From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: [PATCH 5/5] ext4: Mark group corrupt on group descriptor checksum error Date: Fri, 19 Jul 2013 16:56:05 -0700 Message-ID: <20130719235605.24017.35311.stgit@blackbox.djwong.org> References: <20130719235532.24017.31896.stgit@blackbox.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: "Theodore Ts'o" , "Darrick J. Wong" Return-path: Received: from userp1040.oracle.com ([156.151.31.81]:36475 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751132Ab3GSX4O (ORCPT ); Fri, 19 Jul 2013 19:56:14 -0400 In-Reply-To: <20130719235532.24017.31896.stgit@blackbox.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: 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 --- fs/ext4/balloc.c | 9 ++++----- fs/ext4/ialloc.c | 10 ++++------ 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index b4c406b..f19e94d 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -184,6 +184,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, 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 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, * 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); diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 08c7fa7..f75be27 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -70,18 +70,16 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb, ext4_group_t block_group, struct ext4_group_desc *gdp) { + struct ext4_group_info *grp; J_ASSERT_BH(bh, buffer_locked(bh)); /* If checksum is bad mark all blocks and inodes use to prevent * allocation, 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_inode_bitmap_csum_set(sb, block_group, gdp, bh, - EXT4_INODES_PER_GROUP(sb) / 8); + 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 0; }