WSL2-Linux-Kernel/fs/ubifs
Richard Weinberger e58725d51f ubifs: Handle re-linking of inodes correctly while recovery
UBIFS's recovery code strictly assumes that a deleted inode will never
come back, therefore it removes all data which belongs to that inode
as soon it faces an inode with link count 0 in the replay list.
Before O_TMPFILE this assumption was perfectly fine. With O_TMPFILE
it can lead to data loss upon a power-cut.

Consider a journal with entries like:
0: inode X (nlink = 0) /* O_TMPFILE was created */
1: data for inode X /* Someone writes to the temp file */
2: inode X (nlink = 0) /* inode was changed, xattr, chmod, … */
3: inode X (nlink = 1) /* inode was re-linked via linkat() */

Upon replay of entry #2 UBIFS will drop all data that belongs to inode X,
this will lead to an empty file after mounting.

As solution for this problem, scan the replay list for a re-link entry
before dropping data.

Fixes: 474b93704f ("ubifs: Implement O_TMPFILE")
Cc: stable@vger.kernel.org
Cc: Russell Senior <russell@personaltelco.net>
Cc: Rafał Miłecki <zajec5@gmail.com>
Reported-by: Russell Senior <russell@personaltelco.net>
Reported-by: Rafał Miłecki <zajec5@gmail.com>
Tested-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-12-13 22:18:24 +01:00
..
Kconfig ubifs: auth: Add CONFIG_KEYS dependency 2018-12-13 22:09:07 +01:00
Makefile ubifs: Add helper functions for authentication support 2018-10-23 13:48:33 +02:00
auth.c ubifs: Add helper functions for authentication support 2018-10-23 13:48:33 +02:00
budget.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
commit.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
compress.c UBIFS: extend debug/message capabilities 2015-03-25 11:08:41 +02:00
crypto.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
debug.c ubifs: Format changes for authentication support 2018-10-23 13:48:29 +02:00
debug.h ubifs: Rework ubifs_assert() 2018-08-15 00:25:21 +02:00
dir.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
file.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
find.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
gc.c ubifs: Add auth nodes to garbage collector journal head 2018-10-23 13:48:40 +02:00
io.c ubifs: Create functions to embed a HMAC in a node 2018-10-23 13:48:37 +02:00
ioctl.c fs, fscrypt: add an S_ENCRYPTED inode flag 2017-10-18 19:52:36 -04:00
journal.c ubifs: Add authentication nodes to journal 2018-10-23 13:48:39 +02:00
key.h ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
log.c ubifs: Add authentication nodes to journal 2018-10-23 13:48:39 +02:00
lprops.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
lpt.c ubifs: Fix memory leak on error condition 2018-12-13 22:09:13 +01:00
lpt_commit.c ubifs: authentication: Authenticate LPT 2018-10-23 13:48:47 +02:00
master.c ubfis: authentication: Authenticate master node 2018-10-23 13:48:52 +02:00
misc.c ubifs: Allow setting assert action as mount parameter 2018-08-15 00:25:21 +02:00
misc.h ubifs: authentication: Add hashes to index nodes 2018-10-23 13:48:39 +02:00
orphan.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
recovery.c ubifs: Do not update inode size in-place in authenticated mode 2018-10-23 13:48:57 +02:00
replay.c ubifs: Handle re-linking of inodes correctly while recovery 2018-12-13 22:18:24 +01:00
sb.c ubifs: Fix default compression selection in ubifs 2018-12-13 22:09:19 +01:00
scan.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
shrinker.c ubifs: Pass struct ubifs_info to ubifs_assert() 2018-08-15 00:25:21 +02:00
super.c ubifs: Enable authentication support 2018-10-23 13:49:01 +02:00
tnc.c ubifs: authentication: Add hashes to index nodes 2018-10-23 13:48:39 +02:00
tnc_commit.c ubifs: authentication: Add hashes to index nodes 2018-10-23 13:48:39 +02:00
tnc_misc.c ubifs: authentication: Add hashes to index nodes 2018-10-23 13:48:39 +02:00
ubifs-media.h ubifs: Format changes for authentication support 2018-10-23 13:48:29 +02:00
ubifs.h ubifs: Do not update inode size in-place in authenticated mode 2018-10-23 13:48:57 +02:00
xattr.c Revert "ubifs: xattr: Don't operate on deleted inodes" 2018-09-20 21:37:41 +02:00