Cancel delayed scheduled scan when wpa_supplicant cleans up

Because a delayed scheduled scan will access the members of struct
wpa_supplicant which is freed and this can result in a crash,
wpa_supplicant needs to cancel delayed scheduled scan during cleanups.

Signed-hostap: Chengyi Zhao <chengyix.zhao@gmail.com>

wpa_supplicant/scan.c

@@ -1229,6 +1229,23 @@ void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 }
 
 
+/**
+ * wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
+ * @wpa_s: Pointer to wpa_supplicant data
+ *
+ * This function is used to stop a delayed scheduled scan.
+ */
+void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
+{
+	if (!wpa_s->sched_scan_supported)
+		return;
+
+	wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
+	eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
+			     wpa_s, NULL);
+}
+
+
 /**
  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
  * @wpa_s: Pointer to wpa_supplicant data

wpa_supplicant/scan.h

@@ -15,6 +15,7 @@ int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 				      int sec, int usec);
 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s);
 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s);
+void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s);
 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s);
 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
 				    int scanning);

wpa_supplicant/wpa_supplicant.c

@@ -421,6 +421,7 @@ static void wpa_supplicant_cleanup(struct wpa_supplicant *wpa_s)
 
 	wpa_bss_deinit(wpa_s);
 
+	wpa_supplicant_cancel_delayed_sched_scan(wpa_s);
 	wpa_supplicant_cancel_scan(wpa_s);
 	wpa_supplicant_cancel_auth_timeout(wpa_s);
 	eloop_cancel_timeout(wpa_supplicant_stop_countermeasures, wpa_s, NULL);