"handle_beacon - too short payload" messages

[Pavel Roskin]

On 07/23/2011 04:43 PM, Harshal Chhaya wrote:
> I see the following messages from hostapd (I added the 'should be' part):
>
> handle_beacon - too short payload (len=29), should be 36 (24 + 12)
> handle_beacon - too short payload (len=24), should be 36 (24 + 12)
> handle_beacon - too short payload (len=33), should be 36 (24 + 12)
> handle_beacon - too short payload (len=28), should be 36 (24 + 12)
> handle_beacon - too short payload (len=25), should be 36 (24 + 12)
>
> This message is printed every few seconds.
>
> This is with 12 laptop clients (Win7, Macs) connected using WPA2 with
> freeRADIUS as the authenticator. The CPU is 10%-15% loaded. There are
> at least 6-8 other APs on this channel but they are all lightly loaded
> (it's Sat and the office is pretty quiet).
>
> Is this worth investigating further? i.e. could it point to some other problem?

Please post the version of hostapd.  It's always a good idea to provide 
the version of the software that gives you a problem of prints 
unexpected output.  The hostapd config would be useful too, perhaps 
without the passwords.

I guess some of the APs send invalid beacons.  You may want to use 
Wireshark to capture the offending beacons to see what's wrong with them.

len=24 means that there are no fixed parameters in the beacon at all, 
not even the timestamp.

If you don't find broken beacons on the air (on the same channel), then 
the wireless driver becomes suspect.  Then please post the version of 
the kernel, the driver you are using and the name of the wireless device.

-- 
Regards,
Pavel Roskin