mac80211: count interfaces correctly for combination checks

[ Upstream commit 0f611d28fc2e13cfec64e1c544c16a086886805a ]

Since moving the interface combination checks to mac80211, it's
broken because it now only considers interfaces with an assigned
channel context, so for example any interface that isn't active
can still be up, which is clearly an issue; also, in particular
P2P-Device wdevs are an issue since they never have a chanctx.

Fix this by counting running interfaces instead the ones with a
channel context assigned.

Cc: stable@vger.kernel.org [3.16+]
Fixes: 73de86a38962b ("cfg80211/mac80211: move interface counting for combination check to mac80211")
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
[rewrite commit message, dig out the commit it fixes]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 3c61060a4d2b75bd89d4a792dde8b4721eb435dc..0043256df4862cea0f518f2f90e5047bae63ef01 100644 (file)
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -3050,7 +3050,7 @@ int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
                wdev_iter = &sdata_iter->wdev;
 
                if (sdata_iter == sdata ||
-                   rcu_access_pointer(sdata_iter->vif.chanctx_conf) == NULL ||
+                   !ieee80211_sdata_running(sdata_iter) ||
                    local->hw.wiphy->software_iftypes & BIT(wdev_iter->iftype))
                        continue;