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                 cond_resched();
1359         }
1360         if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1361                 err = -EFAULT;
1362
1363         kvfree(key);
1364         return err;
1365 }
1366
1367 int generic_map_update_batch(struct bpf_map *map,
1368                              const union bpf_attr *attr,
1369                              union bpf_attr __user *uattr)
1370 {
1371         void __user *values = u64_to_user_ptr(attr->batch.values);
1372         void __user *keys = u64_to_user_ptr(attr->batch.keys);
1373         u32 value_size, cp, max_count;
1374         int ufd = attr->batch.map_fd;
1375         void *key, *value;
1376         struct fd f;
1377         int err = 0;
1378
1379         if (attr->batch.elem_flags & ~BPF_F_LOCK)
1380                 return -EINVAL;
1381
1382         if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1383             !map_value_has_spin_lock(map)) {
1384                 return -EINVAL;
1385         }
1386
1387         value_size = bpf_map_value_size(map);
1388
1389         max_count = attr->batch.count;
1390         if (!max_count)
1391                 return 0;
1392
1393         key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1394         if (!key)
1395                 return -ENOMEM;
1396
1397         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1398         if (!value) {
1399                 kvfree(key);
1400                 return -ENOMEM;
1401         }
1402
1403         f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1404         for (cp = 0; cp < max_count; cp++) {
1405                 err = -EFAULT;
1406                 if (copy_from_user(key, keys + cp * map->key_size,
1407                     map->key_size) ||
1408                     copy_from_user(value, values + cp * value_size, value_size))
1409                         break;
1410
1411                 err = bpf_map_update_value(map, f, key, value,
1412                                            attr->batch.elem_flags);
1413
1414                 if (err)
1415                         break;
1416                 cond_resched();
1417         }
1418
1419         if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1420                 err = -EFAULT;
1421
1422         kvfree(value);
1423         kvfree(key);
1424         fdput(f);
1425         return err;
1426 }
1427
1428 #define MAP_LOOKUP_RETRIES 3
1429
1430 int generic_map_lookup_batch(struct bpf_map *map,
1431                                     const union bpf_attr *attr,
1432                                     union bpf_attr __user *uattr)
1433 {
1434         void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1435         void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1436         void __user *values = u64_to_user_ptr(attr->batch.values);
1437         void __user *keys = u64_to_user_ptr(attr->batch.keys);
1438         void *buf, *buf_prevkey, *prev_key, *key, *value;
1439         int err, retry = MAP_LOOKUP_RETRIES;
1440         u32 value_size, cp, max_count;
1441
1442         if (attr->batch.elem_flags & ~BPF_F_LOCK)
1443                 return -EINVAL;
1444
1445         if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1446             !map_value_has_spin_lock(map))
1447                 return -EINVAL;
1448
1449         value_size = bpf_map_value_size(map);
1450
1451         max_count = attr->batch.count;
1452         if (!max_count)
1453                 return 0;
1454
1455         if (put_user(0, &uattr->batch.count))
1456                 return -EFAULT;
1457
1458         buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1459         if (!buf_prevkey)
1460                 return -ENOMEM;
1461
1462         buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1463         if (!buf) {
1464                 kvfree(buf_prevkey);
1465                 return -ENOMEM;
1466         }
1467
1468         err = -EFAULT;
1469         prev_key = NULL;
1470         if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1471                 goto free_buf;
1472         key = buf;
1473         value = key + map->key_size;
1474         if (ubatch)
1475                 prev_key = buf_prevkey;
1476
1477         for (cp = 0; cp < max_count;) {
1478                 rcu_read_lock();
1479                 err = map->ops->map_get_next_key(map, prev_key, key);
1480                 rcu_read_unlock();
1481                 if (err)
1482                         break;
1483                 err = bpf_map_copy_value(map, key, value,
1484                                          attr->batch.elem_flags);
1485
1486                 if (err == -ENOENT) {
1487                         if (retry) {
1488                                 retry--;
1489                                 continue;
1490                         }
1491                         err = -EINTR;
1492                         break;
1493                 }
1494
1495                 if (err)
1496                         goto free_buf;
1497
1498                 if (copy_to_user(keys + cp * map->key_size, key,
1499                                  map->key_size)) {
1500                         err = -EFAULT;
1501                         goto free_buf;
1502                 }
1503                 if (copy_to_user(values + cp * value_size, value, value_size)) {
1504                         err = -EFAULT;
1505                         goto free_buf;
1506                 }
1507
1508                 if (!prev_key)
1509                         prev_key = buf_prevkey;
1510
1511                 swap(prev_key, key);
1512                 retry = MAP_LOOKUP_RETRIES;
1513                 cp++;
1514                 cond_resched();
1515         }
1516
1517         if (err == -EFAULT)
1518                 goto free_buf;
1519
1520         if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1521                     (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1522                 err = -EFAULT;
1523
1524 free_buf:
1525         kvfree(buf_prevkey);
1526         kvfree(buf);
1527         return err;
1528 }
1529
1530 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1531
1532 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1533 {
1534         void __user *ukey = u64_to_user_ptr(attr->key);
1535         void __user *uvalue = u64_to_user_ptr(attr->value);
1536         int ufd = attr->map_fd;
1537         struct bpf_map *map;
1538         void *key, *value;
1539         u32 value_size;
1540         struct fd f;
1541         int err;
1542
1543         if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1544                 return -EINVAL;
1545
1546         if (attr->flags & ~BPF_F_LOCK)
1547                 return -EINVAL;
1548
1549         f = fdget(ufd);
1550         map = __bpf_map_get(f);
1551         if (IS_ERR(map))
1552                 return PTR_ERR(map);
1553         bpf_map_write_active_inc(map);
1554         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1555             !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1556                 err = -EPERM;
1557                 goto err_put;
1558         }
1559
1560         if (attr->flags &&
1561             (map->map_type == BPF_MAP_TYPE_QUEUE ||
1562              map->map_type == BPF_MAP_TYPE_STACK)) {
1563                 err = -EINVAL;
1564                 goto err_put;
1565         }
1566
1567         if ((attr->flags & BPF_F_LOCK) &&
1568             !map_value_has_spin_lock(map)) {
1569                 err = -EINVAL;
1570                 goto err_put;
1571         }
1572
1573         key = __bpf_copy_key(ukey, map->key_size);
1574         if (IS_ERR(key)) {
1575                 err = PTR_ERR(key);
1576                 goto err_put;
1577         }
1578
1579         value_size = bpf_map_value_size(map);
1580
1581         err = -ENOMEM;
1582         value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1583         if (!value)
1584                 goto free_key;
1585
1586         err = -ENOTSUPP;
1587         if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1588             map->map_type == BPF_MAP_TYPE_STACK) {
1589                 err = map->ops->map_pop_elem(map, value);
1590         } else if (map->map_type == BPF_MAP_TYPE_HASH ||
1591                    map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1592                    map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1593                    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1594                 if (!bpf_map_is_dev_bound(map)) {
1595                         bpf_disable_instrumentation();
1596                         rcu_read_lock();
1597                         err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1598                         rcu_read_unlock();
1599                         bpf_enable_instrumentation();
1600                 }
1601         }
1602
1603         if (err)
1604                 goto free_value;
1605
1606         if (copy_to_user(uvalue, value, value_size) != 0) {
1607                 err = -EFAULT;
1608                 goto free_value;
1609         }
1610
1611         err = 0;
1612
1613 free_value:
1614         kvfree(value);
1615 free_key:
1616         kvfree(key);
1617 err_put:
1618         bpf_map_write_active_dec(map);
1619         fdput(f);
1620         return err;
1621 }
1622
1623 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1624
1625 static int map_freeze(const union bpf_attr *attr)
1626 {
1627         int err = 0, ufd = attr->map_fd;
1628         struct bpf_map *map;
1629         struct fd f;
1630
1631         if (CHECK_ATTR(BPF_MAP_FREEZE))
1632                 return -EINVAL;
1633
1634         f = fdget(ufd);
1635         map = __bpf_map_get(f);
1636         if (IS_ERR(map))
1637                 return PTR_ERR(map);
1638
1639         if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1640             map_value_has_timer(map)) {
1641                 fdput(f);
1642                 return -ENOTSUPP;
1643         }
1644
1645         mutex_lock(&map->freeze_mutex);
1646         if (bpf_map_write_active(map)) {
1647                 err = -EBUSY;
1648                 goto err_put;
1649         }
1650         if (READ_ONCE(map->frozen)) {
1651                 err = -EBUSY;
1652                 goto err_put;
1653         }
1654         if (!bpf_capable()) {
1655                 err = -EPERM;
1656                 goto err_put;
1657         }
1658
1659         WRITE_ONCE(map->frozen, true);
1660 err_put:
1661         mutex_unlock(&map->freeze_mutex);
1662         fdput(f);
1663         return err;
1664 }
1665
1666 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1667 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1668         [_id] = & _name ## _prog_ops,
1669 #define BPF_MAP_TYPE(_id, _ops)
1670 #define BPF_LINK_TYPE(_id, _name)
1671 #include <linux/bpf_types.h>
1672 #undef BPF_PROG_TYPE
1673 #undef BPF_MAP_TYPE
1674 #undef BPF_LINK_TYPE
1675 };
1676
1677 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1678 {
1679         const struct bpf_prog_ops *ops;
1680
1681         if (type >= ARRAY_SIZE(bpf_prog_types))
1682                 return -EINVAL;
1683         type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1684         ops = bpf_prog_types[type];
1685         if (!ops)
1686                 return -EINVAL;
1687
1688         if (!bpf_prog_is_dev_bound(prog->aux))
1689                 prog->aux->ops = ops;
1690         else
1691                 prog->aux->ops = &bpf_offload_prog_ops;
1692         prog->type = type;
1693         return 0;
1694 }
1695
1696 enum bpf_audit {
1697         BPF_AUDIT_LOAD,
1698         BPF_AUDIT_UNLOAD,
1699         BPF_AUDIT_MAX,
1700 };
1701
1702 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1703         [BPF_AUDIT_LOAD]   = "LOAD",
1704         [BPF_AUDIT_UNLOAD] = "UNLOAD",
1705 };
1706
1707 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1708 {
1709         struct audit_context *ctx = NULL;
1710         struct audit_buffer *ab;
1711
1712         if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1713                 return;
1714         if (audit_enabled == AUDIT_OFF)
1715                 return;
1716         if (op == BPF_AUDIT_LOAD)
1717                 ctx = audit_context();
1718         ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1719         if (unlikely(!ab))
1720                 return;
1721         audit_log_format(ab, "prog-id=%u op=%s",
1722                          prog->aux->id, bpf_audit_str[op]);
1723         audit_log_end(ab);
1724 }
1725
1726 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1727 {
1728         int id;
1729
1730         idr_preload(GFP_KERNEL);
1731         spin_lock_bh(&prog_idr_lock);
1732         id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1733         if (id > 0)
1734                 prog->aux->id = id;
1735         spin_unlock_bh(&prog_idr_lock);
1736         idr_preload_end();
1737
1738         /* id is in [1, INT_MAX) */
1739         if (WARN_ON_ONCE(!id))
1740                 return -ENOSPC;
1741
1742         return id > 0 ? 0 : id;
1743 }
1744
1745 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1746 {
1747         unsigned long flags;
1748
1749         /* cBPF to eBPF migrations are currently not in the idr store.
1750          * Offloaded programs are removed from the store when their device
1751          * disappears - even if someone grabs an fd to them they are unusable,
1752          * simply waiting for refcnt to drop to be freed.
1753          */
1754         if (!prog->aux->id)
1755                 return;
1756
1757         if (do_idr_lock)
1758                 spin_lock_irqsave(&prog_idr_lock, flags);
1759         else
1760                 __acquire(&prog_idr_lock);
1761
1762         idr_remove(&prog_idr, prog->aux->id);
1763         prog->aux->id = 0;
1764
1765         if (do_idr_lock)
1766                 spin_unlock_irqrestore(&prog_idr_lock, flags);
1767         else
1768                 __release(&prog_idr_lock);
1769 }
1770
1771 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1772 {
1773         struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1774
1775         kvfree(aux->func_info);
1776         kfree(aux->func_info_aux);
1777         free_uid(aux->user);
1778         security_bpf_prog_free(aux);
1779         bpf_prog_free(aux->prog);
1780 }
1781
1782 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1783 {
1784         bpf_prog_kallsyms_del_all(prog);
1785         btf_put(prog->aux->btf);
1786         kvfree(prog->aux->jited_linfo);
1787         kvfree(prog->aux->linfo);
1788         kfree(prog->aux->kfunc_tab);
1789         if (prog->aux->attach_btf)
1790                 btf_put(prog->aux->attach_btf);
1791
1792         if (deferred) {
1793                 if (prog->aux->sleepable)
1794                         call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1795                 else
1796                         call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1797         } else {
1798                 __bpf_prog_put_rcu(&prog->aux->rcu);
1799         }
1800 }
1801
1802 static void bpf_prog_put_deferred(struct work_struct *work)
1803 {
1804         struct bpf_prog_aux *aux;
1805         struct bpf_prog *prog;
1806
1807         aux = container_of(work, struct bpf_prog_aux, work);
1808         prog = aux->prog;
1809         perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1810         bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1811         __bpf_prog_put_noref(prog, true);
1812 }
1813
1814 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1815 {
1816         struct bpf_prog_aux *aux = prog->aux;
1817
1818         if (atomic64_dec_and_test(&aux->refcnt)) {
1819                 /* bpf_prog_free_id() must be called first */
1820                 bpf_prog_free_id(prog, do_idr_lock);
1821
1822                 if (in_irq() || irqs_disabled()) {
1823                         INIT_WORK(&aux->work, bpf_prog_put_deferred);
1824                         schedule_work(&aux->work);
1825                 } else {
1826                         bpf_prog_put_deferred(&aux->work);
1827                 }
1828         }
1829 }
1830
1831 void bpf_prog_put(struct bpf_prog *prog)
1832 {
1833         __bpf_prog_put(prog, true);
1834 }
1835 EXPORT_SYMBOL_GPL(bpf_prog_put);
1836
1837 static int bpf_prog_release(struct inode *inode, struct file *filp)
1838 {
1839         struct bpf_prog *prog = filp->private_data;
1840
1841         bpf_prog_put(prog);
1842         return 0;
1843 }
1844
1845 struct bpf_prog_kstats {
1846         u64 nsecs;
1847         u64 cnt;
1848         u64 misses;
1849 };
1850
1851 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1852                                struct bpf_prog_kstats *stats)
1853 {
1854         u64 nsecs = 0, cnt = 0, misses = 0;
1855         int cpu;
1856
1857         for_each_possible_cpu(cpu) {
1858                 const struct bpf_prog_stats *st;
1859                 unsigned int start;
1860                 u64 tnsecs, tcnt, tmisses;
1861
1862                 st = per_cpu_ptr(prog->stats, cpu);
1863                 do {
1864                         start = u64_stats_fetch_begin_irq(&st->syncp);
1865                         tnsecs = u64_stats_read(&st->nsecs);
1866                         tcnt = u64_stats_read(&st->cnt);
1867                         tmisses = u64_stats_read(&st->misses);
1868                 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1869                 nsecs += tnsecs;
1870                 cnt += tcnt;
1871                 misses += tmisses;
1872         }
1873         stats->nsecs = nsecs;
1874         stats->cnt = cnt;
1875         stats->misses = misses;
1876 }
1877
1878 #ifdef CONFIG_PROC_FS
1879 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1880 {
1881         const struct bpf_prog *prog = filp->private_data;
1882         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1883         struct bpf_prog_kstats stats;
1884
1885         bpf_prog_get_stats(prog, &stats);
1886         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1887         seq_printf(m,
1888                    "prog_type:\t%u\n"
1889                    "prog_jited:\t%u\n"
1890                    "prog_tag:\t%s\n"
1891                    "memlock:\t%llu\n"
1892                    "prog_id:\t%u\n"
1893                    "run_time_ns:\t%llu\n"
1894                    "run_cnt:\t%llu\n"
1895                    "recursion_misses:\t%llu\n"
1896                    "verified_insns:\t%u\n",
1897                    prog->type,
1898                    prog->jited,
1899                    prog_tag,
1900                    prog->pages * 1ULL << PAGE_SHIFT,
1901                    prog->aux->id,
1902                    stats.nsecs,
1903                    stats.cnt,
1904                    stats.misses,
1905                    prog->aux->verified_insns);
1906 }
1907 #endif
1908
1909 const struct file_operations bpf_prog_fops = {
1910 #ifdef CONFIG_PROC_FS
1911         .show_fdinfo    = bpf_prog_show_fdinfo,
1912 #endif
1913         .release        = bpf_prog_release,
1914         .read           = bpf_dummy_read,
1915         .write          = bpf_dummy_write,
1916 };
1917
1918 int bpf_prog_new_fd(struct bpf_prog *prog)
1919 {
1920         int ret;
1921
1922         ret = security_bpf_prog(prog);
1923         if (ret < 0)
1924                 return ret;
1925
1926         return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1927                                 O_RDWR | O_CLOEXEC);
1928 }
1929
1930 static struct bpf_prog *____bpf_prog_get(struct fd f)
1931 {
1932         if (!f.file)
1933                 return ERR_PTR(-EBADF);
1934         if (f.file->f_op != &bpf_prog_fops) {
1935                 fdput(f);
1936                 return ERR_PTR(-EINVAL);
1937         }
1938
1939         return f.file->private_data;
1940 }
1941
1942 void bpf_prog_add(struct bpf_prog *prog, int i)
1943 {
1944         atomic64_add(i, &prog->aux->refcnt);
1945 }
1946 EXPORT_SYMBOL_GPL(bpf_prog_add);
1947
1948 void bpf_prog_sub(struct bpf_prog *prog, int i)
1949 {
1950         /* Only to be used for undoing previous bpf_prog_add() in some
1951          * error path. We still know that another entity in our call
1952          * path holds a reference to the program, thus atomic_sub() can
1953          * be safely used in such cases!
1954          */
1955         WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1956 }
1957 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1958
1959 void bpf_prog_inc(struct bpf_prog *prog)
1960 {
1961         atomic64_inc(&prog->aux->refcnt);
1962 }
1963 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1964
1965 /* prog_idr_lock should have been held */
1966 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1967 {
1968         int refold;
1969
1970         refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1971
1972         if (!refold)
1973                 return ERR_PTR(-ENOENT);
1974
1975         return prog;
1976 }
1977 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1978
1979 bool bpf_prog_get_ok(struct bpf_prog *prog,
1980                             enum bpf_prog_type *attach_type, bool attach_drv)
1981 {
1982         /* not an attachment, just a refcount inc, always allow */
1983         if (!attach_type)
1984                 return true;
1985
1986         if (prog->type != *attach_type)
1987                 return false;
1988         if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1989                 return false;
1990
1991         return true;
1992 }
1993
1994 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1995                                        bool attach_drv)
1996 {
1997         struct fd f = fdget(ufd);
1998         struct bpf_prog *prog;
1999
2000         prog = ____bpf_prog_get(f);
2001         if (IS_ERR(prog))
2002                 return prog;
2003         if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
2004                 prog = ERR_PTR(-EINVAL);
2005                 goto out;
2006         }
2007
2008         bpf_prog_inc(prog);
2009 out:
2010         fdput(f);
2011         return prog;
2012 }
2013
2014 struct bpf_prog *bpf_prog_get(u32 ufd)
2015 {
2016         return __bpf_prog_get(ufd, NULL, false);
2017 }
2018
2019 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2020                                        bool attach_drv)
2021 {
2022         return __bpf_prog_get(ufd, &type, attach_drv);
2023 }
2024 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2025
2026 /* Initially all BPF programs could be loaded w/o specifying
2027  * expected_attach_type. Later for some of them specifying expected_attach_type
2028  * at load time became required so that program could be validated properly.
2029  * Programs of types that are allowed to be loaded both w/ and w/o (for
2030  * backward compatibility) expected_attach_type, should have the default attach
2031  * type assigned to expected_attach_type for the latter case, so that it can be
2032  * validated later at attach time.
2033  *
2034  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2035  * prog type requires it but has some attach types that have to be backward
2036  * compatible.
2037  */
2038 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2039 {
2040         switch (attr->prog_type) {
2041         case BPF_PROG_TYPE_CGROUP_SOCK:
2042                 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2043                  * exist so checking for non-zero is the way to go here.
2044                  */
2045                 if (!attr->expected_attach_type)
2046                         attr->expected_attach_type =
2047                                 BPF_CGROUP_INET_SOCK_CREATE;
2048                 break;
2049         case BPF_PROG_TYPE_SK_REUSEPORT:
2050                 if (!attr->expected_attach_type)
2051                         attr->expected_attach_type =
2052                                 BPF_SK_REUSEPORT_SELECT;
2053                 break;
2054         }
2055 }
2056
2057 static int
2058 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2059                            enum bpf_attach_type expected_attach_type,
2060                            struct btf *attach_btf, u32 btf_id,
2061                            struct bpf_prog *dst_prog)
2062 {
2063         if (btf_id) {
2064                 if (btf_id > BTF_MAX_TYPE)
2065                         return -EINVAL;
2066
2067                 if (!attach_btf && !dst_prog)
2068                         return -EINVAL;
2069
2070                 switch (prog_type) {
2071                 case BPF_PROG_TYPE_TRACING:
2072                 case BPF_PROG_TYPE_LSM:
2073                 case BPF_PROG_TYPE_STRUCT_OPS:
2074                 case BPF_PROG_TYPE_EXT:
2075                         break;
2076                 default:
2077                         return -EINVAL;
2078                 }
2079         }
2080
2081         if (attach_btf && (!btf_id || dst_prog))
2082                 return -EINVAL;
2083
2084         if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2085             prog_type != BPF_PROG_TYPE_EXT)
2086                 return -EINVAL;
2087
2088         switch (prog_type) {
2089         case BPF_PROG_TYPE_CGROUP_SOCK:
2090                 switch (expected_attach_type) {
2091                 case BPF_CGROUP_INET_SOCK_CREATE:
2092                 case BPF_CGROUP_INET_SOCK_RELEASE:
2093                 case BPF_CGROUP_INET4_POST_BIND:
2094                 case BPF_CGROUP_INET6_POST_BIND:
2095                         return 0;
2096                 default:
2097                         return -EINVAL;
2098                 }
2099         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2100                 switch (expected_attach_type) {
2101                 case BPF_CGROUP_INET4_BIND:
2102                 case BPF_CGROUP_INET6_BIND:
2103                 case BPF_CGROUP_INET4_CONNECT:
2104                 case BPF_CGROUP_INET6_CONNECT:
2105                 case BPF_CGROUP_INET4_GETPEERNAME:
2106                 case BPF_CGROUP_INET6_GETPEERNAME:
2107                 case BPF_CGROUP_INET4_GETSOCKNAME:
2108                 case BPF_CGROUP_INET6_GETSOCKNAME:
2109                 case BPF_CGROUP_UDP4_SENDMSG:
2110                 case BPF_CGROUP_UDP6_SENDMSG:
2111                 case BPF_CGROUP_UDP4_RECVMSG:
2112                 case BPF_CGROUP_UDP6_RECVMSG:
2113                         return 0;
2114                 default:
2115                         return -EINVAL;
2116                 }
2117         case BPF_PROG_TYPE_CGROUP_SKB:
2118                 switch (expected_attach_type) {
2119                 case BPF_CGROUP_INET_INGRESS:
2120                 case BPF_CGROUP_INET_EGRESS:
2121                         return 0;
2122                 default:
2123                         return -EINVAL;
2124                 }
2125         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2126                 switch (expected_attach_type) {
2127                 case BPF_CGROUP_SETSOCKOPT:
2128                 case BPF_CGROUP_GETSOCKOPT:
2129                         return 0;
2130                 default:
2131                         return -EINVAL;
2132                 }
2133         case BPF_PROG_TYPE_SK_LOOKUP:
2134                 if (expected_attach_type == BPF_SK_LOOKUP)
2135                         return 0;
2136                 return -EINVAL;
2137         case BPF_PROG_TYPE_SK_REUSEPORT:
2138                 switch (expected_attach_type) {
2139                 case BPF_SK_REUSEPORT_SELECT:
2140                 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2141                         return 0;
2142                 default:
2143                         return -EINVAL;
2144                 }
2145         case BPF_PROG_TYPE_SYSCALL:
2146         case BPF_PROG_TYPE_EXT:
2147                 if (expected_attach_type)
2148                         return -EINVAL;
2149                 fallthrough;
2150         default:
2151                 return 0;
2152         }
2153 }
2154
2155 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2156 {
2157         switch (prog_type) {
2158         case BPF_PROG_TYPE_SCHED_CLS:
2159         case BPF_PROG_TYPE_SCHED_ACT:
2160         case BPF_PROG_TYPE_XDP:
2161         case BPF_PROG_TYPE_LWT_IN:
2162         case BPF_PROG_TYPE_LWT_OUT:
2163         case BPF_PROG_TYPE_LWT_XMIT:
2164         case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2165         case BPF_PROG_TYPE_SK_SKB:
2166         case BPF_PROG_TYPE_SK_MSG:
2167         case BPF_PROG_TYPE_LIRC_MODE2:
2168         case BPF_PROG_TYPE_FLOW_DISSECTOR:
2169         case BPF_PROG_TYPE_CGROUP_DEVICE:
2170         case BPF_PROG_TYPE_CGROUP_SOCK:
2171         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2172         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2173         case BPF_PROG_TYPE_CGROUP_SYSCTL:
2174         case BPF_PROG_TYPE_SOCK_OPS:
2175         case BPF_PROG_TYPE_EXT: /* extends any prog */
2176                 return true;
2177         case BPF_PROG_TYPE_CGROUP_SKB:
2178                 /* always unpriv */
2179         case BPF_PROG_TYPE_SK_REUSEPORT:
2180                 /* equivalent to SOCKET_FILTER. need CAP_BPF only */
2181         default:
2182                 return false;
2183         }
2184 }
2185
2186 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2187 {
2188         switch (prog_type) {
2189         case BPF_PROG_TYPE_KPROBE:
2190         case BPF_PROG_TYPE_TRACEPOINT:
2191         case BPF_PROG_TYPE_PERF_EVENT:
2192         case BPF_PROG_TYPE_RAW_TRACEPOINT:
2193         case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2194         case BPF_PROG_TYPE_TRACING:
2195         case BPF_PROG_TYPE_LSM:
2196         case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2197         case BPF_PROG_TYPE_EXT: /* extends any prog */
2198                 return true;
2199         default:
2200                 return false;
2201         }
2202 }
2203
2204 /* last field in 'union bpf_attr' used by this command */
2205 #define BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
2206
2207 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2208 {
2209         enum bpf_prog_type type = attr->prog_type;
2210         struct bpf_prog *prog, *dst_prog = NULL;
2211         struct btf *attach_btf = NULL;
2212         int err;
2213         char license[128];
2214         bool is_gpl;
2215
2216         if (CHECK_ATTR(BPF_PROG_LOAD))
2217                 return -EINVAL;
2218
2219         if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2220                                  BPF_F_ANY_ALIGNMENT |
2221                                  BPF_F_TEST_STATE_FREQ |
2222                                  BPF_F_SLEEPABLE |
2223                                  BPF_F_TEST_RND_HI32))
2224                 return -EINVAL;
2225
2226         if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2227             (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2228             !bpf_capable())
2229                 return -EPERM;
2230
2231         /* copy eBPF program license from user space */
2232         if (strncpy_from_bpfptr(license,
2233                                 make_bpfptr(attr->license, uattr.is_kernel),
2234                                 sizeof(license) - 1) < 0)
2235                 return -EFAULT;
2236         license[sizeof(license) - 1] = 0;
2237
2238         /* eBPF programs must be GPL compatible to use GPL-ed functions */
2239         is_gpl = license_is_gpl_compatible(license);
2240
2241         if (attr->insn_cnt == 0 ||
2242             attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2243                 return -E2BIG;
2244         if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2245             type != BPF_PROG_TYPE_CGROUP_SKB &&
2246             !bpf_capable())
2247                 return -EPERM;
2248
2249         if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2250                 return -EPERM;
2251         if (is_perfmon_prog_type(type) && !perfmon_capable())
2252                 return -EPERM;
2253
2254         /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2255          * or btf, we need to check which one it is
2256          */
2257         if (attr->attach_prog_fd) {
2258                 dst_prog = bpf_prog_get(attr->attach_prog_fd);
2259                 if (IS_ERR(dst_prog)) {
2260                         dst_prog = NULL;
2261                         attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2262                         if (IS_ERR(attach_btf))
2263                                 return -EINVAL;
2264                         if (!btf_is_kernel(attach_btf)) {
2265                                 /* attaching through specifying bpf_prog's BTF
2266                                  * objects directly might be supported eventually
2267                                  */
2268                                 btf_put(attach_btf);
2269                                 return -ENOTSUPP;
2270                         }
2271                 }
2272         } else if (attr->attach_btf_id) {
2273                 /* fall back to vmlinux BTF, if BTF type ID is specified */
2274                 attach_btf = bpf_get_btf_vmlinux();
2275                 if (IS_ERR(attach_btf))
2276                         return PTR_ERR(attach_btf);
2277                 if (!attach_btf)
2278                         return -EINVAL;
2279                 btf_get(attach_btf);
2280         }
2281
2282         bpf_prog_load_fixup_attach_type(attr);
2283         if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2284                                        attach_btf, attr->attach_btf_id,
2285                                        dst_prog)) {
2286                 if (dst_prog)
2287                         bpf_prog_put(dst_prog);
2288                 if (attach_btf)
2289                         btf_put(attach_btf);
2290                 return -EINVAL;
2291         }
2292
2293         /* plain bpf_prog allocation */
2294         prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2295         if (!prog) {
2296                 if (dst_prog)
2297                         bpf_prog_put(dst_prog);
2298                 if (attach_btf)
2299                         btf_put(attach_btf);
2300                 return -ENOMEM;
2301         }
2302
2303         prog->expected_attach_type = attr->expected_attach_type;
2304         prog->aux->attach_btf = attach_btf;
2305         prog->aux->attach_btf_id = attr->attach_btf_id;
2306         prog->aux->dst_prog = dst_prog;
2307         prog->aux->offload_requested = !!attr->prog_ifindex;
2308         prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2309
2310         err = security_bpf_prog_alloc(prog->aux);
2311         if (err)
2312                 goto free_prog;
2313
2314         prog->aux->user = get_current_user();
2315         prog->len = attr->insn_cnt;
2316
2317         err = -EFAULT;
2318         if (copy_from_bpfptr(prog->insns,
2319                              make_bpfptr(attr->insns, uattr.is_kernel),
2320                              bpf_prog_insn_size(prog)) != 0)
2321                 goto free_prog_sec;
2322
2323         prog->orig_prog = NULL;
2324         prog->jited = 0;
2325
2326         atomic64_set(&prog->aux->refcnt, 1);
2327         prog->gpl_compatible = is_gpl ? 1 : 0;
2328
2329         if (bpf_prog_is_dev_bound(prog->aux)) {
2330                 err = bpf_prog_offload_init(prog, attr);
2331                 if (err)
2332                         goto free_prog_sec;
2333         }
2334
2335         /* find program type: socket_filter vs tracing_filter */
2336         err = find_prog_type(type, prog);
2337         if (err < 0)
2338                 goto free_prog_sec;
2339
2340         prog->aux->load_time = ktime_get_boottime_ns();
2341         err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2342                                sizeof(attr->prog_name));
2343         if (err < 0)
2344                 goto free_prog_sec;
2345
2346         /* run eBPF verifier */
2347         err = bpf_check(&prog, attr, uattr);
2348         if (err < 0)
2349                 goto free_used_maps;
2350
2351         prog = bpf_prog_select_runtime(prog, &err);
2352         if (err < 0)
2353                 goto free_used_maps;
2354
2355         err = bpf_prog_alloc_id(prog);
2356         if (err)
2357                 goto free_used_maps;
2358
2359         /* Upon success of bpf_prog_alloc_id(), the BPF prog is
2360          * effectively publicly exposed. However, retrieving via
2361          * bpf_prog_get_fd_by_id() will take another reference,
2362          * therefore it cannot be gone underneath us.
2363          *
2364          * Only for the time /after/ successful bpf_prog_new_fd()
2365          * and before returning to userspace, we might just hold
2366          * one reference and any parallel close on that fd could
2367          * rip everything out. Hence, below notifications must
2368          * happen before bpf_prog_new_fd().
2369          *
2370          * Also, any failure handling from this point onwards must
2371          * be using bpf_prog_put() given the program is exposed.
2372          */
2373         bpf_prog_kallsyms_add(prog);
2374         perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2375         bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2376
2377         err = bpf_prog_new_fd(prog);
2378         if (err < 0)
2379                 bpf_prog_put(prog);
2380         return err;
2381
2382 free_used_maps:
2383         /* In case we have subprogs, we need to wait for a grace
2384          * period before we can tear down JIT memory since symbols
2385          * are already exposed under kallsyms.
2386          */
2387         __bpf_prog_put_noref(prog, prog->aux->func_cnt);
2388         return err;
2389 free_prog_sec:
2390         free_uid(prog->aux->user);
2391         security_bpf_prog_free(prog->aux);
2392 free_prog:
2393         if (prog->aux->attach_btf)
2394                 btf_put(prog->aux->attach_btf);
2395         bpf_prog_free(prog);
2396         return err;
2397 }
2398
2399 #define BPF_OBJ_LAST_FIELD file_flags
2400
2401 static int bpf_obj_pin(const union bpf_attr *attr)
2402 {
2403         if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2404                 return -EINVAL;
2405
2406         return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2407 }
2408
2409 static int bpf_obj_get(const union bpf_attr *attr)
2410 {
2411         if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2412             attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2413                 return -EINVAL;
2414
2415         return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2416                                 attr->file_flags);
2417 }
2418
2419 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2420                    const struct bpf_link_ops *ops, struct bpf_prog *prog)
2421 {
2422         atomic64_set(&link->refcnt, 1);
2423         link->type = type;
2424         link->id = 0;
2425         link->ops = ops;
2426         link->prog = prog;
2427 }
2428
2429 static void bpf_link_free_id(int id)
2430 {
2431         if (!id)
2432                 return;
2433
2434         spin_lock_bh(&link_idr_lock);
2435         idr_remove(&link_idr, id);
2436         spin_unlock_bh(&link_idr_lock);
2437 }
2438
2439 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2440  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2441  * anon_inode's release() call. This helper marksbpf_link as
2442  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2443  * is not decremented, it's the responsibility of a calling code that failed
2444  * to complete bpf_link initialization.
2445  */
2446 void bpf_link_cleanup(struct bpf_link_primer *primer)
2447 {
2448         primer->link->prog = NULL;
2449         bpf_link_free_id(primer->id);
2450         fput(primer->file);
2451         put_unused_fd(primer->fd);
2452 }
2453
2454 void bpf_link_inc(struct bpf_link *link)
2455 {
2456         atomic64_inc(&link->refcnt);
2457 }
2458
2459 /* bpf_link_free is guaranteed to be called from process context */
2460 static void bpf_link_free(struct bpf_link *link)
2461 {
2462         bpf_link_free_id(link->id);
2463         if (link->prog) {
2464                 /* detach BPF program, clean up used resources */
2465                 link->ops->release(link);
2466                 bpf_prog_put(link->prog);
2467         }
2468         /* free bpf_link and its containing memory */
2469         link->ops->dealloc(link);
2470 }
2471
2472 static void bpf_link_put_deferred(struct work_struct *work)
2473 {
2474         struct bpf_link *link = container_of(work, struct bpf_link, work);
2475
2476         bpf_link_free(link);
2477 }
2478
2479 /* bpf_link_put can be called from atomic context, but ensures that resources
2480  * are freed from process context
2481  */
2482 void bpf_link_put(struct bpf_link *link)
2483 {
2484         if (!atomic64_dec_and_test(&link->refcnt))
2485                 return;
2486
2487         if (in_atomic()) {
2488                 INIT_WORK(&link->work, bpf_link_put_deferred);
2489                 schedule_work(&link->work);
2490         } else {
2491                 bpf_link_free(link);
2492         }
2493 }
2494
2495 static int bpf_link_release(struct inode *inode, struct file *filp)
2496 {
2497         struct bpf_link *link = filp->private_data;
2498
2499         bpf_link_put(link);
2500         return 0;
2501 }
2502
2503 #ifdef CONFIG_PROC_FS
2504 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2505 #define BPF_MAP_TYPE(_id, _ops)
2506 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2507 static const char *bpf_link_type_strs[] = {
2508         [BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2509 #include <linux/bpf_types.h>
2510 };
2511 #undef BPF_PROG_TYPE
2512 #undef BPF_MAP_TYPE
2513 #undef BPF_LINK_TYPE
2514
2515 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2516 {
2517         const struct bpf_link *link = filp->private_data;
2518         const struct bpf_prog *prog = link->prog;
2519         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2520
2521         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2522         seq_printf(m,
2523                    "link_type:\t%s\n"
2524                    "link_id:\t%u\n"
2525                    "prog_tag:\t%s\n"
2526                    "prog_id:\t%u\n",
2527                    bpf_link_type_strs[link->type],
2528                    link->id,
2529                    prog_tag,
2530                    prog->aux->id);
2531         if (link->ops->show_fdinfo)
2532                 link->ops->show_fdinfo(link, m);
2533 }
2534 #endif
2535
2536 static const struct file_operations bpf_link_fops = {
2537 #ifdef CONFIG_PROC_FS
2538         .show_fdinfo    = bpf_link_show_fdinfo,
2539 #endif
2540         .release        = bpf_link_release,
2541         .read           = bpf_dummy_read,
2542         .write          = bpf_dummy_write,
2543 };
2544
2545 static int bpf_link_alloc_id(struct bpf_link *link)
2546 {
2547         int id;
2548
2549         idr_preload(GFP_KERNEL);
2550         spin_lock_bh(&link_idr_lock);
2551         id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2552         spin_unlock_bh(&link_idr_lock);
2553         idr_preload_end();
2554
2555         return id;
2556 }
2557
2558 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2559  * reserving unused FD and allocating ID from link_idr. This is to be paired
2560  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2561  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2562  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2563  * transient state is passed around in struct bpf_link_primer.
2564  * This is preferred way to create and initialize bpf_link, especially when
2565  * there are complicated and expensive operations inbetween creating bpf_link
2566  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2567  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2568  * expensive (and potentially failing) roll back operations in a rare case
2569  * that file, FD, or ID can't be allocated.
2570  */
2571 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2572 {
2573         struct file *file;
2574         int fd, id;
2575
2576         fd = get_unused_fd_flags(O_CLOEXEC);
2577         if (fd < 0)
2578                 return fd;
2579
2580
2581         id = bpf_link_alloc_id(link);
2582         if (id < 0) {
2583                 put_unused_fd(fd);
2584                 return id;
2585         }
2586
2587         file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2588         if (IS_ERR(file)) {
2589                 bpf_link_free_id(id);
2590                 put_unused_fd(fd);
2591                 return PTR_ERR(file);
2592         }
2593
2594         primer->link = link;
2595         primer->file = file;
2596         primer->fd = fd;
2597         primer->id = id;
2598         return 0;
2599 }
2600
2601 int bpf_link_settle(struct bpf_link_primer *primer)
2602 {
2603         /* make bpf_link fetchable by ID */
2604         spin_lock_bh(&link_idr_lock);
2605         primer->link->id = primer->id;
2606         spin_unlock_bh(&link_idr_lock);
2607         /* make bpf_link fetchable by FD */
2608         fd_install(primer->fd, primer->file);
2609         /* pass through installed FD */
2610         return primer->fd;
2611 }
2612
2613 int bpf_link_new_fd(struct bpf_link *link)
2614 {
2615         return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2616 }
2617
2618 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2619 {
2620         struct fd f = fdget(ufd);
2621         struct bpf_link *link;
2622
2623         if (!f.file)
2624                 return ERR_PTR(-EBADF);
2625         if (f.file->f_op != &bpf_link_fops) {
2626                 fdput(f);
2627                 return ERR_PTR(-EINVAL);
2628         }
2629
2630         link = f.file->private_data;
2631         bpf_link_inc(link);
2632         fdput(f);
2633
2634         return link;
2635 }
2636
2637 struct bpf_tracing_link {
2638         struct bpf_link link;
2639         enum bpf_attach_type attach_type;
2640         struct bpf_trampoline *trampoline;
2641         struct bpf_prog *tgt_prog;
2642 };
2643
2644 static void bpf_tracing_link_release(struct bpf_link *link)
2645 {
2646         struct bpf_tracing_link *tr_link =
2647                 container_of(link, struct bpf_tracing_link, link);
2648
2649         WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2650                                                 tr_link->trampoline));
2651
2652         bpf_trampoline_put(tr_link->trampoline);
2653
2654         /* tgt_prog is NULL if target is a kernel function */
2655         if (tr_link->tgt_prog)
2656                 bpf_prog_put(tr_link->tgt_prog);
2657 }
2658
2659 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2660 {
2661         struct bpf_tracing_link *tr_link =
2662                 container_of(link, struct bpf_tracing_link, link);
2663
2664         kfree(tr_link);
2665 }
2666
2667 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2668                                          struct seq_file *seq)
2669 {
2670         struct bpf_tracing_link *tr_link =
2671                 container_of(link, struct bpf_tracing_link, link);
2672
2673         seq_printf(seq,
2674                    "attach_type:\t%d\n",
2675                    tr_link->attach_type);
2676 }
2677
2678 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2679                                            struct bpf_link_info *info)
2680 {
2681         struct bpf_tracing_link *tr_link =
2682                 container_of(link, struct bpf_tracing_link, link);
2683
2684         info->tracing.attach_type = tr_link->attach_type;
2685         bpf_trampoline_unpack_key(tr_link->trampoline->key,
2686                                   &info->tracing.target_obj_id,
2687                                   &info->tracing.target_btf_id);
2688
2689         return 0;
2690 }
2691
2692 static const struct bpf_link_ops bpf_tracing_link_lops = {
2693         .release = bpf_tracing_link_release,
2694         .dealloc = bpf_tracing_link_dealloc,
2695         .show_fdinfo = bpf_tracing_link_show_fdinfo,
2696         .fill_link_info = bpf_tracing_link_fill_link_info,
2697 };
2698
2699 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2700                                    int tgt_prog_fd,
2701                                    u32 btf_id)
2702 {
2703         struct bpf_link_primer link_primer;
2704         struct bpf_prog *tgt_prog = NULL;
2705         struct bpf_trampoline *tr = NULL;
2706         struct bpf_tracing_link *link;
2707         u64 key = 0;
2708         int err;
2709
2710         switch (prog->type) {
2711         case BPF_PROG_TYPE_TRACING:
2712                 if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2713                     prog->expected_attach_type != BPF_TRACE_FEXIT &&
2714                     prog->expected_attach_type != BPF_MODIFY_RETURN) {
2715                         err = -EINVAL;
2716                         goto out_put_prog;
2717                 }
2718                 break;
2719         case BPF_PROG_TYPE_EXT:
2720                 if (prog->expected_attach_type != 0) {
2721                         err = -EINVAL;
2722                         goto out_put_prog;
2723                 }
2724                 break;
2725         case BPF_PROG_TYPE_LSM:
2726                 if (prog->expected_attach_type != BPF_LSM_MAC) {
2727                         err = -EINVAL;
2728                         goto out_put_prog;
2729                 }
2730                 break;
2731         default:
2732                 err = -EINVAL;
2733                 goto out_put_prog;
2734         }
2735
2736         if (!!tgt_prog_fd != !!btf_id) {
2737                 err = -EINVAL;
2738                 goto out_put_prog;
2739         }
2740
2741         if (tgt_prog_fd) {
2742                 /* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2743                 if (prog->type != BPF_PROG_TYPE_EXT) {
2744                         err = -EINVAL;
2745                         goto out_put_prog;
2746                 }
2747
2748                 tgt_prog = bpf_prog_get(tgt_prog_fd);
2749                 if (IS_ERR(tgt_prog)) {
2750                         err = PTR_ERR(tgt_prog);
2751                         tgt_prog = NULL;
2752                         goto out_put_prog;
2753                 }
2754
2755                 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2756         }
2757
2758         link = kzalloc(sizeof(*link), GFP_USER);
2759         if (!link) {
2760                 err = -ENOMEM;
2761                 goto out_put_prog;
2762         }
2763         bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2764                       &bpf_tracing_link_lops, prog);
2765         link->attach_type = prog->expected_attach_type;
2766
2767         mutex_lock(&prog->aux->dst_mutex);
2768
2769         /* There are a few possible cases here:
2770          *
2771          * - if prog->aux->dst_trampoline is set, the program was just loaded
2772          *   and not yet attached to anything, so we can use the values stored
2773          *   in prog->aux
2774          *
2775          * - if prog->aux->dst_trampoline is NULL, the program has already been
2776          *   attached to a target and its initial target was cleared (below)
2777          *
2778          * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2779          *   target_btf_id using the link_create API.
2780          *
2781          * - if tgt_prog == NULL when this function was called using the old
2782          *   raw_tracepoint_open API, and we need a target from prog->aux
2783          *
2784          * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2785          *   was detached and is going for re-attachment.
2786          */
2787         if (!prog->aux->dst_trampoline && !tgt_prog) {
2788                 /*
2789                  * Allow re-attach for TRACING and LSM programs. If it's
2790                  * currently linked, bpf_trampoline_link_prog will fail.
2791                  * EXT programs need to specify tgt_prog_fd, so they
2792                  * re-attach in separate code path.
2793                  */
2794                 if (prog->type != BPF_PROG_TYPE_TRACING &&
2795                     prog->type != BPF_PROG_TYPE_LSM) {
2796                         err = -EINVAL;
2797                         goto out_unlock;
2798                 }
2799                 btf_id = prog->aux->attach_btf_id;
2800                 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2801         }
2802
2803         if (!prog->aux->dst_trampoline ||
2804             (key && key != prog->aux->dst_trampoline->key)) {
2805                 /* If there is no saved target, or the specified target is
2806                  * different from the destination specified at load time, we
2807                  * need a new trampoline and a check for compatibility
2808                  */
2809                 struct bpf_attach_target_info tgt_info = {};
2810
2811                 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2812                                               &tgt_info);
2813                 if (err)
2814                         goto out_unlock;
2815
2816                 tr = bpf_trampoline_get(key, &tgt_info);
2817                 if (!tr) {
2818                         err = -ENOMEM;
2819                         goto out_unlock;
2820                 }
2821         } else {
2822                 /* The caller didn't specify a target, or the target was the
2823                  * same as the destination supplied during program load. This
2824                  * means we can reuse the trampoline and reference from program
2825                  * load time, and there is no need to allocate a new one. This
2826                  * can only happen once for any program, as the saved values in
2827                  * prog->aux are cleared below.
2828                  */
2829                 tr = prog->aux->dst_trampoline;
2830                 tgt_prog = prog->aux->dst_prog;
2831         }
2832
2833         err = bpf_link_prime(&link->link, &link_primer);
2834         if (err)
2835                 goto out_unlock;
2836
2837         err = bpf_trampoline_link_prog(prog, tr);
2838         if (err) {
2839                 bpf_link_cleanup(&link_primer);
2840                 link = NULL;
2841                 goto out_unlock;
2842         }
2843
2844         link->tgt_prog = tgt_prog;
2845         link->trampoline = tr;
2846
2847         /* Always clear the trampoline and target prog from prog->aux to make
2848          * sure the original attach destination is not kept alive after a
2849          * program is (re-)attached to another target.
2850          */
2851         if (prog->aux->dst_prog &&
2852             (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2853                 /* got extra prog ref from syscall, or attaching to different prog */
2854                 bpf_prog_put(prog->aux->dst_prog);
2855         if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2856                 /* we allocated a new trampoline, so free the old one */
2857                 bpf_trampoline_put(prog->aux->dst_trampoline);
2858
2859         prog->aux->dst_prog = NULL;
2860         prog->aux->dst_trampoline = NULL;
2861         mutex_unlock(&prog->aux->dst_mutex);
2862
2863         return bpf_link_settle(&link_primer);
2864 out_unlock:
2865         if (tr && tr != prog->aux->dst_trampoline)
2866                 bpf_trampoline_put(tr);
2867         mutex_unlock(&prog->aux->dst_mutex);
2868         kfree(link);
2869 out_put_prog:
2870         if (tgt_prog_fd && tgt_prog)
2871                 bpf_prog_put(tgt_prog);
2872         return err;
2873 }
2874
2875 struct bpf_raw_tp_link {
2876         struct bpf_link link;
2877         struct bpf_raw_event_map *btp;
2878 };
2879
2880 static void bpf_raw_tp_link_release(struct bpf_link *link)
2881 {
2882         struct bpf_raw_tp_link *raw_tp =
2883                 container_of(link, struct bpf_raw_tp_link, link);
2884
2885         bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2886         bpf_put_raw_tracepoint(raw_tp->btp);
2887 }
2888
2889 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2890 {
2891         struct bpf_raw_tp_link *raw_tp =
2892                 container_of(link, struct bpf_raw_tp_link, link);
2893
2894         kfree(raw_tp);
2895 }
2896
2897 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2898                                         struct seq_file *seq)
2899 {
2900         struct bpf_raw_tp_link *raw_tp_link =
2901                 container_of(link, struct bpf_raw_tp_link, link);
2902
2903         seq_printf(seq,
2904                    "tp_name:\t%s\n",
2905                    raw_tp_link->btp->tp->name);
2906 }
2907
2908 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2909                                           struct bpf_link_info *info)
2910 {
2911         struct bpf_raw_tp_link *raw_tp_link =
2912                 container_of(link, struct bpf_raw_tp_link, link);
2913         char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2914         const char *tp_name = raw_tp_link->btp->tp->name;
2915         u32 ulen = info->raw_tracepoint.tp_name_len;
2916         size_t tp_len = strlen(tp_name);
2917
2918         if (!ulen ^ !ubuf)
2919                 return -EINVAL;
2920
2921         info->raw_tracepoint.tp_name_len = tp_len + 1;
2922
2923         if (!ubuf)
2924                 return 0;
2925
2926         if (ulen >= tp_len + 1) {
2927                 if (copy_to_user(ubuf, tp_name, tp_len + 1))
2928                         return -EFAULT;
2929         } else {
2930                 char zero = '\0';
2931
2932                 if (copy_to_user(ubuf, tp_name, ulen - 1))
2933                         return -EFAULT;
2934                 if (put_user(zero, ubuf + ulen - 1))
2935                         return -EFAULT;
2936                 return -ENOSPC;
2937         }
2938
2939         return 0;
2940 }
2941
2942 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2943         .release = bpf_raw_tp_link_release,
2944         .dealloc = bpf_raw_tp_link_dealloc,
2945         .show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2946         .fill_link_info = bpf_raw_tp_link_fill_link_info,
2947 };
2948
2949 #ifdef CONFIG_PERF_EVENTS
2950 struct bpf_perf_link {
2951         struct bpf_link link;
2952         struct file *perf_file;
2953 };
2954
2955 static void bpf_perf_link_release(struct bpf_link *link)
2956 {
2957         struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2958         struct perf_event *event = perf_link->perf_file->private_data;
2959
2960         perf_event_free_bpf_prog(event);
2961         fput(perf_link->perf_file);
2962 }
2963
2964 static void bpf_perf_link_dealloc(struct bpf_link *link)
2965 {
2966         struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2967
2968         kfree(perf_link);
2969 }
2970
2971 static const struct bpf_link_ops bpf_perf_link_lops = {
2972         .release = bpf_perf_link_release,
2973         .dealloc = bpf_perf_link_dealloc,
2974 };
2975
2976 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2977 {
2978         struct bpf_link_primer link_primer;
2979         struct bpf_perf_link *link;
2980         struct perf_event *event;
2981         struct file *perf_file;
2982         int err;
2983
2984         if (attr->link_create.flags)
2985                 return -EINVAL;
2986
2987         perf_file = perf_event_get(attr->link_create.target_fd);
2988         if (IS_ERR(perf_file))
2989                 return PTR_ERR(perf_file);
2990
2991         link = kzalloc(sizeof(*link), GFP_USER);
2992         if (!link) {
2993                 err = -ENOMEM;
2994                 goto out_put_file;
2995         }
2996         bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2997         link->perf_file = perf_file;
2998
2999         err = bpf_link_prime(&link->link, &link_primer);
3000         if (err) {
3001                 kfree(link);
3002                 goto out_put_file;
3003         }
3004
3005         event = perf_file->private_data;
3006         err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3007         if (err) {
3008                 bpf_link_cleanup(&link_primer);
3009                 goto out_put_file;
3010         }
3011         /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3012         bpf_prog_inc(prog);
3013
3014         return bpf_link_settle(&link_primer);
3015
3016 out_put_file:
3017         fput(perf_file);
3018         return err;
3019 }
3020 #endif /* CONFIG_PERF_EVENTS */
3021
3022 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3023
3024 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3025 {
3026         struct bpf_link_primer link_primer;
3027         struct bpf_raw_tp_link *link;
3028         struct bpf_raw_event_map *btp;
3029         struct bpf_prog *prog;
3030         const char *tp_name;
3031         char buf[128];
3032         int err;
3033
3034         if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3035                 return -EINVAL;
3036
3037         prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3038         if (IS_ERR(prog))
3039                 return PTR_ERR(prog);
3040
3041         switch (prog->type) {
3042         case BPF_PROG_TYPE_TRACING:
3043         case BPF_PROG_TYPE_EXT:
3044         case BPF_PROG_TYPE_LSM:
3045                 if (attr->raw_tracepoint.name) {
3046                         /* The attach point for this category of programs
3047                          * should be specified via btf_id during program load.
3048                          */
3049                         err = -EINVAL;
3050                         goto out_put_prog;
3051                 }
3052                 if (prog->type == BPF_PROG_TYPE_TRACING &&
3053                     prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3054                         tp_name = prog->aux->attach_func_name;
3055                         break;
3056                 }
3057                 err = bpf_tracing_prog_attach(prog, 0, 0);
3058                 if (err >= 0)
3059                         return err;
3060                 goto out_put_prog;
3061         case BPF_PROG_TYPE_RAW_TRACEPOINT:
3062         case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3063                 if (strncpy_from_user(buf,
3064                                       u64_to_user_ptr(attr->raw_tracepoint.name),
3065                                       sizeof(buf) - 1) < 0) {
3066                         err = -EFAULT;
3067                         goto out_put_prog;
3068                 }
3069                 buf[sizeof(buf) - 1] = 0;
3070                 tp_name = buf;
3071                 break;
3072         default:
3073                 err = -EINVAL;
3074                 goto out_put_prog;
3075         }
3076
3077         btp = bpf_get_raw_tracepoint(tp_name);
3078         if (!btp) {
3079                 err = -ENOENT;
3080                 goto out_put_prog;
3081         }
3082
3083         link = kzalloc(sizeof(*link), GFP_USER);
3084         if (!link) {
3085                 err = -ENOMEM;
3086                 goto out_put_btp;
3087         }
3088         bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3089                       &bpf_raw_tp_link_lops, prog);
3090         link->btp = btp;
3091
3092         err = bpf_link_prime(&link->link, &link_primer);
3093         if (err) {
3094                 kfree(link);
3095                 goto out_put_btp;
3096         }
3097
3098         err = bpf_probe_register(link->btp, prog);
3099         if (err) {
3100                 bpf_link_cleanup(&link_primer);
3101                 goto out_put_btp;
3102         }
3103
3104         return bpf_link_settle(&link_primer);
3105
3106 out_put_btp:
3107         bpf_put_raw_tracepoint(btp);
3108 out_put_prog:
3109         bpf_prog_put(prog);
3110         return err;
3111 }
3112
3113 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3114                                              enum bpf_attach_type attach_type)
3115 {
3116         switch (prog->type) {
3117         case BPF_PROG_TYPE_CGROUP_SOCK:
3118         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3119         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3120         case BPF_PROG_TYPE_SK_LOOKUP:
3121                 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3122         case BPF_PROG_TYPE_CGROUP_SKB:
3123                 if (!capable(CAP_NET_ADMIN))
3124                         /* cg-skb progs can be loaded by unpriv user.
3125                          * check permissions at attach time.
3126                          */
3127                         return -EPERM;
3128                 return prog->enforce_expected_attach_type &&
3129                         prog->expected_attach_type != attach_type ?
3130                         -EINVAL : 0;
3131         default:
3132                 return 0;
3133         }
3134 }
3135
3136 static enum bpf_prog_type
3137 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3138 {
3139         switch (attach_type) {
3140         case BPF_CGROUP_INET_INGRESS:
3141         case BPF_CGROUP_INET_EGRESS:
3142                 return BPF_PROG_TYPE_CGROUP_SKB;
3143         case BPF_CGROUP_INET_SOCK_CREATE:
3144         case BPF_CGROUP_INET_SOCK_RELEASE:
3145         case BPF_CGROUP_INET4_POST_BIND:
3146         case BPF_CGROUP_INET6_POST_BIND:
3147                 return BPF_PROG_TYPE_CGROUP_SOCK;
3148         case BPF_CGROUP_INET4_BIND:
3149         case BPF_CGROUP_INET6_BIND:
3150         case BPF_CGROUP_INET4_CONNECT:
3151         case BPF_CGROUP_INET6_CONNECT:
3152         case BPF_CGROUP_INET4_GETPEERNAME:
3153         case BPF_CGROUP_INET6_GETPEERNAME:
3154         case BPF_CGROUP_INET4_GETSOCKNAME:
3155         case BPF_CGROUP_INET6_GETSOCKNAME:
3156         case BPF_CGROUP_UDP4_SENDMSG:
3157         case BPF_CGROUP_UDP6_SENDMSG:
3158         case BPF_CGROUP_UDP4_RECVMSG:
3159         case BPF_CGROUP_UDP6_RECVMSG:
3160                 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3161         case BPF_CGROUP_SOCK_OPS:
3162                 return BPF_PROG_TYPE_SOCK_OPS;
3163         case BPF_CGROUP_DEVICE:
3164                 return BPF_PROG_TYPE_CGROUP_DEVICE;
3165         case BPF_SK_MSG_VERDICT:
3166                 return BPF_PROG_TYPE_SK_MSG;
3167         case BPF_SK_SKB_STREAM_PARSER:
3168         case BPF_SK_SKB_STREAM_VERDICT:
3169         case BPF_SK_SKB_VERDICT:
3170                 return BPF_PROG_TYPE_SK_SKB;
3171         case BPF_LIRC_MODE2:
3172                 return BPF_PROG_TYPE_LIRC_MODE2;
3173         case BPF_FLOW_DISSECTOR:
3174                 return BPF_PROG_TYPE_FLOW_DISSECTOR;
3175         case BPF_CGROUP_SYSCTL:
3176                 return BPF_PROG_TYPE_CGROUP_SYSCTL;
3177         case BPF_CGROUP_GETSOCKOPT:
3178         case BPF_CGROUP_SETSOCKOPT:
3179                 return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3180         case BPF_TRACE_ITER:
3181                 return BPF_PROG_TYPE_TRACING;
3182         case BPF_SK_LOOKUP:
3183                 return BPF_PROG_TYPE_SK_LOOKUP;
3184         case BPF_XDP:
3185                 return BPF_PROG_TYPE_XDP;
3186         default:
3187                 return BPF_PROG_TYPE_UNSPEC;
3188         }
3189 }
3190
3191 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3192
3193 #define BPF_F_ATTACH_MASK \
3194         (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3195
3196 static int bpf_prog_attach(const union bpf_attr *attr)
3197 {
3198         enum bpf_prog_type ptype;
3199         struct bpf_prog *prog;
3200         int ret;
3201
3202         if (CHECK_ATTR(BPF_PROG_ATTACH))
3203                 return -EINVAL;
3204
3205         if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3206                 return -EINVAL;
3207
3208         ptype = attach_type_to_prog_type(attr->attach_type);
3209         if (ptype == BPF_PROG_TYPE_UNSPEC)
3210                 return -EINVAL;
3211
3212         prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3213         if (IS_ERR(prog))
3214                 return PTR_ERR(prog);
3215
3216         if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3217                 bpf_prog_put(prog);
3218                 return -EINVAL;
3219         }
3220
3221         switch (ptype) {
3222         case BPF_PROG_TYPE_SK_SKB:
3223         case BPF_PROG_TYPE_SK_MSG:
3224                 ret = sock_map_get_from_fd(attr, prog);
3225                 break;
3226         case BPF_PROG_TYPE_LIRC_MODE2:
3227                 ret = lirc_prog_attach(attr, prog);
3228                 break;
3229         case BPF_PROG_TYPE_FLOW_DISSECTOR:
3230                 ret = netns_bpf_prog_attach(attr, prog);
3231                 break;
3232         case BPF_PROG_TYPE_CGROUP_DEVICE:
3233         case BPF_PROG_TYPE_CGROUP_SKB:
3234         case BPF_PROG_TYPE_CGROUP_SOCK:
3235         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3236         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3237         case BPF_PROG_TYPE_CGROUP_SYSCTL:
3238         case BPF_PROG_TYPE_SOCK_OPS:
3239                 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3240                 break;
3241         default:
3242                 ret = -EINVAL;
3243         }
3244
3245         if (ret)
3246                 bpf_prog_put(prog);
3247         return ret;
3248 }
3249
3250 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3251
3252 static int bpf_prog_detach(const union bpf_attr *attr)
3253 {
3254         enum bpf_prog_type ptype;
3255
3256         if (CHECK_ATTR(BPF_PROG_DETACH))
3257                 return -EINVAL;
3258
3259         ptype = attach_type_to_prog_type(attr->attach_type);
3260
3261         switch (ptype) {
3262         case BPF_PROG_TYPE_SK_MSG:
3263         case BPF_PROG_TYPE_SK_SKB:
3264                 return sock_map_prog_detach(attr, ptype);
3265         case BPF_PROG_TYPE_LIRC_MODE2:
3266                 return lirc_prog_detach(attr);
3267         case BPF_PROG_TYPE_FLOW_DISSECTOR:
3268                 return netns_bpf_prog_detach(attr, ptype);
3269         case BPF_PROG_TYPE_CGROUP_DEVICE:
3270         case BPF_PROG_TYPE_CGROUP_SKB:
3271         case BPF_PROG_TYPE_CGROUP_SOCK:
3272         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3273         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3274         case BPF_PROG_TYPE_CGROUP_SYSCTL:
3275         case BPF_PROG_TYPE_SOCK_OPS:
3276                 return cgroup_bpf_prog_detach(attr, ptype);
3277         default:
3278                 return -EINVAL;
3279         }
3280 }
3281
3282 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3283
3284 static int bpf_prog_query(const union bpf_attr *attr,
3285                           union bpf_attr __user *uattr)
3286 {
3287         if (!capable(CAP_NET_ADMIN))
3288                 return -EPERM;
3289         if (CHECK_ATTR(BPF_PROG_QUERY))
3290                 return -EINVAL;
3291         if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3292                 return -EINVAL;
3293
3294         switch (attr->query.attach_type) {
3295         case BPF_CGROUP_INET_INGRESS:
3296         case BPF_CGROUP_INET_EGRESS:
3297         case BPF_CGROUP_INET_SOCK_CREATE:
3298         case BPF_CGROUP_INET_SOCK_RELEASE:
3299         case BPF_CGROUP_INET4_BIND:
3300         case BPF_CGROUP_INET6_BIND:
3301         case BPF_CGROUP_INET4_POST_BIND:
3302         case BPF_CGROUP_INET6_POST_BIND:
3303         case BPF_CGROUP_INET4_CONNECT:
3304         case BPF_CGROUP_INET6_CONNECT:
3305         case BPF_CGROUP_INET4_GETPEERNAME:
3306         case BPF_CGROUP_INET6_GETPEERNAME:
3307         case BPF_CGROUP_INET4_GETSOCKNAME:
3308         case BPF_CGROUP_INET6_GETSOCKNAME:
3309         case BPF_CGROUP_UDP4_SENDMSG:
3310         case BPF_CGROUP_UDP6_SENDMSG:
3311         case BPF_CGROUP_UDP4_RECVMSG:
3312         case BPF_CGROUP_UDP6_RECVMSG:
3313         case BPF_CGROUP_SOCK_OPS:
3314         case BPF_CGROUP_DEVICE:
3315         case BPF_CGROUP_SYSCTL:
3316         case BPF_CGROUP_GETSOCKOPT:
3317         case BPF_CGROUP_SETSOCKOPT:
3318                 return cgroup_bpf_prog_query(attr, uattr);
3319         case BPF_LIRC_MODE2:
3320                 return lirc_prog_query(attr, uattr);
3321         case BPF_FLOW_DISSECTOR:
3322         case BPF_SK_LOOKUP:
3323                 return netns_bpf_prog_query(attr, uattr);
3324         default:
3325                 return -EINVAL;
3326         }
3327 }
3328
3329 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3330
3331 static int bpf_prog_test_run(const union bpf_attr *attr,
3332                              union bpf_attr __user *uattr)
3333 {
3334         struct bpf_prog *prog;
3335         int ret = -ENOTSUPP;
3336
3337         if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3338                 return -EINVAL;
3339
3340         if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3341             (!attr->test.ctx_size_in && attr->test.ctx_in))
3342                 return -EINVAL;
3343
3344         if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3345             (!attr->test.ctx_size_out && attr->test.ctx_out))
3346                 return -EINVAL;
3347
3348         prog = bpf_prog_get(attr->test.prog_fd);
3349         if (IS_ERR(prog))
3350                 return PTR_ERR(prog);
3351
3352         if (prog->aux->ops->test_run)
3353                 ret = prog->aux->ops->test_run(prog, attr, uattr);
3354
3355         bpf_prog_put(prog);
3356         return ret;
3357 }
3358
3359 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3360
3361 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3362                                union bpf_attr __user *uattr,
3363                                struct idr *idr,
3364                                spinlock_t *lock)
3365 {
3366         u32 next_id = attr->start_id;
3367         int err = 0;
3368
3369         if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3370                 return -EINVAL;
3371
3372         if (!capable(CAP_SYS_ADMIN))
3373                 return -EPERM;
3374
3375         next_id++;
3376         spin_lock_bh(lock);
3377         if (!idr_get_next(idr, &next_id))
3378                 err = -ENOENT;
3379         spin_unlock_bh(lock);
3380
3381         if (!err)
3382                 err = put_user(next_id, &uattr->next_id);
3383
3384         return err;
3385 }
3386
3387 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3388 {
3389         struct bpf_map *map;
3390
3391         spin_lock_bh(&map_idr_lock);
3392 again:
3393         map = idr_get_next(&map_idr, id);
3394         if (map) {
3395                 map = __bpf_map_inc_not_zero(map, false);
3396                 if (IS_ERR(map)) {
3397                         (*id)++;
3398                         goto again;
3399                 }
3400         }
3401         spin_unlock_bh(&map_idr_lock);
3402
3403         return map;
3404 }
3405
3406 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3407 {
3408         struct bpf_prog *prog;
3409
3410         spin_lock_bh(&prog_idr_lock);
3411 again:
3412         prog = idr_get_next(&prog_idr, id);
3413         if (prog) {
3414                 prog = bpf_prog_inc_not_zero(prog);
3415                 if (IS_ERR(prog)) {
3416                         (*id)++;
3417                         goto again;
3418                 }
3419         }
3420         spin_unlock_bh(&prog_idr_lock);
3421
3422         return prog;
3423 }
3424
3425 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3426
3427 struct bpf_prog *bpf_prog_by_id(u32 id)
3428 {
3429         struct bpf_prog *prog;
3430
3431         if (!id)
3432                 return ERR_PTR(-ENOENT);
3433
3434         spin_lock_bh(&prog_idr_lock);
3435         prog = idr_find(&prog_idr, id);
3436         if (prog)
3437                 prog = bpf_prog_inc_not_zero(prog);
3438         else
3439                 prog = ERR_PTR(-ENOENT);
3440         spin_unlock_bh(&prog_idr_lock);
3441         return prog;
3442 }
3443
3444 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3445 {
3446         struct bpf_prog *prog;
3447         u32 id = attr->prog_id;
3448         int fd;
3449
3450         if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3451                 return -EINVAL;
3452
3453         if (!capable(CAP_SYS_ADMIN))
3454                 return -EPERM;
3455
3456         prog = bpf_prog_by_id(id);
3457         if (IS_ERR(prog))
3458                 return PTR_ERR(prog);
3459
3460         fd = bpf_prog_new_fd(prog);
3461         if (fd < 0)
3462                 bpf_prog_put(prog);
3463
3464         return fd;
3465 }
3466
3467 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3468
3469 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3470 {
3471         struct bpf_map *map;
3472         u32 id = attr->map_id;
3473         int f_flags;
3474         int fd;
3475
3476         if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3477             attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3478                 return -EINVAL;
3479
3480         if (!capable(CAP_SYS_ADMIN))
3481                 return -EPERM;
3482
3483         f_flags = bpf_get_file_flag(attr->open_flags);
3484         if (f_flags < 0)
3485                 return f_flags;
3486
3487         spin_lock_bh(&map_idr_lock);
3488         map = idr_find(&map_idr, id);
3489         if (map)
3490                 map = __bpf_map_inc_not_zero(map, true);
3491         else
3492                 map = ERR_PTR(-ENOENT);
3493         spin_unlock_bh(&map_idr_lock);
3494
3495         if (IS_ERR(map))
3496                 return PTR_ERR(map);
3497
3498         fd = bpf_map_new_fd(map, f_flags);
3499         if (fd < 0)
3500                 bpf_map_put_with_uref(map);
3501
3502         return fd;
3503 }
3504
3505 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3506                                               unsigned long addr, u32 *off,
3507                                               u32 *type)
3508 {
3509         const struct bpf_map *map;
3510         int i;
3511
3512         mutex_lock(&prog->aux->used_maps_mutex);
3513         for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3514                 map = prog->aux->used_maps[i];
3515                 if (map == (void *)addr) {
3516                         *type = BPF_PSEUDO_MAP_FD;
3517                         goto out;
3518                 }
3519                 if (!map->ops->map_direct_value_meta)
3520                         continue;
3521                 if (!map->ops->map_direct_value_meta(map, addr, off)) {
3522                         *type = BPF_PSEUDO_MAP_VALUE;
3523                         goto out;
3524                 }
3525         }
3526         map = NULL;
3527
3528 out:
3529         mutex_unlock(&prog->aux->used_maps_mutex);
3530         return map;
3531 }
3532
3533 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3534                                               const struct cred *f_cred)
3535 {
3536         const struct bpf_map *map;
3537         struct bpf_insn *insns;
3538         u32 off, type;
3539         u64 imm;
3540         u8 code;
3541         int i;
3542
3543         insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3544                         GFP_USER);
3545         if (!insns)
3546                 return insns;
3547
3548         for (i = 0; i < prog->len; i++) {
3549                 code = insns[i].code;
3550
3551                 if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3552                         insns[i].code = BPF_JMP | BPF_CALL;
3553                         insns[i].imm = BPF_FUNC_tail_call;
3554                         /* fall-through */
3555                 }
3556                 if (code == (BPF_JMP | BPF_CALL) ||
3557                     code == (BPF_JMP | BPF_CALL_ARGS)) {
3558                         if (code == (BPF_JMP | BPF_CALL_ARGS))
3559                                 insns[i].code = BPF_JMP | BPF_CALL;
3560                         if (!bpf_dump_raw_ok(f_cred))
3561                                 insns[i].imm = 0;
3562                         continue;
3563                 }
3564                 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3565                         insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3566                         continue;
3567                 }
3568
3569                 if (code != (BPF_LD | BPF_IMM | BPF_DW))
3570                         continue;
3571
3572                 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3573                 map = bpf_map_from_imm(prog, imm, &off, &type);
3574                 if (map) {
3575                         insns[i].src_reg = type;
3576                         insns[i].imm = map->id;
3577                         insns[i + 1].imm = off;
3578                         continue;
3579                 }
3580         }
3581
3582         return insns;
3583 }
3584
3585 static int set_info_rec_size(struct bpf_prog_info *info)
3586 {
3587         /*
3588          * Ensure info.*_rec_size is the same as kernel expected size
3589          *
3590          * or
3591          *
3592          * Only allow zero *_rec_size if both _rec_size and _cnt are
3593          * zero.  In this case, the kernel will set the expected
3594          * _rec_size back to the info.
3595          */
3596
3597         if ((info->nr_func_info || info->func_info_rec_size) &&
3598             info->func_info_rec_size != sizeof(struct bpf_func_info))
3599                 return -EINVAL;
3600
3601         if ((info->nr_line_info || info->line_info_rec_size) &&
3602             info->line_info_rec_size != sizeof(struct bpf_line_info))
3603                 return -EINVAL;
3604
3605         if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3606             info->jited_line_info_rec_size != sizeof(__u64))
3607                 return -EINVAL;
3608
3609         info->func_info_rec_size = sizeof(struct bpf_func_info);
3610         info->line_info_rec_size = sizeof(struct bpf_line_info);
3611         info->jited_line_info_rec_size = sizeof(__u64);
3612
3613         return 0;
3614 }
3615
3616 static int bpf_prog_get_info_by_fd(struct file *file,
3617                                    struct bpf_prog *prog,
3618                                    const union bpf_attr *attr,
3619                                    union bpf_attr __user *uattr)
3620 {
3621         struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3622         struct bpf_prog_info info;
3623         u32 info_len = attr->info.info_len;
3624         struct bpf_prog_kstats stats;
3625         char __user *uinsns;
3626         u32 ulen;
3627         int err;
3628
3629         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3630         if (err)
3631                 return err;
3632         info_len = min_t(u32, sizeof(info), info_len);
3633
3634         memset(&info, 0, sizeof(info));
3635         if (copy_from_user(&info, uinfo, info_len))
3636                 return -EFAULT;
3637
3638         info.type = prog->type;
3639         info.id = prog->aux->id;
3640         info.load_time = prog->aux->load_time;
3641         info.created_by_uid = from_kuid_munged(current_user_ns(),
3642                                                prog->aux->user->uid);
3643         info.gpl_compatible = prog->gpl_compatible;
3644
3645         memcpy(info.tag, prog->tag, sizeof(prog->tag));
3646         memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3647
3648         mutex_lock(&prog->aux->used_maps_mutex);
3649         ulen = info.nr_map_ids;
3650         info.nr_map_ids = prog->aux->used_map_cnt;
3651         ulen = min_t(u32, info.nr_map_ids, ulen);
3652         if (ulen) {
3653                 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3654                 u32 i;
3655
3656                 for (i = 0; i < ulen; i++)
3657                         if (put_user(prog->aux->used_maps[i]->id,
3658                                      &user_map_ids[i])) {
3659                                 mutex_unlock(&prog->aux->used_maps_mutex);
3660                                 return -EFAULT;
3661                         }
3662         }
3663         mutex_unlock(&prog->aux->used_maps_mutex);
3664
3665         err = set_info_rec_size(&info);
3666         if (err)
3667                 return err;
3668
3669         bpf_prog_get_stats(prog, &stats);
3670         info.run_time_ns = stats.nsecs;
3671         info.run_cnt = stats.cnt;
3672         info.recursion_misses = stats.misses;
3673
3674         info.verified_insns = prog->aux->verified_insns;
3675
3676         if (!bpf_capable()) {
3677                 info.jited_prog_len = 0;
3678                 info.xlated_prog_len = 0;
3679                 info.nr_jited_ksyms = 0;
3680                 info.nr_jited_func_lens = 0;
3681                 info.nr_func_info = 0;
3682                 info.nr_line_info = 0;
3683                 info.nr_jited_line_info = 0;
3684                 goto done;
3685         }
3686
3687         ulen = info.xlated_prog_len;
3688         info.xlated_prog_len = bpf_prog_insn_size(prog);
3689         if (info.xlated_prog_len && ulen) {
3690                 struct bpf_insn *insns_sanitized;
3691                 bool fault;
3692
3693                 if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3694                         info.xlated_prog_insns = 0;
3695                         goto done;
3696                 }
3697                 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3698                 if (!insns_sanitized)
3699                         return -ENOMEM;
3700                 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3701                 ulen = min_t(u32, info.xlated_prog_len, ulen);
3702                 fault = copy_to_user(uinsns, insns_sanitized, ulen);
3703                 kfree(insns_sanitized);
3704                 if (fault)
3705                         return -EFAULT;
3706         }
3707
3708         if (bpf_prog_is_dev_bound(prog->aux)) {
3709                 err = bpf_prog_offload_info_fill(&info, prog);
3710                 if (err)
3711                         return err;
3712                 goto done;
3713         }
3714
3715         /* NOTE: the following code is supposed to be skipped for offload.
3716          * bpf_prog_offload_info_fill() is the place to fill similar fields
3717          * for offload.
3718          */
3719         ulen = info.jited_prog_len;
3720         if (prog->aux->func_cnt) {
3721                 u32 i;
3722
3723                 info.jited_prog_len = 0;
3724                 for (i = 0; i < prog->aux->func_cnt; i++)
3725                         info.jited_prog_len += prog->aux->func[i]->jited_len;
3726         } else {
3727                 info.jited_prog_len = prog->jited_len;
3728         }
3729
3730         if (info.jited_prog_len && ulen) {
3731                 if (bpf_dump_raw_ok(file->f_cred)) {
3732                         uinsns = u64_to_user_ptr(info.jited_prog_insns);
3733                         ulen = min_t(u32, info.jited_prog_len, ulen);
3734
3735                         /* for multi-function programs, copy the JITed
3736                          * instructions for all the functions
3737                          */
3738                         if (prog->aux->func_cnt) {
3739                                 u32 len, free, i;
3740                                 u8 *img;
3741
3742                                 free = ulen;
3743                                 for (i = 0; i < prog->aux->func_cnt; i++) {
3744                                         len = prog->aux->func[i]->jited_len;
3745                                         len = min_t(u32, len, free);
3746                                         img = (u8 *) prog->aux->func[i]->bpf_func;
3747                                         if (copy_to_user(uinsns, img, len))
3748                                                 return -EFAULT;
3749                                         uinsns += len;
3750                                         free -= len;
3751                                         if (!free)
3752                                                 break;
3753                                 }
3754                         } else {
3755                                 if (copy_to_user(uinsns, prog->bpf_func, ulen))
3756                                         return -EFAULT;
3757                         }
3758                 } else {
3759                         info.jited_prog_insns = 0;
3760                 }
3761         }
3762
3763         ulen = info.nr_jited_ksyms;
3764         info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3765         if (ulen) {
3766                 if (bpf_dump_raw_ok(file->f_cred)) {
3767                         unsigned long ksym_addr;
3768                         u64 __user *user_ksyms;
3769                         u32 i;
3770
3771                         /* copy the address of the kernel symbol
3772                          * corresponding to each function
3773                          */
3774                         ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3775                         user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3776                         if (prog->aux->func_cnt) {
3777                                 for (i = 0; i < ulen; i++) {
3778                                         ksym_addr = (unsigned long)
3779                                                 prog->aux->func[i]->bpf_func;
3780                                         if (put_user((u64) ksym_addr,
3781                                                      &user_ksyms[i]))
3782                                                 return -EFAULT;
3783                                 }
3784                         } else {
3785                                 ksym_addr = (unsigned long) prog->bpf_func;
3786                                 if (put_user((u64) ksym_addr, &user_ksyms[0]))
3787                                         return -EFAULT;
3788                         }
3789                 } else {
3790                         info.jited_ksyms = 0;
3791                 }
3792         }
3793
3794         ulen = info.nr_jited_func_lens;
3795         info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3796         if (ulen) {
3797                 if (bpf_dump_raw_ok(file->f_cred)) {
3798                         u32 __user *user_lens;
3799                         u32 func_len, i;
3800
3801                         /* copy the JITed image lengths for each function */
3802                         ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3803                         user_lens = u64_to_user_ptr(info.jited_func_lens);
3804                         if (prog->aux->func_cnt) {
3805                                 for (i = 0; i < ulen; i++) {
3806                                         func_len =
3807                                                 prog->aux->func[i]->jited_len;
3808                                         if (put_user(func_len, &user_lens[i]))
3809                                                 return -EFAULT;
3810                                 }
3811                         } else {
3812                                 func_len = prog->jited_len;
3813                                 if (put_user(func_len, &user_lens[0]))
3814                                         return -EFAULT;
3815                         }
3816                 } else {
3817                         info.jited_func_lens = 0;
3818                 }
3819         }
3820
3821         if (prog->aux->btf)
3822                 info.btf_id = btf_obj_id(prog->aux->btf);
3823
3824         ulen = info.nr_func_info;
3825         info.nr_func_info = prog->aux->func_info_cnt;
3826         if (info.nr_func_info && ulen) {
3827                 char __user *user_finfo;
3828
3829                 user_finfo = u64_to_user_ptr(info.func_info);
3830                 ulen = min_t(u32, info.nr_func_info, ulen);
3831                 if (copy_to_user(user_finfo, prog->aux->func_info,
3832                                  info.func_info_rec_size * ulen))
3833                         return -EFAULT;
3834         }
3835
3836         ulen = info.nr_line_info;
3837         info.nr_line_info = prog->aux->nr_linfo;
3838         if (info.nr_line_info && ulen) {
3839                 __u8 __user *user_linfo;
3840
3841                 user_linfo = u64_to_user_ptr(info.line_info);
3842                 ulen = min_t(u32, info.nr_line_info, ulen);
3843                 if (copy_to_user(user_linfo, prog->aux->linfo,
3844                                  info.line_info_rec_size * ulen))
3845                         return -EFAULT;
3846         }
3847
3848         ulen = info.nr_jited_line_info;
3849         if (prog->aux->jited_linfo)
3850                 info.nr_jited_line_info = prog->aux->nr_linfo;
3851         else
3852                 info.nr_jited_line_info = 0;
3853         if (info.nr_jited_line_info && ulen) {
3854                 if (bpf_dump_raw_ok(file->f_cred)) {
3855                         __u64 __user *user_linfo;
3856                         u32 i;
3857
3858                         user_linfo = u64_to_user_ptr(info.jited_line_info);
3859                         ulen = min_t(u32, info.nr_jited_line_info, ulen);
3860                         for (i = 0; i < ulen; i++) {
3861                                 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3862                                              &user_linfo[i]))
3863                                         return -EFAULT;
3864                         }
3865                 } else {
3866                         info.jited_line_info = 0;
3867                 }
3868         }
3869
3870         ulen = info.nr_prog_tags;
3871         info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3872         if (ulen) {
3873                 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3874                 u32 i;
3875
3876                 user_prog_tags = u64_to_user_ptr(info.prog_tags);
3877                 ulen = min_t(u32, info.nr_prog_tags, ulen);
3878                 if (prog->aux->func_cnt) {
3879                         for (i = 0; i < ulen; i++) {
3880                                 if (copy_to_user(user_prog_tags[i],
3881                                                  prog->aux->func[i]->tag,
3882                                                  BPF_TAG_SIZE))
3883                                         return -EFAULT;
3884                         }
3885                 } else {
3886                         if (copy_to_user(user_prog_tags[0],
3887                                          prog->tag, BPF_TAG_SIZE))
3888                                 return -EFAULT;
3889                 }
3890         }
3891
3892 done:
3893         if (copy_to_user(uinfo, &info, info_len) ||
3894             put_user(info_len, &uattr->info.info_len))
3895                 return -EFAULT;
3896
3897         return 0;
3898 }
3899
3900 static int bpf_map_get_info_by_fd(struct file *file,
3901                                   struct bpf_map *map,
3902                                   const union bpf_attr *attr,
3903                                   union bpf_attr __user *uattr)
3904 {
3905         struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3906         struct bpf_map_info info;
3907         u32 info_len = attr->info.info_len;
3908         int err;
3909
3910         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3911         if (err)
3912                 return err;
3913         info_len = min_t(u32, sizeof(info), info_len);
3914
3915         memset(&info, 0, sizeof(info));
3916         info.type = map->map_type;
3917         info.id = map->id;
3918         info.key_size = map->key_size;
3919         info.value_size = map->value_size;
3920         info.max_entries = map->max_entries;
3921         info.map_flags = map->map_flags;
3922         info.map_extra = map->map_extra;
3923         memcpy(info.name, map->name, sizeof(map->name));
3924
3925         if (map->btf) {
3926                 info.btf_id = btf_obj_id(map->btf);
3927                 info.btf_key_type_id = map->btf_key_type_id;
3928                 info.btf_value_type_id = map->btf_value_type_id;
3929         }
3930         info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3931
3932         if (bpf_map_is_dev_bound(map)) {
3933                 err = bpf_map_offload_info_fill(&info, map);
3934                 if (err)
3935                         return err;
3936         }
3937
3938         if (copy_to_user(uinfo, &info, info_len) ||
3939             put_user(info_len, &uattr->info.info_len))
3940                 return -EFAULT;
3941
3942         return 0;
3943 }
3944
3945 static int bpf_btf_get_info_by_fd(struct file *file,
3946                                   struct btf *btf,
3947                                   const union bpf_attr *attr,
3948                                   union bpf_attr __user *uattr)
3949 {
3950         struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3951         u32 info_len = attr->info.info_len;
3952         int err;
3953
3954         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3955         if (err)
3956                 return err;
3957
3958         return btf_get_info_by_fd(btf, attr, uattr);
3959 }
3960
3961 static int bpf_link_get_info_by_fd(struct file *file,
3962                                   struct bpf_link *link,
3963                                   const union bpf_attr *attr,
3964                                   union bpf_attr __user *uattr)
3965 {
3966         struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3967         struct bpf_link_info info;
3968         u32 info_len = attr->info.info_len;
3969         int err;
3970
3971         err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3972         if (err)
3973                 return err;
3974         info_len = min_t(u32, sizeof(info), info_len);
3975
3976         memset(&info, 0, sizeof(info));
3977         if (copy_from_user(&info, uinfo, info_len))
3978                 return -EFAULT;
3979
3980         info.type = link->type;
3981         info.id = link->id;
3982         info.prog_id = link->prog->aux->id;
3983
3984         if (link->ops->fill_link_info) {
3985                 err = link->ops->fill_link_info(link, &info);
3986                 if (err)
3987                         return err;
3988         }
3989
3990         if (copy_to_user(uinfo, &info, info_len) ||
3991             put_user(info_len, &uattr->info.info_len))
3992                 return -EFAULT;
3993
3994         return 0;
3995 }
3996
3997
3998 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3999
4000 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
4001                                   union bpf_attr __user *uattr)
4002 {
4003         int ufd = attr->info.bpf_fd;
4004         struct fd f;
4005         int err;
4006
4007         if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
4008                 return -EINVAL;
4009
4010         f = fdget(ufd);
4011         if (!f.file)
4012                 return -EBADFD;
4013
4014         if (f.file->f_op == &bpf_prog_fops)
4015                 err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
4016                                               uattr);
4017         else if (f.file->f_op == &bpf_map_fops)
4018                 err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4019                                              uattr);
4020         else if (f.file->f_op == &btf_fops)
4021                 err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4022         else if (f.file->f_op == &bpf_link_fops)
4023                 err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4024                                               attr, uattr);
4025         else
4026                 err = -EINVAL;
4027
4028         fdput(f);
4029         return err;
4030 }
4031
4032 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4033
4034 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4035 {
4036         if (CHECK_ATTR(BPF_BTF_LOAD))
4037                 return -EINVAL;
4038
4039         if (!bpf_capable())
4040                 return -EPERM;
4041
4042         return btf_new_fd(attr, uattr);
4043 }
4044
4045 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4046
4047 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4048 {
4049         if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4050                 return -EINVAL;
4051
4052         if (!capable(CAP_SYS_ADMIN))
4053                 return -EPERM;
4054
4055         return btf_get_fd_by_id(attr->btf_id);
4056 }
4057
4058 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4059                                     union bpf_attr __user *uattr,
4060                                     u32 prog_id, u32 fd_type,
4061                                     const char *buf, u64 probe_offset,
4062                                     u64 probe_addr)
4063 {
4064         char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4065         u32 len = buf ? strlen(buf) : 0, input_len;
4066         int err = 0;
4067
4068         if (put_user(len, &uattr->task_fd_query.buf_len))
4069                 return -EFAULT;
4070         input_len = attr->task_fd_query.buf_len;
4071         if (input_len && ubuf) {
4072                 if (!len) {
4073                         /* nothing to copy, just make ubuf NULL terminated */
4074                         char zero = '\0';
4075
4076                         if (put_user(zero, ubuf))
4077                                 return -EFAULT;
4078                 } else if (input_len >= len + 1) {
4079                         /* ubuf can hold the string with NULL terminator */
4080                         if (copy_to_user(ubuf, buf, len + 1))
4081                                 return -EFAULT;
4082                 } else {
4083                         /* ubuf cannot hold the string with NULL terminator,
4084                          * do a partial copy with NULL terminator.
4085                          */
4086                         char zero = '\0';
4087
4088                         err = -ENOSPC;
4089                         if (copy_to_user(ubuf, buf, input_len - 1))
4090                                 return -EFAULT;
4091                         if (put_user(zero, ubuf + input_len - 1))
4092                                 return -EFAULT;
4093                 }
4094         }
4095
4096         if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4097             put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4098             put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4099             put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4100                 return -EFAULT;
4101
4102         return err;
4103 }
4104
4105 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4106
4107 static int bpf_task_fd_query(const union bpf_attr *attr,
4108                              union bpf_attr __user *uattr)
4109 {
4110         pid_t pid = attr->task_fd_query.pid;
4111         u32 fd = attr->task_fd_query.fd;
4112         const struct perf_event *event;
4113         struct task_struct *task;
4114         struct file *file;
4115         int err;
4116
4117         if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4118                 return -EINVAL;
4119
4120         if (!capable(CAP_SYS_ADMIN))
4121                 return -EPERM;
4122
4123         if (attr->task_fd_query.flags != 0)
4124                 return -EINVAL;
4125
4126         task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4127         if (!task)
4128                 return -ENOENT;
4129
4130         err = 0;
4131         file = fget_task(task, fd);
4132         put_task_struct(task);
4133         if (!file)
4134                 return -EBADF;
4135
4136         if (file->f_op == &bpf_link_fops) {
4137                 struct bpf_link *link = file->private_data;
4138
4139                 if (link->ops == &bpf_raw_tp_link_lops) {
4140                         struct bpf_raw_tp_link *raw_tp =
4141                                 container_of(link, struct bpf_raw_tp_link, link);
4142                         struct bpf_raw_event_map *btp = raw_tp->btp;
4143
4144                         err = bpf_task_fd_query_copy(attr, uattr,
4145                                                      raw_tp->link.prog->aux->id,
4146                                                      BPF_FD_TYPE_RAW_TRACEPOINT,
4147                                                      btp->tp->name, 0, 0);
4148                         goto put_file;
4149                 }
4150                 goto out_not_supp;
4151         }
4152
4153         event = perf_get_event(file);
4154         if (!IS_ERR(event)) {
4155                 u64 probe_offset, probe_addr;
4156                 u32 prog_id, fd_type;
4157                 const char *buf;
4158
4159                 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4160                                               &buf, &probe_offset,
4161                                               &probe_addr);
4162                 if (!err)
4163                         err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4164                                                      fd_type, buf,
4165                                                      probe_offset,
4166                                                      probe_addr);
4167                 goto put_file;
4168         }
4169
4170 out_not_supp:
4171         err = -ENOTSUPP;
4172 put_file:
4173         fput(file);
4174         return err;
4175 }
4176
4177 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4178
4179 #define BPF_DO_BATCH(fn)                        \
4180         do {                                    \
4181                 if (!fn) {                      \
4182                         err = -ENOTSUPP;        \
4183                         goto err_put;           \
4184                 }                               \
4185                 err = fn(map, attr, uattr);     \
4186         } while (0)
4187
4188 static int bpf_map_do_batch(const union bpf_attr *attr,
4189                             union bpf_attr __user *uattr,
4190                             int cmd)
4191 {
4192         bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
4193                          cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
4194         bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
4195         struct bpf_map *map;
4196         int err, ufd;
4197         struct fd f;
4198
4199         if (CHECK_ATTR(BPF_MAP_BATCH))
4200                 return -EINVAL;
4201
4202         ufd = attr->batch.map_fd;
4203         f = fdget(ufd);
4204         map = __bpf_map_get(f);
4205         if (IS_ERR(map))
4206                 return PTR_ERR(map);
4207         if (has_write)
4208                 bpf_map_write_active_inc(map);
4209         if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4210                 err = -EPERM;
4211                 goto err_put;
4212         }
4213         if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4214                 err = -EPERM;
4215                 goto err_put;
4216         }
4217
4218         if (cmd == BPF_MAP_LOOKUP_BATCH)
4219                 BPF_DO_BATCH(map->ops->map_lookup_batch);
4220         else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4221                 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4222         else if (cmd == BPF_MAP_UPDATE_BATCH)
4223                 BPF_DO_BATCH(map->ops->map_update_batch);
4224         else
4225                 BPF_DO_BATCH(map->ops->map_delete_batch);
4226 err_put:
4227         if (has_write)
4228                 bpf_map_write_active_dec(map);
4229         fdput(f);
4230         return err;
4231 }
4232
4233 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4234                                    struct bpf_prog *prog)
4235 {
4236         if (attr->link_create.attach_type != prog->expected_attach_type)
4237                 return -EINVAL;
4238
4239         if (prog->expected_attach_type == BPF_TRACE_ITER)
4240                 return bpf_iter_link_attach(attr, uattr, prog);
4241         else if (prog->type == BPF_PROG_TYPE_EXT)
4242                 return bpf_tracing_prog_attach(prog,
4243                                                attr->link_create.target_fd,
4244                                                attr->link_create.target_btf_id);
4245         return -EINVAL;
4246 }
4247
4248 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4249 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4250 {
4251         enum bpf_prog_type ptype;
4252         struct bpf_prog *prog;
4253         int ret;
4254
4255         if (CHECK_ATTR(BPF_LINK_CREATE))
4256                 return -EINVAL;
4257
4258         prog = bpf_prog_get(attr->link_create.prog_fd);
4259         if (IS_ERR(prog))
4260                 return PTR_ERR(prog);
4261
4262         ret = bpf_prog_attach_check_attach_type(prog,
4263                                                 attr->link_create.attach_type);
4264         if (ret)
4265                 goto out;
4266
4267         switch (prog->type) {
4268         case BPF_PROG_TYPE_EXT:
4269                 ret = tracing_bpf_link_attach(attr, uattr, prog);
4270                 goto out;
4271         case BPF_PROG_TYPE_PERF_EVENT:
4272         case BPF_PROG_TYPE_KPROBE:
4273         case BPF_PROG_TYPE_TRACEPOINT:
4274                 if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4275                         ret = -EINVAL;
4276                         goto out;
4277                 }
4278                 ptype = prog->type;
4279                 break;
4280         default:
4281                 ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4282                 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4283                         ret = -EINVAL;
4284                         goto out;
4285                 }
4286                 break;
4287         }
4288
4289         switch (ptype) {
4290         case BPF_PROG_TYPE_CGROUP_SKB:
4291         case BPF_PROG_TYPE_CGROUP_SOCK:
4292         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4293         case BPF_PROG_TYPE_SOCK_OPS:
4294         case BPF_PROG_TYPE_CGROUP_DEVICE:
4295         case BPF_PROG_TYPE_CGROUP_SYSCTL:
4296         case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4297                 ret = cgroup_bpf_link_attach(attr, prog);
4298                 break;
4299         case BPF_PROG_TYPE_TRACING:
4300                 ret = tracing_bpf_link_attach(attr, uattr, prog);
4301                 break;
4302         case BPF_PROG_TYPE_FLOW_DISSECTOR:
4303         case BPF_PROG_TYPE_SK_LOOKUP:
4304                 ret = netns_bpf_link_create(attr, prog);
4305                 break;
4306 #ifdef CONFIG_NET
4307         case BPF_PROG_TYPE_XDP:
4308                 ret = bpf_xdp_link_attach(attr, prog);
4309                 break;
4310 #endif
4311 #ifdef CONFIG_PERF_EVENTS
4312         case BPF_PROG_TYPE_PERF_EVENT:
4313         case BPF_PROG_TYPE_TRACEPOINT:
4314         case BPF_PROG_TYPE_KPROBE:
4315                 ret = bpf_perf_link_attach(attr, prog);
4316                 break;
4317 #endif
4318         default:
4319                 ret = -EINVAL;
4320         }
4321
4322 out:
4323         if (ret < 0)
4324                 bpf_prog_put(prog);
4325         return ret;
4326 }
4327
4328 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4329
4330 static int link_update(union bpf_attr *attr)
4331 {
4332         struct bpf_prog *old_prog = NULL, *new_prog;
4333         struct bpf_link *link;
4334         u32 flags;
4335         int ret;
4336
4337         if (CHECK_ATTR(BPF_LINK_UPDATE))
4338                 return -EINVAL;
4339
4340         flags = attr->link_update.flags;
4341         if (flags & ~BPF_F_REPLACE)
4342                 return -EINVAL;
4343
4344         link = bpf_link_get_from_fd(attr->link_update.link_fd);
4345         if (IS_ERR(link))
4346                 return PTR_ERR(link);
4347
4348         new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4349         if (IS_ERR(new_prog)) {
4350                 ret = PTR_ERR(new_prog);
4351                 goto out_put_link;
4352         }
4353
4354         if (flags & BPF_F_REPLACE) {
4355                 old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4356                 if (IS_ERR(old_prog)) {
4357                         ret = PTR_ERR(old_prog);
4358                         old_prog = NULL;
4359                         goto out_put_progs;
4360                 }
4361         } else if (attr->link_update.old_prog_fd) {
4362                 ret = -EINVAL;
4363                 goto out_put_progs;
4364         }
4365
4366         if (link->ops->update_prog)
4367                 ret = link->ops->update_prog(link, new_prog, old_prog);
4368         else
4369                 ret = -EINVAL;
4370
4371 out_put_progs:
4372         if (old_prog)
4373                 bpf_prog_put(old_prog);
4374         if (ret)
4375                 bpf_prog_put(new_prog);
4376 out_put_link:
4377         bpf_link_put(link);
4378         return ret;
4379 }
4380
4381 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4382
4383 static int link_detach(union bpf_attr *attr)
4384 {
4385         struct bpf_link *link;
4386         int ret;
4387
4388         if (CHECK_ATTR(BPF_LINK_DETACH))
4389                 return -EINVAL;
4390
4391         link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4392         if (IS_ERR(link))
4393                 return PTR_ERR(link);
4394
4395         if (link->ops->detach)
4396                 ret = link->ops->detach(link);
4397         else
4398                 ret = -EOPNOTSUPP;
4399
4400         bpf_link_put(link);
4401         return ret;
4402 }
4403
4404 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4405 {
4406         return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4407 }
4408
4409 struct bpf_link *bpf_link_by_id(u32 id)
4410 {
4411         struct bpf_link *link;
4412
4413         if (!id)
4414                 return ERR_PTR(-ENOENT);
4415
4416         spin_lock_bh(&link_idr_lock);
4417         /* before link is "settled", ID is 0, pretend it doesn't exist yet */
4418         link = idr_find(&link_idr, id);
4419         if (link) {
4420                 if (link->id)
4421                         link = bpf_link_inc_not_zero(link);
4422                 else
4423                         link = ERR_PTR(-EAGAIN);
4424         } else {
4425                 link = ERR_PTR(-ENOENT);
4426         }
4427         spin_unlock_bh(&link_idr_lock);
4428         return link;
4429 }
4430
4431 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4432
4433 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4434 {
4435         struct bpf_link *link;
4436         u32 id = attr->link_id;
4437         int fd;
4438
4439         if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4440                 return -EINVAL;
4441
4442         if (!capable(CAP_SYS_ADMIN))
4443                 return -EPERM;
4444
4445         link = bpf_link_by_id(id);
4446         if (IS_ERR(link))
4447                 return PTR_ERR(link);
4448
4449         fd = bpf_link_new_fd(link);
4450         if (fd < 0)
4451                 bpf_link_put(link);
4452
4453         return fd;
4454 }
4455
4456 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4457
4458 static int bpf_stats_release(struct inode *inode, struct file *file)
4459 {
4460         mutex_lock(&bpf_stats_enabled_mutex);
4461         static_key_slow_dec(&bpf_stats_enabled_key.key);
4462         mutex_unlock(&bpf_stats_enabled_mutex);
4463         return 0;
4464 }
4465
4466 static const struct file_operations bpf_stats_fops = {
4467         .release = bpf_stats_release,
4468 };
4469
4470 static int bpf_enable_runtime_stats(void)
4471 {
4472         int fd;
4473
4474         mutex_lock(&bpf_stats_enabled_mutex);
4475
4476         /* Set a very high limit to avoid overflow */
4477         if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4478                 mutex_unlock(&bpf_stats_enabled_mutex);
4479                 return -EBUSY;
4480         }
4481
4482         fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4483         if (fd >= 0)
4484                 static_key_slow_inc(&bpf_stats_enabled_key.key);
4485
4486         mutex_unlock(&bpf_stats_enabled_mutex);
4487         return fd;
4488 }
4489
4490 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4491
4492 static int bpf_enable_stats(union bpf_attr *attr)
4493 {
4494
4495         if (CHECK_ATTR(BPF_ENABLE_STATS))
4496                 return -EINVAL;
4497
4498         if (!capable(CAP_SYS_ADMIN))
4499                 return -EPERM;
4500
4501         switch (attr->enable_stats.type) {
4502         case BPF_STATS_RUN_TIME:
4503                 return bpf_enable_runtime_stats();
4504         default:
4505                 break;
4506         }
4507         return -EINVAL;
4508 }
4509
4510 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4511
4512 static int bpf_iter_create(union bpf_attr *attr)
4513 {
4514         struct bpf_link *link;
4515         int err;
4516
4517         if (CHECK_ATTR(BPF_ITER_CREATE))
4518                 return -EINVAL;
4519
4520         if (attr->iter_create.flags)
4521                 return -EINVAL;
4522
4523         link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4524         if (IS_ERR(link))
4525                 return PTR_ERR(link);
4526
4527         err = bpf_iter_new_fd(link);
4528         bpf_link_put(link);
4529
4530         return err;
4531 }
4532
4533 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4534
4535 static int bpf_prog_bind_map(union bpf_attr *attr)
4536 {
4537         struct bpf_prog *prog;
4538         struct bpf_map *map;
4539         struct bpf_map **used_maps_old, **used_maps_new;
4540         int i, ret = 0;
4541
4542         if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4543                 return -EINVAL;
4544
4545         if (attr->prog_bind_map.flags)
4546                 return -EINVAL;
4547
4548         prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4549         if (IS_ERR(prog))
4550                 return PTR_ERR(prog);
4551
4552         map = bpf_map_get(attr->prog_bind_map.map_fd);
4553         if (IS_ERR(map)) {
4554                 ret = PTR_ERR(map);
4555                 goto out_prog_put;
4556         }
4557
4558         mutex_lock(&prog->aux->used_maps_mutex);
4559
4560         used_maps_old = prog->aux->used_maps;
4561
4562         for (i = 0; i < prog->aux->used_map_cnt; i++)
4563                 if (used_maps_old[i] == map) {
4564                         bpf_map_put(map);
4565                         goto out_unlock;
4566                 }
4567
4568         used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4569                                       sizeof(used_maps_new[0]),
4570                                       GFP_KERNEL);
4571         if (!used_maps_new) {
4572                 ret = -ENOMEM;
4573                 goto out_unlock;
4574         }
4575
4576         memcpy(used_maps_new, used_maps_old,
4577                sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4578         used_maps_new[prog->aux->used_map_cnt] = map;
4579
4580         prog->aux->used_map_cnt++;
4581         prog->aux->used_maps = used_maps_new;
4582
4583         kfree(used_maps_old);
4584
4585 out_unlock:
4586         mutex_unlock(&prog->aux->used_maps_mutex);
4587
4588         if (ret)
4589                 bpf_map_put(map);
4590 out_prog_put:
4591         bpf_prog_put(prog);
4592         return ret;
4593 }
4594
4595 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4596 {
4597         union bpf_attr attr;
4598         int err;
4599
4600         if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4601                 return -EPERM;
4602
4603         err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4604         if (err)
4605                 return err;
4606         size = min_t(u32, size, sizeof(attr));
4607
4608         /* copy attributes from user space, may be less than sizeof(bpf_attr) */
4609         memset(&attr, 0, sizeof(attr));
4610         if (copy_from_bpfptr(&attr, uattr, size) != 0)
4611                 return -EFAULT;
4612
4613         err = security_bpf(cmd, &attr, size);
4614         if (err < 0)
4615                 return err;
4616
4617         switch (cmd) {
4618         case BPF_MAP_CREATE:
4619                 err = map_create(&attr);
4620                 break;
4621         case BPF_MAP_LOOKUP_ELEM:
4622                 err = map_lookup_elem(&attr);
4623                 break;
4624         case BPF_MAP_UPDATE_ELEM:
4625                 err = map_update_elem(&attr, uattr);
4626                 break;
4627         case BPF_MAP_DELETE_ELEM:
4628                 err = map_delete_elem(&attr);
4629                 break;
4630         case BPF_MAP_GET_NEXT_KEY:
4631                 err = map_get_next_key(&attr);
4632                 break;
4633         case BPF_MAP_FREEZE:
4634                 err = map_freeze(&attr);
4635                 break;
4636         case BPF_PROG_LOAD:
4637                 err = bpf_prog_load(&attr, uattr);
4638                 break;
4639         case BPF_OBJ_PIN:
4640                 err = bpf_obj_pin(&attr);
4641                 break;
4642         case BPF_OBJ_GET:
4643                 err = bpf_obj_get(&attr);
4644                 break;
4645         case BPF_PROG_ATTACH:
4646                 err = bpf_prog_attach(&attr);
4647                 break;
4648         case BPF_PROG_DETACH:
4649                 err = bpf_prog_detach(&attr);
4650                 break;
4651         case BPF_PROG_QUERY:
4652                 err = bpf_prog_query(&attr, uattr.user);
4653                 break;
4654         case BPF_PROG_TEST_RUN:
4655                 err = bpf_prog_test_run(&attr, uattr.user);
4656                 break;
4657         case BPF_PROG_GET_NEXT_ID:
4658                 err = bpf_obj_get_next_id(&attr, uattr.user,
4659                                           &prog_idr, &prog_idr_lock);
4660                 break;
4661         case BPF_MAP_GET_NEXT_ID:
4662                 err = bpf_obj_get_next_id(&attr, uattr.user,
4663                                           &map_idr, &map_idr_lock);
4664                 break;
4665         case BPF_BTF_GET_NEXT_ID:
4666                 err = bpf_obj_get_next_id(&attr, uattr.user,
4667                                           &btf_idr, &btf_idr_lock);
4668                 break;
4669         case BPF_PROG_GET_FD_BY_ID:
4670                 err = bpf_prog_get_fd_by_id(&attr);
4671                 break;
4672         case BPF_MAP_GET_FD_BY_ID:
4673                 err = bpf_map_get_fd_by_id(&attr);
4674                 break;
4675         case BPF_OBJ_GET_INFO_BY_FD:
4676                 err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4677                 break;
4678         case BPF_RAW_TRACEPOINT_OPEN:
4679                 err = bpf_raw_tracepoint_open(&attr);
4680                 break;
4681         case BPF_BTF_LOAD:
4682                 err = bpf_btf_load(&attr, uattr);
4683                 break;
4684         case BPF_BTF_GET_FD_BY_ID:
4685                 err = bpf_btf_get_fd_by_id(&attr);
4686                 break;
4687         case BPF_TASK_FD_QUERY:
4688                 err = bpf_task_fd_query(&attr, uattr.user);
4689                 break;
4690         case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4691                 err = map_lookup_and_delete_elem(&attr);
4692                 break;
4693         case BPF_MAP_LOOKUP_BATCH:
4694                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4695                 break;
4696         case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4697                 err = bpf_map_do_batch(&attr, uattr.user,
4698                                        BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4699                 break;
4700         case BPF_MAP_UPDATE_BATCH:
4701                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4702                 break;
4703         case BPF_MAP_DELETE_BATCH:
4704                 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4705                 break;
4706         case BPF_LINK_CREATE:
4707                 err = link_create(&attr, uattr);
4708                 break;
4709         case BPF_LINK_UPDATE:
4710                 err = link_update(&attr);
4711                 break;
4712         case BPF_LINK_GET_FD_BY_ID:
4713                 err = bpf_link_get_fd_by_id(&attr);
4714                 break;
4715         case BPF_LINK_GET_NEXT_ID:
4716                 err = bpf_obj_get_next_id(&attr, uattr.user,
4717                                           &link_idr, &link_idr_lock);
4718                 break;
4719         case BPF_ENABLE_STATS:
4720                 err = bpf_enable_stats(&attr);
4721                 break;
4722         case BPF_ITER_CREATE:
4723                 err = bpf_iter_create(&attr);
4724                 break;
4725         case BPF_LINK_DETACH:
4726                 err = link_detach(&attr);
4727                 break;
4728         case BPF_PROG_BIND_MAP:
4729                 err = bpf_prog_bind_map(&attr);
4730                 break;
4731         default:
4732                 err = -EINVAL;
4733                 break;
4734         }
4735
4736         return err;
4737 }
4738
4739 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4740 {
4741         return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4742 }
4743
4744 static bool syscall_prog_is_valid_access(int off, int size,
4745                                          enum bpf_access_type type,
4746                                          const struct bpf_prog *prog,
4747                                          struct bpf_insn_access_aux *info)
4748 {
4749         if (off < 0 || off >= U16_MAX)
4750                 return false;
4751         if (off % size != 0)
4752                 return false;
4753         return true;
4754 }
4755
4756 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4757 {
4758         switch (cmd) {
4759         case BPF_MAP_CREATE:
4760         case BPF_MAP_UPDATE_ELEM:
4761         case BPF_MAP_FREEZE:
4762         case BPF_PROG_LOAD:
4763         case BPF_BTF_LOAD:
4764                 break;
4765         /* case BPF_PROG_TEST_RUN:
4766          * is not part of this list to prevent recursive test_run
4767          */
4768         default:
4769                 return -EINVAL;
4770         }
4771         return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4772 }
4773
4774 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4775         .func           = bpf_sys_bpf,
4776         .gpl_only       = false,
4777         .ret_type       = RET_INTEGER,
4778         .arg1_type      = ARG_ANYTHING,
4779         .arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
4780         .arg3_type      = ARG_CONST_SIZE,
4781 };
4782
4783 const struct bpf_func_proto * __weak
4784 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4785 {
4786         return bpf_base_func_proto(func_id);
4787 }
4788
4789 BPF_CALL_1(bpf_sys_close, u32, fd)
4790 {
4791         /* When bpf program calls this helper there should not be
4792          * an fdget() without matching completed fdput().
4793          * This helper is allowed in the following callchain only:
4794          * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4795          */
4796         return close_fd(fd);
4797 }
4798
4799 static const struct bpf_func_proto bpf_sys_close_proto = {
4800         .func           = bpf_sys_close,
4801         .gpl_only       = false,
4802         .ret_type       = RET_INTEGER,
4803         .arg1_type      = ARG_ANYTHING,
4804 };
4805
4806 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
4807 {
4808         if (flags)
4809                 return -EINVAL;
4810
4811         if (name_sz <= 1 || name[name_sz - 1])
4812                 return -EINVAL;
4813
4814         if (!bpf_dump_raw_ok(current_cred()))
4815                 return -EPERM;
4816
4817         *res = kallsyms_lookup_name(name);
4818         return *res ? 0 : -ENOENT;
4819 }
4820
4821 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
4822         .func           = bpf_kallsyms_lookup_name,
4823         .gpl_only       = false,
4824         .ret_type       = RET_INTEGER,
4825         .arg1_type      = ARG_PTR_TO_MEM,
4826         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
4827         .arg3_type      = ARG_ANYTHING,
4828         .arg4_type      = ARG_PTR_TO_LONG,
4829 };
4830
4831 static const struct bpf_func_proto *
4832 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4833 {
4834         switch (func_id) {
4835         case BPF_FUNC_sys_bpf:
4836                 return &bpf_sys_bpf_proto;
4837         case BPF_FUNC_btf_find_by_name_kind:
4838                 return &bpf_btf_find_by_name_kind_proto;
4839         case BPF_FUNC_sys_close:
4840                 return &bpf_sys_close_proto;
4841         case BPF_FUNC_kallsyms_lookup_name:
4842                 return &bpf_kallsyms_lookup_name_proto;
4843         default:
4844                 return tracing_prog_func_proto(func_id, prog);
4845         }
4846 }
4847
4848 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4849         .get_func_proto  = syscall_prog_func_proto,
4850         .is_valid_access = syscall_prog_is_valid_access,
4851 };
4852
4853 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4854         .test_run = bpf_prog_test_run_syscall,
4855 };