-current on BeableBone successful

[John-Mark Gurney]

Tim Kientzle wrote this message on Sun, Sep 09, 2012 at 20:16 -0700:
> > Third is that I get this error:
> > ip length 328 disagrees with bytes received 330.
> > accepting packet with data after udp payload.
> > 
> > This appeard to be from sbin/dhclient/packet.c...  Not sure exactly why
> > we are returning a large packet to userland?
> 
> I haven't seen this one.

Looks like this is a BeagleBone issue.  I haven't tracked it down, but
I did a tcpdump on the server (my other arm board), and the packet has
the correct length of 342 bytes to match the 328 ip length (plus 14
bytes of ethernet header)...  tcpdump on the BeagleBone receives a
344 byte frame with a couple of stray bytes at the end of the frame...

Could this be an miscalculation when we are copying around the frame
to deal the fact our IP stack can't deal w/ misaligned headers?  Just
a thought..

Hmm...  Just ran some experiments... 

ping -s		sent	received
1		0x2b	0x3e
10		0x34	0x3e
18		0x3c	0x3e
19		0x3d	0x3f
20		0x3e	0x40
21		0x3f	0x41
99		0x8d	0x8f
100		0x8e	0x90
101		0x8f	0x91
999		0x411	0x413
1000		0x412	0x414
1001		0x413	0x415

and 0x3e is 62, which is two short of the min frame length of 64...

Hope this helps.

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."