[NTOSKRNL]

- Check that the caller passed a valid PDO pointer to IoOpenDeviceRegistryKey

svn path=/trunk/; revision=47827

reactos/ntoskrnl/io/pnpmgr/pnpmgr.c

@@ -3528,6 +3528,8 @@ IoOpenDeviceRegistryKey(IN PDEVICE_OBJECT DeviceObject,
    else
    {
       DeviceNode = IopGetDeviceNode(DeviceObject);
+      if (!DeviceNode)
+          return STATUS_INVALID_DEVICE_REQUEST;
       KeyNameLength += sizeof(EnumKeyName) - sizeof(UNICODE_NULL) +
                        DeviceNode->InstancePath.Length;
    }