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_HELO_NONE,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 C1B96C28CC5 for ; Wed, 5 Jun 2019 21:09:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9511D2075B for ; Wed, 5 Jun 2019 21:09:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726786AbfFEVJl (ORCPT ); Wed, 5 Jun 2019 17:09:41 -0400 Received: from gateway20.websitewelcome.com ([192.185.59.4]:17298 "EHLO gateway20.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbfFEVJk (ORCPT ); Wed, 5 Jun 2019 17:09:40 -0400 X-Greylist: delayed 1210 seconds by postgrey-1.27 at vger.kernel.org; Wed, 05 Jun 2019 17:09:40 EDT Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway20.websitewelcome.com (Postfix) with ESMTP id B16BC400CCA3D for ; Wed, 5 Jun 2019 14:48:46 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id Ycqfh3i8y90onYcqfh5OHF; Wed, 05 Jun 2019 15:49:29 -0500 X-Authority-Reason: nr=8 Received: from [189.250.127.120] (port=34964 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hYcqe-0046eo-D3; Wed, 05 Jun 2019 15:49:28 -0500 Date: Wed, 5 Jun 2019 15:49:26 -0500 From: "Gustavo A. R. Silva" To: Mark Fasheh , Joel Becker , Joseph Qi Cc: ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] ocfs2/dlm: use struct_size() helper Message-ID: <20190605204926.GA24467@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: 189.250.127.120 X-Source-L: No X-Exim-ID: 1hYcqe-0046eo-D3 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.127.120]:34964 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 21 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 dlm_migratable_lockres { i ... struct dlm_migratable_lock ml[0]; // 16 bytes each, begins at byte 112 }; 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 dlm_migratable_lockres) + (mres->num_locks * sizeof(struct dlm_migratable_lock)) with: struct_size(mres, ml, mres->num_locks) Notice that, in this case, variable sz is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- fs/ocfs2/dlm/dlmrecovery.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index e22d6a115220..064ce5bbc3f6 100644 --- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1109,7 +1109,7 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, { u64 mig_cookie = be64_to_cpu(mres->mig_cookie); int mres_total_locks = be32_to_cpu(mres->total_locks); - int sz, ret = 0, status = 0; + int ret = 0, status = 0; u8 orig_flags = mres->flags, orig_master = mres->master; @@ -1117,9 +1117,6 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, if (!mres->num_locks) return 0; - sz = sizeof(struct dlm_migratable_lockres) + - (mres->num_locks * sizeof(struct dlm_migratable_lock)); - /* add an all-done flag if we reached the last lock */ orig_flags = mres->flags; BUG_ON(total_locks > mres_total_locks); @@ -1133,7 +1130,8 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, /* send it */ ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres, - sz, send_to, &status); + struct_size(mres, ml, mres->num_locks), + send_to, &status); if (ret < 0) { /* XXX: negative status is not handled. * this will end up killing this node. */ -- 2.21.0