ext4: add missing unlock in ext4_check_descriptors() on error path

(cherry picked from commit 7ee1ec4ca30c6df8e989615cdaacb75f2af4fa6b)

If there group descriptors are corrupted we need unlock the block
group lock before returning from the function; else we will oops when
freeing a spinlock which is still being held.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 062b7c5dc68fd5930fdd0463caf888ac1221095f..f98f9bbf98c1ce9308fe47574dbdb05672da2fcd 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1626,8 +1626,10 @@ static int ext4_check_descriptors(struct super_block *sb)
                               "Checksum for group %lu failed (%u!=%u)\n",
                               i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
                               gdp)), le16_to_cpu(gdp->bg_checksum));
-                       if (!(sb->s_flags & MS_RDONLY))
+                       if (!(sb->s_flags & MS_RDONLY)) {
+                               spin_unlock(sb_bgl_lock(sbi, i));
                                return 0;
+                       }
                }
                spin_unlock(sb_bgl_lock(sbi, i));
                if (!flexbg_flag)