[PATCH 4.4 48/97] jbd2: if the journal is aborted then dont allow update of the log tail

From: Greg Kroah-Hartman
Date: Sun Apr 22 2018 - 10:44:01 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Theodore Ts'o <tytso@xxxxxxx>

commit 85e0c4e89c1b864e763c4e3bb15d0b6d501ad5d9 upstream.

This updates the jbd2 superblock unnecessarily, and on an abort we
shouldn't truncate the log.

Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/jbd2/journal.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -914,7 +914,7 @@ out:
}

/*
- * This is a variaon of __jbd2_update_log_tail which checks for validity of
+ * This is a variation of __jbd2_update_log_tail which checks for validity of
* provided log tail and locks j_checkpoint_mutex. So it is safe against races
* with other threads updating log tail.
*/
@@ -1384,6 +1384,9 @@ int jbd2_journal_update_sb_log_tail(jour
journal_superblock_t *sb = journal->j_superblock;
int ret;

+ if (is_journal_aborted(journal))
+ return -EIO;
+
BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n",
tail_block, tail_tid);