Filter driver + Bluescreen

Hi schonwieder ,
ich möchte einen Filtertreiber schreiben, welcher Udp Pakete verändert. Ich wollte das so machen das so:

#define DO(s) {DbgPrint(s);}

PDEVICE_OBJECT pUDPObject=NULL;
PDEVICE_OBJECT pOldUDPObject=NULL;

NTSTATUS Entry(PDRIVER_OBJECT pDriverObject, PUNICODE_STRING pRegistryPath)
{
    DO("Entry begin...");

	for (int iFunction = 0; iFunction<IRP_MJ_MAXIMUM_FUNCTION; iFunction++)
		pDriverObject->MajorFunction[iFunction] = Dispatch;
	pDriverObject->DriverUnload=Unload; 

	NTSTATUS Return = IoCreateDevice(pDriverObject,
							0,
							NULL,
							FILE_DEVICE_UNKNOWN,
							0,
							TRUE,
							&pUDPObject);
	if (Return != STATUS_SUCCESS)
	{
		DOERR;
		return Return;
	}
	pUDPObject->Flags |= DO_DIRECT_IO;

	UNICODE_STRING UDPDeviceName;
	RtlInitUnicodeString(&UDPDeviceName, L"\\Device\\Tcp"); //Hier zum Test erstmal TCP
	Return = IoAttachDevice(pUDPObject, &UDPDeviceName, &pOldUDPObject);
	if (Return != STATUS_SUCCESS)
	{
		IoDeleteDevice(pUDPObject);
		DOERR;
		return Return;
	}

    DO("Entry end");

	return Return;
}

typedef struct _EXAMPLE_FILTER_EXTENSION
{
    PDEVICE_OBJECT pNextDeviceInChain;

} EXAMPLE_FILTER_EXTENSION, *PEXAMPLE_FILTER_EXTENSION; // Aus tutorial

NTSTATUS Dispatch(PDEVICE_OBJECT pDeviceObject,PIRP pIRP)
{
	DO("Dispatch begin...");

	NTSTATUS NtStatus = STATUS_NOT_SUPPORTED;
    PEXAMPLE_FILTER_EXTENSION pExampleFilterDeviceContext = (PEXAMPLE_FILTER_EXTENSION)pDeviceObject->DeviceExtension;
    DbgPrint("ExampleFilter_UnSupportedFunction Called \r\n");
    IoSkipCurrentIrpStackLocation(pIRP);
	IoCallDriver(pExampleFilterDeviceContext->pNextDeviceInChain, pIRP);

	DO("Dispatch end...");

    return NtStatus;
}

leider bekomme ich direkt nach dem Laden des Treibers einen Bluescreen und der Rechner fährt sich selber herunter. Wenn ich nun die Dispatch-Funktion durch diese ersetzte, gibt es keinen Bluescreen...

NTSTATUS Dispatch(PDEVICE_OBJECT pDeviceObject,PIRP pIRP)
{
	DO("Dispatch begin...");

	if (!pIRP)
	{
		DOWARNING;
		return STATUS_SUCCESS;
	}

	SCompletion Completion;
	memset(&Completion, NULL, sizeof(SCompletion));

	PIO_STACK_LOCATION pIoStackIrp=IoGetCurrentIrpStackLocation(pIRP);
	switch (pIoStackIrp->MajorFunction)
	{
		case IRP_MJ_CREATE:
			DO("IRP_MJ_CREATE");

			iNumDevicesCreated++;
			break;

		case IRP_MJ_DEVICE_CONTROL:
			DO("IRP_MJ_DEVICE_CONTROL");
			break;

		case IRP_MJ_INTERNAL_DEVICE_CONTROL:
			DO("IRP_MJ_INTERNAL_DEVICE_CONTROL");
			break;

		case IRP_MJ_CLEANUP:
			DO("IRP_MJ_CLEANUP");
			break;

		case IRP_MJ_CLOSE:
			DO("IRP_MJ_CLOSE");

			if(iNumDevicesCreated)
				iNumDevicesCreated--;
			break;

		default:
			DO("default");
			break;
	}

	NTSTATUS Return;
	pIRP->IoStatus.Status = STATUS_SUCCESS;
	Return=STATUS_SUCCESS;

	IoCompleteRequest(pIRP, IO_NO_INCREMENT);

	DO("Dispatch end");

	return Return;
}

Irgendwie blicke ich diese ganze Treiberprogrammierung nicht
Kennt wer vllt. ein gutes Buch für mich?

Die erste DDispatch-Funktion muss natürlich heißen:

NTSTATUS Dispatch(PDEVICE_OBJECT pDeviceObject,PIRP pIRP)
{
    DO("Dispatch begin...");

IoSkipCurrentIrpStackLocation(pIRP);
	return IoCallDriver(pOriginalUdpDevice, pIRP);
}

Aus irgendeinem Grund klappt das jetzt?!