1 files changed, 19 insertions, 6 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 363172527e43..0ea96c4d334d 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3271,14 +3271,24 @@ static void addrconf_gre_config(struct net_device *dev)
 static int fixup_permanent_addr(struct inet6_dev *idev,
 				struct inet6_ifaddr *ifp)
 {
-	if (!ifp->rt) {
-		struct rt6_info *rt;
+	/* rt6i_ref == 0 means the host route was removed from the
+	 * FIB, for example, if 'lo' device is taken down. In that
+	 * case regenerate the host route.
+	 */
+	if (!ifp->rt || !atomic_read(&ifp->rt->rt6i_ref)) {
+		struct rt6_info *rt, *prev;
 
 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
 		if (unlikely(IS_ERR(rt)))
 			return PTR_ERR(rt);
 
+		/* ifp->rt can be accessed outside of rtnl */
+		spin_lock(&ifp->lock);
+		prev = ifp->rt;
 		ifp->rt = rt;
+		spin_unlock(&ifp->lock);
+
+		ip6_rt_put(prev);
 	}
 
 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
@@ -3626,14 +3636,19 @@ restart:
 	INIT_LIST_HEAD(&del_list);
 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
 		struct rt6_info *rt = NULL;
+		bool keep;
 
 		addrconf_del_dad_work(ifa);
 
+		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
+			!addr_is_local(&ifa->addr);
+		if (!keep)
+			list_move(&ifa->if_list, &del_list);
+
 		write_unlock_bh(&idev->lock);
 		spin_lock_bh(&ifa->lock);
 
-		if (keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
-		    !addr_is_local(&ifa->addr)) {
+		if (keep) {
 			/* set state to skip the notifier below */
 			state = INET6_IFADDR_STATE_DEAD;
 			ifa->state = 0;
@@ -3645,8 +3660,6 @@ restart:
 		} else {
 			state = ifa->state;
 			ifa->state = INET6_IFADDR_STATE_DEAD;
-
-			list_move(&ifa->if_list, &del_list);
 		}
 
 		spin_unlock_bh(&ifa->lock);