ODEBUG: free active (active state 0) object type: timer_list hint: resync_tnc+0x0/0x3c0 drivers/net/hamradio/6pack.c:839
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
------------[ cut here ]------------
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
WARNING: CPU: 1 PID: 9380 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
CPU: 1 PID: 9380 Comm: syz-executor.4 Not tainted 4.14.277-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
 __warn.cold+0x20/0x44 kernel/panic.c:547
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
 report_bug+0x208/0x250 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready
batman_adv: batadv0: Interface activated: batadv_slave_1
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff88805ad0f968 EFLAGS: 00010086
RAX: 0000000000000057 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff81443120 RDI: ffffed100b5a1f23
RBP: ffffffff878b78c0 R08: 0000000000000057 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880a9a62640 R12: ffffffff83f92780
R13: 0000000000000000 R14: ffff8880a597e540 R15: ffff8880ab92b038
 __debug_check_no_obj_freed lib/debugobjects.c:747 [inline]
 debug_check_no_obj_freed+0x3b7/0x680 lib/debugobjects.c:776
 kfree+0xb9/0x250 mm/slab.c:3814
 kvfree+0x45/0x50 mm/util.c:416
 device_release+0x15f/0x1a0 drivers/base/core.c:848
 kobject_cleanup lib/kobject.c:646 [inline]
 kobject_release lib/kobject.c:675 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put+0x251/0x550 lib/kobject.c:692
 netdev_run_todo+0x747/0xad0 net/core/dev.c:7969
 sixpack_close+0xd3/0x180 drivers/net/hamradio/6pack.c:688
 tty_ldisc_close+0x8c/0xc0 drivers/tty/tty_ldisc.c:505
 tty_set_ldisc+0x1b3/0x5d0 drivers/tty/tty_ldisc.c:600
 tiocsetd drivers/tty/tty_io.c:2351 [inline]
 tty_ioctl+0xa2a/0x1430 drivers/tty/tty_io.c:2595
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f4f131c50e9
RSP: 002b:00007f4f11b19168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4f132d8030 RCX: 00007f4f131c50e9
RDX: 0000000020000000 RSI: 0000000000005423 RDI: 0000000000000004
RBP: 00007f4f1321f08d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe16bbccff R14: 00007f4f11b19300 R15: 0000000000022000

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