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,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=unavailable 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 E1040C4360F for ; Wed, 3 Apr 2019 16:41:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B4CAC2082C for ; Wed, 3 Apr 2019 16:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726536AbfDCQk4 (ORCPT ); Wed, 3 Apr 2019 12:40:56 -0400 Received: from gateway34.websitewelcome.com ([192.185.149.222]:25824 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726084AbfDCQkz (ORCPT ); Wed, 3 Apr 2019 12:40:55 -0400 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway34.websitewelcome.com (Postfix) with ESMTP id AF89C109723A for ; Wed, 3 Apr 2019 11:40:54 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id BiwYhaLGy2PzOBiwYhBuVC; Wed, 03 Apr 2019 11:40:54 -0500 X-Authority-Reason: nr=8 Received: from [189.250.114.183] (port=42224 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hBiwX-001ZIn-Lm; Wed, 03 Apr 2019 11:40:53 -0500 Date: Wed, 3 Apr 2019 11:40:52 -0500 From: "Gustavo A. R. Silva" To: Amitkumar Karwar , Nishant Sarmukadam , Ganapathi Bhat , Xinming Hu , Kalle Valo , "David S. Miller" Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] mwifiex: use struct_size() in kzalloc() Message-ID: <20190403164052.GA26381@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: 189.250.114.183 X-Source-L: No X-Exim-ID: 1hBiwX-001ZIn-Lm X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.114.183]:42224 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 17 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@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; struct boo entry[]; }; size = sizeof(struct foo) + count * sizeof(struct boo); instance = kzalloc(size, 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) Notice that, in this case, variable regd_size is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c b/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c index 69e3b624adbb..24b33e20e7a9 100644 --- a/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c +++ b/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c @@ -1025,17 +1025,14 @@ mwifiex_create_custom_regdomain(struct mwifiex_private *priv, struct ieee80211_regdomain *regd; struct ieee80211_reg_rule *rule; bool new_rule; - int regd_size, idx, freq, prev_freq = 0; + int idx, freq, prev_freq = 0; u32 bw, prev_bw = 0; u8 chflags, prev_chflags = 0, valid_rules = 0; if (WARN_ON_ONCE(num_chan > NL80211_MAX_SUPP_REG_RULES)) return ERR_PTR(-EINVAL); - regd_size = sizeof(struct ieee80211_regdomain) + - num_chan * sizeof(struct ieee80211_reg_rule); - - regd = kzalloc(regd_size, GFP_KERNEL); + regd = kzalloc(struct_size(regd, reg_rules, num_chan), GFP_KERNEL); if (!regd) return ERR_PTR(-ENOMEM); -- 2.21.0