ext2: check err when partial != NULL

commit e705f4b8aa27a59f8933e8f384e9752f052c469c upstream.

Check err when partial == NULL is meaningless because
partial == NULL means getting branch successfully without
error.

CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191105045100.7104-1-cgxu519@mykernel.net
Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 85449a6..fe66494 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -697,10 +697,13 @@
 		if (!partial) {
 			count++;
 			mutex_unlock(&ei->truncate_mutex);
-			if (err)
-				goto cleanup;
 			goto got_it;
 		}
+
+		if (err) {
+			mutex_unlock(&ei->truncate_mutex);
+			goto cleanup;
+		}
 	}
 
 	/*