[PATCH 4/12] L2 network namespace: devinet sysctl's checks

[Dmitry Mishin]

This patch prohibits sysctl's registrations for devices, initialized in non-init
network namespace. This is required due to absense of the sysctl virtualization.

Signed-off-by: Dmitry Mishin <dim at openvz.org>

---
 net/ipv4/devinet.c |   26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

--- linux-2.6.19-rc6-mm2.orig/net/ipv4/devinet.c
+++ linux-2.6.19-rc6-mm2/net/ipv4/devinet.c
@@ -161,8 +161,9 @@ struct in_device *inetdev_init(struct ne
 	/* Reference in_dev->dev */
 	dev_hold(dev);
 #ifdef CONFIG_SYSCTL
-	neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
-			      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
+	if (current_net_ns == &init_net_ns)
+		neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
+				NET_IPV4_NEIGH, "ipv4", NULL, NULL);
 #endif
 
 	/* Account for reference dev->ip_ptr */
@@ -170,7 +171,8 @@ struct in_device *inetdev_init(struct ne
 	rcu_assign_pointer(dev->ip_ptr, in_dev);
 
 #ifdef CONFIG_SYSCTL
-	devinet_sysctl_register(in_dev, &in_dev->cnf);
+	if (current_net_ns == &init_net_ns)
+		devinet_sysctl_register(in_dev, &in_dev->cnf);
 #endif
 	ip_mc_init_dev(in_dev);
 	if (dev->flags & IFF_UP)
@@ -210,13 +212,15 @@ static void inetdev_destroy(struct in_de
 	}
 
 #ifdef CONFIG_SYSCTL
-	devinet_sysctl_unregister(&in_dev->cnf);
+	if (current_net_ns == &init_net_ns)
+		devinet_sysctl_unregister(&in_dev->cnf);
 #endif
 
 	dev->ip_ptr = NULL;
 
 #ifdef CONFIG_SYSCTL
-	neigh_sysctl_unregister(in_dev->arp_parms);
+	if (current_net_ns == &init_net_ns)
+		neigh_sysctl_unregister(in_dev->arp_parms);
 #endif
 	neigh_parms_release(&arp_tbl, in_dev->arp_parms);
 	arp_ifdown(dev);
@@ -1104,11 +1108,13 @@ static int inetdev_event(struct notifier
 		inetdev_changename(dev, in_dev);
 
 #ifdef CONFIG_SYSCTL
-		devinet_sysctl_unregister(&in_dev->cnf);
-		neigh_sysctl_unregister(in_dev->arp_parms);
-		neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
-				      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
-		devinet_sysctl_register(in_dev, &in_dev->cnf);
+		if (current_net_ns == &init_net_ns) {
+			devinet_sysctl_unregister(&in_dev->cnf);
+			neigh_sysctl_unregister(in_dev->arp_parms);
+			neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
+					      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
+			devinet_sysctl_register(in_dev, &in_dev->cnf);
+		}
 #endif
 		break;
 	}