ODEBUG: free active (active state 0) object type: timer_list hint: rfcomm_dlc_timeout+0x0/0x60 include/linux/list.h:64
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3307 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3307 Comm: syz-executor.4 Not tainted 4.14.139 #35
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x138/0x19c lib/dump_stack.c:53
 panic+0x1f2/0x426 kernel/panic.c:182
 __warn.cold+0x2f/0x36 kernel/panic.c:546
 report_bug+0x216/0x254 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff8880313dfaa8 EFLAGS: 00010086
RAX: 000000000000005e RBX: 0000000000000003 RCX: 0000000000000000
RDX: 000000000002b1eb RSI: ffffffff814b2ab5 RDI: ffffed100627bf4b
RBP: ffff8880313dfad0 R08: 000000000000005e R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802d40e180 R12: ffffffff866cc0e0
R13: ffffffff85829cc0 R14: 0000000000000000 R15: ffff8880787122e8
 __debug_check_no_obj_freed lib/debugobjects.c:747 [inline]
 debug_check_no_obj_freed+0x3f5/0x7b7 lib/debugobjects.c:776
 kfree+0xbd/0x270 mm/slab.c:3814
 rfcomm_dlc_free+0x20/0x30 net/bluetooth/rfcomm/core.c:328
 rfcomm_dlc_put include/net/bluetooth/rfcomm.h:258 [inline]
 __rfcomm_create_dev net/bluetooth/rfcomm/tty.c:417 [inline]
 rfcomm_create_dev net/bluetooth/rfcomm/tty.c:486 [inline]
 rfcomm_dev_ioctl+0x1590/0x18b0 net/bluetooth/rfcomm/tty.c:588
 rfcomm_sock_ioctl+0x82/0xa0 net/bluetooth/rfcomm/sock.c:902
 sock_do_ioctl+0x64/0xb0 net/socket.c:974
 sock_ioctl+0x2a6/0x470 net/socket.c:1071
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459829
RSP: 002b:00007fd7078bcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000020000100 RSI: 00000000400452c8 RDI: 0000000000000004
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd7078bd6d4
R13: 00000000004c1f8e R14: 00000000004d5358 R15: 00000000ffffffff

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