cfg80211: process pending events when unregistering net device

libertas currently calls cfg80211_disconnected() when it is being
brought down. This causes an event to be allocated, but since the
wdev is already removed from the rdev by the time that the event
processing work executes, the event is never processed or freed.
http://article.gmane.org/gmane.linux.kernel.wireless.general/95666

Fix this leak, and other possible situations, by processing the event
queue when a device is being unregistered. Thanks to Johannes Berg for
the suggestion.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Cc: stable@vger.kernel.org
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 31b40cc4a9c3c59bac7986e3c5c8725153381179..dcd64d5b07aadfba26a799506452a9b04fe8e7d3 100644 (file)
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -952,6 +952,11 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
                 */
                synchronize_rcu();
                INIT_LIST_HEAD(&wdev->list);
+               /*
+                * Ensure that all events have been processed and
+                * freed.
+                */
+               cfg80211_process_wdev_events(wdev);
                break;
        case NETDEV_PRE_UP:
                if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 5206c6844fd735b5aac540a3afe7337ce79963d7..bc7430b54771af18e903ee1d263ede3b4eb1b78f 100644 (file)
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -426,6 +426,7 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
                          struct net_device *dev, enum nl80211_iftype ntype,
                          u32 *flags, struct vif_params *params);
 void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev);
+void cfg80211_process_wdev_events(struct wireless_dev *wdev);
 
 int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
                                 struct wireless_dev *wdev,

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 26f8cd30f712dc190d9e207e4dff989a75106c66..994e2f0cc7a8a12fc34cbe61fdee97afde3df10b 100644 (file)
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -735,7 +735,7 @@ void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
        wdev->connect_keys = NULL;
 }
 
-static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
+void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 {
        struct cfg80211_event *ev;
        unsigned long flags;