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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 02446C433F4 for ; Sun, 26 Aug 2018 19:20:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8AB3120893 for ; Sun, 26 Aug 2018 19:20:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AB3120893 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=embeddedor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726875AbeHZXD2 (ORCPT ); Sun, 26 Aug 2018 19:03:28 -0400 Received: from gateway30.websitewelcome.com ([192.185.152.11]:47927 "EHLO gateway30.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726643AbeHZXD2 (ORCPT ); Sun, 26 Aug 2018 19:03:28 -0400 X-Greylist: delayed 1973 seconds by postgrey-1.27 at vger.kernel.org; Sun, 26 Aug 2018 19:03:28 EDT Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway30.websitewelcome.com (Postfix) with ESMTP id BFB7234E4 for ; Sun, 26 Aug 2018 13:47:13 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id u049fLXV9BcCXu049fqQgy; Sun, 26 Aug 2018 13:47:13 -0500 X-Authority-Reason: nr=8 Received: from [189.250.132.202] (port=46808 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1fu048-003zfG-Vs; Sun, 26 Aug 2018 13:47:13 -0500 Date: Sun, 26 Aug 2018 13:47:12 -0500 From: "Gustavo A. R. Silva" To: Sandy Huang , Heiko =?iso-8859-1?Q?St=FCbner?= , David Airlie Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Kees Cook , "Gustavo A. R. Silva" Subject: [PATCH] drm/rockchip: Use struct_size() in devm_kzalloc() Message-ID: <20180826184712.GA9330@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) 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: 189.250.132.202 X-Source-L: No X-Exim-ID: 1fu048-003zfG-Vs X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.132.202]:46808 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 7 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 One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); or, like in this particular case: size = sizeof(struct foo) + sizeof(void *) * count; instance = devm_kzalloc(dev, size, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index 1359e5c..cf64e4d 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -1561,7 +1562,6 @@ static int vop_bind(struct device *dev, struct device *master, void *data) struct drm_device *drm_dev = data; struct vop *vop; struct resource *res; - size_t alloc_size; int ret, irq; vop_data = of_device_get_match_data(dev); @@ -1569,8 +1569,8 @@ static int vop_bind(struct device *dev, struct device *master, void *data) return -ENODEV; /* Allocate vop struct and its vop_win array */ - alloc_size = sizeof(*vop) + sizeof(*vop->win) * vop_data->win_size; - vop = devm_kzalloc(dev, alloc_size, GFP_KERNEL); + vop = devm_kzalloc(dev, struct_size(vop, win, vop_data->win_size), + GFP_KERNEL); if (!vop) return -ENOMEM; -- 2.7.4