ext4: mark group corrupt on group descriptor checksum
If the group descriptor fails validation, mark the whole blockgroup
corrupt so that the inode/block allocators skip this group. The
previous approach takes the risk of writing to a damaged group
descriptor; hopefully it was never the case that the [ib]bitmap fields
pointed to another valid block and got dirtied, since the memset would
fill the page with 1s.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index d9b66c4..dc5d572 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -184,6 +184,7 @@
struct ext4_sb_info *sbi = EXT4_SB(sb);
ext4_fsblk_t start, tmp;
int flex_bg = 0;
+ struct ext4_group_info *grp;
J_ASSERT_BH(bh, buffer_locked(bh));
@@ -191,11 +192,9 @@
* essentially implementing a per-group read-only flag. */
if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
ext4_error(sb, "Checksum bad for group %u", block_group);
- ext4_free_group_clusters_set(sb, gdp, 0);
- ext4_free_inodes_set(sb, gdp, 0);
- ext4_itable_unused_set(sb, gdp, 0);
- memset(bh->b_data, 0xff, sb->s_blocksize);
- ext4_block_bitmap_csum_set(sb, block_group, gdp, bh);
+ grp = ext4_get_group_info(sb, block_group);
+ set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
+ set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
return;
}
memset(bh->b_data, 0, sb->s_blocksize);