====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc3-syzkaller-00257-gd863f0539b52 #0 Not tainted ------------------------------------------------------ syz-executor.3/7922 is trying to acquire lock: ffff88801e41f130 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1725 [inline] ffff88801e41f130 (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: ffffffff8e2e8428 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1790 [inline] ffffffff8e2e8428 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xd9/0x260 net/bluetooth/hci_conn.c:2427 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/0x1360 kernel/locking/mutex.c:747 hci_connect_cfm include/net/bluetooth/hci_core.h:1775 [inline] hci_remote_features_evt+0x49e/0xa20 net/bluetooth/hci_event.c:3768 hci_event_func net/bluetooth/hci_event.c:7482 [inline] hci_event_packet+0x956/0xfd0 net/bluetooth/hci_event.c:7534 hci_rx_work+0xaeb/0x1230 net/bluetooth/hci_core.c:4043 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #1 (&hdev->lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1360 kernel/locking/mutex.c:747 sco_sock_connect+0x1ea/0xa60 net/bluetooth/sco.c:593 __sys_connect_file+0x153/0x1a0 net/socket.c:1976 __sys_connect+0x165/0x1a0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __ia32_sys_connect+0x72/0xb0 net/socket.c:2000 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3470 lock_sock include/net/sock.h:1725 [inline] sco_conn_del+0x12c/0x2b0 net/bluetooth/sco.c:197 sco_disconn_cfm+0x75/0xb0 net/bluetooth/sco.c:1379 hci_disconn_cfm include/net/bluetooth/hci_core.h:1793 [inline] hci_conn_hash_flush+0x126/0x260 net/bluetooth/hci_conn.c:2427 hci_dev_close_sync+0x5fb/0x1200 net/bluetooth/hci_sync.c:4850 hci_dev_do_close+0x31/0x70 net/bluetooth/hci_core.c:554 hci_rfkill_set_block+0x161/0x1d0 net/bluetooth/hci_core.c:956 rfkill_set_block+0x1f9/0x540 net/rfkill/core.c:345 rfkill_fop_write+0x2c7/0x570 net/rfkill/core.c:1286 vfs_write+0x2db/0xdd0 fs/read_write.c:582 ksys_write+0x1ec/0x250 fs/read_write.c:637 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 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-executor.3/7922: #0: ffffffff8e4e61e8 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x160/0x570 net/rfkill/core.c:1278 #1: ffff888054f99028 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x29/0x70 net/bluetooth/hci_core.c:552 #2: ffff888054f98078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x306/0x1200 net/bluetooth/hci_sync.c:4837 #3: ffffffff8e2e8428 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1790 [inline] #3: ffffffff8e2e8428 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xd9/0x260 net/bluetooth/hci_conn.c:2427 stack backtrace: CPU: 3 PID: 7922 Comm: syz-executor.3 Not tainted 6.2.0-rc3-syzkaller-00257-gd863f0539b52 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3470 lock_sock include/net/sock.h:1725 [inline] sco_conn_del+0x12c/0x2b0 net/bluetooth/sco.c:197 sco_disconn_cfm+0x75/0xb0 net/bluetooth/sco.c:1379 hci_disconn_cfm include/net/bluetooth/hci_core.h:1793 [inline] hci_conn_hash_flush+0x126/0x260 net/bluetooth/hci_conn.c:2427 hci_dev_close_sync+0x5fb/0x1200 net/bluetooth/hci_sync.c:4850 hci_dev_do_close+0x31/0x70 net/bluetooth/hci_core.c:554 hci_rfkill_set_block+0x161/0x1d0 net/bluetooth/hci_core.c:956 rfkill_set_block+0x1f9/0x540 net/rfkill/core.c:345 rfkill_fop_write+0x2c7/0x570 net/rfkill/core.c:1286 vfs_write+0x2db/0xdd0 fs/read_write.c:582 ksys_write+0x1ec/0x250 fs/read_write.c:637 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f7f549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f7a5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000080 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi