From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B67DAC072B5 for ; Fri, 24 May 2019 17:14:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9017F20863 for ; Fri, 24 May 2019 17:14:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731784AbfEXROm (ORCPT ); Fri, 24 May 2019 13:14:42 -0400 Received: from gateway21.websitewelcome.com ([192.185.45.212]:36236 "EHLO gateway21.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725777AbfEXROm (ORCPT ); Fri, 24 May 2019 13:14:42 -0400 Received: from cm14.websitewelcome.com (cm14.websitewelcome.com [100.42.49.7]) by gateway21.websitewelcome.com (Postfix) with ESMTP id 0799E400C9F2B for ; Fri, 24 May 2019 12:14:41 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id UDmChalYp2qH7UDmChpTPl; Fri, 24 May 2019 12:14:41 -0500 X-Authority-Reason: nr=8 Received: from [189.250.47.159] (port=51574 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hUDlt-002A7a-UC; Fri, 24 May 2019 12:14:39 -0500 Date: Fri, 24 May 2019 12:14:21 -0500 From: "Gustavo A. R. Silva" To: Zhenyu Wang , Zhi Wang , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter Cc: intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] drm/i915/kvmgt: Use struct_size() helper Message-ID: <20190524171421.GA20808@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.47.159 X-Source-L: No X-Exim-ID: 1hUDlt-002A7a-UC X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.47.159]:51574 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 11 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes, in particular in the context in which this code is being used. So, replace the following form: sizeof(*sparse) + (nr_areas * sizeof(*sparse->areas) with: struct_size(sparse, areas, sparse->nr_areas) and so on... Also, notice that variable size is unnecessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/i915/gvt/kvmgt.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index 144301b778df..9674738b89df 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -1306,7 +1306,6 @@ static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd, unsigned int i; int ret; struct vfio_region_info_cap_sparse_mmap *sparse = NULL; - size_t size; int nr_areas = 1; int cap_type_id; @@ -1349,9 +1348,8 @@ static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd, VFIO_REGION_INFO_FLAG_WRITE; info.size = gvt_aperture_sz(vgpu->gvt); - size = sizeof(*sparse) + - (nr_areas * sizeof(*sparse->areas)); - sparse = kzalloc(size, GFP_KERNEL); + sparse = kzalloc(struct_size(sparse, areas, nr_areas), + GFP_KERNEL); if (!sparse) return -ENOMEM; @@ -1416,9 +1414,9 @@ static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd, switch (cap_type_id) { case VFIO_REGION_INFO_CAP_SPARSE_MMAP: ret = vfio_info_add_capability(&caps, - &sparse->header, sizeof(*sparse) + - (sparse->nr_areas * - sizeof(*sparse->areas))); + &sparse->header, + struct_size(sparse, areas, + sparse->nr_areas)); if (ret) { kfree(sparse); return ret; -- 2.21.0