4 files changed, 37 insertions, 10 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index ff45c3e1abff..4ab2c49423dc 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5550,6 +5550,14 @@ const struct ieee80211_reg_rule *freq_reg_info(struct wiphy *wiphy,
 const char *reg_initiator_name(enum nl80211_reg_initiator initiator);
 
 /**
+ * regulatory_pre_cac_allowed - check if pre-CAC allowed in the current regdom
+ * @wiphy: wiphy for which pre-CAC capability is checked.
+ *
+ * Pre-CAC is allowed only in some regdomains (notable ETSI).
+ */
+bool regulatory_pre_cac_allowed(struct wiphy *wiphy);
+
+/**
  * DOC: Internal regulatory db functions
  *
  */
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index adf94ba1ed77..4d31d9688dc2 100644
--- 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)) {
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 420c4207ab59..446c76d44e65 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -3883,6 +3883,7 @@ bool regulatory_pre_cac_allowed(struct wiphy *wiphy)
 
         return pre_cac_allowed;
 }
+EXPORT_SYMBOL(regulatory_pre_cac_allowed);
 
 void regulatory_propagate_dfs_state(struct wiphy *wiphy,
                                     struct cfg80211_chan_def *chandef,
diff --git a/net/wireless/reg.h b/net/wireless/reg.h
index 504133d76de4..dc8f689bd469 100644
--- a/net/wireless/reg.h
+++ b/net/wireless/reg.h
@@ -156,14 +156,6 @@ bool regulatory_indoor_allowed(void);
 #define REG_PRE_CAC_EXPIRY_GRACE_MS 2000
 
 /**
- * regulatory_pre_cac_allowed - if pre-CAC allowed in the current dfs domain
- * @wiphy: wiphy for which pre-CAC capability is checked.
-
- * Pre-CAC is allowed only in ETSI domain.
- */
-bool regulatory_pre_cac_allowed(struct wiphy *wiphy);
-
-/**
  * regulatory_propagate_dfs_state - Propagate DFS channel state to other wiphys
  * @wiphy - wiphy on which radar is detected and the event will be propagated
  *      to other available wiphys having the same DFS domain