1 /* 2 FUSE: Filesystem in Userspace 3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> 4 5 This program can be distributed under the terms of the GNU GPL. 6 See the file COPYING. 7 */ 8 9 #include "fuse_i.h" 10 11 #include <linux/pagemap.h> 12 #include <linux/slab.h> 13 #include <linux/file.h> 14 #include <linux/seq_file.h> 15 #include <linux/init.h> 16 #include <linux/module.h> 17 #include <linux/moduleparam.h> 18 #include <linux/fs_context.h> 19 #include <linux/fs_parser.h> 20 #include <linux/statfs.h> 21 #include <linux/random.h> 22 #include <linux/sched.h> 23 #include <linux/exportfs.h> 24 #include <linux/posix_acl.h> 25 #include <linux/pid_namespace.h> 26 #include <uapi/linux/magic.h> 27 28 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); 29 MODULE_DESCRIPTION("Filesystem in Userspace"); 30 MODULE_LICENSE("GPL"); 31 32 static struct kmem_cache *fuse_inode_cachep; 33 struct list_head fuse_conn_list; 34 DEFINE_MUTEX(fuse_mutex); 35 36 static int set_global_limit(const char *val, const struct kernel_param *kp); 37 38 unsigned max_user_bgreq; 39 module_param_call(max_user_bgreq, set_global_limit, param_get_uint, 40 &max_user_bgreq, 0644); 41 __MODULE_PARM_TYPE(max_user_bgreq, "uint"); 42 MODULE_PARM_DESC(max_user_bgreq, 43 "Global limit for the maximum number of backgrounded requests an " 44 "unprivileged user can set"); 45 46 unsigned max_user_congthresh; 47 module_param_call(max_user_congthresh, set_global_limit, param_get_uint, 48 &max_user_congthresh, 0644); 49 __MODULE_PARM_TYPE(max_user_congthresh, "uint"); 50 MODULE_PARM_DESC(max_user_congthresh, 51 "Global limit for the maximum congestion threshold an " 52 "unprivileged user can set"); 53 54 #define FUSE_DEFAULT_BLKSIZE 512 55 56 /** Maximum number of outstanding background requests */ 57 #define FUSE_DEFAULT_MAX_BACKGROUND 12 58 59 /** Congestion starts at 75% of maximum */ 60 #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4) 61 62 #ifdef CONFIG_BLOCK 63 static struct file_system_type fuseblk_fs_type; 64 #endif 65 66 struct fuse_forget_link *fuse_alloc_forget(void) 67 { 68 return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT); 69 } 70 71 static struct inode *fuse_alloc_inode(struct super_block *sb) 72 { 73 struct fuse_inode *fi; 74 75 fi = alloc_inode_sb(sb, fuse_inode_cachep, GFP_KERNEL); 76 if (!fi) 77 return NULL; 78 79 fi->i_time = 0; 80 fi->inval_mask = ~0; 81 fi->nodeid = 0; 82 fi->nlookup = 0; 83 fi->attr_version = 0; 84 fi->orig_ino = 0; 85 fi->state = 0; 86 mutex_init(&fi->mutex); 87 spin_lock_init(&fi->lock); 88 fi->forget = fuse_alloc_forget(); 89 if (!fi->forget) 90 goto out_free; 91 92 if (IS_ENABLED(CONFIG_FUSE_DAX) && !fuse_dax_inode_alloc(sb, fi)) 93 goto out_free_forget; 94 95 return &fi->inode; 96 97 out_free_forget: 98 kfree(fi->forget); 99 out_free: 100 kmem_cache_free(fuse_inode_cachep, fi); 101 return NULL; 102 } 103 104 static void fuse_free_inode(struct inode *inode) 105 { 106 struct fuse_inode *fi = get_fuse_inode(inode); 107 108 mutex_destroy(&fi->mutex); 109 kfree(fi->forget); 110 #ifdef CONFIG_FUSE_DAX 111 kfree(fi->dax); 112 #endif 113 kmem_cache_free(fuse_inode_cachep, fi); 114 } 115 116 static void fuse_evict_inode(struct inode *inode) 117 { 118 struct fuse_inode *fi = get_fuse_inode(inode); 119 120 /* Will write inode on close/munmap and in all other dirtiers */ 121 WARN_ON(inode->i_state & I_DIRTY_INODE); 122 123 truncate_inode_pages_final(&inode->i_data); 124 clear_inode(inode); 125 if (inode->i_sb->s_flags & SB_ACTIVE) { 126 struct fuse_conn *fc = get_fuse_conn(inode); 127 128 if (FUSE_IS_DAX(inode)) 129 fuse_dax_inode_cleanup(inode); 130 if (fi->nlookup) { 131 fuse_queue_forget(fc, fi->forget, fi->nodeid, 132 fi->nlookup); 133 fi->forget = NULL; 134 } 135 } 136 if (S_ISREG(inode->i_mode) && !fuse_is_bad(inode)) { 137 WARN_ON(!list_empty(&fi->write_files)); 138 WARN_ON(!list_empty(&fi->queued_writes)); 139 } 140 } 141 142 static int fuse_reconfigure(struct fs_context *fsc) 143 { 144 struct super_block *sb = fsc->root->d_sb; 145 146 sync_filesystem(sb); 147 if (fsc->sb_flags & SB_MANDLOCK) 148 return -EINVAL; 149 150 return 0; 151 } 152 153 /* 154 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down 155 * so that it will fit. 156 */ 157 static ino_t fuse_squash_ino(u64 ino64) 158 { 159 ino_t ino = (ino_t) ino64; 160 if (sizeof(ino_t) < sizeof(u64)) 161 ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8; 162 return ino; 163 } 164 165 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, 166 struct fuse_statx *sx, 167 u64 attr_valid, u32 cache_mask) 168 { 169 struct fuse_conn *fc = get_fuse_conn(inode); 170 struct fuse_inode *fi = get_fuse_inode(inode); 171 172 lockdep_assert_held(&fi->lock); 173 174 fi->attr_version = atomic64_inc_return(&fc->attr_version); 175 fi->i_time = attr_valid; 176 /* Clear basic stats from invalid mask */ 177 set_mask_bits(&fi->inval_mask, STATX_BASIC_STATS, 0); 178 179 inode->i_ino = fuse_squash_ino(attr->ino); 180 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); 181 set_nlink(inode, attr->nlink); 182 inode->i_uid = make_kuid(fc->user_ns, attr->uid); 183 inode->i_gid = make_kgid(fc->user_ns, attr->gid); 184 inode->i_blocks = attr->blocks; 185 186 /* Sanitize nsecs */ 187 attr->atimensec = min_t(u32, attr->atimensec, NSEC_PER_SEC - 1); 188 attr->mtimensec = min_t(u32, attr->mtimensec, NSEC_PER_SEC - 1); 189 attr->ctimensec = min_t(u32, attr->ctimensec, NSEC_PER_SEC - 1); 190 191 inode_set_atime(inode, attr->atime, attr->atimensec); 192 /* mtime from server may be stale due to local buffered write */ 193 if (!(cache_mask & STATX_MTIME)) { 194 inode_set_mtime(inode, attr->mtime, attr->mtimensec); 195 } 196 if (!(cache_mask & STATX_CTIME)) { 197 inode_set_ctime(inode, attr->ctime, attr->ctimensec); 198 } 199 if (sx) { 200 /* Sanitize nsecs */ 201 sx->btime.tv_nsec = 202 min_t(u32, sx->btime.tv_nsec, NSEC_PER_SEC - 1); 203 204 /* 205 * Btime has been queried, cache is valid (whether or not btime 206 * is available or not) so clear STATX_BTIME from inval_mask. 207 * 208 * Availability of the btime attribute is indicated in 209 * FUSE_I_BTIME 210 */ 211 set_mask_bits(&fi->inval_mask, STATX_BTIME, 0); 212 if (sx->mask & STATX_BTIME) { 213 set_bit(FUSE_I_BTIME, &fi->state); 214 fi->i_btime.tv_sec = sx->btime.tv_sec; 215 fi->i_btime.tv_nsec = sx->btime.tv_nsec; 216 } 217 } 218 219 if (attr->blksize != 0) 220 inode->i_blkbits = ilog2(attr->blksize); 221 else 222 inode->i_blkbits = inode->i_sb->s_blocksize_bits; 223 224 /* 225 * Don't set the sticky bit in i_mode, unless we want the VFS 226 * to check permissions. This prevents failures due to the 227 * check in may_delete(). 228 */ 229 fi->orig_i_mode = inode->i_mode; 230 if (!fc->default_permissions) 231 inode->i_mode &= ~S_ISVTX; 232 233 fi->orig_ino = attr->ino; 234 235 /* 236 * We are refreshing inode data and it is possible that another 237 * client set suid/sgid or security.capability xattr. So clear 238 * S_NOSEC. Ideally, we could have cleared it only if suid/sgid 239 * was set or if security.capability xattr was set. But we don't 240 * know if security.capability has been set or not. So clear it 241 * anyway. Its less efficient but should be safe. 242 */ 243 inode->i_flags &= ~S_NOSEC; 244 } 245 246 u32 fuse_get_cache_mask(struct inode *inode) 247 { 248 struct fuse_conn *fc = get_fuse_conn(inode); 249 250 if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) 251 return 0; 252 253 return STATX_MTIME | STATX_CTIME | STATX_SIZE; 254 } 255 256 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, 257 struct fuse_statx *sx, 258 u64 attr_valid, u64 attr_version) 259 { 260 struct fuse_conn *fc = get_fuse_conn(inode); 261 struct fuse_inode *fi = get_fuse_inode(inode); 262 u32 cache_mask; 263 loff_t oldsize; 264 struct timespec64 old_mtime; 265 266 spin_lock(&fi->lock); 267 /* 268 * In case of writeback_cache enabled, writes update mtime, ctime and 269 * may update i_size. In these cases trust the cached value in the 270 * inode. 271 */ 272 cache_mask = fuse_get_cache_mask(inode); 273 if (cache_mask & STATX_SIZE) 274 attr->size = i_size_read(inode); 275 276 if (cache_mask & STATX_MTIME) { 277 attr->mtime = inode_get_mtime_sec(inode); 278 attr->mtimensec = inode_get_mtime_nsec(inode); 279 } 280 if (cache_mask & STATX_CTIME) { 281 attr->ctime = inode_get_ctime_sec(inode); 282 attr->ctimensec = inode_get_ctime_nsec(inode); 283 } 284 285 if ((attr_version != 0 && fi->attr_version > attr_version) || 286 test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) { 287 spin_unlock(&fi->lock); 288 return; 289 } 290 291 old_mtime = inode_get_mtime(inode); 292 fuse_change_attributes_common(inode, attr, sx, attr_valid, cache_mask); 293 294 oldsize = inode->i_size; 295 /* 296 * In case of writeback_cache enabled, the cached writes beyond EOF 297 * extend local i_size without keeping userspace server in sync. So, 298 * attr->size coming from server can be stale. We cannot trust it. 299 */ 300 if (!(cache_mask & STATX_SIZE)) 301 i_size_write(inode, attr->size); 302 spin_unlock(&fi->lock); 303 304 if (!cache_mask && S_ISREG(inode->i_mode)) { 305 bool inval = false; 306 307 if (oldsize != attr->size) { 308 truncate_pagecache(inode, attr->size); 309 if (!fc->explicit_inval_data) 310 inval = true; 311 } else if (fc->auto_inval_data) { 312 struct timespec64 new_mtime = { 313 .tv_sec = attr->mtime, 314 .tv_nsec = attr->mtimensec, 315 }; 316 317 /* 318 * Auto inval mode also checks and invalidates if mtime 319 * has changed. 320 */ 321 if (!timespec64_equal(&old_mtime, &new_mtime)) 322 inval = true; 323 } 324 325 if (inval) 326 invalidate_inode_pages2(inode->i_mapping); 327 } 328 329 if (IS_ENABLED(CONFIG_FUSE_DAX)) 330 fuse_dax_dontcache(inode, attr->flags); 331 } 332 333 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr, 334 struct fuse_conn *fc) 335 { 336 inode->i_mode = attr->mode & S_IFMT; 337 inode->i_size = attr->size; 338 inode_set_mtime(inode, attr->mtime, attr->mtimensec); 339 inode_set_ctime(inode, attr->ctime, attr->ctimensec); 340 if (S_ISREG(inode->i_mode)) { 341 fuse_init_common(inode); 342 fuse_init_file_inode(inode, attr->flags); 343 } else if (S_ISDIR(inode->i_mode)) 344 fuse_init_dir(inode); 345 else if (S_ISLNK(inode->i_mode)) 346 fuse_init_symlink(inode); 347 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || 348 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { 349 fuse_init_common(inode); 350 init_special_inode(inode, inode->i_mode, 351 new_decode_dev(attr->rdev)); 352 } else 353 BUG(); 354 /* 355 * Ensure that we don't cache acls for daemons without FUSE_POSIX_ACL 356 * so they see the exact same behavior as before. 357 */ 358 if (!fc->posix_acl) 359 inode->i_acl = inode->i_default_acl = ACL_DONT_CACHE; 360 } 361 362 static int fuse_inode_eq(struct inode *inode, void *_nodeidp) 363 { 364 u64 nodeid = *(u64 *) _nodeidp; 365 if (get_node_id(inode) == nodeid) 366 return 1; 367 else 368 return 0; 369 } 370 371 static int fuse_inode_set(struct inode *inode, void *_nodeidp) 372 { 373 u64 nodeid = *(u64 *) _nodeidp; 374 get_fuse_inode(inode)->nodeid = nodeid; 375 return 0; 376 } 377 378 struct inode *fuse_iget(struct super_block *sb, u64 nodeid, 379 int generation, struct fuse_attr *attr, 380 u64 attr_valid, u64 attr_version) 381 { 382 struct inode *inode; 383 struct fuse_inode *fi; 384 struct fuse_conn *fc = get_fuse_conn_super(sb); 385 386 /* 387 * Auto mount points get their node id from the submount root, which is 388 * not a unique identifier within this filesystem. 389 * 390 * To avoid conflicts, do not place submount points into the inode hash 391 * table. 392 */ 393 if (fc->auto_submounts && (attr->flags & FUSE_ATTR_SUBMOUNT) && 394 S_ISDIR(attr->mode)) { 395 inode = new_inode(sb); 396 if (!inode) 397 return NULL; 398 399 fuse_init_inode(inode, attr, fc); 400 get_fuse_inode(inode)->nodeid = nodeid; 401 inode->i_flags |= S_AUTOMOUNT; 402 goto done; 403 } 404 405 retry: 406 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid); 407 if (!inode) 408 return NULL; 409 410 if ((inode->i_state & I_NEW)) { 411 inode->i_flags |= S_NOATIME; 412 if (!fc->writeback_cache || !S_ISREG(attr->mode)) 413 inode->i_flags |= S_NOCMTIME; 414 inode->i_generation = generation; 415 fuse_init_inode(inode, attr, fc); 416 unlock_new_inode(inode); 417 } else if (fuse_stale_inode(inode, generation, attr)) { 418 /* nodeid was reused, any I/O on the old inode should fail */ 419 fuse_make_bad(inode); 420 iput(inode); 421 goto retry; 422 } 423 done: 424 fi = get_fuse_inode(inode); 425 spin_lock(&fi->lock); 426 fi->nlookup++; 427 spin_unlock(&fi->lock); 428 fuse_change_attributes(inode, attr, NULL, attr_valid, attr_version); 429 430 return inode; 431 } 432 433 struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid, 434 struct fuse_mount **fm) 435 { 436 struct fuse_mount *fm_iter; 437 struct inode *inode; 438 439 WARN_ON(!rwsem_is_locked(&fc->killsb)); 440 list_for_each_entry(fm_iter, &fc->mounts, fc_entry) { 441 if (!fm_iter->sb) 442 continue; 443 444 inode = ilookup5(fm_iter->sb, nodeid, fuse_inode_eq, &nodeid); 445 if (inode) { 446 if (fm) 447 *fm = fm_iter; 448 return inode; 449 } 450 } 451 452 return NULL; 453 } 454 455 int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid, 456 loff_t offset, loff_t len) 457 { 458 struct fuse_inode *fi; 459 struct inode *inode; 460 pgoff_t pg_start; 461 pgoff_t pg_end; 462 463 inode = fuse_ilookup(fc, nodeid, NULL); 464 if (!inode) 465 return -ENOENT; 466 467 fi = get_fuse_inode(inode); 468 spin_lock(&fi->lock); 469 fi->attr_version = atomic64_inc_return(&fc->attr_version); 470 spin_unlock(&fi->lock); 471 472 fuse_invalidate_attr(inode); 473 forget_all_cached_acls(inode); 474 if (offset >= 0) { 475 pg_start = offset >> PAGE_SHIFT; 476 if (len <= 0) 477 pg_end = -1; 478 else 479 pg_end = (offset + len - 1) >> PAGE_SHIFT; 480 invalidate_inode_pages2_range(inode->i_mapping, 481 pg_start, pg_end); 482 } 483 iput(inode); 484 return 0; 485 } 486 487 bool fuse_lock_inode(struct inode *inode) 488 { 489 bool locked = false; 490 491 if (!get_fuse_conn(inode)->parallel_dirops) { 492 mutex_lock(&get_fuse_inode(inode)->mutex); 493 locked = true; 494 } 495 496 return locked; 497 } 498 499 void fuse_unlock_inode(struct inode *inode, bool locked) 500 { 501 if (locked) 502 mutex_unlock(&get_fuse_inode(inode)->mutex); 503 } 504 505 static void fuse_umount_begin(struct super_block *sb) 506 { 507 struct fuse_conn *fc = get_fuse_conn_super(sb); 508 509 if (fc->no_force_umount) 510 return; 511 512 fuse_abort_conn(fc); 513 514 // Only retire block-device-based superblocks. 515 if (sb->s_bdev != NULL) 516 retire_super(sb); 517 } 518 519 static void fuse_send_destroy(struct fuse_mount *fm) 520 { 521 if (fm->fc->conn_init) { 522 FUSE_ARGS(args); 523 524 args.opcode = FUSE_DESTROY; 525 args.force = true; 526 args.nocreds = true; 527 fuse_simple_request(fm, &args); 528 } 529 } 530 531 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) 532 { 533 stbuf->f_type = FUSE_SUPER_MAGIC; 534 stbuf->f_bsize = attr->bsize; 535 stbuf->f_frsize = attr->frsize; 536 stbuf->f_blocks = attr->blocks; 537 stbuf->f_bfree = attr->bfree; 538 stbuf->f_bavail = attr->bavail; 539 stbuf->f_files = attr->files; 540 stbuf->f_ffree = attr->ffree; 541 stbuf->f_namelen = attr->namelen; 542 /* fsid is left zero */ 543 } 544 545 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf) 546 { 547 struct super_block *sb = dentry->d_sb; 548 struct fuse_mount *fm = get_fuse_mount_super(sb); 549 FUSE_ARGS(args); 550 struct fuse_statfs_out outarg; 551 int err; 552 553 if (!fuse_allow_current_process(fm->fc)) { 554 buf->f_type = FUSE_SUPER_MAGIC; 555 return 0; 556 } 557 558 memset(&outarg, 0, sizeof(outarg)); 559 args.in_numargs = 0; 560 args.opcode = FUSE_STATFS; 561 args.nodeid = get_node_id(d_inode(dentry)); 562 args.out_numargs = 1; 563 args.out_args[0].size = sizeof(outarg); 564 args.out_args[0].value = &outarg; 565 err = fuse_simple_request(fm, &args); 566 if (!err) 567 convert_fuse_statfs(buf, &outarg.st); 568 return err; 569 } 570 571 static struct fuse_sync_bucket *fuse_sync_bucket_alloc(void) 572 { 573 struct fuse_sync_bucket *bucket; 574 575 bucket = kzalloc(sizeof(*bucket), GFP_KERNEL | __GFP_NOFAIL); 576 if (bucket) { 577 init_waitqueue_head(&bucket->waitq); 578 /* Initial active count */ 579 atomic_set(&bucket->count, 1); 580 } 581 return bucket; 582 } 583 584 static void fuse_sync_fs_writes(struct fuse_conn *fc) 585 { 586 struct fuse_sync_bucket *bucket, *new_bucket; 587 int count; 588 589 new_bucket = fuse_sync_bucket_alloc(); 590 spin_lock(&fc->lock); 591 bucket = rcu_dereference_protected(fc->curr_bucket, 1); 592 count = atomic_read(&bucket->count); 593 WARN_ON(count < 1); 594 /* No outstanding writes? */ 595 if (count == 1) { 596 spin_unlock(&fc->lock); 597 kfree(new_bucket); 598 return; 599 } 600 601 /* 602 * Completion of new bucket depends on completion of this bucket, so add 603 * one more count. 604 */ 605 atomic_inc(&new_bucket->count); 606 rcu_assign_pointer(fc->curr_bucket, new_bucket); 607 spin_unlock(&fc->lock); 608 /* 609 * Drop initial active count. At this point if all writes in this and 610 * ancestor buckets complete, the count will go to zero and this task 611 * will be woken up. 612 */ 613 atomic_dec(&bucket->count); 614 615 wait_event(bucket->waitq, atomic_read(&bucket->count) == 0); 616 617 /* Drop temp count on descendant bucket */ 618 fuse_sync_bucket_dec(new_bucket); 619 kfree_rcu(bucket, rcu); 620 } 621 622 static int fuse_sync_fs(struct super_block *sb, int wait) 623 { 624 struct fuse_mount *fm = get_fuse_mount_super(sb); 625 struct fuse_conn *fc = fm->fc; 626 struct fuse_syncfs_in inarg; 627 FUSE_ARGS(args); 628 int err; 629 630 /* 631 * Userspace cannot handle the wait == 0 case. Avoid a 632 * gratuitous roundtrip. 633 */ 634 if (!wait) 635 return 0; 636 637 /* The filesystem is being unmounted. Nothing to do. */ 638 if (!sb->s_root) 639 return 0; 640 641 if (!fc->sync_fs) 642 return 0; 643 644 fuse_sync_fs_writes(fc); 645 646 memset(&inarg, 0, sizeof(inarg)); 647 args.in_numargs = 1; 648 args.in_args[0].size = sizeof(inarg); 649 args.in_args[0].value = &inarg; 650 args.opcode = FUSE_SYNCFS; 651 args.nodeid = get_node_id(sb->s_root->d_inode); 652 args.out_numargs = 0; 653 654 err = fuse_simple_request(fm, &args); 655 if (err == -ENOSYS) { 656 fc->sync_fs = 0; 657 err = 0; 658 } 659 660 return err; 661 } 662 663 enum { 664 OPT_SOURCE, 665 OPT_SUBTYPE, 666 OPT_FD, 667 OPT_ROOTMODE, 668 OPT_USER_ID, 669 OPT_GROUP_ID, 670 OPT_DEFAULT_PERMISSIONS, 671 OPT_ALLOW_OTHER, 672 OPT_MAX_READ, 673 OPT_BLKSIZE, 674 OPT_ERR 675 }; 676 677 static const struct fs_parameter_spec fuse_fs_parameters[] = { 678 fsparam_string ("source", OPT_SOURCE), 679 fsparam_u32 ("fd", OPT_FD), 680 fsparam_u32oct ("rootmode", OPT_ROOTMODE), 681 fsparam_u32 ("user_id", OPT_USER_ID), 682 fsparam_u32 ("group_id", OPT_GROUP_ID), 683 fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS), 684 fsparam_flag ("allow_other", OPT_ALLOW_OTHER), 685 fsparam_u32 ("max_read", OPT_MAX_READ), 686 fsparam_u32 ("blksize", OPT_BLKSIZE), 687 fsparam_string ("subtype", OPT_SUBTYPE), 688 {} 689 }; 690 691 static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param) 692 { 693 struct fs_parse_result result; 694 struct fuse_fs_context *ctx = fsc->fs_private; 695 int opt; 696 697 if (fsc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { 698 /* 699 * Ignore options coming from mount(MS_REMOUNT) for backward 700 * compatibility. 701 */ 702 if (fsc->oldapi) 703 return 0; 704 705 return invalfc(fsc, "No changes allowed in reconfigure"); 706 } 707 708 opt = fs_parse(fsc, fuse_fs_parameters, param, &result); 709 if (opt < 0) 710 return opt; 711 712 switch (opt) { 713 case OPT_SOURCE: 714 if (fsc->source) 715 return invalfc(fsc, "Multiple sources specified"); 716 fsc->source = param->string; 717 param->string = NULL; 718 break; 719 720 case OPT_SUBTYPE: 721 if (ctx->subtype) 722 return invalfc(fsc, "Multiple subtypes specified"); 723 ctx->subtype = param->string; 724 param->string = NULL; 725 return 0; 726 727 case OPT_FD: 728 ctx->fd = result.uint_32; 729 ctx->fd_present = true; 730 break; 731 732 case OPT_ROOTMODE: 733 if (!fuse_valid_type(result.uint_32)) 734 return invalfc(fsc, "Invalid rootmode"); 735 ctx->rootmode = result.uint_32; 736 ctx->rootmode_present = true; 737 break; 738 739 case OPT_USER_ID: 740 ctx->user_id = make_kuid(fsc->user_ns, result.uint_32); 741 if (!uid_valid(ctx->user_id)) 742 return invalfc(fsc, "Invalid user_id"); 743 ctx->user_id_present = true; 744 break; 745 746 case OPT_GROUP_ID: 747 ctx->group_id = make_kgid(fsc->user_ns, result.uint_32); 748 if (!gid_valid(ctx->group_id)) 749 return invalfc(fsc, "Invalid group_id"); 750 ctx->group_id_present = true; 751 break; 752 753 case OPT_DEFAULT_PERMISSIONS: 754 ctx->default_permissions = true; 755 break; 756 757 case OPT_ALLOW_OTHER: 758 ctx->allow_other = true; 759 break; 760 761 case OPT_MAX_READ: 762 ctx->max_read = result.uint_32; 763 break; 764 765 case OPT_BLKSIZE: 766 if (!ctx->is_bdev) 767 return invalfc(fsc, "blksize only supported for fuseblk"); 768 ctx->blksize = result.uint_32; 769 break; 770 771 default: 772 return -EINVAL; 773 } 774 775 return 0; 776 } 777 778 static void fuse_free_fsc(struct fs_context *fsc) 779 { 780 struct fuse_fs_context *ctx = fsc->fs_private; 781 782 if (ctx) { 783 kfree(ctx->subtype); 784 kfree(ctx); 785 } 786 } 787 788 static int fuse_show_options(struct seq_file *m, struct dentry *root) 789 { 790 struct super_block *sb = root->d_sb; 791 struct fuse_conn *fc = get_fuse_conn_super(sb); 792 793 if (fc->legacy_opts_show) { 794 seq_printf(m, ",user_id=%u", 795 from_kuid_munged(fc->user_ns, fc->user_id)); 796 seq_printf(m, ",group_id=%u", 797 from_kgid_munged(fc->user_ns, fc->group_id)); 798 if (fc->default_permissions) 799 seq_puts(m, ",default_permissions"); 800 if (fc->allow_other) 801 seq_puts(m, ",allow_other"); 802 if (fc->max_read != ~0) 803 seq_printf(m, ",max_read=%u", fc->max_read); 804 if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) 805 seq_printf(m, ",blksize=%lu", sb->s_blocksize); 806 } 807 #ifdef CONFIG_FUSE_DAX 808 if (fc->dax_mode == FUSE_DAX_ALWAYS) 809 seq_puts(m, ",dax=always"); 810 else if (fc->dax_mode == FUSE_DAX_NEVER) 811 seq_puts(m, ",dax=never"); 812 else if (fc->dax_mode == FUSE_DAX_INODE_USER) 813 seq_puts(m, ",dax=inode"); 814 #endif 815 816 return 0; 817 } 818 819 static void fuse_iqueue_init(struct fuse_iqueue *fiq, 820 const struct fuse_iqueue_ops *ops, 821 void *priv) 822 { 823 memset(fiq, 0, sizeof(struct fuse_iqueue)); 824 spin_lock_init(&fiq->lock); 825 init_waitqueue_head(&fiq->waitq); 826 INIT_LIST_HEAD(&fiq->pending); 827 INIT_LIST_HEAD(&fiq->interrupts); 828 fiq->forget_list_tail = &fiq->forget_list_head; 829 fiq->connected = 1; 830 fiq->ops = ops; 831 fiq->priv = priv; 832 } 833 834 static void fuse_pqueue_init(struct fuse_pqueue *fpq) 835 { 836 unsigned int i; 837 838 spin_lock_init(&fpq->lock); 839 for (i = 0; i < FUSE_PQ_HASH_SIZE; i++) 840 INIT_LIST_HEAD(&fpq->processing[i]); 841 INIT_LIST_HEAD(&fpq->io); 842 fpq->connected = 1; 843 } 844 845 void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm, 846 struct user_namespace *user_ns, 847 const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv) 848 { 849 memset(fc, 0, sizeof(*fc)); 850 spin_lock_init(&fc->lock); 851 spin_lock_init(&fc->bg_lock); 852 init_rwsem(&fc->killsb); 853 refcount_set(&fc->count, 1); 854 atomic_set(&fc->dev_count, 1); 855 init_waitqueue_head(&fc->blocked_waitq); 856 fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv); 857 INIT_LIST_HEAD(&fc->bg_queue); 858 INIT_LIST_HEAD(&fc->entry); 859 INIT_LIST_HEAD(&fc->devices); 860 atomic_set(&fc->num_waiting, 0); 861 fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND; 862 fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD; 863 atomic64_set(&fc->khctr, 0); 864 fc->polled_files = RB_ROOT; 865 fc->blocked = 0; 866 fc->initialized = 0; 867 fc->connected = 1; 868 atomic64_set(&fc->attr_version, 1); 869 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); 870 fc->pid_ns = get_pid_ns(task_active_pid_ns(current)); 871 fc->user_ns = get_user_ns(user_ns); 872 fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; 873 fc->max_pages_limit = FUSE_MAX_MAX_PAGES; 874 875 INIT_LIST_HEAD(&fc->mounts); 876 list_add(&fm->fc_entry, &fc->mounts); 877 fm->fc = fc; 878 } 879 EXPORT_SYMBOL_GPL(fuse_conn_init); 880 881 void fuse_conn_put(struct fuse_conn *fc) 882 { 883 if (refcount_dec_and_test(&fc->count)) { 884 struct fuse_iqueue *fiq = &fc->iq; 885 struct fuse_sync_bucket *bucket; 886 887 if (IS_ENABLED(CONFIG_FUSE_DAX)) 888 fuse_dax_conn_free(fc); 889 if (fiq->ops->release) 890 fiq->ops->release(fiq); 891 put_pid_ns(fc->pid_ns); 892 put_user_ns(fc->user_ns); 893 bucket = rcu_dereference_protected(fc->curr_bucket, 1); 894 if (bucket) { 895 WARN_ON(atomic_read(&bucket->count) != 1); 896 kfree(bucket); 897 } 898 fc->release(fc); 899 } 900 } 901 EXPORT_SYMBOL_GPL(fuse_conn_put); 902 903 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) 904 { 905 refcount_inc(&fc->count); 906 return fc; 907 } 908 EXPORT_SYMBOL_GPL(fuse_conn_get); 909 910 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode) 911 { 912 struct fuse_attr attr; 913 memset(&attr, 0, sizeof(attr)); 914 915 attr.mode = mode; 916 attr.ino = FUSE_ROOT_ID; 917 attr.nlink = 1; 918 return fuse_iget(sb, 1, 0, &attr, 0, 0); 919 } 920 921 struct fuse_inode_handle { 922 u64 nodeid; 923 u32 generation; 924 }; 925 926 static struct dentry *fuse_get_dentry(struct super_block *sb, 927 struct fuse_inode_handle *handle) 928 { 929 struct fuse_conn *fc = get_fuse_conn_super(sb); 930 struct inode *inode; 931 struct dentry *entry; 932 int err = -ESTALE; 933 934 if (handle->nodeid == 0) 935 goto out_err; 936 937 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid); 938 if (!inode) { 939 struct fuse_entry_out outarg; 940 const struct qstr name = QSTR_INIT(".", 1); 941 942 if (!fc->export_support) 943 goto out_err; 944 945 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg, 946 &inode); 947 if (err && err != -ENOENT) 948 goto out_err; 949 if (err || !inode) { 950 err = -ESTALE; 951 goto out_err; 952 } 953 err = -EIO; 954 if (get_node_id(inode) != handle->nodeid) 955 goto out_iput; 956 } 957 err = -ESTALE; 958 if (inode->i_generation != handle->generation) 959 goto out_iput; 960 961 entry = d_obtain_alias(inode); 962 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) 963 fuse_invalidate_entry_cache(entry); 964 965 return entry; 966 967 out_iput: 968 iput(inode); 969 out_err: 970 return ERR_PTR(err); 971 } 972 973 static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len, 974 struct inode *parent) 975 { 976 int len = parent ? 6 : 3; 977 u64 nodeid; 978 u32 generation; 979 980 if (*max_len < len) { 981 *max_len = len; 982 return FILEID_INVALID; 983 } 984 985 nodeid = get_fuse_inode(inode)->nodeid; 986 generation = inode->i_generation; 987 988 fh[0] = (u32)(nodeid >> 32); 989 fh[1] = (u32)(nodeid & 0xffffffff); 990 fh[2] = generation; 991 992 if (parent) { 993 nodeid = get_fuse_inode(parent)->nodeid; 994 generation = parent->i_generation; 995 996 fh[3] = (u32)(nodeid >> 32); 997 fh[4] = (u32)(nodeid & 0xffffffff); 998 fh[5] = generation; 999 } 1000 1001 *max_len = len; 1002 return parent ? 0x82 : 0x81; 1003 } 1004 1005 static struct dentry *fuse_fh_to_dentry(struct super_block *sb, 1006 struct fid *fid, int fh_len, int fh_type) 1007 { 1008 struct fuse_inode_handle handle; 1009 1010 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3) 1011 return NULL; 1012 1013 handle.nodeid = (u64) fid->raw[0] << 32; 1014 handle.nodeid |= (u64) fid->raw[1]; 1015 handle.generation = fid->raw[2]; 1016 return fuse_get_dentry(sb, &handle); 1017 } 1018 1019 static struct dentry *fuse_fh_to_parent(struct super_block *sb, 1020 struct fid *fid, int fh_len, int fh_type) 1021 { 1022 struct fuse_inode_handle parent; 1023 1024 if (fh_type != 0x82 || fh_len < 6) 1025 return NULL; 1026 1027 parent.nodeid = (u64) fid->raw[3] << 32; 1028 parent.nodeid |= (u64) fid->raw[4]; 1029 parent.generation = fid->raw[5]; 1030 return fuse_get_dentry(sb, &parent); 1031 } 1032 1033 static struct dentry *fuse_get_parent(struct dentry *child) 1034 { 1035 struct inode *child_inode = d_inode(child); 1036 struct fuse_conn *fc = get_fuse_conn(child_inode); 1037 struct inode *inode; 1038 struct dentry *parent; 1039 struct fuse_entry_out outarg; 1040 int err; 1041 1042 if (!fc->export_support) 1043 return ERR_PTR(-ESTALE); 1044 1045 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode), 1046 &dotdot_name, &outarg, &inode); 1047 if (err) { 1048 if (err == -ENOENT) 1049 return ERR_PTR(-ESTALE); 1050 return ERR_PTR(err); 1051 } 1052 1053 parent = d_obtain_alias(inode); 1054 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) 1055 fuse_invalidate_entry_cache(parent); 1056 1057 return parent; 1058 } 1059 1060 static const struct export_operations fuse_export_operations = { 1061 .fh_to_dentry = fuse_fh_to_dentry, 1062 .fh_to_parent = fuse_fh_to_parent, 1063 .encode_fh = fuse_encode_fh, 1064 .get_parent = fuse_get_parent, 1065 }; 1066 1067 static const struct super_operations fuse_super_operations = { 1068 .alloc_inode = fuse_alloc_inode, 1069 .free_inode = fuse_free_inode, 1070 .evict_inode = fuse_evict_inode, 1071 .write_inode = fuse_write_inode, 1072 .drop_inode = generic_delete_inode, 1073 .umount_begin = fuse_umount_begin, 1074 .statfs = fuse_statfs, 1075 .sync_fs = fuse_sync_fs, 1076 .show_options = fuse_show_options, 1077 }; 1078 1079 static void sanitize_global_limit(unsigned *limit) 1080 { 1081 /* 1082 * The default maximum number of async requests is calculated to consume 1083 * 1/2^13 of the total memory, assuming 392 bytes per request. 1084 */ 1085 if (*limit == 0) 1086 *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392; 1087 1088 if (*limit >= 1 << 16) 1089 *limit = (1 << 16) - 1; 1090 } 1091 1092 static int set_global_limit(const char *val, const struct kernel_param *kp) 1093 { 1094 int rv; 1095 1096 rv = param_set_uint(val, kp); 1097 if (rv) 1098 return rv; 1099 1100 sanitize_global_limit((unsigned *)kp->arg); 1101 1102 return 0; 1103 } 1104 1105 static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) 1106 { 1107 int cap_sys_admin = capable(CAP_SYS_ADMIN); 1108 1109 if (arg->minor < 13) 1110 return; 1111 1112 sanitize_global_limit(&max_user_bgreq); 1113 sanitize_global_limit(&max_user_congthresh); 1114 1115 spin_lock(&fc->bg_lock); 1116 if (arg->max_background) { 1117 fc->max_background = arg->max_background; 1118 1119 if (!cap_sys_admin && fc->max_background > max_user_bgreq) 1120 fc->max_background = max_user_bgreq; 1121 } 1122 if (arg->congestion_threshold) { 1123 fc->congestion_threshold = arg->congestion_threshold; 1124 1125 if (!cap_sys_admin && 1126 fc->congestion_threshold > max_user_congthresh) 1127 fc->congestion_threshold = max_user_congthresh; 1128 } 1129 spin_unlock(&fc->bg_lock); 1130 } 1131 1132 struct fuse_init_args { 1133 struct fuse_args args; 1134 struct fuse_init_in in; 1135 struct fuse_init_out out; 1136 }; 1137 1138 static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args, 1139 int error) 1140 { 1141 struct fuse_conn *fc = fm->fc; 1142 struct fuse_init_args *ia = container_of(args, typeof(*ia), args); 1143 struct fuse_init_out *arg = &ia->out; 1144 bool ok = true; 1145 1146 if (error || arg->major != FUSE_KERNEL_VERSION) 1147 ok = false; 1148 else { 1149 unsigned long ra_pages; 1150 1151 process_init_limits(fc, arg); 1152 1153 if (arg->minor >= 6) { 1154 u64 flags = arg->flags; 1155 1156 if (flags & FUSE_INIT_EXT) 1157 flags |= (u64) arg->flags2 << 32; 1158 1159 ra_pages = arg->max_readahead / PAGE_SIZE; 1160 if (flags & FUSE_ASYNC_READ) 1161 fc->async_read = 1; 1162 if (!(flags & FUSE_POSIX_LOCKS)) 1163 fc->no_lock = 1; 1164 if (arg->minor >= 17) { 1165 if (!(flags & FUSE_FLOCK_LOCKS)) 1166 fc->no_flock = 1; 1167 } else { 1168 if (!(flags & FUSE_POSIX_LOCKS)) 1169 fc->no_flock = 1; 1170 } 1171 if (flags & FUSE_ATOMIC_O_TRUNC) 1172 fc->atomic_o_trunc = 1; 1173 if (arg->minor >= 9) { 1174 /* LOOKUP has dependency on proto version */ 1175 if (flags & FUSE_EXPORT_SUPPORT) 1176 fc->export_support = 1; 1177 } 1178 if (flags & FUSE_BIG_WRITES) 1179 fc->big_writes = 1; 1180 if (flags & FUSE_DONT_MASK) 1181 fc->dont_mask = 1; 1182 if (flags & FUSE_AUTO_INVAL_DATA) 1183 fc->auto_inval_data = 1; 1184 else if (flags & FUSE_EXPLICIT_INVAL_DATA) 1185 fc->explicit_inval_data = 1; 1186 if (flags & FUSE_DO_READDIRPLUS) { 1187 fc->do_readdirplus = 1; 1188 if (flags & FUSE_READDIRPLUS_AUTO) 1189 fc->readdirplus_auto = 1; 1190 } 1191 if (flags & FUSE_ASYNC_DIO) 1192 fc->async_dio = 1; 1193 if (flags & FUSE_WRITEBACK_CACHE) 1194 fc->writeback_cache = 1; 1195 if (flags & FUSE_PARALLEL_DIROPS) 1196 fc->parallel_dirops = 1; 1197 if (flags & FUSE_HANDLE_KILLPRIV) 1198 fc->handle_killpriv = 1; 1199 if (arg->time_gran && arg->time_gran <= 1000000000) 1200 fm->sb->s_time_gran = arg->time_gran; 1201 if ((flags & FUSE_POSIX_ACL)) { 1202 fc->default_permissions = 1; 1203 fc->posix_acl = 1; 1204 } 1205 if (flags & FUSE_CACHE_SYMLINKS) 1206 fc->cache_symlinks = 1; 1207 if (flags & FUSE_ABORT_ERROR) 1208 fc->abort_err = 1; 1209 if (flags & FUSE_MAX_PAGES) { 1210 fc->max_pages = 1211 min_t(unsigned int, fc->max_pages_limit, 1212 max_t(unsigned int, arg->max_pages, 1)); 1213 } 1214 if (IS_ENABLED(CONFIG_FUSE_DAX)) { 1215 if (flags & FUSE_MAP_ALIGNMENT && 1216 !fuse_dax_check_alignment(fc, arg->map_alignment)) { 1217 ok = false; 1218 } 1219 if (flags & FUSE_HAS_INODE_DAX) 1220 fc->inode_dax = 1; 1221 } 1222 if (flags & FUSE_HANDLE_KILLPRIV_V2) { 1223 fc->handle_killpriv_v2 = 1; 1224 fm->sb->s_flags |= SB_NOSEC; 1225 } 1226 if (flags & FUSE_SETXATTR_EXT) 1227 fc->setxattr_ext = 1; 1228 if (flags & FUSE_SECURITY_CTX) 1229 fc->init_security = 1; 1230 if (flags & FUSE_CREATE_SUPP_GROUP) 1231 fc->create_supp_group = 1; 1232 if (flags & FUSE_DIRECT_IO_RELAX) 1233 fc->direct_io_relax = 1; 1234 } else { 1235 ra_pages = fc->max_read / PAGE_SIZE; 1236 fc->no_lock = 1; 1237 fc->no_flock = 1; 1238 } 1239 1240 fm->sb->s_bdi->ra_pages = 1241 min(fm->sb->s_bdi->ra_pages, ra_pages); 1242 fc->minor = arg->minor; 1243 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; 1244 fc->max_write = max_t(unsigned, 4096, fc->max_write); 1245 fc->conn_init = 1; 1246 } 1247 kfree(ia); 1248 1249 if (!ok) { 1250 fc->conn_init = 0; 1251 fc->conn_error = 1; 1252 } 1253 1254 fuse_set_initialized(fc); 1255 wake_up_all(&fc->blocked_waitq); 1256 } 1257 1258 void fuse_send_init(struct fuse_mount *fm) 1259 { 1260 struct fuse_init_args *ia; 1261 u64 flags; 1262 1263 ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL); 1264 1265 ia->in.major = FUSE_KERNEL_VERSION; 1266 ia->in.minor = FUSE_KERNEL_MINOR_VERSION; 1267 ia->in.max_readahead = fm->sb->s_bdi->ra_pages * PAGE_SIZE; 1268 flags = 1269 FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC | 1270 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | 1271 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | 1272 FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | 1273 FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | 1274 FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | 1275 FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | 1276 FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS | 1277 FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | 1278 FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT | 1279 FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP | 1280 FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_RELAX; 1281 #ifdef CONFIG_FUSE_DAX 1282 if (fm->fc->dax) 1283 flags |= FUSE_MAP_ALIGNMENT; 1284 if (fuse_is_inode_dax_mode(fm->fc->dax_mode)) 1285 flags |= FUSE_HAS_INODE_DAX; 1286 #endif 1287 if (fm->fc->auto_submounts) 1288 flags |= FUSE_SUBMOUNTS; 1289 1290 ia->in.flags = flags; 1291 ia->in.flags2 = flags >> 32; 1292 1293 ia->args.opcode = FUSE_INIT; 1294 ia->args.in_numargs = 1; 1295 ia->args.in_args[0].size = sizeof(ia->in); 1296 ia->args.in_args[0].value = &ia->in; 1297 ia->args.out_numargs = 1; 1298 /* Variable length argument used for backward compatibility 1299 with interface version < 7.5. Rest of init_out is zeroed 1300 by do_get_request(), so a short reply is not a problem */ 1301 ia->args.out_argvar = true; 1302 ia->args.out_args[0].size = sizeof(ia->out); 1303 ia->args.out_args[0].value = &ia->out; 1304 ia->args.force = true; 1305 ia->args.nocreds = true; 1306 ia->args.end = process_init_reply; 1307 1308 if (fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0) 1309 process_init_reply(fm, &ia->args, -ENOTCONN); 1310 } 1311 EXPORT_SYMBOL_GPL(fuse_send_init); 1312 1313 void fuse_free_conn(struct fuse_conn *fc) 1314 { 1315 WARN_ON(!list_empty(&fc->devices)); 1316 kfree_rcu(fc, rcu); 1317 } 1318 EXPORT_SYMBOL_GPL(fuse_free_conn); 1319 1320 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) 1321 { 1322 int err; 1323 char *suffix = ""; 1324 1325 if (sb->s_bdev) { 1326 suffix = "-fuseblk"; 1327 /* 1328 * sb->s_bdi points to blkdev's bdi however we want to redirect 1329 * it to our private bdi... 1330 */ 1331 bdi_put(sb->s_bdi); 1332 sb->s_bdi = &noop_backing_dev_info; 1333 } 1334 err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev), 1335 MINOR(fc->dev), suffix); 1336 if (err) 1337 return err; 1338 1339 /* fuse does it's own writeback accounting */ 1340 sb->s_bdi->capabilities &= ~BDI_CAP_WRITEBACK_ACCT; 1341 sb->s_bdi->capabilities |= BDI_CAP_STRICTLIMIT; 1342 1343 /* 1344 * For a single fuse filesystem use max 1% of dirty + 1345 * writeback threshold. 1346 * 1347 * This gives about 1M of write buffer for memory maps on a 1348 * machine with 1G and 10% dirty_ratio, which should be more 1349 * than enough. 1350 * 1351 * Privileged users can raise it by writing to 1352 * 1353 * /sys/class/bdi/<bdi>/max_ratio 1354 */ 1355 bdi_set_max_ratio(sb->s_bdi, 1); 1356 1357 return 0; 1358 } 1359 1360 struct fuse_dev *fuse_dev_alloc(void) 1361 { 1362 struct fuse_dev *fud; 1363 struct list_head *pq; 1364 1365 fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL); 1366 if (!fud) 1367 return NULL; 1368 1369 pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL); 1370 if (!pq) { 1371 kfree(fud); 1372 return NULL; 1373 } 1374 1375 fud->pq.processing = pq; 1376 fuse_pqueue_init(&fud->pq); 1377 1378 return fud; 1379 } 1380 EXPORT_SYMBOL_GPL(fuse_dev_alloc); 1381 1382 void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc) 1383 { 1384 fud->fc = fuse_conn_get(fc); 1385 spin_lock(&fc->lock); 1386 list_add_tail(&fud->entry, &fc->devices); 1387 spin_unlock(&fc->lock); 1388 } 1389 EXPORT_SYMBOL_GPL(fuse_dev_install); 1390 1391 struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc) 1392 { 1393 struct fuse_dev *fud; 1394 1395 fud = fuse_dev_alloc(); 1396 if (!fud) 1397 return NULL; 1398 1399 fuse_dev_install(fud, fc); 1400 return fud; 1401 } 1402 EXPORT_SYMBOL_GPL(fuse_dev_alloc_install); 1403 1404 void fuse_dev_free(struct fuse_dev *fud) 1405 { 1406 struct fuse_conn *fc = fud->fc; 1407 1408 if (fc) { 1409 spin_lock(&fc->lock); 1410 list_del(&fud->entry); 1411 spin_unlock(&fc->lock); 1412 1413 fuse_conn_put(fc); 1414 } 1415 kfree(fud->pq.processing); 1416 kfree(fud); 1417 } 1418 EXPORT_SYMBOL_GPL(fuse_dev_free); 1419 1420 static void fuse_fill_attr_from_inode(struct fuse_attr *attr, 1421 const struct fuse_inode *fi) 1422 { 1423 struct timespec64 atime = inode_get_atime(&fi->inode); 1424 struct timespec64 mtime = inode_get_mtime(&fi->inode); 1425 struct timespec64 ctime = inode_get_ctime(&fi->inode); 1426 1427 *attr = (struct fuse_attr){ 1428 .ino = fi->inode.i_ino, 1429 .size = fi->inode.i_size, 1430 .blocks = fi->inode.i_blocks, 1431 .atime = atime.tv_sec, 1432 .mtime = mtime.tv_sec, 1433 .ctime = ctime.tv_sec, 1434 .atimensec = atime.tv_nsec, 1435 .mtimensec = mtime.tv_nsec, 1436 .ctimensec = ctime.tv_nsec, 1437 .mode = fi->inode.i_mode, 1438 .nlink = fi->inode.i_nlink, 1439 .uid = fi->inode.i_uid.val, 1440 .gid = fi->inode.i_gid.val, 1441 .rdev = fi->inode.i_rdev, 1442 .blksize = 1u << fi->inode.i_blkbits, 1443 }; 1444 } 1445 1446 static void fuse_sb_defaults(struct super_block *sb) 1447 { 1448 sb->s_magic = FUSE_SUPER_MAGIC; 1449 sb->s_op = &fuse_super_operations; 1450 sb->s_xattr = fuse_xattr_handlers; 1451 sb->s_maxbytes = MAX_LFS_FILESIZE; 1452 sb->s_time_gran = 1; 1453 sb->s_export_op = &fuse_export_operations; 1454 sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE; 1455 if (sb->s_user_ns != &init_user_ns) 1456 sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER; 1457 sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION); 1458 } 1459 1460 static int fuse_fill_super_submount(struct super_block *sb, 1461 struct fuse_inode *parent_fi) 1462 { 1463 struct fuse_mount *fm = get_fuse_mount_super(sb); 1464 struct super_block *parent_sb = parent_fi->inode.i_sb; 1465 struct fuse_attr root_attr; 1466 struct inode *root; 1467 1468 fuse_sb_defaults(sb); 1469 fm->sb = sb; 1470 1471 WARN_ON(sb->s_bdi != &noop_backing_dev_info); 1472 sb->s_bdi = bdi_get(parent_sb->s_bdi); 1473 1474 sb->s_xattr = parent_sb->s_xattr; 1475 sb->s_time_gran = parent_sb->s_time_gran; 1476 sb->s_blocksize = parent_sb->s_blocksize; 1477 sb->s_blocksize_bits = parent_sb->s_blocksize_bits; 1478 sb->s_subtype = kstrdup(parent_sb->s_subtype, GFP_KERNEL); 1479 if (parent_sb->s_subtype && !sb->s_subtype) 1480 return -ENOMEM; 1481 1482 fuse_fill_attr_from_inode(&root_attr, parent_fi); 1483 root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0); 1484 /* 1485 * This inode is just a duplicate, so it is not looked up and 1486 * its nlookup should not be incremented. fuse_iget() does 1487 * that, though, so undo it here. 1488 */ 1489 get_fuse_inode(root)->nlookup--; 1490 sb->s_d_op = &fuse_dentry_operations; 1491 sb->s_root = d_make_root(root); 1492 if (!sb->s_root) 1493 return -ENOMEM; 1494 1495 return 0; 1496 } 1497 1498 /* Filesystem context private data holds the FUSE inode of the mount point */ 1499 static int fuse_get_tree_submount(struct fs_context *fsc) 1500 { 1501 struct fuse_mount *fm; 1502 struct fuse_inode *mp_fi = fsc->fs_private; 1503 struct fuse_conn *fc = get_fuse_conn(&mp_fi->inode); 1504 struct super_block *sb; 1505 int err; 1506 1507 fm = kzalloc(sizeof(struct fuse_mount), GFP_KERNEL); 1508 if (!fm) 1509 return -ENOMEM; 1510 1511 fm->fc = fuse_conn_get(fc); 1512 fsc->s_fs_info = fm; 1513 sb = sget_fc(fsc, NULL, set_anon_super_fc); 1514 if (fsc->s_fs_info) 1515 fuse_mount_destroy(fm); 1516 if (IS_ERR(sb)) 1517 return PTR_ERR(sb); 1518 1519 /* Initialize superblock, making @mp_fi its root */ 1520 err = fuse_fill_super_submount(sb, mp_fi); 1521 if (err) { 1522 deactivate_locked_super(sb); 1523 return err; 1524 } 1525 1526 down_write(&fc->killsb); 1527 list_add_tail(&fm->fc_entry, &fc->mounts); 1528 up_write(&fc->killsb); 1529 1530 sb->s_flags |= SB_ACTIVE; 1531 fsc->root = dget(sb->s_root); 1532 1533 return 0; 1534 } 1535 1536 static const struct fs_context_operations fuse_context_submount_ops = { 1537 .get_tree = fuse_get_tree_submount, 1538 }; 1539 1540 int fuse_init_fs_context_submount(struct fs_context *fsc) 1541 { 1542 fsc->ops = &fuse_context_submount_ops; 1543 return 0; 1544 } 1545 EXPORT_SYMBOL_GPL(fuse_init_fs_context_submount); 1546 1547 int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) 1548 { 1549 struct fuse_dev *fud = NULL; 1550 struct fuse_mount *fm = get_fuse_mount_super(sb); 1551 struct fuse_conn *fc = fm->fc; 1552 struct inode *root; 1553 struct dentry *root_dentry; 1554 int err; 1555 1556 err = -EINVAL; 1557 if (sb->s_flags & SB_MANDLOCK) 1558 goto err; 1559 1560 rcu_assign_pointer(fc->curr_bucket, fuse_sync_bucket_alloc()); 1561 fuse_sb_defaults(sb); 1562 1563 if (ctx->is_bdev) { 1564 #ifdef CONFIG_BLOCK 1565 err = -EINVAL; 1566 if (!sb_set_blocksize(sb, ctx->blksize)) 1567 goto err; 1568 #endif 1569 } else { 1570 sb->s_blocksize = PAGE_SIZE; 1571 sb->s_blocksize_bits = PAGE_SHIFT; 1572 } 1573 1574 sb->s_subtype = ctx->subtype; 1575 ctx->subtype = NULL; 1576 if (IS_ENABLED(CONFIG_FUSE_DAX)) { 1577 err = fuse_dax_conn_alloc(fc, ctx->dax_mode, ctx->dax_dev); 1578 if (err) 1579 goto err; 1580 } 1581 1582 if (ctx->fudptr) { 1583 err = -ENOMEM; 1584 fud = fuse_dev_alloc_install(fc); 1585 if (!fud) 1586 goto err_free_dax; 1587 } 1588 1589 fc->dev = sb->s_dev; 1590 fm->sb = sb; 1591 err = fuse_bdi_init(fc, sb); 1592 if (err) 1593 goto err_dev_free; 1594 1595 /* Handle umasking inside the fuse code */ 1596 if (sb->s_flags & SB_POSIXACL) 1597 fc->dont_mask = 1; 1598 sb->s_flags |= SB_POSIXACL; 1599 1600 fc->default_permissions = ctx->default_permissions; 1601 fc->allow_other = ctx->allow_other; 1602 fc->user_id = ctx->user_id; 1603 fc->group_id = ctx->group_id; 1604 fc->legacy_opts_show = ctx->legacy_opts_show; 1605 fc->max_read = max_t(unsigned int, 4096, ctx->max_read); 1606 fc->destroy = ctx->destroy; 1607 fc->no_control = ctx->no_control; 1608 fc->no_force_umount = ctx->no_force_umount; 1609 1610 err = -ENOMEM; 1611 root = fuse_get_root_inode(sb, ctx->rootmode); 1612 sb->s_d_op = &fuse_root_dentry_operations; 1613 root_dentry = d_make_root(root); 1614 if (!root_dentry) 1615 goto err_dev_free; 1616 /* Root dentry doesn't have .d_revalidate */ 1617 sb->s_d_op = &fuse_dentry_operations; 1618 1619 mutex_lock(&fuse_mutex); 1620 err = -EINVAL; 1621 if (ctx->fudptr && *ctx->fudptr) 1622 goto err_unlock; 1623 1624 err = fuse_ctl_add_conn(fc); 1625 if (err) 1626 goto err_unlock; 1627 1628 list_add_tail(&fc->entry, &fuse_conn_list); 1629 sb->s_root = root_dentry; 1630 if (ctx->fudptr) 1631 *ctx->fudptr = fud; 1632 mutex_unlock(&fuse_mutex); 1633 return 0; 1634 1635 err_unlock: 1636 mutex_unlock(&fuse_mutex); 1637 dput(root_dentry); 1638 err_dev_free: 1639 if (fud) 1640 fuse_dev_free(fud); 1641 err_free_dax: 1642 if (IS_ENABLED(CONFIG_FUSE_DAX)) 1643 fuse_dax_conn_free(fc); 1644 err: 1645 return err; 1646 } 1647 EXPORT_SYMBOL_GPL(fuse_fill_super_common); 1648 1649 static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) 1650 { 1651 struct fuse_fs_context *ctx = fsc->fs_private; 1652 int err; 1653 1654 if (!ctx->file || !ctx->rootmode_present || 1655 !ctx->user_id_present || !ctx->group_id_present) 1656 return -EINVAL; 1657 1658 /* 1659 * Require mount to happen from the same user namespace which 1660 * opened /dev/fuse to prevent potential attacks. 1661 */ 1662 if ((ctx->file->f_op != &fuse_dev_operations) || 1663 (ctx->file->f_cred->user_ns != sb->s_user_ns)) 1664 return -EINVAL; 1665 ctx->fudptr = &ctx->file->private_data; 1666 1667 err = fuse_fill_super_common(sb, ctx); 1668 if (err) 1669 return err; 1670 /* file->private_data shall be visible on all CPUs after this */ 1671 smp_mb(); 1672 fuse_send_init(get_fuse_mount_super(sb)); 1673 return 0; 1674 } 1675 1676 /* 1677 * This is the path where user supplied an already initialized fuse dev. In 1678 * this case never create a new super if the old one is gone. 1679 */ 1680 static int fuse_set_no_super(struct super_block *sb, struct fs_context *fsc) 1681 { 1682 return -ENOTCONN; 1683 } 1684 1685 static int fuse_test_super(struct super_block *sb, struct fs_context *fsc) 1686 { 1687 1688 return fsc->sget_key == get_fuse_conn_super(sb); 1689 } 1690 1691 static int fuse_get_tree(struct fs_context *fsc) 1692 { 1693 struct fuse_fs_context *ctx = fsc->fs_private; 1694 struct fuse_dev *fud; 1695 struct fuse_conn *fc; 1696 struct fuse_mount *fm; 1697 struct super_block *sb; 1698 int err; 1699 1700 fc = kmalloc(sizeof(*fc), GFP_KERNEL); 1701 if (!fc) 1702 return -ENOMEM; 1703 1704 fm = kzalloc(sizeof(*fm), GFP_KERNEL); 1705 if (!fm) { 1706 kfree(fc); 1707 return -ENOMEM; 1708 } 1709 1710 fuse_conn_init(fc, fm, fsc->user_ns, &fuse_dev_fiq_ops, NULL); 1711 fc->release = fuse_free_conn; 1712 1713 fsc->s_fs_info = fm; 1714 1715 if (ctx->fd_present) 1716 ctx->file = fget(ctx->fd); 1717 1718 if (IS_ENABLED(CONFIG_BLOCK) && ctx->is_bdev) { 1719 err = get_tree_bdev(fsc, fuse_fill_super); 1720 goto out; 1721 } 1722 /* 1723 * While block dev mount can be initialized with a dummy device fd 1724 * (found by device name), normal fuse mounts can't 1725 */ 1726 err = -EINVAL; 1727 if (!ctx->file) 1728 goto out; 1729 1730 /* 1731 * Allow creating a fuse mount with an already initialized fuse 1732 * connection 1733 */ 1734 fud = READ_ONCE(ctx->file->private_data); 1735 if (ctx->file->f_op == &fuse_dev_operations && fud) { 1736 fsc->sget_key = fud->fc; 1737 sb = sget_fc(fsc, fuse_test_super, fuse_set_no_super); 1738 err = PTR_ERR_OR_ZERO(sb); 1739 if (!IS_ERR(sb)) 1740 fsc->root = dget(sb->s_root); 1741 } else { 1742 err = get_tree_nodev(fsc, fuse_fill_super); 1743 } 1744 out: 1745 if (fsc->s_fs_info) 1746 fuse_mount_destroy(fm); 1747 if (ctx->file) 1748 fput(ctx->file); 1749 return err; 1750 } 1751 1752 static const struct fs_context_operations fuse_context_ops = { 1753 .free = fuse_free_fsc, 1754 .parse_param = fuse_parse_param, 1755 .reconfigure = fuse_reconfigure, 1756 .get_tree = fuse_get_tree, 1757 }; 1758 1759 /* 1760 * Set up the filesystem mount context. 1761 */ 1762 static int fuse_init_fs_context(struct fs_context *fsc) 1763 { 1764 struct fuse_fs_context *ctx; 1765 1766 ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL); 1767 if (!ctx) 1768 return -ENOMEM; 1769 1770 ctx->max_read = ~0; 1771 ctx->blksize = FUSE_DEFAULT_BLKSIZE; 1772 ctx->legacy_opts_show = true; 1773 1774 #ifdef CONFIG_BLOCK 1775 if (fsc->fs_type == &fuseblk_fs_type) { 1776 ctx->is_bdev = true; 1777 ctx->destroy = true; 1778 } 1779 #endif 1780 1781 fsc->fs_private = ctx; 1782 fsc->ops = &fuse_context_ops; 1783 return 0; 1784 } 1785 1786 bool fuse_mount_remove(struct fuse_mount *fm) 1787 { 1788 struct fuse_conn *fc = fm->fc; 1789 bool last = false; 1790 1791 down_write(&fc->killsb); 1792 list_del_init(&fm->fc_entry); 1793 if (list_empty(&fc->mounts)) 1794 last = true; 1795 up_write(&fc->killsb); 1796 1797 return last; 1798 } 1799 EXPORT_SYMBOL_GPL(fuse_mount_remove); 1800 1801 void fuse_conn_destroy(struct fuse_mount *fm) 1802 { 1803 struct fuse_conn *fc = fm->fc; 1804 1805 if (fc->destroy) 1806 fuse_send_destroy(fm); 1807 1808 fuse_abort_conn(fc); 1809 fuse_wait_aborted(fc); 1810 1811 if (!list_empty(&fc->entry)) { 1812 mutex_lock(&fuse_mutex); 1813 list_del(&fc->entry); 1814 fuse_ctl_remove_conn(fc); 1815 mutex_unlock(&fuse_mutex); 1816 } 1817 } 1818 EXPORT_SYMBOL_GPL(fuse_conn_destroy); 1819 1820 static void fuse_sb_destroy(struct super_block *sb) 1821 { 1822 struct fuse_mount *fm = get_fuse_mount_super(sb); 1823 bool last; 1824 1825 if (sb->s_root) { 1826 last = fuse_mount_remove(fm); 1827 if (last) 1828 fuse_conn_destroy(fm); 1829 } 1830 } 1831 1832 void fuse_mount_destroy(struct fuse_mount *fm) 1833 { 1834 fuse_conn_put(fm->fc); 1835 kfree(fm); 1836 } 1837 EXPORT_SYMBOL(fuse_mount_destroy); 1838 1839 static void fuse_kill_sb_anon(struct super_block *sb) 1840 { 1841 fuse_sb_destroy(sb); 1842 kill_anon_super(sb); 1843 fuse_mount_destroy(get_fuse_mount_super(sb)); 1844 } 1845 1846 static struct file_system_type fuse_fs_type = { 1847 .owner = THIS_MODULE, 1848 .name = "fuse", 1849 .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT, 1850 .init_fs_context = fuse_init_fs_context, 1851 .parameters = fuse_fs_parameters, 1852 .kill_sb = fuse_kill_sb_anon, 1853 }; 1854 MODULE_ALIAS_FS("fuse"); 1855 1856 #ifdef CONFIG_BLOCK 1857 static void fuse_kill_sb_blk(struct super_block *sb) 1858 { 1859 fuse_sb_destroy(sb); 1860 kill_block_super(sb); 1861 fuse_mount_destroy(get_fuse_mount_super(sb)); 1862 } 1863 1864 static struct file_system_type fuseblk_fs_type = { 1865 .owner = THIS_MODULE, 1866 .name = "fuseblk", 1867 .init_fs_context = fuse_init_fs_context, 1868 .parameters = fuse_fs_parameters, 1869 .kill_sb = fuse_kill_sb_blk, 1870 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE, 1871 }; 1872 MODULE_ALIAS_FS("fuseblk"); 1873 1874 static inline int register_fuseblk(void) 1875 { 1876 return register_filesystem(&fuseblk_fs_type); 1877 } 1878 1879 static inline void unregister_fuseblk(void) 1880 { 1881 unregister_filesystem(&fuseblk_fs_type); 1882 } 1883 #else 1884 static inline int register_fuseblk(void) 1885 { 1886 return 0; 1887 } 1888 1889 static inline void unregister_fuseblk(void) 1890 { 1891 } 1892 #endif 1893 1894 static void fuse_inode_init_once(void *foo) 1895 { 1896 struct inode *inode = foo; 1897 1898 inode_init_once(inode); 1899 } 1900 1901 static int __init fuse_fs_init(void) 1902 { 1903 int err; 1904 1905 fuse_inode_cachep = kmem_cache_create("fuse_inode", 1906 sizeof(struct fuse_inode), 0, 1907 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT, 1908 fuse_inode_init_once); 1909 err = -ENOMEM; 1910 if (!fuse_inode_cachep) 1911 goto out; 1912 1913 err = register_fuseblk(); 1914 if (err) 1915 goto out2; 1916 1917 err = register_filesystem(&fuse_fs_type); 1918 if (err) 1919 goto out3; 1920 1921 return 0; 1922 1923 out3: 1924 unregister_fuseblk(); 1925 out2: 1926 kmem_cache_destroy(fuse_inode_cachep); 1927 out: 1928 return err; 1929 } 1930 1931 static void fuse_fs_cleanup(void) 1932 { 1933 unregister_filesystem(&fuse_fs_type); 1934 unregister_fuseblk(); 1935 1936 /* 1937 * Make sure all delayed rcu free inodes are flushed before we 1938 * destroy cache. 1939 */ 1940 rcu_barrier(); 1941 kmem_cache_destroy(fuse_inode_cachep); 1942 } 1943 1944 static struct kobject *fuse_kobj; 1945 1946 static int fuse_sysfs_init(void) 1947 { 1948 int err; 1949 1950 fuse_kobj = kobject_create_and_add("fuse", fs_kobj); 1951 if (!fuse_kobj) { 1952 err = -ENOMEM; 1953 goto out_err; 1954 } 1955 1956 err = sysfs_create_mount_point(fuse_kobj, "connections"); 1957 if (err) 1958 goto out_fuse_unregister; 1959 1960 return 0; 1961 1962 out_fuse_unregister: 1963 kobject_put(fuse_kobj); 1964 out_err: 1965 return err; 1966 } 1967 1968 static void fuse_sysfs_cleanup(void) 1969 { 1970 sysfs_remove_mount_point(fuse_kobj, "connections"); 1971 kobject_put(fuse_kobj); 1972 } 1973 1974 static int __init fuse_init(void) 1975 { 1976 int res; 1977 1978 pr_info("init (API version %i.%i)\n", 1979 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); 1980 1981 INIT_LIST_HEAD(&fuse_conn_list); 1982 res = fuse_fs_init(); 1983 if (res) 1984 goto err; 1985 1986 res = fuse_dev_init(); 1987 if (res) 1988 goto err_fs_cleanup; 1989 1990 res = fuse_sysfs_init(); 1991 if (res) 1992 goto err_dev_cleanup; 1993 1994 res = fuse_ctl_init(); 1995 if (res) 1996 goto err_sysfs_cleanup; 1997 1998 sanitize_global_limit(&max_user_bgreq); 1999 sanitize_global_limit(&max_user_congthresh); 2000 2001 return 0; 2002 2003 err_sysfs_cleanup: 2004 fuse_sysfs_cleanup(); 2005 err_dev_cleanup: 2006 fuse_dev_cleanup(); 2007 err_fs_cleanup: 2008 fuse_fs_cleanup(); 2009 err: 2010 return res; 2011 } 2012 2013 static void __exit fuse_exit(void) 2014 { 2015 pr_debug("exit\n"); 2016 2017 fuse_ctl_cleanup(); 2018 fuse_sysfs_cleanup(); 2019 fuse_fs_cleanup(); 2020 fuse_dev_cleanup(); 2021 } 2022 2023 module_init(fuse_init); 2024 module_exit(fuse_exit); 2025