RBP: 00000000004bfab0 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6894 at lib/debugobjects.c:290 debug_print_object.cold.13+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 6894 Comm: kworker/u4:5 Not tainted 4.14.154-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xf7/0x13b lib/dump_stack.c:58
 panic+0x1b0/0x358 kernel/panic.c:183
 __warn.cold.8+0x25/0x2c kernel/panic.c:547
 report_bug+0x1a4/0x1f3 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 do_error_trap+0x1bd/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.13+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff88807e6ef7b8 EFLAGS: 00010086
RAX: 0000000000000061 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000061 RSI: 0000000000000001 RDI: ffffed100fcddeee
RBP: ffff88807e6ef7e0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88807e6ef298 R11: dffffc0000000000 R12: ffffffff868ca220
R13: ffffffff813c3d80 R14: 0000000000000000 R15: ffff8880a9115400
 __debug_check_no_obj_freed lib/debugobjects.c:747 [inline]
 debug_check_no_obj_freed+0x506/0x930 lib/debugobjects.c:776
 kfree+0xbd/0x270 mm/slab.c:3814
 kvfree+0x2c/0x30 mm/util.c:416
 netdev_freemem+0x47/0x60 net/core/dev.c:8038
 netdev_release+0x6a/0x80 net/core/net-sysfs.c:1497
 device_release+0x134/0x170 drivers/base/core.c:825
 kobject_cleanup lib/kobject.c:646 [inline]
 kobject_release lib/kobject.c:675 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put.cold.11+0x22a/0x2aa lib/kobject.c:692
 netdev_run_todo+0x49e/0x6d0 net/core/dev.c:7943
 rtnl_unlock+0x9/0x10 net/core/rtnetlink.c:106
 default_device_exit_batch+0x2e1/0x3b0 net/core/dev.c:8729
 ops_exit_list.isra.7+0xd3/0x120 net/core/net_namespace.c:145
 cleanup_net+0x39d/0x800 net/core/net_namespace.c:484
 process_one_work+0x79e/0x16c0 kernel/workqueue.c:2114
 worker_thread+0xcc/0xee0 kernel/workqueue.c:2248
 kthread+0x338/0x400 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

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