From: Yang Yingliang yangyingliang@huawei.com
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@huawei.com Acked-by: Oleksij Rempel o.rempel@pengutronix.de Link: https://lore.kernel.org/all/20221027091237.2290111-1-yangyingliang@huawei.co... Cc: stable@vger.kernel.org [mkl: adjust subject] Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -342,10 +342,12 @@ 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,