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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 D405FC3A5A3 for ; Thu, 29 Aug 2019 19:06:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 98A5022CEA for ; Thu, 29 Aug 2019 19:06:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=embeddedor.com header.i=@embeddedor.com header.b="ln7FlWdW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98A5022CEA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=embeddedor.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2EE916B0008; Thu, 29 Aug 2019 15:06:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 278F76B000C; Thu, 29 Aug 2019 15:06:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 166516B000D; Thu, 29 Aug 2019 15:06:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0239.hostedemail.com [216.40.44.239]) by kanga.kvack.org (Postfix) with ESMTP id E440F6B0008 for ; Thu, 29 Aug 2019 15:06:09 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 9773D181AC9B4 for ; Thu, 29 Aug 2019 19:06:09 +0000 (UTC) X-FDA: 75876395658.16.farm41_52d1b8bbb055c X-HE-Tag: farm41_52d1b8bbb055c X-Filterd-Recvd-Size: 4069 Received: from gateway33.websitewelcome.com (gateway33.websitewelcome.com [192.185.145.216]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Thu, 29 Aug 2019 19:06:08 +0000 (UTC) Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway33.websitewelcome.com (Postfix) with ESMTP id 4300ED982B for ; Thu, 29 Aug 2019 14:06:08 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 3PkFiyZPliQer3PkGiHtJo; Thu, 29 Aug 2019 14:06:08 -0500 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Type:MIME-Version:Message-ID:Subject: Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=3+46xOrI9yy3LuOhJZ5rmqfr4aF7buwsYetlbyfyvSU=; b=ln7FlWdWq1Un9s4oy/dP68rvSQ TJnWL2hfqTjoz+3qyEAHw1M9p5TVCgHJRS6FIjDUkVoB5Fp1Xg53bPK6GKtekC+PflgtgtZ776Tdy N8sXXKpmhMhZTMKYKA1Vm0WRGA/VnWDby8hTFEhZHMK2Eegh8898DUK5y06xj/frawbEm+v6KrZNd 8a9tJLkqK9os6hZf24ajT6J0HAP6o5V9WF8LEX39ksicjtpwh6M7MaOSRv98v9qJQC6CE2Mkngo7G OZzfg+M8OqxIhqsa6eraB1bLfGSd8UwnPQ3fDm1j03dHFO1C3wKWII3ibEx3uYpgAoPHkqdhrkBxA aH2p7BdQ==; Received: from [189.152.216.116] (port=45156 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1i3PkE-001rxt-Vo; Thu, 29 Aug 2019 14:06:07 -0500 Date: Thu, 29 Aug 2019 14:06:05 -0500 From: "Gustavo A. R. Silva" To: Dennis Zhou , Tejun Heo , Christoph Lameter Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] percpu: Use struct_size() helper Message-ID: <20190829190605.GA17425@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 - kvack.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.152.216.116 X-Source-L: No X-Exim-ID: 1i3PkE-001rxt-Vo X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.152.216.116]:45156 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 4 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-Bogosity: Ham, tests=bogofilter, spamicity=0.000002, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 pcpu_alloc_info { ... struct pcpu_group_info groups[]; }; 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(*ai) + nr_groups * sizeof(ai->groups[0]) with: struct_size(ai, groups, nr_groups) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- mm/percpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/percpu.c b/mm/percpu.c index 7e2aa0305c27..7e06a1e58720 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -2125,7 +2125,7 @@ struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, void *ptr; int unit; - base_size = ALIGN(sizeof(*ai) + nr_groups * sizeof(ai->groups[0]), + base_size = ALIGN(struct_size(ai, groups, nr_groups), __alignof__(ai->groups[0].cpu_map[0])); ai_size = base_size + nr_units * sizeof(ai->groups[0].cpu_map[0]); -- 2.23.0