add-missing-brelse-in-add_new_gdb_meta_bg

   1 ext4: add missing brelse() in add_new_gdb_meta_bg()
   2
   3 From: Lukas Czerner <lczerner@redhat.com>
   4
   5 Currently in add_new_gdb_meta_bg() there is a missing brelse of gdb_bh
   6 in case ext4_journal_get_write_access() fails.
   7 Additionally kvfree() is missing in the same error path. Fix it by
   8 moving the ext4_journal_get_write_access() before the ext4 sb update as
   9 Ted suggested and release n_group_desc and gdb_bh in case it fails.
  10
  11 Fixes: 61a9c11e5e7a ("ext4: add missing brelse() add_new_gdb_meta_bg()'s error path")
  12 Signed-off-by: Lukas Czerner <lczerner@redhat.com>
  13 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  14 ---
  15 v2: Move ext4_journal_get_write_access() before we update ext4 sb
  16
  17  fs/ext4/resize.c | 11 +++++++++--
  18  1 file changed, 9 insertions(+), 2 deletions(-)
  19
  20 diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
  21 index 48421de803b7..5f89c19043a2 100644
  22 --- a/fs/ext4/resize.c
  23 +++ b/fs/ext4/resize.c
  24 @@ -932,11 +932,18 @@ static int add_new_gdb_meta_bg(struct super_block *sb,
  25         memcpy(n_group_desc, o_group_desc,
  26                EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
  27         n_group_desc[gdb_num] = gdb_bh;
  28 +
  29 +       BUFFER_TRACE(gdb_bh, "get_write_access");
  30 +       err = ext4_journal_get_write_access(handle, gdb_bh);
  31 +       if (err) {
  32 +               kvfree(n_group_desc);
  33 +               brelse(gdb_bh);
  34 +               return err;
  35 +       }
  36 +
  37         EXT4_SB(sb)->s_group_desc = n_group_desc;
  38         EXT4_SB(sb)->s_gdb_count++;
  39         kvfree(o_group_desc);
  40 -       BUFFER_TRACE(gdb_bh, "get_write_access");
  41 -       err = ext4_journal_get_write_access(handle, gdb_bh);
  42         return err;
  43  }
  44
  45 --
  46 2.20.1
  47
  48