From 2de795707294972f6c34bae9de713e502c431296 Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Wed, 27 Oct 2010 18:16:49 +0000 Subject: [PATCH] ipv6: addrconf: don't remove address state on ifdown if the address is being kept Currently, addrconf_ifdown does not delete statically configured IPv6 addresses when the interface is brought down. The intent is that when the interface comes back up the address will be usable again. However, this doesn't actually work, because the system stops listening on the corresponding solicited-node multicast address, so the address cannot respond to neighbor solicitations and thus receive traffic. Also, the code notifies the rest of the system that the address is being deleted (e.g, RTM_DELADDR), even though it is not. Fix it so that none of this state is updated if the address is being kept on the interface. Tested: Added a statically configured IPv6 address to an interface, started ping, brought link down, brought link up again. When link came up ping kept on going and "ip -6 maddr" showed that the host was still subscribed to there Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index e048ec62d109..b41ce0f0d514 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -2740,10 +2740,6 @@ 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); - - in6_ifa_hold(ifa); } else { list_del(&ifa->if_list); @@ -2758,19 +2754,15 @@ static int addrconf_ifdown(struct net_device *dev, int how) ifa->state = INET6_IFADDR_STATE_DEAD; spin_unlock_bh(&ifa->state_lock); - if (state == INET6_IFADDR_STATE_DEAD) - goto put_ifa; + if (state == INET6_IFADDR_STATE_DEAD) { + in6_ifa_put(ifa); + } else { + __ipv6_ifa_notify(RTM_DELADDR, ifa); + atomic_notifier_call_chain(&inet6addr_chain, + NETDEV_DOWN, ifa); + } + write_lock_bh(&idev->lock); } - - __ipv6_ifa_notify(RTM_DELADDR, ifa); - if (ifa->state == INET6_IFADDR_STATE_DEAD) - atomic_notifier_call_chain(&inet6addr_chain, - NETDEV_DOWN, ifa); - -put_ifa: - in6_ifa_put(ifa); - - write_lock_bh(&idev->lock); } list_splice(&keep_list, &idev->addr_list); -- 2.39.5