A protocol driver may receive packets from NDIS even though the driver has its packet filters set to zero to disable packet reception

Support

Hello,

Select a different account.

You have multiple accounts

Choose the account you want to sign in with.

Applies To

Windows Driver Kit 7.0

Symptom

NDIS is indicating received data to any protocol drivers bound to a wireless miniport device even though the packet filter of a protocol driver is set to 0, i.e. disable packet reception by the protocol driver. Problem can be reproduced with the WDK NDIS protocol sample (ndisprot).

Cause

Before NDIS indicates a packet to the protocol driver, NDIS will do the check for a zero packet filter (which is the default for protocol driver) only if the media type is 802.3 or 802.5 (Ethernet or Token ring). For other media types (such as native wifi), NDIS won’t do the check for the protocol packet filter value and will indicate packets (that were indicated from the underlying miniport) unconditionally to the protocol driver.

Resolution

The protocol driver needs to handle this situation by expecting that NDIS may call its ProtocolReceiveNetBufferLists function when indicating packets received from the miniport even though the protocol driver packet filter was set to zero.