From owner-freebsd-hackers  Sat Mar  2 12:23:54 2002
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Date: Sat, 2 Mar 2002 12:23:50 -0800
From: Luigi Rizzo <rizzo@icir.org>
To: "Crist J. Clark" <cjc@FreeBSD.ORG>
Cc: Leo Bicknell <bicknell@ufp.org>, Bob Bishop <rb@gid.co.uk>,
	"George V. Neville-Neil" <gnn@neville-neil.com>,
	Doug Ambrisko <ambrisko@ambrisko.com>, hackers@FreeBSD.ORG
Subject: Re: Multicast problem with sis interface?
Message-ID: <20020302122350.A49121@iguana.icir.org>
References: <200203010557.VAA1802420@meer.meer.net> <rb@gid.co.uk> <4.3.2.7.2.20020222165515.00c14850@gid.co.uk> <200203010557.VAA1802420@meer.meer.net> <4.3.2.7.2.20020301112956.00c5b550@gid.co.uk> <20020301035623.A32974@iguana.icir.org> <20020301184123.GA5908@ussenterprise.ufp.org> <20020302121233.G66092@blossom.cjclark.org>
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On Sat, Mar 02, 2002 at 12:12:33PM -0800, Crist J. Clark wrote:
> > > ok, these three drivers behave as follows:
...
> > >  "ed" pads with whatever is left in the transmit buffer from
> > >       earlier transmissions;
> > >  "vr" pads with whatever is available in the mbuf after the actual data;
> > 
> > I point out both of these are security risks.  Granted, fairly
> > minor, but they allow someone to get all/part of a previous packet's
> > data, when they should have it.  This sort of thing has been used
...
> The only "people" who can see the leftover stuff are the same ones who
> could have seen the original packet (the exception being very simple

not in the "vr" case, because the junk comes from the mbuf. Which
could have stored something else in the past, not just a packet previously
gone out on the same interface.

	cheers
	luigi

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