Subject: Re: bug in traceroute mtu-discovery
To: Johan Danielsson <joda@pdc.kth.se>
From: Ignatios Souvatzis <ignatios@cs.uni-bonn.de>
List: tech-net
Date: 06/16/1999 10:34:33
On Tue, Jun 15, 1999 at 09:47:28PM +0200, Johan Danielsson wrote:
> 
> >Submitter-Id:	net
> >Originator:	Johan Danielsson
> >Organization:
> >Confidential:	no
> >Synopsis:	bug in traceroute mtu-discovery
> >Severity:	serious
> >Priority:	high
> >Category:	bin
> >Class:		sw-bug
> >Release:	<NetBSD-current source date>
> >Environment:
> 	<machine, os, target, libraries (multiple lines)>
> System: NetBSD blubb.pdc.kth.se 1.4C NetBSD 1.4C (BLUBB+CARDBUS) #61: Thu Jun 10 11:00:19 PDT 1999 joda@blubb.pdc.kth.se:/usr/misc/src/netbsd/netbsd-current/src/sys/arch/i386/compile/BLUBB+CARDBUS i386
> 
> 
> >Description:
> 
> I've always wondered why I could only get traceroute -P to work with
> some machines. It turns out that traceroute doesn't recalculate the
> UDP data length when it gets a EMSGSIZE from sendto, as can be seen in
> this tcpdump output:

I've tried your patch on a m68k machine, but couldn't get answers either
with or without your patch from a two test targets.

I guessit needs a bit more scrutinizing... a ntoh missing or too much?

	-is