Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757829Ab2HHHWN (ORCPT ); Wed, 8 Aug 2012 03:22:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12873 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757548Ab2HHHWK (ORCPT ); Wed, 8 Aug 2012 03:22:10 -0400 Date: Wed, 8 Aug 2012 09:22:01 +0200 (CEST) From: =?ISO-8859-15?Q?Luk=E1=A8_Czerner?= X-X-Sender: lukas@localhost To: Tomas Racek cc: linux-xfs@vger.kernel.org, lczerner@redhat.com, Ben Myers , Alex Elder , "supporter:XFS FILESYSTEM" , open list Subject: Re: [PATCH v2] xfs: check for possible overflow in xfs_ioc_trim In-Reply-To: <1343828737-5324-1-git-send-email-tracek@redhat.com> Message-ID: References: <1343828737-5324-1-git-send-email-tracek@redhat.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2034 Lines: 60 On Wed, 1 Aug 2012, Tomas Racek wrote: > Date: Wed, 1 Aug 2012 15:45:37 +0200 > From: Tomas Racek > To: linux-xfs@vger.kernel.org > Cc: lczerner@redhat.com, Tomas Racek , > Ben Myers , Alex Elder , > "supporter:XFS FILESYSTEM" , > open list > Subject: [PATCH v2] xfs: check for possible overflow in xfs_ioc_trim > > If range.start points behind the filesystem, return invalid value error. > This fixes possible overflow in > > start = BTOBB(range.start) > > when range.start is nearly ULLONG_MAX. > > Signed-off-by: Tomas Racek The fix looks good to me, but I have one comment bellow. > --- > fs/xfs/xfs_discard.c | 5 +++-- > 1 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c > index f9c3fe3..33d367f 100644 > --- a/fs/xfs/xfs_discard.c > +++ b/fs/xfs/xfs_discard.c > @@ -179,12 +179,13 @@ xfs_ioc_trim( > * used by the fstrim application. In the end it really doesn't > * matter as trimming blocks is an advisory interface. > */ > + if (range.start >= XFS_FSB_TO_B(mp, mp->m_sb.sb_dblocks)) > + return -XFS_ERROR(EINVAL); > + > start = BTOBB(range.start); > end = start + BTOBBT(range.len) - 1; > minlen = BTOBB(max_t(u64, granularity, range.minlen)); It seems that we have the same problem here with range.minlen. It is highly unlikely and stupid from the user space to send minlen of such size, but it is possible. Thanks! -Lukas > > - if (XFS_BB_TO_FSB(mp, start) >= mp->m_sb.sb_dblocks) > - return -XFS_ERROR(EINVAL); > if (end > XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks) - 1) > end = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)- 1; > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/