ext2: initialize opts.s_mount_opt as zero before using it

commit e5f5b717983bccfa033282e9886811635602510e upstream.

We need to initialize opts.s_mount_opt as zero before using it, else we
may get some unexpected mount options.

Fixes: 088519572ca8 ("ext2: Parse mount options into a dedicated structure")
CC: stable@vger.kernel.org
Signed-off-by: xingaopeng <xingaopeng@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 73bd58f..0c38e31 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -895,6 +895,7 @@
 	if (sb->s_magic != EXT2_SUPER_MAGIC)
 		goto cantfind_ext2;
 
+	opts.s_mount_opt = 0;
 	/* Set defaults before we parse the mount options */
 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 	if (def_mount_opts & EXT2_DEFM_DEBUG)