| 1 | |
| 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/syscalls.h>
|
| 15 | #include <linux/slab.h>
|
| 16 | #include <linux/sched/signal.h>
|
| 17 | #include <linux/vmalloc.h>
|
| 18 | #include <linux/mmzone.h>
|
| 19 | #include <linux/anon_inodes.h>
|
| 20 | #include <linux/file.h>
|
| 21 | #include <linux/license.h>
|
| 22 | #include <linux/filter.h>
|
| 23 | #include <linux/version.h>
|
| 24 | #include <linux/kernel.h>
|
| 25 | #include <linux/idr.h>
|
| 26 |
|
| 27 | #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
|
| 28 | (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
|
| 29 | (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
|
| 30 | (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
|
| 31 | #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
|
| 32 | #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
|
| 33 |
|
| 34 | DEFINE_PER_CPU(int, bpf_prog_active);
|
| 35 | static DEFINE_IDR(prog_idr);
|
| 36 | static DEFINE_SPINLOCK(prog_idr_lock);
|
| 37 | static DEFINE_IDR(map_idr);
|
| 38 | static DEFINE_SPINLOCK(map_idr_lock);
|
| 39 |
|
| 40 | int sysctl_unprivileged_bpf_disabled __read_mostly;
|
| 41 |
|
| 42 | static const struct bpf_map_ops * const bpf_map_types[] = {
|
| 43 | #define BPF_PROG_TYPE(_id, _ops)
|
| 44 | #define BPF_MAP_TYPE(_id, _ops) \
|
| 45 | [_id] = &_ops,
|
| 46 | #include <linux/bpf_types.h>
|
| 47 | #undef BPF_PROG_TYPE
|
| 48 | #undef BPF_MAP_TYPE
|
| 49 | };
|
| 50 |
|
| 51 | static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
|
| 52 | {
|
| 53 | struct bpf_map *map;
|
| 54 |
|
| 55 | if (attr->map_type >= ARRAY_SIZE(bpf_map_types) ||
|
| 56 | !bpf_map_types[attr->map_type])
|
| 57 | return ERR_PTR(-EINVAL);
|
| 58 |
|
| 59 | map = bpf_map_types[attr->map_type]->map_alloc(attr);
|
| 60 | if (IS_ERR(map))
|
| 61 | return map;
|
| 62 | map->ops = bpf_map_types[attr->map_type];
|
| 63 | map->map_type = attr->map_type;
|
| 64 | return map;
|
| 65 | }
|
| 66 |
|
| 67 | void *bpf_map_area_alloc(size_t size)
|
| 68 | {
|
| 69 | |
| 70 | * trigger under memory pressure as we really just want to
|
| 71 | * fail instead.
|
| 72 |
|
| 73 | const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
|
| 74 | void *area;
|
| 75 |
|
| 76 | if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
|
| 77 | area = kmalloc(size, GFP_USER | flags);
|
| 78 | if (area != NULL)
|
| 79 | return area;
|
| 80 | }
|
| 81 |
|
| 82 | return __vmalloc(size, GFP_KERNEL | flags, PAGE_KERNEL);
|
| 83 | }
|
| 84 |
|
| 85 | void bpf_map_area_free(void *area)
|
| 86 | {
|
| 87 | kvfree(area);
|
| 88 | }
|
| 89 |
|
| 90 | int bpf_map_precharge_memlock(u32 pages)
|
| 91 | {
|
| 92 | struct user_struct *user = get_current_user();
|
| 93 | unsigned long memlock_limit, cur;
|
| 94 |
|
| 95 | memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
|
| 96 | cur = atomic_long_read(&user->locked_vm);
|
| 97 | free_uid(user);
|
| 98 | if (cur + pages > memlock_limit)
|
| 99 | return -EPERM;
|
| 100 | return 0;
|
| 101 | }
|
| 102 |
|
| 103 | static int bpf_map_charge_memlock(struct bpf_map *map)
|
| 104 | {
|
| 105 | struct user_struct *user = get_current_user();
|
| 106 | unsigned long memlock_limit;
|
| 107 |
|
| 108 | memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
|
| 109 |
|
| 110 | atomic_long_add(map->pages, &user->locked_vm);
|
| 111 |
|
| 112 | if (atomic_long_read(&user->locked_vm) > memlock_limit) {
|
| 113 | atomic_long_sub(map->pages, &user->locked_vm);
|
| 114 | free_uid(user);
|
| 115 | return -EPERM;
|
| 116 | }
|
| 117 | map->user = user;
|
| 118 | return 0;
|
| 119 | }
|
| 120 |
|
| 121 | static void bpf_map_uncharge_memlock(struct bpf_map *map)
|
| 122 | {
|
| 123 | struct user_struct *user = map->user;
|
| 124 |
|
| 125 | atomic_long_sub(map->pages, &user->locked_vm);
|
| 126 | free_uid(user);
|
| 127 | }
|
| 128 |
|
| 129 | static int bpf_map_alloc_id(struct bpf_map *map)
|
| 130 | {
|
| 131 | int id;
|
| 132 |
|
| 133 | spin_lock_bh(&map_idr_lock);
|
| 134 | id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
|
| 135 | if (id > 0)
|
| 136 | map->id = id;
|
| 137 | spin_unlock_bh(&map_idr_lock);
|
| 138 |
|
| 139 | if (WARN_ON_ONCE(!id))
|
| 140 | return -ENOSPC;
|
| 141 |
|
| 142 | return id > 0 ? 0 : id;
|
| 143 | }
|
| 144 |
|
| 145 | static void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
|
| 146 | {
|
| 147 | if (do_idr_lock)
|
| 148 | spin_lock_bh(&map_idr_lock);
|
| 149 | else
|
| 150 | __acquire(&map_idr_lock);
|
| 151 |
|
| 152 | idr_remove(&map_idr, map->id);
|
| 153 |
|
| 154 | if (do_idr_lock)
|
| 155 | spin_unlock_bh(&map_idr_lock);
|
| 156 | else
|
| 157 | __release(&map_idr_lock);
|
| 158 | }
|
| 159 |
|
| 160 |
|
| 161 | static void bpf_map_free_deferred(struct work_struct *work)
|
| 162 | {
|
| 163 | struct bpf_map *map = container_of(work, struct bpf_map, work);
|
| 164 |
|
| 165 | bpf_map_uncharge_memlock(map);
|
| 166 |
|
| 167 | map->ops->map_free(map);
|
| 168 | }
|
| 169 |
|
| 170 | static void bpf_map_put_uref(struct bpf_map *map)
|
| 171 | {
|
| 172 | if (atomic_dec_and_test(&map->usercnt)) {
|
| 173 | if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY)
|
| 174 | bpf_fd_array_map_clear(map);
|
| 175 | }
|
| 176 | }
|
| 177 |
|
| 178 | |
| 179 | * (unrelying map implementation ops->map_free() might sleep)
|
| 180 |
|
| 181 | static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
|
| 182 | {
|
| 183 | if (atomic_dec_and_test(&map->refcnt)) {
|
| 184 |
|
| 185 | bpf_map_free_id(map, do_idr_lock);
|
| 186 | INIT_WORK(&map->work, bpf_map_free_deferred);
|
| 187 | schedule_work(&map->work);
|
| 188 | }
|
| 189 | }
|
| 190 |
|
| 191 | void bpf_map_put(struct bpf_map *map)
|
| 192 | {
|
| 193 | __bpf_map_put(map, true);
|
| 194 | }
|
| 195 |
|
| 196 | void bpf_map_put_with_uref(struct bpf_map *map)
|
| 197 | {
|
| 198 | bpf_map_put_uref(map);
|
| 199 | bpf_map_put(map);
|
| 200 | }
|
| 201 |
|
| 202 | static int bpf_map_release(struct inode *inode, struct file *filp)
|
| 203 | {
|
| 204 | struct bpf_map *map = filp->private_data;
|
| 205 |
|
| 206 | if (map->ops->map_release)
|
| 207 | map->ops->map_release(map, filp);
|
| 208 |
|
| 209 | bpf_map_put_with_uref(map);
|
| 210 | return 0;
|
| 211 | }
|
| 212 |
|
| 213 | #ifdef CONFIG_PROC_FS
|
| 214 | static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
|
| 215 | {
|
| 216 | const struct bpf_map *map = filp->private_data;
|
| 217 | const struct bpf_array *array;
|
| 218 | u32 owner_prog_type = 0;
|
| 219 | u32 owner_jited = 0;
|
| 220 |
|
| 221 | if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
|
| 222 | array = container_of(map, struct bpf_array, map);
|
| 223 | owner_prog_type = array->owner_prog_type;
|
| 224 | owner_jited = array->owner_jited;
|
| 225 | }
|
| 226 |
|
| 227 | seq_printf(m,
|
| 228 | "map_type:\t%u\n"
|
| 229 | "key_size:\t%u\n"
|
| 230 | "value_size:\t%u\n"
|
| 231 | "max_entries:\t%u\n"
|
| 232 | "map_flags:\t%#x\n"
|
| 233 | "memlock:\t%llu\n",
|
| 234 | map->map_type,
|
| 235 | map->key_size,
|
| 236 | map->value_size,
|
| 237 | map->max_entries,
|
| 238 | map->map_flags,
|
| 239 | map->pages * 1ULL << PAGE_SHIFT);
|
| 240 |
|
| 241 | if (owner_prog_type) {
|
| 242 | seq_printf(m, "owner_prog_type:\t%u\n",
|
| 243 | owner_prog_type);
|
| 244 | seq_printf(m, "owner_jited:\t%u\n",
|
| 245 | owner_jited);
|
| 246 | }
|
| 247 | }
|
| 248 | #endif
|
| 249 |
|
| 250 | static const struct file_operations bpf_map_fops = {
|
| 251 | #ifdef CONFIG_PROC_FS
|
| 252 | .show_fdinfo = bpf_map_show_fdinfo,
|
| 253 | #endif
|
| 254 | .release = bpf_map_release,
|
| 255 | };
|
| 256 |
|
| 257 | int bpf_map_new_fd(struct bpf_map *map)
|
| 258 | {
|
| 259 | return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
|
| 260 | O_RDWR | O_CLOEXEC);
|
| 261 | }
|
| 262 |
|
| 263 |
|
| 264 | #define CHECK_ATTR(CMD) \
|
| 265 | memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
|
| 266 | sizeof(attr->CMD##_LAST_FIELD), 0, \
|
| 267 | sizeof(*attr) - \
|
| 268 | offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
|
| 269 | sizeof(attr->CMD##_LAST_FIELD)) != NULL
|
| 270 |
|
| 271 | #define BPF_MAP_CREATE_LAST_FIELD inner_map_fd
|
| 272 |
|
| 273 | static int map_create(union bpf_attr *attr)
|
| 274 | {
|
| 275 | struct bpf_map *map;
|
| 276 | int err;
|
| 277 |
|
| 278 | err = CHECK_ATTR(BPF_MAP_CREATE);
|
| 279 | if (err)
|
| 280 | return -EINVAL;
|
| 281 |
|
| 282 |
|
| 283 | map = find_and_alloc_map(attr);
|
| 284 | if (IS_ERR(map))
|
| 285 | return PTR_ERR(map);
|
| 286 |
|
| 287 | atomic_set(&map->refcnt, 1);
|
| 288 | atomic_set(&map->usercnt, 1);
|
| 289 |
|
| 290 | err = bpf_map_charge_memlock(map);
|
| 291 | if (err)
|
| 292 | goto free_map_nouncharge;
|
| 293 |
|
| 294 | err = bpf_map_alloc_id(map);
|
| 295 | if (err)
|
| 296 | goto free_map;
|
| 297 |
|
| 298 | err = bpf_map_new_fd(map);
|
| 299 | if (err < 0) {
|
| 300 | |
| 301 | * bpf_map_put() is needed because the above
|
| 302 | * bpf_map_alloc_id() has published the map
|
| 303 | * to the userspace and the userspace may
|
| 304 | * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
|
| 305 |
|
| 306 | bpf_map_put(map);
|
| 307 | return err;
|
| 308 | }
|
| 309 |
|
| 310 | trace_bpf_map_create(map, err);
|
| 311 | return err;
|
| 312 |
|
| 313 | free_map:
|
| 314 | bpf_map_uncharge_memlock(map);
|
| 315 | free_map_nouncharge:
|
| 316 | map->ops->map_free(map);
|
| 317 | return err;
|
| 318 | }
|
| 319 |
|
| 320 | |
| 321 | * On success caller should complete fd access with matching fdput()
|
| 322 |
|
| 323 | struct bpf_map *__bpf_map_get(struct fd f)
|
| 324 | {
|
| 325 | if (!f.file)
|
| 326 | return ERR_PTR(-EBADF);
|
| 327 | if (f.file->f_op != &bpf_map_fops) {
|
| 328 | fdput(f);
|
| 329 | return ERR_PTR(-EINVAL);
|
| 330 | }
|
| 331 |
|
| 332 | return f.file->private_data;
|
| 333 | }
|
| 334 |
|
| 335 |
|
| 336 | #define BPF_MAX_REFCNT 32768
|
| 337 |
|
| 338 | struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
|
| 339 | {
|
| 340 | if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
|
| 341 | atomic_dec(&map->refcnt);
|
| 342 | return ERR_PTR(-EBUSY);
|
| 343 | }
|
| 344 | if (uref)
|
| 345 | atomic_inc(&map->usercnt);
|
| 346 | return map;
|
| 347 | }
|
| 348 |
|
| 349 | struct bpf_map *bpf_map_get_with_uref(u32 ufd)
|
| 350 | {
|
| 351 | struct fd f = fdget(ufd);
|
| 352 | struct bpf_map *map;
|
| 353 |
|
| 354 | map = __bpf_map_get(f);
|
| 355 | if (IS_ERR(map))
|
| 356 | return map;
|
| 357 |
|
| 358 | map = bpf_map_inc(map, true);
|
| 359 | fdput(f);
|
| 360 |
|
| 361 | return map;
|
| 362 | }
|
| 363 |
|
| 364 |
|
| 365 | static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
|
| 366 | bool uref)
|
| 367 | {
|
| 368 | int refold;
|
| 369 |
|
| 370 | refold = __atomic_add_unless(&map->refcnt, 1, 0);
|
| 371 |
|
| 372 | if (refold >= BPF_MAX_REFCNT) {
|
| 373 | __bpf_map_put(map, false);
|
| 374 | return ERR_PTR(-EBUSY);
|
| 375 | }
|
| 376 |
|
| 377 | if (!refold)
|
| 378 | return ERR_PTR(-ENOENT);
|
| 379 |
|
| 380 | if (uref)
|
| 381 | atomic_inc(&map->usercnt);
|
| 382 |
|
| 383 | return map;
|
| 384 | }
|
| 385 |
|
| 386 | int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
|
| 387 | {
|
| 388 | return -ENOTSUPP;
|
| 389 | }
|
| 390 |
|
| 391 |
|
| 392 | #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
|
| 393 |
|
| 394 | static int map_lookup_elem(union bpf_attr *attr)
|
| 395 | {
|
| 396 | void __user *ukey = u64_to_user_ptr(attr->key);
|
| 397 | void __user *uvalue = u64_to_user_ptr(attr->value);
|
| 398 | int ufd = attr->map_fd;
|
| 399 | struct bpf_map *map;
|
| 400 | void *key, *value, *ptr;
|
| 401 | u32 value_size;
|
| 402 | struct fd f;
|
| 403 | int err;
|
| 404 |
|
| 405 | if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
|
| 406 | return -EINVAL;
|
| 407 |
|
| 408 | f = fdget(ufd);
|
| 409 | map = __bpf_map_get(f);
|
| 410 | if (IS_ERR(map))
|
| 411 | return PTR_ERR(map);
|
| 412 |
|
| 413 | key = memdup_user(ukey, map->key_size);
|
| 414 | if (IS_ERR(key)) {
|
| 415 | err = PTR_ERR(key);
|
| 416 | goto err_put;
|
| 417 | }
|
| 418 |
|
| 419 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
| 420 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
|
| 421 | map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
|
| 422 | value_size = round_up(map->value_size, 8) * num_possible_cpus();
|
| 423 | else if (IS_FD_MAP(map))
|
| 424 | value_size = sizeof(u32);
|
| 425 | else
|
| 426 | value_size = map->value_size;
|
| 427 |
|
| 428 | err = -ENOMEM;
|
| 429 | value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
|
| 430 | if (!value)
|
| 431 | goto free_key;
|
| 432 |
|
| 433 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
| 434 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
|
| 435 | err = bpf_percpu_hash_copy(map, key, value);
|
| 436 | } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
| 437 | err = bpf_percpu_array_copy(map, key, value);
|
| 438 | } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
|
| 439 | err = bpf_stackmap_copy(map, key, value);
|
| 440 | } else if (IS_FD_ARRAY(map)) {
|
| 441 | err = bpf_fd_array_map_lookup_elem(map, key, value);
|
| 442 | } else if (IS_FD_HASH(map)) {
|
| 443 | err = bpf_fd_htab_map_lookup_elem(map, key, value);
|
| 444 | } else {
|
| 445 | rcu_read_lock();
|
| 446 | ptr = map->ops->map_lookup_elem(map, key);
|
| 447 | if (ptr)
|
| 448 | memcpy(value, ptr, value_size);
|
| 449 | rcu_read_unlock();
|
| 450 | err = ptr ? 0 : -ENOENT;
|
| 451 | }
|
| 452 |
|
| 453 | if (err)
|
| 454 | goto free_value;
|
| 455 |
|
| 456 | err = -EFAULT;
|
| 457 | if (copy_to_user(uvalue, value, value_size) != 0)
|
| 458 | goto free_value;
|
| 459 |
|
| 460 | trace_bpf_map_lookup_elem(map, ufd, key, value);
|
| 461 | err = 0;
|
| 462 |
|
| 463 | free_value:
|
| 464 | kfree(value);
|
| 465 | free_key:
|
| 466 | kfree(key);
|
| 467 | err_put:
|
| 468 | fdput(f);
|
| 469 | return err;
|
| 470 | }
|
| 471 |
|
| 472 | #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
|
| 473 |
|
| 474 | static int map_update_elem(union bpf_attr *attr)
|
| 475 | {
|
| 476 | void __user *ukey = u64_to_user_ptr(attr->key);
|
| 477 | void __user *uvalue = u64_to_user_ptr(attr->value);
|
| 478 | int ufd = attr->map_fd;
|
| 479 | struct bpf_map *map;
|
| 480 | void *key, *value;
|
| 481 | u32 value_size;
|
| 482 | struct fd f;
|
| 483 | int err;
|
| 484 |
|
| 485 | if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
|
| 486 | return -EINVAL;
|
| 487 |
|
| 488 | f = fdget(ufd);
|
| 489 | map = __bpf_map_get(f);
|
| 490 | if (IS_ERR(map))
|
| 491 | return PTR_ERR(map);
|
| 492 |
|
| 493 | key = memdup_user(ukey, map->key_size);
|
| 494 | if (IS_ERR(key)) {
|
| 495 | err = PTR_ERR(key);
|
| 496 | goto err_put;
|
| 497 | }
|
| 498 |
|
| 499 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
| 500 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
|
| 501 | map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
|
| 502 | value_size = round_up(map->value_size, 8) * num_possible_cpus();
|
| 503 | else
|
| 504 | value_size = map->value_size;
|
| 505 |
|
| 506 | err = -ENOMEM;
|
| 507 | value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
|
| 508 | if (!value)
|
| 509 | goto free_key;
|
| 510 |
|
| 511 | err = -EFAULT;
|
| 512 | if (copy_from_user(value, uvalue, value_size) != 0)
|
| 513 | goto free_value;
|
| 514 |
|
| 515 | |
| 516 | * inside bpf map update or delete otherwise deadlocks are possible
|
| 517 |
|
| 518 | preempt_disable();
|
| 519 | __this_cpu_inc(bpf_prog_active);
|
| 520 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
| 521 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
|
| 522 | err = bpf_percpu_hash_update(map, key, value, attr->flags);
|
| 523 | } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
| 524 | err = bpf_percpu_array_update(map, key, value, attr->flags);
|
| 525 | } else if (map->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY ||
|
| 526 | map->map_type == BPF_MAP_TYPE_PROG_ARRAY ||
|
| 527 | map->map_type == BPF_MAP_TYPE_CGROUP_ARRAY ||
|
| 528 | map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) {
|
| 529 | rcu_read_lock();
|
| 530 | err = bpf_fd_array_map_update_elem(map, f.file, key, value,
|
| 531 | attr->flags);
|
| 532 | rcu_read_unlock();
|
| 533 | } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
|
| 534 | rcu_read_lock();
|
| 535 | err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
|
| 536 | attr->flags);
|
| 537 | rcu_read_unlock();
|
| 538 | } else {
|
| 539 | rcu_read_lock();
|
| 540 | err = map->ops->map_update_elem(map, key, value, attr->flags);
|
| 541 | rcu_read_unlock();
|
| 542 | }
|
| 543 | __this_cpu_dec(bpf_prog_active);
|
| 544 | preempt_enable();
|
| 545 |
|
| 546 | if (!err)
|
| 547 | trace_bpf_map_update_elem(map, ufd, key, value);
|
| 548 | free_value:
|
| 549 | kfree(value);
|
| 550 | free_key:
|
| 551 | kfree(key);
|
| 552 | err_put:
|
| 553 | fdput(f);
|
| 554 | return err;
|
| 555 | }
|
| 556 |
|
| 557 | #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
|
| 558 |
|
| 559 | static int map_delete_elem(union bpf_attr *attr)
|
| 560 | {
|
| 561 | void __user *ukey = u64_to_user_ptr(attr->key);
|
| 562 | int ufd = attr->map_fd;
|
| 563 | struct bpf_map *map;
|
| 564 | struct fd f;
|
| 565 | void *key;
|
| 566 | int err;
|
| 567 |
|
| 568 | if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
|
| 569 | return -EINVAL;
|
| 570 |
|
| 571 | f = fdget(ufd);
|
| 572 | map = __bpf_map_get(f);
|
| 573 | if (IS_ERR(map))
|
| 574 | return PTR_ERR(map);
|
| 575 |
|
| 576 | key = memdup_user(ukey, map->key_size);
|
| 577 | if (IS_ERR(key)) {
|
| 578 | err = PTR_ERR(key);
|
| 579 | goto err_put;
|
| 580 | }
|
| 581 |
|
| 582 | preempt_disable();
|
| 583 | __this_cpu_inc(bpf_prog_active);
|
| 584 | rcu_read_lock();
|
| 585 | err = map->ops->map_delete_elem(map, key);
|
| 586 | rcu_read_unlock();
|
| 587 | __this_cpu_dec(bpf_prog_active);
|
| 588 | preempt_enable();
|
| 589 |
|
| 590 | if (!err)
|
| 591 | trace_bpf_map_delete_elem(map, ufd, key);
|
| 592 | kfree(key);
|
| 593 | err_put:
|
| 594 | fdput(f);
|
| 595 | return err;
|
| 596 | }
|
| 597 |
|
| 598 |
|
| 599 | #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
|
| 600 |
|
| 601 | static int map_get_next_key(union bpf_attr *attr)
|
| 602 | {
|
| 603 | void __user *ukey = u64_to_user_ptr(attr->key);
|
| 604 | void __user *unext_key = u64_to_user_ptr(attr->next_key);
|
| 605 | int ufd = attr->map_fd;
|
| 606 | struct bpf_map *map;
|
| 607 | void *key, *next_key;
|
| 608 | struct fd f;
|
| 609 | int err;
|
| 610 |
|
| 611 | if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
|
| 612 | return -EINVAL;
|
| 613 |
|
| 614 | f = fdget(ufd);
|
| 615 | map = __bpf_map_get(f);
|
| 616 | if (IS_ERR(map))
|
| 617 | return PTR_ERR(map);
|
| 618 |
|
| 619 | if (ukey) {
|
| 620 | key = memdup_user(ukey, map->key_size);
|
| 621 | if (IS_ERR(key)) {
|
| 622 | err = PTR_ERR(key);
|
| 623 | goto err_put;
|
| 624 | }
|
| 625 | } else {
|
| 626 | key = NULL;
|
| 627 | }
|
| 628 |
|
| 629 | err = -ENOMEM;
|
| 630 | next_key = kmalloc(map->key_size, GFP_USER);
|
| 631 | if (!next_key)
|
| 632 | goto free_key;
|
| 633 |
|
| 634 | rcu_read_lock();
|
| 635 | err = map->ops->map_get_next_key(map, key, next_key);
|
| 636 | rcu_read_unlock();
|
| 637 | if (err)
|
| 638 | goto free_next_key;
|
| 639 |
|
| 640 | err = -EFAULT;
|
| 641 | if (copy_to_user(unext_key, next_key, map->key_size) != 0)
|
| 642 | goto free_next_key;
|
| 643 |
|
| 644 | trace_bpf_map_next_key(map, ufd, key, next_key);
|
| 645 | err = 0;
|
| 646 |
|
| 647 | free_next_key:
|
| 648 | kfree(next_key);
|
| 649 | free_key:
|
| 650 | kfree(key);
|
| 651 | err_put:
|
| 652 | fdput(f);
|
| 653 | return err;
|
| 654 | }
|
| 655 |
|
| 656 | static const struct bpf_verifier_ops * const bpf_prog_types[] = {
|
| 657 | #define BPF_PROG_TYPE(_id, _ops) \
|
| 658 | [_id] = &_ops,
|
| 659 | #define BPF_MAP_TYPE(_id, _ops)
|
| 660 | #include <linux/bpf_types.h>
|
| 661 | #undef BPF_PROG_TYPE
|
| 662 | #undef BPF_MAP_TYPE
|
| 663 | };
|
| 664 |
|
| 665 | static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
|
| 666 | {
|
| 667 | if (type >= ARRAY_SIZE(bpf_prog_types) || !bpf_prog_types[type])
|
| 668 | return -EINVAL;
|
| 669 |
|
| 670 | prog->aux->ops = bpf_prog_types[type];
|
| 671 | prog->type = type;
|
| 672 | return 0;
|
| 673 | }
|
| 674 |
|
| 675 |
|
| 676 | static void free_used_maps(struct bpf_prog_aux *aux)
|
| 677 | {
|
| 678 | int i;
|
| 679 |
|
| 680 | for (i = 0; i < aux->used_map_cnt; i++)
|
| 681 | bpf_map_put(aux->used_maps[i]);
|
| 682 |
|
| 683 | kfree(aux->used_maps);
|
| 684 | }
|
| 685 |
|
| 686 | int __bpf_prog_charge(struct user_struct *user, u32 pages)
|
| 687 | {
|
| 688 | unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
|
| 689 | unsigned long user_bufs;
|
| 690 |
|
| 691 | if (user) {
|
| 692 | user_bufs = atomic_long_add_return(pages, &user->locked_vm);
|
| 693 | if (user_bufs > memlock_limit) {
|
| 694 | atomic_long_sub(pages, &user->locked_vm);
|
| 695 | return -EPERM;
|
| 696 | }
|
| 697 | }
|
| 698 |
|
| 699 | return 0;
|
| 700 | }
|
| 701 |
|
| 702 | void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
|
| 703 | {
|
| 704 | if (user)
|
| 705 | atomic_long_sub(pages, &user->locked_vm);
|
| 706 | }
|
| 707 |
|
| 708 | static int bpf_prog_charge_memlock(struct bpf_prog *prog)
|
| 709 | {
|
| 710 | struct user_struct *user = get_current_user();
|
| 711 | int ret;
|
| 712 |
|
| 713 | ret = __bpf_prog_charge(user, prog->pages);
|
| 714 | if (ret) {
|
| 715 | free_uid(user);
|
| 716 | return ret;
|
| 717 | }
|
| 718 |
|
| 719 | prog->aux->user = user;
|
| 720 | return 0;
|
| 721 | }
|
| 722 |
|
| 723 | static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
|
| 724 | {
|
| 725 | struct user_struct *user = prog->aux->user;
|
| 726 |
|
| 727 | __bpf_prog_uncharge(user, prog->pages);
|
| 728 | free_uid(user);
|
| 729 | }
|
| 730 |
|
| 731 | static int bpf_prog_alloc_id(struct bpf_prog *prog)
|
| 732 | {
|
| 733 | int id;
|
| 734 |
|
| 735 | spin_lock_bh(&prog_idr_lock);
|
| 736 | id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
|
| 737 | if (id > 0)
|
| 738 | prog->aux->id = id;
|
| 739 | spin_unlock_bh(&prog_idr_lock);
|
| 740 |
|
| 741 |
|
| 742 | if (WARN_ON_ONCE(!id))
|
| 743 | return -ENOSPC;
|
| 744 |
|
| 745 | return id > 0 ? 0 : id;
|
| 746 | }
|
| 747 |
|
| 748 | static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
|
| 749 | {
|
| 750 |
|
| 751 | if (!prog->aux->id)
|
| 752 | return;
|
| 753 |
|
| 754 | if (do_idr_lock)
|
| 755 | spin_lock_bh(&prog_idr_lock);
|
| 756 | else
|
| 757 | __acquire(&prog_idr_lock);
|
| 758 |
|
| 759 | idr_remove(&prog_idr, prog->aux->id);
|
| 760 |
|
| 761 | if (do_idr_lock)
|
| 762 | spin_unlock_bh(&prog_idr_lock);
|
| 763 | else
|
| 764 | __release(&prog_idr_lock);
|
| 765 | }
|
| 766 |
|
| 767 | static void __bpf_prog_put_rcu(struct rcu_head *rcu)
|
| 768 | {
|
| 769 | struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
|
| 770 |
|
| 771 | free_used_maps(aux);
|
| 772 | bpf_prog_uncharge_memlock(aux->prog);
|
| 773 | bpf_prog_free(aux->prog);
|
| 774 | }
|
| 775 |
|
| 776 | static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
|
| 777 | {
|
| 778 | if (atomic_dec_and_test(&prog->aux->refcnt)) {
|
| 779 | trace_bpf_prog_put_rcu(prog);
|
| 780 |
|
| 781 | bpf_prog_free_id(prog, do_idr_lock);
|
| 782 | bpf_prog_kallsyms_del(prog);
|
| 783 | call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
|
| 784 | }
|
| 785 | }
|
| 786 |
|
| 787 | void bpf_prog_put(struct bpf_prog *prog)
|
| 788 | {
|
| 789 | __bpf_prog_put(prog, true);
|
| 790 | }
|
| 791 | EXPORT_SYMBOL_GPL(bpf_prog_put);
|
| 792 |
|
| 793 | static int bpf_prog_release(struct inode *inode, struct file *filp)
|
| 794 | {
|
| 795 | struct bpf_prog *prog = filp->private_data;
|
| 796 |
|
| 797 | bpf_prog_put(prog);
|
| 798 | return 0;
|
| 799 | }
|
| 800 |
|
| 801 | #ifdef CONFIG_PROC_FS
|
| 802 | static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
|
| 803 | {
|
| 804 | const struct bpf_prog *prog = filp->private_data;
|
| 805 | char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
|
| 806 |
|
| 807 | bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
|
| 808 | seq_printf(m,
|
| 809 | "prog_type:\t%u\n"
|
| 810 | "prog_jited:\t%u\n"
|
| 811 | "prog_tag:\t%s\n"
|
| 812 | "memlock:\t%llu\n",
|
| 813 | prog->type,
|
| 814 | prog->jited,
|
| 815 | prog_tag,
|
| 816 | prog->pages * 1ULL << PAGE_SHIFT);
|
| 817 | }
|
| 818 | #endif
|
| 819 |
|
| 820 | static const struct file_operations bpf_prog_fops = {
|
| 821 | #ifdef CONFIG_PROC_FS
|
| 822 | .show_fdinfo = bpf_prog_show_fdinfo,
|
| 823 | #endif
|
| 824 | .release = bpf_prog_release,
|
| 825 | };
|
| 826 |
|
| 827 | int bpf_prog_new_fd(struct bpf_prog *prog)
|
| 828 | {
|
| 829 | return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
|
| 830 | O_RDWR | O_CLOEXEC);
|
| 831 | }
|
| 832 |
|
| 833 | static struct bpf_prog *____bpf_prog_get(struct fd f)
|
| 834 | {
|
| 835 | if (!f.file)
|
| 836 | return ERR_PTR(-EBADF);
|
| 837 | if (f.file->f_op != &bpf_prog_fops) {
|
| 838 | fdput(f);
|
| 839 | return ERR_PTR(-EINVAL);
|
| 840 | }
|
| 841 |
|
| 842 | return f.file->private_data;
|
| 843 | }
|
| 844 |
|
| 845 | struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
|
| 846 | {
|
| 847 | if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
|
| 848 | atomic_sub(i, &prog->aux->refcnt);
|
| 849 | return ERR_PTR(-EBUSY);
|
| 850 | }
|
| 851 | return prog;
|
| 852 | }
|
| 853 | EXPORT_SYMBOL_GPL(bpf_prog_add);
|
| 854 |
|
| 855 | void bpf_prog_sub(struct bpf_prog *prog, int i)
|
| 856 | {
|
| 857 | |
| 858 | * error path. We still know that another entity in our call
|
| 859 | * path holds a reference to the program, thus atomic_sub() can
|
| 860 | * be safely used in such cases!
|
| 861 |
|
| 862 | WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
|
| 863 | }
|
| 864 | EXPORT_SYMBOL_GPL(bpf_prog_sub);
|
| 865 |
|
| 866 | struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
|
| 867 | {
|
| 868 | return bpf_prog_add(prog, 1);
|
| 869 | }
|
| 870 | EXPORT_SYMBOL_GPL(bpf_prog_inc);
|
| 871 |
|
| 872 |
|
| 873 | static struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
|
| 874 | {
|
| 875 | int refold;
|
| 876 |
|
| 877 | refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0);
|
| 878 |
|
| 879 | if (refold >= BPF_MAX_REFCNT) {
|
| 880 | __bpf_prog_put(prog, false);
|
| 881 | return ERR_PTR(-EBUSY);
|
| 882 | }
|
| 883 |
|
| 884 | if (!refold)
|
| 885 | return ERR_PTR(-ENOENT);
|
| 886 |
|
| 887 | return prog;
|
| 888 | }
|
| 889 |
|
| 890 | static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *type)
|
| 891 | {
|
| 892 | struct fd f = fdget(ufd);
|
| 893 | struct bpf_prog *prog;
|
| 894 |
|
| 895 | prog = ____bpf_prog_get(f);
|
| 896 | if (IS_ERR(prog))
|
| 897 | return prog;
|
| 898 | if (type && prog->type != *type) {
|
| 899 | prog = ERR_PTR(-EINVAL);
|
| 900 | goto out;
|
| 901 | }
|
| 902 |
|
| 903 | prog = bpf_prog_inc(prog);
|
| 904 | out:
|
| 905 | fdput(f);
|
| 906 | return prog;
|
| 907 | }
|
| 908 |
|
| 909 | struct bpf_prog *bpf_prog_get(u32 ufd)
|
| 910 | {
|
| 911 | return __bpf_prog_get(ufd, NULL);
|
| 912 | }
|
| 913 |
|
| 914 | struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type)
|
| 915 | {
|
| 916 | struct bpf_prog *prog = __bpf_prog_get(ufd, &type);
|
| 917 |
|
| 918 | if (!IS_ERR(prog))
|
| 919 | trace_bpf_prog_get_type(prog);
|
| 920 | return prog;
|
| 921 | }
|
| 922 | EXPORT_SYMBOL_GPL(bpf_prog_get_type);
|
| 923 |
|
| 924 |
|
| 925 | #define BPF_PROG_LOAD_LAST_FIELD prog_flags
|
| 926 |
|
| 927 | static int bpf_prog_load(union bpf_attr *attr)
|
| 928 | {
|
| 929 | enum bpf_prog_type type = attr->prog_type;
|
| 930 | struct bpf_prog *prog;
|
| 931 | int err;
|
| 932 | char license[128];
|
| 933 | bool is_gpl;
|
| 934 |
|
| 935 | if (CHECK_ATTR(BPF_PROG_LOAD))
|
| 936 | return -EINVAL;
|
| 937 |
|
| 938 | if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT)
|
| 939 | return -EINVAL;
|
| 940 |
|
| 941 |
|
| 942 | if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
|
| 943 | sizeof(license) - 1) < 0)
|
| 944 | return -EFAULT;
|
| 945 | license[sizeof(license) - 1] = 0;
|
| 946 |
|
| 947 |
|
| 948 | is_gpl = license_is_gpl_compatible(license);
|
| 949 |
|
| 950 | if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS)
|
| 951 | return -E2BIG;
|
| 952 |
|
| 953 | if (type == BPF_PROG_TYPE_KPROBE &&
|
| 954 | attr->kern_version != LINUX_VERSION_CODE)
|
| 955 | return -EINVAL;
|
| 956 |
|
| 957 | if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
|
| 958 | type != BPF_PROG_TYPE_CGROUP_SKB &&
|
| 959 | !capable(CAP_SYS_ADMIN))
|
| 960 | return -EPERM;
|
| 961 |
|
| 962 |
|
| 963 | prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
|
| 964 | if (!prog)
|
| 965 | return -ENOMEM;
|
| 966 |
|
| 967 | err = bpf_prog_charge_memlock(prog);
|
| 968 | if (err)
|
| 969 | goto free_prog_nouncharge;
|
| 970 |
|
| 971 | prog->len = attr->insn_cnt;
|
| 972 |
|
| 973 | err = -EFAULT;
|
| 974 | if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
|
| 975 | bpf_prog_insn_size(prog)) != 0)
|
| 976 | goto free_prog;
|
| 977 |
|
| 978 | prog->orig_prog = NULL;
|
| 979 | prog->jited = 0;
|
| 980 |
|
| 981 | atomic_set(&prog->aux->refcnt, 1);
|
| 982 | prog->gpl_compatible = is_gpl ? 1 : 0;
|
| 983 |
|
| 984 |
|
| 985 | err = find_prog_type(type, prog);
|
| 986 | if (err < 0)
|
| 987 | goto free_prog;
|
| 988 |
|
| 989 |
|
| 990 | err = bpf_check(&prog, attr);
|
| 991 | if (err < 0)
|
| 992 | goto free_used_maps;
|
| 993 |
|
| 994 |
|
| 995 | prog = bpf_prog_select_runtime(prog, &err);
|
| 996 | if (err < 0)
|
| 997 | goto free_used_maps;
|
| 998 |
|
| 999 | err = bpf_prog_alloc_id(prog);
|
| 1000 | if (err)
|
| 1001 | goto free_used_maps;
|
| 1002 |
|
| 1003 | err = bpf_prog_new_fd(prog);
|
| 1004 | if (err < 0) {
|
| 1005 | |
| 1006 | * bpf_prog_put() is needed because the above
|
| 1007 | * bpf_prog_alloc_id() has published the prog
|
| 1008 | * to the userspace and the userspace may
|
| 1009 | * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
|
| 1010 |
|
| 1011 | bpf_prog_put(prog);
|
| 1012 | return err;
|
| 1013 | }
|
| 1014 |
|
| 1015 | bpf_prog_kallsyms_add(prog);
|
| 1016 | trace_bpf_prog_load(prog, err);
|
| 1017 | return err;
|
| 1018 |
|
| 1019 | free_used_maps:
|
| 1020 | free_used_maps(prog->aux);
|
| 1021 | free_prog:
|
| 1022 | bpf_prog_uncharge_memlock(prog);
|
| 1023 | free_prog_nouncharge:
|
| 1024 | bpf_prog_free(prog);
|
| 1025 | return err;
|
| 1026 | }
|
| 1027 |
|
| 1028 | #define BPF_OBJ_LAST_FIELD bpf_fd
|
| 1029 |
|
| 1030 | static int bpf_obj_pin(const union bpf_attr *attr)
|
| 1031 | {
|
| 1032 | if (CHECK_ATTR(BPF_OBJ))
|
| 1033 | return -EINVAL;
|
| 1034 |
|
| 1035 | return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
|
| 1036 | }
|
| 1037 |
|
| 1038 | static int bpf_obj_get(const union bpf_attr *attr)
|
| 1039 | {
|
| 1040 | if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0)
|
| 1041 | return -EINVAL;
|
| 1042 |
|
| 1043 | return bpf_obj_get_user(u64_to_user_ptr(attr->pathname));
|
| 1044 | }
|
| 1045 |
|
| 1046 | #ifdef CONFIG_CGROUP_BPF
|
| 1047 |
|
| 1048 | #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
|
| 1049 |
|
| 1050 | static int bpf_prog_attach(const union bpf_attr *attr)
|
| 1051 | {
|
| 1052 | enum bpf_prog_type ptype;
|
| 1053 | struct bpf_prog *prog;
|
| 1054 | struct cgroup *cgrp;
|
| 1055 | int ret;
|
| 1056 |
|
| 1057 | if (!capable(CAP_NET_ADMIN))
|
| 1058 | return -EPERM;
|
| 1059 |
|
| 1060 | if (CHECK_ATTR(BPF_PROG_ATTACH))
|
| 1061 | return -EINVAL;
|
| 1062 |
|
| 1063 | if (attr->attach_flags & ~BPF_F_ALLOW_OVERRIDE)
|
| 1064 | return -EINVAL;
|
| 1065 |
|
| 1066 | switch (attr->attach_type) {
|
| 1067 | case BPF_CGROUP_INET_INGRESS:
|
| 1068 | case BPF_CGROUP_INET_EGRESS:
|
| 1069 | ptype = BPF_PROG_TYPE_CGROUP_SKB;
|
| 1070 | break;
|
| 1071 | case BPF_CGROUP_INET_SOCK_CREATE:
|
| 1072 | ptype = BPF_PROG_TYPE_CGROUP_SOCK;
|
| 1073 | break;
|
| 1074 | case BPF_CGROUP_SOCK_OPS:
|
| 1075 | ptype = BPF_PROG_TYPE_SOCK_OPS;
|
| 1076 | break;
|
| 1077 | default:
|
| 1078 | return -EINVAL;
|
| 1079 | }
|
| 1080 |
|
| 1081 | prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
|
| 1082 | if (IS_ERR(prog))
|
| 1083 | return PTR_ERR(prog);
|
| 1084 |
|
| 1085 | cgrp = cgroup_get_from_fd(attr->target_fd);
|
| 1086 | if (IS_ERR(cgrp)) {
|
| 1087 | bpf_prog_put(prog);
|
| 1088 | return PTR_ERR(cgrp);
|
| 1089 | }
|
| 1090 |
|
| 1091 | ret = cgroup_bpf_update(cgrp, prog, attr->attach_type,
|
| 1092 | attr->attach_flags & BPF_F_ALLOW_OVERRIDE);
|
| 1093 | if (ret)
|
| 1094 | bpf_prog_put(prog);
|
| 1095 | cgroup_put(cgrp);
|
| 1096 |
|
| 1097 | return ret;
|
| 1098 | }
|
| 1099 |
|
| 1100 | #define BPF_PROG_DETACH_LAST_FIELD attach_type
|
| 1101 |
|
| 1102 | static int bpf_prog_detach(const union bpf_attr *attr)
|
| 1103 | {
|
| 1104 | struct cgroup *cgrp;
|
| 1105 | int ret;
|
| 1106 |
|
| 1107 | if (!capable(CAP_NET_ADMIN))
|
| 1108 | return -EPERM;
|
| 1109 |
|
| 1110 | if (CHECK_ATTR(BPF_PROG_DETACH))
|
| 1111 | return -EINVAL;
|
| 1112 |
|
| 1113 | switch (attr->attach_type) {
|
| 1114 | case BPF_CGROUP_INET_INGRESS:
|
| 1115 | case BPF_CGROUP_INET_EGRESS:
|
| 1116 | case BPF_CGROUP_INET_SOCK_CREATE:
|
| 1117 | case BPF_CGROUP_SOCK_OPS:
|
| 1118 | cgrp = cgroup_get_from_fd(attr->target_fd);
|
| 1119 | if (IS_ERR(cgrp))
|
| 1120 | return PTR_ERR(cgrp);
|
| 1121 |
|
| 1122 | ret = cgroup_bpf_update(cgrp, NULL, attr->attach_type, false);
|
| 1123 | cgroup_put(cgrp);
|
| 1124 | break;
|
| 1125 |
|
| 1126 | default:
|
| 1127 | return -EINVAL;
|
| 1128 | }
|
| 1129 |
|
| 1130 | return ret;
|
| 1131 | }
|
| 1132 |
|
| 1133 | #endif
|
| 1134 |
|
| 1135 | #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
|
| 1136 |
|
| 1137 | static int bpf_prog_test_run(const union bpf_attr *attr,
|
| 1138 | union bpf_attr __user *uattr)
|
| 1139 | {
|
| 1140 | struct bpf_prog *prog;
|
| 1141 | int ret = -ENOTSUPP;
|
| 1142 |
|
| 1143 | if (CHECK_ATTR(BPF_PROG_TEST_RUN))
|
| 1144 | return -EINVAL;
|
| 1145 |
|
| 1146 | prog = bpf_prog_get(attr->test.prog_fd);
|
| 1147 | if (IS_ERR(prog))
|
| 1148 | return PTR_ERR(prog);
|
| 1149 |
|
| 1150 | if (prog->aux->ops->test_run)
|
| 1151 | ret = prog->aux->ops->test_run(prog, attr, uattr);
|
| 1152 |
|
| 1153 | bpf_prog_put(prog);
|
| 1154 | return ret;
|
| 1155 | }
|
| 1156 |
|
| 1157 | #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
|
| 1158 |
|
| 1159 | static int bpf_obj_get_next_id(const union bpf_attr *attr,
|
| 1160 | union bpf_attr __user *uattr,
|
| 1161 | struct idr *idr,
|
| 1162 | spinlock_t *lock)
|
| 1163 | {
|
| 1164 | u32 next_id = attr->start_id;
|
| 1165 | int err = 0;
|
| 1166 |
|
| 1167 | if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
|
| 1168 | return -EINVAL;
|
| 1169 |
|
| 1170 | if (!capable(CAP_SYS_ADMIN))
|
| 1171 | return -EPERM;
|
| 1172 |
|
| 1173 | next_id++;
|
| 1174 | spin_lock_bh(lock);
|
| 1175 | if (!idr_get_next(idr, &next_id))
|
| 1176 | err = -ENOENT;
|
| 1177 | spin_unlock_bh(lock);
|
| 1178 |
|
| 1179 | if (!err)
|
| 1180 | err = put_user(next_id, &uattr->next_id);
|
| 1181 |
|
| 1182 | return err;
|
| 1183 | }
|
| 1184 |
|
| 1185 | #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
|
| 1186 |
|
| 1187 | static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
|
| 1188 | {
|
| 1189 | struct bpf_prog *prog;
|
| 1190 | u32 id = attr->prog_id;
|
| 1191 | int fd;
|
| 1192 |
|
| 1193 | if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
|
| 1194 | return -EINVAL;
|
| 1195 |
|
| 1196 | if (!capable(CAP_SYS_ADMIN))
|
| 1197 | return -EPERM;
|
| 1198 |
|
| 1199 | spin_lock_bh(&prog_idr_lock);
|
| 1200 | prog = idr_find(&prog_idr, id);
|
| 1201 | if (prog)
|
| 1202 | prog = bpf_prog_inc_not_zero(prog);
|
| 1203 | else
|
| 1204 | prog = ERR_PTR(-ENOENT);
|
| 1205 | spin_unlock_bh(&prog_idr_lock);
|
| 1206 |
|
| 1207 | if (IS_ERR(prog))
|
| 1208 | return PTR_ERR(prog);
|
| 1209 |
|
| 1210 | fd = bpf_prog_new_fd(prog);
|
| 1211 | if (fd < 0)
|
| 1212 | bpf_prog_put(prog);
|
| 1213 |
|
| 1214 | return fd;
|
| 1215 | }
|
| 1216 |
|
| 1217 | #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD map_id
|
| 1218 |
|
| 1219 | static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
|
| 1220 | {
|
| 1221 | struct bpf_map *map;
|
| 1222 | u32 id = attr->map_id;
|
| 1223 | int fd;
|
| 1224 |
|
| 1225 | if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID))
|
| 1226 | return -EINVAL;
|
| 1227 |
|
| 1228 | if (!capable(CAP_SYS_ADMIN))
|
| 1229 | return -EPERM;
|
| 1230 |
|
| 1231 | spin_lock_bh(&map_idr_lock);
|
| 1232 | map = idr_find(&map_idr, id);
|
| 1233 | if (map)
|
| 1234 | map = bpf_map_inc_not_zero(map, true);
|
| 1235 | else
|
| 1236 | map = ERR_PTR(-ENOENT);
|
| 1237 | spin_unlock_bh(&map_idr_lock);
|
| 1238 |
|
| 1239 | if (IS_ERR(map))
|
| 1240 | return PTR_ERR(map);
|
| 1241 |
|
| 1242 | fd = bpf_map_new_fd(map);
|
| 1243 | if (fd < 0)
|
| 1244 | bpf_map_put(map);
|
| 1245 |
|
| 1246 | return fd;
|
| 1247 | }
|
| 1248 |
|
| 1249 | static int check_uarg_tail_zero(void __user *uaddr,
|
| 1250 | size_t expected_size,
|
| 1251 | size_t actual_size)
|
| 1252 | {
|
| 1253 | unsigned char __user *addr;
|
| 1254 | unsigned char __user *end;
|
| 1255 | unsigned char val;
|
| 1256 | int err;
|
| 1257 |
|
| 1258 | if (actual_size <= expected_size)
|
| 1259 | return 0;
|
| 1260 |
|
| 1261 | addr = uaddr + expected_size;
|
| 1262 | end = uaddr + actual_size;
|
| 1263 |
|
| 1264 | for (; addr < end; addr++) {
|
| 1265 | err = get_user(val, addr);
|
| 1266 | if (err)
|
| 1267 | return err;
|
| 1268 | if (val)
|
| 1269 | return -E2BIG;
|
| 1270 | }
|
| 1271 |
|
| 1272 | return 0;
|
| 1273 | }
|
| 1274 |
|
| 1275 | static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
|
| 1276 | const union bpf_attr *attr,
|
| 1277 | union bpf_attr __user *uattr)
|
| 1278 | {
|
| 1279 | struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
|
| 1280 | struct bpf_prog_info info = {};
|
| 1281 | u32 info_len = attr->info.info_len;
|
| 1282 | char __user *uinsns;
|
| 1283 | u32 ulen;
|
| 1284 | int err;
|
| 1285 |
|
| 1286 | err = check_uarg_tail_zero(uinfo, sizeof(info), info_len);
|
| 1287 | if (err)
|
| 1288 | return err;
|
| 1289 | info_len = min_t(u32, sizeof(info), info_len);
|
| 1290 |
|
| 1291 | if (copy_from_user(&info, uinfo, info_len))
|
| 1292 | return -EFAULT;
|
| 1293 |
|
| 1294 | info.type = prog->type;
|
| 1295 | info.id = prog->aux->id;
|
| 1296 |
|
| 1297 | memcpy(info.tag, prog->tag, sizeof(prog->tag));
|
| 1298 |
|
| 1299 | if (!capable(CAP_SYS_ADMIN)) {
|
| 1300 | info.jited_prog_len = 0;
|
| 1301 | info.xlated_prog_len = 0;
|
| 1302 | goto done;
|
| 1303 | }
|
| 1304 |
|
| 1305 | ulen = info.jited_prog_len;
|
| 1306 | info.jited_prog_len = prog->jited_len;
|
| 1307 | if (info.jited_prog_len && ulen) {
|
| 1308 | uinsns = u64_to_user_ptr(info.jited_prog_insns);
|
| 1309 | ulen = min_t(u32, info.jited_prog_len, ulen);
|
| 1310 | if (copy_to_user(uinsns, prog->bpf_func, ulen))
|
| 1311 | return -EFAULT;
|
| 1312 | }
|
| 1313 |
|
| 1314 | ulen = info.xlated_prog_len;
|
| 1315 | info.xlated_prog_len = bpf_prog_insn_size(prog);
|
| 1316 | if (info.xlated_prog_len && ulen) {
|
| 1317 | uinsns = u64_to_user_ptr(info.xlated_prog_insns);
|
| 1318 | ulen = min_t(u32, info.xlated_prog_len, ulen);
|
| 1319 | if (copy_to_user(uinsns, prog->insnsi, ulen))
|
| 1320 | return -EFAULT;
|
| 1321 | }
|
| 1322 |
|
| 1323 | done:
|
| 1324 | if (copy_to_user(uinfo, &info, info_len) ||
|
| 1325 | put_user(info_len, &uattr->info.info_len))
|
| 1326 | return -EFAULT;
|
| 1327 |
|
| 1328 | return 0;
|
| 1329 | }
|
| 1330 |
|
| 1331 | static int bpf_map_get_info_by_fd(struct bpf_map *map,
|
| 1332 | const union bpf_attr *attr,
|
| 1333 | union bpf_attr __user *uattr)
|
| 1334 | {
|
| 1335 | struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
|
| 1336 | struct bpf_map_info info = {};
|
| 1337 | u32 info_len = attr->info.info_len;
|
| 1338 | int err;
|
| 1339 |
|
| 1340 | err = check_uarg_tail_zero(uinfo, sizeof(info), info_len);
|
| 1341 | if (err)
|
| 1342 | return err;
|
| 1343 | info_len = min_t(u32, sizeof(info), info_len);
|
| 1344 |
|
| 1345 | info.type = map->map_type;
|
| 1346 | info.id = map->id;
|
| 1347 | info.key_size = map->key_size;
|
| 1348 | info.value_size = map->value_size;
|
| 1349 | info.max_entries = map->max_entries;
|
| 1350 | info.map_flags = map->map_flags;
|
| 1351 |
|
| 1352 | if (copy_to_user(uinfo, &info, info_len) ||
|
| 1353 | put_user(info_len, &uattr->info.info_len))
|
| 1354 | return -EFAULT;
|
| 1355 |
|
| 1356 | return 0;
|
| 1357 | }
|
| 1358 |
|
| 1359 | #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
|
| 1360 |
|
| 1361 | static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
|
| 1362 | union bpf_attr __user *uattr)
|
| 1363 | {
|
| 1364 | int ufd = attr->info.bpf_fd;
|
| 1365 | struct fd f;
|
| 1366 | int err;
|
| 1367 |
|
| 1368 | if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
|
| 1369 | return -EINVAL;
|
| 1370 |
|
| 1371 | f = fdget(ufd);
|
| 1372 | if (!f.file)
|
| 1373 | return -EBADFD;
|
| 1374 |
|
| 1375 | if (f.file->f_op == &bpf_prog_fops)
|
| 1376 | err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
|
| 1377 | uattr);
|
| 1378 | else if (f.file->f_op == &bpf_map_fops)
|
| 1379 | err = bpf_map_get_info_by_fd(f.file->private_data, attr,
|
| 1380 | uattr);
|
| 1381 | else
|
| 1382 | err = -EINVAL;
|
| 1383 |
|
| 1384 | fdput(f);
|
| 1385 | return err;
|
| 1386 | }
|
| 1387 |
|
| 1388 | SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
|
| 1389 | {
|
| 1390 | union bpf_attr attr = {};
|
| 1391 | int err;
|
| 1392 |
|
| 1393 | if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled)
|
| 1394 | return -EPERM;
|
| 1395 |
|
| 1396 | if (!access_ok(VERIFY_READ, uattr, 1))
|
| 1397 | return -EFAULT;
|
| 1398 |
|
| 1399 | if (size > PAGE_SIZE)
|
| 1400 | return -E2BIG;
|
| 1401 |
|
| 1402 | |
| 1403 | * ensure all the unknown bits are 0 - i.e. new
|
| 1404 | * user-space does not rely on any kernel feature
|
| 1405 | * extensions we dont know about yet.
|
| 1406 |
|
| 1407 | err = check_uarg_tail_zero(uattr, sizeof(attr), size);
|
| 1408 | if (err)
|
| 1409 | return err;
|
| 1410 | size = min_t(u32, size, sizeof(attr));
|
| 1411 |
|
| 1412 |
|
| 1413 | if (copy_from_user(&attr, uattr, size) != 0)
|
| 1414 | return -EFAULT;
|
| 1415 |
|
| 1416 | switch (cmd) {
|
| 1417 | case BPF_MAP_CREATE:
|
| 1418 | err = map_create(&attr);
|
| 1419 | break;
|
| 1420 | case BPF_MAP_LOOKUP_ELEM:
|
| 1421 | err = map_lookup_elem(&attr);
|
| 1422 | break;
|
| 1423 | case BPF_MAP_UPDATE_ELEM:
|
| 1424 | err = map_update_elem(&attr);
|
| 1425 | break;
|
| 1426 | case BPF_MAP_DELETE_ELEM:
|
| 1427 | err = map_delete_elem(&attr);
|
| 1428 | break;
|
| 1429 | case BPF_MAP_GET_NEXT_KEY:
|
| 1430 | err = map_get_next_key(&attr);
|
| 1431 | break;
|
| 1432 | case BPF_PROG_LOAD:
|
| 1433 | err = bpf_prog_load(&attr);
|
| 1434 | break;
|
| 1435 | case BPF_OBJ_PIN:
|
| 1436 | err = bpf_obj_pin(&attr);
|
| 1437 | break;
|
| 1438 | case BPF_OBJ_GET:
|
| 1439 | err = bpf_obj_get(&attr);
|
| 1440 | break;
|
| 1441 | #ifdef CONFIG_CGROUP_BPF
|
| 1442 | case BPF_PROG_ATTACH:
|
| 1443 | err = bpf_prog_attach(&attr);
|
| 1444 | break;
|
| 1445 | case BPF_PROG_DETACH:
|
| 1446 | err = bpf_prog_detach(&attr);
|
| 1447 | break;
|
| 1448 | #endif
|
| 1449 | case BPF_PROG_TEST_RUN:
|
| 1450 | err = bpf_prog_test_run(&attr, uattr);
|
| 1451 | break;
|
| 1452 | case BPF_PROG_GET_NEXT_ID:
|
| 1453 | err = bpf_obj_get_next_id(&attr, uattr,
|
| 1454 | &prog_idr, &prog_idr_lock);
|
| 1455 | break;
|
| 1456 | case BPF_MAP_GET_NEXT_ID:
|
| 1457 | err = bpf_obj_get_next_id(&attr, uattr,
|
| 1458 | &map_idr, &map_idr_lock);
|
| 1459 | break;
|
| 1460 | case BPF_PROG_GET_FD_BY_ID:
|
| 1461 | err = bpf_prog_get_fd_by_id(&attr);
|
| 1462 | break;
|
| 1463 | case BPF_MAP_GET_FD_BY_ID:
|
| 1464 | err = bpf_map_get_fd_by_id(&attr);
|
| 1465 | break;
|
| 1466 | case BPF_OBJ_GET_INFO_BY_FD:
|
| 1467 | err = bpf_obj_get_info_by_fd(&attr, uattr);
|
| 1468 | break;
|
| 1469 | default:
|
| 1470 | err = -EINVAL;
|
| 1471 | break;
|
| 1472 | }
|
| 1473 |
|
| 1474 | return err;
|
| 1475 | }
|