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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 5B5DAC76192 for ; Tue, 16 Jul 2019 07:28:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E67E206C2 for ; Tue, 16 Jul 2019 07:28:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729467AbfGPH2N (ORCPT ); Tue, 16 Jul 2019 03:28:13 -0400 Received: from inva020.nxp.com ([92.121.34.13]:51142 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726463AbfGPH2N (ORCPT ); Tue, 16 Jul 2019 03:28:13 -0400 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id D2C5F1A0007; Tue, 16 Jul 2019 09:28:11 +0200 (CEST) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id D12D81A00F6; Tue, 16 Jul 2019 09:28:08 +0200 (CEST) Received: from titan.ap.freescale.net (TITAN.ap.freescale.net [10.192.208.233]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id C2A4240293; Tue, 16 Jul 2019 15:28:04 +0800 (SGT) From: Anson.Huang@nxp.com To: a.zummo@towertech.it, alexandre.belloni@bootlin.com, linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Linux-imx@nxp.com Subject: [PATCH] rtc: snvs: fix possible race condition Date: Tue, 16 Jul 2019 15:18:58 +0800 Message-Id: <20190716071858.36750-1-Anson.Huang@nxp.com> X-Mailer: git-send-email 2.9.5 X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Anson Huang The RTC IRQ is requested before the struct rtc_device is allocated, this may lead to a NULL pointer dereference in IRQ handler. To fix this issue, allocating the rtc_device struct before requesting the RTC IRQ using devm_rtc_allocate_device, and use rtc_register_device to register the RTC device. Signed-off-by: Anson Huang --- drivers/rtc/rtc-snvs.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c index 7ee673a2..4f9a107 100644 --- a/drivers/rtc/rtc-snvs.c +++ b/drivers/rtc/rtc-snvs.c @@ -279,6 +279,10 @@ static int snvs_rtc_probe(struct platform_device *pdev) if (!data) return -ENOMEM; + data->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(data->rtc)) + return PTR_ERR(data->rtc); + data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap"); if (IS_ERR(data->regmap)) { @@ -343,10 +347,9 @@ static int snvs_rtc_probe(struct platform_device *pdev) goto error_rtc_device_register; } - data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, - &snvs_rtc_ops, THIS_MODULE); - if (IS_ERR(data->rtc)) { - ret = PTR_ERR(data->rtc); + data->rtc->ops = &snvs_rtc_ops; + ret = rtc_register_device(data->rtc); + if (ret) { dev_err(&pdev->dev, "failed to register rtc: %d\n", ret); goto error_rtc_device_register; } -- 2.7.4