From: Eliyas Yakub [eliyasy@microsoft.com]
Sent: Thursday, July 29, 1999 2:15 PM
To: 'Steve Hayward'
Cc: 'ntdev@atria.com'
Subject: RE: [ntdev] IoCreateDevice/IoDeleteDevice memory leak

Yes it's a bug. It will be fixed in the post Win2K release. This memory leak
will happen only if you specify one of the following as your device type.

FILE_DEVICE_DISK 
FILE_DEVICE_TAPE 
FILE_DEVICE_CD_ROM 
FILE_DEVICE_VIRTUAL_DISK

These values are specified only by storage devices,  and at least on NT4.0,
once created these device objects are not deleted at all. Anyway thanks for
your feedback.

Eliyas

-----Original Message-----
From: Steve Hayward [mailto:shayward@avantis.co.uk]
Sent: Thursday, July 29, 1999 2:51 AM
To: Eliyas Yakub
Subject: RE: [ntdev] IoCreateDevice/IoDeleteDevice memory leak


Eliyas

Thanks for your response I have found now the leak.
It seems that the IoDeleteDevice does not free the the VPB block. The
following code plugs the leak.

		// extract the pointer to the Vpb
		pVpb = pNewDeviceObject->Vpb;

		// first free the VPB if it exits
		if(pVpb != NULL)
		{
			// set value in the device object to NULL
			pNewDeviceObject->Vpb = NULL;
		
			// now free the buffer
			ExFreePool(pVpb);
		}

		// now delete the device
		IoDeleteDevice(pNewDeviceObject);

This is also backed up by the fact that creating devices as
FILE_DEVICE_UNKNOWN does not have the same leak problem. 

Steve
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