l2tp: Fix inet_opt conversion.
We don't actually hold the socket lock at this point, so the rcu_dereference_protected() isn't' correct. Thanks to Eric Dumazet for pointing this out. Thankfully, we're only interested in fetching the faddr value if srr is enabled, so we can simply make this an RCU sequence and use plain rcu_dereference(). Reported-by: Eric Dumazet <firstname.lastname@example.org> Signed-off-by: David S. Miller <email@example.com>