netns: register net.ipv4.route.flush in each namespace

Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/netns/ipv4.h

@@ -18,6 +18,7 @@ struct netns_ipv4 {
 	struct ctl_table_header	*forw_hdr;
 	struct ctl_table_header	*frags_hdr;
 	struct ctl_table_header	*ipv4_hdr;
+	struct ctl_table_header *route_hdr;
 #endif
 	struct ipv4_devconf	*devconf_all;
 	struct ipv4_devconf	*devconf_dflt;

net/ipv4/route.c

@@ -2835,6 +2835,7 @@ static int ipv4_sysctl_rtcache_flush(ctl_table *ctl, int write,
 {
 	if (write) {
 		int flush_delay;
+		struct net *net;
 		static DEFINE_MUTEX(flush_mutex);
 
 		mutex_lock(&flush_mutex);
@@ -2843,7 +2844,8 @@ static int ipv4_sysctl_rtcache_flush(ctl_table *ctl, int write,
 		ctl->data = NULL;
 		mutex_unlock(&flush_mutex);
 
-		rt_cache_flush(&init_net, flush_delay);
+		net = (struct net *)ctl->extra1;
+		rt_cache_flush(net, flush_delay);
 		return 0;
 	}
 
@@ -2859,23 +2861,17 @@ static int ipv4_sysctl_rtcache_flush_strategy(ctl_table *table,
 						size_t newlen)
 {
 	int delay;
+	struct net *net;
 	if (newlen != sizeof(int))
 		return -EINVAL;
 	if (get_user(delay, (int __user *)newval))
 		return -EFAULT;
-	rt_cache_flush(&init_net, delay);
+	net = (struct net *)table->extra1;
+	rt_cache_flush(net, delay);
 	return 0;
 }
 
 ctl_table ipv4_route_table[] = {
-	{
-		.ctl_name 	= NET_IPV4_ROUTE_FLUSH,
-		.procname	= "flush",
-		.maxlen		= sizeof(int),
-		.mode		= 0200,
-		.proc_handler	= &ipv4_sysctl_rtcache_flush,
-		.strategy	= &ipv4_sysctl_rtcache_flush_strategy,
-	},
 	{
 		.ctl_name	= NET_IPV4_ROUTE_GC_THRESH,
 		.procname	= "gc_thresh",
@@ -3014,6 +3010,66 @@ ctl_table ipv4_route_table[] = {
 	},
 	{ .ctl_name = 0 }
 };
+
+static __net_initdata struct ctl_path ipv4_route_path[] = {
+	{ .procname = "net", .ctl_name = CTL_NET, },
+	{ .procname = "ipv4", .ctl_name = NET_IPV4, },
+	{ .procname = "route", .ctl_name = NET_IPV4_ROUTE, },
+	{ },
+};
+
+
+static struct ctl_table ipv4_route_flush_table[] = {
+	{
+		.ctl_name 	= NET_IPV4_ROUTE_FLUSH,
+		.procname	= "flush",
+		.maxlen		= sizeof(int),
+		.mode		= 0200,
+		.proc_handler	= &ipv4_sysctl_rtcache_flush,
+		.strategy	= &ipv4_sysctl_rtcache_flush_strategy,
+	},
+	{ .ctl_name = 0 },
+};
+
+static __net_init int sysctl_route_net_init(struct net *net)
+{
+	struct ctl_table *tbl;
+
+	tbl = ipv4_route_flush_table;
+	if (net != &init_net) {
+		tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
+		if (tbl == NULL)
+			goto err_dup;
+	}
+	tbl[0].extra1 = net;
+
+	net->ipv4.route_hdr =
+		register_net_sysctl_table(net, ipv4_route_path, tbl);
+	if (net->ipv4.route_hdr == NULL)
+		goto err_reg;
+	return 0;
+
+err_reg:
+	if (tbl != ipv4_route_flush_table)
+		kfree(tbl);
+err_dup:
+	return -ENOMEM;
+}
+
+static __net_exit void sysctl_route_net_exit(struct net *net)
+{
+	struct ctl_table *tbl;
+
+	tbl = net->ipv4.route_hdr->ctl_table_arg;
+	unregister_net_sysctl_table(net->ipv4.route_hdr);
+	BUG_ON(tbl == ipv4_route_flush_table);
+	kfree(tbl);
+}
+
+static __net_initdata struct pernet_operations sysctl_route_ops = {
+	.init = sysctl_route_net_init,
+	.exit = sysctl_route_net_exit,
+};
 #endif
 
 #ifdef CONFIG_NET_CLS_ROUTE
@@ -3090,6 +3146,9 @@ int __init ip_rt_init(void)
 #endif
 	rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL);
 
+#ifdef CONFIG_SYSCTL
+	register_pernet_subsys(&sysctl_route_ops);
+#endif
 	return rc;
 }