ipvs: stop tot_stats estimator only under CONFIG_SYSCTL

[ Upstream commit 9802d21e ]

The tot_stats estimator is started only when CONFIG_SYSCTL
is defined. But it is stopped without checking CONFIG_SYSCTL.
Fix the crash by moving ip_vs_stop_estimator into
ip_vs_control_net_cleanup_sysctl.

The change is needed after commit 14e40546
("IPVS: Add __ip_vs_control_{init,cleanup}_sysctl()") from 2.6.39.

Cc: <stable@vger.kernel.org> # 3.15.x
Cc: <stable@vger.kernel.org> # 3.14.x
Cc: <stable@vger.kernel.org> # 3.12.x
Cc: <stable@vger.kernel.org> # 3.10.x
Cc: <stable@vger.kernel.org> # 3.2.x
Reported-by: Jet Chen <jet.chen@intel.com>
Tested-by: Jet Chen <jet.chen@intel.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Sgned-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

net/netfilter/ipvs/ip_vs_ctl.c

@@ -3765,6 +3765,7 @@ static void __net_exit ip_vs_control_net_cleanup_sysctl(struct net *net)
 	cancel_delayed_work_sync(&ipvs->defense_work);
 	cancel_work_sync(&ipvs->defense_work.work);
 	unregister_net_sysctl_table(ipvs->sysctl_hdr);
+	ip_vs_stop_estimator(net, &ipvs->tot_stats);
 }
 
 #else
@@ -3825,7 +3826,6 @@ void __net_exit ip_vs_control_net_cleanup(struct net *net)
 	 */
 	rcu_barrier();
 	ip_vs_trash_cleanup(net);
-	ip_vs_stop_estimator(net, &ipvs->tot_stats);
 	ip_vs_control_net_cleanup_sysctl(net);
 	remove_proc_entry("ip_vs_stats_percpu", net->proc_net);
 	remove_proc_entry("ip_vs_stats", net->proc_net);