diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 29ba4ff..ec3e065 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -154,6 +154,11 @@ static void addrconf_type_change(struct net_device *dev,
 				 unsigned long event);
 static int addrconf_ifdown(struct net_device *dev, int how);
 
+static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
+						  int plen,
+						  const struct net_device *dev,
+						  u32 flags, u32 noflags);
+
 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
 static void addrconf_dad_timer(unsigned long data);
 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
@@ -250,12 +255,6 @@ static inline bool addrconf_qdisc_ok(const struct net_device *dev)
 	return !qdisc_tx_is_noop(dev);
 }
 
-/* Check if a route is valid prefix route */
-static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
-{
-	return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
-}
-
 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
 {
 	if (del_timer(&ifp->timer))
@@ -941,17 +940,15 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
 		struct in6_addr prefix;
 		struct rt6_info *rt;
-		struct net *net = dev_net(ifp->idev->dev);
-		struct flowi6 fl6 = {};
 
 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
-		fl6.flowi6_oif = ifp->idev->dev->ifindex;
-		fl6.daddr = prefix;
-		rt = (struct rt6_info *)ip6_route_lookup(net, &fl6,
-							 RT6_LOOKUP_F_IFACE);
 
-		if (rt != net->ipv6.ip6_null_entry &&
-		    addrconf_is_prefix_route(rt)) {
+		rt = addrconf_get_prefix_route(&prefix,
+					       ifp->prefix_len,
+					       ifp->idev->dev,
+					       0, RTF_GATEWAY | RTF_DEFAULT);
+
+		if (rt) {
 			if (onlink == 0) {
 				ip6_del_rt(rt);
 				rt = NULL;