ext4: Checksum the block bitmap properly with bigalloc enabled

In mke2fs, we only checksum the whole bitmap block and it is right.
While in the kernel, we use EXT4_BLOCKS_PER_GROUP to indicate the
size of the checksumed bitmap which is wrong when we enable bigalloc.
The right size should be EXT4_CLUSTERS_PER_GROUP and this patch fixes
it.

Also as every caller of ext4_block_bitmap_csum_set and
ext4_block_bitmap_csum_verify pass in EXT4_BLOCKS_PER_GROUP(sb)/8,
we'd better removes this parameter and sets it in the function itself.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Cc: stable@vger.kernel.org

1 files changed, 1 insertions, 3 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index fa36372f3fdf..4facdd29a350 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -762,9 +762,7 @@ got:
                         ext4_free_group_clusters_set(sb, gdp,
                                 ext4_free_clusters_after_init(sb, group, gdp));
                         ext4_block_bitmap_csum_set(sb, group, gdp,
-                                                   block_bitmap_bh,
-                                                   EXT4_BLOCKS_PER_GROUP(sb) /
-                                                   8);
+                                                   block_bitmap_bh);
                         ext4_group_desc_csum_set(sb, group, gdp);
                 }
                 ext4_unlock_group(sb, group);