jbd2: free bh when descriptor block checksum fails

commit 064d8389 upstream.

Free the buffer head if the journal descriptor block fails checksum
verification.

This is the jbd2 port of the e2fsprogs patch "e2fsck: free bh on csum
verify error in do_one_pass".
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

fs/jbd2/recovery.c

@@ -525,6 +525,7 @@ static int do_one_pass(journal_t *journal,
 			    !jbd2_descr_block_csum_verify(journal,
 							  bh->b_data)) {
 				err = -EIO;
+				brelse(bh);
 				goto failed;
 			}