From patchwork Fri Jan 4 17:37:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 1020840 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=embeddedor.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43WXcj0t5Mz9s55 for ; Sat, 5 Jan 2019 05:00:05 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726480AbfADSAE (ORCPT ); Fri, 4 Jan 2019 13:00:04 -0500 Received: from gateway30.websitewelcome.com ([192.185.147.85]:17789 "EHLO gateway30.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726282AbfADSAD (ORCPT ); Fri, 4 Jan 2019 13:00:03 -0500 X-Greylist: delayed 1344 seconds by postgrey-1.27 at vger.kernel.org; Fri, 04 Jan 2019 13:00:03 EST Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway30.websitewelcome.com (Postfix) with ESMTP id F121F9123 for ; Fri, 4 Jan 2019 11:37:38 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id fTPegO39qYTGMfTPegAI9E; Fri, 04 Jan 2019 11:37:38 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=35296 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gfTPe-000SB1-7D; Fri, 04 Jan 2019 11:37:38 -0600 Date: Fri, 4 Jan 2019 11:37:33 -0600 From: "Gustavo A. R. Silva" To: Linus Walleij Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] pinctrl: mcp23s08: use struct_size() in devm_kzalloc() Message-ID: <20190104173733.GA29979@embeddedor> MIME-Version: 1.0 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: 189.250.130.205 X-Source-L: No X-Exim-ID: 1gfTPe-000SB1-7D X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:35296 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 32 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@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 code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/pinctrl/pinctrl-mcp23s08.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/pinctrl/pinctrl-mcp23s08.c b/drivers/pinctrl/pinctrl-mcp23s08.c index b03481ef99a1..6b4def13df8f 100644 --- a/drivers/pinctrl/pinctrl-mcp23s08.c +++ b/drivers/pinctrl/pinctrl-mcp23s08.c @@ -1139,8 +1139,7 @@ static int mcp23s08_probe(struct spi_device *spi) return -ENODEV; data = devm_kzalloc(&spi->dev, - sizeof(*data) + chips * sizeof(struct mcp23s08), - GFP_KERNEL); + struct_size(data, chip, chips), GFP_KERNEL); if (!data) return -ENOMEM;