Subject: Re: switching network namespace midway

From: Stephen Hemminger <[email-masked]>
Date: Thu, 25 Oct 2012 09:21:05 -0700

I noticed that the L2TP sockets are not being moved to the correct name
space.

Something like this is probably needed.

--- a/net/l2tp/l2tp_core.c	2012-10-25 09:11:15.691271882 -0700
+++ b/net/l2tp/l2tp_core.c	2012-10-25 09:18:58.746621418 -0700
@@ -1357,7 +1357,10 @@ static void l2tp_tunnel_free(struct l2tp
  * userspace. This is used for static tunnels where there is no
  * managing L2TP daemon.
  */
-static int l2tp_tunnel_sock_create(u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, struct socket **sockp)
+static int l2tp_tunnel_sock_create(struct net *net,
+				   u32 tunnel_id, u32 peer_tunnel_id,
+				   struct l2tp_tunnel_cfg *cfg,
+				   struct socket **sockp)
 {
 	int err = -EINVAL;
 	struct sockaddr_in udp_addr;
@@ -1372,11 +1375,12 @@ static int l2tp_tunnel_sock_create(u32 t
 	case L2TP_ENCAPTYPE_UDP:
 #if IS_ENABLED(CONFIG_IPV6)
 		if (cfg->local_ip6 && cfg->peer_ip6) {
-			err = sock_create(AF_INET6, SOCK_DGRAM, 0, sockp);
+			err = sock_create_kern(AF_INET6, SOCK_DGRAM, 0, sockp);
 			if (err < 0)
 				goto out;
 
 			sock = *sockp;
+			sk_change(sock->sk, net);
 
 			memset(&udp6_addr, 0, sizeof(udp6_addr));
 			udp6_addr.sin6_family = AF_INET6;
@@ -1400,11 +1404,12 @@ static int l2tp_tunnel_sock_create(u32 t
 		} else
 #endif
 		{
-			err = sock_create(AF_INET, SOCK_DGRAM, 0, sockp);
+			err = sock_create_kern(AF_INET, SOCK_DGRAM, 0, sockp);
 			if (err < 0)
 				goto out;
 
 			sock = *sockp;
+			sk_change(sock->sk, net);
 
 			memset(&udp_addr, 0, sizeof(udp_addr));
 			udp_addr.sin_family = AF_INET;
@@ -1433,7 +1438,7 @@ static int l2tp_tunnel_sock_create(u32 t
 	case L2TP_ENCAPTYPE_IP:
 #if IS_ENABLED(CONFIG_IPV6)
 		if (cfg->local_ip6 && cfg->peer_ip6) {
-			err = sock_create(AF_INET6, SOCK_DGRAM, IPPROTO_L2TP,
+			err = sock_create_kern(AF_INET6, SOCK_DGRAM, IPPROTO_L2TP,
 					  sockp);
 			if (err < 0)
 				goto out;
@@ -1462,12 +1467,13 @@ static int l2tp_tunnel_sock_create(u32 t
 		} else
 #endif
 		{
-			err = sock_create(AF_INET, SOCK_DGRAM, IPPROTO_L2TP,
+			err = sock_create_kern(AF_INET, SOCK_DGRAM, IPPROTO_L2TP,
 					  sockp);
 			if (err < 0)
 				goto out;
 
 			sock = *sockp;
+			sk_change(sock->sk, net);
 
 			memset(&ip_addr, 0, sizeof(ip_addr));
 			ip_addr.l2tp_family = AF_INET;
@@ -1517,7 +1523,8 @@ int l2tp_tunnel_create(struct net *net,
 	 * kernel socket.
 	 */
 	if (fd < 0) {
-		err = l2tp_tunnel_sock_create(tunnel_id, peer_tunnel_id, cfg, &sock);
+		err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id,
+					      cfg, &sock);
 		if (err < 0)
 			goto err;
 	} else {