ipv6: Be smarter with null_entry handling in ip6_pol_route_lookup (af52a52c) · Commits · 戴 / test

net/ipv6/route.c

+13 −12

Original line number	Diff line number	Diff line
		@@ -1062,36 +1062,37 @@ static struct rt6_info ip6_pol_route_lookup(struct net net,
		fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
		restart:
		f6i = rcu_dereference(fn->leaf);
		if (!f6i) {
		if (!f6i)
		f6i = net->ipv6.fib6_null_entry;
		} else {
		else
		f6i = rt6_device_match(net, f6i, &fl6->saddr,
		fl6->flowi6_oif, flags);
		if (f6i->fib6_nsiblings && fl6->flowi6_oif == 0)
		f6i = fib6_multipath_select(net, f6i, fl6,
		fl6->flowi6_oif, skb,
		flags);
		}

		if (f6i == net->ipv6.fib6_null_entry) {
		fn = fib6_backtrack(fn, &fl6->saddr);
		if (fn)
		goto restart;
		}

		trace_fib6_table_lookup(net, f6i, table, fl6);
		rt = net->ipv6.ip6_null_entry;
		dst_hold(&rt->dst);
		goto out;
		}

		if (f6i->fib6_nsiblings && fl6->flowi6_oif == 0)
		f6i = fib6_multipath_select(net, f6i, fl6, fl6->flowi6_oif, skb,
		flags);
		/* Search through exception table */
		rt = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
		if (rt) {
		if (ip6_hold_safe(net, &rt))
		dst_use_noref(&rt->dst, jiffies);
		} else if (f6i == net->ipv6.fib6_null_entry) {
		rt = net->ipv6.ip6_null_entry;
		dst_hold(&rt->dst);
		} else {
		rt = ip6_create_rt_rcu(f6i);
		}

		out:
		trace_fib6_table_lookup(net, f6i, table, fl6);

		rcu_read_unlock();

		return rt;