From patchwork Fri Jun 7 19:17:45 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: 10982675 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 03A886C5 for ; Fri, 7 Jun 2019 19:40:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E6C9928A8C for ; Fri, 7 Jun 2019 19:40:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D54CB28B68; Fri, 7 Jun 2019 19:40:07 +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 5ED1128A8C for ; Fri, 7 Jun 2019 19:40:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730326AbfFGTkG (ORCPT ); Fri, 7 Jun 2019 15:40:06 -0400 Received: from gateway30.websitewelcome.com ([192.185.160.12]:28463 "EHLO gateway30.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729809AbfFGTkG (ORCPT ); Fri, 7 Jun 2019 15:40:06 -0400 X-Greylist: delayed 1336 seconds by postgrey-1.27 at vger.kernel.org; Fri, 07 Jun 2019 15:40:05 EDT Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway30.websitewelcome.com (Postfix) with ESMTP id 3200A10295 for ; Fri, 7 Jun 2019 14:17:49 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id ZKN3hJcKj4FKpZKN3hd8lT; 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-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: 6 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 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 Reviewed-by: Sergey Matyukevich --- 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;