------------[ cut here ]------------ workqueue: cannot queue hci_conn_timeout on wq hci4 WARNING: kernel/workqueue.c:2297 at __queue_work+0xcee/0x1270 kernel/workqueue.c:2296, CPU#3: syz.6.2855/16064 Modules linked in: CPU: 3 UID: 0 PID: 16064 Comm: syz.6.2855 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__queue_work+0xcf2/0x1270 kernel/workqueue.c:2296 Code: 00 00 00 fc ff df 49 8d 94 24 70 01 00 00 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 3d 05 00 00 48 8d 3d 72 04 0b 0f 48 8b 75 18 <67> 48 0f b9 3a 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 RSP: 0018:ffffc90004827698 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff110046e614b RDX: ffff8880577a8970 RSI: ffffffff8a826380 RDI: ffffffff90da1e80 RBP: ffff888023730a40 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880577a8800 R13: ffff88802578a540 R14: ffff888023730a88 R15: ffff888023730a48 FS: 0000000000000000(0000) GS:ffff8880d6683000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f78db57cff8 CR3: 0000000025336000 CR4: 0000000000352ef0 Call Trace: __queue_delayed_work+0x357/0x450 kernel/workqueue.c:2560 queue_delayed_work_on+0x180/0x1e0 kernel/workqueue.c:2612 queue_delayed_work include/linux/workqueue.h:713 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1712 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1686 [inline] l2cap_chan_del+0x649/0x930 net/bluetooth/l2cap_core.c:674 l2cap_chan_close+0x3b0/0xa70 net/bluetooth/l2cap_core.c:847 l2cap_sock_shutdown+0x3cc/0x1160 net/bluetooth/l2cap_sock.c:1414 l2cap_sock_release+0x8d/0x280 net/bluetooth/l2cap_sock.c:1461 __sock_release+0xb3/0x260 net/socket.c:722 sock_close+0x1c/0x30 net/socket.c:1514 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2af0 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 get_signal+0x20ff/0x2210 kernel/signal.c:3037 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x98/0x670 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8e7695d68e Code: Unable to access opcode bytes at 0x7f8e7695d664. RSP: 002b:00007f8e778d8f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f8e778d96c0 RCX: 00007f8e7695d68e RDX: 00007f8e778d8fb0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f8e76a32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8e76c16128 R14: 00007f8e76c16090 R15: 00007fff14022b78 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 fc add %bh,%ah 4: ff lcall (bad) 5: df 49 8d fisttps -0x73(%rcx) 8: 94 xchg %eax,%esp 9: 24 70 and $0x70,%al b: 01 00 add %eax,(%rax) d: 00 48 89 add %cl,-0x77(%rax) 10: f9 stc 11: 48 c1 e9 03 shr $0x3,%rcx 15: 80 3c 01 00 cmpb $0x0,(%rcx,%rax,1) 19: 0f 85 3d 05 00 00 jne 0x55c 1f: 48 8d 3d 72 04 0b 0f lea 0xf0b0472(%rip),%rdi # 0xf0b0498 26: 48 8b 75 18 mov 0x18(%rbp),%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 36: fc ff df 39: 48 89 ea mov %rbp,%rdx 3c: 48 c1 ea 03 shr $0x3,%rdx