--- zzzz-none-000/linux-4.4.271/net/ipv6/addrconf.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/net/ipv6/addrconf.c	2023-04-19 10:22:30.000000000 +0000
@@ -1779,6 +1779,35 @@
 	return result;
 }
 
+/* ipv6_dev_find()
+ *	Find (and hold) net device that has the given address.
+ *	Or NULL on failure.
+ */
+struct net_device *ipv6_dev_find(struct net *net, struct in6_addr *addr,
+				 int strict)
+{
+	struct inet6_ifaddr *ifp;
+	struct net_device *dev;
+
+	ifp = ipv6_get_ifaddr(net, addr, NULL, strict);
+	if (!ifp)
+		return NULL;
+
+	if (!ifp->idev) {
+		in6_ifa_put(ifp);
+		return NULL;
+	}
+
+	dev = ifp->idev->dev;
+	if (dev)
+		dev_hold(dev);
+
+	in6_ifa_put(ifp);
+
+	return dev;
+}
+EXPORT_SYMBOL(ipv6_dev_find);
+
 /* Gets referenced address, destroys ifaddr */
 
 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
@@ -2064,6 +2093,7 @@
 	case ARPHRD_IEEE1394:
 		return addrconf_ifid_ieee1394(eui, dev);
 	case ARPHRD_TUNNEL6:
+	case ARPHRD_RAWIP:
 		return addrconf_ifid_ip6tnl(eui, dev);
 	}
 	return -1;
@@ -3088,7 +3118,8 @@
 	    (dev->type != ARPHRD_IEEE802154) &&
 	    (dev->type != ARPHRD_IEEE1394) &&
 	    (dev->type != ARPHRD_TUNNEL6) &&
-	    (dev->type != ARPHRD_6LOWPAN)) {
+	    (dev->type != ARPHRD_6LOWPAN) &&
+            (dev->type != ARPHRD_RAWIP)) {
 		/* Alas, we support only Ethernet autoconfiguration. */
 		return;
 	}
@@ -3356,6 +3387,7 @@
 	struct net *net = dev_net(dev);
 	struct inet6_dev *idev;
 	struct inet6_ifaddr *ifa;
+	bool was_ready;
 	int state, i;
 
 	ASSERT_RTNL();
@@ -3402,7 +3434,10 @@
 
 	addrconf_del_rs_timer(idev);
 
-	/* Step 2: clear flags for stateless addrconf */
+	/* Step 2: clear flags for stateless addrconf, repeated down
+	 *         detection
+	 */
+	was_ready = idev->if_flags & IF_READY;
 	if (!how)
 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
 
@@ -3455,7 +3490,7 @@
 	if (how) {
 		ipv6_ac_destroy_dev(idev);
 		ipv6_mc_destroy_dev(idev);
-	} else {
+	} else if (was_ready) {
 		ipv6_mc_down(idev);
 	}