[NETNS][IPV6] route6 - pass always a valid socket to ip6_dst_lookup

The ip6_dst_lookup receive a socket as parameter. In some part of the code
it is called with a NULL socket parameter. We want to rely on the socket
to retrieve the network namespace, so we always pass a valid socket in all
cases.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 161afd1..9370185 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -913,7 +913,7 @@
 	int err;
 
 	if (*dst == NULL)
-		*dst = ip6_route_output(&init_net, sk, fl);
+		*dst = ip6_route_output(sk->sk_net, sk, fl);
 
 	if ((err = (*dst)->error))
 		goto out_err_release;
@@ -954,7 +954,7 @@
 				dst_release(*dst);
 				memcpy(&fl_gw, fl, sizeof(struct flowi));
 				memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr));
-				*dst = ip6_route_output(&init_net, sk, &fl_gw);
+				*dst = ip6_route_output(sk->sk_net, sk, &fl_gw);
 				if ((err = (*dst)->error))
 					goto out_err_release;
 			}