[regression]AP with hostapd 0.7.3 can't receive packets beyond authentication (2.6.36-, rt73usb)

[Lee <lee-in-berlin@web.de>]

Hi everyone,

I noticed a bug (details later) in Linus' git tree, which wasn't there in 
2.6.35.7. So I went on to bisect the bug. 12 compiles and reboots later, I 
could narrow it down to this commit:

# bad: [05318bc905467237d4aa68a701f6e92a2b332218] Merge branch 'master' of 
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6

Unfortunately, I couldn't further bisect down wireless-next, because all three 
commits I picked were unworkable (bringing down an interface caused the kernel 
to oops, which made my test case impossible).

The test case is as follows: I have eth0 and wlan0 (the interface to an 
rt37usb device) in a bridge lan0. I have a properly configured hostapd. When I 
try to connect with a client to my hostapd AP, I can successfully 
authenticate, but all further packets don't reach the interface of the AP.

However, I can see broadcast packets *from* the AP on my client, but not the 
other way round (DHCP requests from client to AP). To make sure the bug was 
not specific to broadcast packets, I manually set an IP on my client and tried 
to ping the AP, but those packets didn't come through, either.

Right now I'm a bit clueless on how to get to the root of this bug, so any 
help is appreciated.

Regards,
Lee