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re: [ntfsd] Exhausting NonPagedPool

OSR_Community_User-35OSR_Community_User-35 Member Posts: 154
Way back, last year, the following was posted. This may be
contributing to your observed leak.

-----Original Message-----
From: Eliyas Yakub [mailto:[email protected]]
Sent: Thursday, July 29, 1999 11:15 AM
To: 'Steve Hayward'
Cc: '[email protected]'
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.


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.


-----Original Message-----
From: Steve Hayward [mailto:[email protected]]
Sent: Thursday, July 29, 1999 2:51 AM
To: Eliyas Yakub
Subject: RE: [ntdev] IoCreateDevice/IoDeleteDevice memory leak


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

// now delete the device

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

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