From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp2130.oracle.com ([156.151.31.86]:47436 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751367AbeFDEcZ (ORCPT ); Mon, 4 Jun 2018 00:32:25 -0400 Date: Sun, 3 Jun 2018 21:32:21 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH 07/10] xfs: xfs_alloc_get_rec should return EFSCORRUPTED for obvious bnobt corruption Message-ID: <20180604043221.GN7825@magnolia> References: <152806814253.18187.4009340462930782844.stgit@magnolia> <152806818878.18187.4844773238575124410.stgit@magnolia> <20180604001406.GE10363@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180604001406.GE10363@dastard> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Dave Chinner Cc: linux-xfs@vger.kernel.org On Mon, Jun 04, 2018 at 10:14:06AM +1000, Dave Chinner wrote: > On Sun, Jun 03, 2018 at 04:23:08PM -0700, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > Return -EFSCORRUPTED when the bnobt/cntbt return obviously corrupt > > values, rather than letting them bounce around in the internal code. > > > > Signed-off-by: Darrick J. Wong > > --- > > fs/xfs/libxfs/xfs_alloc.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > > > diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c > > index dc9dd3805d97..0214a77808d0 100644 > > --- a/fs/xfs/libxfs/xfs_alloc.c > > +++ b/fs/xfs/libxfs/xfs_alloc.c > > @@ -231,10 +231,14 @@ xfs_alloc_get_rec( > > int error; > > > > error = xfs_btree_get_rec(cur, &rec, stat); > > - if (!error && *stat == 1) { > > - *bno = be32_to_cpu(rec->alloc.ar_startblock); > > - *len = be32_to_cpu(rec->alloc.ar_blockcount); > > - } > > + if (error || !(*stat)) > > + return error; > > + if (rec->alloc.ar_blockcount == 0) > > + return -EFSCORRUPTED; > > + > > + *bno = be32_to_cpu(rec->alloc.ar_startblock); > > + *len = be32_to_cpu(rec->alloc.ar_blockcount); > > Looks good, but makes me wonder if we should verify that > ar_startblock is a valid agbno, and that the extent lies wholly > within the AG? That can be another patch, though. We probably ought to fix all the _get_rec functions to check that they're not returning obviously garbage results. --D > Reviewed-by: Dave Chinner > > Cheers, > > Dave. > > -- > Dave Chinner > david@fromorbit.com > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html