[NETFILTER]: ctnetlink: make sure event order is correct

The following sequence is displayed during events dumping of an ICMP
connection: [NEW] [DESTROY] [UPDATE]

This happens because the event IPCT_DESTROY is delivered in
death_by_timeout(), that is called from the icmp protocol helper
(ct->timeout.function) once we see the reply.

To fix this, we move this event to destroy_conntrack().
Signed-off-by: NPablo Neira Ayuso <pablo@eurodev.net>
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ip_conntrack_core.c

@@ -316,6 +316,7 @@ destroy_conntrack(struct nf_conntrack *nfct)
 	IP_NF_ASSERT(atomic_read(&nfct->use) == 0);
 	IP_NF_ASSERT(!timer_pending(&ct->timeout));
 
+	ip_conntrack_event(IPCT_DESTROY, ct);
 	set_bit(IPS_DYING_BIT, &ct->status);
 
 	/* To make sure we don't get any weird locking issues here:
@@ -355,7 +356,6 @@ static void death_by_timeout(unsigned long ul_conntrack)
 {
 	struct ip_conntrack *ct = (void *)ul_conntrack;
 
-	ip_conntrack_event(IPCT_DESTROY, ct);
 	write_lock_bh(&ip_conntrack_lock);
 	/* Inside lock so preempt is disabled on module removal path.
 	 * Otherwise we can get spurious warnings. */