[PATCH] station: check for roam timeout before rearming

[James Prestwood <prestwoj@gmail.com>]

A user reported a crash which was due to the roam trigger timeout
being overwritten, followed by a disconnect. Post-disconnect the
timer would fire and result in a crash. Its not clear exactly where
the overwrite was happening but upon code inspection it could
happen in the following scenario:

1. Beacon loss event, start roam timeout
2. Signal low event, no check if timeout is running and the timeout
   gets overwritten.

The reported crash actually didn't appear to be from the above
scenario but something else, so now all instances where the timer
is rearmed we also check if there is already a timer set.
---
 src/station.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/station.c b/src/station.c
index 30a1232a..e188aed4 100644
--- a/src/station.c
+++ b/src/station.c
@@ -2221,7 +2221,7 @@ static void station_roamed(struct station *station)
 	 * Schedule another roaming attempt in case the signal continues to
 	 * remain low. A subsequent high signal notification will cancel it.
 	 */
-	if (station->signal_low)
+	if (station->signal_low && L_WARN_ON(!station->roam_trigger_timeout))
 		station_roam_timeout_rearm(station, roam_retry_interval);
 
 	if (station->netconfig)
@@ -2260,7 +2260,7 @@ static void station_roam_retry(struct station *station)
 	station->roam_scan_full = false;
 	station->ap_directed_roaming = false;
 
-	if (station->signal_low)
+	if (station->signal_low && !station->roam_trigger_timeout)
 		station_roam_timeout_rearm(station, roam_retry_interval);
 }
 
@@ -3202,6 +3202,9 @@ static void station_low_rssi(struct station *station)
 	if (station_cannot_roam(station))
 		return;
 
+	if (station->roam_trigger_timeout)
+		return;
+
 	/* Set a 5-second initial timeout */
 	station_roam_timeout_rearm(station, 5);
 }
-- 
2.34.1