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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 ACFFFC83000 for ; Tue, 28 Apr 2020 16:16:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 864852054F for ; Tue, 28 Apr 2020 16:16:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="o8Q1dKAK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728587AbgD1QQR (ORCPT ); Tue, 28 Apr 2020 12:16:17 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:56744 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728340AbgD1QQR (ORCPT ); Tue, 28 Apr 2020 12:16:17 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id 03SGFudR001305; Tue, 28 Apr 2020 11:15:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1588090556; bh=8fXivnlbbbn4L5jCdnMcunsvQltul4JatC/I2sDPy3k=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=o8Q1dKAKumI9AuZuygJqiQhmee1QA49Ouc81U59hsiww7bK01VgxgrCqdNp7yzX0e R1MmG05B4DFE+VsTxTkArUSJkdZBttmag33or25f9RZ/vacup2HQj3wS8sL6iOXivO 8R+19OS0oDS3UMBSbIjtaSdyKcwzFlOxoiKTE4cI= Received: from DLEE107.ent.ti.com (dlee107.ent.ti.com [157.170.170.37]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 03SGFuw7008647 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 28 Apr 2020 11:15:56 -0500 Received: from DLEE112.ent.ti.com (157.170.170.23) by DLEE107.ent.ti.com (157.170.170.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Tue, 28 Apr 2020 11:15:56 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DLEE112.ent.ti.com (157.170.170.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Tue, 28 Apr 2020 11:15:56 -0500 Received: from [10.250.234.195] (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 03SGFpMO006509; Tue, 28 Apr 2020 11:15:52 -0500 Subject: Re: [PATCH -next] PCI: dwc: pci-dra7xx: Fix potential NULL dereference in dra7xx_pcie_probe() To: Dan Carpenter CC: Wei Yongjun , Kishon Vijay Abraham I , Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas , , , References: <20200427111044.162618-1-weiyongjun1@huawei.com> <20200428130734.GF2014@kadam> From: Vignesh Raghavendra Message-ID: Date: Tue, 28 Apr 2020 21:45:51 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200428130734.GF2014@kadam> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 28/04/20 6:37 pm, Dan Carpenter wrote: > On Mon, Apr 27, 2020 at 05:29:50PM +0530, Vignesh Raghavendra wrote: >> Hi, >> >> On 27/04/20 4:40 pm, Wei Yongjun wrote: >>> platform_get_resource() may fail and return NULL, so we should >>> better check it's return value to avoid a NULL pointer dereference >>> a bit later in the code. >>> >>> This is detected by Coccinelle semantic patch. >>> >>> @@ >>> expression pdev, res, n, t, e, e1, e2; >>> @@ >>> >>> res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t, n); >>> + if (!res) >>> + return -EINVAL; >>> ... when != res == NULL >>> e = devm_ioremap(e1, res->start, e2); >>> >>> Signed-off-by: Wei Yongjun >>> --- >>> drivers/pci/controller/dwc/pci-dra7xx.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c >>> index 3b0e58f2de58..7a3d12f7e7d9 100644 >>> --- a/drivers/pci/controller/dwc/pci-dra7xx.c >>> +++ b/drivers/pci/controller/dwc/pci-dra7xx.c >>> @@ -878,6 +878,9 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev) >>> } >>> >>> res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf"); > ^^^^ > >>> + if (!res) >>> + return -EINVAL; >>> + >>> base = devm_ioremap(dev, res->start, resource_size(res)); > ^^^ >> >> I don't see why this should be devm_ioremap(). It should also have been >> devm_ioremap_resource() which does the NULL check. > > It's different device pointers. > Sorry, I don't understand this comment... Currently we have: static int __init dra7xx_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; ... res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf"); base = devm_ioremap(dev, res->start, resource_size(res)); if (!base) return -ENOMEM; Instead of the proposed patch, what I am asking is: base = devm_platform_ioremap_resource_byname(pdev, "ti_conf"); if (IS_ERR(base)) return PTR_ERR(base); > regards, > dan carpenter >