From 2f5c4fe8f9811152d69ef5cd020e095a1f84ca65 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 6 May 2011 17:26:25 -0700 Subject: [PATCH] rtc: max8925: 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-max8925.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c index 20494b5e..3bc046f 100644 --- a/drivers/rtc/rtc-max8925.c +++ b/drivers/rtc/rtc-max8925.c @@ -258,6 +258,8 @@ static int __devinit max8925_rtc_probe(struct platform_device *pdev) } dev_set_drvdata(&pdev->dev, info); + /* XXX - isn't this redundant? */ + platform_set_drvdata(pdev, info); info->rtc_dev = rtc_device_register("max8925-rtc", &pdev->dev, &max8925_rtc_ops, THIS_MODULE); @@ -267,10 +269,9 @@ static int __devinit max8925_rtc_probe(struct platform_device *pdev) goto out_rtc; } - platform_set_drvdata(pdev, info); - return 0; out_rtc: + platform_set_drvdata(pdev, NULL); free_irq(chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info); out_irq: kfree(info); -- 2.7.4