[PATCH] intel_menlow: prevent NULL pointer dereference

["Vincent Stehlé" <vincent.stehle@intel.com>]

The function acpi_driver_data() will dereference its parameter; make sure
to check for NULL pointer before we call it.

Signed-off-by: Vincent Stehlé <vincent.stehle@intel.com>
Cc: Sujith Thomas <sujith.thomas@intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <len.brown@intel.com>
---
 drivers/platform/x86/intel_menlow.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/intel_menlow.c b/drivers/platform/x86/intel_menlow.c
index 0a919d8..185a1bd 100644
--- a/drivers/platform/x86/intel_menlow.c
+++ b/drivers/platform/x86/intel_menlow.c
@@ -196,9 +196,13 @@ 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");
-- 
2.8.1