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_HELO_NONE,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 26390C2BCA1 for ; Fri, 7 Jun 2019 19:17:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 088BB2083D for ; Fri, 7 Jun 2019 19:17:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729920AbfFGTRu (ORCPT ); Fri, 7 Jun 2019 15:17:50 -0400 Received: from gateway34.websitewelcome.com ([192.185.148.231]:18516 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728752AbfFGTRt (ORCPT ); Fri, 7 Jun 2019 15:17:49 -0400 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway34.websitewelcome.com (Postfix) with ESMTP id 4A5843BA94 for ; Fri, 7 Jun 2019 14:17:49 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id ZKN3hERzc2PzOZKN3hYGDZ; Fri, 07 Jun 2019 14:17:49 -0500 X-Authority-Reason: nr=8 Received: from [189.250.134.24] (port=48016 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1hZKN1-002mT3-Kl; Fri, 07 Jun 2019 14:17:48 -0500 Date: Fri, 7 Jun 2019 14:17:45 -0500 From: "Gustavo A. R. Silva" To: Igor Mitsyanko , Avinash Patil , Sergey Matyukevich , 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] qtnfmac: Use struct_size() in kzalloc() Message-ID: <20190607191745.GA19120@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: 189.250.134.24 X-Source-L: No X-Exim-ID: 1hZKN1-002mT3-Kl X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.134.24]:48016 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 7 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 ieee80211_regdomain { ... struct ieee80211_reg_rule reg_rules[]; }; instance = kzalloc(sizeof(*mac->rd) + sizeof(struct ieee80211_reg_rule) * 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, reg_rules, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/net/wireless/quantenna/qtnfmac/commands.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/quantenna/qtnfmac/commands.c b/drivers/net/wireless/quantenna/qtnfmac/commands.c index 459f6b81d2eb..dc0c7244b60e 100644 --- a/drivers/net/wireless/quantenna/qtnfmac/commands.c +++ b/drivers/net/wireless/quantenna/qtnfmac/commands.c @@ -1011,9 +1011,8 @@ qtnf_parse_variable_mac_info(struct qtnf_wmac *mac, if (WARN_ON(resp->n_reg_rules > NL80211_MAX_SUPP_REG_RULES)) return -E2BIG; - mac->rd = kzalloc(sizeof(*mac->rd) + - sizeof(struct ieee80211_reg_rule) * - resp->n_reg_rules, GFP_KERNEL); + mac->rd = kzalloc(struct_size(mac->rd, reg_rules, resp->n_reg_rules), + GFP_KERNEL); if (!mac->rd) return -ENOMEM; -- 2.21.0