ipv6: use ->ndo_tunnel_ctl in addrconf_set_dstaddr

Use the new ->ndo_tunnel_ctl instead of overriding the address limit
and using ->ndo_do_ioctl just to do a pointless user copy.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -2787,8 +2787,6 @@ static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
 		struct in6_ifreq *ireq)
 {
 	struct ip_tunnel_parm p = { };
-	mm_segment_t oldfs = get_fs();
-	struct ifreq ifr;
 	int err;
 
 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
@@ -2799,13 +2797,10 @@ static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
 	p.iph.ihl = 5;
 	p.iph.protocol = IPPROTO_IPV6;
 	p.iph.ttl = 64;
-	ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
 
-	if (!dev->netdev_ops->ndo_do_ioctl)
+	if (!dev->netdev_ops->ndo_tunnel_ctl)
 		return -EOPNOTSUPP;
-	set_fs(KERNEL_DS);
-	err = dev->netdev_ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
-	set_fs(oldfs);
+	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
 	if (err)
 		return err;