thermal: bcm2835: Fix crash in bcm2835_thermal_debugfs

"cat /sys/kernel/debug/bcm2835_thermal/regset" causes a NULL pointer
dereference in bcm2835_thermal_debugfs. The driver makes use of the
implementation details of the thermal framework to retrieve a pointer
to its private data from a struct thermal_zone_device, and gets it
wrong - leading to the crash. Instead, store its private data as the
drvdata and retrieve the thermal_zone_device pointer from it.

Fixes: bcb7dd9ef2 ("thermal: bcm2835: add thermal driver for bcm2835 SoC")

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This commit is contained in:
Phil Elwell 2019-01-29 09:55:57 +00:00 committed by Zhang Rui
parent 3b5236cc5d
commit 35122495a8

View File

@ -119,8 +119,7 @@ static const struct debugfs_reg32 bcm2835_thermal_regs[] = {
static void bcm2835_thermal_debugfs(struct platform_device *pdev)
{
struct thermal_zone_device *tz = platform_get_drvdata(pdev);
struct bcm2835_thermal_data *data = tz->devdata;
struct bcm2835_thermal_data *data = platform_get_drvdata(pdev);
struct debugfs_regset32 *regset;
data->debugfsdir = debugfs_create_dir("bcm2835_thermal", NULL);
@ -266,7 +265,7 @@ static int bcm2835_thermal_probe(struct platform_device *pdev)
data->tz = tz;
platform_set_drvdata(pdev, tz);
platform_set_drvdata(pdev, data);
/*
* Thermal_zone doesn't enable hwmon as default,
@ -290,8 +289,8 @@ err_clk:
static int bcm2835_thermal_remove(struct platform_device *pdev)
{
struct thermal_zone_device *tz = platform_get_drvdata(pdev);
struct bcm2835_thermal_data *data = tz->devdata;
struct bcm2835_thermal_data *data = platform_get_drvdata(pdev);
struct thermal_zone_device *tz = data->tz;
debugfs_remove_recursive(data->debugfsdir);
thermal_zone_of_sensor_unregister(&pdev->dev, tz);