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=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 85EFEC282C2 for ; Fri, 8 Feb 2019 00:59:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FA602085A for ; Fri, 8 Feb 2019 00:59:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726860AbfBHA66 (ORCPT ); Thu, 7 Feb 2019 19:58:58 -0500 Received: from gateway24.websitewelcome.com ([192.185.51.228]:31773 "EHLO gateway24.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726676AbfBHA66 (ORCPT ); Thu, 7 Feb 2019 19:58:58 -0500 Received: from cm14.websitewelcome.com (cm14.websitewelcome.com [100.42.49.7]) by gateway24.websitewelcome.com (Postfix) with ESMTP id ED2D193BF6 for ; Thu, 7 Feb 2019 18:58:57 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id ruVNg5Fk52qH7ruVNgeIDs; Thu, 07 Feb 2019 18:58:57 -0600 X-Authority-Reason: nr=8 Received: from [189.250.49.191] (port=47634 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gruVN-004EX0-6Q; Thu, 07 Feb 2019 18:58:57 -0600 Date: Thu, 7 Feb 2019 18:58:56 -0600 From: "Gustavo A. R. Silva" To: Roopa Prabhu , Nikolay Aleksandrov , "David S. Miller" Cc: bridge@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH net-next] bridge: use struct_size() helper Message-ID: <20190208005856.GA16642@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: 189.250.49.191 X-Source-L: No X-Exim-ID: 1gruVN-004EX0-6Q X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.49.191]:47634 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 37 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 = alloc(size, GFP_KERNEL) Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: size = struct_size(instance, entry, count); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- net/bridge/br_multicast.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 1fb885a33c66..4a048fd1cbea 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1018,8 +1018,7 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, if (!nsrcs) return -EINVAL; - grec_len = sizeof(*grec) + - sizeof(struct in6_addr) * ntohs(*nsrcs); + grec_len = struct_size(grec, grec_src, ntohs(*nsrcs)); if (!ipv6_mc_may_pull(skb, len + grec_len)) return -EINVAL; -- 2.20.1