From: Arne Schwabe <arne@...1227...>
References: <C0618847-3DAF-4E68-8143-A0BECC5DFD40@...277...>
Message-ID: <66ae9cc3-cabf-f70d-b4f1-ecfbbf78b6d5@...1227...>
Date: Mon, 8 May 2017 14:54:22 +0200
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In-Reply-To: <C0618847-3DAF-4E68-8143-A0BECC5DFD40@...277...>
Subject: Re: [Openvpn-devel] Fix for OpenVPN MTU Tunnel computation bug for
 TLS reconnects
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To: Dirkjan Bussink <d.bussink@...277...>, "openvpn-devel@lists.sourceforge.net" <openvpn-devel@lists.sourceforge.net>

Am 05.05.17 um 13:38 schrieb Dirkjan Bussink:
> 
> When testing upgrading OpenVPN from 2.3 to 2.4, we ran into an issue where
> every time the same client reconnects the MTU for the tunnel used shrinks,
> eventually leading to packets being dropped by OpenVPN.
> 
> Reproduced the problem with a 2 node setup, one as the server and the other
> one as a client. Each time the client is restarted the packet sizes shrink
> until it breaks. 
> 

I can reproduce this problem. Actually I have experienced that problem
longer but never looked into enough. On first glance it looks okay and
the patch actually also works for me but I don't know the reuse code
path good enough to figure what is really going on.

I am actually suprised that this is "TLS resuse" as in my case the
client is completely restarted.

Arne