Commit f2344a13 authored by Herbert Xu's avatar Herbert Xu Committed by David S. Miller
Browse files

ipv6: Use POSTDAD state 



This patch makes use of the new POSTDAD state.  This prevents
a race between DAD completion and failure.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4c5ff6a6

net/ipv6/addrconf.c

+24 −5
Original line number Diff line number Diff line
@@ -1406,10 +1406,27 @@ static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed) 
		ipv6_del_addr(ifp);

}



static int addrconf_dad_end(struct inet6_ifaddr *ifp)

{

	int err = -ENOENT;



	spin_lock(&ifp->state_lock);

	if (ifp->state == INET6_IFADDR_STATE_DAD) {

		ifp->state = INET6_IFADDR_STATE_POSTDAD;

		err = 0;

	}

	spin_unlock(&ifp->state_lock);



	return err;

}



void addrconf_dad_failure(struct inet6_ifaddr *ifp)

{

	struct inet6_dev *idev = ifp->idev;



	if (addrconf_dad_end(ifp))

		return;



	if (net_ratelimit())

		printk(KERN_INFO "%s: IPv6 duplicate address %pI6c detected!\n",

			ifp->idev->dev->name, &ifp->addr);
@@ -2712,6 +2729,7 @@ static int addrconf_ifdown(struct net_device *dev, int how) 


			/* Flag it for later restoration when link comes up */

			ifa->flags |= IFA_F_TENTATIVE;

			ifa->state = INET6_IFADDR_STATE_DAD;



			write_unlock_bh(&idev->lock);
@@ -2883,6 +2901,9 @@ static void addrconf_dad_timer(unsigned long data) 
	struct inet6_dev *idev = ifp->idev;

	struct in6_addr mcaddr;



	if (!ifp->probes && addrconf_dad_end(ifp))

		goto out;



	read_lock(&idev->lock);

	if (idev->dead || !(idev->if_flags & IF_READY)) {

		read_unlock(&idev->lock);
@@ -2956,12 +2977,10 @@ static void addrconf_dad_run(struct inet6_dev *idev) 
	read_lock_bh(&idev->lock);

	list_for_each_entry(ifp, &idev->addr_list, if_list) {

		spin_lock(&ifp->lock);

		if (!(ifp->flags & IFA_F_TENTATIVE)) {

			spin_unlock(&ifp->lock);

			continue;

		}

		spin_unlock(&ifp->lock);

		if (ifp->flags & IFA_F_TENTATIVE &&

		    ifp->state == INET6_IFADDR_STATE_DAD)

			addrconf_dad_kick(ifp);

		spin_unlock(&ifp->lock);

	}

	read_unlock_bh(&idev->lock);

}