platform/x86: intel_menlow: avoid null pointer deference error

Fix a null pointer deference by acpi_driver_data() if device is
null (dereference before check). We should only set cdev and check
this is OK after we are sure device is not null.

Signed-off-by: Young Xiao <92siuyang@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

diff --git a/drivers/platform/x86/intel_menlow.c b/drivers/platform/x86/intel_menlow.c
index 77eb870..b102f6d 100644 (file)
--- a/drivers/platform/x86/intel_menlow.c
+++ b/drivers/platform/x86/intel_menlow.c
@@ -180,9 +180,13 @@ static int intel_menlow_memory_add(struct acpi_device *device)
 
 static int intel_menlow_memory_remove(struct acpi_device *device)
 {
-       struct thermal_cooling_device *cdev = acpi_driver_data(device);
+       struct thermal_cooling_device *cdev;
+
+       if (!device)
+               return -EINVAL;
 
-       if (!device || !cdev)
+       cdev = acpi_driver_data(device);
+       if (!cdev)
                return -EINVAL;
 
        sysfs_remove_link(&device->dev.kobj, "thermal_cooling");