openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

rtc: rp5c01: Initialize drvdata before registering device 

Commit f44f7f96a2 ("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 <w.sang@pengutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
John Stultz 2011-05-06 17:31:20 -07:00
parent 4b3687f9c1
commit 130107b270
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/rtc/rtc-rp5c01.c
View File

@ -249,15 +249,15 @@ static int __init rp5c01_rtc_probe(struct platform_device *dev)
spin_lock_init(&priv->lock); spin_lock_init(&priv->lock);
platform_set_drvdata(dev, priv);
rtc = rtc_device_register("rtc-rp5c01", &dev->dev, &rp5c01_rtc_ops, rtc = rtc_device_register("rtc-rp5c01", &dev->dev, &rp5c01_rtc_ops,
THIS_MODULE); THIS_MODULE);
if (IS_ERR(rtc)) { if (IS_ERR(rtc)) {
error = PTR_ERR(rtc); error = PTR_ERR(rtc);
goto out_unmap; goto out_unmap;
} }
priv->rtc = rtc; priv->rtc = rtc;
platform_set_drvdata(dev, priv);
error = sysfs_create_bin_file(&dev->dev.kobj, &priv->nvram_attr); error = sysfs_create_bin_file(&dev->dev.kobj, &priv->nvram_attr);
if (error) if (error)
@ -268,6 +268,7 @@ static int __init rp5c01_rtc_probe(struct platform_device *dev)
out_unregister: out_unregister:
rtc_device_unregister(rtc); rtc_device_unregister(rtc);
out_unmap: out_unmap:
platform_set_drvdata(dev, NULL);
iounmap(priv->regs); iounmap(priv->regs);
out_free_priv: out_free_priv:
kfree(priv); kfree(priv);