From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754449Ab1EGBVp (ORCPT ); Fri, 6 May 2011 21:21:45 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:45175 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754176Ab1EGBVI (ORCPT ); Fri, 6 May 2011 21:21:08 -0400 From: John Stultz To: lkml Cc: John Stultz , Wolfram Sang , Alessandro Zummo , Thomas Gleixner , rtc-linux@googlegroups.com Subject: [PATCH 09/11] rtc: pcap: Initialize drvdata before registering device Date: Fri, 6 May 2011 18:20:52 -0700 Message-Id: <1304731254-3238-10-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 1.7.3.2.146.gca209 In-Reply-To: <1304731254-3238-1-git-send-email-john.stultz@linaro.org> References: <1304731254-3238-1-git-send-email-john.stultz@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the device or platform drvdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the drvdata is initialized prior to registering the rtc device. CC: Wolfram Sang CC: Alessandro Zummo CC: Thomas Gleixner CC: rtc-linux@googlegroups.com Signed-off-by: John Stultz --- drivers/rtc/rtc-pcap.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/drivers/rtc/rtc-pcap.c b/drivers/rtc/rtc-pcap.c index a633abc..cd4f198 100644 --- a/drivers/rtc/rtc-pcap.c +++ b/drivers/rtc/rtc-pcap.c @@ -151,6 +151,8 @@ static int __devinit pcap_rtc_probe(struct platform_device *pdev) pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent); + platform_set_drvdata(pdev, pcap_rtc); + pcap_rtc->rtc = rtc_device_register("pcap", &pdev->dev, &pcap_rtc_ops, THIS_MODULE); if (IS_ERR(pcap_rtc->rtc)) { @@ -158,7 +160,6 @@ static int __devinit pcap_rtc_probe(struct platform_device *pdev) goto fail_rtc; } - platform_set_drvdata(pdev, pcap_rtc); timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ); alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA); @@ -177,6 +178,7 @@ fail_alarm: fail_timer: rtc_device_unregister(pcap_rtc->rtc); fail_rtc: + platform_set_drvdata(pdev, NULL); kfree(pcap_rtc); return err; } -- 1.7.3.2.146.gca209