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_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 98668C43387 for ; Fri, 4 Jan 2019 18:43:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 68AE121872 for ; Fri, 4 Jan 2019 18:43:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726983AbfADSn0 (ORCPT ); Fri, 4 Jan 2019 13:43:26 -0500 Received: from gateway36.websitewelcome.com ([192.185.193.12]:47225 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726405AbfADSnZ (ORCPT ); Fri, 4 Jan 2019 13:43:25 -0500 Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway36.websitewelcome.com (Postfix) with ESMTP id BD1FF400C7484 for ; Fri, 4 Jan 2019 11:55:13 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id fURJgP0yLYTGMfURJgBFKM; Fri, 04 Jan 2019 12:43:25 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=36838 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gfURI-0018l2-Mb; Fri, 04 Jan 2019 12:43:25 -0600 Date: Fri, 4 Jan 2019 12:43:22 -0600 From: "Gustavo A. R. Silva" To: Patrice Chotard , Vinod Koul , Dan Williams Cc: linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] dmaengine: st_fdma: use struct_size() in kzalloc() Message-ID: <20190104184322.GA9615@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: 189.250.130.205 X-Source-L: No X-Exim-ID: 1gfURI-0018l2-Mb X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:36838 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 47 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 = kzalloc(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 = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/dma/st_fdma.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/dma/st_fdma.c b/drivers/dma/st_fdma.c index 07c20aa2e955..df6b73028ecb 100644 --- a/drivers/dma/st_fdma.c +++ b/drivers/dma/st_fdma.c @@ -243,8 +243,7 @@ static struct st_fdma_desc *st_fdma_alloc_desc(struct st_fdma_chan *fchan, struct st_fdma_desc *fdesc; int i; - fdesc = kzalloc(sizeof(*fdesc) + - sizeof(struct st_fdma_sw_node) * sg_len, GFP_NOWAIT); + fdesc = kzalloc(struct_size(fdesc, node, sg_len), GFP_NOWAIT); if (!fdesc) return NULL; -- 2.20.1