From: Theodore Ts'o Subject: [PATCH FOR-STABLE-2.6.27 24/24] ext4: Initialize the new group descriptor when resizing the filesystem Date: Tue, 17 Feb 2009 10:58:44 -0500 Message-ID: <1234886324-15105-25-git-send-email-tytso@mit.edu> References: <1234886324-15105-1-git-send-email-tytso@mit.edu> <1234886324-15105-2-git-send-email-tytso@mit.edu> <1234886324-15105-3-git-send-email-tytso@mit.edu> <1234886324-15105-4-git-send-email-tytso@mit.edu> <1234886324-15105-5-git-send-email-tytso@mit.edu> <1234886324-15105-6-git-send-email-tytso@mit.edu> <1234886324-15105-7-git-send-email-tytso@mit.edu> <1234886324-15105-8-git-send-email-tytso@mit.edu> <1234886324-15105-9-git-send-email-tytso@mit.edu> <1234886324-15105-10-git-send-email-tytso@mit.edu> <1234886324-15105-11-git-send-email-tytso@mit.edu> <1234886324-15105-12-git-send-email-tytso@mit.edu> <1234886324-15105-13-git-send-email-tytso@mit.edu> <1234886324-15105-14-git-send-email-tytso@mit.edu> <1234886324-15105-15-git-send-email-tytso@mit.edu> <1234886324-15105-16-git-send-email-tytso@mit.edu> <1234886324-15105-17-git-send-email-tytso@mit.edu> <1234886324-15105-18-git-send-email-tytso@mit.edu> <1234886324-15105-19-git-send-email-tytso@mit.edu> <1234886324-15105-20-git-send-email-tytso@mit.edu> <1234886324-15105-21-git-send-email-tytso@mit.edu> <1234886324-15105-22-git-send-email-tytso@mit.edu> <1234886324-15105-23-git-send-email-tytso@mit.edu> <1234886324-15105-24-git-send-email-tytso@mit.edu> Cc: linux-ext4@vger.kernel.org, Theodore Ts'o To: stable@kernel.org Return-path: Received: from thunk.org ([69.25.196.29]:40530 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751396AbZBQQbj (ORCPT ); Tue, 17 Feb 2009 11:31:39 -0500 In-Reply-To: <1234886324-15105-24-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: Make sure all of the fields of the group descriptor are properly initialized. Previously, we allowed bg_flags field to be contain random garbage, which could trigger non-deterministic behavior, including a kernel OOPS. http://bugzilla.kernel.org/show_bug.cgi?id=12433 Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org (cherry picked from commit fdff73f094e7220602cc3f8959c7230517976412) --- fs/ext4/resize.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index cfb8e36..0070431 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -860,11 +860,13 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) gdp = (struct ext4_group_desc *)((char *)primary->b_data + gdb_off * EXT4_DESC_SIZE(sb)); + memset(gdp, 0, EXT4_DESC_SIZE(sb)); ext4_block_bitmap_set(sb, gdp, input->block_bitmap); /* LV FIXME */ ext4_inode_bitmap_set(sb, gdp, input->inode_bitmap); /* LV FIXME */ ext4_inode_table_set(sb, gdp, input->inode_table); /* LV FIXME */ gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count); gdp->bg_free_inodes_count = cpu_to_le16(EXT4_INODES_PER_GROUP(sb)); + gdp->bg_flags = cpu_to_le16(EXT4_BG_INODE_ZEROED); gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp); /* -- 1.5.6.3