add-missing-unlock-to-ext4-check-descriptors

   1 ext4: add missing unlock in ext4_check_descriptors() on error path
   2
   3 From: Li Zefan <lizf@cn.fujitsu.com>
   4
   5 If there group descriptors are corrupted we need unlock the block
   6 group lock before returning from the function; else we will oops when
   7 freeing a spinlock which is still being held.
   8
   9 Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
  10 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
  11 ---
  12  fs/ext4/super.c |    4 +++-
  13  1 files changed, 3 insertions(+), 1 deletions(-)
  14
  15 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
  16 index 566344b..24e7df6 100644
  17 --- a/fs/ext4/super.c
  18 +++ b/fs/ext4/super.c
  19 @@ -1623,8 +1623,10 @@ static int ext4_check_descriptors(struct super_block *sb)
  20                                "Checksum for group %lu failed (%u!=%u)\n",
  21                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
  22                                gdp)), le16_to_cpu(gdp->bg_checksum));
  23 -                       if (!(sb->s_flags & MS_RDONLY))
  24 +                       if (!(sb->s_flags & MS_RDONLY)) {
  25 +                               spin_unlock(sb_bgl_lock(sbi, i));
  26                                 return 0;
  27 +                       }
  28                 }
  29                 spin_unlock(sb_bgl_lock(sbi, i));
  30                 if (!flexbg_flag)