[PATCH v2 RESEND 2/2] Input: psmouse - Replace flush_workqueue() with disable_delayed_work_sync()

[Duoming Zhou]

The original code uses flush_workqueue() in psmouse_disconnect() to
ensure the completion of both resync_work and dev3_register_work.
Given that alps_disconnect() already uses disable_delayed_work_sync()
to cancel dev3_register_work, replacing flush_workqueue() with
disable_delayed_work_sync(&psmouse->resync_work) is more robust
and efficient.

Signed-off-by: Duoming Zhou <duoming@xxxxxxxxxx>
---
Changes in v2:
  - focus on the robustness and efficiency improvements of disable_delayed_work_sync(), not on the UAF aspect.

 drivers/input/mouse/psmouse-base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 77ea7da3b1c..eb41c553e80 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -1484,7 +1484,7 @@ static void psmouse_disconnect(struct serio *serio)
 
 	/* make sure we don't have a resync in progress */
 	mutex_unlock(&psmouse_mutex);
-	flush_workqueue(kpsmoused_wq);
+	disable_delayed_work_sync(&psmouse->resync_work);
 	mutex_lock(&psmouse_mutex);
 
 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
-- 
2.34.1