1 files changed, 19 insertions, 0 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index ecb57b0bf74a..5ad66a83ef7f 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -238,6 +238,9 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
         enum ieee80211_band band;
         int i, ielen, n_chans;
 
+        if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
+                return false;
+
         do {
                 if (local->hw_scan_band == IEEE80211_NUM_BANDS)
                         return false;
@@ -939,7 +942,23 @@ void ieee80211_scan_cancel(struct ieee80211_local *local)
         if (!local->scan_req)
                 goto out;
 
+        /*
+         * We have a scan running and the driver already reported completion,
+         * but the worker hasn't run yet or is stuck on the mutex - mark it as
+         * cancelled.
+         */
+        if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
+            test_bit(SCAN_COMPLETED, &local->scanning)) {
+                set_bit(SCAN_HW_CANCELLED, &local->scanning);
+                goto out;
+        }
+
         if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
+                /*
+                 * Make sure that __ieee80211_scan_completed doesn't trigger a
+                 * scan on another band.
+                 */
+                set_bit(SCAN_HW_CANCELLED, &local->scanning);
                 if (local->ops->cancel_hw_scan)
                         drv_cancel_hw_scan(local,
                                 rcu_dereference_protected(local->scan_sdata,