Subject: Re: [PATCH net-next v2] Take care of xfrm policy when checking dst entries

From: Vlad Yasevich <[email-masked]>
Date: Mon, 10 Sep 2012 10:35:03 -0400

On 09/10/2012 09:22 AM, Nicolas Dichtel wrote:
> The goal of these patches is to fix the following problem: a session is
> established (TCP, SCTP) and after a new policy is inserted. The current
> code does not recalculate the route, thus the traffic is not encrypted.
>
> The patch propose to check flow_cache_genid value when checking a dst
> entry, which is incremented each time a policy is inserted or deleted.
>
> v2: use net->ipv4.rt_genid instead of flow_cache_genid (and thus save a test
>      in fast path). Also move it to net->rt_genid, to be able to use it for IPv6
>      too. Note that IPv6 will have one more test in fast path.
>
> Patches are tested with TCP and SCTP, IPv4 and IPv6.
>
> Comments are welcome.
>
> Regards,
> Nicolas
>

I am not sure this is right...  This has a side-effect that when an 
rt_cache_flush() is called, it invalidates IPv6 routes a well....

Its all fine and good do this when a new policy is added, but not when 
IPv4 routing table changes.

-vlad