====================================================== WARNING: possible circular locking dependency detected 5.15.173-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u5:1/4024 is trying to acquire lock: ffff0000e77f1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] ffff0000e77f1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_conn_ready net/bluetooth/sco.c:1110 [inline] ffff0000e77f1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1201 but task is already holding lock: ffff800016de65a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline] ffff800016de65a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (hci_cb_list_lock){+.+.}-{3:3}: __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743 hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline] hci_remote_features_evt+0x480/0x940 net/bluetooth/hci_event.c:3352 hci_event_packet+0x5ec/0x12b4 net/bluetooth/hci_event.c:6421 hci_rx_work+0x1c0/0x7c4 net/bluetooth/hci_core.c:5155 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 -> #1 (&hdev->lock){+.+.}-{3:3}: __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743 sco_sock_connect+0x170/0x848 net/bluetooth/sco.c:591 __sys_connect_file net/socket.c:1923 [inline] __sys_connect+0x268/0x290 net/socket.c:1940 __do_sys_connect net/socket.c:1950 [inline] __se_sys_connect net/socket.c:1947 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:1947 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 lock_sock_nested+0xec/0x1ec net/core/sock.c:3250 lock_sock include/net/sock.h:1678 [inline] sco_conn_ready net/bluetooth/sco.c:1110 [inline] sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1201 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline] hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551 hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483 hci_rx_work+0x1c0/0x7c4 net/bluetooth/hci_core.c:5155 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 other info that might help us debug this: Chain exists of: sk_lock-AF_BLUETOOTH-BTPROTO_SCO --> &hdev->lock --> hci_cb_list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(hci_cb_list_lock); lock(&hdev->lock); lock(hci_cb_list_lock); lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO); *** DEADLOCK *** 4 locks held by kworker/u5:1/4024: #0: ffff0000e53ef138 ((wq_completion)hci4#2){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff80001fee7c00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000c9ecc078 (&hdev->lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0xb4/0x8c0 net/bluetooth/hci_event.c:4471 #3: ffff800016de65a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1502 [inline] #3: ffff800016de65a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_sync_conn_complete_evt+0x404/0x8c0 net/bluetooth/hci_event.c:4551 stack backtrace: CPU: 0 PID: 4024 Comm: kworker/u5:1 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci4 hci_rx_work Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 lock_sock_nested+0xec/0x1ec net/core/sock.c:3250 lock_sock include/net/sock.h:1678 [inline] sco_conn_ready net/bluetooth/sco.c:1110 [inline] sco_connect_cfm+0x140/0x908 net/bluetooth/sco.c:1201 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline] hci_sync_conn_complete_evt+0x468/0x8c0 net/bluetooth/hci_event.c:4551 hci_event_packet+0x8e0/0x12b4 net/bluetooth/hci_event.c:6483 hci_rx_work+0x1c0/0x7c4 net/bluetooth/hci_core.c:5155 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870