linux/fs/btrfs
Qu Wenruo 19ea40dddf btrfs: unlock newly allocated extent buffer after error
[BUG]
There is a bug report that injected ENOMEM error could leave a tree
block locked while we return to user-space:

  BTRFS info (device loop0): enabling ssd optimizations
  FAULT_INJECTION: forcing a failure.
  name failslab, interval 1, probability 0, space 0, times 0
  CPU: 0 PID: 7579 Comm: syz-executor Not tainted 5.15.0-rc1 #16
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
  rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
  Call Trace:
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:106
   fail_dump lib/fault-inject.c:52 [inline]
   should_fail+0x13c/0x160 lib/fault-inject.c:146
   should_failslab+0x5/0x10 mm/slab_common.c:1328
   slab_pre_alloc_hook.constprop.99+0x4e/0xc0 mm/slab.h:494
   slab_alloc_node mm/slub.c:3120 [inline]
   slab_alloc mm/slub.c:3214 [inline]
   kmem_cache_alloc+0x44/0x280 mm/slub.c:3219
   btrfs_alloc_delayed_extent_op fs/btrfs/delayed-ref.h:299 [inline]
   btrfs_alloc_tree_block+0x38c/0x670 fs/btrfs/extent-tree.c:4833
   __btrfs_cow_block+0x16f/0x7d0 fs/btrfs/ctree.c:415
   btrfs_cow_block+0x12a/0x300 fs/btrfs/ctree.c:570
   btrfs_search_slot+0x6b0/0xee0 fs/btrfs/ctree.c:1768
   btrfs_insert_empty_items+0x80/0xf0 fs/btrfs/ctree.c:3905
   btrfs_new_inode+0x311/0xa60 fs/btrfs/inode.c:6530
   btrfs_create+0x12b/0x270 fs/btrfs/inode.c:6783
   lookup_open+0x660/0x780 fs/namei.c:3282
   open_last_lookups fs/namei.c:3352 [inline]
   path_openat+0x465/0xe20 fs/namei.c:3557
   do_filp_open+0xe3/0x170 fs/namei.c:3588
   do_sys_openat2+0x357/0x4a0 fs/open.c:1200
   do_sys_open+0x87/0xd0 fs/open.c:1216
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  RIP: 0033:0x46ae99
  Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48
  89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d
  01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007f46711b9c48 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
  RAX: ffffffffffffffda RBX: 000000000078c0a0 RCX: 000000000046ae99
  RDX: 0000000000000000 RSI: 00000000000000a1 RDI: 0000000020005800
  RBP: 00007f46711b9c80 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000017
  R13: 0000000000000000 R14: 000000000078c0a0 R15: 00007ffc129da6e0

  ================================================
  WARNING: lock held when returning to user space!
  5.15.0-rc1 #16 Not tainted
  ------------------------------------------------
  syz-executor/7579 is leaving the kernel with locks still held!
  1 lock held by syz-executor/7579:
   #0: ffff888104b73da8 (btrfs-tree-01/1){+.+.}-{3:3}, at:
  __btrfs_tree_lock+0x2e/0x1a0 fs/btrfs/locking.c:112

[CAUSE]
In btrfs_alloc_tree_block(), after btrfs_init_new_buffer(), the new
extent buffer @buf is locked, but if later operations like adding
delayed tree ref fail, we just free @buf without unlocking it,
resulting above warning.

[FIX]
Unlock @buf in out_free_buf: label.

Reported-by: Hao Sun <sunhao.th@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CACkBjsZ9O6Zr0KK1yGn=1rQi6Crh1yeCRdTSBxx9R99L4xdn-Q@mail.gmail.com/
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-07 22:04:20 +02:00
..
tests btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
acl.c btrfs: handle ACLs on idmapped mounts 2021-08-23 13:19:15 +02:00
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
backref.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
backref.h btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
block-group.c btrfs: zoned: suppress reclaim error message on EAGAIN 2021-08-23 13:19:11 +02:00
block-group.h btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
btrfs_inode.h btrfs: initial fsverity support 2021-08-23 13:19:09 +02:00
check-integrity.c btrfs: check-integrity: drop kmap/kunmap for block pages 2021-08-23 13:19:00 +02:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
compression.h btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
ctree.c btrfs: introduce btrfs_search_backwards function 2021-08-23 13:19:09 +02:00
ctree.h btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctls 2021-08-23 13:19:14 +02:00
delalloc-space.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: add ro compat flags to inodes 2021-08-23 13:19:09 +02:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: fix lock inversion problem when doing qgroup extent tracing 2021-07-22 15:50:07 +02:00
delayed-ref.h btrfs: only let one thread pre-flush delayed refs in commit 2021-02-08 22:58:56 +01:00
dev-replace.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: introduce btrfs_lookup_match_dir 2021-08-23 13:19:02 +02:00
discard.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: fix upper limit for max_inline for page size 64K 2021-09-07 14:28:46 +02:00
disk-io.h btrfs: split alloc_log_tree() 2021-02-09 02:46:07 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
extent_io.c btrfs: zoned: fix ordered extent boundary calculation 2021-08-23 13:19:16 +02:00
extent_io.h btrfs: fix argument type of btrfs_bio_clone_partial() 2021-08-23 13:19:08 +02:00
extent_map.c btrfs: fix parameter description of btrfs_add_extent_mapping 2021-02-08 22:58:53 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: unlock newly allocated extent buffer after error 2021-10-07 22:04:20 +02:00
file-item.c btrfs: replace BUG_ON() in btrfs_csum_one_bio() with proper error handling 2021-09-17 19:29:38 +02:00
file.c btrfs: initial fsverity support 2021-08-23 13:19:09 +02:00
free-space-cache.c btrfs: zoned: fix block group alloc_offset calculation 2021-08-23 13:19:11 +02:00
free-space-cache.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctls 2021-08-23 13:19:14 +02:00
ioctl.c btrfs: delay blkdev_put until after the device remove 2021-09-07 14:29:59 +02:00
Kconfig btrfs: disable build on platforms having page size 256K 2021-06-22 14:11:57 +02:00
locking.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c btrfs: rework lzo_decompress_bio() to make it subpage compatible 2021-08-23 13:19:04 +02:00
Makefile btrfs: initial fsverity support 2021-08-23 13:19:09 +02:00
misc.h btrfs: use correct header for div_u64 in misc.h 2021-09-07 14:29:50 +02:00
ordered-data.c btrfs: zoned: fix double counting of split ordered extent 2021-09-07 14:30:41 +02:00
ordered-data.h btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pending 2021-08-23 13:19:02 +02:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: props: change how empty value is interpreted 2021-06-22 14:11:58 +02:00
props.h
qgroup.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
qgroup.h btrfs: fix lock inversion problem when doing qgroup extent tracing 2021-07-22 15:50:07 +02:00
raid56.c btrfs: constify and cleanup variables in comparators 2021-08-23 13:19:03 +02:00
raid56.h
rcu-string.h btrfs: rcu-string: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
reada.c btrfs: subpage: make readahead work properly 2021-03-16 11:06:21 +01:00
ref-verify.c btrfs: stop doing GFP_KERNEL memory allocations in the ref verify tool 2021-08-23 13:19:00 +02:00
ref-verify.h
reflink.c btrfs: reflink: make copy_inline_to_page() to be subpage compatible 2021-06-21 15:19:10 +02:00
reflink.h Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
relocation.c btrfs: subpage: fix relocation potentially overwriting last page data 2021-08-23 13:19:06 +02:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
send.c btrfs: allocate backref_ctx on stack in find_extent_clone 2021-08-23 13:19:10 +02:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: prevent __btrfs_dump_space_info() to underflow its free space 2021-09-17 19:29:54 +02:00
space-info.h btrfs: rip out btrfs_space_info::total_bytes_pinned 2021-06-22 14:55:25 +02:00
struct-funcs.c btrfs: add special case to setget helpers for 64k pages 2021-08-23 13:18:58 +02:00
subpage.c btrfs: subpage: fix a potential use-after-free in writeback helper 2021-08-23 13:19:05 +02:00
subpage.h btrfs: subpage: fix writeback which does not have ordered extent 2021-08-23 13:19:04 +02:00
super.c btrfs: allow idmapped mount 2021-08-23 13:19:15 +02:00
sysfs.c btrfs: sysfs: document structures and their associated files 2021-08-23 13:19:12 +02:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
transaction.h btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
tree-checker.c btrfs: add ro compat flags to inodes 2021-08-23 13:19:09 +02:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: tree-log: check btrfs_lookup_data_extent return value 2021-08-23 13:19:15 +02:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +02:00
tree-mod-log.c btrfs: fix race when picking most recent mod log operation for an old root 2021-04-20 19:27:17 +02:00
tree-mod-log.h btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
verity.c btrfs: fix transaction handle leak after verity rollback failure 2021-09-17 19:29:41 +02:00
volumes.c btrfs: fix mount failure due to past and transient device flush error 2021-09-17 19:29:45 +02:00
volumes.h btrfs: delay blkdev_put until after the device remove 2021-09-07 14:29:59 +02:00
xattr.c for-5.12-rc1-tag 2021-03-05 12:21:14 -08:00
xattr.h
zlib.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
zoned.c btrfs: use btrfs_next_leaf instead of btrfs_next_item when slots > nritems 2021-08-23 13:19:01 +02:00
zoned.h btrfs: zoned: remove max_zone_append_size logic 2021-08-23 13:18:58 +02:00
zstd.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00