From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:53617 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932226AbcEKMsJ (ORCPT ); Wed, 11 May 2016 08:48:09 -0400 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id E4388AC62 for ; Wed, 11 May 2016 12:48:07 +0000 (UTC) From: David Sterba To: stable@vger.kernel.org Subject: [PATCH 12/17] btrfs: do not write corrupted metadata blocks to disk Date: Wed, 11 May 2016 14:47:46 +0200 Message-Id: <1462970866-17190-1-git-send-email-dsterba@suse.com> In-Reply-To: <20160511124536.GB29353@suse.cz> References: <20160511124536.GB29353@suse.cz> Sender: stable-owner@vger.kernel.org List-ID: From: Alex Lyakas commit 0f805531daa2ebfb5706422dc2ead1cff9e53e65 upstream. 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