mac80211: fix scan when operating on DFS channels in ETSI domains

[linux.git] / net / mac80211 / scan.c

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index adf94ba1ed77a5c44ae8479541d03c63466c62ab..4d31d9688dc230275c49b34c876b36ad2b635a1b 100644 (file)
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -520,10 +520,33 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local,
        return 0;
 }
 
+static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
+{
+       struct ieee80211_local *local = sdata->local;
+       struct ieee80211_sub_if_data *sdata_iter;
+
+       if (!ieee80211_is_radar_required(local))
+               return true;
+
+       if (!regulatory_pre_cac_allowed(local->hw.wiphy))
+               return false;
+
+       mutex_lock(&local->iflist_mtx);
+       list_for_each_entry(sdata_iter, &local->interfaces, list) {
+               if (sdata_iter->wdev.cac_started) {
+                       mutex_unlock(&local->iflist_mtx);
+                       return false;
+               }
+       }
+       mutex_unlock(&local->iflist_mtx);
+
+       return true;
+}
+
 static bool ieee80211_can_scan(struct ieee80211_local *local,
                               struct ieee80211_sub_if_data *sdata)
 {
-       if (ieee80211_is_radar_required(local))
+       if (!__ieee80211_can_leave_ch(sdata))
                return false;
 
        if (!list_empty(&local->roc_list))
@@ -630,7 +653,10 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 
        lockdep_assert_held(&local->mtx);
 
-       if (local->scan_req || ieee80211_is_radar_required(local))
+       if (local->scan_req)
+               return -EBUSY;
+
+       if (!__ieee80211_can_leave_ch(sdata))
                return -EBUSY;
 
        if (!ieee80211_can_scan(local, sdata)) {