P2P: DHCP failure due to EAPOL KEY M4 lost

[Charley Chu]

Hi,

While connecting an Android phone with a P2P device (Group owner), we occasionally
see the DHCP failure. The WPA_SUPPLICANT log messages on Android phone shows the 
WPA 4-WAY handshakes are completed and a DHCP Discover is sent. But the P2P 
device on the other end, doesn't respond to the DHCP Discover, instead it repeats
the EAPOL KEY M3. It appears the P2P device still wait for the EAPOL KEY M4. 
The WireShark capture shows the EAPOL KEY M4 was sent by the Android phone, 
but is not received by the P2P device (no acknowledge from the P2P device). 
We know something wrong with the P2P device (missed the M4 becausing of scanning?), 
but we think WPA_SUPPLICANT should give them a chance to recover from that, e.g:
confirming the M4 is acknowledged before moving to next state. 

I'm new to WPA_SUPPLICANT, could someone here explains to me if/how this situation is 
handled in WPA_SUPPLICANT? Note that the GROUP HANDSHAKE is skipped as the GTK is 
received in pairwise handshake.   

wpa_supplicant version: v2.0-devel-4.1.2  

Thanks in advance,

Charley
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