From 4b3687f9c18156cdb71729fe4e0c3000f7e4d7de Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 6 May 2011 17:30:57 -0700 Subject: [PATCH] rtc: pcap: Initialize drvdata before registering device 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 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/rtc/rtc-pcap.c b/drivers/rtc/rtc-pcap.c index a633abc42896..cd4f198cc2ef 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; } -- 2.39.5