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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 1D399C28CC5 for ; Wed, 5 Jun 2019 23:55:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC3AA20866 for ; Wed, 5 Jun 2019 23:55:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726732AbfFEXzr (ORCPT ); Wed, 5 Jun 2019 19:55:47 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:42494 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726510AbfFEXzq (ORCPT ); Wed, 5 Jun 2019 19:55:46 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 1D041136E16AB; Wed, 5 Jun 2019 16:55:46 -0700 (PDT) Date: Wed, 05 Jun 2019 16:55:45 -0700 (PDT) Message-Id: <20190605.165545.1484056704164319975.davem@davemloft.net> To: gustavo@embeddedor.com Cc: jakub.kicinski@netronome.com, oss-drivers@netronome.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][next] nfp: flower: use struct_size() helper From: David Miller In-Reply-To: <20190605203827.GA22786@embeddedor> References: <20190605203827.GA22786@embeddedor> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Wed, 05 Jun 2019 16:55:46 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Gustavo A. R. Silva" Date: Wed, 5 Jun 2019 15:38:27 -0500 > 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 nfp_tun_active_tuns { > ... > struct route_ip_info { > __be32 ipv4; > __be32 egress_port; > __be32 extra[2]; > } tun_info[]; > }; > > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes. > > So, replace the following form: > > sizeof(struct nfp_tun_active_tuns) + sizeof(struct route_ip_info) * count > > with: > > struct_size(payload, tun_info, count) > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva Applied.