ipv6: data of fwmark_reflect sysctl needs to be updated on netns construction

Fixes: e110861f86094cd ("net: add a sysctl to reflect the fwmark on replies")
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
index 058f3ec..8183346 100644
--- a/net/ipv6/sysctl_net_ipv6.c
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -74,6 +74,7 @@
 	ipv6_table[0].data = &net->ipv6.sysctl.bindv6only;
 	ipv6_table[1].data = &net->ipv6.sysctl.anycast_src_echo_reply;
 	ipv6_table[2].data = &net->ipv6.sysctl.flowlabel_consistency;
+	ipv6_table[3].data = &net->ipv6.sysctl.fwmark_reflect;
 
 	ipv6_route_table = ipv6_route_sysctl_init(net);
 	if (!ipv6_route_table)