From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
commit 81bc6d150ace6250503b825d9d0c10f7bbd24095 upstream.
When the target line contains an invalid device, delay_ctr() will call
delay_dtr() with NULL workqueue. Attempting to destroy the NULL
workqueue causes a crash.
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-delay.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -222,7 +222,8 @@ static void delay_dtr(struct dm_target *
{
struct delay_c *dc = ti->private;
- destroy_workqueue(dc->kdelayd_wq);
+ if (dc->kdelayd_wq)
+ destroy_workqueue(dc->kdelayd_wq);
dm_put_device(ti, dc->dev_read);
