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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E4DBC433F5 for ; Mon, 16 May 2022 14:01:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244162AbiEPOBt (ORCPT ); Mon, 16 May 2022 10:01:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244177AbiEPOBp (ORCPT ); Mon, 16 May 2022 10:01:45 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E553A3A18D; Mon, 16 May 2022 07:01:44 -0700 (PDT) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4L219z6HLMzhZV3; Mon, 16 May 2022 22:00:55 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 16 May 2022 22:01:42 +0800 Received: from [10.174.178.174] (10.174.178.174) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 16 May 2022 22:01:42 +0800 Subject: Re: [PATCH 4.9/4.14/4.19/5.4] tty/serial: digicolor: fix possible null-ptr-deref in digicolor_uart_probe() From: Yang Yingliang To: , CC: , References: <20220516141053.1549344-1-yangyingliang@huawei.com> Message-ID: <3580ada7-3ad8-2caa-8af2-32896b752f2f@huawei.com> Date: Mon, 16 May 2022 22:01:41 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20220516141053.1549344-1-yangyingliang@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.174.178.174] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I use a wrong commit id, please ignore this patch. On 2022/5/16 22:10, Yang Yingliang wrote: > commit 7c25a0b89a487878b0691e6524fb5a8827322194 upstream. > > It will cause null-ptr-deref when using 'res', if platform_get_resource() > returns NULL, so move using 'res' after devm_ioremap_resource() that > will check it to avoid null-ptr-deref. > And use devm_platform_get_and_ioremap_resource() to simplify code. > > Fixes: 5930cb3511df ("serial: driver for Conexant Digicolor USART") > Signed-off-by: Yang Yingliang > Reviewed-by: Baruch Siach > Cc: stable > Link: https://lore.kernel.org/r/20220505124621.1592697-1-yangyingliang@huawei.com > Signed-off-by: Greg Kroah-Hartman > --- > v1: > These stable versions don't have devm_platform_get_and_ioremap_resource(), > so just move using 'res' after devm_ioremap_resource(). > --- > drivers/tty/serial/digicolor-usart.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c > index 50ec5f1ac77f4..794864fac6250 100644 > --- a/drivers/tty/serial/digicolor-usart.c > +++ b/drivers/tty/serial/digicolor-usart.c > @@ -476,10 +476,10 @@ static int digicolor_uart_probe(struct platform_device *pdev) > return PTR_ERR(uart_clk); > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > - dp->port.mapbase = res->start; > dp->port.membase = devm_ioremap_resource(&pdev->dev, res); > if (IS_ERR(dp->port.membase)) > return PTR_ERR(dp->port.membase); > + dp->port.mapbase = res->start; > > irq = platform_get_irq(pdev, 0); > if (irq < 0)