From: Yang Yingliang <yangyingliang@xxxxxxxxxx> commit c3c06c61890da80494bb196f75d89b791adda87f upstream. It is not allowed to call kfree_skb() from hardware interrupt context or with interrupts being disabled. The skb is unlinked from the queue, so it can be freed after spin_unlock_irqrestore(). Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> Acked-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/all/20221027091237.2290111-1-yangyingliang@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx [mkl: adjust subject] Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/can/j1939/transport.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/can/j1939/transport.c +++ b/net/can/j1939/transport.c @@ -338,10 +338,12 @@ static void j1939_session_skb_drop_old(s __skb_unlink(do_skb, &session->skb_queue); /* drop ref taken in j1939_session_skb_queue() */ skb_unref(do_skb); + spin_unlock_irqrestore(&session->skb_queue.lock, flags); kfree_skb(do_skb); + } else { + spin_unlock_irqrestore(&session->skb_queue.lock, flags); } - spin_unlock_irqrestore(&session->skb_queue.lock, flags); } void j1939_session_skb_queue(struct j1939_session *session,