Subject: Re: [net PATCH] ip_vti/ip6_vti: Clear skb->mark when resetting skb->dev in receive path

From: Steffen Klassert <[email-masked]>
Date: Mon, 18 May 2015 10:38:44 +0200

On Mon, May 18, 2015 at 04:31:21PM +0800, Herbert Xu wrote:
> On Mon, May 18, 2015 at 09:04:27AM +0200, Steffen Klassert wrote:
> >
> > The policy and state mark must match the tunnels i_key/o_key
> > on lookup. It is not required to set skb->mark, but we have
> > to make sure to use the tunnels gre keys as the mark when we
> > do a policy or state lookup.
> 
> So is it possible to restore the original mark after the lookups?

Yes, that's possible. We just did not restore it because it 
was cleared with skb_scrub_packet() right after the lookup.