Where Do I Store My Own Device-Specific Data?

At initialization of BFF, if you provide the callback function, DeviceAdd, for creation of bus filter device objects, DeviceAdd, when invoked, will receive two WDF object handles:

1. One is a WDF device object handle which is associated with the parent device object, i.e., the upper filter device object.
2. The other is a WDF general object handle which is associated with a newly created bus filter device object.

Therefore, you may call WdfObjectAllocateContext to allocate your own context space and store your own private data therein.