Access point stops responding after several hours

[Rob Browning]

I have an access point that's running a very recent compat-wireless (a
few days old), kernel 2.6.30-2-686 (Debian), and a build of hostapd as
of 2009-10-17 (08d38568).  The machine also has an AR5008 (ath9k) based
PCI card.

After the machine reboots, wireless clients are able to connect to the
AP for quite a while.  However, after some number of hours (perhaps
about 6-9), all connections fail, and hostapd no longer responds.  After
that the clients can't see the network at all, and hostapd no longer
prints messages to the log when clients try to connect.

Once this has happened, if I restart hostapd with -dd, it doesn't print
anything after this:

  WPA: group state machine entering state GTK_INIT (VLAN-ID 0)
  GMK - hexdump(len=32): [REMOVED]
  GTK - hexdump(len=32): [REMOVED]
  WPA: group state machine entering state SETKEYSDONE (VLAN-ID 0)
  nl_set_encr: ifindex=5 alg=2 addr=(nil) key_idx=1 set_tx=1 seq_len=0 key_len=32
  nl80211: Set beacon (beacon_set=0)
  wlan0: Setup of interface done.
  MGMT (TX callback) ACK

Eventually, it does print some blocks like this:

  wlan0: WPA rekeying GTK
  WPA: group state machine entering state SETKEYS (VLAN-ID 0)
  GMK - hexdump(len=32): [REMOVED]
  GTK - hexdump(len=32): [REMOVED]
  wpa_group_setkeys: GKeyDoneStations=0
  WPA: group state machine entering state SETKEYSDONE (VLAN-ID 0)
  nl_set_encr: ifindex=5 alg=2 addr=(nil) key_idx=2 set_tx=1 seq_len=0 key_len=32
  wlan0: WPA rekeying GTK

but no clients can connect.

Assuming this isn't a local configuration problem, I'd like to help fix
this if I can.  In case it matters, the machine in question does have a
bridge (that doesn't involve the wireless interface), and is also
running shorewall.

Please let me know if I can provide further information.

Thanks
-- 
Rob Browning
rlb @defaultvalue.org and @debian.org; previously @cs.utexas.edu
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