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=unavailable 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 36CD8C169C4 for ; Fri, 8 Feb 2019 03:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1069221907 for ; Fri, 8 Feb 2019 03:42:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726882AbfBHDmp (ORCPT ); Thu, 7 Feb 2019 22:42:45 -0500 Received: from gateway31.websitewelcome.com ([192.185.143.5]:47904 "EHLO gateway31.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726718AbfBHDmp (ORCPT ); Thu, 7 Feb 2019 22:42:45 -0500 Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway31.websitewelcome.com (Postfix) with ESMTP id 0618F265379 for ; Thu, 7 Feb 2019 21:42:44 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id rx3rgNsZrdnCerx3sgNuot; Thu, 07 Feb 2019 21:42:44 -0600 X-Authority-Reason: nr=8 Received: from [189.250.49.191] (port=49408 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1grx3r-001met-8v; Thu, 07 Feb 2019 21:42:43 -0600 Date: Thu, 7 Feb 2019 21:42:41 -0600 From: "Gustavo A. R. Silva" To: Jiri Pirko , Ido Schimmel , "David S. Miller" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH net-next] mlxsw: spectrum_router: Use struct_size() in kzalloc() Message-ID: <20190208034241.GA11858@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: 1grx3r-001met-8v X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.49.191]:49408 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 29 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 = kzalloc(size, GFP_KERNEL) Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL) Notice that, in this case, variable alloc_size is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- .../net/ethernet/mellanox/mlxsw/spectrum_router.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 230e1f6e192b..e3a3535f9f23 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -3813,13 +3813,11 @@ mlxsw_sp_nexthop4_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi) struct mlxsw_sp_nexthop_group *nh_grp; struct mlxsw_sp_nexthop *nh; struct fib_nh *fib_nh; - size_t alloc_size; int i; int err; - alloc_size = sizeof(*nh_grp) + - fi->fib_nhs * sizeof(struct mlxsw_sp_nexthop); - nh_grp = kzalloc(alloc_size, GFP_KERNEL); + nh_grp = kzalloc(struct_size(nh_grp, nexthops, fi->fib_nhs), + GFP_KERNEL); if (!nh_grp) return ERR_PTR(-ENOMEM); nh_grp->priv = fi; @@ -5045,13 +5043,11 @@ mlxsw_sp_nexthop6_group_create(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_nexthop_group *nh_grp; struct mlxsw_sp_rt6 *mlxsw_sp_rt6; struct mlxsw_sp_nexthop *nh; - size_t alloc_size; int i = 0; int err; - alloc_size = sizeof(*nh_grp) + - fib6_entry->nrt6 * sizeof(struct mlxsw_sp_nexthop); - nh_grp = kzalloc(alloc_size, GFP_KERNEL); + nh_grp = kzalloc(struct_size(nh_grp, nexthops, fib6_entry->nrt6), + GFP_KERNEL); if (!nh_grp) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&nh_grp->fib_list); -- 2.20.1