From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id C2E347F85 for ; Sun, 29 Sep 2013 22:15:53 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay1.corp.sgi.com (Postfix) with ESMTP id 8E0068F8039 for ; Sun, 29 Sep 2013 20:15:53 -0700 (PDT) Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by cuda.sgi.com with ESMTP id vetK8lvTxNnYSivW for ; Sun, 29 Sep 2013 20:15:52 -0700 (PDT) Received: from disappointment.disaster.area ([192.168.1.110] helo=disappointment) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1VQTxZ-0006Ok-TJ for xfs@oss.sgi.com; Mon, 30 Sep 2013 13:15:45 +1000 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1VQTxZ-0002FK-SI for xfs@oss.sgi.com; Mon, 30 Sep 2013 13:15:45 +1000 From: Dave Chinner Subject: [PATCH 04/32] xfs: check magic numbers in dir3 leaf verifier first Date: Mon, 30 Sep 2013 13:15:16 +1000 Message-Id: <1380510944-8571-5-git-send-email-david@fromorbit.com> In-Reply-To: <1380510944-8571-1-git-send-email-david@fromorbit.com> References: <1380510944-8571-1-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com From: Dave Chinner Calling xfs_dir3_leaf_hdr_from_disk() in a verifier before validating the magic numbers in the buffer results in ASSERT failures due to mismatching magic numbers when a corruption occurs. Seeing as the verifier is supposed to catch the corruption and pass it back to the caller, having the verifier assert fail on error defeats the purpose of detecting the errors in the first place. Check the magic numbers direct from the buffer before decoding the header. Signed-off-by: Dave Chinner --- libxfs/xfs_dir2_leaf.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/libxfs/xfs_dir2_leaf.c b/libxfs/xfs_dir2_leaf.c index 7ec2f19..c035c4d 100644 --- a/libxfs/xfs_dir2_leaf.c +++ b/libxfs/xfs_dir2_leaf.c @@ -161,6 +161,11 @@ xfs_dir3_leaf_check_int( return true; } +/* + * We verify the magic numbers before decoding the leaf header so that on debug + * kernels we don't get assertion failures in xfs_dir3_leaf_hdr_from_disk() due + * to incorrect magic numbers. + */ static bool xfs_dir3_leaf_verify( struct xfs_buf *bp, @@ -172,24 +177,25 @@ xfs_dir3_leaf_verify( ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC); - xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf); if (xfs_sb_version_hascrc(&mp->m_sb)) { struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr; + __uint16_t magic3; - if ((magic == XFS_DIR2_LEAF1_MAGIC && - leafhdr.magic != XFS_DIR3_LEAF1_MAGIC) || - (magic == XFS_DIR2_LEAFN_MAGIC && - leafhdr.magic != XFS_DIR3_LEAFN_MAGIC)) - return false; + magic3 = (magic == XFS_DIR2_LEAF1_MAGIC) ? XFS_DIR3_LEAF1_MAGIC + : XFS_DIR3_LEAFN_MAGIC; + if (leaf3->info.hdr.magic != cpu_to_be16(magic3)) + return false; if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_uuid)) return false; if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn) return false; } else { - if (leafhdr.magic != magic) + if (leaf->hdr.info.magic != cpu_to_be16(magic)) return false; } + + xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf); return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf); } -- 1.8.3.2 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs