This is a note to let you know that I've just added the patch titled can: j1939: transport: j1939_session_skb_drop_old(): spin_unlock_irqrestore() before kfree_skb() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: can-j1939-transport-j1939_session_skb_drop_old-spin_unlock_irqrestore-before-kfree_skb.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c3c06c61890da80494bb196f75d89b791adda87f Mon Sep 17 00:00:00 2001 From: Yang Yingliang <yangyingliang@xxxxxxxxxx> Date: Thu, 27 Oct 2022 17:12:37 +0800 Subject: can: j1939: transport: j1939_session_skb_drop_old(): spin_unlock_irqrestore() before kfree_skb() 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 @@ -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, Patches currently in stable-queue which might be from yangyingliang@xxxxxxxxxx are queue-5.15/can-j1939-transport-j1939_session_skb_drop_old-spin_unlock_irqrestore-before-kfree_skb.patch