[IPV6] MCAST: Fix joining all-node multicast group on device initialization.

Join all-node multicast group after assignment of dev->ip6_ptr
because it must be assigned when ipv6_dev_mc_inc() is called.
This fixes Bug#7817, reported by <gernoth@informatik.uni-erlangen.de>.

Closes: 7817
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -341,6 +341,7 @@ void in6_dev_finish_destroy(struct inet6_dev *idev)
 static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
 {
 	struct inet6_dev *ndev;
+	struct in6_addr maddr;
 
 	ASSERT_RTNL();
 
@@ -425,6 +426,11 @@ static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
 #endif
 	/* protected by rtnl_lock */
 	rcu_assign_pointer(dev->ip6_ptr, ndev);
+
+	/* Join all-node multicast group */
+	ipv6_addr_all_nodes(&maddr);
+	ipv6_dev_mc_inc(dev, &maddr);
+
 	return ndev;
 }
 

net/ipv6/mcast.c

@@ -2258,8 +2258,6 @@ void ipv6_mc_up(struct inet6_dev *idev)
 
 void ipv6_mc_init_dev(struct inet6_dev *idev)
 {
-	struct in6_addr maddr;
-
 	write_lock_bh(&idev->lock);
 	rwlock_init(&idev->mc_lock);
 	idev->mc_gq_running = 0;
@@ -2275,10 +2273,6 @@ void ipv6_mc_init_dev(struct inet6_dev *idev)
 	idev->mc_maxdelay = IGMP6_UNSOLICITED_IVAL;
 	idev->mc_v1_seen = 0;
 	write_unlock_bh(&idev->lock);
-
-	/* Add all-nodes address. */
-	ipv6_addr_all_nodes(&maddr);
-	ipv6_dev_mc_inc(idev->dev, &maddr);
 }
 
 /*