ipv6: Do not depend on rt->n in rt6_probe().

	 * Router Reachability Probe MUST be rate-limited

	 * to no more than one per minute.

	 */

	neigh = rt ? rt->n : NULL;

	if (!neigh)

		return;

	write_lock_bh(&neigh->lock);

	if (neigh->nud_state & NUD_VALID) {

		write_unlock_bh(&neigh->lock);

	if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))

		return;

	rcu_read_lock_bh();

	neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);

	if (neigh) {

		write_lock(&neigh->lock);

		if (neigh->nud_state & NUD_VALID)

			goto out;

	}

	if (!(neigh->nud_state & NUD_VALID) &&

	if (!neigh ||

	    time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {

		struct in6_addr mcaddr;

		struct in6_addr *target;

		neigh->updated = jiffies;

		write_unlock_bh(&neigh->lock);

		target = (struct in6_addr *)&neigh->primary_key;

		if (neigh)

			write_unlock(&neigh->lock);

		target = (struct in6_addr *)&rt->rt6i_gateway;

		addrconf_addr_solict_mult(target, &mcaddr);

		ndisc_send_ns(rt->dst.dev, NULL, target, &mcaddr, NULL);

	} else {

		write_unlock_bh(&neigh->lock);

out:

		write_unlock(&neigh->lock);

	}

	rcu_read_unlock_bh();

}

#else

static inline void rt6_probe(struct rt6_info *rt)