ext4: calculate and verify block bitmap checksum

Compute and verify the checksum of the block bitmap; this checksum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index 7810cac241e1..dc597e066308 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -1107,6 +1107,13 @@ static int ext4_set_bitmap_checksums(struct super_block *sb,
                                    EXT4_INODES_PER_GROUP(sb) / 8);
         brelse(bh);
 
+        bh = ext4_get_bitmap(sb, group_data->block_bitmap);
+        if (!bh)
+                return -EIO;
+        ext4_block_bitmap_csum_set(sb, group, gdp, bh,
+                                   EXT4_BLOCKS_PER_GROUP(sb) / 8);
+        brelse(bh);
+
         return 0;
 }