ext4: fix possible inode leak in the retry loop of ext4_resize_fs()

BugLink: https://bugs.launchpad.net/bugs/1810947

commit db6aee62 upstream.

Fixes: 1c6bd717 ("ext4: convert file system to meta_bg if needed ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 3.7
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

fs/ext4/resize.c

@@ -2026,6 +2026,10 @@ int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count)
 		n_blocks_count_retry = 0;
 		free_flex_gd(flex_gd);
 		flex_gd = NULL;
+		if (resize_inode) {
+			iput(resize_inode);
+			resize_inode = NULL;
+		}
 		goto retry;
 	}