From mboxrd@z Thu Jan  1 00:00:00 1970
From: Francesco Ruggeri <fruggeri@arista.com>
Subject: Re: [PATCH 1/1] net-next: do not store needed_headroom in ip_tunnel_xmit
Date: Sat, 20 Feb 2016 06:55:09 -0800
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On Fri, Feb 19, 2016 at 8:26 PM, Francesco Ruggeri <fruggeri@arista.com> wrote:
> Misconfigurations can result in local tunnel loops being created.
> __dev_queue_xmit catches packets caught in a loop and drops them,
> but the affected tunnels' needed_headroom can be corrupted in the
> process as it is recursively updated.

The problem with the patch is that it might force a pskb_expand_head
in the most common cases.
On the other hand if a loop is created then it may not be enough to
undo the configuration and the tunnel device itself should be
reinitialized.
Anybody have a better suggestion?

Thanks,
Francesco