3.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <eduma...@google.com>

[ Upstream commit 87757a917b0b3c0787e0563c679762152be81312 ]

unregister_netdevice_many() API is error prone and we had too
many bugs because of dangling LIST_HEAD on stacks.

See commit f87e6f47933e3e ("net: dont leave active on stack LIST_HEAD")

In fact, instead of making sure no caller leaves an active list_head,
just force a list_del() in the callee. No one seems to need to access
the list after unregister_netdevice_many()

Signed-off-by: Eric Dumazet <eduma...@google.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/net/macvlan.c |    1 -
 net/core/dev.c        |    5 ++++-
 net/core/rtnetlink.c  |    1 -
 net/mac80211/iface.c  |    1 -
 4 files changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -961,7 +961,6 @@ static int macvlan_device_event(struct n
                list_for_each_entry_safe(vlan, next, &port->vlans, list)
                        vlan->dev->rtnl_link_ops->dellink(vlan->dev, 
&list_kill);
                unregister_netdevice_many(&list_kill);
-               list_del(&list_kill);
                break;
        case NETDEV_PRE_TYPE_CHANGE:
                /* Forbid underlaying device to change its type. */
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5827,6 +5827,9 @@ EXPORT_SYMBOL(unregister_netdevice_queue
 /**
  *     unregister_netdevice_many - unregister many devices
  *     @head: list of devices
+ *
+ *  Note: As most callers use a stack allocated list_head,
+ *  we force a list_del() to make sure stack wont be corrupted later.
  */
 void unregister_netdevice_many(struct list_head *head)
 {
@@ -5836,6 +5839,7 @@ void unregister_netdevice_many(struct li
                rollback_registered_many(head);
                list_for_each_entry(dev, head, unreg_list)
                        net_set_todo(dev);
+               list_del(head);
        }
 }
 EXPORT_SYMBOL(unregister_netdevice_many);
@@ -6252,7 +6256,6 @@ static void __net_exit default_device_ex
                }
        }
        unregister_netdevice_many(&dev_kill_list);
-       list_del(&dev_kill_list);
        rtnl_unlock();
 }
 
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1601,7 +1601,6 @@ static int rtnl_dellink(struct sk_buff *
 
        ops->dellink(dev, &list_kill);
        unregister_netdevice_many(&list_kill);
-       list_del(&list_kill);
        return 0;
 }
 
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1746,7 +1746,6 @@ void ieee80211_remove_interfaces(struct
        }
        mutex_unlock(&local->iflist_mtx);
        unregister_netdevice_many(&unreg_list);
-       list_del(&unreg_list);
 
        list_for_each_entry_safe(sdata, tmp, &wdev_list, list) {
                list_del(&sdata->list);


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