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,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 35684C282C2 for ; Fri, 8 Feb 2019 00:28:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 005132073F for ; Fri, 8 Feb 2019 00:28:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726832AbfBHA2U (ORCPT ); Thu, 7 Feb 2019 19:28:20 -0500 Received: from gateway34.websitewelcome.com ([192.185.148.200]:19284 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726758AbfBHA2U (ORCPT ); Thu, 7 Feb 2019 19:28:20 -0500 Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway34.websitewelcome.com (Postfix) with ESMTP id 5ABC557F1F6 for ; Thu, 7 Feb 2019 18:28:19 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id ru1jgMGLpdnCeru1jgMKFA; Thu, 07 Feb 2019 18:28:19 -0600 X-Authority-Reason: nr=8 Received: from [189.250.49.191] (port=46210 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gru1i-003sDb-L5; Thu, 07 Feb 2019 18:28:18 -0600 Date: Thu, 7 Feb 2019 18:28:17 -0600 From: "Gustavo A. R. Silva" To: Marcel Holtmann , Johan Hedberg , "David S. Miller" Cc: linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] Bluetooth: a2mp: Use struct_size() helper Message-ID: <20190208002817.GA15338@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: 1gru1i-003sDb-L5 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.49.191]:46210 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 4 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@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 = alloc(size, GFP_KERNEL) Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: size = struct_size(instance, entry, count); instance = alloc(size, GFP_KERNEL) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- net/bluetooth/a2mp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c index 58fc6333d412..5f918ea18b5a 100644 --- a/net/bluetooth/a2mp.c +++ b/net/bluetooth/a2mp.c @@ -174,7 +174,7 @@ static int a2mp_discover_req(struct amp_mgr *mgr, struct sk_buff *skb, num_ctrl++; } - len = num_ctrl * sizeof(struct a2mp_cl) + sizeof(*rsp); + len = struct_size(rsp, cl, num_ctrl); rsp = kmalloc(len, GFP_ATOMIC); if (!rsp) { read_unlock(&hci_dev_list_lock); -- 2.20.1