[NETFILTER]: nf_nat: properly use RCU for ip_nat_decode_session

We need to use rcu_assign_pointer/rcu_dereference to avoid races.
Also remove an obsolete CONFIG_IP_NAT_NEEDED ifdef.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2 files changed