From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 6AF0F7F51 for ; Thu, 15 Aug 2013 17:41:59 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 0635FAC003 for ; Thu, 15 Aug 2013 15:41:55 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id HsmKi1mWC7IQi8If for ; Thu, 15 Aug 2013 15:41:52 -0700 (PDT) Message-ID: <520D592D.4040600@redhat.com> Date: Thu, 15 Aug 2013 17:41:49 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: [PATCH, RFC] xfs: be more forgiving of a v4 secondary sb w/ junk in v5 fields References: <520D1BA3.1050500@redhat.com> <20130815210018.GR6023@dastard> <520D44E7.1000905@sandeen.net> In-Reply-To: <520D44E7.1000905@sandeen.net> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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: Eric Sandeen Cc: "'linux-xfs@oss.sgi.com'" Today, if xfs_sb_read_verify encounters a v4 superblock with junk past v4 fields which includes data in sb_crc, it will be treated as a failing checksum and significant corruption. There are known prior bugs which leave junk at the end of the superblock; we don't need to actually fail the verification in this case if other checks pan out ok. So if this is a secondary superblock, and the primary superblock is not V5, don't treat this as a serious checksum failure. We should probably check the garbage condition as we do in xfs_repair, and possibly warn about it or self-heal, but that's a different scope of work. Signed-off-by: Eric Sandeen --- diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 2b0ba35..5ce25ae 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -769,8 +769,12 @@ xfs_sb_read_verify( if (!xfs_verify_cksum(bp->b_addr, be16_to_cpu(dsb->sb_sectsize), offsetof(struct xfs_sb, sb_crc))) { - error = EFSCORRUPTED; - goto out_error; + /* Only fail here for a real V5 filesystem */ + if (bp->b_bn != XFS_SB_DADDR && + xfs_sb_version_hascrc(&mp->m_sb)) { + error = EFSCORRUPTED; + goto out_error; + } } } error = xfs_sb_verify(bp, true); _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs