cfg80211: fix NETDEV_UNREGISTER notifier
It's possible to get the NETDEV_UNREGISTER callback multiple
times (see net/core/dev.c:netdev_wait_allrefs) and this will
completely mess up our cleanup code. To avoid that, clean up
only when the interface is still on the wiphy interface list
from which it's removed on the first NETDEV_UNREGISTER call.
Signed-off-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 755cdf1..1493285 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -725,15 +725,22 @@
break;
case NETDEV_UNREGISTER:
mutex_lock(&rdev->devlist_mtx);
+ /*
+ * It is possible to get NETDEV_UNREGISTER
+ * multiple times. To detect that, check
+ * that the interface is still on the list
+ * of registered interfaces, and only then
+ * remove and clean it up.
+ */
if (!list_empty(&wdev->list)) {
sysfs_remove_link(&dev->dev.kobj, "phy80211");
list_del_init(&wdev->list);
+ mutex_destroy(&wdev->mtx);
+#ifdef CONFIG_WIRELESS_EXT
+ kfree(wdev->wext.keys);
+#endif
}
mutex_unlock(&rdev->devlist_mtx);
- mutex_destroy(&wdev->mtx);
-#ifdef CONFIG_WIRELESS_EXT
- kfree(wdev->wext.keys);
-#endif
break;
case NETDEV_PRE_UP:
if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))