xfrm interface: ifname may be wrong in logs

The ifname is copied when the interface is created, but is never updated
later. In fact, this property is used only in one error message, where the
netdevice pointer is available, thus let's use it.

Fixes: f203b76d ("xfrm: Add virtual xfrm interfaces")
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -983,7 +983,6 @@ static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 
 struct xfrm_if_parms {
-	char name[IFNAMSIZ];	/* name of XFRM device */
 	int link;		/* ifindex of underlying L2 interface */
 	u32 if_id;		/* interface identifyer */
 };

net/xfrm/xfrm_interface.c

@@ -145,8 +145,6 @@ static int xfrmi_create(struct net_device *dev)
 	if (err < 0)
 		goto out;
 
-	strcpy(xi->p.name, dev->name);
-
 	dev_hold(dev);
 	xfrmi_link(xfrmn, xi);
 
@@ -294,7 +292,7 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	if (tdev == dev) {
 		stats->collisions++;
 		net_warn_ratelimited("%s: Local routing loop detected!\n",
-				     xi->p.name);
+				     dev->name);
 		goto tx_err_dst_release;
 	}
 
@@ -638,12 +636,6 @@ static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
 	int err;
 
 	xfrmi_netlink_parms(data, &p);
-
-	if (!tb[IFLA_IFNAME])
-		return -EINVAL;
-
-	nla_strlcpy(p.name, tb[IFLA_IFNAME], IFNAMSIZ);
-
 	xi = xfrmi_locate(net, &p);
 	if (xi)
 		return -EEXIST;