geneve: move debug check after netdev unregister

[ Upstream commit 208109412c87bb96ae6c4b5194a799c67f166580 ]

The debug check must be done after unregister_netdevice_many() call --
the list_del() for this is done inside .ndo_stop.

Fixes: 720e7914badf ("geneve: speedup geneve tunnels dismantle")
Reported-and-tested-by: <syzbot+68a8ed58e3d17c700de5@syzkaller.appspotmail.com>
Cc: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 5c6b7fc04ea6294b6592b23b278d3b70600ea05a..730ab57201bdb222a668304f1afd6d28a7e0c2b0 100644 (file)
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1845,8 +1845,6 @@ static void geneve_destroy_tunnels(struct net *net, struct list_head *head)
                if (!net_eq(dev_net(geneve->dev), net))
                        unregister_netdevice_queue(geneve->dev, head);
        }
-
-       WARN_ON_ONCE(!list_empty(&gn->sock_list));
 }
 
 static void __net_exit geneve_exit_batch_net(struct list_head *net_list)
@@ -1861,6 +1859,12 @@ static void __net_exit geneve_exit_batch_net(struct list_head *net_list)
        /* unregister the devices gathered above */
        unregister_netdevice_many(&list);
        rtnl_unlock();
+
+       list_for_each_entry(net, net_list, exit_list) {
+               const struct geneve_net *gn = net_generic(net, geneve_net_id);
+
+               WARN_ON_ONCE(!list_empty(&gn->sock_list));
+       }
 }
 
 static struct pernet_operations geneve_net_ops = {