {
3814                         info.jited_func_lens = 0;
3815                 }
3816         }
3817
3818         if (prog->aux->btf)
3819                 info.btf_id = btf_obj_id(prog->aux->btf);
3820
3821         ulen = info.nr_func_info;
3822         info.nr_func_info = prog->aux->func_info_cnt;
3823         if (info.nr_func_info && ulen) {
3824                 char __user *user_finfo;
3825
3826                 user_finfo = u64_to_user_ptr(info.func_info);
3827                 ulen = min_t(u32, info.nr_func_info, ulen);
3828                 if (copy_to_user(user_finfo, prog->aux->func_info,
3829                                  info.func_info_rec_size * ulen))
3830                         return -EFAULT;
3831         }
3832
3833         ulen = info.nr_line_info;
3834         info.nr_line_info = prog->aux->nr_linfo;
3835         if (info.nr_line_info && ulen) {
3836                 __u8 __user *user_linfo;
3837
3838                 user_linfo = u64_to_user_ptr(info.line_info);
3839                 ulen = min_t(u32, info.nr_line_info, ulen);
3840                 if (copy_to_user(user_linfo, prog->aux->linfo,
3841                                  info.line_info_rec_size * ulen))
3842                         return -EFAULT;
3843         }
3844
3845         ulen = info.nr_jited_line_info;
3846         if (prog->aux->jited_linfo)
3847                 info.nr_jited_line_info = prog->aux->nr_linfo;
3848         else
3849                 info.nr_jited_line_info = 0;
3850         if (info.nr_jited_line_info && ulen) {
3851                 if (bpf_dump_raw_ok(file->f_cred)) {
3852                         __u64 __user *user_linfo;
3853                         u32 i;
3854
3855                         user_linfo = u64_to_user_ptr(info.jited_line_info);
3856                         ulen = min_t(u32, info.nr_jited_line_info, ulen);
3857                         for (i = 0; i < ulen; i++) {
3858                                 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3859                                              &user_linfo[i]))
3860                                         return -EFAULT;
3861                         }
3862                 } else {
3863                         info.jited_line_info = 0;
3864                 }
3865         }
3866
3867         ulen = info.nr_prog_tags;
3868         info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3869         if (ulen) {
3870                 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3871                 u32 i;
3872
3873                 user_prog_tags = u64_to_user_ptr(info.prog_tags);
3874                 ulen = min_t(u32, info.nr_prog_tags, ulen);
3875                 if (prog->aux->func_cnt) {
3876                         for (i = 0; i < ulen; i++) {
3877                                 if (copy_to_user(user_prog_tags[i],
3878                                                  prog->aux->func[i]->tag,
3879                                                  BPF_TAG_SIZE))
3880                                         return -EFAULT;
3881                         }
3882                 } else {
3883                         if (copy_to_user(user_prog_tags[0],
3884                                          prog->tag, BPF_TAG_SIZE))
3885                                 return -EFAULT;
3886                 }
3887         }
3888
3889 done:
3890         if (copy_to_user(uinfo, &info, info_len) ||
3891             put_user(info_len, &uattr->info.info_len))
3892                 return -EFAULT;
3893
3894         return 0;
3895 }
3896
3897 static int bpf_map_get_info_by_fd(struct file *file,
3898                                   struct bpf_map *map,
3899                                   const union bpf_attr *attr,
3900                                   union bpf_attr __user *uattr)
3901 {
3902         struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3903         struct bpf_map_info info;
3904         u32 info_len = attr->info.info_len;
3905         int err;
3906
3907         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3908         if (err)
3909                 return err;
3910         info_len = min_t(u32, sizeof(info), info_len);
3911
3912         memset(&info, 0, sizeof(info));
3913         info.type = map->map_type;
3914         info.id = map->id;
3915         info.key_size = map->key_size;
3916         info.value_size = map->value_size;
3917         info.max_entries = map->max_entries;
3918         info.map_flags = map->map_flags;
3919         info.map_extra = map->map_extra;
3920         memcpy(info.name, map->name, sizeof(map->name));
3921
3922         if (map->btf) {
3923                 info.btf_id = btf_obj_id(map->btf);
3924                 info.btf_key_type_id = map->btf_key_type_id;
3925                 info.btf_value_type_id = map->btf_value_type_id;
3926         }
3927         info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3928
3929         if (bpf_map_is_dev_bound(map)) {
3930                 err = bpf_map_offload_info_fill(&info, map);
3931                 if (err)
3932                         return err;
3933         }
3934
3935         if (copy_to_user(uinfo, &info, info_len) ||
3936             put_user(info_len, &uattr->info.info_len))
3937                 return -EFAULT;
3938
3939         return 0;
3940 }
3941
3942 static int bpf_btf_get_info_by_fd(struct file *file,
3943                                   struct btf *btf,
3944                                   const union bpf_attr *attr,
3945                                   union bpf_attr __user *uattr)
3946 {
3947         struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3948         u32 info_len = attr->info.info_len;
3949         int err;
3950
3951         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3952         if (err)
3953                 return err;
3954
3955         return btf_get_info_by_fd(btf, attr, uattr);
3956 }
3957
3958 static int bpf_link_get_info_by_fd(struct file *file,
3959                                   struct bpf_link *link,
3960                                   const union bpf_attr *attr,
3961                                   union bpf_attr __user *uattr)
3962 {
3963         struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3964         struct bpf_link_info info;
3965         u32 info_len = attr->info.info_len;
3966         int err;
3967
3968         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3969         if (err)
3970                 return err;
3971         info_len = min_t(u32, sizeof(info), info_len);
3972
3973         memset(&info, 0, sizeof(info));
3974         if (copy_from_user(&info, uinfo, info_len))
3975                 return -EFAULT;
3976
3977         info.type = link->type;
3978         info.id = link->id;
3979         info.prog_id = link->prog->aux->id;
3980
3981         if (link->ops->fill_link_info) {
3982                 err = link->ops->fill_link_info(link, &info);
3983                 if (err)
3984                         return err;
3985         }
3986
3987         if (copy_to_user(uinfo, &info, info_len) ||
3988             put_user(info_len, &uattr->info.info_len))
3989                 return -EFAULT;
3990
3991         return 0;
3992 }
3993
3994
3995 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3996
3997 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
3998                                   union bpf_attr __user *uattr)
3999 {
4000         int ufd = attr->info.bpf_fd;
4001         struct fd f;
4002         int err;
4003
4004         if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
4005                 return -EINVAL;
4006
4007         f = fdget(ufd);
4008         if (!f.file)
4009                 return -EBADFD;
4010
4011         if (f.file->f_op == &bpf_prog_fops)
4012                 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
4013                                               uattr);
4014         else if (f.file->f_op == &bpf_map_fops)
4015                 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4016                                              uattr);
4017         else if (f.file->f_op == &btf_fops)
4018                 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4019         else if (f.file->f_op == &bpf_link_fops)
4020                 err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4021                                               attr, uattr);
4022         else
4023                 err = -EINVAL;
4024
4025         fdput(f);
4026         return err;
4027 }
4028
4029 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4030
4031 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4032 {
4033         if (CHECK_ATTR(BPF_BTF_LOAD))
4034                 return -EINVAL;
4035
4036         if (!bpf_capable())
4037                 return -EPERM;
4038
4039         return btf_new_fd(attr, uattr);
4040 }
4041
4042 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4043
4044 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4045 {
4046         if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4047                 return -EINVAL;
4048
4049         if (!capable(CAP_SYS_ADMIN))
4050                 return -EPERM;
4051
4052         return btf_get_fd_by_id(attr->btf_id);
4053 }
4054
4055 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4056                                     union bpf_attr __user *uattr,
4057                                     u32 prog_id, u32 fd_type,
4058                                     const char *buf, u64 probe_offset,
4059                                     u64 probe_addr)
4060 {
4061         char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4062         u32 len = buf ? strlen(buf) : 0, input_len;
4063         int err = 0;
4064
4065         if (put_user(len, &uattr->task_fd_query.buf_len))
4066                 return -EFAULT;
4067         input_len = attr->task_fd_query.buf_len;
4068         if (input_len && ubuf) {
4069                 if (!len) {
4070                         /* nothing to copy, just make ubuf NULL terminated */
4071                         char zero = '\0';
4072
4073                         if (put_user(zero, ubuf))
4074                                 return -EFAULT;
4075                 } else if (input_len >= len + 1) {
4076                         /* ubuf can hold the string with NULL terminator */
4077                         if (copy_to_user(ubuf, buf, len + 1))
4078                                 return -EFAULT;
4079                 } else {
4080                         /* ubuf cannot hold the string with NULL terminator,
4081                          * do a partial copy with NULL terminator.
4082                          */
4083                         char zero = '\0';
4084
4085                         err = -ENOSPC;
4086                         if (copy_to_user(ubuf, buf, input_len - 1))
4087                                 return -EFAULT;
4088                         if (put_user(zero, ubuf + input_len - 1))
4089                                 return -EFAULT;
4090                 }
4091         }
4092
4093         if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4094             put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4095             put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4096             put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4097                 return -EFAULT;
4098
4099         return err;
4100 }
4101
4102 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4103
4104 static int bpf_task_fd_query(const union bpf_attr *attr,
4105                              union bpf_attr __user *uattr)
4106 {
4107         pid_t pid = attr->task_fd_query.pid;
4108         u32 fd = attr->task_fd_query.fd;
4109         const struct perf_event *event;
4110         struct task_struct *task;
4111         struct file *file;
4112         int err;
4113
4114         if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4115                 return -EINVAL;
4116
4117         if (!capable(CAP_SYS_ADMIN))
4118                 return -EPERM;
4119
4120         if (attr->task_fd_query.flags != 0)
4121                 return -EINVAL;
4122
4123         task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4124         if (!task)
4125                 return -ENOENT;
4126
4127         err = 0;
4128         file = fget_task(task, fd);
4129         put_task_struct(task);
4130         if (!file)
4131                 return -EBADF;
4132
4133         if (file->f_op == &bpf_link_fops) {
4134                 struct bpf_link *link = file->private_data;
4135
4136                 if (link->ops == &bpf_raw_tp_link_lops) {
4137                         struct bpf_raw_tp_link *raw_tp =
4138                                 container_of(link, struct bpf_raw_tp_link, link);
4139                         struct bpf_raw_event_map *btp = raw_tp->btp;
4140
4141                         err = bpf_task_fd_query_copy(attr, uattr,
4142                                                      raw_tp->link.prog->aux->id,
4143                                                      BPF_FD_TYPE_RAW_TRACEPOINT,
4144                                                      btp->tp->name, 0, 0);
4145                         goto put_file;
4146                 }
4147                 goto out_not_supp;
4148         }
4149
4150         event = perf_get_event(file);
4151         if (!IS_ERR(event)) {
4152                 u64 probe_offset, probe_addr;
4153                 u32 prog_id, fd_type;
4154                 const char *buf;
4155
4156                 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4157                                               &buf, &probe_offset,
4158                                               &probe_addr);
4159                 if (!err)
4160                         err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4161                                                      fd_type, buf,
4162                                                      probe_offset,
4163                                                      probe_addr);
4164                 goto put_file;
4165         }
4166
4167 out_not_supp:
4168         err = -ENOTSUPP;
4169 put_file:
4170         fput(file);
4171         return err;
4172 }
4173
4174 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4175
4176 #define BPF_DO_BATCH(fn)                        \
4177         do {                                    \
4178                 if (!fn) {                      \
4179                         err = -ENOTSUPP;        \
4180                         goto err_put;           \
4181                 }                               \
4182                 err = fn(map, attr, uattr);     \
4183         } while (0)
4184
4185 static int bpf_map_do_batch(const union bpf_attr *attr,
4186                             union bpf_attr __user *uattr,
4187                             int cmd)
4188 {
4189         bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
4190                          cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
4191         bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
4192         struct bpf_map *map;
4193         int err, ufd;
4194         struct fd f;
4195
4196         if (CHECK_ATTR(BPF_MAP_BATCH))
4197                 return -EINVAL;
4198
4199         ufd = attr->batch.map_fd;
4200         f = fdget(ufd);
4201         map = __bpf_map_get(f);
4202         if (IS_ERR(map))
4203                 return PTR_ERR(map);
4204         if (has_write)
4205                 bpf_map_write_active_inc(map);
4206         if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4207                 err = -EPERM;
4208                 goto err_put;
4209         }
4210         if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4211                 err = -EPERM;
4212                 goto err_put;
4213         }
4214
4215         if (cmd == BPF_MAP_LOOKUP_BATCH)
4216                 BPF_DO_BATCH(map->ops->map_lookup_batch);
4217         else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4218                 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4219         else if (cmd == BPF_MAP_UPDATE_BATCH)
4220                 BPF_DO_BATCH(map->ops->map_update_batch);
4221         else
4222                 BPF_DO_BATCH(map->ops->map_delete_batch);
4223 err_put:
4224         if (has_write)
4225                 bpf_map_write_active_dec(map);
4226         fdput(f);
4227         return err;
4228 }
4229
4230 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4231                                    struct bpf_prog *prog)
4232 {
4233         if (attr->link_create.attach_type != prog->expected_attach_type)
4234                 return -EINVAL;
4235
4236         if (prog->expected_attach_type == BPF_TRACE_ITER)
4237                 return bpf_iter_link_attach(attr, uattr, prog);
4238         else if (prog->type == BPF_PROG_TYPE_EXT)
4239                 return bpf_tracing_prog_attach(prog,
4240                                                attr->link_create.target_fd,
4241                                                attr->link_create.target_btf_id);
4242         return -EINVAL;
4243 }
4244
4245 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4246 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4247 {
4248         enum bpf_prog_type ptype;
4249         struct bpf_prog *prog;
4250         int ret;
4251
4252         if (CHECK_ATTR(BPF_LINK_CREATE))
4253                 return -EINVAL;
4254
4255         prog = bpf_prog_get(attr->link_create.prog_fd);
4256         if (IS_ERR(prog))
4257                 return PTR_ERR(prog);
4258
4259         ret = bpf_prog_attach_check_attach_type(prog,
4260                                                 attr->link_create.attach_type);
4261         if (ret)
4262                 goto out;
4263
4264         switch (prog->type) {
4265         case BPF_PROG_TYPE_EXT:
4266                 ret = tracing_bpf_link_attach(attr, uattr, prog);
4267                 goto out;
4268         case BPF_PROG_TYPE_PERF_EVENT:
4269         case BPF_PROG_TYPE_KPROBE:
4270         case BPF_PROG_TYPE_TRACEPOINT:
4271                 if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4272                         ret = -EINVAL;
4273                         goto out;
4274                 }
4275                 ptype = prog->type;
4276                 break;
4277         default:
4278                 ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4279                 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4280                         ret = -EINVAL;
4281                         goto out;
4282                 }
4283                 break;
4284         }
4285
4286         switch (ptype) {
4287         case BPF_PROG_TYPE_CGROUP_SKB:
4288         case BPF_PROG_TYPE_CGROUP_SOCK:
4289         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4290         case BPF_PROG_TYPE_SOCK_OPS:
4291         case BPF_PROG_TYPE_CGROUP_DEVICE:
4292         case BPF_PROG_TYPE_CGROUP_SYSCTL:
4293         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4294                 ret = cgroup_bpf_link_attach(attr, prog);
4295                 break;
4296         case BPF_PROG_TYPE_TRACING:
4297                 ret = tracing_bpf_link_attach(attr, uattr, prog);
4298                 break;
4299         case BPF_PROG_TYPE_FLOW_DISSECTOR:
4300         case BPF_PROG_TYPE_SK_LOOKUP:
4301                 ret = netns_bpf_link_create(attr, prog);
4302                 break;
4303 #ifdef CONFIG_NET
4304         case BPF_PROG_TYPE_XDP:
4305                 ret = bpf_xdp_link_attach(attr, prog);
4306                 break;
4307 #endif
4308 #ifdef CONFIG_PERF_EVENTS
4309         case BPF_PROG_TYPE_PERF_EVENT:
4310         case BPF_PROG_TYPE_TRACEPOINT:
4311         case BPF_PROG_TYPE_KPROBE:
4312                 ret = bpf_perf_link_attach(attr, prog);
4313                 break;
4314 #endif
4315         default:
4316                 ret = -EINVAL;
4317         }
4318
4319 out:
4320         if (ret < 0)
4321                 bpf_prog_put(prog);
4322         return ret;
4323 }
4324
4325 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4326
4327 static int link_update(union bpf_attr *attr)
4328 {
4329         struct bpf_prog *old_prog = NULL, *new_prog;
4330         struct bpf_link *link;
4331         u32 flags;
4332         int ret;
4333
4334         if (CHECK_ATTR(BPF_LINK_UPDATE))
4335                 return -EINVAL;
4336
4337         flags = attr->link_update.flags;
4338         if (flags & ~BPF_F_REPLACE)
4339                 return -EINVAL;
4340
4341         link = bpf_link_get_from_fd(attr->link_update.link_fd);
4342         if (IS_ERR(link))
4343                 return PTR_ERR(link);
4344
4345         new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4346         if (IS_ERR(new_prog)) {
4347                 ret = PTR_ERR(new_prog);
4348                 goto out_put_link;
4349         }
4350
4351         if (flags & BPF_F_REPLACE) {
4352                 old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4353                 if (IS_ERR(old_prog)) {
4354                         ret = PTR_ERR(old_prog);
4355                         old_prog = NULL;
4356                         goto out_put_progs;
4357                 }
4358         } else if (attr->link_update.old_prog_fd) {
4359                 ret = -EINVAL;
4360                 goto out_put_progs;
4361         }
4362
4363         if (link->ops->update_prog)
4364                 ret = link->ops->update_prog(link, new_prog, old_prog);
4365         else
4366                 ret = -EINVAL;
4367
4368 out_put_progs:
4369         if (old_prog)
4370                 bpf_prog_put(old_prog);
4371         if (ret)
4372                 bpf_prog_put(new_prog);
4373 out_put_link:
4374         bpf_link_put(link);
4375         return ret;
4376 }
4377
4378 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4379
4380 static int link_detach(union bpf_attr *attr)
4381 {
4382         struct bpf_link *link;
4383         int ret;
4384
4385         if (CHECK_ATTR(BPF_LINK_DETACH))
4386                 return -EINVAL;
4387
4388         link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4389         if (IS_ERR(link))
4390                 return PTR_ERR(link);
4391
4392         if (link->ops->detach)
4393                 ret = link->ops->detach(link);
4394         else
4395                 ret = -EOPNOTSUPP;
4396
4397         bpf_link_put(link);
4398         return ret;
4399 }
4400
4401 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4402 {
4403         return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4404 }
4405
4406 struct bpf_link *bpf_link_by_id(u32 id)
4407 {
4408         struct bpf_link *link;
4409
4410         if (!id)
4411                 return ERR_PTR(-ENOENT);
4412
4413         spin_lock_bh(&link_idr_lock);
4414         /* before link is "settled", ID is 0, pretend it doesn't exist yet */
4415         link = idr_find(&link_idr, id);
4416         if (link) {
4417                 if (link->id)
4418                         link = bpf_link_inc_not_zero(link);
4419                 else
4420                         link = ERR_PTR(-EAGAIN);
4421         } else {
4422                 link = ERR_PTR(-ENOENT);
4423         }
4424         spin_unlock_bh(&link_idr_lock);
4425         return link;
4426 }
4427
4428 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4429
4430 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4431 {
4432         struct bpf_link *link;
4433         u32 id = attr->link_id;
4434         int fd;
4435
4436         if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4437                 return -EINVAL;
4438
4439         if (!capable(CAP_SYS_ADMIN))
4440                 return -EPERM;
4441
4442         link = bpf_link_by_id(id);
4443         if (IS_ERR(link))
4444                 return PTR_ERR(link);
4445
4446         fd = bpf_link_new_fd(link);
4447         if (fd < 0)
4448                 bpf_link_put(link);
4449
4450         return fd;
4451 }
4452
4453 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4454
4455 static int bpf_stats_release(struct inode *inode, struct file *file)
4456 {
4457         mutex_lock(&bpf_stats_enabled_mutex);
4458         static_key_slow_dec(&bpf_stats_enabled_key.key);
4459         mutex_unlock(&bpf_stats_enabled_mutex);
4460         return 0;
4461 }
4462
4463 static const struct file_operations bpf_stats_fops = {
4464         .release = bpf_stats_release,
4465 };
4466
4467 static int bpf_enable_runtime_stats(void)
4468 {
4469         int fd;
4470
4471         mutex_lock(&bpf_stats_enabled_mutex);
4472
4473         /* Set a very high limit to avoid overflow */
4474         if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4475                 mutex_unlock(&bpf_stats_enabled_mutex);
4476                 return -EBUSY;
4477         }
4478
4479         fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4480         if (fd >= 0)
4481                 static_key_slow_inc(&bpf_stats_enabled_key.key);
4482
4483         mutex_unlock(&bpf_stats_enabled_mutex);
4484         return fd;
4485 }
4486
4487 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4488
4489 static int bpf_enable_stats(union bpf_attr *attr)
4490 {
4491
4492         if (CHECK_ATTR(BPF_ENABLE_STATS))
4493                 return -EINVAL;
4494
4495         if (!capable(CAP_SYS_ADMIN))
4496                 return -EPERM;
4497
4498         switch (attr->enable_stats.type) {
4499         case BPF_STATS_RUN_TIME:
4500                 return bpf_enable_runtime_stats();
4501         default:
4502                 break;
4503         }
4504         return -EINVAL;
4505 }
4506
4507 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4508
4509 static int bpf_iter_create(union bpf_attr *attr)
4510 {
4511         struct bpf_link *link;
4512         int err;
4513
4514         if (CHECK_ATTR(BPF_ITER_CREATE))
4515                 return -EINVAL;
4516
4517         if (attr->iter_create.flags)
4518                 return -EINVAL;
4519
4520         link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4521         if (IS_ERR(link))
4522                 return PTR_ERR(link);
4523
4524         err = bpf_iter_new_fd(link);
4525         bpf_link_put(link);
4526
4527         return err;
4528 }
4529
4530 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4531
4532 static int bpf_prog_bind_map(union bpf_attr *attr)
4533 {
4534         struct bpf_prog *prog;
4535         struct bpf_map *map;
4536         struct bpf_map **used_maps_old, **used_maps_new;
4537         int i, ret = 0;
4538
4539         if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4540                 return -EINVAL;
4541
4542         if (attr->prog_bind_map.flags)
4543                 return -EINVAL;
4544
4545         prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4546         if (IS_ERR(prog))
4547                 return PTR_ERR(prog);
4548
4549         map = bpf_map_get(attr->prog_bind_map.map_fd);
4550         if (IS_ERR(map)) {
4551                 ret = PTR_ERR(map);
4552                 goto out_prog_put;
4553         }
4554
4555         mutex_lock(&prog->aux->used_maps_mutex);
4556
4557         used_maps_old = prog->aux->used_maps;
4558
4559         for (i = 0; i < prog->aux->used_map_cnt; i++)
4560                 if (used_maps_old[i] == map) {
4561                         bpf_map_put(map);
4562                         goto out_unlock;
4563                 }
4564
4565         used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4566                                       sizeof(used_maps_new[0]),
4567                                       GFP_KERNEL);
4568         if (!used_maps_new) {
4569                 ret = -ENOMEM;
4570                 goto out_unlock;
4571         }
4572
4573         memcpy(used_maps_new, used_maps_old,
4574                sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4575         used_maps_new[prog->aux->used_map_cnt] = map;
4576
4577         prog->aux->used_map_cnt++;
4578         prog->aux->used_maps = used_maps_new;
4579
4580         kfree(used_maps_old);
4581
4582 out_unlock:
4583         mutex_unlock(&prog->aux->used_maps_mutex);
4584
4585         if (ret)
4586                 bpf_map_put(map);
4587 out_prog_put:
4588         bpf_prog_put(prog);
4589         return ret;
4590 }
4591
4592 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4593 {
4594         union bpf_attr attr;
4595         int err;
4596
4597         if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4598                 return -EPERM;
4599
4600         err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4601         if (err)
4602                 return err;
4603         size = min_t(u32, size, sizeof(attr));
4604
4605         /* copy attributes from user space, may be less than sizeof(bpf_attr) */
4606         memset(&attr, 0, sizeof(attr));
4607         if (copy_from_bpfptr(&attr, uattr, size) != 0)
4608                 return -EFAULT;
4609
4610         err = security_bpf(cmd, &attr, size);
4611         if (err < 0)
4612                 return err;
4613
4614         switch (cmd) {
4615         case BPF_MAP_CREATE:
4616                 err = map_create(&attr);
4617                 break;
4618         case BPF_MAP_LOOKUP_ELEM:
4619                 err = map_lookup_elem(&attr);
4620                 break;
4621         case BPF_MAP_UPDATE_ELEM:
4622                 err = map_update_elem(&attr, uattr);
4623                 break;
4624         case BPF_MAP_DELETE_ELEM:
4625                 err = map_delete_elem(&attr);
4626                 break;
4627         case BPF_MAP_GET_NEXT_KEY:
4628                 err = map_get_next_key(&attr);
4629                 break;
4630         case BPF_MAP_FREEZE:
4631                 err = map_freeze(&attr);
4632                 break;
4633         case BPF_PROG_LOAD:
4634                 err = bpf_prog_load(&attr, uattr);
4635                 break;
4636         case BPF_OBJ_PIN:
4637                 err = bpf_obj_pin(&attr);
4638                 break;
4639         case BPF_OBJ_GET:
4640                 err = bpf_obj_get(&attr);
4641                 break;
4642         case BPF_PROG_ATTACH:
4643                 err = bpf_prog_attach(&attr);
4644                 break;
4645         case BPF_PROG_DETACH:
4646                 err = bpf_prog_detach(&attr);
4647                 break;
4648         case BPF_PROG_QUERY:
4649                 err = bpf_prog_query(&attr, uattr.user);
4650                 break;
4651         case BPF_PROG_TEST_RUN:
4652                 err = bpf_prog_test_run(&attr, uattr.user);
4653                 break;
4654         case BPF_PROG_GET_NEXT_ID:
4655                 err = bpf_obj_get_next_id(&attr, uattr.user,
4656                                           &prog_idr, &prog_idr_lock);
4657                 break;
4658         case BPF_MAP_GET_NEXT_ID:
4659                 err = bpf_obj_get_next_id(&attr, uattr.user,
4660                                           &map_idr, &map_idr_lock);
4661                 break;
4662         case BPF_BTF_GET_NEXT_ID:
4663                 err = bpf_obj_get_next_id(&attr, uattr.user,
4664                                           &btf_idr, &btf_idr_lock);
4665                 break;
4666         case BPF_PROG_GET_FD_BY_ID:
4667                 err = bpf_prog_get_fd_by_id(&attr);
4668                 break;
4669         case BPF_MAP_GET_FD_BY_ID:
4670                 err = bpf_map_get_fd_by_id(&attr);
4671                 break;
4672         case BPF_OBJ_GET_INFO_BY_FD:
4673                 err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4674                 break;
4675         case BPF_RAW_TRACEPOINT_OPEN:
4676                 err = bpf_raw_tracepoint_open(&attr);
4677                 break;
4678         case BPF_BTF_LOAD:
4679                 err = bpf_btf_load(&attr, uattr);
4680                 break;
4681         case BPF_BTF_GET_FD_BY_ID:
4682                 err = bpf_btf_get_fd_by_id(&attr);
4683                 break;
4684         case BPF_TASK_FD_QUERY:
4685                 err = bpf_task_fd_query(&attr, uattr.user);
4686                 break;
4687         case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4688                 err = map_lookup_and_delete_elem(&attr);
4689                 break;
4690         case BPF_MAP_LOOKUP_BATCH:
4691                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4692                 break;
4693         case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4694                 err = bpf_map_do_batch(&attr, uattr.user,
4695                                        BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4696                 break;
4697         case BPF_MAP_UPDATE_BATCH:
4698                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4699                 break;
4700         case BPF_MAP_DELETE_BATCH:
4701                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4702                 break;
4703         case BPF_LINK_CREATE:
4704                 err = link_create(&attr, uattr);
4705                 break;
4706         case BPF_LINK_UPDATE:
4707                 err = link_update(&attr);
4708                 break;
4709         case BPF_LINK_GET_FD_BY_ID:
4710                 err = bpf_link_get_fd_by_id(&attr);
4711                 break;
4712         case BPF_LINK_GET_NEXT_ID:
4713                 err = bpf_obj_get_next_id(&attr, uattr.user,
4714                                           &link_idr, &link_idr_lock);
4715                 break;
4716         case BPF_ENABLE_STATS:
4717                 err = bpf_enable_stats(&attr);
4718                 break;
4719         case BPF_ITER_CREATE:
4720                 err = bpf_iter_create(&attr);
4721                 break;
4722         case BPF_LINK_DETACH:
4723                 err = link_detach(&attr);
4724                 break;
4725         case BPF_PROG_BIND_MAP:
4726                 err = bpf_prog_bind_map(&attr);
4727                 break;
4728         default:
4729                 err = -EINVAL;
4730                 break;
4731         }
4732
4733         return err;
4734 }
4735
4736 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4737 {
4738         return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4739 }
4740
4741 static bool syscall_prog_is_valid_access(int off, int size,
4742                                          enum bpf_access_type type,
4743                                          const struct bpf_prog *prog,
4744                                          struct bpf_insn_access_aux *info)
4745 {
4746         if (off < 0 || off >= U16_MAX)
4747                 return false;
4748         if (off % size != 0)
4749                 return false;
4750         return true;
4751 }
4752
4753 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4754 {
4755         switch (cmd) {
4756         case BPF_MAP_CREATE:
4757         case BPF_MAP_UPDATE_ELEM:
4758         case BPF_MAP_FREEZE:
4759         case BPF_PROG_LOAD:
4760         case BPF_BTF_LOAD:
4761                 break;
4762         /* case BPF_PROG_TEST_RUN:
4763          * is not part of this list to prevent recursive test_run
4764          */
4765         default:
4766                 return -EINVAL;
4767         }
4768         return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4769 }
4770
4771 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4772         .func           = bpf_sys_bpf,
4773         .gpl_only       = false,
4774         .ret_type       = RET_INTEGER,
4775         .arg1_type      = ARG_ANYTHING,
4776         .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
4777         .arg3_type      = ARG_CONST_SIZE,
4778 };
4779
4780 const struct bpf_func_proto * __weak
4781 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4782 {
4783         return bpf_base_func_proto(func_id);
4784 }
4785
4786 BPF_CALL_1(bpf_sys_close, u32, fd)
4787 {
4788         /* When bpf program calls this helper there should not be
4789          * an fdget() without matching completed fdput().
4790          * This helper is allowed in the following callchain only:
4791          * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4792          */
4793         return close_fd(fd);
4794 }
4795
4796 static const struct bpf_func_proto bpf_sys_close_proto = {
4797         .func           = bpf_sys_close,
4798         .gpl_only       = false,
4799         .ret_type       = RET_INTEGER,
4800         .arg1_type      = ARG_ANYTHING,
4801 };
4802
4803 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
4804 {
4805         if (flags)
4806                 return -EINVAL;
4807
4808         if (name_sz <= 1 || name[name_sz - 1])
4809                 return -EINVAL;
4810
4811         if (!bpf_dump_raw_ok(current_cred()))
4812                 return -EPERM;
4813
4814         *res = kallsyms_lookup_name(name);
4815         return *res ? 0 : -ENOENT;
4816 }
4817
4818 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
4819         .func           = bpf_kallsyms_lookup_name,
4820         .gpl_only       = false,
4821         .ret_type       = RET_INTEGER,
4822         .arg1_type      = ARG_PTR_TO_MEM,
4823         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
4824         .arg3_type      = ARG_ANYTHING,
4825         .arg4_type      = ARG_PTR_TO_LONG,
4826 };
4827
4828 static const struct bpf_func_proto *
4829 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4830 {
4831         switch (func_id) {
4832         case BPF_FUNC_sys_bpf:
4833                 return &bpf_sys_bpf_proto;
4834         case BPF_FUNC_btf_find_by_name_kind:
4835                 return &bpf_btf_find_by_name_kind_proto;
4836         case BPF_FUNC_sys_close:
4837                 return &bpf_sys_close_proto;
4838         case BPF_FUNC_kallsyms_lookup_name:
4839                 return &bpf_kallsyms_lookup_name_proto;
4840         default:
4841                 return tracing_prog_func_proto(func_id, prog);
4842         }
4843 }
4844
4845 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4846         .get_func_proto  = syscall_prog_func_proto,
4847         .is_valid_access = syscall_prog_is_valid_access,
4848 };
4849
4850 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4851         .test_run = bpf_prog_test_run_syscall,
4852 };