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

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>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 64e1c21eb5d2..8175318abd84 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1623,8 +1623,10 @@ 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)