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(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 really just want to fail instead of triggering OOM killer
 140          * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
 141          * which is used for lower order allocation requests.
 142          *
 143          * It has been observed that higher order allocation requests done by
 144          * vmalloc with __GFP_NORETRY being set might fail due to not trying
 145          * to reclaim memory from the page cache, thus we set
 146          * __GFP_RETRY_MAYFAIL to avoid such situations.
 147          */
 148
 149         const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
 150         void *area;
 151
 152         if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
 153                 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
 154                                     numa_node);
 155                 if (area != NULL)
 156                         return area;
 157         }
 158
 159         return __vmalloc_node_flags_caller(size, numa_node,
 160                                            GFP_KERNEL | __GFP_RETRY_MAYFAIL |
 161                                            flags, __builtin_return_address(0));
 162 }
 163
 164 void bpf_map_area_free(void *area)
 165 {
 166         kvfree(area);
 167 }
 168
 169 static u32 bpf_map_flags_retain_permanent(u32 flags)
 170 {
 171         /* Some map creation flags are not tied to the map object but
 172          * rather to the map fd instead, so they have no meaning upon
 173          * map object inspection since multiple file descriptors with
 174          * different (access) properties can exist here. Thus, given
 175          * this has zero meaning for the map itself, lets clear these
 176          * from here.
 177          */
 178         return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
 179 }
 180
 181 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 182 {
 183         map->map_type = attr->map_type;
 184         map->key_size = attr->key_size;
 185         map->value_size = attr->value_size;
 186         map->max_entries = attr->max_entries;
 187         map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
 188         map->numa_node = bpf_map_attr_numa_node(attr);
 189 }
 190
 191 int bpf_map_precharge_memlock(u32 pages)
 192 {
 193         struct user_struct *user = get_current_user();
 194         unsigned long memlock_limit, cur;
 195
 196         memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
 197         cur = atomic_long_read(&user->locked_vm);
 198         free_uid(user);
 199         if (cur + pages > memlock_limit)
 200                 return -EPERM;
 201         return 0;
 202 }
 203
 204 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
 205 {
 206         unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
 207
 208         if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
 209                 atomic_long_sub(pages, &user->locked_vm);
 210                 return -EPERM;
 211         }
 212         return 0;
 213 }
 214
 215 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
 216 {
 217         atomic_long_sub(pages, &user->locked_vm);
 218 }
 219
 220 static int bpf_map_init_memlock(struct bpf_map *map)
 221 {
 222         struct user_struct *user = get_current_user();
 223         int ret;
 224
 225         ret = bpf_charge_memlock(user, map->pages);
 226         if (ret) {
 227                 free_uid(user);
 228                 return ret;
 229         }
 230         map->user = user;
 231         return ret;
 232 }
 233
 234 static void bpf_map_release_memlock(struct bpf_map *map)
 235 {
 236         struct user_struct *user = map->user;
 237         bpf_uncharge_memlock(user, map->pages);
 238         free_uid(user);
 239 }
 240
 241 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
 242 {
 243         int ret;
 244
 245         ret = bpf_charge_memlock(map->user, pages);
 246         if (ret)
 247                 return ret;
 248         map->pages += pages;
 249         return ret;
 250 }
 251
 252 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
 253 {
 254         bpf_uncharge_memlock(map->user, pages);
 255         map->pages -= pages;
 256 }
 257
 258 static int bpf_map_alloc_id(struct bpf_map *map)
 259 {
 260         int id;
 261
 262         idr_preload(GFP_KERNEL);
 263         spin_lock_bh(&map_idr_lock);
 264         id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
 265         if (id > 0)
 266                 map->id = id;
 267         spin_unlock_bh(&map_idr_lock);
 268         idr_preload_end();
 269
 270         if (WARN_ON_ONCE(!id))
 271                 return -ENOSPC;
 272
 273         return id > 0 ? 0 : id;
 274 }
 275
 276 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
 277 {
 278         unsigned long flags;
 279
 280         /* Offloaded maps are removed from the IDR store when their device
 281          * disappears - even if someone holds an fd to them they are unusable,
 282          * the memory is gone, all ops will fail; they are simply waiting for
 283          * refcnt to drop to be freed.
 284          */
 285         if (!map->id)
 286                 return;
 287
 288         if (do_idr_lock)
 289                 spin_lock_irqsave(&map_idr_lock, flags);
 290         else
 291                 __acquire(&map_idr_lock);
 292
 293         idr_remove(&map_idr, map->id);
 294         map->id = 0;
 295
 296         if (do_idr_lock)
 297                 spin_unlock_irqrestore(&map_idr_lock, flags);
 298         else
 299                 __release(&map_idr_lock);
 300 }
 301
 302 /* called from workqueue */
 303 static void bpf_map_free_deferred(struct work_struct *work)
 304 {
 305         struct bpf_map *map = container_of(work, struct bpf_map, work);
 306
 307         bpf_map_release_memlock(map);
 308         security_bpf_map_free(map);
 309         /* implementation dependent freeing */
 310         map->ops->map_free(map);
 311 }
 312
 313 static void bpf_map_put_uref(struct bpf_map *map)
 314 {
 315         if (atomic_dec_and_test(&map->usercnt)) {
 316                 if (map->ops->map_release_uref)
 317                         map->ops->map_release_uref(map);
 318         }
 319 }
 320
 321 /* decrement map refcnt and schedule it for freeing via workqueue
 322  * (unrelying map implementation ops->map_free() might sleep)
 323  */
 324 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
 325 {
 326         if (atomic_dec_and_test(&map->refcnt)) {
 327                 /* bpf_map_free_id() must be called first */
 328                 bpf_map_free_id(map, do_idr_lock);
 329                 btf_put(map->btf);
 330                 INIT_WORK(&map->work, bpf_map_free_deferred);
 331                 schedule_work(&map->work);
 332         }
 333 }
 334
 335 void bpf_map_put(struct bpf_map *map)
 336 {
 337         __bpf_map_put(map, true);
 338 }
 339 EXPORT_SYMBOL_GPL(bpf_map_put);
 340
 341 void bpf_map_put_with_uref(struct bpf_map *map)
 342 {
 343         bpf_map_put_uref(map);
 344         bpf_map_put(map);
 345 }
 346
 347 static int bpf_map_release(struct inode *inode, struct file *filp)
 348 {
 349         struct bpf_map *map = filp->private_data;
 350
 351         if (map->ops->map_release)
 352                 map->ops->map_release(map, filp);
 353
 354         bpf_map_put_with_uref(map);
 355         return 0;
 356 }
 357
 358 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
 359 {
 360         fmode_t mode = f.file->f_mode;
 361
 362         /* Our file permissions may have been overridden by global
 363          * map permissions facing syscall side.
 364          */
 365         if (READ_ONCE(map->frozen))
 366                 mode &= ~FMODE_CAN_WRITE;
 367         return mode;
 368 }
 369
 370 #ifdef CONFIG_PROC_FS
 371 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 372 {
 373         const struct bpf_map *map = filp->private_data;
 374         const struct bpf_array *array;
 375         u32 owner_prog_type = 0;
 376         u32 owner_jited = 0;
 377
 378         if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
 379                 array = container_of(map, struct bpf_array, map);
 380                 owner_prog_type = array->owner_prog_type;
 381                 owner_jited = array->owner_jited;
 382         }
 383
 384         seq_printf(m,
 385                    "map_type:\t%u\n"
 386                    "key_size:\t%u\n"
 387                    "value_size:\t%u\n"
 388                    "max_entries:\t%u\n"
 389                    "map_flags:\t%#x\n"
 390                    "memlock:\t%llu\n"
 391                    "map_id:\t%u\n"
 392                    "frozen:\t%u\n",
 393                    map->map_type,
 394                    map->key_size,
 395                    map->value_size,
 396                    map->max_entries,
 397                    map->map_flags,
 398                    map->pages * 1ULL << PAGE_SHIFT,
 399                    map->id,
 400                    READ_ONCE(map->frozen));
 401
 402         if (owner_prog_type) {
 403                 seq_printf(m, "owner_prog_type:\t%u\n",
 404                            owner_prog_type);
 405                 seq_printf(m, "owner_jited:\t%u\n",
 406                            owner_jited);
 407         }
 408 }
 409 #endif
 410
 411 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
 412                               loff_t *ppos)
 413 {
 414         /* We need this handler such that alloc_file() enables
 415          * f_mode with FMODE_CAN_READ.
 416          */
 417         return -EINVAL;
 418 }
 419
 420 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
 421                                size_t siz, loff_t *ppos)
 422 {
 423         /* We need this handler such that alloc_file() enables
 424          * f_mode with FMODE_CAN_WRITE.
 425          */
 426         return -EINVAL;
 427 }
 428
 429 const struct file_operations bpf_map_fops = {
 430 #ifdef CONFIG_PROC_FS
 431         .show_fdinfo    = bpf_map_show_fdinfo,
 432 #endif
 433         .release        = bpf_map_release,
 434         .read           = bpf_dummy_read,
 435         .write          = bpf_dummy_write,
 436 };
 437
 438 int bpf_map_new_fd(struct bpf_map *map, int flags)
 439 {
 440         int ret;
 441
 442         ret = security_bpf_map(map, OPEN_FMODE(flags));
 443         if (ret < 0)
 444                 return ret;
 445
 446         return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
 447                                 flags | O_CLOEXEC);
 448 }
 449
 450 int bpf_get_file_flag(int flags)
 451 {
 452         if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
 453                 return -EINVAL;
 454         if (flags & BPF_F_RDONLY)
 455                 return O_RDONLY;
 456         if (flags & BPF_F_WRONLY)
 457                 return O_WRONLY;
 458         return O_RDWR;
 459 }
 460
 461 /* helper macro to check that unused fields 'union bpf_attr' are zero */
 462 #define CHECK_ATTR(CMD) \
 463         memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
 464                    sizeof(attr->CMD##_LAST_FIELD), 0, \
 465                    sizeof(*attr) - \
 466                    offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
 467                    sizeof(attr->CMD##_LAST_FIELD)) != NULL
 468
 469 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
 470  * Return 0 on success and < 0 on error.
 471  */
 472 static int bpf_obj_name_cpy(char *dst, const char *src)
 473 {
 474         const char *end = src + BPF_OBJ_NAME_LEN;
 475
 476         memset(dst, 0, BPF_OBJ_NAME_LEN);
 477         /* Copy all isalnum(), '_' and '.' chars. */
 478         while (src < end && *src) {
 479                 if (!isalnum(*src) &&
 480                     *src != '_' && *src != '.')
 481                         return -EINVAL;
 482                 *dst++ = *src++;
 483         }
 484
 485         /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
 486         if (src == end)
 487                 return -EINVAL;
 488
 489         return 0;
 490 }
 491
 492 int map_check_no_btf(const struct bpf_map *map,
 493                      const struct btf *btf,
 494                      const struct btf_type *key_type,
 495                      const struct btf_type *value_type)
 496 {
 497         return -ENOTSUPP;
 498 }
 499
 500 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 501                          u32 btf_key_id, u32 btf_value_id)
 502 {
 503         const struct btf_type *key_type, *value_type;
 504         u32 key_size, value_size;
 505         int ret = 0;
 506
 507         /* Some maps allow key to be unspecified. */
 508         if (btf_key_id) {
 509                 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
 510                 if (!key_type || key_size != map->key_size)
 511                         return -EINVAL;
 512         } else {
 513                 key_type = btf_type_by_id(btf, 0);
 514                 if (!map->ops->map_check_btf)
 515                         return -EINVAL;
 516         }
 517
 518         value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
 519         if (!value_type || value_size != map->value_size)
 520                 return -EINVAL;
 521
 522         map->spin_lock_off = btf_find_spin_lock(btf, value_type);
 523
 524         if (map_value_has_spin_lock(map)) {
 525                 if (map->map_flags & BPF_F_RDONLY_PROG)
 526                         return -EACCES;
 527                 if (map->map_type != BPF_MAP_TYPE_HASH &&
 528                     map->map_type != BPF_MAP_TYPE_ARRAY &&
 529                     map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE)
 530                         return -ENOTSUPP;
 531                 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
 532                     map->value_size) {
 533                         WARN_ONCE(1,
 534                                   "verifier bug spin_lock_off %d value_size %d\n",
 535                                   map->spin_lock_off, map->value_size);
 536                         return -EFAULT;
 537                 }
 538         }
 539
 540         if (map->ops->map_check_btf)
 541                 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
 542
 543         return ret;
 544 }
 545
 546 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
 547 /* called via syscall */
 548 static int map_create(union bpf_attr *attr)
 549 {
 550         int numa_node = bpf_map_attr_numa_node(attr);
 551         struct bpf_map *map;
 552         int f_flags;
 553         int err;
 554
 555         err = CHECK_ATTR(BPF_MAP_CREATE);
 556         if (err)
 557                 return -EINVAL;
 558
 559         f_flags = bpf_get_file_flag(attr->map_flags);
 560         if (f_flags < 0)
 561                 return f_flags;
 562
 563         if (numa_node != NUMA_NO_NODE &&
 564             ((unsigned int)numa_node >= nr_node_ids ||
 565              !node_online(numa_node)))
 566                 return -EINVAL;
 567
 568         /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
 569         map = find_and_alloc_map(attr);
 570         if (IS_ERR(map))
 571                 return PTR_ERR(map);
 572
 573         err = bpf_obj_name_cpy(map->name, attr->map_name);
 574         if (err)
 575                 goto free_map_nouncharge;
 576
 577         atomic_set(&map->refcnt, 1);
 578         atomic_set(&map->usercnt, 1);
 579
 580         if (attr->btf_key_type_id || attr->btf_value_type_id) {
 581                 struct btf *btf;
 582
 583                 if (!attr->btf_value_type_id) {
 584                         err = -EINVAL;
 585                         goto free_map_nouncharge;
 586                 }
 587
 588                 btf = btf_get_by_fd(attr->btf_fd);
 589                 if (IS_ERR(btf)) {
 590                         err = PTR_ERR(btf);
 591                         goto free_map_nouncharge;
 592                 }
 593
 594                 err = map_check_btf(map, btf, attr->btf_key_type_id,
 595                                     attr->btf_value_type_id);
 596                 if (err) {
 597                         btf_put(btf);
 598                         goto free_map_nouncharge;
 599                 }
 600
 601                 map->btf = btf;
 602                 map->btf_key_type_id = attr->btf_key_type_id;
 603                 map->btf_value_type_id = attr->btf_value_type_id;
 604         } else {
 605                 map->spin_lock_off = -EINVAL;
 606         }
 607
 608         err = security_bpf_map_alloc(map);
 609         if (err)
 610                 goto free_map_nouncharge;
 611
 612         err = bpf_map_init_memlock(map);
 613         if (err)
 614                 goto free_map_sec;
 615
 616         err = bpf_map_alloc_id(map);
 617         if (err)
 618                 goto free_map;
 619
 620         err = bpf_map_new_fd(map, f_flags);
 621         if (err < 0) {
 622                 /* failed to allocate fd.
 623                  * bpf_map_put_with_uref() is needed because the above
 624                  * bpf_map_alloc_id() has published the map
 625                  * to the userspace and the userspace may
 626                  * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
 627                  */
 628                 bpf_map_put_with_uref(map);
 629                 return err;
 630         }
 631
 632         return err;
 633
 634 free_map:
 635         bpf_map_release_memlock(map);
 636 free_map_sec:
 637         security_bpf_map_free(map);
 638 free_map_nouncharge:
 639         btf_put(map->btf);
 640         map->ops->map_free(map);
 641         return err;
 642 }
 643
 644 /* if error is returned, fd is released.
 645  * On success caller should complete fd access with matching fdput()
 646  */
 647 struct bpf_map *__bpf_map_get(struct fd f)
 648 {
 649         if (!f.file)
 650                 return ERR_PTR(-EBADF);
 651         if (f.file->f_op != &bpf_map_fops) {
 652                 fdput(f);
 653                 return ERR_PTR(-EINVAL);
 654         }
 655
 656         return f.file->private_data;
 657 }
 658
 659 /* prog's and map's refcnt limit */
 660 #define BPF_MAX_REFCNT 32768
 661
 662 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
 663 {
 664         if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
 665                 atomic_dec(&map->refcnt);
 666                 return ERR_PTR(-EBUSY);
 667         }
 668         if (uref)
 669                 atomic_inc(&map->usercnt);
 670         return map;
 671 }
 672 EXPORT_SYMBOL_GPL(bpf_map_inc);
 673
 674 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
 675 {
 676         struct fd f = fdget(ufd);
 677         struct bpf_map *map;
 678
 679         map = __bpf_map_get(f);
 680         if (IS_ERR(map))
 681                 return map;
 682
 683         map = bpf_map_inc(map, true);
 684         fdput(f);
 685
 686         return map;
 687 }
 688
 689 /* map_idr_lock should have been held */
 690 static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
 691                                             bool uref)
 692 {
 693         int refold;
 694
 695         refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
 696
 697         if (refold >= BPF_MAX_REFCNT) {
 698                 __bpf_map_put(map, false);
 699                 return ERR_PTR(-EBUSY);
 700         }
 701
 702         if (!refold)
 703                 return ERR_PTR(-ENOENT);
 704
 705         if (uref)
 706                 atomic_inc(&map->usercnt);
 707
 708         return map;
 709 }
 710
 711 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
 712 {
 713         return -ENOTSUPP;
 714 }
 715
 716 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
 717 {
 718         if (key_size)
 719                 return memdup_user(ukey, key_size);
 720
 721         if (ukey)
 722                 return ERR_PTR(-EINVAL);
 723
 724         return NULL;
 725 }
 726
 727 /* last field in 'union bpf_attr' used by this command */
 728 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
 729
 730 static int map_lookup_elem(union bpf_attr *attr)
 731 {
 732         void __user *ukey = u64_to_user_ptr(attr->key);
 733         void __user *uvalue = u64_to_user_ptr(attr->value);
 734         int ufd = attr->map_fd;
 735         struct bpf_map *map;
 736         void *key, *value, *ptr;
 737         u32 value_size;
 738         struct fd f;
 739         int err;
 740
 741         if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
 742                 return -EINVAL;
 743
 744         if (attr->flags & ~BPF_F_LOCK)
 745                 return -EINVAL;
 746
 747         f = fdget(ufd);
 748         map = __bpf_map_get(f);
 749         if (IS_ERR(map))
 750                 return PTR_ERR(map);
 751         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
 752                 err = -EPERM;
 753                 goto err_put;
 754         }
 755
 756         if ((attr->flags & BPF_F_LOCK) &&
 757             !map_value_has_spin_lock(map)) {
 758                 err = -EINVAL;
 759                 goto err_put;
 760         }
 761
 762         key = __bpf_copy_key(ukey, map->key_size);
 763         if (IS_ERR(key)) {
 764                 err = PTR_ERR(key);
 765                 goto err_put;
 766         }
 767
 768         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 769             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
 770             map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 771             map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 772                 value_size = round_up(map->value_size, 8) * num_possible_cpus();
 773         else if (IS_FD_MAP(map))
 774                 value_size = sizeof(u32);
 775         else
 776                 value_size = map->value_size;
 777
 778         err = -ENOMEM;
 779         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
 780         if (!value)
 781                 goto free_key;
 782
 783         if (bpf_map_is_dev_bound(map)) {
 784                 err = bpf_map_offload_lookup_elem(map, key, value);
 785                 goto done;
 786         }
 787
 788         preempt_disable();
 789         this_cpu_inc(bpf_prog_active);
 790         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 791             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 792                 err = bpf_percpu_hash_copy(map, key, value);
 793         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 794                 err = bpf_percpu_array_copy(map, key, value);
 795         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 796                 err = bpf_percpu_cgroup_storage_copy(map, key, value);
 797         } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
 798                 err = bpf_stackmap_copy(map, key, value);
 799         } else if (IS_FD_ARRAY(map)) {
 800                 err = bpf_fd_array_map_lookup_elem(map, key, value);
 801         } else if (IS_FD_HASH(map)) {
 802                 err = bpf_fd_htab_map_lookup_elem(map, key, value);
 803         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 804                 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
 805         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 806                    map->map_type == BPF_MAP_TYPE_STACK) {
 807                 err = map->ops->map_peek_elem(map, value);
 808         } else {
 809                 rcu_read_lock();
 810                 ptr = map->ops->map_lookup_elem(map, key);
 811                 if (IS_ERR(ptr)) {
 812                         err = PTR_ERR(ptr);
 813                 } else if (!ptr) {
 814                         err = -ENOENT;
 815                 } else {
 816                         err = 0;
 817                         if (attr->flags & BPF_F_LOCK)
 818                                 /* lock 'ptr' and copy everything but lock */
 819                                 copy_map_value_locked(map, value, ptr, true);
 820                         else
 821                                 copy_map_value(map, value, ptr);
 822                         /* mask lock, since value wasn't zero inited */
 823                         check_and_init_map_lock(map, value);
 824                 }
 825                 rcu_read_unlock();
 826         }
 827         this_cpu_dec(bpf_prog_active);
 828         preempt_enable();
 829
 830 done:
 831         if (err)
 832                 goto free_value;
 833
 834         err = -EFAULT;
 835         if (copy_to_user(uvalue, value, value_size) != 0)
 836                 goto free_value;
 837
 838         err = 0;
 839
 840 free_value:
 841         kfree(value);
 842 free_key:
 843         kfree(key);
 844 err_put:
 845         fdput(f);
 846         return err;
 847 }
 848
 849 static void maybe_wait_bpf_programs(struct bpf_map *map)
 850 {
 851         /* Wait for any running BPF programs to complete so that
 852          * userspace, when we return to it, knows that all programs
 853          * that could be running use the new map value.
 854          */
 855         if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
 856             map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
 857                 synchronize_rcu();
 858 }
 859
 860 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
 861
 862 static int map_update_elem(union bpf_attr *attr)
 863 {
 864         void __user *ukey = u64_to_user_ptr(attr->key);
 865         void __user *uvalue = u64_to_user_ptr(attr->value);
 866         int ufd = attr->map_fd;
 867         struct bpf_map *map;
 868         void *key, *value;
 869         u32 value_size;
 870         struct fd f;
 871         int err;
 872
 873         if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
 874                 return -EINVAL;
 875
 876         f = fdget(ufd);
 877         map = __bpf_map_get(f);
 878         if (IS_ERR(map))
 879                 return PTR_ERR(map);
 880         if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
 881                 err = -EPERM;
 882                 goto err_put;
 883         }
 884
 885         if ((attr->flags & BPF_F_LOCK) &&
 886             !map_value_has_spin_lock(map)) {
 887                 err = -EINVAL;
 888                 goto err_put;
 889         }
 890
 891         key = __bpf_copy_key(ukey, map->key_size);
 892         if (IS_ERR(key)) {
 893                 err = PTR_ERR(key);
 894                 goto err_put;
 895         }
 896
 897         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 898             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
 899             map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 900             map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 901                 value_size = round_up(map->value_size, 8) * num_possible_cpus();
 902         else
 903                 value_size = map->value_size;
 904
 905         err = -ENOMEM;
 906         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
 907         if (!value)
 908                 goto free_key;
 909
 910         err = -EFAULT;
 911         if (copy_from_user(value, uvalue, value_size) != 0)
 912                 goto free_value;
 913
 914         /* Need to create a kthread, thus must support schedule */
 915         if (bpf_map_is_dev_bound(map)) {
 916                 err = bpf_map_offload_update_elem(map, key, value, attr->flags);
 917                 goto out;
 918         } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
 919                    map->map_type == BPF_MAP_TYPE_SOCKHASH ||
 920                    map->map_type == BPF_MAP_TYPE_SOCKMAP) {
 921                 err = map->ops->map_update_elem(map, key, value, attr->flags);
 922                 goto out;
 923         }
 924
 925         /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
 926          * inside bpf map update or delete otherwise deadlocks are possible
 927          */
 928         preempt_disable();
 929         __this_cpu_inc(bpf_prog_active);
 930         if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 931             map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 932                 err = bpf_percpu_hash_update(map, key, value, attr->flags);
 933         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 934                 err = bpf_percpu_array_update(map, key, value, attr->flags);
 935         } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
 936                 err = bpf_percpu_cgroup_storage_update(map, key, value,
 937                                                        attr->flags);
 938         } else if (IS_FD_ARRAY(map)) {
 939                 rcu_read_lock();
 940                 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
 941                                                    attr->flags);
 942                 rcu_read_unlock();
 943         } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
 944                 rcu_read_lock();
 945                 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
 946                                                   attr->flags);
 947                 rcu_read_unlock();
 948         } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
 949                 /* rcu_read_lock() is not needed */
 950                 err = bpf_fd_reuseport_array_update_elem(map, key, value,
 951                                                          attr->flags);
 952         } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
 953                    map->map_type == BPF_MAP_TYPE_STACK) {
 954                 err = map->ops->map_push_elem(map, value, attr->flags);
 955         } else {
 956                 rcu_read_lock();
 957                 err = map->ops->map_update_elem(map, key, value, attr->flags);
 958                 rcu_read_unlock();
 959         }
 960         __this_cpu_dec(bpf_prog_active);
 961         preempt_enable();
 962         maybe_wait_bpf_programs(map);
 963 out:
 964 free_value:
 965         kfree(value);
 966 free_key:
 967         kfree(key);
 968 err_put:
 969         fdput(f);
 970         return err;
 971 }
 972
 973 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
 974
 975 static int map_delete_elem(union bpf_attr *attr)
 976 {
 977         void __user *ukey = u64_to_user_ptr(attr->key);
 978         int ufd = attr->map_fd;
 979         struct bpf_map *map;
 980         struct fd f;
 981         void *key;
 982         int err;
 983
 984         if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
 985                 return -EINVAL;
 986
 987         f = fdget(ufd);
 988         map = __bpf_map_get(f);
 989         if (IS_ERR(map))
 990                 return PTR_ERR(map);
 991         if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
 992                 err = -EPERM;
 993                 goto err_put;
 994         }
 995
 996         key = __bpf_copy_key(ukey, map->key_size);
 997         if (IS_ERR(key)) {
 998                 err = PTR_ERR(key);
 999                 goto err_put;
1000         }
1001
1002         if (bpf_map_is_dev_bound(map)) {
1003                 err = bpf_map_offload_delete_elem(map, key);
1004                 goto out;
1005         }
1006
1007         preempt_disable();
1008         __this_cpu_inc(bpf_prog_active);
1009         rcu_read_lock();
1010         err = map->ops->map_delete_elem(map, key);
1011         rcu_read_unlock();
1012         __this_cpu_dec(bpf_prog_active);
1013         preempt_enable();
1014         maybe_wait_bpf_programs(map);
1015 out:
1016         kfree(key);
1017 err_put:
1018         fdput(f);
1019         return err;
1020 }
1021
1022 /* last field in 'union bpf_attr' used by this command */
1023 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1024
1025 static int map_get_next_key(union bpf_attr *attr)
1026 {
1027         void __user *ukey = u64_to_user_ptr(attr->key);
1028         void __user *unext_key = u64_to_user_ptr(attr->next_key);
1029         int ufd = attr->map_fd;
1030         struct bpf_map *map;
1031         void *key, *next_key;
1032         struct fd f;
1033         int err;
1034
1035         if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1036                 return -EINVAL;
1037
1038         f = fdget(ufd);
1039         map = __bpf_map_get(f);
1040         if (IS_ERR(map))
1041                 return PTR_ERR(map);
1042         if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1043                 err = -EPERM;
1044                 goto err_put;
1045         }
1046
1047         if (ukey) {
1048                 key = __bpf_copy_key(ukey, map->key_size);
1049                 if (IS_ERR(key)) {
1050                         err = PTR_ERR(key);
1051                         goto err_put;
1052                 }
1053         } else {
1054                 key = NULL;
1055         }
1056
1057         err = -ENOMEM;
1058         next_key = kmalloc(map->key_size, GFP_USER);
1059         if (!next_key)
1060                 goto free_key;
1061
1062         if (bpf_map_is_dev_bound(map)) {
1063                 err = bpf_map_offload_get_next_key(map, key, next_key);
1064                 goto out;
1065         }
1066
1067         rcu_read_lock();
1068         err = map->ops->map_get_next_key(map, key, next_key);
1069         rcu_read_unlock();
1070 out:
1071         if (err)
1072                 goto free_next_key;
1073
1074         err = -EFAULT;
1075         if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1076                 goto free_next_key;
1077
1078         err = 0;
1079
1080 free_next_key:
1081         kfree(next_key);
1082 free_key:
1083         kfree(key);
1084 err_put:
1085         fdput(f);
1086         return err;
1087 }
1088
1089 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1090
1091 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1092 {
1093         void __user *ukey = u64_to_user_ptr(attr->key);
1094         void __user *uvalue = u64_to_user_ptr(attr->value);
1095         int ufd = attr->map_fd;
1096         struct bpf_map *map;
1097         void *key, *value;
1098         u32 value_size;
1099         struct fd f;
1100         int err;
1101
1102         if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1103                 return -EINVAL;
1104
1105         f = fdget(ufd);
1106         map = __bpf_map_get(f);
1107         if (IS_ERR(map))
1108                 return PTR_ERR(map);
1109         if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1110                 err = -EPERM;
1111                 goto err_put;
1112         }
1113
1114         key = __bpf_copy_key(ukey, map->key_size);
1115         if (IS_ERR(key)) {
1116                 err = PTR_ERR(key);
1117                 goto err_put;
1118         }
1119
1120         value_size = map->value_size;
1121
1122         err = -ENOMEM;
1123         value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1124         if (!value)
1125                 goto free_key;
1126
1127         if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1128             map->map_type == BPF_MAP_TYPE_STACK) {
1129                 err = map->ops->map_pop_elem(map, value);
1130         } else {
1131                 err = -ENOTSUPP;
1132         }
1133
1134         if (err)
1135                 goto free_value;
1136
1137         if (copy_to_user(uvalue, value, value_size) != 0)
1138                 goto free_value;
1139
1140         err = 0;
1141
1142 free_value:
1143         kfree(value);
1144 free_key:
1145         kfree(key);
1146 err_put:
1147         fdput(f);
1148         return err;
1149 }
1150
1151 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1152
1153 static int map_freeze(const union bpf_attr *attr)
1154 {
1155         int err = 0, ufd = attr->map_fd;
1156         struct bpf_map *map;
1157         struct fd f;
1158
1159         if (CHECK_ATTR(BPF_MAP_FREEZE))
1160                 return -EINVAL;
1161
1162         f = fdget(ufd);
1163         map = __bpf_map_get(f);
1164         if (IS_ERR(map))
1165                 return PTR_ERR(map);
1166         if (READ_ONCE(map->frozen)) {
1167                 err = -EBUSY;
1168                 goto err_put;
1169         }
1170         if (!capable(CAP_SYS_ADMIN)) {
1171                 err = -EPERM;
1172                 goto err_put;
1173         }
1174
1175         WRITE_ONCE(map->frozen, true);
1176 err_put:
1177         fdput(f);
1178         return err;
1179 }
1180
1181 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1182 #define BPF_PROG_TYPE(_id, _name) \
1183         [_id] = & _name ## _prog_ops,
1184 #define BPF_MAP_TYPE(_id, _ops)
1185 #include <linux/bpf_types.h>
1186 #undef BPF_PROG_TYPE
1187 #undef BPF_MAP_TYPE
1188 };
1189
1190 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1191 {
1192         const struct bpf_prog_ops *ops;
1193
1194         if (type >= ARRAY_SIZE(bpf_prog_types))
1195                 return -EINVAL;
1196         type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1197         ops = bpf_prog_types[type];
1198         if (!ops)
1199                 return -EINVAL;
1200
1201         if (!bpf_prog_is_dev_bound(prog->aux))
1202                 prog->aux->ops = ops;
1203         else
1204                 prog->aux->ops = &bpf_offload_prog_ops;
1205         prog->type = type;
1206         return 0;
1207 }
1208
1209 /* drop refcnt on maps used by eBPF program and free auxilary data */
1210 static void free_used_maps(struct bpf_prog_aux *aux)
1211 {
1212         enum bpf_cgroup_storage_type stype;
1213         int i;
1214
1215         for_each_cgroup_storage_type(stype) {
1216                 if (!aux->cgroup_storage[stype])
1217                         continue;
1218                 bpf_cgroup_storage_release(aux->prog,
1219                                            aux->cgroup_storage[stype]);
1220         }
1221
1222         for (i = 0; i < aux->used_map_cnt; i++)
1223                 bpf_map_put(aux->used_maps[i]);
1224
1225         kfree(aux->used_maps);
1226 }
1227
1228 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1229 {
1230         unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1231         unsigned long user_bufs;
1232
1233         if (user) {
1234                 user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1235                 if (user_bufs > memlock_limit) {
1236                         atomic_long_sub(pages, &user->locked_vm);
1237                         return -EPERM;
1238                 }
1239         }
1240
1241         return 0;
1242 }
1243
1244 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1245 {
1246         if (user)
1247                 atomic_long_sub(pages, &user->locked_vm);
1248 }
1249
1250 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1251 {
1252         struct user_struct *user = get_current_user();
1253         int ret;
1254
1255         ret = __bpf_prog_charge(user, prog->pages);
1256         if (ret) {
1257                 free_uid(user);
1258                 return ret;
1259         }
1260
1261         prog->aux->user = user;
1262         return 0;
1263 }
1264
1265 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1266 {
1267         struct user_struct *user = prog->aux->user;
1268
1269         __bpf_prog_uncharge(user, prog->pages);
1270         free_uid(user);
1271 }
1272
1273 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1274 {
1275         int id;
1276
1277         idr_preload(GFP_KERNEL);
1278         spin_lock_bh(&prog_idr_lock);
1279         id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1280         if (id > 0)
1281                 prog->aux->id = id;
1282         spin_unlock_bh(&prog_idr_lock);
1283         idr_preload_end();
1284
1285         /* id is in [1, INT_MAX) */
1286         if (WARN_ON_ONCE(!id))
1287                 return -ENOSPC;
1288
1289         return id > 0 ? 0 : id;
1290 }
1291
1292 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1293 {
1294         /* cBPF to eBPF migrations are currently not in the idr store.
1295          * Offloaded programs are removed from the store when their device
1296          * disappears - even if someone grabs an fd to them they are unusable,
1297          * simply waiting for refcnt to drop to be freed.
1298          */
1299         if (!prog->aux->id)
1300                 return;
1301
1302         if (do_idr_lock)
1303                 spin_lock_bh(&prog_idr_lock);
1304         else
1305                 __acquire(&prog_idr_lock);
1306
1307         idr_remove(&prog_idr, prog->aux->id);
1308         prog->aux->id = 0;
1309
1310         if (do_idr_lock)
1311                 spin_unlock_bh(&prog_idr_lock);
1312         else
1313                 __release(&prog_idr_lock);
1314 }
1315
1316 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1317 {
1318         struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1319
1320         free_used_maps(aux);
1321         bpf_prog_uncharge_memlock(aux->prog);
1322         security_bpf_prog_free(aux);
1323         bpf_prog_free(aux->prog);
1324 }
1325
1326 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1327 {
1328         if (atomic_dec_and_test(&prog->aux->refcnt)) {
1329                 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1330                 /* bpf_prog_free_id() must be called first */
1331                 bpf_prog_free_id(prog, do_idr_lock);
1332                 bpf_prog_kallsyms_del_all(prog);
1333                 btf_put(prog->aux->btf);
1334                 kvfree(prog->aux->func_info);
1335                 bpf_prog_free_linfo(prog);
1336
1337                 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1338         }
1339 }
1340
1341 void bpf_prog_put(struct bpf_prog *prog)
1342 {
1343         __bpf_prog_put(prog, true);
1344 }
1345 EXPORT_SYMBOL_GPL(bpf_prog_put);
1346
1347 static int bpf_prog_release(struct inode *inode, struct file *filp)
1348 {
1349         struct bpf_prog *prog = filp->private_data;
1350
1351         bpf_prog_put(prog);
1352         return 0;
1353 }
1354
1355 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1356                                struct bpf_prog_stats *stats)
1357 {
1358         u64 nsecs = 0, cnt = 0;
1359         int cpu;
1360
1361         for_each_possible_cpu(cpu) {
1362                 const struct bpf_prog_stats *st;
1363                 unsigned int start;
1364                 u64 tnsecs, tcnt;
1365
1366                 st = per_cpu_ptr(prog->aux->stats, cpu);
1367                 do {
1368                         start = u64_stats_fetch_begin_irq(&st->syncp);
1369                         tnsecs = st->nsecs;
1370                         tcnt = st->cnt;
1371                 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1372                 nsecs += tnsecs;
1373                 cnt += tcnt;
1374         }
1375         stats->nsecs = nsecs;
1376         stats->cnt = cnt;
1377 }
1378
1379 #ifdef CONFIG_PROC_FS
1380 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1381 {
1382         const struct bpf_prog *prog = filp->private_data;
1383         char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1384         struct bpf_prog_stats stats;
1385
1386         bpf_prog_get_stats(prog, &stats);
1387         bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1388         seq_printf(m,
1389                    "prog_type:\t%u\n"
1390                    "prog_jited:\t%u\n"
1391                    "prog_tag:\t%s\n"
1392                    "memlock:\t%llu\n"
1393                    "prog_id:\t%u\n"
1394                    "run_time_ns:\t%llu\n"
1395                    "run_cnt:\t%llu\n",
1396                    prog->type,
1397                    prog->jited,
1398                    prog_tag,
1399                    prog->pages * 1ULL << PAGE_SHIFT,
1400                    prog->aux->id,
1401                    stats.nsecs,
1402                    stats.cnt);
1403 }
1404 #endif
1405
1406 const struct file_operations bpf_prog_fops = {
1407 #ifdef CONFIG_PROC_FS
1408         .show_fdinfo    = bpf_prog_show_fdinfo,
1409 #endif
1410         .release        = bpf_prog_release,
1411         .read           = bpf_dummy_read,
1412         .write          = bpf_dummy_write,
1413 };
1414
1415 int bpf_prog_new_fd(struct bpf_prog *prog)
1416 {
1417         int ret;
1418
1419         ret = security_bpf_prog(prog);
1420         if (ret < 0)
1421                 return ret;
1422
1423         return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1424                                 O_RDWR | O_CLOEXEC);
1425 }
1426
1427 static struct bpf_prog *____bpf_prog_get(struct fd f)
1428 {
1429         if (!f.file)
1430                 return ERR_PTR(-EBADF);
1431         if (f.file->f_op != &bpf_prog_fops) {
1432                 fdput(f);
1433                 return ERR_PTR(-EINVAL);
1434         }
1435
1436         return f.file->private_data;
1437 }
1438
1439 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1440 {
1441         if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1442                 atomic_sub(i, &prog->aux->refcnt);
1443                 return ERR_PTR(-EBUSY);
1444         }
1445         return prog;
1446 }
1447 EXPORT_SYMBOL_GPL(bpf_prog_add);
1448
1449 void bpf_prog_sub(struct bpf_prog *prog, int i)
1450 {
1451         /* Only to be used for undoing previous bpf_prog_add() in some
1452          * error path. We still know that another entity in our call
1453          * path holds a reference to the program, thus atomic_sub() can
1454          * be safely used in such cases!
1455          */
1456         WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1457 }
1458 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1459
1460 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1461 {
1462         return bpf_prog_add(prog, 1);
1463 }
1464 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1465
1466 /* prog_idr_lock should have been held */
1467 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1468 {
1469         int refold;
1470
1471         refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1472
1473         if (refold >= BPF_MAX_REFCNT) {
1474                 __bpf_prog_put(prog, false);
1475                 return ERR_PTR(-EBUSY);
1476         }
1477
1478         if (!refold)
1479                 return ERR_PTR(-ENOENT);
1480
1481         return prog;
1482 }
1483 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1484
1485 bool bpf_prog_get_ok(struct bpf_prog *prog,
1486                             enum bpf_prog_type *attach_type, bool attach_drv)
1487 {
1488         /* not an attachment, just a refcount inc, always allow */
1489         if (!attach_type)
1490                 return true;
1491
1492         if (prog->type != *attach_type)
1493                 return false;
1494         if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1495                 return false;
1496
1497         return true;
1498 }
1499
1500 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1501                                        bool attach_drv)
1502 {
1503         struct fd f = fdget(ufd);
1504         struct bpf_prog *prog;
1505
1506         prog = ____bpf_prog_get(f);
1507         if (IS_ERR(prog))
1508                 return prog;
1509         if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1510                 prog = ERR_PTR(-EINVAL);
1511                 goto out;
1512         }
1513
1514         prog = bpf_prog_inc(prog);
1515 out:
1516         fdput(f);
1517         return prog;
1518 }
1519
1520 struct bpf_prog *bpf_prog_get(u32 ufd)
1521 {
1522         return __bpf_prog_get(ufd, NULL, false);
1523 }
1524
1525 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1526                                        bool attach_drv)
1527 {
1528         return __bpf_prog_get(ufd, &type, attach_drv);
1529 }
1530 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1531
1532 /* Initially all BPF programs could be loaded w/o specifying
1533  * expected_attach_type. Later for some of them specifying expected_attach_type
1534  * at load time became required so that program could be validated properly.
1535  * Programs of types that are allowed to be loaded both w/ and w/o (for
1536  * backward compatibility) expected_attach_type, should have the default attach
1537  * type assigned to expected_attach_type for the latter case, so that it can be
1538  * validated later at attach time.
1539  *
1540  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1541  * prog type requires it but has some attach types that have to be backward
1542  * compatible.
1543  */
1544 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1545 {
1546         switch (attr->prog_type) {
1547         case BPF_PROG_TYPE_CGROUP_SOCK:
1548                 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1549                  * exist so checking for non-zero is the way to go here.
1550                  */
1551                 if (!attr->expected_attach_type)
1552                         attr->expected_attach_type =
1553                                 BPF_CGROUP_INET_SOCK_CREATE;
1554                 break;
1555         }
1556 }
1557
1558 static int
1559 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1560                                 enum bpf_attach_type expected_attach_type)
1561 {
1562         switch (prog_type) {
1563         case BPF_PROG_TYPE_CGROUP_SOCK:
1564                 switch (expected_attach_type) {
1565                 case BPF_CGROUP_INET_SOCK_CREATE:
1566                 case BPF_CGROUP_INET4_POST_BIND:
1567                 case BPF_CGROUP_INET6_POST_BIND:
1568                         return 0;
1569                 default:
1570                         return -EINVAL;
1571                 }
1572         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1573                 switch (expected_attach_type) {
1574                 case BPF_CGROUP_INET4_BIND:
1575                 case BPF_CGROUP_INET6_BIND:
1576                 case BPF_CGROUP_INET4_CONNECT:
1577                 case BPF_CGROUP_INET6_CONNECT:
1578                 case BPF_CGROUP_UDP4_SENDMSG:
1579                 case BPF_CGROUP_UDP6_SENDMSG:
1580                         return 0;
1581                 default:
1582                         return -EINVAL;
1583                 }
1584         default:
1585                 return 0;
1586         }
1587 }
1588
1589 /* last field in 'union bpf_attr' used by this command */
1590 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt
1591
1592 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
1593 {
1594         enum bpf_prog_type type = attr->prog_type;
1595         struct bpf_prog *prog;
1596         int err;
1597         char license[128];
1598         bool is_gpl;
1599
1600         if (CHECK_ATTR(BPF_PROG_LOAD))
1601                 return -EINVAL;
1602
1603         if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | BPF_F_ANY_ALIGNMENT))
1604                 return -EINVAL;
1605
1606         if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
1607             (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
1608             !capable(CAP_SYS_ADMIN))
1609                 return -EPERM;
1610
1611         /* copy eBPF program license from user space */
1612         if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1613                               sizeof(license) - 1) < 0)
1614                 return -EFAULT;
1615         license[sizeof(license) - 1] = 0;
1616
1617         /* eBPF programs must be GPL compatible to use GPL-ed functions */
1618         is_gpl = license_is_gpl_compatible(license);
1619
1620         if (attr->insn_cnt == 0 ||
1621             attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
1622                 return -E2BIG;
1623         if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1624             type != BPF_PROG_TYPE_CGROUP_SKB &&
1625             !capable(CAP_SYS_ADMIN))
1626                 return -EPERM;
1627
1628         bpf_prog_load_fixup_attach_type(attr);
1629         if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1630                 return -EINVAL;
1631
1632         /* plain bpf_prog allocation */
1633         prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1634         if (!prog)
1635                 return -ENOMEM;
1636
1637         prog->expected_attach_type = attr->expected_attach_type;
1638
1639         prog->aux->offload_requested = !!attr->prog_ifindex;
1640
1641         err = security_bpf_prog_alloc(prog->aux);
1642         if (err)
1643                 goto free_prog_nouncharge;
1644
1645         err = bpf_prog_charge_memlock(prog);
1646         if (err)
1647                 goto free_prog_sec;
1648
1649         prog->len = attr->insn_cnt;
1650
1651         err = -EFAULT;
1652         if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1653                            bpf_prog_insn_size(prog)) != 0)
1654                 goto free_prog;
1655
1656         prog->orig_prog = NULL;
1657         prog->jited = 0;
1658
1659         atomic_set(&prog->aux->refcnt, 1);
1660         prog->gpl_compatible = is_gpl ? 1 : 0;
1661
1662         if (bpf_prog_is_dev_bound(prog->aux)) {
1663                 err = bpf_prog_offload_init(prog, attr);
1664                 if (err)
1665                         goto free_prog;
1666         }
1667
1668         /* find program type: socket_filter vs tracing_filter */
1669         err = find_prog_type(type, prog);
1670         if (err < 0)
1671                 goto free_prog;
1672
1673         prog->aux->load_time = ktime_get_boot_ns();
1674         err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1675         if (err)
1676                 goto free_prog;
1677
1678         /* run eBPF verifier */
1679         err = bpf_check(&prog, attr, uattr);
1680         if (err < 0)
1681                 goto free_used_maps;
1682
1683         prog = bpf_prog_select_runtime(prog, &err);
1684         if (err < 0)
1685                 goto free_used_maps;
1686
1687         err = bpf_prog_alloc_id(prog);
1688         if (err)
1689                 goto free_used_maps;
1690
1691         err = bpf_prog_new_fd(prog);
1692         if (err < 0) {
1693                 /* failed to allocate fd.
1694                  * bpf_prog_put() is needed because the above
1695                  * bpf_prog_alloc_id() has published the prog
1696                  * to the userspace and the userspace may
1697                  * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
1698                  */
1699                 bpf_prog_put(prog);
1700                 return err;
1701         }
1702
1703         bpf_prog_kallsyms_add(prog);
1704         perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
1705         return err;
1706
1707 free_used_maps:
1708         bpf_prog_free_linfo(prog);
1709         kvfree(prog->aux->func_info);
1710         btf_put(prog->aux->btf);
1711         bpf_prog_kallsyms_del_subprogs(prog);
1712         free_used_maps(prog->aux);
1713 free_prog:
1714         bpf_prog_uncharge_memlock(prog);
1715 free_prog_sec:
1716         security_bpf_prog_free(prog->aux);
1717 free_prog_nouncharge:
1718         bpf_prog_free(prog);
1719         return err;
1720 }
1721
1722 #define BPF_OBJ_LAST_FIELD file_flags
1723
1724 static int bpf_obj_pin(const union bpf_attr *attr)
1725 {
1726         if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1727                 return -EINVAL;
1728
1729         return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1730 }
1731
1732 static int bpf_obj_get(const union bpf_attr *attr)
1733 {
1734         if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1735             attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1736                 return -EINVAL;
1737
1738         return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1739                                 attr->file_flags);
1740 }
1741
1742 struct bpf_raw_tracepoint {
1743         struct bpf_raw_event_map *btp;
1744         struct bpf_prog *prog;
1745 };
1746
1747 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1748 {
1749         struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1750
1751         if (raw_tp->prog) {
1752                 bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1753                 bpf_prog_put(raw_tp->prog);
1754         }
1755         bpf_put_raw_tracepoint(raw_tp->btp);
1756         kfree(raw_tp);
1757         return 0;
1758 }
1759
1760 static const struct file_operations bpf_raw_tp_fops = {
1761         .release        = bpf_raw_tracepoint_release,
1762         .read           = bpf_dummy_read,
1763         .write          = bpf_dummy_write,
1764 };
1765
1766 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1767
1768 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1769 {
1770         struct bpf_raw_tracepoint *raw_tp;
1771         struct bpf_raw_event_map *btp;
1772         struct bpf_prog *prog;
1773         char tp_name[128];
1774         int tp_fd, err;
1775
1776         if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1777                               sizeof(tp_name) - 1) < 0)
1778                 return -EFAULT;
1779         tp_name[sizeof(tp_name) - 1] = 0;
1780
1781         btp = bpf_get_raw_tracepoint(tp_name);
1782         if (!btp)
1783                 return -ENOENT;
1784
1785         raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1786         if (!raw_tp) {
1787                 err = -ENOMEM;
1788                 goto out_put_btp;
1789         }
1790         raw_tp->btp = btp;
1791
1792         prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
1793                                  BPF_PROG_TYPE_RAW_TRACEPOINT);
1794         if (IS_ERR(prog)) {
1795                 err = PTR_ERR(prog);
1796                 goto out_free_tp;
1797         }
1798
1799         err = bpf_probe_register(raw_tp->btp, prog);
1800         if (err)
1801                 goto out_put_prog;
1802
1803         raw_tp->prog = prog;
1804         tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1805                                  O_CLOEXEC);
1806         if (tp_fd < 0) {
1807                 bpf_probe_unregister(raw_tp->btp, prog);
1808                 err = tp_fd;
1809                 goto out_put_prog;
1810         }
1811         return tp_fd;
1812
1813 out_put_prog:
1814         bpf_prog_put(prog);
1815 out_free_tp:
1816         kfree(raw_tp);
1817 out_put_btp:
1818         bpf_put_raw_tracepoint(btp);
1819         return err;
1820 }
1821
1822 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1823                                              enum bpf_attach_type attach_type)
1824 {
1825         switch (prog->type) {
1826         case BPF_PROG_TYPE_CGROUP_SOCK:
1827         case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1828                 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1829         default:
1830                 return 0;
1831         }
1832 }
1833
1834 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1835
1836 #define BPF_F_ATTACH_MASK \
1837         (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1838
1839 static int bpf_prog_attach(const union bpf_attr *attr)
1840 {
1841         enum bpf_prog_type ptype;
1842         struct bpf_prog *prog;
1843         int ret;
1844
1845         if (!capable(CAP_NET_ADMIN))
1846                 return -EPERM;
1847
1848         if (CHECK_ATTR(BPF_PROG_ATTACH))
1849                 return -EINVAL;
1850
1851         if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1852                 return -EINVAL;
1853
1854         switch (attr->attach_type) {
1855         case BPF_CGROUP_INET_INGRESS:
1856         case BPF_CGROUP_INET_EGRESS:
1857                 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1858                 break;
1859         case BPF_CGROUP_INET_SOCK_CREATE:
1860         case BPF_CGROUP_INET4_POST_BIND:
1861         case BPF_CGROUP_INET6_POST_BIND:
1862                 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1863                 break;
1864         case BPF_CGROUP_INET4_BIND:
1865         case BPF_CGROUP_INET6_BIND:
1866         case BPF_CGROUP_INET4_CONNECT:
1867         case BPF_CGROUP_INET6_CONNECT:
1868         case BPF_CGROUP_UDP4_SENDMSG:
1869         case BPF_CGROUP_UDP6_SENDMSG:
1870                 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1871                 break;
1872         case BPF_CGROUP_SOCK_OPS:
1873                 ptype = BPF_PROG_TYPE_SOCK_OPS;
1874                 break;
1875         case BPF_CGROUP_DEVICE:
1876                 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1877                 break;
1878         case BPF_SK_MSG_VERDICT:
1879                 ptype = BPF_PROG_TYPE_SK_MSG;
1880                 break;
1881         case BPF_SK_SKB_STREAM_PARSER:
1882         case BPF_SK_SKB_STREAM_VERDICT:
1883                 ptype = BPF_PROG_TYPE_SK_SKB;
1884                 break;
1885         case BPF_LIRC_MODE2:
1886                 ptype = BPF_PROG_TYPE_LIRC_MODE2;
1887                 break;
1888         case BPF_FLOW_DISSECTOR:
1889                 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1890                 break;
1891         default:
1892                 return -EINVAL;
1893         }
1894
1895         prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1896         if (IS_ERR(prog))
1897                 return PTR_ERR(prog);
1898
1899         if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1900                 bpf_prog_put(prog);
1901                 return -EINVAL;
1902         }
1903
1904         switch (ptype) {
1905         case BPF_PROG_TYPE_SK_SKB:
1906         case BPF_PROG_TYPE_SK_MSG:
1907                 ret = sock_map_get_from_fd(attr, prog);
1908                 break;
1909         case BPF_PROG_TYPE_LIRC_MODE2:
1910                 ret = lirc_prog_attach(attr, prog);
1911                 break;
1912         case BPF_PROG_TYPE_FLOW_DISSECTOR:
1913                 ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1914                 break;
1915         default:
1916                 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1917         }
1918
1919         if (ret)
1920                 bpf_prog_put(prog);
1921         return ret;
1922 }
1923
1924 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1925
1926 static int bpf_prog_detach(const union bpf_attr *attr)
1927 {
1928         enum bpf_prog_type ptype;
1929
1930         if (!capable(CAP_NET_ADMIN))
1931                 return -EPERM;
1932
1933         if (CHECK_ATTR(BPF_PROG_DETACH))
1934                 return -EINVAL;
1935
1936         switch (attr->attach_type) {
1937         case BPF_CGROUP_INET_INGRESS:
1938         case BPF_CGROUP_INET_EGRESS:
1939                 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1940                 break;
1941         case BPF_CGROUP_INET_SOCK_CREATE:
1942         case BPF_CGROUP_INET4_POST_BIND:
1943         case BPF_CGROUP_INET6_POST_BIND:
1944                 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1945                 break;
1946         case BPF_CGROUP_INET4_BIND:
1947         case BPF_CGROUP_INET6_BIND:
1948         case BPF_CGROUP_INET4_CONNECT:
1949         case BPF_CGROUP_INET6_CONNECT:
1950         case BPF_CGROUP_UDP4_SENDMSG:
1951         case BPF_CGROUP_UDP6_SENDMSG:
1952                 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1953                 break;
1954         case BPF_CGROUP_SOCK_OPS:
1955                 ptype = BPF_PROG_TYPE_SOCK_OPS;
1956                 break;
1957         case BPF_CGROUP_DEVICE:
1958                 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1959                 break;
1960         case BPF_SK_MSG_VERDICT:
1961                 return sock_map_get_from_fd(attr, NULL);
1962         case BPF_SK_SKB_STREAM_PARSER:
1963         case BPF_SK_SKB_STREAM_VERDICT:
1964                 return sock_map_get_from_fd(attr, NULL);
1965         case BPF_LIRC_MODE2:
1966                 return lirc_prog_detach(attr);
1967         case BPF_FLOW_DISSECTOR:
1968                 return skb_flow_dissector_bpf_prog_detach(attr);
1969         default:
1970                 return -EINVAL;
1971         }
1972
1973         return cgroup_bpf_prog_detach(attr, ptype);
1974 }
1975
1976 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
1977
1978 static int bpf_prog_query(const union bpf_attr *attr,
1979                           union bpf_attr __user *uattr)
1980 {
1981         if (!capable(CAP_NET_ADMIN))
1982                 return -EPERM;
1983         if (CHECK_ATTR(BPF_PROG_QUERY))
1984                 return -EINVAL;
1985         if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
1986                 return -EINVAL;
1987
1988         switch (attr->query.attach_type) {
1989         case BPF_CGROUP_INET_INGRESS:
1990         case BPF_CGROUP_INET_EGRESS:
1991         case BPF_CGROUP_INET_SOCK_CREATE:
1992         case BPF_CGROUP_INET4_BIND:
1993         case BPF_CGROUP_INET6_BIND:
1994         case BPF_CGROUP_INET4_POST_BIND:
1995         case BPF_CGROUP_INET6_POST_BIND:
1996         case BPF_CGROUP_INET4_CONNECT:
1997         case BPF_CGROUP_INET6_CONNECT:
1998         case BPF_CGROUP_UDP4_SENDMSG:
1999         case BPF_CGROUP_UDP6_SENDMSG:
2000         case BPF_CGROUP_SOCK_OPS:
2001         case BPF_CGROUP_DEVICE:
2002                 break;
2003         case BPF_LIRC_MODE2:
2004                 return lirc_prog_query(attr, uattr);
2005         default:
2006                 return -EINVAL;
2007         }
2008
2009         return cgroup_bpf_prog_query(attr, uattr);
2010 }
2011
2012 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
2013
2014 static int bpf_prog_test_run(const union bpf_attr *attr,
2015                              union bpf_attr __user *uattr)
2016 {
2017         struct bpf_prog *prog;
2018         int ret = -ENOTSUPP;
2019
2020         if (!capable(CAP_SYS_ADMIN))
2021                 return -EPERM;
2022         if (CHECK_ATTR(BPF_PROG_TEST_RUN))
2023                 return -EINVAL;
2024
2025         if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
2026             (!attr->test.ctx_size_in && attr->test.ctx_in))
2027                 return -EINVAL;
2028
2029         if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
2030             (!attr->test.ctx_size_out && attr->test.ctx_out))
2031                 return -EINVAL;
2032
2033         prog = bpf_prog_get(attr->test.prog_fd);
2034         if (IS_ERR(prog))
2035                 return PTR_ERR(prog);
2036
2037         if (prog->aux->ops->test_run)
2038                 ret = prog->aux->ops->test_run(prog, attr, uattr);
2039
2040         bpf_prog_put(prog);
2041         return ret;
2042 }
2043
2044 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
2045
2046 static int bpf_obj_get_next_id(const union bpf_attr *attr,
2047                                union bpf_attr __user *uattr,
2048                                struct idr *idr,
2049                                spinlock_t *lock)
2050 {
2051         u32 next_id = attr->start_id;
2052         int err = 0;
2053
2054         if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
2055                 return -EINVAL;
2056
2057         if (!capable(CAP_SYS_ADMIN))
2058                 return -EPERM;
2059
2060         next_id++;
2061         spin_lock_bh(lock);
2062         if (!idr_get_next(idr, &next_id))
2063                 err = -ENOENT;
2064         spin_unlock_bh(lock);
2065
2066         if (!err)
2067                 err = put_user(next_id, &uattr->next_id);
2068
2069         return err;
2070 }
2071
2072 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
2073
2074 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
2075 {
2076         struct bpf_prog *prog;
2077         u32 id = attr->prog_id;
2078         int fd;
2079
2080         if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
2081                 return -EINVAL;
2082
2083         if (!capable(CAP_SYS_ADMIN))
2084                 return -EPERM;
2085
2086         spin_lock_bh(&prog_idr_lock);
2087         prog = idr_find(&prog_idr, id);
2088         if (prog)
2089                 prog = bpf_prog_inc_not_zero(prog);
2090         else
2091                 prog = ERR_PTR(-ENOENT);
2092         spin_unlock_bh(&prog_idr_lock);
2093
2094         if (IS_ERR(prog))
2095                 return PTR_ERR(prog);
2096
2097         fd = bpf_prog_new_fd(prog);
2098         if (fd < 0)
2099                 bpf_prog_put(prog);
2100
2101         return fd;
2102 }
2103
2104 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
2105
2106 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
2107 {
2108         struct bpf_map *map;
2109         u32 id = attr->map_id;
2110         int f_flags;
2111         int fd;
2112
2113         if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
2114             attr->open_flags & ~BPF_OBJ_FLAG_MASK)
2115                 return -EINVAL;
2116
2117         if (!capable(CAP_SYS_ADMIN))
2118                 return -EPERM;
2119
2120         f_flags = bpf_get_file_flag(attr->open_flags);
2121         if (f_flags < 0)
2122                 return f_flags;
2123
2124         spin_lock_bh(&map_idr_lock);
2125         map = idr_find(&map_idr, id);
2126         if (map)
2127                 map = bpf_map_inc_not_zero(map, true);
2128         else
2129                 map = ERR_PTR(-ENOENT);
2130         spin_unlock_bh(&map_idr_lock);
2131
2132         if (IS_ERR(map))
2133                 return PTR_ERR(map);
2134
2135         fd = bpf_map_new_fd(map, f_flags);
2136         if (fd < 0)
2137                 bpf_map_put_with_uref(map);
2138
2139         return fd;
2140 }
2141
2142 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
2143                                               unsigned long addr, u32 *off,
2144                                               u32 *type)
2145 {
2146         const struct bpf_map *map;
2147         int i;
2148
2149         for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
2150                 map = prog->aux->used_maps[i];
2151                 if (map == (void *)addr) {
2152                         *type = BPF_PSEUDO_MAP_FD;
2153                         return map;
2154                 }
2155                 if (!map->ops->map_direct_value_meta)
2156                         continue;
2157                 if (!map->ops->map_direct_value_meta(map, addr, off)) {
2158                         *type = BPF_PSEUDO_MAP_VALUE;
2159                         return map;
2160                 }
2161         }
2162
2163         return NULL;
2164 }
2165
2166 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
2167 {
2168         const struct bpf_map *map;
2169         struct bpf_insn *insns;
2170         u32 off, type;
2171         u64 imm;
2172         int i;
2173
2174         insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
2175                         GFP_USER);
2176         if (!insns)
2177                 return insns;
2178
2179         for (i = 0; i < prog->len; i++) {
2180                 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
2181                         insns[i].code = BPF_JMP | BPF_CALL;
2182                         insns[i].imm = BPF_FUNC_tail_call;
2183                         /* fall-through */
2184                 }
2185                 if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2186                     insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2187                         if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2188                                 insns[i].code = BPF_JMP | BPF_CALL;
2189                         if (!bpf_dump_raw_ok())
2190                                 insns[i].imm = 0;
2191                         continue;
2192                 }
2193
2194                 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2195                         continue;
2196
2197                 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2198                 map = bpf_map_from_imm(prog, imm, &off, &type);
2199                 if (map) {
2200                         insns[i].src_reg = type;
2201                         insns[i].imm = map->id;
2202                         insns[i + 1].imm = off;
2203                         continue;
2204                 }
2205         }
2206
2207         return insns;
2208 }
2209
2210 static int set_info_rec_size(struct bpf_prog_info *info)
2211 {
2212         /*
2213          * Ensure info.*_rec_size is the same as kernel expected size
2214          *
2215          * or
2216          *
2217          * Only allow zero *_rec_size if both _rec_size and _cnt are
2218          * zero.  In this case, the kernel will set the expected
2219          * _rec_size back to the info.
2220          */
2221
2222         if ((info->nr_func_info || info->func_info_rec_size) &&
2223             info->func_info_rec_size != sizeof(struct bpf_func_info))
2224                 return -EINVAL;
2225
2226         if ((info->nr_line_info || info->line_info_rec_size) &&
2227             info->line_info_rec_size != sizeof(struct bpf_line_info))
2228                 return -EINVAL;
2229
2230         if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
2231             info->jited_line_info_rec_size != sizeof(__u64))
2232                 return -EINVAL;
2233
2234         info->func_info_rec_size = sizeof(struct bpf_func_info);
2235         info->line_info_rec_size = sizeof(struct bpf_line_info);
2236         info->jited_line_info_rec_size = sizeof(__u64);
2237
2238         return 0;
2239 }
2240
2241 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
2242                                    const union bpf_attr *attr,
2243                                    union bpf_attr __user *uattr)
2244 {
2245         struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2246         struct bpf_prog_info info = {};
2247         u32 info_len = attr->info.info_len;
2248         struct bpf_prog_stats stats;
2249         char __user *uinsns;
2250         u32 ulen;
2251         int err;
2252
2253         err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2254         if (err)
2255                 return err;
2256         info_len = min_t(u32, sizeof(info), info_len);
2257
2258         if (copy_from_user(&info, uinfo, info_len))
2259                 return -EFAULT;
2260
2261         info.type = prog->type;
2262         info.id = prog->aux->id;
2263         info.load_time = prog->aux->load_time;
2264         info.created_by_uid = from_kuid_munged(current_user_ns(),
2265                                                prog->aux->user->uid);
2266         info.gpl_compatible = prog->gpl_compatible;
2267
2268         memcpy(info.tag, prog->tag, sizeof(prog->tag));
2269         memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2270
2271         ulen = info.nr_map_ids;
2272         info.nr_map_ids = prog->aux->used_map_cnt;
2273         ulen = min_t(u32, info.nr_map_ids, ulen);
2274         if (ulen) {
2275                 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2276                 u32 i;
2277
2278                 for (i = 0; i < ulen; i++)
2279                         if (put_user(prog->aux->used_maps[i]->id,
2280                                      &user_map_ids[i]))
2281                                 return -EFAULT;
2282         }
2283
2284         err = set_info_rec_size(&info);
2285         if (err)
2286                 return err;
2287
2288         bpf_prog_get_stats(prog, &stats);
2289         info.run_time_ns = stats.nsecs;
2290         info.run_cnt = stats.cnt;
2291
2292         if (!capable(CAP_SYS_ADMIN)) {
2293                 info.jited_prog_len = 0;
2294                 info.xlated_prog_len = 0;
2295                 info.nr_jited_ksyms = 0;
2296                 info.nr_jited_func_lens = 0;
2297                 info.nr_func_info = 0;
2298                 info.nr_line_info = 0;
2299                 info.nr_jited_line_info = 0;
2300                 goto done;
2301         }
2302
2303         ulen = info.xlated_prog_len;
2304         info.xlated_prog_len = bpf_prog_insn_size(prog);
2305         if (info.xlated_prog_len && ulen) {
2306                 struct bpf_insn *insns_sanitized;
2307                 bool fault;
2308
2309                 if (prog->blinded && !bpf_dump_raw_ok()) {
2310                         info.xlated_prog_insns = 0;
2311                         goto done;
2312                 }
2313                 insns_sanitized = bpf_insn_prepare_dump(prog);
2314                 if (!insns_sanitized)
2315                         return -ENOMEM;
2316                 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2317                 ulen = min_t(u32, info.xlated_prog_len, ulen);
2318                 fault = copy_to_user(uinsns, insns_sanitized, ulen);
2319                 kfree(insns_sanitized);
2320                 if (fault)
2321                         return -EFAULT;
2322         }
2323
2324         if (bpf_prog_is_dev_bound(prog->aux)) {
2325                 err = bpf_prog_offload_info_fill(&info, prog);
2326                 if (err)
2327                         return err;
2328                 goto done;
2329         }
2330
2331         /* NOTE: the following code is supposed to be skipped for offload.
2332          * bpf_prog_offload_info_fill() is the place to fill similar fields
2333          * for offload.
2334          */
2335         ulen = info.jited_prog_len;
2336         if (prog->aux->func_cnt) {
2337                 u32 i;
2338
2339                 info.jited_prog_len = 0;
2340                 for (i = 0; i < prog->aux->func_cnt; i++)
2341                         info.jited_prog_len += prog->aux->func[i]->jited_len;
2342         } else {
2343                 info.jited_prog_len = prog->jited_len;
2344         }
2345
2346         if (info.jited_prog_len && ulen) {
2347                 if (bpf_dump_raw_ok()) {
2348                         uinsns = u64_to_user_ptr(info.jited_prog_insns);
2349                         ulen = min_t(u32, info.jited_prog_len, ulen);
2350
2351                         /* for multi-function programs, copy the JITed
2352                          * instructions for all the functions
2353                          */
2354                         if (prog->aux->func_cnt) {
2355                                 u32 len, free, i;
2356                                 u8 *img;
2357
2358                                 free = ulen;
2359                                 for (i = 0; i < prog->aux->func_cnt; i++) {
2360                                         len = prog->aux->func[i]->jited_len;
2361                                         len = min_t(u32, len, free);
2362                                         img = (u8 *) prog->aux->func[i]->bpf_func;
2363                                         if (copy_to_user(uinsns, img, len))
2364                                                 return -EFAULT;
2365                                         uinsns += len;
2366                                         free -= len;
2367                                         if (!free)
2368                                                 break;
2369                                 }
2370                         } else {
2371                                 if (copy_to_user(uinsns, prog->bpf_func, ulen))
2372                                         return -EFAULT;
2373                         }
2374                 } else {
2375                         info.jited_prog_insns = 0;
2376                 }
2377         }
2378
2379         ulen = info.nr_jited_ksyms;
2380         info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2381         if (ulen) {
2382                 if (bpf_dump_raw_ok()) {
2383                         unsigned long ksym_addr;
2384                         u64 __user *user_ksyms;
2385                         u32 i;
2386
2387                         /* copy the address of the kernel symbol
2388                          * corresponding to each function
2389                          */
2390                         ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2391                         user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2392                         if (prog->aux->func_cnt) {
2393                                 for (i = 0; i < ulen; i++) {
2394                                         ksym_addr = (unsigned long)
2395                                                 prog->aux->func[i]->bpf_func;
2396                                         if (put_user((u64) ksym_addr,
2397                                                      &user_ksyms[i]))
2398                                                 return -EFAULT;
2399                                 }
2400                         } else {
2401                                 ksym_addr = (unsigned long) prog->bpf_func;
2402                                 if (put_user((u64) ksym_addr, &user_ksyms[0]))
2403                                         return -EFAULT;
2404                         }
2405                 } else {
2406                         info.jited_ksyms = 0;
2407                 }
2408         }
2409
2410         ulen = info.nr_jited_func_lens;
2411         info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2412         if (ulen) {
2413                 if (bpf_dump_raw_ok()) {
2414                         u32 __user *user_lens;
2415                         u32 func_len, i;
2416
2417                         /* copy the JITed image lengths for each function */
2418                         ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2419                         user_lens = u64_to_user_ptr(info.jited_func_lens);
2420                         if (prog->aux->func_cnt) {
2421                                 for (i = 0; i < ulen; i++) {
2422                                         func_len =
2423                                                 prog->aux->func[i]->jited_len;
2424                                         if (put_user(func_len, &user_lens[i]))
2425                                                 return -EFAULT;
2426                                 }
2427                         } else {
2428                                 func_len = prog->jited_len;
2429                                 if (put_user(func_len, &user_lens[0]))
2430                                         return -EFAULT;
2431                         }
2432                 } else {
2433                         info.jited_func_lens = 0;
2434                 }
2435         }
2436
2437         if (prog->aux->btf)
2438                 info.btf_id = btf_id(prog->aux->btf);
2439
2440         ulen = info.nr_func_info;
2441         info.nr_func_info = prog->aux->func_info_cnt;
2442         if (info.nr_func_info && ulen) {
2443                 char __user *user_finfo;
2444
2445                 user_finfo = u64_to_user_ptr(info.func_info);
2446                 ulen = min_t(u32, info.nr_func_info, ulen);
2447                 if (copy_to_user(user_finfo, prog->aux->func_info,
2448                                  info.func_info_rec_size * ulen))
2449                         return -EFAULT;
2450         }
2451
2452         ulen = info.nr_line_info;
2453         info.nr_line_info = prog->aux->nr_linfo;
2454         if (info.nr_line_info && ulen) {
2455                 __u8 __user *user_linfo;
2456
2457                 user_linfo = u64_to_user_ptr(info.line_info);
2458                 ulen = min_t(u32, info.nr_line_info, ulen);
2459                 if (copy_to_user(user_linfo, prog->aux->linfo,
2460                                  info.line_info_rec_size * ulen))
2461                         return -EFAULT;
2462         }
2463
2464         ulen = info.nr_jited_line_info;
2465         if (prog->aux->jited_linfo)
2466                 info.nr_jited_line_info = prog->aux->nr_linfo;
2467         else
2468                 info.nr_jited_line_info = 0;
2469         if (info.nr_jited_line_info && ulen) {
2470                 if (bpf_dump_raw_ok()) {
2471                         __u64 __user *user_linfo;
2472                         u32 i;
2473
2474                         user_linfo = u64_to_user_ptr(info.jited_line_info);
2475                         ulen = min_t(u32, info.nr_jited_line_info, ulen);
2476                         for (i = 0; i < ulen; i++) {
2477                                 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
2478                                              &user_linfo[i]))
2479                                         return -EFAULT;
2480                         }
2481                 } else {
2482                         info.jited_line_info = 0;
2483                 }
2484         }
2485
2486         ulen = info.nr_prog_tags;
2487         info.nr_prog_tags = prog->aux->func_cnt ? : 1;
2488         if (ulen) {
2489                 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
2490                 u32 i;
2491
2492                 user_prog_tags = u64_to_user_ptr(info.prog_tags);
2493                 ulen = min_t(u32, info.nr_prog_tags, ulen);
2494                 if (prog->aux->func_cnt) {
2495                         for (i = 0; i < ulen; i++) {
2496                                 if (copy_to_user(user_prog_tags[i],
2497                                                  prog->aux->func[i]->tag,
2498                                                  BPF_TAG_SIZE))
2499                                         return -EFAULT;
2500                         }
2501                 } else {
2502                         if (copy_to_user(user_prog_tags[0],
2503                                          prog->tag, BPF_TAG_SIZE))
2504                                 return -EFAULT;
2505                 }
2506         }
2507
2508 done:
2509         if (copy_to_user(uinfo, &info, info_len) ||
2510             put_user(info_len, &uattr->info.info_len))
2511                 return -EFAULT;
2512
2513         return 0;
2514 }
2515
2516 static int bpf_map_get_info_by_fd(struct bpf_map *map,
2517                                   const union bpf_attr *attr,
2518                                   union bpf_attr __user *uattr)
2519 {
2520         struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2521         struct bpf_map_info info = {};
2522         u32 info_len = attr->info.info_len;
2523         int err;
2524
2525         err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2526         if (err)
2527                 return err;
2528         info_len = min_t(u32, sizeof(info), info_len);
2529
2530         info.type = map->map_type;
2531         info.id = map->id;
2532         info.key_size = map->key_size;
2533         info.value_size = map->value_size;
2534         info.max_entries = map->max_entries;
2535         info.map_flags = map->map_flags;
2536         memcpy(info.name, map->name, sizeof(map->name));
2537
2538         if (map->btf) {
2539                 info.btf_id = btf_id(map->btf);
2540                 info.btf_key_type_id = map->btf_key_type_id;
2541                 info.btf_value_type_id = map->btf_value_type_id;
2542         }
2543
2544         if (bpf_map_is_dev_bound(map)) {
2545                 err = bpf_map_offload_info_fill(&info, map);
2546                 if (err)
2547                         return err;
2548         }
2549
2550         if (copy_to_user(uinfo, &info, info_len) ||
2551             put_user(info_len, &uattr->info.info_len))
2552                 return -EFAULT;
2553
2554         return 0;
2555 }
2556
2557 static int bpf_btf_get_info_by_fd(struct btf *btf,
2558                                   const union bpf_attr *attr,
2559                                   union bpf_attr __user *uattr)
2560 {
2561         struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2562         u32 info_len = attr->info.info_len;
2563         int err;
2564
2565         err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2566         if (err)
2567                 return err;
2568
2569         return btf_get_info_by_fd(btf, attr, uattr);
2570 }
2571
2572 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2573
2574 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2575                                   union bpf_attr __user *uattr)
2576 {
2577         int ufd = attr->info.bpf_fd;
2578         struct fd f;
2579         int err;
2580
2581         if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2582                 return -EINVAL;
2583
2584         f = fdget(ufd);
2585         if (!f.file)
2586                 return -EBADFD;
2587
2588         if (f.file->f_op == &bpf_prog_fops)
2589                 err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
2590                                               uattr);
2591         else if (f.file->f_op == &bpf_map_fops)
2592                 err = bpf_map_get_info_by_fd(f.file->private_data, attr,
2593                                              uattr);
2594         else if (f.file->f_op == &btf_fops)
2595                 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
2596         else
2597                 err = -EINVAL;
2598
2599         fdput(f);
2600         return err;
2601 }
2602
2603 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2604
2605 static int bpf_btf_load(const union bpf_attr *attr)
2606 {
2607         if (CHECK_ATTR(BPF_BTF_LOAD))
2608                 return -EINVAL;
2609
2610         if (!capable(CAP_SYS_ADMIN))
2611                 return -EPERM;
2612
2613         return btf_new_fd(attr);
2614 }
2615
2616 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2617
2618 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2619 {
2620         if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2621                 return -EINVAL;
2622
2623         if (!capable(CAP_SYS_ADMIN))
2624                 return -EPERM;
2625
2626         return btf_get_fd_by_id(attr->btf_id);
2627 }
2628
2629 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2630                                     union bpf_attr __user *uattr,
2631                                     u32 prog_id, u32 fd_type,
2632                                     const char *buf, u64 probe_offset,
2633                                     u64 probe_addr)
2634 {
2635         char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2636         u32 len = buf ? strlen(buf) : 0, input_len;
2637         int err = 0;
2638
2639         if (put_user(len, &uattr->task_fd_query.buf_len))
2640                 return -EFAULT;
2641         input_len = attr->task_fd_query.buf_len;
2642         if (input_len && ubuf) {
2643                 if (!len) {
2644                         /* nothing to copy, just make ubuf NULL terminated */
2645                         char zero = '\0';
2646
2647                         if (put_user(zero, ubuf))
2648                                 return -EFAULT;
2649                 } else if (input_len >= len + 1) {
2650                         /* ubuf can hold the string with NULL terminator */
2651                         if (copy_to_user(ubuf, buf, len + 1))
2652                                 return -EFAULT;
2653                 } else {
2654                         /* ubuf cannot hold the string with NULL terminator,
2655                          * do a partial copy with NULL terminator.
2656                          */
2657                         char zero = '\0';
2658
2659                         err = -ENOSPC;
2660                         if (copy_to_user(ubuf, buf, input_len - 1))
2661                                 return -EFAULT;
2662                         if (put_user(zero, ubuf + input_len - 1))
2663                                 return -EFAULT;
2664                 }
2665         }
2666
2667         if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2668             put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2669             put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2670             put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2671                 return -EFAULT;
2672
2673         return err;
2674 }
2675
2676 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2677
2678 static int bpf_task_fd_query(const union bpf_attr *attr,
2679                              union bpf_attr __user *uattr)
2680 {
2681         pid_t pid = attr->task_fd_query.pid;
2682         u32 fd = attr->task_fd_query.fd;
2683         const struct perf_event *event;
2684         struct files_struct *files;
2685         struct task_struct *task;
2686         struct file *file;
2687         int err;
2688
2689         if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2690                 return -EINVAL;
2691
2692         if (!capable(CAP_SYS_ADMIN))
2693                 return -EPERM;
2694
2695         if (attr->task_fd_query.flags != 0)
2696                 return -EINVAL;
2697
2698         task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2699         if (!task)
2700                 return -ENOENT;
2701
2702         files = get_files_struct(task);
2703         put_task_struct(task);
2704         if (!files)
2705                 return -ENOENT;
2706
2707         err = 0;
2708         spin_lock(&files->file_lock);
2709         file = fcheck_files(files, fd);
2710         if (!file)
2711                 err = -EBADF;
2712         else
2713                 get_file(file);
2714         spin_unlock(&files->file_lock);
2715         put_files_struct(files);
2716
2717         if (err)
2718                 goto out;
2719
2720         if (file->f_op == &bpf_raw_tp_fops) {
2721                 struct bpf_raw_tracepoint *raw_tp = file->private_data;
2722                 struct bpf_raw_event_map *btp = raw_tp->btp;
2723
2724                 err = bpf_task_fd_query_copy(attr, uattr,
2725                                              raw_tp->prog->aux->id,
2726                                              BPF_FD_TYPE_RAW_TRACEPOINT,
2727                                              btp->tp->name, 0, 0);
2728                 goto put_file;
2729         }
2730
2731         event = perf_get_event(file);
2732         if (!IS_ERR(event)) {
2733                 u64 probe_offset, probe_addr;
2734                 u32 prog_id, fd_type;
2735                 const char *buf;
2736
2737                 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2738                                               &buf, &probe_offset,
2739                                               &probe_addr);
2740                 if (!err)
2741                         err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2742                                                      fd_type, buf,
2743                                                      probe_offset,
2744                                                      probe_addr);
2745                 goto put_file;
2746         }
2747
2748         err = -ENOTSUPP;
2749 put_file:
2750         fput(file);
2751 out:
2752         return err;
2753 }
2754
2755 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2756 {
2757         union bpf_attr attr = {};
2758         int err;
2759
2760         if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2761                 return -EPERM;
2762
2763         err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2764         if (err)
2765                 return err;
2766         size = min_t(u32, size, sizeof(attr));
2767
2768         /* copy attributes from user space, may be less than sizeof(bpf_attr) */
2769         if (copy_from_user(&attr, uattr, size) != 0)
2770                 return -EFAULT;
2771
2772         err = security_bpf(cmd, &attr, size);
2773         if (err < 0)
2774                 return err;
2775
2776         switch (cmd) {
2777         case BPF_MAP_CREATE:
2778                 err = map_create(&attr);
2779                 break;
2780         case BPF_MAP_LOOKUP_ELEM:
2781                 err = map_lookup_elem(&attr);
2782                 break;
2783         case BPF_MAP_UPDATE_ELEM:
2784                 err = map_update_elem(&attr);
2785                 break;
2786         case BPF_MAP_DELETE_ELEM:
2787                 err = map_delete_elem(&attr);
2788                 break;
2789         case BPF_MAP_GET_NEXT_KEY:
2790                 err = map_get_next_key(&attr);
2791                 break;
2792         case BPF_MAP_FREEZE:
2793                 err = map_freeze(&attr);
2794                 break;
2795         case BPF_PROG_LOAD:
2796                 err = bpf_prog_load(&attr, uattr);
2797                 break;
2798         case BPF_OBJ_PIN:
2799                 err = bpf_obj_pin(&attr);
2800                 break;
2801         case BPF_OBJ_GET:
2802                 err = bpf_obj_get(&attr);
2803                 break;
2804         case BPF_PROG_ATTACH:
2805                 err = bpf_prog_attach(&attr);
2806                 break;
2807         case BPF_PROG_DETACH:
2808                 err = bpf_prog_detach(&attr);
2809                 break;
2810         case BPF_PROG_QUERY:
2811                 err = bpf_prog_query(&attr, uattr);
2812                 break;
2813         case BPF_PROG_TEST_RUN:
2814                 err = bpf_prog_test_run(&attr, uattr);
2815                 break;
2816         case BPF_PROG_GET_NEXT_ID:
2817                 err = bpf_obj_get_next_id(&attr, uattr,
2818                                           &prog_idr, &prog_idr_lock);
2819                 break;
2820         case BPF_MAP_GET_NEXT_ID:
2821                 err = bpf_obj_get_next_id(&attr, uattr,
2822                                           &map_idr, &map_idr_lock);
2823                 break;
2824         case BPF_PROG_GET_FD_BY_ID:
2825                 err = bpf_prog_get_fd_by_id(&attr);
2826                 break;
2827         case BPF_MAP_GET_FD_BY_ID:
2828                 err = bpf_map_get_fd_by_id(&attr);
2829                 break;
2830         case BPF_OBJ_GET_INFO_BY_FD:
2831                 err = bpf_obj_get_info_by_fd(&attr, uattr);
2832                 break;
2833         case BPF_RAW_TRACEPOINT_OPEN:
2834                 err = bpf_raw_tracepoint_open(&attr);
2835                 break;
2836         case BPF_BTF_LOAD:
2837                 err = bpf_btf_load(&attr);
2838                 break;
2839         case BPF_BTF_GET_FD_BY_ID:
2840                 err = bpf_btf_get_fd_by_id(&attr);
2841                 break;
2842         case BPF_TASK_FD_QUERY:
2843                 err = bpf_task_fd_query(&attr, uattr);
2844                 break;
2845         case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2846                 err = map_lookup_and_delete_elem(&attr);
2847                 break;
2848         default:
2849                 err = -EINVAL;
2850                 break;
2851         }
2852
2853         return err;
2854 }