From: Mikulas Patocka <[email protected]> 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 <[email protected]> Cc: [email protected] Signed-off-by: Mike Snitzer <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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);
