jbd2: flush filesystem device before updating tail sequence

[ Upstream commit a0851ea9cd555c333795b85ddd908898b937c4e1 ]

When committing transaction in jbd2_journal_commit_transaction(), the
disk caches for the filesystem device should be flushed before updating
the journal tail sequence. However, this step is missed if the journal
is not located on the filesystem device. As a result, the filesystem may
become inconsistent following a power failure or system crash. Fix it by
ensuring that the filesystem device is flushed appropriately.

Fixes: 3339578f0578 ("jbd2: cleanup journal tail after transaction commit")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20241203014407.805916-3-yi.zhang@huaweicloud.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 540a3ccb32875be9d0a08f41d90908264b656dc7..9b2225ab5fe5ad5beb93dcb09bf9cd8bb07d7bb8 100644 (file)
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -810,9 +810,9 @@ start_journal_io:
        /*
         * If the journal is not located on the file system device,
         * then we must flush the file system device before we issue
-        * the commit record
+        * the commit record and update the journal tail sequence.
         */
-       if (commit_transaction->t_need_data_flush &&
+       if ((commit_transaction->t_need_data_flush || update_tail) &&
            (journal->j_fs_dev != journal->j_dev) &&
            (journal->j_flags & JBD2_BARRIER))
                blkdev_issue_flush(journal->j_fs_dev);