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NdisAllocateNetBufferAndNetBufferList wrong pool type

kolakola Member Posts: 7

I want to send UDP packet from my filter driver, and use the following code:

NdisZeroMemory(&PoolParameters, sizeof(NET_BUFFER_LIST_POOL_PARAMETERS));

PoolParameters.Header.Type = NDIS_OBJECT_TYPE_DEFAULT;
PoolParameters.ProtocolId = NDIS_PROTOCOL_ID_DEFAULT;
PoolParameters.ContextSize = 0;
PoolParameters.DataSize = 0x100; // My packet size
PoolParameters.fAllocateNetBuffer = TRUE;
PoolParameters.PoolTag = 'KFLT';

NDIS_HANDLE hPoolHandle = NdisAllocateNetBufferListPool(g_NdisFilterDeviceHandle, &PoolParameters);

PNET_BUFFER_LIST pMyNbl = NdisAllocateNetBufferAndNetBufferList(hPoolHandle, 0, 0, NULL, 0, 0);

NdisAllocateNetBufferListPool returns valid handle, but NdisAllocateNetBufferAndNetBufferList returns NULL, and outputs the debug string:

NdisAllocateNetBufferAndNetBufferList: Pool <address> wrong pool type

Can you explain what's wrong?


  • Peter_Viscarola_(OSR)Peter_Viscarola_(OSR) Administrator Posts: 8,240

    I know LESS than nothing about NDIS anymore. But I can read the documentation:

    The fAllocateNetBuffer member of the NET_BUFFER_LIST_POOL_PARAMETERS structure that the caller passed to NdisAllocateNetBufferListPool must have been set to TRUE and the DataSize member set to zero.


    Peter Viscarola

  • kolakola Member Posts: 7

    Good point, but a bit below, opposite thing is written:

    You can also call NdisAllocateNetBufferListPool and set the DataSize member to a nonzero value when creating a NET_BUFFER_LIST structure pool. In this case, a NET_BUFFER structure, MDL, and data are preallocated with each NET_BUFFER_LIST structure that the caller allocates from the pool.

    However, in this case, NdisAllocateNetBufferList should be used, that makes sense, since NET_BUFFER is already pre-allocated by NdisAllocateNetBufferListPool.

    Now it works , thanks again, Peter!

  • Peter_Viscarola_(OSR)Peter_Viscarola_(OSR) Administrator Posts: 8,240

    That’s why I’m here: To work miracles. By reading the MSDN pages. ;-)


    Peter Viscarola

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