From f2344a131bccdbfc5338e17fa71a807dee7944fa Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 18 May 2010 15:55:27 -0700 Subject: [PATCH] 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: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 2e42162c9042..7c769fa81d97 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -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; - } + if (ifp->flags & IFA_F_TENTATIVE && + ifp->state == INET6_IFADDR_STATE_DAD) + addrconf_dad_kick(ifp); spin_unlock(&ifp->lock); - addrconf_dad_kick(ifp); } read_unlock_bh(&idev->lock); } -- 2.30.2