[PATCH AUTOSEL 4.9 21/87] jbd2: fix invalid descriptor block checksum

From: Sasha Levin
Date: Wed Mar 27 2019 - 14:44:31 EST


From: luojiajun <luojiajun3@xxxxxxxxxx>

[ Upstream commit 6e876c3dd205d30b0db6850e97a03d75457df007 ]

In jbd2_journal_commit_transaction(), if we are in abort mode,
we may flush the buffer without setting descriptor block checksum
by goto start_journal_io. Then fs is mounted,
jbd2_descriptor_block_csum_verify() failed.

[ 271.379811] EXT4-fs (vdd): shut down requested (2)
[ 271.381827] Aborting journal on device vdd-8.
[ 271.597136] JBD2: Invalid checksum recovering block 22199 in log
[ 271.598023] JBD2: recovery failed
[ 271.598484] EXT4-fs (vdd): error loading journal

Fix this problem by keep setting descriptor block checksum if the
descriptor buffer is not NULL.

This checksum problem can be reproduced by xfstests generic/388.

Signed-off-by: luojiajun <luojiajun3@xxxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/jbd2/commit.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 31f8ca046639..10ec27676191 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -700,9 +700,11 @@ void jbd2_journal_commit_transaction(journal_t *journal)
the last tag we set up. */

tag->t_flags |= cpu_to_be16(JBD2_FLAG_LAST_TAG);
-
- jbd2_descriptor_block_csum_set(journal, descriptor);
start_journal_io:
+ if (descriptor)
+ jbd2_descriptor_block_csum_set(journal,
+ descriptor);
+
for (i = 0; i < bufs; i++) {
struct buffer_head *bh = wbuf[i];
/*
--
2.19.1