======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc3-syzkaller-00073-geabcdba3ad40 #0 Not tainted
------------------------------------------------------
kworker/u33:3/5938 is trying to acquire lock:
ffff88804fd42258 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1617 [inline]
ffff88804fd42258 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_conn_ready net/bluetooth/sco.c:1341 [inline]
ffff88804fd42258 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_connect_cfm+0x3bc/0xc00 net/bluetooth/sco.c:1415

but task is already holding lock:
ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: sco_conn_ready net/bluetooth/sco.c:1328 [inline]
ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: sco_connect_cfm+0x29f/0xc00 net/bluetooth/sco.c:1415

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&conn->lock#2){+.+.}-{3:3}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       sco_chan_add net/bluetooth/sco.c:292 [inline]
       sco_connect net/bluetooth/sco.c:348 [inline]
       sco_sock_connect+0x3b2/0xcc0 net/bluetooth/sco.c:648
       __sys_connect_file+0x13e/0x1a0 net/socket.c:2055
       __sys_connect+0x14f/0x170 net/socket.c:2074
       __do_sys_connect net/socket.c:2080 [inline]
       __se_sys_connect net/socket.c:2077 [inline]
       __x64_sys_connect+0x72/0xb0 net/socket.c:2077
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
       lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622
       lock_sock include/net/sock.h:1617 [inline]
       sco_conn_ready net/bluetooth/sco.c:1341 [inline]
       sco_connect_cfm+0x3bc/0xc00 net/bluetooth/sco.c:1415
       hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]
       hci_sync_conn_complete_evt+0x421/0xa80 net/bluetooth/hci_event.c:5014
       hci_event_func net/bluetooth/hci_event.c:7473 [inline]
       hci_event_packet+0x9eb/0x1180 net/bluetooth/hci_event.c:7525
       hci_rx_work+0x2c5/0x16b0 net/bluetooth/hci_core.c:4035
       process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
       process_scheduled_works kernel/workqueue.c:3310 [inline]
       worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
       kthread+0x2c1/0x3a0 kernel/kthread.c:389
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&conn->lock#2);
                               lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);
                               lock(&conn->lock#2);
  lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

4 locks held by kworker/u33:3/5938:
 #0: ffff88802a531148 ((wq_completion)hci2#2){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3204
 #1: ffffc90003e0fd80 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
 #2: ffff888023f80078 (&hdev->lock){+.+.}-{4:4}, at: hci_sync_conn_complete_evt+0x199/0xa80 net/bluetooth/hci_event.c:4931
 #3: ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #3: ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: sco_conn_ready net/bluetooth/sco.c:1328 [inline]
 #3: ffff888031d9a420 (&conn->lock#2){+.+.}-{3:3}, at: sco_connect_cfm+0x29f/0xc00 net/bluetooth/sco.c:1415

stack backtrace:
CPU: 3 UID: 0 PID: 5938 Comm: kworker/u33:3 Not tainted 6.13.0-rc3-syzkaller-00073-geabcdba3ad40 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci2 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622
 lock_sock include/net/sock.h:1617 [inline]
 sco_conn_ready net/bluetooth/sco.c:1341 [inline]
 sco_connect_cfm+0x3bc/0xc00 net/bluetooth/sco.c:1415
 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]
 hci_sync_conn_complete_evt+0x421/0xa80 net/bluetooth/hci_event.c:5014
 hci_event_func net/bluetooth/hci_event.c:7473 [inline]
 hci_event_packet+0x9eb/0x1180 net/bluetooth/hci_event.c:7525
 hci_rx_work+0x2c5/0x16b0 net/bluetooth/hci_core.c:4035
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
BUG: sleeping function called from invalid context at net/core/sock.c:3624
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5938, name: kworker/u33:3
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 3 UID: 0 PID: 5938 Comm: kworker/u33:3 Not tainted 6.13.0-rc3-syzkaller-00073-geabcdba3ad40 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci2 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
 __might_resched+0x3c0/0x5e0 kernel/sched/core.c:8758
 lock_sock_nested+0x4b/0xf0 net/core/sock.c:3624
 lock_sock include/net/sock.h:1617 [inline]
 sco_conn_ready net/bluetooth/sco.c:1341 [inline]
 sco_connect_cfm+0x3bc/0xc00 net/bluetooth/sco.c:1415
 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]
 hci_sync_conn_complete_evt+0x421/0xa80 net/bluetooth/hci_event.c:5014
 hci_event_func net/bluetooth/hci_event.c:7473 [inline]
 hci_event_packet+0x9eb/0x1180 net/bluetooth/hci_event.c:7525
 hci_rx_work+0x2c5/0x16b0 net/bluetooth/hci_core.c:4035
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Bluetooth: hci2: command tx timeout