kernel/bpf/syscall.c

   1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of version 2 of the GNU General Public
   5  * License as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful, but
   8  * WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10  * General Public License for more details.
  11  */
  12 #include <linux/bpf.h>
  13 #include <linux/bpf_trace.h>
  14 #include <linux/bpf_lirc.h>
  15 #include <linux/btf.h>
  16 #include <linux/syscalls.h>
  17 #include <linux/slab.h>
  18 #include <linux/sched/signal.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/mmzone.h>
  21 #include <linux/anon_inodes.h>
  22 #include <linux/fdtable.h>
  23 #include <linux/file.h>
  24 #include <linux/fs.h>
  25 #include <linux/license.h>
  26 #include <linux/filter.h>
  27 #include <linux/version.h>
  28 #include <linux/kernel.h>
  29 #include <linux/idr.h>
  30 #include <linux/cred.h>
  31 #include <linux/timekeeping.h>
  32 #include <linux/ctype.h>
  33 #include <linux/nospec.h>
  34
  35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
  36                            (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_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
  40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
  41
  42 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
  43
  44 DEFINE_PER_CPU(int, bpf_prog_active);
  45 static DEFINE_IDR(prog_idr);
  46 static DEFINE_SPINLOCK(prog_idr_lock);
  47 static DEFINE_IDR(map_idr);
  48 static DEFINE_SPINLOCK(map_idr_lock);
  49
  50 int sysctl_unprivileged_bpf_disabled __read_mostly;
  51
  52 static const struct bpf_map_ops * const bpf_map_types[] = {
  53 #define BPF_PROG_TYPE(_id, _ops)
  54 #define BPF_MAP_TYPE(_id, _ops) \
  55         [_id] = &_ops,
  56 #include <linux/bpf_types.h>
  57 #undef BPF_PROG_TYPE
  58 #undef BPF_MAP_TYPE
  59 };
  60
  61 /*
  62  * If we're handed a bigger struct than we know of, ensure all the unknown bits
  63  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
  64  * we don't know about yet.
  65  *
  66  * There is a ToCToU between this function call and the following
  67  * copy_from_user() call. However, this is not a concern since this function is
  68  * meant to be a future-proofing of bits.
  69  */
  70 int bpf_check_uarg_tail_zero(void __user *uaddr,
  71                              size_t expected_size,
  72                              size_t actual_size)
  73 {
  74         unsigned char __user *addr;
  75         unsigned char __user *end;
  76         unsigned char val;
  77         int err;
  78
  79         if (unlikely(actual_size > PAGE_SIZE))  /* silly large */
  80                 return -E2BIG;
  81
  82         if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size)))
  83                 return -EFAULT;
  84
  85         if (actual_size <= expected_size)
  86                 return 0;
  87
  88         addr = uaddr + expected_size;
  89         end  = uaddr + actual_size;
  90
  91         for (; addr < end; addr++) {
  92                 err = get_user(val, addr);
  93                 if (err)
  94                         return err;
  95                 if (val)
  96                         return -E2BIG;
  97         }
  98
  99         return 0;
 100 }
 101
 102 const struct bpf_map_ops bpf_map_offload_ops = {
 103         .map_alloc = bpf_map_offload_map_alloc,
 104         .map_free = bpf_map_offload_map_free,
 105         .map_check_btf = map_check_no_btf,
 106 };
 107
 108 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
 109 {
 110         const struct bpf_map_ops *ops;
 111         u32 type = attr->map_type;
 112         struct bpf_map *map;
 113         int err;
 114
 115         if (type >= ARRAY_SIZE(bpf_map_types))
 116                 return ERR_PTR(-EINVAL);
 117         type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
 118         ops = bpf_map_types[type];
 119         if (!ops)
 120                 return ERR_PTR(-EINVAL);
 121
 122         if (ops->map_alloc_check) {
 123                 err = ops->map_alloc_check(attr);
 124                 if (err)
 125                         return ERR_PTR(err);
 126         }
 127         if (attr->map_ifindex)
 128                 ops = &bpf_map_offload_ops;
 129         map = ops->map_alloc(attr);
 130         if (IS_ERR(map))
 131                 return map;
 132         map->ops = ops;
 133         map->map_type = type;
 134         return map;
 135 }
 136
 137 void *bpf_map_area_alloc(size_t size, int numa_node)
 138 {
 139         /* We definitely need __GFP_NORETRY, so OOM killer doesn't
 140          * trigger under memory pressure as we really just want to
 141          * fail instead.
 142          */
 143         const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
 144         void *area;
 145
 146         if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
 147                 area = kmalloc_node(size, GFP_USER | flags, numa_node);
 148                 if (area != NULL)
 149                         return area;
 150         }
 151
 152         return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags,
 153                                            __builtin_return_address(0));
 154 }
 155
 156 void bpf_map_area_free(void *area)
 157 {
 158         kvfree(area);
 159 }
 160
 161 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 162 {
 163         map->map_type = attr->map_type;
 164         map->key_size = attr->key_size;
 165         map->value_size = attr->value_size;
 166         map->max_entries = attr->max_entries;
 167         map->map_flags = attr->map_flags;
 168         map->numa_node = bpf_map_attr_numa_node(attr);
 169 }
 170
 171 int bpf_map_precharge_memlock(u32 pages)
 172 {
 173         struct user_struct *user = get_current_user();
 174         unsigned long memlock_limit, cur;
 175
 176         memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
 177         cur = atomic_long_read(&user->locked_vm);
 178         free_uid(user);
 179         if (cur + pages > memlock_limit)
 180                 return -EPERM;
 181         return 0;
 182 }
 183
 184 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
 185 {
 186         unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
 187
 188         if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
 189                 atomic_long_sub(pages, &user->locked_vm);
 190                 return -EPERM;
 191         }
 192         return 0;
 193 }
 194
 195 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
 196 {
 197         atomic_long_sub(pages, &user->locked_vm);
 198 }
 199
 200 static int bpf_map_init_memlock(struct bpf_map *map)
 201 {
 202         struct user_struct *user = get_current_user();
 203         int ret;
 204
 205         ret = bpf_charge_memlock(user, map->pages);
 206         if (ret) {
 207                 free_uid(user);
 208                 return ret;
 209         }
 210         map->user = user;
 211         return ret;
 212 }
 213
 214 static void bpf_map_release_memlock(struct bpf_map *map)
 215 {
 216         struct user_struct *user = map->user;
 217         bpf_uncharge_memlock(user, map->pages);
 218         free_uid(user);
 219 }
 220
 221 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
 222 {
 223         int ret;
 224
 225         ret = bpf_charge_memlock(map->user, pages);
 226         if (ret)
 227                 return ret;
 228         map->pages += pages;
 229         return ret;
 230 }
 231
 232 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
 233 {
 234         bpf_uncharge_memlock(map->user, pages);
 235         map->pages -= pages;
 236 }
 237
 238 static int bpf_map_alloc_id(struct bpf_map *map)
 239 {
 240         int id;
 241
 242         idr_preload(GFP_KERNEL);
 243         spin_lock_bh(&map_idr_lock);
 244         id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
 245         if (id > 0)
 246                 map->id = id;
 247         spin_unlock_bh(&map_idr_lock);
 248         idr_preload_end();
 249
 250         if (WARN_ON_ONCE(!id))
 251                 return -ENOSPC;
 252
 253         return id > 0 ? 0 : id;
 254 }
 255
 256 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
 257 {
 258         unsigned long flags;
 259
 260         /* Offloaded maps are removed from the IDR store when their device
 261          * disappears - even if someone holds an fd to them they are unusable,
 262          * the memory is gone, all ops will fail; they are simply waiting for
 263          * refcnt to drop to be freed.
 264          */
 265         if (!map->id)
 266                 return;
 267
 268         if (do_idr_lock)
 269                 spin_lock_irqsave(&map_idr_lock, flags);
 270         else
 271                 __acquire(&map_idr_lock);
 272
 273         idr_remove(&map_idr, map->id);
 274         map->id = 0;
 275
 276         if (do_idr_lock)
 277                 spin_unlock_irqrestore(&map_idr_lock, flags);
 278         else
 279                 __release(&map_idr_lock);
 280 }
 281
 282 /* called from workqueue */
 283 static void bpf_map_free_deferred(struct work_struct *work)
 284 {
 285         struct bpf_map *map = container_of(work, struct bpf_map, work);
 286
 287         bpf_map_release_memlock(map);
 288         security_bpf_map_free(map);
 289         /* implementation dependent freeing */
 290         map->ops->map_free(map);
 291 }
 292
 293 static void bpf_map_put_uref(struct bpf_map *map)
 294 {
 295         if (atomic_dec_and_test(&map->usercnt)) {
 296                 if (map->ops->map_release_uref)
 297                         map->ops->map_release_uref(map);
 298         }
 299 }
 300
 301 /* decrement map refcnt and schedule it for freeing via workqueue
 302  * (unrelying map implementation ops->map_free() might sleep)
 303  */
 304 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
 305 {
 306         if (atomic_dec_and_test(&map->refcnt)) {
 307                 /* bpf_map_free_id() must be called first */
 308                 bpf_map_free_id(map, do_idr_lock);
 309                 btf_put(map->btf);
 310                 INIT_WORK(&map->work, bpf_map_free_deferred);
 311                 schedule_work(&map->work);
 312         }
 313 }
 314
 315 void bpf_map_put(struct bpf_map *map)
 316 {
 317         __bpf_map_put(map, true);
 318 }
 319 EXPORT_SYMBOL_GPL(bpf_map_put);
 320
 321 void bpf_map_put_with_uref(struct bpf_map *map)
 322 {
 323         bpf_map_put_uref(map);
 324         bpf_map_put(map);
 325 }
 326
 327 static int bpf_map_release(struct inode *inode, struct file *filp)
 328 {
 329         struct bpf_map *map = filp->private_data;
 330
 331         if (map->ops->map_release)
 332                 map->ops->map_release(map, filp);
 333
 334         bpf_map_put_with_uref(map);
 335         return 0;
 336 }
 337
 338 #ifdef CONFIG_PROC_FS
 339 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 340 {
 341         const struct bpf_map *map = filp->private_data;
 342         const struct bpf_array *array;
 343         u32 owner_prog_type = 0;
 344         u32 owner_jited = 0;
 345
 346         if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
 347                 array = container_of(map, struct bpf_array, map);
 348                 owner_prog_type = array->owner_prog_type;
 349                 owner_jited = array->owner_jited;
 350         }
 351
 352         seq_printf(m,
 353                    "map_type:\t%u\n"
 354                    "key_size:\t%u\n"
 355                    "value_size:\t%u\n"
 356                    "max_entries:\t%u\n"
 357                    "map_flags:\t%#x\n"
 358                    "memlock:\t%llu\n"
 359                    "map_id:\t%u\n",
 360                    map->map_type,
 361                    map->key_size,
 362                    map->value_size,
 363                    map->max_entries,
 364                    map->map_flags,
 365                    map->pages * 1ULL << PAGE_SHIFT,
 366                    map->id);
 367
 368         if (owner_prog_type) {
 369                 seq_printf(m, "owner_prog_type:\t%u\n",
 370                            owner_prog_type);
 371                 seq_printf(m, "owner_jited:\t%u\n",
 372                            owner_jited);
 373         }
 374 }
 375 #endif
 376
 377 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
 378                               loff_t *ppos)
 379 {
 380         /* We need this handler such that alloc_file() enables
 381          * f_mode with FMODE_CAN_READ.
 382          */
 383         return -EINVAL;
 384 }
 385
 386 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
 387                                size_t siz, loff_t *ppos)
 388 {
 389         /* We need this handler such that alloc_file() enables
 390          * f_mode with FMODE_CAN_WRITE.
 391          */
 392         return -EINVAL;
 393 }
 394
 395 const struct file_operations bpf_map_fops = {
 396 #ifdef CONFIG_PROC_FS
 397         .show_fdinfo    = bpf_map_show_fdinfo,
 398 #endif
 399         .release        = bpf_map_release,
 400         .read           = bpf_dummy_read,
 401         .write          = bpf_dummy_write,
 402 };
 403
 404 int bpf_map_new_fd(struct bpf_map *map, int flags)
 405 {
 406         int ret;
 407
 408         ret = security_bpf_map(map, OPEN_FMODE(flags));
 409         if (ret < 0)
 410                 return ret;
 411
 412         return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
 413                                 flags | O_CLOEXEC);
 414 }
 415
 416 int bpf_get_file_flag(int flags)
 417 {
 418         if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
 419                 return -EINVAL;
 420         if (flags & BPF_F_RDONLY)
 421                 return O_RDONLY;
 422         if (flags & BPF_F_WRONLY)
 423                 return O_WRONLY;
 424         return O_RDWR;
 425 }
 426
 427 /* helper macro to check that unused fields 'union bpf_attr' are zero */
 428 #define CHECK_ATTR(CMD) \
 429         memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
 430                    sizeof(attr->CMD##_LAST_FIELD), 0, \
 431                    sizeof(*attr) - \
 432                    offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
 433                    sizeof(attr->CMD##_LAST_FIELD)) != NULL
 434
 435 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
 436  * Return 0 on success and < 0 on error.
 437  */
 438 static int bpf_obj_name_cpy(char *dst, const char *src)
 439 {
 440         const char *end = src + BPF_OBJ_NAME_LEN;
 441
 442         memset(dst, 0, BPF_OBJ_NAME_LEN);
 443
 444         /* Copy all isalnum() and '_' char */
 445         while (src < end && *src) {
 446                 if (!isalnum(*src) && *src != '_')
 447                         return -EINVAL;
 448                 *dst++ = *src++;
 449         }
 450
 451         /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
 452         if (src == end)
 453                 return -EINVAL;
 454
 455         return 0;
 456 }
 457
 458 int map_check_no_btf(const struct bpf_map *map,
 459                      const struct btf_type *key_type,
 460                      const struct btf_type *value_type)
 461 {
 462         return -ENOTSUPP;
 463 }
 464
 465 static int map_check_btf(const struct bpf_map *map, const struct btf *btf,
 466                          u32 btf_key_id, u32 btf_value_id)
 467 {
 468         const struct btf_type *key_type, *value_type;
 469         u32 key_size, value_size;
 470         int ret = 0;
 471
 472         key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
 473         if (!key_type || key_size != map->key_size)
 474                 return -EINVAL;
 475
 476         value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
 477         if (!value_type || value_size != map->value_size)
 478                 return -EINVAL;
 479
 480         if (map->ops->map_check_btf)
 481                 ret = map->ops->map_check_btf(map, key_type, value_type);
 482
 483         return ret;
 484 }
 485
 486 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
 487 /* called via syscall */
 488 static int map_create(union bpf_attr *attr)
 489 {
 490         int numa_node = bpf_map_attr_numa_node(attr);
 491         struct bpf_map *map;
 492         int f_flags;
 493         int err;
 494
 495         err = CHECK_ATTR(BPF_MAP_CREATE);
 496         if (err)
 497                 return -EINVAL;
 498
 499         f_flags = bpf_get_file_flag(attr->map_flags);
 500         if (f_flags < 0)
 501                 return f_flags;
 502
 503         if (numa_node != NUMA_NO_NODE &&
 504             ((unsigned int)numa_node >= nr_node_ids ||
 505              !node_online(numa_node)))
 506                 return -EINVAL;
 507
 508         /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
 509         map = find_and_alloc_map(attr);
 510         if (IS_ERR(map))
 511                 return PTR_ERR(map);
 512
 513         err = bpf_obj_name_cpy(map->name, attr->map_name);
 514         if (err)
 515                 goto free_map_nouncharge;
 516
 517         atomic_set(&map->refcnt, 1);
 518         atomic_set(&map->usercnt, 1);
 519
 520         if (attr->btf_key_type_id || attr->btf_value_type_id) {
 521                 struct btf *btf;
 522
 523                 if (!attr->btf_key_type_id || !attr->btf_value_type_id) {
 524                         err = -EINVAL;
 525                         goto free_map_nouncharge;
 526                 }
 527
 528                 btf = btf_get_by_fd(attr->btf_fd);
 529                 if (IS_ERR(btf)) {
 530                         err = PTR_ERR(btf);
 531                         goto free_map_nouncharge;
 532                 }
 533
 534                 err = map_check_btf(map, btf, attr->btf_key_type_id,
 535                                     attr->btf_value_type_id);
 536                 if (err) {
 537                         btf_put(btf);
 538                         goto free_map_nouncharge;
 539                 }
 540
 541                 map->btf = btf;
 542                 map->btf_key_type_id = attr->btf_key_type_id;
 543                 map->btf_value_type_id = attr->btf_value_type_id;
 544         }
 545
 546         err = security_bpf_map_alloc(map);
 547         if (err)
 548                 goto free_map_nouncharge;
 549
 550         err = bpf_map_init_memlock(map);
 551         if (err)
 552                 goto free_map_sec;
 553
 554         err = bpf_map_alloc_id(map);
 555         if (err)
 556                 goto free_map;
 557
 558         err = bpf_map_new_fd(map, f_flags);
 559         if (err < 0) {
 560                 /* failed to allocate fd.
 561                  * bpf_map_put() is needed because the above
 562                  * bpf_map_alloc_id() has published the map
 563                  * to the userspace and the userspace may
 564                  * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
 565                  */
 566                 bpf_map_put(map);
 567                 return err;
 568         }
 569
 570         return err;
 571
 572 free_map:
 573         bpf_map_release_memlock(map);
 574 free_map_sec:
 575         security_bpf_map_free(map);
 576 free_map_nouncharge:
 577         btf_put(map->btf);
 578         map->ops->map_free(map);
 579         return err;
 580 }
 581
 582 /* if error is returned, fd is released.
 583  * On success caller should complete fd access with matching fdput()
 584  */
 585 struct bpf_map *__bpf_map_get(struct fd f)
 586 {
 587         if (!f.file)
 588                 return ERR_PTR(-EBADF);
 589         if (f.file->f_op != &bpf_map_fops) {
 590                 fdput(f);
 591                 return ERR_PTR(-EINVAL);
 592         }
 593
 594         return f.file->private_data;
 595 }
 596
 597 /* prog's and map's refcnt limit */
 598 #define BPF_MAX_REFCNT 32768
 599
 600 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
 601 {
 602         if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
 603                 atomic_dec(&map->refcnt);
 604                 return ERR_PTR(-EBUSY);
 605         }
 606         if (uref)
 607                 atomic_inc(&map->usercnt);
 608         return map;
 609 }
 610 EXPORT_SYMBOL_GPL(bpf_map_inc);
 611
 612 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
 613 {
 614         struct fd f = fdget(ufd);
 615         struct bpf_map *map;
 616
 617         map = __bpf_map_get(f);
 618         if (IS_ERR(map))
 619                 return map;
 620
 621         map = bpf_map_inc(map, true);
 622         fdput(f);
 623
 624         return map;
 625 }
 626
 627 /* map_idr_lock should have been held */
 628 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
 629                                             bool uref)
 630 {
 631         int refold;
 632
 633         refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
 634
 635         if (refold >= BPF_MAX_REFCNT) {
 636                 __bpf_map_put(map, false);
 637                 return ERR_PTR(-EBUSY);
 638         }
 639
 640         if (!refold)
 641                 return ERR_PTR(-ENOENT);
 642
 643         if (uref)
 644                 atomic_inc(&map->usercnt);
 645
 646         return map;
 647 }
 648
 649 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
 650 {
 651         return -ENOTSUPP;
 652 }
 653
 654 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
 655 {
 656         if (key_size)
 657                 return memdup_user(ukey, key_size);
 658
 659         if (ukey)
 660                 return ERR_PTR(-EINVAL);
 661
 662         return NULL;
 663 }
 664
 665 /* last field in 'union bpf_attr' used by this command */
 666 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
 667
 668 static int map_lookup_elem(union bpf_attr *attr)
 669 {
 670         void __user *ukey = u64_to_user_ptr(attr->key);
 671         void __user *uvalue = u64_to_user_ptr(attr->value);
 672         int ufd = attr->map_fd;
 673         struct bpf_map *map;
 674         void *key, *value, *ptr;
 675         u32 value_size;
 676         struct fd f;
 677         int err;
 678
 679         if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
 680                 return -EINVAL;
 681
 682         f = fdget(ufd);
 683         map = __bpf_map_get(f);
 684         if (IS_ERR(map))
 685                 return PTR_ERR(map);
 686
 687         if (!(f.file->f_mode & FMODE_CAN_READ)) {
 688                 err = -EPERM;
 689                 goto err_put;
 690         }
 691
 692         key = __bpf_copy_key(ukey, map->key_size);
 693         if (IS_ERR(key)) {
 694                 err = PTR_ERR(key);
 695                 goto err_put;
 696         }
 697
 698         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 699             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
 700             map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 701             map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 702                 value_size = round_up(map->value_size, 8) * num_possible_cpus();
 703         else if (IS_FD_MAP(map))
 704                 value_size = sizeof(u32);
 705         else
 706                 value_size = map->value_size;
 707
 708         err = -ENOMEM;
 709         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
 710         if (!value)
 711                 goto free_key;
 712
 713         if (bpf_map_is_dev_bound(map)) {
 714                 err = bpf_map_offload_lookup_elem(map, key, value);
 715         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 716                    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 717                 err = bpf_percpu_hash_copy(map, key, value);
 718         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 719                 err = bpf_percpu_array_copy(map, key, value);
 720         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 721                 err = bpf_percpu_cgroup_storage_copy(map, key, value);
 722         } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
 723                 err = bpf_stackmap_copy(map, key, value);
 724         } else if (IS_FD_ARRAY(map)) {
 725                 err = bpf_fd_array_map_lookup_elem(map, key, value);
 726         } else if (IS_FD_HASH(map)) {
 727                 err = bpf_fd_htab_map_lookup_elem(map, key, value);
 728         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 729                 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
 730         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 731                    map->map_type == BPF_MAP_TYPE_STACK) {
 732                 err = map->ops->map_peek_elem(map, value);
 733         } else {
 734                 rcu_read_lock();
 735                 ptr = map->ops->map_lookup_elem(map, key);
 736                 if (IS_ERR(ptr)) {
 737                         err = PTR_ERR(ptr);
 738                 } else if (!ptr) {
 739                         err = -ENOENT;
 740                 } else {
 741                         err = 0;
 742                         memcpy(value, ptr, value_size);
 743                 }
 744                 rcu_read_unlock();
 745         }
 746
 747         if (err)
 748                 goto free_value;
 749
 750         err = -EFAULT;
 751         if (copy_to_user(uvalue, value, value_size) != 0)
 752                 goto free_value;
 753
 754         err = 0;
 755
 756 free_value:
 757         kfree(value);
 758 free_key:
 759         kfree(key);
 760 err_put:
 761         fdput(f);
 762         return err;
 763 }
 764
 765 static void maybe_wait_bpf_programs(struct bpf_map *map)
 766 {
 767         /* Wait for any running BPF programs to complete so that
 768          * userspace, when we return to it, knows that all programs
 769          * that could be running use the new map value.
 770          */
 771         if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
 772             map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
 773                 synchronize_rcu();
 774 }
 775
 776 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
 777
 778 static int map_update_elem(union bpf_attr *attr)
 779 {
 780         void __user *ukey = u64_to_user_ptr(attr->key);
 781         void __user *uvalue = u64_to_user_ptr(attr->value);
 782         int ufd = attr->map_fd;
 783         struct bpf_map *map;
 784         void *key, *value;
 785         u32 value_size;
 786         struct fd f;
 787         int err;
 788
 789         if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
 790                 return -EINVAL;
 791
 792         f = fdget(ufd);
 793         map = __bpf_map_get(f);
 794         if (IS_ERR(map))
 795                 return PTR_ERR(map);
 796
 797         if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
 798                 err = -EPERM;
 799                 goto err_put;
 800         }
 801
 802         key = __bpf_copy_key(ukey, map->key_size);
 803         if (IS_ERR(key)) {
 804                 err = PTR_ERR(key);
 805                 goto err_put;
 806         }
 807
 808         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 809             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
 810             map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 811             map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 812                 value_size = round_up(map->value_size, 8) * num_possible_cpus();
 813         else
 814                 value_size = map->value_size;
 815
 816         err = -ENOMEM;
 817         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
 818         if (!value)
 819                 goto free_key;
 820
 821         err = -EFAULT;
 822         if (copy_from_user(value, uvalue, value_size) != 0)
 823                 goto free_value;
 824
 825         /* Need to create a kthread, thus must support schedule */
 826         if (bpf_map_is_dev_bound(map)) {
 827                 err = bpf_map_offload_update_elem(map, key, value, attr->flags);
 828                 goto out;
 829         } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
 830                    map->map_type == BPF_MAP_TYPE_SOCKHASH ||
 831                    map->map_type == BPF_MAP_TYPE_SOCKMAP) {
 832                 err = map->ops->map_update_elem(map, key, value, attr->flags);
 833                 goto out;
 834         }
 835
 836         /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
 837          * inside bpf map update or delete otherwise deadlocks are possible
 838          */
 839         preempt_disable();
 840         __this_cpu_inc(bpf_prog_active);
 841         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 842             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 843                 err = bpf_percpu_hash_update(map, key, value, attr->flags);
 844         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 845                 err = bpf_percpu_array_update(map, key, value, attr->flags);
 846         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 847                 err = bpf_percpu_cgroup_storage_update(map, key, value,
 848                                                        attr->flags);
 849         } else if (IS_FD_ARRAY(map)) {
 850                 rcu_read_lock();
 851                 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
 852                                                    attr->flags);
 853                 rcu_read_unlock();
 854         } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
 855                 rcu_read_lock();
 856                 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
 857                                                   attr->flags);
 858                 rcu_read_unlock();
 859         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 860                 /* rcu_read_lock() is not needed */
 861                 err = bpf_fd_reuseport_array_update_elem(map, key, value,
 862                                                          attr->flags);
 863         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 864                    map->map_type == BPF_MAP_TYPE_STACK) {
 865                 err = map->ops->map_push_elem(map, value, attr->flags);
 866         } else {
 867                 rcu_read_lock();
 868                 err = map->ops->map_update_elem(map, key, value, attr->flags);
 869                 rcu_read_unlock();
 870         }
 871         __this_cpu_dec(bpf_prog_active);
 872         preempt_enable();
 873         maybe_wait_bpf_programs(map);
 874 out:
 875 free_value:
 876         kfree(value);
 877 free_key:
 878         kfree(key);
 879 err_put:
 880         fdput(f);
 881         return err;
 882 }
 883
 884 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
 885
 886 static int map_delete_elem(union bpf_attr *attr)
 887 {
 888         void __user *ukey = u64_to_user_ptr(attr->key);
 889         int ufd = attr->map_fd;
 890         struct bpf_map *map;
 891         struct fd f;
 892         void *key;
 893         int err;
 894
 895         if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
 896                 return -EINVAL;
 897
 898         f = fdget(ufd);
 899         map = __bpf_map_get(f);
 900         if (IS_ERR(map))
 901                 return PTR_ERR(map);
 902
 903         if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
 904                 err = -EPERM;
 905                 goto err_put;
 906         }
 907
 908         key = __bpf_copy_key(ukey, map->key_size);
 909         if (IS_ERR(key)) {
 910                 err = PTR_ERR(key);
 911                 goto err_put;
 912         }
 913
 914         if (bpf_map_is_dev_bound(map)) {
 915                 err = bpf_map_offload_delete_elem(map, key);
 916                 goto out;
 917         }
 918
 919         preempt_disable();
 920         __this_cpu_inc(bpf_prog_active);
 921         rcu_read_lock();
 922         err = map->ops->map_delete_elem(map, key);
 923         rcu_read_unlock();
 924         __this_cpu_dec(bpf_prog_active);
 925         preempt_enable();
 926         maybe_wait_bpf_programs(map);
 927 out:
 928         kfree(key);
 929 err_put:
 930         fdput(f);
 931         return err;
 932 }
 933
 934 /* last field in 'union bpf_attr' used by this command */
 935 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
 936
 937 static int map_get_next_key(union bpf_attr *attr)
 938 {
 939         void __user *ukey = u64_to_user_ptr(attr->key);
 940         void __user *unext_key = u64_to_user_ptr(attr->next_key);
 941         int ufd = attr->map_fd;
 942         struct bpf_map *map;
 943         void *key, *next_key;
 944         struct fd f;
 945         int err;
 946
 947         if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
 948                 return -EINVAL;
 949
 950         f = fdget(ufd);
 951         map = __bpf_map_get(f);
 952         if (IS_ERR(map))
 953                 return PTR_ERR(map);
 954
 955         if (!(f.file->f_mode & FMODE_CAN_READ)) {
 956                 err = -EPERM;
 957                 goto err_put;
 958         }
 959
 960         if (ukey) {
 961                 key = __bpf_copy_key(ukey, map->key_size);
 962                 if (IS_ERR(key)) {
 963                         err = PTR_ERR(key);
 964                         goto err_put;
 965                 }
 966         } else {
 967                 key = NULL;
 968         }
 969
 970         err = -ENOMEM;
 971         next_key = kmalloc(map->key_size, GFP_USER);
 972         if (!next_key)
 973                 goto free_key;
 974
 975         if (bpf_map_is_dev_bound(map)) {
 976                 err = bpf_map_offload_get_next_key(map, key, next_key);
 977                 goto out;
 978         }
 979
 980         rcu_read_lock();
 981         err = map->ops->map_get_next_key(map, key, next_key);
 982         rcu_read_unlock();
 983 out:
 984         if (err)
 985                 goto free_next_key;
 986
 987         err = -EFAULT;
 988         if (copy_to_user(unext_key, next_key, map->key_size) != 0)
 989                 goto free_next_key;
 990
 991         err = 0;
 992
 993 free_next_key:
 994         kfree(next_key);
 995 free_key:
 996         kfree(key);
 997 err_put:
 998         fdput(f);
 999         return err;
1000 }
1001
1002 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1003
1004 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1005 {
1006         void __user *ukey = u64_to_user_ptr(attr->key);
1007         void __user *uvalue = u64_to_user_ptr(attr->value);
1008         int ufd = attr->map_fd;
1009         struct bpf_map *map;
1010         void *key, *value;
1011         u32 value_size;
1012         struct fd f;
1013         int err;
1014
1015         if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1016                 return -EINVAL;
1017
1018         f = fdget(ufd);
1019         map = __bpf_map_get(f);
1020         if (IS_ERR(map))
1021                 return PTR_ERR(map);
1022
1023         if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
1024                 err = -EPERM;
1025                 goto err_put;
1026         }
1027
1028         key = __bpf_copy_key(ukey, map->key_size);
1029         if (IS_ERR(key)) {
1030                 err = PTR_ERR(key);
1031                 goto err_put;
1032         }
1033
1034         value_size = map->value_size;
1035
1036         err = -ENOMEM;
1037         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1038         if (!value)
1039                 goto free_key;
1040
1041         if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1042             map->map_type == BPF_MAP_TYPE_STACK) {
1043                 err = map->ops->map_pop_elem(map, value);
1044         } else {
1045                 err = -ENOTSUPP;
1046         }
1047
1048         if (err)
1049                 goto free_value;
1050
1051         if (copy_to_user(uvalue, value, value_size) != 0)
1052                 goto free_value;
1053
1054         err = 0;
1055
1056 free_value:
1057         kfree(value);
1058 free_key:
1059         kfree(key);
1060 err_put:
1061         fdput(f);
1062         return err;
1063 }
1064
1065 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1066 #define BPF_PROG_TYPE(_id, _name) \
1067         [_id] = & _name ## _prog_ops,
1068 #define BPF_MAP_TYPE(_id, _ops)
1069 #include <linux/bpf_types.h>
1070 #undef BPF_PROG_TYPE
1071 #undef BPF_MAP_TYPE
1072 };
1073
1074 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1075 {
1076         const struct bpf_prog_ops *ops;
1077
1078         if (type >= ARRAY_SIZE(bpf_prog_types))
1079                 return -EINVAL;
1080         type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1081         ops = bpf_prog_types[type];
1082         if (!ops)
1083                 return -EINVAL;
1084
1085         if (!bpf_prog_is_dev_bound(prog->aux))
1086                 prog->aux->ops = ops;
1087         else
1088                 prog->aux->ops = &bpf_offload_prog_ops;
1089         prog->type = type;
1090         return 0;
1091 }
1092
1093 /* drop refcnt on maps used by eBPF program and free auxilary data */
1094 static void free_used_maps(struct bpf_prog_aux *aux)
1095 {
1096         enum bpf_cgroup_storage_type stype;
1097         int i;
1098
1099         for_each_cgroup_storage_type(stype) {
1100                 if (!aux->cgroup_storage[stype])
1101                         continue;
1102                 bpf_cgroup_storage_release(aux->prog,
1103                                            aux->cgroup_storage[stype]);
1104         }
1105
1106         for (i = 0; i < aux->used_map_cnt; i++)
1107                 bpf_map_put(aux->used_maps[i]);
1108
1109         kfree(aux->used_maps);
1110 }
1111
1112 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1113 {
1114         unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1115         unsigned long user_bufs;
1116
1117         if (user) {
1118                 user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1119                 if (user_bufs > memlock_limit) {
1120                         atomic_long_sub(pages, &user->locked_vm);
1121                         return -EPERM;
1122                 }
1123         }
1124
1125         return 0;
1126 }
1127
1128 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1129 {
1130         if (user)
1131                 atomic_long_sub(pages, &user->locked_vm);
1132 }
1133
1134 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1135 {
1136         struct user_struct *user = get_current_user();
1137         int ret;
1138
1139         ret = __bpf_prog_charge(user, prog->pages);
1140         if (ret) {
1141                 free_uid(user);
1142                 return ret;
1143         }
1144
1145         prog->aux->user = user;
1146         return 0;
1147 }
1148
1149 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1150 {
1151         struct user_struct *user = prog->aux->user;
1152
1153         __bpf_prog_uncharge(user, prog->pages);
1154         free_uid(user);
1155 }
1156
1157 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1158 {
1159         int id;
1160
1161         idr_preload(GFP_KERNEL);
1162         spin_lock_bh(&prog_idr_lock);
1163         id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1164         if (id > 0)
1165                 prog->aux->id = id;
1166         spin_unlock_bh(&prog_idr_lock);
1167         idr_preload_end();
1168
1169         /* id is in [1, INT_MAX) */
1170         if (WARN_ON_ONCE(!id))
1171                 return -ENOSPC;
1172
1173         return id > 0 ? 0 : id;
1174 }
1175
1176 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1177 {
1178         /* cBPF to eBPF migrations are currently not in the idr store.
1179          * Offloaded programs are removed from the store when their device
1180          * disappears - even if someone grabs an fd to them they are unusable,
1181          * simply waiting for refcnt to drop to be freed.
1182          */
1183         if (!prog->aux->id)
1184                 return;
1185
1186         if (do_idr_lock)
1187                 spin_lock_bh(&prog_idr_lock);
1188         else
1189                 __acquire(&prog_idr_lock);
1190
1191         idr_remove(&prog_idr, prog->aux->id);
1192         prog->aux->id = 0;
1193
1194         if (do_idr_lock)
1195                 spin_unlock_bh(&prog_idr_lock);
1196         else
1197                 __release(&prog_idr_lock);
1198 }
1199
1200 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1201 {
1202         struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1203
1204         free_used_maps(aux);
1205         bpf_prog_uncharge_memlock(aux->prog);
1206         security_bpf_prog_free(aux);
1207         bpf_prog_free(aux->prog);
1208 }
1209
1210 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1211 {
1212         if (atomic_dec_and_test(&prog->aux->refcnt)) {
1213                 /* bpf_prog_free_id() must be called first */
1214                 bpf_prog_free_id(prog, do_idr_lock);
1215                 bpf_prog_kallsyms_del_all(prog);
1216
1217                 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1218         }
1219 }
1220
1221 void bpf_prog_put(struct bpf_prog *prog)
1222 {
1223         __bpf_prog_put(prog, true);
1224 }
1225 EXPORT_SYMBOL_GPL(bpf_prog_put);
1226
1227 static int bpf_prog_release(struct inode *inode, struct file *filp)
1228 {
1229         struct bpf_prog *prog = filp->private_data;
1230
1231         bpf_prog_put(prog);
1232         return 0;
1233 }
1234
1235 #ifdef CONFIG_PROC_FS
1236 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1237 {
1238         const struct bpf_prog *prog = filp->private_data;
1239         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1240
1241         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1242         seq_printf(m,
1243                    "prog_type:\t%u\n"
1244                    "prog_jited:\t%u\n"
1245                    "prog_tag:\t%s\n"
1246                    "memlock:\t%llu\n"
1247                    "prog_id:\t%u\n",
1248                    prog->type,
1249                    prog->jited,
1250                    prog_tag,
1251                    prog->pages * 1ULL << PAGE_SHIFT,
1252                    prog->aux->id);
1253 }
1254 #endif
1255
1256 const struct file_operations bpf_prog_fops = {
1257 #ifdef CONFIG_PROC_FS
1258         .show_fdinfo    = bpf_prog_show_fdinfo,
1259 #endif
1260         .release        = bpf_prog_release,
1261         .read           = bpf_dummy_read,
1262         .write          = bpf_dummy_write,
1263 };
1264
1265 int bpf_prog_new_fd(struct bpf_prog *prog)
1266 {
1267         int ret;
1268
1269         ret = security_bpf_prog(prog);
1270         if (ret < 0)
1271                 return ret;
1272
1273         return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1274                                 O_RDWR | O_CLOEXEC);
1275 }
1276
1277 static struct bpf_prog *____bpf_prog_get(struct fd f)
1278 {
1279         if (!f.file)
1280                 return ERR_PTR(-EBADF);
1281         if (f.file->f_op != &bpf_prog_fops) {
1282                 fdput(f);
1283                 return ERR_PTR(-EINVAL);
1284         }
1285
1286         return f.file->private_data;
1287 }
1288
1289 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1290 {
1291         if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1292                 atomic_sub(i, &prog->aux->refcnt);
1293                 return ERR_PTR(-EBUSY);
1294         }
1295         return prog;
1296 }
1297 EXPORT_SYMBOL_GPL(bpf_prog_add);
1298
1299 void bpf_prog_sub(struct bpf_prog *prog, int i)
1300 {
1301         /* Only to be used for undoing previous bpf_prog_add() in some
1302          * error path. We still know that another entity in our call
1303          * path holds a reference to the program, thus atomic_sub() can
1304          * be safely used in such cases!
1305          */
1306         WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1307 }
1308 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1309
1310 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1311 {
1312         return bpf_prog_add(prog, 1);
1313 }
1314 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1315
1316 /* prog_idr_lock should have been held */
1317 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1318 {
1319         int refold;
1320
1321         refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1322
1323         if (refold >= BPF_MAX_REFCNT) {
1324                 __bpf_prog_put(prog, false);
1325                 return ERR_PTR(-EBUSY);
1326         }
1327
1328         if (!refold)
1329                 return ERR_PTR(-ENOENT);
1330
1331         return prog;
1332 }
1333 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1334
1335 bool bpf_prog_get_ok(struct bpf_prog *prog,
1336                             enum bpf_prog_type *attach_type, bool attach_drv)
1337 {
1338         /* not an attachment, just a refcount inc, always allow */
1339         if (!attach_type)
1340                 return true;
1341
1342         if (prog->type != *attach_type)
1343                 return false;
1344         if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1345                 return false;
1346
1347         return true;
1348 }
1349
1350 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1351                                        bool attach_drv)
1352 {
1353         struct fd f = fdget(ufd);
1354         struct bpf_prog *prog;
1355
1356         prog = ____bpf_prog_get(f);
1357         if (IS_ERR(prog))
1358                 return prog;
1359         if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1360                 prog = ERR_PTR(-EINVAL);
1361                 goto out;
1362         }
1363
1364         prog = bpf_prog_inc(prog);
1365 out:
1366         fdput(f);
1367         return prog;
1368 }
1369
1370 struct bpf_prog *bpf_prog_get(u32 ufd)
1371 {
1372         return __bpf_prog_get(ufd, NULL, false);
1373 }
1374
1375 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1376                                        bool attach_drv)
1377 {
1378         return __bpf_prog_get(ufd, &type, attach_drv);
1379 }
1380 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1381
1382 /* Initially all BPF programs could be loaded w/o specifying
1383  * expected_attach_type. Later for some of them specifying expected_attach_type
1384  * at load time became required so that program could be validated properly.
1385  * Programs of types that are allowed to be loaded both w/ and w/o (for
1386  * backward compatibility) expected_attach_type, should have the default attach
1387  * type assigned to expected_attach_type for the latter case, so that it can be
1388  * validated later at attach time.
1389  *
1390  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1391  * prog type requires it but has some attach types that have to be backward
1392  * compatible.
1393  */
1394 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1395 {
1396         switch (attr->prog_type) {
1397         case BPF_PROG_TYPE_CGROUP_SOCK:
1398                 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1399                  * exist so checking for non-zero is the way to go here.
1400                  */
1401                 if (!attr->expected_attach_type)
1402                         attr->expected_attach_type =
1403                                 BPF_CGROUP_INET_SOCK_CREATE;
1404                 break;
1405         }
1406 }
1407
1408 static int
1409 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1410                                 enum bpf_attach_type expected_attach_type)
1411 {
1412         switch (prog_type) {
1413         case BPF_PROG_TYPE_CGROUP_SOCK:
1414                 switch (expected_attach_type) {
1415                 case BPF_CGROUP_INET_SOCK_CREATE:
1416                 case BPF_CGROUP_INET4_POST_BIND:
1417                 case BPF_CGROUP_INET6_POST_BIND:
1418                         return 0;
1419                 default:
1420                         return -EINVAL;
1421                 }
1422         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1423                 switch (expected_attach_type) {
1424                 case BPF_CGROUP_INET4_BIND:
1425                 case BPF_CGROUP_INET6_BIND:
1426                 case BPF_CGROUP_INET4_CONNECT:
1427                 case BPF_CGROUP_INET6_CONNECT:
1428                 case BPF_CGROUP_UDP4_SENDMSG:
1429                 case BPF_CGROUP_UDP6_SENDMSG:
1430                         return 0;
1431                 default:
1432                         return -EINVAL;
1433                 }
1434         default:
1435                 return 0;
1436         }
1437 }
1438
1439 /* last field in 'union bpf_attr' used by this command */
1440 #define BPF_PROG_LOAD_LAST_FIELD expected_attach_type
1441
1442 static int bpf_prog_load(union bpf_attr *attr)
1443 {
1444         enum bpf_prog_type type = attr->prog_type;
1445         struct bpf_prog *prog;
1446         int err;
1447         char license[128];
1448         bool is_gpl;
1449
1450         if (CHECK_ATTR(BPF_PROG_LOAD))
1451                 return -EINVAL;
1452
1453         if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT)
1454                 return -EINVAL;
1455
1456         /* copy eBPF program license from user space */
1457         if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1458                               sizeof(license) - 1) < 0)
1459                 return -EFAULT;
1460         license[sizeof(license) - 1] = 0;
1461
1462         /* eBPF programs must be GPL compatible to use GPL-ed functions */
1463         is_gpl = license_is_gpl_compatible(license);
1464
1465         if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS)
1466                 return -E2BIG;
1467
1468         if (type == BPF_PROG_TYPE_KPROBE &&
1469             attr->kern_version != LINUX_VERSION_CODE)
1470                 return -EINVAL;
1471
1472         if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1473             type != BPF_PROG_TYPE_CGROUP_SKB &&
1474             !capable(CAP_SYS_ADMIN))
1475                 return -EPERM;
1476
1477         bpf_prog_load_fixup_attach_type(attr);
1478         if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1479                 return -EINVAL;
1480
1481         /* plain bpf_prog allocation */
1482         prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1483         if (!prog)
1484                 return -ENOMEM;
1485
1486         prog->expected_attach_type = attr->expected_attach_type;
1487
1488         prog->aux->offload_requested = !!attr->prog_ifindex;
1489
1490         err = security_bpf_prog_alloc(prog->aux);
1491         if (err)
1492                 goto free_prog_nouncharge;
1493
1494         err = bpf_prog_charge_memlock(prog);
1495         if (err)
1496                 goto free_prog_sec;
1497
1498         prog->len = attr->insn_cnt;
1499
1500         err = -EFAULT;
1501         if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1502                            bpf_prog_insn_size(prog)) != 0)
1503                 goto free_prog;
1504
1505         prog->orig_prog = NULL;
1506         prog->jited = 0;
1507
1508         atomic_set(&prog->aux->refcnt, 1);
1509         prog->gpl_compatible = is_gpl ? 1 : 0;
1510
1511         if (bpf_prog_is_dev_bound(prog->aux)) {
1512                 err = bpf_prog_offload_init(prog, attr);
1513                 if (err)
1514                         goto free_prog;
1515         }
1516
1517         /* find program type: socket_filter vs tracing_filter */
1518         err = find_prog_type(type, prog);
1519         if (err < 0)
1520                 goto free_prog;
1521
1522         prog->aux->load_time = ktime_get_boot_ns();
1523         err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1524         if (err)
1525                 goto free_prog;
1526
1527         /* run eBPF verifier */
1528         err = bpf_check(&prog, attr);
1529         if (err < 0)
1530                 goto free_used_maps;
1531
1532         prog = bpf_prog_select_runtime(prog, &err);
1533         if (err < 0)
1534                 goto free_used_maps;
1535
1536         err = bpf_prog_alloc_id(prog);
1537         if (err)
1538                 goto free_used_maps;
1539
1540         err = bpf_prog_new_fd(prog);
1541         if (err < 0) {
1542                 /* failed to allocate fd.
1543                  * bpf_prog_put() is needed because the above
1544                  * bpf_prog_alloc_id() has published the prog
1545                  * to the userspace and the userspace may
1546                  * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
1547                  */
1548                 bpf_prog_put(prog);
1549                 return err;
1550         }
1551
1552         bpf_prog_kallsyms_add(prog);
1553         return err;
1554
1555 free_used_maps:
1556         bpf_prog_kallsyms_del_subprogs(prog);
1557         free_used_maps(prog->aux);
1558 free_prog:
1559         bpf_prog_uncharge_memlock(prog);
1560 free_prog_sec:
1561         security_bpf_prog_free(prog->aux);
1562 free_prog_nouncharge:
1563         bpf_prog_free(prog);
1564         return err;
1565 }
1566
1567 #define BPF_OBJ_LAST_FIELD file_flags
1568
1569 static int bpf_obj_pin(const union bpf_attr *attr)
1570 {
1571         if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1572                 return -EINVAL;
1573
1574         return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1575 }
1576
1577 static int bpf_obj_get(const union bpf_attr *attr)
1578 {
1579         if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1580             attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1581                 return -EINVAL;
1582
1583         return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1584                                 attr->file_flags);
1585 }
1586
1587 struct bpf_raw_tracepoint {
1588         struct bpf_raw_event_map *btp;
1589         struct bpf_prog *prog;
1590 };
1591
1592 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1593 {
1594         struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1595
1596         if (raw_tp->prog) {
1597                 bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1598                 bpf_prog_put(raw_tp->prog);
1599         }
1600         kfree(raw_tp);
1601         return 0;
1602 }
1603
1604 static const struct file_operations bpf_raw_tp_fops = {
1605         .release        = bpf_raw_tracepoint_release,
1606         .read           = bpf_dummy_read,
1607         .write          = bpf_dummy_write,
1608 };
1609
1610 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1611
1612 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1613 {
1614         struct bpf_raw_tracepoint *raw_tp;
1615         struct bpf_raw_event_map *btp;
1616         struct bpf_prog *prog;
1617         char tp_name[128];
1618         int tp_fd, err;
1619
1620         if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1621                               sizeof(tp_name) - 1) < 0)
1622                 return -EFAULT;
1623         tp_name[sizeof(tp_name) - 1] = 0;
1624
1625         btp = bpf_find_raw_tracepoint(tp_name);
1626         if (!btp)
1627                 return -ENOENT;
1628
1629         raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1630         if (!raw_tp)
1631                 return -ENOMEM;
1632         raw_tp->btp = btp;
1633
1634         prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
1635                                  BPF_PROG_TYPE_RAW_TRACEPOINT);
1636         if (IS_ERR(prog)) {
1637                 err = PTR_ERR(prog);
1638                 goto out_free_tp;
1639         }
1640
1641         err = bpf_probe_register(raw_tp->btp, prog);
1642         if (err)
1643                 goto out_put_prog;
1644
1645         raw_tp->prog = prog;
1646         tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1647                                  O_CLOEXEC);
1648         if (tp_fd < 0) {
1649                 bpf_probe_unregister(raw_tp->btp, prog);
1650                 err = tp_fd;
1651                 goto out_put_prog;
1652         }
1653         return tp_fd;
1654
1655 out_put_prog:
1656         bpf_prog_put(prog);
1657 out_free_tp:
1658         kfree(raw_tp);
1659         return err;
1660 }
1661
1662 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1663                                              enum bpf_attach_type attach_type)
1664 {
1665         switch (prog->type) {
1666         case BPF_PROG_TYPE_CGROUP_SOCK:
1667         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1668                 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1669         default:
1670                 return 0;
1671         }
1672 }
1673
1674 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1675
1676 #define BPF_F_ATTACH_MASK \
1677         (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1678
1679 static int bpf_prog_attach(const union bpf_attr *attr)
1680 {
1681         enum bpf_prog_type ptype;
1682         struct bpf_prog *prog;
1683         int ret;
1684
1685         if (!capable(CAP_NET_ADMIN))
1686                 return -EPERM;
1687
1688         if (CHECK_ATTR(BPF_PROG_ATTACH))
1689                 return -EINVAL;
1690
1691         if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1692                 return -EINVAL;
1693
1694         switch (attr->attach_type) {
1695         case BPF_CGROUP_INET_INGRESS:
1696         case BPF_CGROUP_INET_EGRESS:
1697                 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1698                 break;
1699         case BPF_CGROUP_INET_SOCK_CREATE:
1700         case BPF_CGROUP_INET4_POST_BIND:
1701         case BPF_CGROUP_INET6_POST_BIND:
1702                 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1703                 break;
1704         case BPF_CGROUP_INET4_BIND:
1705         case BPF_CGROUP_INET6_BIND:
1706         case BPF_CGROUP_INET4_CONNECT:
1707         case BPF_CGROUP_INET6_CONNECT:
1708         case BPF_CGROUP_UDP4_SENDMSG:
1709         case BPF_CGROUP_UDP6_SENDMSG:
1710                 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1711                 break;
1712         case BPF_CGROUP_SOCK_OPS:
1713                 ptype = BPF_PROG_TYPE_SOCK_OPS;
1714                 break;
1715         case BPF_CGROUP_DEVICE:
1716                 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1717                 break;
1718         case BPF_SK_MSG_VERDICT:
1719                 ptype = BPF_PROG_TYPE_SK_MSG;
1720                 break;
1721         case BPF_SK_SKB_STREAM_PARSER:
1722         case BPF_SK_SKB_STREAM_VERDICT:
1723                 ptype = BPF_PROG_TYPE_SK_SKB;
1724                 break;
1725         case BPF_LIRC_MODE2:
1726                 ptype = BPF_PROG_TYPE_LIRC_MODE2;
1727                 break;
1728         case BPF_FLOW_DISSECTOR:
1729                 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1730                 break;
1731         default:
1732                 return -EINVAL;
1733         }
1734
1735         prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1736         if (IS_ERR(prog))
1737                 return PTR_ERR(prog);
1738
1739         if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1740                 bpf_prog_put(prog);
1741                 return -EINVAL;
1742         }
1743
1744         switch (ptype) {
1745         case BPF_PROG_TYPE_SK_SKB:
1746         case BPF_PROG_TYPE_SK_MSG:
1747                 ret = sock_map_get_from_fd(attr, prog);
1748                 break;
1749         case BPF_PROG_TYPE_LIRC_MODE2:
1750                 ret = lirc_prog_attach(attr, prog);
1751                 break;
1752         case BPF_PROG_TYPE_FLOW_DISSECTOR:
1753                 ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1754                 break;
1755         default:
1756                 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1757         }
1758
1759         if (ret)
1760                 bpf_prog_put(prog);
1761         return ret;
1762 }
1763
1764 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1765
1766 static int bpf_prog_detach(const union bpf_attr *attr)
1767 {
1768         enum bpf_prog_type ptype;
1769
1770         if (!capable(CAP_NET_ADMIN))
1771                 return -EPERM;
1772
1773         if (CHECK_ATTR(BPF_PROG_DETACH))
1774                 return -EINVAL;
1775
1776         switch (attr->attach_type) {
1777         case BPF_CGROUP_INET_INGRESS:
1778         case BPF_CGROUP_INET_EGRESS:
1779                 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1780                 break;
1781         case BPF_CGROUP_INET_SOCK_CREATE:
1782         case BPF_CGROUP_INET4_POST_BIND:
1783         case BPF_CGROUP_INET6_POST_BIND:
1784                 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1785                 break;
1786         case BPF_CGROUP_INET4_BIND:
1787         case BPF_CGROUP_INET6_BIND:
1788         case BPF_CGROUP_INET4_CONNECT:
1789         case BPF_CGROUP_INET6_CONNECT:
1790         case BPF_CGROUP_UDP4_SENDMSG:
1791         case BPF_CGROUP_UDP6_SENDMSG:
1792                 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1793                 break;
1794         case BPF_CGROUP_SOCK_OPS:
1795                 ptype = BPF_PROG_TYPE_SOCK_OPS;
1796                 break;
1797         case BPF_CGROUP_DEVICE:
1798                 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1799                 break;
1800         case BPF_SK_MSG_VERDICT:
1801                 return sock_map_get_from_fd(attr, NULL);
1802         case BPF_SK_SKB_STREAM_PARSER:
1803         case BPF_SK_SKB_STREAM_VERDICT:
1804                 return sock_map_get_from_fd(attr, NULL);
1805         case BPF_LIRC_MODE2:
1806                 return lirc_prog_detach(attr);
1807         case BPF_FLOW_DISSECTOR:
1808                 return skb_flow_dissector_bpf_prog_detach(attr);
1809         default:
1810                 return -EINVAL;
1811         }
1812
1813         return cgroup_bpf_prog_detach(attr, ptype);
1814 }
1815
1816 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
1817
1818 static int bpf_prog_query(const union bpf_attr *attr,
1819                           union bpf_attr __user *uattr)
1820 {
1821         if (!capable(CAP_NET_ADMIN))
1822                 return -EPERM;
1823         if (CHECK_ATTR(BPF_PROG_QUERY))
1824                 return -EINVAL;
1825         if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
1826                 return -EINVAL;
1827
1828         switch (attr->query.attach_type) {
1829         case BPF_CGROUP_INET_INGRESS:
1830         case BPF_CGROUP_INET_EGRESS:
1831         case BPF_CGROUP_INET_SOCK_CREATE:
1832         case BPF_CGROUP_INET4_BIND:
1833         case BPF_CGROUP_INET6_BIND:
1834         case BPF_CGROUP_INET4_POST_BIND:
1835         case BPF_CGROUP_INET6_POST_BIND:
1836         case BPF_CGROUP_INET4_CONNECT:
1837         case BPF_CGROUP_INET6_CONNECT:
1838         case BPF_CGROUP_UDP4_SENDMSG:
1839         case BPF_CGROUP_UDP6_SENDMSG:
1840         case BPF_CGROUP_SOCK_OPS:
1841         case BPF_CGROUP_DEVICE:
1842                 break;
1843         case BPF_LIRC_MODE2:
1844                 return lirc_prog_query(attr, uattr);
1845         default:
1846                 return -EINVAL;
1847         }
1848
1849         return cgroup_bpf_prog_query(attr, uattr);
1850 }
1851
1852 #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
1853
1854 static int bpf_prog_test_run(const union bpf_attr *attr,
1855                              union bpf_attr __user *uattr)
1856 {
1857         struct bpf_prog *prog;
1858         int ret = -ENOTSUPP;
1859
1860         if (!capable(CAP_SYS_ADMIN))
1861                 return -EPERM;
1862         if (CHECK_ATTR(BPF_PROG_TEST_RUN))
1863                 return -EINVAL;
1864
1865         prog = bpf_prog_get(attr->test.prog_fd);
1866         if (IS_ERR(prog))
1867                 return PTR_ERR(prog);
1868
1869         if (prog->aux->ops->test_run)
1870                 ret = prog->aux->ops->test_run(prog, attr, uattr);
1871
1872         bpf_prog_put(prog);
1873         return ret;
1874 }
1875
1876 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
1877
1878 static int bpf_obj_get_next_id(const union bpf_attr *attr,
1879                                union bpf_attr __user *uattr,
1880                                struct idr *idr,
1881                                spinlock_t *lock)
1882 {
1883         u32 next_id = attr->start_id;
1884         int err = 0;
1885
1886         if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
1887                 return -EINVAL;
1888
1889         if (!capable(CAP_SYS_ADMIN))
1890                 return -EPERM;
1891
1892         next_id++;
1893         spin_lock_bh(lock);
1894         if (!idr_get_next(idr, &next_id))
1895                 err = -ENOENT;
1896         spin_unlock_bh(lock);
1897
1898         if (!err)
1899                 err = put_user(next_id, &uattr->next_id);
1900
1901         return err;
1902 }
1903
1904 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
1905
1906 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
1907 {
1908         struct bpf_prog *prog;
1909         u32 id = attr->prog_id;
1910         int fd;
1911
1912         if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
1913                 return -EINVAL;
1914
1915         if (!capable(CAP_SYS_ADMIN))
1916                 return -EPERM;
1917
1918         spin_lock_bh(&prog_idr_lock);
1919         prog = idr_find(&prog_idr, id);
1920         if (prog)
1921                 prog = bpf_prog_inc_not_zero(prog);
1922         else
1923                 prog = ERR_PTR(-ENOENT);
1924         spin_unlock_bh(&prog_idr_lock);
1925
1926         if (IS_ERR(prog))
1927                 return PTR_ERR(prog);
1928
1929         fd = bpf_prog_new_fd(prog);
1930         if (fd < 0)
1931                 bpf_prog_put(prog);
1932
1933         return fd;
1934 }
1935
1936 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
1937
1938 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
1939 {
1940         struct bpf_map *map;
1941         u32 id = attr->map_id;
1942         int f_flags;
1943         int fd;
1944
1945         if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
1946             attr->open_flags & ~BPF_OBJ_FLAG_MASK)
1947                 return -EINVAL;
1948
1949         if (!capable(CAP_SYS_ADMIN))
1950                 return -EPERM;
1951
1952         f_flags = bpf_get_file_flag(attr->open_flags);
1953         if (f_flags < 0)
1954                 return f_flags;
1955
1956         spin_lock_bh(&map_idr_lock);
1957         map = idr_find(&map_idr, id);
1958         if (map)
1959                 map = bpf_map_inc_not_zero(map, true);
1960         else
1961                 map = ERR_PTR(-ENOENT);
1962         spin_unlock_bh(&map_idr_lock);
1963
1964         if (IS_ERR(map))
1965                 return PTR_ERR(map);
1966
1967         fd = bpf_map_new_fd(map, f_flags);
1968         if (fd < 0)
1969                 bpf_map_put(map);
1970
1971         return fd;
1972 }
1973
1974 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
1975                                               unsigned long addr)
1976 {
1977         int i;
1978
1979         for (i = 0; i < prog->aux->used_map_cnt; i++)
1980                 if (prog->aux->used_maps[i] == (void *)addr)
1981                         return prog->aux->used_maps[i];
1982         return NULL;
1983 }
1984
1985 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
1986 {
1987         const struct bpf_map *map;
1988         struct bpf_insn *insns;
1989         u64 imm;
1990         int i;
1991
1992         insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
1993                         GFP_USER);
1994         if (!insns)
1995                 return insns;
1996
1997         for (i = 0; i < prog->len; i++) {
1998                 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
1999                         insns[i].code = BPF_JMP | BPF_CALL;
2000                         insns[i].imm = BPF_FUNC_tail_call;
2001                         /* fall-through */
2002                 }
2003                 if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2004                     insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2005                         if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2006                                 insns[i].code = BPF_JMP | BPF_CALL;
2007                         if (!bpf_dump_raw_ok())
2008                                 insns[i].imm = 0;
2009                         continue;
2010                 }
2011
2012                 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2013                         continue;
2014
2015                 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2016                 map = bpf_map_from_imm(prog, imm);
2017                 if (map) {
2018                         insns[i].src_reg = BPF_PSEUDO_MAP_FD;
2019                         insns[i].imm = map->id;
2020                         insns[i + 1].imm = 0;
2021                         continue;
2022                 }
2023
2024                 if (!bpf_dump_raw_ok() &&
2025                     imm == (unsigned long)prog->aux) {
2026                         insns[i].imm = 0;
2027                         insns[i + 1].imm = 0;
2028                         continue;
2029                 }
2030         }
2031
2032         return insns;
2033 }
2034
2035 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
2036                                    const union bpf_attr *attr,
2037                                    union bpf_attr __user *uattr)
2038 {
2039         struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2040         struct bpf_prog_info info = {};
2041         u32 info_len = attr->info.info_len;
2042         char __user *uinsns;
2043         u32 ulen;
2044         int err;
2045
2046         err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2047         if (err)
2048                 return err;
2049         info_len = min_t(u32, sizeof(info), info_len);
2050
2051         if (copy_from_user(&info, uinfo, info_len))
2052                 return -EFAULT;
2053
2054         info.type = prog->type;
2055         info.id = prog->aux->id;
2056         info.load_time = prog->aux->load_time;
2057         info.created_by_uid = from_kuid_munged(current_user_ns(),
2058                                                prog->aux->user->uid);
2059         info.gpl_compatible = prog->gpl_compatible;
2060
2061         memcpy(info.tag, prog->tag, sizeof(prog->tag));
2062         memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2063
2064         ulen = info.nr_map_ids;
2065         info.nr_map_ids = prog->aux->used_map_cnt;
2066         ulen = min_t(u32, info.nr_map_ids, ulen);
2067         if (ulen) {
2068                 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2069                 u32 i;
2070
2071                 for (i = 0; i < ulen; i++)
2072                         if (put_user(prog->aux->used_maps[i]->id,
2073                                      &user_map_ids[i]))
2074                                 return -EFAULT;
2075         }
2076
2077         if (!capable(CAP_SYS_ADMIN)) {
2078                 info.jited_prog_len = 0;
2079                 info.xlated_prog_len = 0;
2080                 info.nr_jited_ksyms = 0;
2081                 info.nr_jited_func_lens = 0;
2082                 goto done;
2083         }
2084
2085         ulen = info.xlated_prog_len;
2086         info.xlated_prog_len = bpf_prog_insn_size(prog);
2087         if (info.xlated_prog_len && ulen) {
2088                 struct bpf_insn *insns_sanitized;
2089                 bool fault;
2090
2091                 if (prog->blinded && !bpf_dump_raw_ok()) {
2092                         info.xlated_prog_insns = 0;
2093                         goto done;
2094                 }
2095                 insns_sanitized = bpf_insn_prepare_dump(prog);
2096                 if (!insns_sanitized)
2097                         return -ENOMEM;
2098                 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2099                 ulen = min_t(u32, info.xlated_prog_len, ulen);
2100                 fault = copy_to_user(uinsns, insns_sanitized, ulen);
2101                 kfree(insns_sanitized);
2102                 if (fault)
2103                         return -EFAULT;
2104         }
2105
2106         if (bpf_prog_is_dev_bound(prog->aux)) {
2107                 err = bpf_prog_offload_info_fill(&info, prog);
2108                 if (err)
2109                         return err;
2110                 goto done;
2111         }
2112
2113         /* NOTE: the following code is supposed to be skipped for offload.
2114          * bpf_prog_offload_info_fill() is the place to fill similar fields
2115          * for offload.
2116          */
2117         ulen = info.jited_prog_len;
2118         if (prog->aux->func_cnt) {
2119                 u32 i;
2120
2121                 info.jited_prog_len = 0;
2122                 for (i = 0; i < prog->aux->func_cnt; i++)
2123                         info.jited_prog_len += prog->aux->func[i]->jited_len;
2124         } else {
2125                 info.jited_prog_len = prog->jited_len;
2126         }
2127
2128         if (info.jited_prog_len && ulen) {
2129                 if (bpf_dump_raw_ok()) {
2130                         uinsns = u64_to_user_ptr(info.jited_prog_insns);
2131                         ulen = min_t(u32, info.jited_prog_len, ulen);
2132
2133                         /* for multi-function programs, copy the JITed
2134                          * instructions for all the functions
2135                          */
2136                         if (prog->aux->func_cnt) {
2137                                 u32 len, free, i;
2138                                 u8 *img;
2139
2140                                 free = ulen;
2141                                 for (i = 0; i < prog->aux->func_cnt; i++) {
2142                                         len = prog->aux->func[i]->jited_len;
2143                                         len = min_t(u32, len, free);
2144                                         img = (u8 *) prog->aux->func[i]->bpf_func;
2145                                         if (copy_to_user(uinsns, img, len))
2146                                                 return -EFAULT;
2147                                         uinsns += len;
2148                                         free -= len;
2149                                         if (!free)
2150                                                 break;
2151                                 }
2152                         } else {
2153                                 if (copy_to_user(uinsns, prog->bpf_func, ulen))
2154                                         return -EFAULT;
2155                         }
2156                 } else {
2157                         info.jited_prog_insns = 0;
2158                 }
2159         }
2160
2161         ulen = info.nr_jited_ksyms;
2162         info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2163         if (info.nr_jited_ksyms && ulen) {
2164                 if (bpf_dump_raw_ok()) {
2165                         unsigned long ksym_addr;
2166                         u64 __user *user_ksyms;
2167                         u32 i;
2168
2169                         /* copy the address of the kernel symbol
2170                          * corresponding to each function
2171                          */
2172                         ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2173                         user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2174                         if (prog->aux->func_cnt) {
2175                                 for (i = 0; i < ulen; i++) {
2176                                         ksym_addr = (unsigned long)
2177                                                 prog->aux->func[i]->bpf_func;
2178                                         if (put_user((u64) ksym_addr,
2179                                                      &user_ksyms[i]))
2180                                                 return -EFAULT;
2181                                 }
2182                         } else {
2183                                 ksym_addr = (unsigned long) prog->bpf_func;
2184                                 if (put_user((u64) ksym_addr, &user_ksyms[0]))
2185                                         return -EFAULT;
2186                         }
2187                 } else {
2188                         info.jited_ksyms = 0;
2189                 }
2190         }
2191
2192         ulen = info.nr_jited_func_lens;
2193         info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2194         if (info.nr_jited_func_lens && ulen) {
2195                 if (bpf_dump_raw_ok()) {
2196                         u32 __user *user_lens;
2197                         u32 func_len, i;
2198
2199                         /* copy the JITed image lengths for each function */
2200                         ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2201                         user_lens = u64_to_user_ptr(info.jited_func_lens);
2202                         if (prog->aux->func_cnt) {
2203                                 for (i = 0; i < ulen; i++) {
2204                                         func_len =
2205                                                 prog->aux->func[i]->jited_len;
2206                                         if (put_user(func_len, &user_lens[i]))
2207                                                 return -EFAULT;
2208                                 }
2209                         } else {
2210                                 func_len = prog->jited_len;
2211                                 if (put_user(func_len, &user_lens[0]))
2212                                         return -EFAULT;
2213                         }
2214                 } else {
2215                         info.jited_func_lens = 0;
2216                 }
2217         }
2218
2219 done:
2220         if (copy_to_user(uinfo, &info, info_len) ||
2221             put_user(info_len, &uattr->info.info_len))
2222                 return -EFAULT;
2223
2224         return 0;
2225 }
2226
2227 static int bpf_map_get_info_by_fd(struct bpf_map *map,
2228                                   const union bpf_attr *attr,
2229                                   union bpf_attr __user *uattr)
2230 {
2231         struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2232         struct bpf_map_info info = {};
2233         u32 info_len = attr->info.info_len;
2234         int err;
2235
2236         err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2237         if (err)
2238                 return err;
2239         info_len = min_t(u32, sizeof(info), info_len);
2240
2241         info.type = map->map_type;
2242         info.id = map->id;
2243         info.key_size = map->key_size;
2244         info.value_size = map->value_size;
2245         info.max_entries = map->max_entries;
2246         info.map_flags = map->map_flags;
2247         memcpy(info.name, map->name, sizeof(map->name));
2248
2249         if (map->btf) {
2250                 info.btf_id = btf_id(map->btf);
2251                 info.btf_key_type_id = map->btf_key_type_id;
2252                 info.btf_value_type_id = map->btf_value_type_id;
2253         }
2254
2255         if (bpf_map_is_dev_bound(map)) {
2256                 err = bpf_map_offload_info_fill(&info, map);
2257                 if (err)
2258                         return err;
2259         }
2260
2261         if (copy_to_user(uinfo, &info, info_len) ||
2262             put_user(info_len, &uattr->info.info_len))
2263                 return -EFAULT;
2264
2265         return 0;
2266 }
2267
2268 static int bpf_btf_get_info_by_fd(struct btf *btf,
2269                                   const union bpf_attr *attr,
2270                                   union bpf_attr __user *uattr)
2271 {
2272         struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2273         u32 info_len = attr->info.info_len;
2274         int err;
2275
2276         err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2277         if (err)
2278                 return err;
2279
2280         return btf_get_info_by_fd(btf, attr, uattr);
2281 }
2282
2283 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2284
2285 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2286                                   union bpf_attr __user *uattr)
2287 {
2288         int ufd = attr->info.bpf_fd;
2289         struct fd f;
2290         int err;
2291
2292         if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2293                 return -EINVAL;
2294
2295         f = fdget(ufd);
2296         if (!f.file)
2297                 return -EBADFD;
2298
2299         if (f.file->f_op == &bpf_prog_fops)
2300                 err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
2301                                               uattr);
2302         else if (f.file->f_op == &bpf_map_fops)
2303                 err = bpf_map_get_info_by_fd(f.file->private_data, attr,
2304                                              uattr);
2305         else if (f.file->f_op == &btf_fops)
2306                 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
2307         else
2308                 err = -EINVAL;
2309
2310         fdput(f);
2311         return err;
2312 }
2313
2314 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2315
2316 static int bpf_btf_load(const union bpf_attr *attr)
2317 {
2318         if (CHECK_ATTR(BPF_BTF_LOAD))
2319                 return -EINVAL;
2320
2321         if (!capable(CAP_SYS_ADMIN))
2322                 return -EPERM;
2323
2324         return btf_new_fd(attr);
2325 }
2326
2327 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2328
2329 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2330 {
2331         if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2332                 return -EINVAL;
2333
2334         if (!capable(CAP_SYS_ADMIN))
2335                 return -EPERM;
2336
2337         return btf_get_fd_by_id(attr->btf_id);
2338 }
2339
2340 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2341                                     union bpf_attr __user *uattr,
2342                                     u32 prog_id, u32 fd_type,
2343                                     const char *buf, u64 probe_offset,
2344                                     u64 probe_addr)
2345 {
2346         char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2347         u32 len = buf ? strlen(buf) : 0, input_len;
2348         int err = 0;
2349
2350         if (put_user(len, &uattr->task_fd_query.buf_len))
2351                 return -EFAULT;
2352         input_len = attr->task_fd_query.buf_len;
2353         if (input_len && ubuf) {
2354                 if (!len) {
2355                         /* nothing to copy, just make ubuf NULL terminated */
2356                         char zero = '\0';
2357
2358                         if (put_user(zero, ubuf))
2359                                 return -EFAULT;
2360                 } else if (input_len >= len + 1) {
2361                         /* ubuf can hold the string with NULL terminator */
2362                         if (copy_to_user(ubuf, buf, len + 1))
2363                                 return -EFAULT;
2364                 } else {
2365                         /* ubuf cannot hold the string with NULL terminator,
2366                          * do a partial copy with NULL terminator.
2367                          */
2368                         char zero = '\0';
2369
2370                         err = -ENOSPC;
2371                         if (copy_to_user(ubuf, buf, input_len - 1))
2372                                 return -EFAULT;
2373                         if (put_user(zero, ubuf + input_len - 1))
2374                                 return -EFAULT;
2375                 }
2376         }
2377
2378         if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2379             put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2380             put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2381             put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2382                 return -EFAULT;
2383
2384         return err;
2385 }
2386
2387 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2388
2389 static int bpf_task_fd_query(const union bpf_attr *attr,
2390                              union bpf_attr __user *uattr)
2391 {
2392         pid_t pid = attr->task_fd_query.pid;
2393         u32 fd = attr->task_fd_query.fd;
2394         const struct perf_event *event;
2395         struct files_struct *files;
2396         struct task_struct *task;
2397         struct file *file;
2398         int err;
2399
2400         if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2401                 return -EINVAL;
2402
2403         if (!capable(CAP_SYS_ADMIN))
2404                 return -EPERM;
2405
2406         if (attr->task_fd_query.flags != 0)
2407                 return -EINVAL;
2408
2409         task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2410         if (!task)
2411                 return -ENOENT;
2412
2413         files = get_files_struct(task);
2414         put_task_struct(task);
2415         if (!files)
2416                 return -ENOENT;
2417
2418         err = 0;
2419         spin_lock(&files->file_lock);
2420         file = fcheck_files(files, fd);
2421         if (!file)
2422                 err = -EBADF;
2423         else
2424                 get_file(file);
2425         spin_unlock(&files->file_lock);
2426         put_files_struct(files);
2427
2428         if (err)
2429                 goto out;
2430
2431         if (file->f_op == &bpf_raw_tp_fops) {
2432                 struct bpf_raw_tracepoint *raw_tp = file->private_data;
2433                 struct bpf_raw_event_map *btp = raw_tp->btp;
2434
2435                 err = bpf_task_fd_query_copy(attr, uattr,
2436                                              raw_tp->prog->aux->id,
2437                                              BPF_FD_TYPE_RAW_TRACEPOINT,
2438                                              btp->tp->name, 0, 0);
2439                 goto put_file;
2440         }
2441
2442         event = perf_get_event(file);
2443         if (!IS_ERR(event)) {
2444                 u64 probe_offset, probe_addr;
2445                 u32 prog_id, fd_type;
2446                 const char *buf;
2447
2448                 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2449                                               &buf, &probe_offset,
2450                                               &probe_addr);
2451                 if (!err)
2452                         err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2453                                                      fd_type, buf,
2454                                                      probe_offset,
2455                                                      probe_addr);
2456                 goto put_file;
2457         }
2458
2459         err = -ENOTSUPP;
2460 put_file:
2461         fput(file);
2462 out:
2463         return err;
2464 }
2465
2466 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2467 {
2468         union bpf_attr attr = {};
2469         int err;
2470
2471         if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2472                 return -EPERM;
2473
2474         err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2475         if (err)
2476                 return err;
2477         size = min_t(u32, size, sizeof(attr));
2478
2479         /* copy attributes from user space, may be less than sizeof(bpf_attr) */
2480         if (copy_from_user(&attr, uattr, size) != 0)
2481                 return -EFAULT;
2482
2483         err = security_bpf(cmd, &attr, size);
2484         if (err < 0)
2485                 return err;
2486
2487         switch (cmd) {
2488         case BPF_MAP_CREATE:
2489                 err = map_create(&attr);
2490                 break;
2491         case BPF_MAP_LOOKUP_ELEM:
2492                 err = map_lookup_elem(&attr);
2493                 break;
2494         case BPF_MAP_UPDATE_ELEM:
2495                 err = map_update_elem(&attr);
2496                 break;
2497         case BPF_MAP_DELETE_ELEM:
2498                 err = map_delete_elem(&attr);
2499                 break;
2500         case BPF_MAP_GET_NEXT_KEY:
2501                 err = map_get_next_key(&attr);
2502                 break;
2503         case BPF_PROG_LOAD:
2504                 err = bpf_prog_load(&attr);
2505                 break;
2506         case BPF_OBJ_PIN:
2507                 err = bpf_obj_pin(&attr);
2508                 break;
2509         case BPF_OBJ_GET:
2510                 err = bpf_obj_get(&attr);
2511                 break;
2512         case BPF_PROG_ATTACH:
2513                 err = bpf_prog_attach(&attr);
2514                 break;
2515         case BPF_PROG_DETACH:
2516                 err = bpf_prog_detach(&attr);
2517                 break;
2518         case BPF_PROG_QUERY:
2519                 err = bpf_prog_query(&attr, uattr);
2520                 break;
2521         case BPF_PROG_TEST_RUN:
2522                 err = bpf_prog_test_run(&attr, uattr);
2523                 break;
2524         case BPF_PROG_GET_NEXT_ID:
2525                 err = bpf_obj_get_next_id(&attr, uattr,
2526                                           &prog_idr, &prog_idr_lock);
2527                 break;
2528         case BPF_MAP_GET_NEXT_ID:
2529                 err = bpf_obj_get_next_id(&attr, uattr,
2530                                           &map_idr, &map_idr_lock);
2531                 break;
2532         case BPF_PROG_GET_FD_BY_ID:
2533                 err = bpf_prog_get_fd_by_id(&attr);
2534                 break;
2535         case BPF_MAP_GET_FD_BY_ID:
2536                 err = bpf_map_get_fd_by_id(&attr);
2537                 break;
2538         case BPF_OBJ_GET_INFO_BY_FD:
2539                 err = bpf_obj_get_info_by_fd(&attr, uattr);
2540                 break;
2541         case BPF_RAW_TRACEPOINT_OPEN:
2542                 err = bpf_raw_tracepoint_open(&attr);
2543                 break;
2544         case BPF_BTF_LOAD:
2545                 err = bpf_btf_load(&attr);
2546                 break;
2547         case BPF_BTF_GET_FD_BY_ID:
2548                 err = bpf_btf_get_fd_by_id(&attr);
2549                 break;
2550         case BPF_TASK_FD_QUERY:
2551                 err = bpf_task_fd_query(&attr, uattr);
2552                 break;
2553         case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2554                 err = map_lookup_and_delete_elem(&attr);
2555                 break;
2556         default:
2557                 err = -EINVAL;
2558                 break;
2559         }
2560
2561         return err;
2562 }