From patchwork Wed Apr 3 16:40:52 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: 10884249 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EDF1D13B5 for ; Wed, 3 Apr 2019 17:02:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D77922881C for ; Wed, 3 Apr 2019 17:02:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CBC06289C0; Wed, 3 Apr 2019 17:02:01 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E1AD72881C for ; Wed, 3 Apr 2019 17:01:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726184AbfDCRB6 (ORCPT ); Wed, 3 Apr 2019 13:01:58 -0400 Received: from gateway31.websitewelcome.com ([192.185.143.234]:49155 "EHLO gateway31.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726084AbfDCRB6 (ORCPT ); Wed, 3 Apr 2019 13:01:58 -0400 X-Greylist: delayed 1263 seconds by postgrey-1.27 at vger.kernel.org; Wed, 03 Apr 2019 13:01:58 EDT Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway31.websitewelcome.com (Postfix) with ESMTP id AA3A1D53F5 for ; Wed, 3 Apr 2019 11:40:54 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id BiwYhlwnJ4FKpBiwYhHjyt; 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-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: 16 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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);