misc/178379: [net80211] [ath] WPA rekey on the STA side fails when transmitting lots of UDP traffic

[adrian chadd]

>Number:         178379
>Category:       misc
>Synopsis:       [net80211] [ath] WPA rekey on the STA side fails when transmitting lots of UDP traffic
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon May 06 22:10:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     adrian chadd
>Release:        
>Organization:
>Environment:
>Description:
When UDP iperf transmit is going on, a WPA group rekey fails and the AP ditches the station.

What's going on:

* FreeBSD AP -> FreeBSD STA (both ath)
* AP sends a WPA rekey EAPOL message to the STA
* STA updates the key, sends an EAPOL message back
* AP doesn't get it, so it eventually disconnects the station.

What's breaking:

* The STA gets the EAPOL group rekey frame
* the STA updates the keycache entry
* The STA sends the EAPOL response
* .. but it doesn't actually send the frame, it gets dropped by ath_start() because the buffers are all allocated.

I'll dig into it some more.
>How-To-Repeat:

>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: