From patchwork Fri Oct 13 11:05:01 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 10004163 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B1494602B3 for ; Fri, 13 Oct 2017 11:05:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A429D2902B for ; Fri, 13 Oct 2017 11:05:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 991462902D; Fri, 13 Oct 2017 11:05:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D5F12902C for ; Fri, 13 Oct 2017 11:05:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757925AbdJMLFN (ORCPT ); Fri, 13 Oct 2017 07:05:13 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:23659 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751529AbdJMLFM (ORCPT ); Fri, 13 Oct 2017 07:05:12 -0400 Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id v9DB5946029982 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Oct 2017 11:05:09 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id v9DB59FK006540 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Oct 2017 11:05:09 GMT Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id v9DB58hg015619; Fri, 13 Oct 2017 11:05:09 GMT Received: from mwanda (/197.254.35.146) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 13 Oct 2017 04:05:08 -0700 Date: Fri, 13 Oct 2017 14:05:01 +0300 From: Dan Carpenter To: Alex Williamson Cc: kvm@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] vfio/type1: silence integer overflow warning Message-ID: <20171013110500.6apnjjw67lnvhlrk@mwanda> MIME-Version: 1.0 Content-Disposition: inline X-Mailer: git-send-email haha only kidding User-Agent: NeoMutt/20170609 (1.8.3) X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP I get a static checker warning about the potential integer overflow if we add "unmap->iova + unmap->size". The integer overflow isn't really harmful, but we may as well fix it. Also unmap->size gets truncated to size_t when we pass it to vfio_find_dma() so we could check for too high values of that as well. Signed-off-by: Dan Carpenter diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 92155cce926d..89d50aeafd71 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -767,6 +767,9 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, return -EINVAL; if (!unmap->size || unmap->size & mask) return -EINVAL; + if (unmap->iova + unmap->size < unmap->iova || + unmap->size > SIZE_MAX) + return -EINVAL; WARN_ON(mask & PAGE_MASK); again: