From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] mISDN: hfcsusb: Use struct_size() in kzalloc() Date: Tue, 8 Jan 2019 15:27:05 -0600 Message-ID: <20190108212705.GA8470@embeddedor> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" To: Karsten Keil Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: 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; void *entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, 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); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/isdn/hardware/mISDN/hfcsusb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c b/drivers/isdn/hardware/mISDN/hfcsusb.c index 6d05946b445e..124ff530da82 100644 --- a/drivers/isdn/hardware/mISDN/hfcsusb.c +++ b/drivers/isdn/hardware/mISDN/hfcsusb.c @@ -262,8 +262,7 @@ hfcsusb_ph_info(struct hfcsusb *hw) struct dchannel *dch = &hw->dch; int i; - phi = kzalloc(sizeof(struct ph_info) + - dch->dev.nrbchan * sizeof(struct ph_info_ch), GFP_ATOMIC); + phi = kzalloc(struct_size(phi, bch, dch->dev.nrbchan), GFP_ATOMIC); phi->dch.ch.protocol = hw->protocol; phi->dch.ch.Flags = dch->Flags; phi->dch.state = dch->state; -- 2.20.1 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 40ED3C43387 for ; Tue, 8 Jan 2019 21:48:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0246120827 for ; Tue, 8 Jan 2019 21:48:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729331AbfAHVss (ORCPT ); Tue, 8 Jan 2019 16:48:48 -0500 Received: from gateway20.websitewelcome.com ([192.185.67.41]:17714 "EHLO gateway20.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728573AbfAHVsr (ORCPT ); Tue, 8 Jan 2019 16:48:47 -0500 X-Greylist: delayed 1300 seconds by postgrey-1.27 at vger.kernel.org; Tue, 08 Jan 2019 16:48:47 EST Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway20.websitewelcome.com (Postfix) with ESMTP id CE552400CD35E for ; Tue, 8 Jan 2019 15:27:06 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id gytugVEL0YTGMgytugGdxG; Tue, 08 Jan 2019 15:27:06 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=60012 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1ggytu-000Jge-9N; Tue, 08 Jan 2019 15:27:06 -0600 Date: Tue, 8 Jan 2019 15:27:05 -0600 From: "Gustavo A. R. Silva" To: Karsten Keil Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] mISDN: hfcsusb: Use struct_size() in kzalloc() Message-ID: <20190108212705.GA8470@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: 189.250.130.205 X-Source-L: No X-Exim-ID: 1ggytu-000Jge-9N X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:60012 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 18 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 Message-ID: <20190108212705.s3L5a9J5Annh7P79JRfnVqaZOiCfDQ--89M1b3V3B3o@z> 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; void *entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, 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); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/isdn/hardware/mISDN/hfcsusb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c b/drivers/isdn/hardware/mISDN/hfcsusb.c index 6d05946b445e..124ff530da82 100644 --- a/drivers/isdn/hardware/mISDN/hfcsusb.c +++ b/drivers/isdn/hardware/mISDN/hfcsusb.c @@ -262,8 +262,7 @@ hfcsusb_ph_info(struct hfcsusb *hw) struct dchannel *dch = &hw->dch; int i; - phi = kzalloc(sizeof(struct ph_info) + - dch->dev.nrbchan * sizeof(struct ph_info_ch), GFP_ATOMIC); + phi = kzalloc(struct_size(phi, bch, dch->dev.nrbchan), GFP_ATOMIC); phi->dch.ch.protocol = hw->protocol; phi->dch.ch.Flags = dch->Flags; phi->dch.state = dch->state; -- 2.20.1