ovpn: track UDP socket route key for peer dst cache

ovpn stores the route used to transmit UDP packets in a per-peer dst
cache. A cached dst is only valid for the route lookup inputs used when
it was resolved.

Some of those inputs are mutable while userspace still owns the UDP
socket. In particular, changes to the socket mark or UDP source port do
not invalidate ovpn's peer dst cache, so ovpn can keep using a route
selected with an old socket route key.

Replace the cached mark with a route key containing the socket-owned
lookup inputs currently used by ovpn, and reset the peer dst cache when
the key changes. Before storing a newly looked-up dst, recheck the route
key under the peer lock so a dst resolved for stale socket state is not
published.

Fixes: 08857b5ec5d9 ("ovpn: implement basic TX path (UDP)")
Signed-off-by: Ralf Lici <ralf@mandelbit.com>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>

0 files changed, 0 insertions, 0 deletions