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 2B8A1C10F13 for ; Thu, 11 Apr 2019 23:43:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E48FC2146F for ; Thu, 11 Apr 2019 23:43:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727097AbfDKXnI (ORCPT ); Thu, 11 Apr 2019 19:43:08 -0400 Received: from gateway24.websitewelcome.com ([192.185.50.252]:43035 "EHLO gateway24.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726800AbfDKXnI (ORCPT ); Thu, 11 Apr 2019 19:43:08 -0400 Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway24.websitewelcome.com (Postfix) with ESMTP id 9449074920 for ; Thu, 11 Apr 2019 18:43:07 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id EjLXh0rya4FKpEjLXhV58c; Thu, 11 Apr 2019 18:43:07 -0500 X-Authority-Reason: nr=8 Received: from [189.250.139.70] (port=33350 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hEjLW-001spb-Qo; Thu, 11 Apr 2019 18:43:06 -0500 Date: Thu, 11 Apr 2019 18:43:06 -0500 From: "Gustavo A. R. Silva" To: Thomas Graf , Herbert Xu Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] rhashtable: use struct_size() in kvzalloc() Message-ID: <20190411234306.GA20668@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: 189.250.139.70 X-Source-L: No X-Exim-ID: 1hEjLW-001spb-Qo X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.139.70]:33350 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 6 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 = kvzalloc(size, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kvzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- lib/rhashtable.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index a8583af43b59..9c84f5cef69c 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -175,8 +175,7 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht, int i; static struct lock_class_key __key; - size = sizeof(*tbl) + nbuckets * sizeof(tbl->buckets[0]); - tbl = kvzalloc(size, gfp); + tbl = kvzalloc(struct_size(tbl, buckets, nbuckets), gfp); size = nbuckets; -- 2.21.0