commit 85e0c4e8 upstream.

This updates the jbd2 superblock unnecessarily, and on an abort we
shouldn't truncate the log.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>