This is a note to let you know that I've just added the patch titled Bluetooth: initialize skb_queue_head at l2cap_chan_create() to the 5.12-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: bluetooth-initialize-skb_queue_head-at-l2cap_chan_cr.patch and it can be found in the queue-5.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 00070554cee5b024e4f582b5d0c465f8b0df0af8 Author: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Date: Mon Mar 22 07:52:07 2021 +0900 Bluetooth: initialize skb_queue_head at l2cap_chan_create() [ Upstream commit be8597239379f0f53c9710dd6ab551bbf535bec6 ] syzbot is hitting "INFO: trying to register non-static key." message [1], for "struct l2cap_chan"->tx_q.lock spinlock is not yet initialized when l2cap_chan_del() is called due to e.g. timeout. Since "struct l2cap_chan"->lock mutex is initialized at l2cap_chan_create() immediately after "struct l2cap_chan" is allocated using kzalloc(), let's as well initialize "struct l2cap_chan"->{tx_q,srej_q}.lock spinlocks there. [1] https://syzkaller.appspot.com/bug?extid=fadfba6a911f6bf71842 Reported-and-tested-by: syzbot <syzbot+fadfba6a911f6bf71842@xxxxxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index db6a4b2d0d77..53ddbee459b9 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -451,6 +451,8 @@ struct l2cap_chan *l2cap_chan_create(void) if (!chan) return NULL; + skb_queue_head_init(&chan->tx_q); + skb_queue_head_init(&chan->srej_q); mutex_init(&chan->lock); /* Set default lock nesting level */