------------[ cut here ]------------ workqueue: cannot queue hci_conn_timeout on wq hci4 WARNING: kernel/workqueue.c:2251 at 0x0, CPU#0: syz.0.852/9314 Modules linked in: CPU: 0 UID: 0 PID: 9314 Comm: syz.0.852 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__queue_work+0xca1/0x10e0 kernel/workqueue.c:2250 Code: 78 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 0c 04 00 00 48 8d 3d 63 3a 06 0f 48 8b 75 18 <67> 48 0f b9 3a e9 90 f7 ff ff e8 e0 31 3a 00 90 0f 0b 90 e9 15 f6 RSP: 0018:ffffc9000dadf7d0 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff1100f26b94b RDX: ffff8880282c8178 RSI: ffffffff8a6e1e50 RDI: ffffffff908aece0 RBP: ffff88807935ca40 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: ffff888034310b30 R12: 0000000000000000 R13: ffff8880282c8000 R14: ffff88807935ca88 R15: ffff8880282c8000 FS: 00007fb3d67676c0(0000) GS:ffff888124909000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007c0ff000 CR4: 00000000003526f0 Call Trace: __queue_delayed_work+0x35b/0x460 kernel/workqueue.c:2503 queue_delayed_work_on+0x1b5/0x200 kernel/workqueue.c:2555 queue_delayed_work include/linux/workqueue.h:684 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1710 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1684 [inline] l2cap_chan_del+0x5a0/0x940 net/bluetooth/l2cap_core.c:672 l2cap_chan_close+0xfe/0xa80 net/bluetooth/l2cap_core.c:845 l2cap_sock_shutdown+0x3cc/0x11b0 net/bluetooth/l2cap_sock.c:1384 l2cap_sock_release+0x8d/0x280 net/bluetooth/l2cap_sock.c:1431 __sock_release+0xb3/0x270 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x402/0xb70 fs/file_table.c:468 task_work_run+0x150/0x240 kernel/task_work.c:233 get_signal+0x1d0/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb3d598f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb3d6767038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffffc RBX: 00007fb3d5be6180 RCX: 00007fb3d598f749 RDX: 000000000000000e RSI: 0000200000000080 RDI: 0000000000000008 RBP: 00007fb3d5a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb3d5be6218 R14: 00007fb3d5be6180 R15: 00007ffc7c9c6d98 ---------------- Code disassembly (best guess): 0: 78 01 js 0x3 2: 00 00 add %al,(%rax) 4: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax b: fc ff df e: 48 89 f9 mov %rdi,%rcx 11: 48 c1 e9 03 shr $0x3,%rcx 15: 80 3c 01 00 cmpb $0x0,(%rcx,%rax,1) 19: 0f 85 0c 04 00 00 jne 0x42b 1f: 48 8d 3d 63 3a 06 0f lea 0xf063a63(%rip),%rdi # 0xf063a89 26: 48 8b 75 18 mov 0x18(%rbp),%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: e9 90 f7 ff ff jmp 0xfffff7c4 34: e8 e0 31 3a 00 call 0x3a3219 39: 90 nop 3a: 0f 0b ud2 3c: 90 nop 3d: e9 .byte 0xe9 3e: 15 .byte 0x15 3f: f6 .byte 0xf6