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Date:   Mon, 29 Nov 2021 23:02:54 +0100
From:   Florian Westphal <fw@strlen.de>
To:     Eric Garver <eric@garver.life>, Florian Westphal <fw@strlen.de>,
        netfilter-devel@vger.kernel.org, Phil Sutter <phil@nwl.cc>
Subject: Re: [PATCH nf] netfilter: nat: force port remap to prevent shadowing
 well-known ports
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Eric Garver <eric@garver.life> wrote:
> On Mon, Nov 29, 2021 at 03:42:18PM +0100, Florian Westphal wrote:
> > If destination port is above 32k and source port below 16k
> > assume this might cause 'port shadowing' where a 'new' inbound
> > connection matches an existing one, e.g.
> 
> How did you arrive at 16k?

I had to pick some number.  1k is too low since some administrative
portals (or openvpn for that matter) are on ports above that.

I wanted to pick something that would not kick in for most cases.
16k just seemed like a good compromise, thats all.