From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:39066 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932233AbcEEJod (ORCPT ); Thu, 5 May 2016 05:44:33 -0400 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 06BBBAD9C for ; Thu, 5 May 2016 09:44:32 +0000 (UTC) From: David Sterba To: stable@vger.kernel.org Subject: [PATCH 12/17] btrfs: do not write corrupted metadata blocks to disk Date: Thu, 5 May 2016 11:44:15 +0200 Message-Id: <1462441455-3036-1-git-send-email-dsterba@suse.com> In-Reply-To: <20160505094018.GA29353@twin.jikos.cz> References: <20160505094018.GA29353@twin.jikos.cz> Sender: stable-owner@vger.kernel.org List-ID: From: Alex Lyakas csum_dirty_buffer was issuing a warning in case the extent buffer did not look alright, but was still returning success. Let's return error in this case, and also add an additional sanity check on the extent buffer header. The caller up the chain may BUG_ON on this, for example flush_epd_write_bio will, but it is better than to have a silent metadata corruption on disk. Signed-off-by: Alex Lyakas Reviewed-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 87946c69c68f..ae6e3e36fdf0 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -513,9 +513,20 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page) eb = (struct extent_buffer *)page->private; if (page != eb->pages[0]) return 0; + found_start = btrfs_header_bytenr(eb); - if (WARN_ON(found_start != start || !PageUptodate(page))) - return 0; + /* + * Please do not consolidate these warnings into a single if. + * It is useful to know what went wrong. + */ + if (WARN_ON(found_start != start)) + return -EUCLEAN; + if (WARN_ON(!PageUptodate(page))) + return -EUCLEAN; + + ASSERT(memcmp_extent_buffer(eb, fs_info->fsid, + btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0); + return csum_tree_block(fs_info, eb, 0); } -- 2.7.1