From: Shang XiaoJing <shangxiaojing@xxxxxxxxxx>
commit 41f563ab3c33698bdfc3403c7c2e6c94e73681e4 upstream.
start_task() calls create_singlethread_workqueue() and not checked the
ret value, which may return NULL. And a null-ptr-deref may happen:
start_task()
create_singlethread_workqueue() # failed, led_wq is NULL
queue_delayed_work()
queue_delayed_work_on()
__queue_delayed_work() # warning here, but continue
__queue_work() # access wq->flags, null-ptr-deref
Check the ret value and return -ENOMEM if it is NULL.
Fixes: 3499495205a6 ("[PARISC] Use work queue in LED/LCD driver instead of tasklet.")
Signed-off-by: Shang XiaoJing <shangxiaojing@xxxxxxxxxx>
Signed-off-by: Helge Deller <deller@xxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/parisc/led.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/parisc/led.c
+++ b/drivers/parisc/led.c
@@ -141,6 +141,9 @@ static int start_task(void)
/* Create the work queue and queue the LED task */
led_wq = create_singlethread_workqueue("led_wq");
+ if (!led_wq)
+ return -ENOMEM;
+
queue_delayed_work(led_wq, &led_task, 0);
return 0;
