ACPI / fan: avoid null pointer deference error
Fix a null pointer deference by acpi_driver_data() if device is
null. We should only set cdev and check this is OK after we are
sure device is not null.
Smatch analysis:
drivers/acpi/fan.c:179 acpi_fan_remove() warn: variable dereferenced
before check 'device' (see line 177)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index f815da8..8d1c010 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -174,9 +174,13 @@
static int acpi_fan_remove(struct acpi_device *device)
{
- struct thermal_cooling_device *cdev = acpi_driver_data(device);
+ struct thermal_cooling_device *cdev;
- if (!device || !cdev)
+ if (!device)
+ return -EINVAL;
+
+ cdev = acpi_driver_data(device);
+ if (!cdev)
return -EINVAL;
sysfs_remove_link(&device->dev.kobj, "thermal_cooling");