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ODEBUG: free active (active state 0) object: ffff88802c876490 object type: timer_list hint: rose_t0timer_expiry+0x0/0x150 include/linux/skbuff.h:2927
WARNING: CPU: 1 PID: 16716 at lib/debugobjects.c:612 debug_print_object+0x1a2/0x2b0 lib/debugobjects.c:612
Modules linked in:
CPU: 1 UID: 0 PID: 16716 Comm: kworker/u32:7 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:debug_print_object+0x1a2/0x2b0 lib/debugobjects.c:612
Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 54 41 56 48 8b 14 dd a0 81 f0 8b 4c 89 e6 48 c7 c7 20 76 f0 8b e8 bf b3 ce fc 90 <0f> 0b 90 90 58 83 05 d6 da d5 0b 01 48 83 c4 18 5b 5d 41 5c 41 5d
RSP: 0018:ffffc900006a0a18 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff817b1cd8
RDX: ffff888012b5a480 RSI: ffffffff817b1ce5 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8bf07cc0
R13: ffffffff8b9021e0 R14: ffffffff8a4da210 R15: ffffc900006a0b18
FS:  0000000000000000(0000) GS:ffff8880d6b06000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555cf8808 CR3: 0000000038524000 CR4: 0000000000352ef0
DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline]
 debug_check_no_obj_freed+0x4b7/0x600 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2474 [inline]
 slab_free mm/slub.c:6642 [inline]
 kfree+0x291/0x6d0 mm/slub.c:6849
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183
 call_timer_fn+0x19a/0x620 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers+0x6ef/0x960 kernel/time/timer.c:2372
 __run_timer_base kernel/time/timer.c:2384 [inline]
 __run_timer_base kernel/time/timer.c:2376 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2393
 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2403
 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_unregister_key+0xe9/0x140 kernel/locking/lockdep.c:6616
Code: 48 89 ef e8 b9 e5 ff ff 48 83 2d 39 01 29 14 01 89 c3 e8 da ee ff ff 9c 58 f6 c4 02 75 52 41 f7 c4 00 02 00 00 74 01 fb 84 db <75> 1b 5b 5d 41 5c e9 9c 79 0a 00 8b 05 ba d9 e9 0e 31 db 85 c0 74
RSP: 0018:ffffc900070b77a8 EFLAGS: 00000246
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8db1b325 RDI: ffffffff8bf070c0
RBP: ffffffff97286a88 R08: 0000000000007f3b R09: ffffffff95c26896
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246
R13: ffff888039b46000 R14: ffff888039b464c8 R15: 0000000000000008
 __qdisc_destroy+0x11a/0x4d0 net/sched/sch_generic.c:1086
 qdisc_put+0xab/0xe0 net/sched/sch_generic.c:1112
 shutdown_scheduler_queue+0xa5/0x160 net/sched/sch_generic.c:1165
 netdev_for_each_tx_queue include/linux/netdevice.h:2664 [inline]
 dev_shutdown+0xb8/0x430 net/sched/sch_generic.c:1497
 unregister_netdevice_many_notify+0xb12/0x25c0 net/core/dev.c:12272
 unregister_netdevice_many net/core/dev.c:12347 [inline]
 default_device_exit_batch+0x853/0xaf0 net/core/dev.c:12851
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x363/0xab0 net/core/net_namespace.c:252
 cleanup_net+0x41b/0x8b0 net/core/net_namespace.c:695
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	e8 b9 e5 ff ff       	call   0xffffe5c1
   8:	48 83 2d 39 01 29 14 	subq   $0x1,0x14290139(%rip)        # 0x14290149
   f:	01
  10:	89 c3                	mov    %eax,%ebx
  12:	e8 da ee ff ff       	call   0xffffeef1
  17:	9c                   	pushf
  18:	58                   	pop    %rax
  19:	f6 c4 02             	test   $0x2,%ah
  1c:	75 52                	jne    0x70
  1e:	41 f7 c4 00 02 00 00 	test   $0x200,%r12d
  25:	74 01                	je     0x28
  27:	fb                   	sti
  28:	84 db                	test   %bl,%bl
* 2a:	75 1b                	jne    0x47 <-- trapping instruction
  2c:	5b                   	pop    %rbx
  2d:	5d                   	pop    %rbp
  2e:	41 5c                	pop    %r12
  30:	e9 9c 79 0a 00       	jmp    0xa79d1
  35:	8b 05 ba d9 e9 0e    	mov    0xee9d9ba(%rip),%eax        # 0xee9d9f5
  3b:	31 db                	xor    %ebx,%ebx
  3d:	85 c0                	test   %eax,%eax
  3f:	74                   	.byte 0x74