Zhang Yi 019b59aeb2 jbd2: fix a race when checking checkpoint buffer busy ... [ Upstream commit 46f881b5b1 ] Before removing checkpoint buffer from the t_checkpoint_list, we have to check both BH_Dirty and BH_Lock bits together to distinguish buffers have not been or were being written back. But __cp_buffer_busy() checks them separately, it first check lock state and then check dirty, the window between these two checks could be raced by writing back procedure, which locks buffer and clears buffer dirty before I/O completes. So it cannot guarantee checkpointing buffers been written back to disk if some error happens later. Finally, it may clean checkpoint transactions and lead to inconsistent filesystem. jbd2_journal_forget() and __journal_try_to_free_buffer() also have the same problem (journal_unmap_buffer() escape from this issue since it's running under the buffer lock), so fix them through introducing a new helper to try holding the buffer lock and remove really clean buffer. Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490 Cc: stable@vger.kernel.org Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230606135928.434610-6-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-08-30 14:52:28 +02:00
..
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
checkpoint.c	jbd2: fix a race when checking checkpoint buffer busy	2023-08-30 14:52:28 +02:00
commit.c	jbd2: remove t_checkpoint_io_list	2023-08-30 14:52:28 +02:00
journal.c	Bug fixes and regressions for ext4, the most serious of which is a	2023-03-12 08:55:55 -07:00
recovery.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
revoke.c	jbd2: rename jbd_debug() to jbd2_debug()	2022-08-02 23:52:19 -04:00
transaction.c	jbd2: fix a race when checking checkpoint buffer busy	2023-08-30 14:52:28 +02:00