mac80211: fix monitor mode channel reporting

When not using channel contexts with only monitor mode interfaces being
active, report local->monitor_chandef to userspace.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 09d96a8f6c2c..808f5fcd1ced 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3285,13 +3285,19 @@ static int ieee80211_cfg_get_channel(struct wiphy *wiphy,
                                      struct cfg80211_chan_def *chandef)
 {
         struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
+        struct ieee80211_local *local = wiphy_priv(wiphy);
         struct ieee80211_chanctx_conf *chanctx_conf;
         int ret = -ENODATA;
 
         rcu_read_lock();
-        chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
-        if (chanctx_conf) {
-                *chandef = chanctx_conf->def;
+        if (local->use_chanctx) {
+                chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+                if (chanctx_conf) {
+                        *chandef = chanctx_conf->def;
+                        ret = 0;
+                }
+        } else if (local->open_count == local->monitors) {
+                *chandef = local->monitor_chandef;
                 ret = 0;
         }
         rcu_read_unlock();