@@ -1623,6 +1623,15 @@ static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
return ip6_tnl_update(t, &p);
}
+static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct net *net = dev_net(dev);
+ struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
+
+ if (dev != ip6n->fb_tnl_dev)
+ unregister_netdevice_queue(dev, head);
+}
+
static size_t ip6_tnl_get_size(const struct net_device *dev)
{
return
@@ -1687,6 +1696,7 @@ static struct rtnl_link_ops ip6_link_ops __read_mostly = {
.validate = ip6_tnl_validate,
.newlink = ip6_tnl_newlink,
.changelink = ip6_tnl_changelink,
+ .dellink = ip6_tnl_dellink,
.get_size = ip6_tnl_get_size,
.fill_info = ip6_tnl_fill_info,
};
This is a note to let you know that I have just added a patch titled ip6tnl: fix double free of fb_tnl_dev on exit to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From bad1e33c6a96392413b07e7269d6c781b1dba8c4 Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel <nicolas.dichtel@6wind.com> Date: Fri, 31 Jan 2014 09:24:06 +0100 Subject: ip6tnl: fix double free of fb_tnl_dev on exit [ No relevant upstream commit. ] This problem was fixed upstream by commit 1e9f3d6f1c40 ("ip6tnl: fix use after free of fb_tnl_dev"). The upstream patch depends on upstream commit 0bd8762824e7 ("ip6tnl: add x-netns support"), which was not backported into 3.10 branch. First, explain the problem: when the ip6_tunnel module is unloaded, ip6_tunnel_cleanup() is called. rmmod ip6_tunnel => ip6_tunnel_cleanup() => rtnl_link_unregister() => __rtnl_kill_links() => for_each_netdev(net, dev) { if (dev->rtnl_link_ops == ops) ops->dellink(dev, &list_kill); } At this point, the FB device is deleted (and all ip6tnl tunnels). => unregister_pernet_device() => unregister_pernet_operations() => ops_exit_list() => ip6_tnl_exit_net() => ip6_tnl_destroy_tunnels() => t = rtnl_dereference(ip6n->tnls_wc[0]); unregister_netdevice_queue(t->dev, &list); We delete the FB device a second time here! The previous fix removes these lines, which fix this double free. But the patch introduces a memory leak when a netns is destroyed, because the FB device is never deleted. By adding an rtnl ops which delete all ip6tnl device excepting the FB device, we can keep this exlicit removal in ip6_tnl_destroy_tunnels(). CC: Steven Rostedt <rostedt@goodmis.org> CC: Willem de Bruijn <willemb@google.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: Steven Rostedt <srostedt@redhat.com> Tested-by: Steven Rostedt <srostedt@redhat.com> (and our entire MRG team) Tested-by: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com> Tested-by: John Kacur <jkacur@redhat.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- net/ipv6/ip6_tunnel.c | 10 ++++++++++ 1 file changed, 10 insertions(+) -- 1.8.3.2