cfg80211: respect iface combinations when starting operation

devlist_mtx locking is changed to accomodate changes.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 4713cea9a2fa..a9260ac85cf1 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -805,8 +805,10 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
                 return -EBUSY;
 
         if (ntype != otype && netif_running(dev)) {
+                mutex_lock(&rdev->devlist_mtx);
                 err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
                                                     ntype);
+                mutex_unlock(&rdev->devlist_mtx);
                 if (err)
                         return err;
 
@@ -956,6 +958,7 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
         int i, j;
 
         ASSERT_RTNL();
+        lockdep_assert_held(&rdev->devlist_mtx);
 
         /* Always allow software iftypes */
         if (rdev->wiphy.software_iftypes & BIT(iftype))
@@ -979,7 +982,6 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
                 break;
         }
 
-        mutex_lock(&rdev->devlist_mtx);
         list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
                 if (wdev_iter == wdev)
                         continue;
@@ -999,10 +1001,8 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
                                 if (!used_channels[i] || used_channels[i] == ch)
                                         break;
 
-                        if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS) {
-                                mutex_unlock(&rdev->devlist_mtx);
+                        if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS)
                                 return -EBUSY;
-                        }
 
                         if (used_channels[i] == NULL) {
                                 used_channels[i] = ch;
@@ -1018,7 +1018,6 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
                 total++;
                 used_iftypes |= BIT(wdev_iter->iftype);
         }
-        mutex_unlock(&rdev->devlist_mtx);
 
         if (total == 1)
                 return 0;