From 176c39af29bc4edaf37f663553eeaacd47b5bc9c Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Tue, 3 Mar 2009 01:06:45 -0800 Subject: [PATCH] netns: fix addrconf_ifdown kernel panic When a network namespace is destroyed the network interfaces are all unregistered, making addrconf_ifdown called by the netdevice notifier. In the other hand, the addrconf exit method does a loop on the network devices and does addrconf_ifdown on each of them. But the ordering of the netns subsystem is not right because it uses the register_pernet_device instead of register_pernet_subsys. If we handle the loopback as any network device, we can safely use register_pernet_subsys. But if we use register_pernet_subsys, the addrconf exit method will do exactly what was already done with the unregistering of the network devices. So in definitive, this code is pointless. I removed the netns addrconf exit method and moved the code to the addrconf cleanup function. Signed-off-by: Daniel Lezcano Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 39 +++++++++------------------------------ 1 file changed, 9 insertions(+), 30 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 40fabdee42ae..1220e2c7831e 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -2611,9 +2611,6 @@ static int addrconf_ifdown(struct net_device *dev, int how) ASSERT_RTNL(); - if ((dev->flags & IFF_LOOPBACK) && how == 1) - how = 0; - rt6_ifdown(net, dev); neigh_ifdown(&nd_tbl, dev); @@ -4448,25 +4445,6 @@ int unregister_inet6addr_notifier(struct notifier_block *nb) EXPORT_SYMBOL(unregister_inet6addr_notifier); -static void addrconf_net_exit(struct net *net) -{ - struct net_device *dev; - - rtnl_lock(); - /* clean dev list */ - for_each_netdev(net, dev) { - if (__in6_dev_get(dev) == NULL) - continue; - addrconf_ifdown(dev, 1); - } - addrconf_ifdown(net->loopback_dev, 2); - rtnl_unlock(); -} - -static struct pernet_operations addrconf_net_ops = { - .exit = addrconf_net_exit, -}; - /* * Init / cleanup code */ @@ -4508,10 +4486,6 @@ int __init addrconf_init(void) if (err) goto errlo; - err = register_pernet_device(&addrconf_net_ops); - if (err) - return err; - register_netdevice_notifier(&ipv6_dev_notf); addrconf_verify(0); @@ -4541,15 +4515,22 @@ errlo: void addrconf_cleanup(void) { struct inet6_ifaddr *ifa; + struct net_device *dev; int i; unregister_netdevice_notifier(&ipv6_dev_notf); - unregister_pernet_device(&addrconf_net_ops); - unregister_pernet_subsys(&addrconf_ops); rtnl_lock(); + /* clean dev list */ + for_each_netdev(&init_net, dev) { + if (__in6_dev_get(dev) == NULL) + continue; + addrconf_ifdown(dev, 1); + } + addrconf_ifdown(init_net.loopback_dev, 2); + /* * Check hash table. */ @@ -4570,6 +4551,4 @@ void addrconf_cleanup(void) del_timer(&addr_chk_timer); rtnl_unlock(); - - unregister_pernet_subsys(&addrconf_net_ops); } -- 2.30.2