====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc4-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor229/3645 is trying to acquire lock: ffff88807835d130 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1712 [inline] ffff88807835d130 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: sco_conn_del+0x12c/0x2b0 net/bluetooth/sco.c:197 but task is already holding lock: ffffffff8d9cfb68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1776 [inline] ffffffff8d9cfb68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xd5/0x260 net/bluetooth/hci_conn.c:2366 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 kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 hci_connect_cfm+0x26/0x140 include/net/bluetooth/hci_core.h:1761 hci_remote_features_evt+0x494/0x900 net/bluetooth/hci_event.c:3757 hci_event_func net/bluetooth/hci_event.c:7443 [inline] hci_event_packet+0x952/0xfd0 net/bluetooth/hci_event.c:7495 hci_rx_work+0xae7/0x1230 net/bluetooth/hci_core.c:4007 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 -> #1 (&hdev->lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 sco_sock_connect+0x1e6/0xa70 net/bluetooth/sco.c:593 __sys_connect_file+0x14f/0x190 net/socket.c:1976 __sys_connect+0x161/0x190 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:2000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 lock_sock_nested+0x36/0xf0 net/core/sock.c:3393 lock_sock include/net/sock.h:1712 [inline] sco_conn_del+0x12c/0x2b0 net/bluetooth/sco.c:197 sco_disconn_cfm+0x71/0xb0 net/bluetooth/sco.c:1379 hci_disconn_cfm include/net/bluetooth/hci_core.h:1779 [inline] hci_conn_hash_flush+0x122/0x260 net/bluetooth/hci_conn.c:2366 hci_dev_close_sync+0x55d/0x1130 net/bluetooth/hci_sync.c:4476 hci_dev_do_close+0x2d/0x70 net/bluetooth/hci_core.c:554 hci_rfkill_set_block+0x15d/0x1c0 net/bluetooth/hci_core.c:947 rfkill_set_block+0x1f9/0x540 net/rfkill/core.c:345 rfkill_fop_write+0x2c3/0x570 net/rfkill/core.c:1286 vfs_write+0x2d7/0xdd0 fs/read_write.c:576 ksys_write+0x1e8/0x250 fs/read_write.c:631 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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 syz-executor229/3645: #0: ffffffff8dbc1ec8 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x15c/0x570 net/rfkill/core.c:1278 #1: ffff888020568fd0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x25/0x70 net/bluetooth/hci_core.c:552 #2: ffff888020568078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x268/0x1130 net/bluetooth/hci_sync.c:4463 #3: ffffffff8d9cfb68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1776 [inline] #3: ffffffff8d9cfb68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xd5/0x260 net/bluetooth/hci_conn.c:2366 stack backtrace: CPU: 0 PID: 3645 Comm: syz-executor229 Not tainted 6.0.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 lock_sock_nested+0x36/0xf0 net/core/sock.c:3393 lock_sock include/net/sock.h:1712 [inline] sco_conn_del+0x12c/0x2b0 net/bluetooth/sco.c:197 sco_disconn_cfm+0x71/0xb0 net/bluetooth/sco.c:1379 hci_disconn_cfm include/net/bluetooth/hci_core.h:1779 [inline] hci_conn_hash_flush+0x122/0x260 net/bluetooth/hci_conn.c:2366 hci_dev_close_sync+0x55d/0x1130 net/bluetooth/hci_sync.c:4476 hci_dev_do_close+0x2d/0x70 net/bluetooth/hci_core.c:554 hci_rfkill_set_block+0x15d/0x1c0 net/bluetooth/hci_core.c:947 rfkill_set_block+0x1f9/0x540 net/rfkill/core.c:345 rfkill_fop_write+0x2c3/0x570 net/rfkill/core.c:1286 vfs_write+0x2d7/0xdd0 fs/read_write.c:576 ksys_write+0x1e8/0x250 fs/read_write.c:631 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f0ebc349499 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe75b17ba8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0ebc349499 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000150 R09: 0000000000000150 R10: 0000000000000150 R11: 0000000000000246 R12: 00005555565882b8 R13: 0000000000000011 R14: 00007ffe75b17c10 R15: 0000000000000000