cfg80211: add missing device list locking

When calling into the wext code from the NETDEV_UP
notifier, we need to hold the devlist_mtx mutex as
the wext code ends up calling into channel checks.

Reported-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 62e1ac00879b..e630648fef79 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -710,6 +710,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
         case NETDEV_UP:
 #ifdef CONFIG_WIRELESS_EXT
                 cfg80211_lock_rdev(rdev);
+                mutex_lock(&rdev->devlist_mtx);
                 wdev_lock(wdev);
                 switch (wdev->iftype) {
                 case NL80211_IFTYPE_ADHOC:
@@ -722,6 +723,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
                         break;
                 }
                 wdev_unlock(wdev);
+                mutex_unlock(&rdev->devlist_mtx);
                 cfg80211_unlock_rdev(rdev);
 #endif
                 break;