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, 3 insertions, 6 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a415465f97a0..eb1e385d8080 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2805,8 +2805,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
         }
         len = ext4_free_group_clusters(sb, gdp) - ac->ac_b_ex.fe_len;
         ext4_free_group_clusters_set(sb, gdp, len);
-        ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh,
-                                   EXT4_BLOCKS_PER_GROUP(sb) / 8);
+        ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh);
         ext4_group_desc_csum_set(sb, ac->ac_b_ex.fe_group, gdp);
 
         ext4_unlock_group(sb, ac->ac_b_ex.fe_group);
@@ -4666,8 +4665,7 @@ do_more:
 
         ret = ext4_free_group_clusters(sb, gdp) + count_clusters;
         ext4_free_group_clusters_set(sb, gdp, ret);
-        ext4_block_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
-                                   EXT4_BLOCKS_PER_GROUP(sb) / 8);
+        ext4_block_bitmap_csum_set(sb, block_group, gdp, bitmap_bh);
         ext4_group_desc_csum_set(sb, block_group, gdp);
         ext4_unlock_group(sb, block_group);
         percpu_counter_add(&sbi->s_freeclusters_counter, count_clusters);
@@ -4811,8 +4809,7 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
         mb_free_blocks(NULL, &e4b, bit, count);
         blk_free_count = blocks_freed + ext4_free_group_clusters(sb, desc);
         ext4_free_group_clusters_set(sb, desc, blk_free_count);
-        ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh,
-                                   EXT4_BLOCKS_PER_GROUP(sb) / 8);
+        ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh);
         ext4_group_desc_csum_set(sb, block_group, desc);
         ext4_unlock_group(sb, block_group);
         percpu_counter_add(&sbi->s_freeclusters_counter,