Warning: Permanently added '10.128.1.14' (ED25519) to the list of known hosts. executing program syzkaller login: [ 44.521495][ T4023] [ 44.522206][ T4023] ===================================== [ 44.523593][ T4023] WARNING: bad unlock balance detected! [ 44.525071][ T4023] 5.15.179-syzkaller #0 Not tainted [ 44.526440][ T4023] ------------------------------------- [ 44.527751][ T4023] kworker/u5:2/4023 is trying to release lock (&chan->lock) at: [ 44.529732][ T4023] [] l2cap_recv_frame+0xf60/0x6c28 [ 44.531417][ T4023] but there are no more locks to release! [ 44.532809][ T4023] [ 44.532809][ T4023] other info that might help us debug this: [ 44.534735][ T4023] 2 locks held by kworker/u5:2/4023: [ 44.536024][ T4023] #0: ffff0000ca831138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 [ 44.538651][ T4023] #1: ffff80001feb7c00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 [ 44.541577][ T4023] [ 44.541577][ T4023] stack backtrace: [ 44.543071][ T4023] CPU: 0 PID: 4023 Comm: kworker/u5:2 Not tainted 5.15.179-syzkaller #0 [ 44.545171][ T4023] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 [ 44.547748][ T4023] Workqueue: hci0 hci_rx_work [ 44.549020][ T4023] Call trace: [ 44.549885][ T4023] dump_backtrace+0x0/0x530 [ 44.551044][ T4023] show_stack+0x2c/0x3c [ 44.552119][ T4023] dump_stack_lvl+0x108/0x170 [ 44.553329][ T4023] dump_stack+0x1c/0x58 [ 44.554373][ T4023] print_unlock_imbalance_bug+0x250/0x2a4 [ 44.555923][ T4023] lock_release+0x4b8/0xa1c [ 44.557079][ T4023] __mutex_unlock_slowpath+0xe0/0x6d4 [ 44.558551][ T4023] mutex_unlock+0x8c/0xe0 [ 44.559729][ T4023] l2cap_recv_frame+0xf60/0x6c28 [ 44.561095][ T4023] l2cap_recv_acldata+0x4f4/0x163c [ 44.562502][ T4023] hci_rx_work+0x3a8/0x830 [ 44.563661][ T4023] process_one_work+0x790/0x11b8 [ 44.564992][ T4023] worker_thread+0x910/0x1034 [ 44.566234][ T4023] kthread+0x37c/0x45c [ 44.567256][ T4023] ret_from_fork+0x10/0x20