From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:40422 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933194AbeF1J2m (ORCPT ); Thu, 28 Jun 2018 05:28:42 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BBFD4814FDCF for ; Thu, 28 Jun 2018 09:28:41 +0000 (UTC) Received: from odin.usersys.redhat.com (ovpn-204-57.brq.redhat.com [10.40.204.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id 20DD51C71C for ; Thu, 28 Jun 2018 09:28:40 +0000 (UTC) From: Carlos Maiolino Subject: [PATCH V2] xfs: Initialize variables in xfs_alloc_get_rec before using them Date: Thu, 28 Jun 2018 11:28:35 +0200 Message-Id: <20180628092835.25879-1-cmaiolino@redhat.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: linux-xfs@vger.kernel.org Make sure we initialize *bno and *len, before jumping to out_bad_rec label, and risk calling xfs_warn() with uninitialized variables. Coverity: 100898 Coverity: 1437081 Coverity: 1437129 Coverity: 1437191 Coverity: 1437201 Coverity: 1437212 Coverity: 1437341 Signed-off-by: Carlos Maiolino --- This is based on Darrick's suggestion, although, I believe initializing *bno and *len before testing if *len is empty or not is a bit more clear than changing xfs_warn() to use rec->alloc.ar_startblock and rec->alloc.ar_blockcount directly. fs/xfs/libxfs/xfs_alloc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index eef466260d43..75dbdc14c45f 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -223,12 +223,13 @@ xfs_alloc_get_rec( error = xfs_btree_get_rec(cur, &rec, stat); if (error || !(*stat)) return error; - if (rec->alloc.ar_blockcount == 0) - goto out_bad_rec; *bno = be32_to_cpu(rec->alloc.ar_startblock); *len = be32_to_cpu(rec->alloc.ar_blockcount); + if (*len == 0) + goto out_bad_rec; + /* check for valid extent range, including overflow */ if (!xfs_verify_agbno(mp, agno, *bno)) goto out_bad_rec; -- 2.14.3