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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 0DF5EECE561 for ; Mon, 24 Sep 2018 14:25:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE96F21480 for ; Mon, 24 Sep 2018 14:25:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE96F21480 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730721AbeIXU2G (ORCPT ); Mon, 24 Sep 2018 16:28:06 -0400 Received: from mail.bootlin.com ([62.4.15.54]:41708 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728232AbeIXU2G (ORCPT ); Mon, 24 Sep 2018 16:28:06 -0400 Received: by mail.bootlin.com (Postfix, from userid 110) id 07AEE207CA; Mon, 24 Sep 2018 16:25:40 +0200 (CEST) Received: from localhost (242.171.71.37.rev.sfr.net [37.71.171.242]) by mail.bootlin.com (Postfix) with ESMTPSA id CFCEE20725; Mon, 24 Sep 2018 16:25:39 +0200 (CEST) From: Alexandre Belloni To: linux-rtc@vger.kernel.org Cc: Gregory Clement , Thomas Petazzoni , linux-kernel@vger.kernel.org, Alexandre Belloni Subject: [PATCH 1/3] rtc: armada38x: fix possible race condition Date: Mon, 24 Sep 2018 16:25:34 +0200 Message-Id: <20180924142536.27801-1-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.19.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The IRQ is requested before the struct rtc is allocated and registered, but this struct is used in the IRQ handler. This may lead to a NULL pointer dereference. Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc before requesting the IRQ. Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-armada38x.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/rtc/rtc-armada38x.c b/drivers/rtc/rtc-armada38x.c index bde53c8ccee2..b74338d6dde6 100644 --- a/drivers/rtc/rtc-armada38x.c +++ b/drivers/rtc/rtc-armada38x.c @@ -514,7 +514,6 @@ MODULE_DEVICE_TABLE(of, armada38x_rtc_of_match_table); static __init int armada38x_rtc_probe(struct platform_device *pdev) { - const struct rtc_class_ops *ops; struct resource *res; struct armada38x_rtc *rtc; const struct of_device_id *match; @@ -551,6 +550,11 @@ static __init int armada38x_rtc_probe(struct platform_device *pdev) dev_err(&pdev->dev, "no irq\n"); return rtc->irq; } + + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc_dev)) + return PTR_ERR(rtc->rtc_dev); + if (devm_request_irq(&pdev->dev, rtc->irq, armada38x_rtc_alarm_irq, 0, pdev->name, rtc) < 0) { dev_warn(&pdev->dev, "Interrupt not available.\n"); @@ -560,28 +564,24 @@ static __init int armada38x_rtc_probe(struct platform_device *pdev) if (rtc->irq != -1) { device_init_wakeup(&pdev->dev, 1); - ops = &armada38x_rtc_ops; + rtc->rtc_dev->ops = &armada38x_rtc_ops; } else { /* * If there is no interrupt available then we can't * use the alarm */ - ops = &armada38x_rtc_ops_noirq; + rtc->rtc_dev->ops = &armada38x_rtc_ops_noirq; } rtc->data = (struct armada38x_rtc_data *)match->data; - /* Update RTC-MBUS bridge timing parameters */ rtc->data->update_mbus_timing(rtc); - rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name, - ops, THIS_MODULE); - if (IS_ERR(rtc->rtc_dev)) { - ret = PTR_ERR(rtc->rtc_dev); + ret = rtc_register_device(rtc->rtc_dev); + if (ret) dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); - return ret; - } - return 0; + + return ret; } #ifdef CONFIG_PM_SLEEP -- 2.19.0