From patchwork Tue Dec 8 01:54:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Changzhong X-Patchwork-Id: 339825 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 B77BBC4361B for ; Tue, 8 Dec 2020 01:52:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77FD42388C for ; Tue, 8 Dec 2020 01:52:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726000AbgLHBvw (ORCPT ); Mon, 7 Dec 2020 20:51:52 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:9031 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725877AbgLHBvv (ORCPT ); Mon, 7 Dec 2020 20:51:51 -0500 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Cqjn70kW3zhp8H; Tue, 8 Dec 2020 09:50:35 +0800 (CST) Received: from compute.localdomain (10.175.112.70) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server (TLS) id 14.3.487.0; Tue, 8 Dec 2020 09:50:56 +0800 From: Zhang Changzhong To: Andy Gross , Bjorn Andersson , Srinivas Kandagatla , Sagar Dharia , "Greg Kroah-Hartman" CC: Zhang Changzhong , , Subject: [PATCH] slimbus: qcom: fix potential NULL dereference in qcom_slim_prg_slew() Date: Tue, 8 Dec 2020 09:54:32 +0800 Message-ID: <1607392473-20610-1-git-send-email-zhangchangzhong@huawei.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 X-Originating-IP: [10.175.112.70] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org platform_get_resource_byname() may fail and in this case a NULL dereference will occur. Fix it to use devm_platform_ioremap_resource_byname() instead of calling platform_get_resource_byname() and devm_ioremap(). 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); Fixes: ad7fcbc308b0 ("slimbus: qcom: Add Qualcomm Slimbus controller driver") Signed-off-by: Zhang Changzhong --- drivers/slimbus/qcom-ctrl.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/slimbus/qcom-ctrl.c b/drivers/slimbus/qcom-ctrl.c index 4aad256..f04b961 100644 --- a/drivers/slimbus/qcom-ctrl.c +++ b/drivers/slimbus/qcom-ctrl.c @@ -472,15 +472,10 @@ static void qcom_slim_rxwq(struct work_struct *work) static void qcom_slim_prg_slew(struct platform_device *pdev, struct qcom_slim_ctrl *ctrl) { - struct resource *slew_mem; - if (!ctrl->slew_reg) { /* SLEW RATE register for this SLIMbus */ - slew_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, - "slew"); - ctrl->slew_reg = devm_ioremap(&pdev->dev, slew_mem->start, - resource_size(slew_mem)); - if (!ctrl->slew_reg) + ctrl->slew_reg = devm_platform_ioremap_resource_byname(pdev, "slew"); + if (IS_ERR(ctrl->slew_reg)) return; }