linux-stable/fs/btrfs
Filipe Manana 3d0e7373b2 btrfs: always log symlinks in full mode
commit d0e64a981f upstream.

On Linux, empty symlinks are invalid, and attempting to create one with
the system call symlink(2) results in an -ENOENT error and this is
explicitly documented in the man page.

If we rename a symlink that was created in the current transaction and its
parent directory was logged before, we actually end up logging the symlink
without logging its content, which is stored in an inline extent. That
means that after a power failure we can end up with an empty symlink,
having no content and an i_size of 0 bytes.

It can be easily reproduced like this:

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt

  $ mkdir /mnt/testdir
  $ sync

  # Create a file inside the directory and fsync the directory.
  $ touch /mnt/testdir/foo
  $ xfs_io -c "fsync" /mnt/testdir

  # Create a symlink inside the directory and then rename the symlink.
  $ ln -s /mnt/testdir/foo /mnt/testdir/bar
  $ mv /mnt/testdir/bar /mnt/testdir/baz

  # Now fsync again the directory, this persist the log tree.
  $ xfs_io -c "fsync" /mnt/testdir

  <power failure>

  $ mount /dev/sdc /mnt
  $ stat -c %s /mnt/testdir/baz
  0
  $ readlink /mnt/testdir/baz
  $

Fix this by always logging symlinks in full mode (LOG_INODE_ALL), so that
their content is also logged.

A test case for fstests will follow.

CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-12 12:30:20 +02:00
..
tests btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
acl.c overlayfs update for 5.15 2021-09-02 09:21:27 -07:00
async-thread.c btrfs: fix memory ordering between normal and ordered work functions 2021-11-25 09:48:46 +01:00
async-thread.h
backref.c btrfs: remove BUG_ON(!eie) in find_parent_nodes 2022-01-27 11:04:52 +01:00
backref.h btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
block-group.c btrfs: remove unused variable in btrfs_{start,write}_dirty_block_groups() 2022-04-20 09:34:04 +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_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
compression.c btrfs: remove unused parameter nr_pages in add_ra_bio_pages() 2022-04-20 09:34:04 +02:00
compression.h btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
ctree.c btrfs: make send work with concurrent block group relocation 2022-03-16 14:23:46 +01:00
ctree.h btrfs: skip reserved bytes warning on unmount after log cleanup failure 2022-03-23 09:16:43 +01:00
delalloc-space.c btrfs: free exchange changeset on failures 2021-12-14 10:57:13 +01:00
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: zoned: cache reported zone during mount 2022-02-23 12:03:02 +01:00
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: unify lookup return value when dir entry is missing 2021-10-07 22:06:32 +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: force v2 space cache usage for subpage mount 2022-05-12 12:30:20 +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
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: do not start relocation until in progress drops are done 2022-03-08 19:12:54 +01:00
extent_io.c btrfs: remove no longer used counter when reading data page 2022-04-20 09:34:04 +02:00
extent_io.h btrfs: fix qgroup reserve overflow the qgroup limit 2022-04-13 20:59:23 +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
file-item.c btrfs: make search_csum_tree return 0 if we get -EFBIG 2022-04-08 14:23:58 +02:00
file.c btrfs: fix deadlock due to page faults during direct IO reads and writes 2022-05-01 17:22:33 +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
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: fallback to blocking mode when doing async dio over multiple extents 2022-05-01 17:22:34 +02:00
ioctl.c gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable} 2022-05-01 17:22:28 +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: prevent copying too big compressed lzo segment 2022-03-02 11:48:07 +01:00
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: qgroup: fix deadlock between rescan worker and remove qgroup 2022-03-08 19:12:54 +01:00
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
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: fix unexpected error path when reflinking an inline extent 2022-04-08 14:23:11 +02:00
reflink.h
relocation.c btrfs: make send work with concurrent block group relocation 2022-03-16 14:23:46 +01:00
root-tree.c btrfs: do not start relocation until in progress drops are done 2022-03-08 19:12:54 +01:00
scrub.c btrfs: make 1-bit bit-fields of scrub_page unsigned int 2021-11-25 09:48:37 +01:00
send.c btrfs: make send work with concurrent block group relocation 2022-03-16 14:23:46 +01:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: extend locking to all space_info members accesses 2022-04-08 14:23:02 +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: use latest_dev in btrfs_show_devname 2021-12-22 09:32:37 +01:00
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: make send work with concurrent block group relocation 2022-03-16 14:23:46 +01:00
transaction.h btrfs: do not start relocation until in progress drops are done 2022-03-08 19:12:54 +01:00
tree-checker.c btrfs: tree-checker: check item_size for dev_item 2022-03-02 11:47:48 +01:00
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: always log symlinks in full mode 2022-05-12 12:30:20 +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: mark resumed async balance as writing 2022-04-20 09:34:19 +02:00
volumes.h btrfs: convert latest_bdev type to btrfs_device and rename 2021-12-22 09:32:37 +01:00
xattr.c btrfs: do not BUG_ON() on failure to update inode when setting xattr 2022-05-12 12:30:18 +02:00
xattr.h
zlib.c Revert "btrfs: compression: drop kmap/kunmap from zlib" 2021-10-29 13:03:05 +02:00
zoned.c btrfs: zoned: cache reported zone during mount 2022-02-23 12:03:02 +01:00
zoned.h btrfs: zoned: cache reported zone during mount 2022-02-23 12:03:02 +01:00
zstd.c Revert "btrfs: compression: drop kmap/kunmap from zstd" 2021-10-29 13:02:50 +02:00