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=-2.5 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 CCD2DC4321D for ; Fri, 24 Aug 2018 01:05:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 604AF21557 for ; Fri, 24 Aug 2018 01:05:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 604AF21557 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 S1726808AbeHXEhh (ORCPT ); Fri, 24 Aug 2018 00:37:37 -0400 Received: from gateway22.websitewelcome.com ([192.185.46.187]:36915 "EHLO gateway22.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725945AbeHXEhh (ORCPT ); Fri, 24 Aug 2018 00:37:37 -0400 Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway22.websitewelcome.com (Postfix) with ESMTP id 9FD38EE5A for ; Thu, 23 Aug 2018 20:05:23 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id t0XTfrLOH79N3t0XTf6kSX; Thu, 23 Aug 2018 20:05:23 -0500 X-Authority-Reason: nr=8 Received: from [189.250.73.28] (port=44058 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1ft0XS-003QEE-Tr; Thu, 23 Aug 2018 20:05:23 -0500 Date: Thu, 23 Aug 2018 20:05:21 -0500 From: "Gustavo A. R. Silva" To: Maxime Ripard , David Airlie , Chen-Yu Tsai Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Kees Cook , "Gustavo A. R. Silva" Subject: [PATCH] drm/sun4i: tcon-top: Use struct_size() in devm_kzalloc() Message-ID: <20180824010521.GA25451@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: 189.250.73.28 X-Source-L: No X-Exim-ID: 1ft0XS-003QEE-Tr X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.73.28]:44058 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 6 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); 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/sun4i/sun8i_tcon_top.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/sun4i/sun8i_tcon_top.c b/drivers/gpu/drm/sun4i/sun8i_tcon_top.c index 55fe398..3040a79 100644 --- a/drivers/gpu/drm/sun4i/sun8i_tcon_top.c +++ b/drivers/gpu/drm/sun4i/sun8i_tcon_top.c @@ -129,8 +129,7 @@ static int sun8i_tcon_top_bind(struct device *dev, struct device *master, if (!tcon_top) return -ENOMEM; - clk_data = devm_kzalloc(dev, sizeof(*clk_data) + - sizeof(*clk_data->hws) * CLK_NUM, + clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, CLK_NUM), GFP_KERNEL); if (!clk_data) return -ENOMEM; -- 2.7.4