From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: BUG: NIU driver: strange issues with multicast "UDP: short
 packet"
Date: Wed, 04 Feb 2009 01:34:31 -0800 (PST)
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From: Jesper Dangaard Brouer <jdb@comx.dk>
Date: Wed, 04 Feb 2009 10:32:06 +0100

> On Wed, 2009-02-04 at 01:00 -0800, David Miller wrote:
> > At the point when IPMR is dealing with potentially forwarding
> > the frame, the UDP headers aren't yet pulled into the linear
> > area.  UDP input will do that with it's pskb_may_pull() call.
> 
> Can I get a little code hint, where IPMR is dealing with potentially
> forwarding the frame?

ip_mr_forward().

> Is there an easy way to test if the packet is corrupted?
> Can you recomment a way to test it?

If UDP header length field is > 2000, you've got a problem.