From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maarten ter Huurne , "Theodore Tso" , Jan Kara Subject: [ 08/72] ext4: fix corruption when online resizing a fs with 1K block size Date: Thu, 18 Jul 2013 22:25:25 -0700 Message-Id: <20130719052600.429858412@linuxfoundation.org> In-Reply-To: <20130719052559.852627424@linuxfoundation.org> References: <20130719052559.852627424@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maarten ter Huurne commit 6ca792edc13c409e8d4eb9001e048264c6a2eb64 upstream. Subtracting the number of the first data block places the superblock backups one block too early, corrupting the file system. When the block size is larger than 1K, the first data block is 0, so the subtraction has no effect and no corruption occurs. Signed-off-by: Maarten ter Huurne Signed-off-by: "Theodore Ts'o" Reviewed-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/ext4/resize.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1656,12 +1656,10 @@ errout: err = err2; if (!err) { - ext4_fsblk_t first_block; - first_block = ext4_group_first_block_no(sb, 0); if (test_opt(sb, DEBUG)) printk(KERN_DEBUG "EXT4-fs: extended group to %llu " "blocks\n", ext4_blocks_count(es)); - update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr - first_block, + update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es, sizeof(struct ext4_super_block), 0); } return err;