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 31503C433FF for ; Tue, 6 Aug 2019 00:06:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC8AF214C6 for ; Tue, 6 Aug 2019 00:06:42 +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="rzsiGCpT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731075AbfHFAGl (ORCPT ); Mon, 5 Aug 2019 20:06:41 -0400 Received: from gateway24.websitewelcome.com ([192.185.51.196]:39955 "EHLO gateway24.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728851AbfHFAGl (ORCPT ); Mon, 5 Aug 2019 20:06:41 -0400 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway24.websitewelcome.com (Postfix) with ESMTP id 65C35639712 for ; Mon, 5 Aug 2019 19:06:40 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id umzwheSqf2PzOumzwhiMw8; Mon, 05 Aug 2019 19:06:40 -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=koLpWuT5DW1ydHP7Hd6CN3OPz230NOB+Koz/yZnfNw4=; b=rzsiGCpTfEX6aUerRPFERR6Eux NnT9o7NWvcz9xv1PpufltCUSU8I7MncwqQd82/kDf+NH7aaqLYsBrjxpJ3hoBAHzrytmZH5QGbDyP xZnXPMnBhfAeYhfhNorCNQfOfAJ1fJF/WdA4cT5Ovo5GIp6XxFJwQgb7dg1I+2BUBF596RBqpHl2p 9ByYd0S/ERtvlSjUbfDUJ/frf55oU/G/WvM/XE3qEcRcU4XayIrKdCD++nO2Zmi3ihyVb+EGLE+rU JcUj3cvMqB0uwjMm13I6KfZb1K3Tnn4UwAmsi5+sbX1xV/nFRW7o+Sa6joK2vjyg5Wq5rgMS20l6A YWafolkg==; Received: from [187.192.11.120] (port=40864 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1humzv-00177M-Dt; Mon, 05 Aug 2019 19:06:39 -0500 Date: Mon, 5 Aug 2019 19:06:38 -0500 From: "Gustavo A. R. Silva" To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] Input: applespi - use struct_size() helper Message-ID: <20190806000638.GA4827@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: 187.192.11.120 X-Source-L: No X-Exim-ID: 1humzv-00177M-Dt X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [187.192.11.120]:40864 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 3 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 touchpad_protocol { ... struct tp_finger fingers[0]; }; 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(*tp) + tp->number_of_fingers * sizeof(tp->fingers[0]); with: struct_size(tp, fingers, tp->number_of_fingers) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/input/keyboard/applespi.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/input/keyboard/applespi.c b/drivers/input/keyboard/applespi.c index acf34a5ff571..584289b67fb3 100644 --- a/drivers/input/keyboard/applespi.c +++ b/drivers/input/keyboard/applespi.c @@ -1494,8 +1494,7 @@ static void applespi_got_data(struct applespi_data *applespi) size_t tp_len; tp = &message->touchpad; - tp_len = sizeof(*tp) + - tp->number_of_fingers * sizeof(tp->fingers[0]); + tp_len = struct_size(tp, fingers, tp->number_of_fingers); if (le16_to_cpu(message->length) + 2 != tp_len) { dev_warn_ratelimited(&applespi->spi->dev, -- 2.22.0