From: Eric Sandeen Subject: [PATCH] fix inode_table test in ext234_check_descriptors Date: Mon, 23 Jul 2007 12:16:04 -0500 Message-ID: <46A4E254.3010606@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Linux Kernel Mailing List To: ext4 development Return-path: Received: from mx1.redhat.com ([66.187.233.31]:42258 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758746AbXGWRWT (ORCPT ); Mon, 23 Jul 2007 13:22:19 -0400 Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org ext[234]_check_descriptors sanity checks block group descriptor geometry at mount time, testing whether the block bitmap, inode bitmap, and inode table reside wholly within the blockgroup. However, the inode table test is off by one so that if the last block in the inode table resides on the last block of the block group, the test incorrectly fails. This is because it tests the last block as (start + length) rather than (start + length - 1). This can be seen by trying to mount a filesystem made such as: mkfs.ext2 -F -b 1024 -m 0 -g 256 -N 3744 fsfile 1024 which yields: EXT2-fs error (device loop0): ext2_check_descriptors: Inode table for group 0 not in group (block 101)! EXT2-fs: group descriptors corrupted! There is a similar bug in e2fsprogs, patch already sent for that. (I wonder if inside(), outside(), and/or in_range() should someday be used in this and other tests throughout the ext filesystems...) Signed-off-by: Eric Sandeen Index: linux-2.6.22-rc4/fs/ext2/super.c =================================================================== --- linux-2.6.22-rc4.orig/fs/ext2/super.c +++ linux-2.6.22-rc4/fs/ext2/super.c @@ -579,7 +579,7 @@ static int ext2_check_descriptors (struc return 0; } if (le32_to_cpu(gdp->bg_inode_table) < first_block || - le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > + le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > last_block) { ext2_error (sb, "ext2_check_descriptors", Index: linux-2.6.22-rc4/fs/ext3/super.c =================================================================== --- linux-2.6.22-rc4.orig/fs/ext3/super.c +++ linux-2.6.22-rc4/fs/ext3/super.c @@ -1211,7 +1211,7 @@ static int ext3_check_descriptors (struc return 0; } if (le32_to_cpu(gdp->bg_inode_table) < first_block || - le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > + le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > last_block) { ext3_error (sb, "ext3_check_descriptors", Index: linux-2.6.22-rc4/fs/ext4/super.c =================================================================== --- linux-2.6.22-rc4.orig/fs/ext4/super.c +++ linux-2.6.22-rc4/fs/ext4/super.c @@ -1269,7 +1269,7 @@ static int ext4_check_descriptors (struc } inode_table = ext4_inode_table(sb, gdp); if (inode_table < first_block || - inode_table + sbi->s_itb_per_group > last_block) + inode_table + sbi->s_itb_per_group - 1 > last_block) { ext4_error (sb, "ext4_check_descriptors", "Inode table for group %d"