======================================
| [  101.810683][   T12] ==================================================================
| [  101.811056][   T12] BUG: KASAN: slab-use-after-free in kobject_put (lib/kobject.c:733)
| [  101.811387][   T12] Read of size 1 at addr ffff88800f4b46ac by task kworker/u16:0/12
| [  101.811692][   T12]
[  101.811858][   T12] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  101.811862][   T12] Workqueue: netns cleanup_net
[  101.811878][   T12] Call Trace:
[  101.811884][   T12]  <TASK>
[  101.811889][   T12]  dump_stack_lvl (lib/dump_stack.c:123)
[  101.811902][   T12]  print_address_description.constprop.0 (mm/kasan/report.c:379)
[  101.811917][   T12]  ? kobject_put (lib/kobject.c:733)
[  101.811923][   T12]  print_report (mm/kasan/report.c:483)
[  101.811927][   T12]  ? kobject_put (lib/kobject.c:733)
[  101.811932][   T12]  ? kasan_addr_to_slab (./include/linux/mm.h:1245 mm/kasan/../slab.h:191 mm/kasan/common.c:47)
[  101.811938][   T12]  ? kobject_put (lib/kobject.c:733)
[  101.811943][   T12]  kasan_report (mm/kasan/report.c:597)
[  101.811949][   T12]  ? kobject_put (lib/kobject.c:733)
[  101.811959][   T12]  kobject_put (lib/kobject.c:733)
[  101.811964][   T12]  netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670)
[  101.811973][   T12]  ? irqentry_exit (kernel/entry/common.c:215)
[  101.811984][   T12]  ? dev_ingress_queue_create (net/core/dev.c:12299)
[  101.811989][   T12]  ? generic_xdp_install (net/core/dev.c:11630)
[  101.811997][   T12]  ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3189 kernel/locking/mutex.h:47 kernel/locking/mutex.c:67)
[  101.812007][   T12]  ops_undo_list (net/core/net_namespace.c:190 net/core/net_namespace.c:248)
[  101.812012][   T12]  ? netns_get (net/core/net_namespace.c:223)
[  101.812015][   T12]  ? cleanup_net (./include/linux/list.h:191 net/core/net_namespace.c:693)
[  101.812020][   T12]  cleanup_net (net/core/net_namespace.c:698)
[  101.812024][   T12]  ? net_passive_dec (net/core/net_namespace.c:660)
[  101.812028][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[  101.812038][   T12]  process_one_work (kernel/workqueue.c:3268)
[  101.812047][   T12]  ? pwq_dec_nr_in_flight (kernel/workqueue.c:3165)
[  101.812053][   T12]  ? assign_work (kernel/workqueue.c:1206)
[  101.812057][   T12]  worker_thread (kernel/workqueue.c:3340 kernel/workqueue.c:3427)
[  101.812062][   T12]  ? rescuer_thread (kernel/workqueue.c:3373)
[  101.812066][   T12]  kthread (kernel/kthread.c:463)
[  101.812072][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[  101.812074][   T12]  ? ret_from_fork (arch/x86/kernel/process.c:157)
[  101.812081][   T12]  ? __lock_release (kernel/locking/lockdep.c:5536)
[  101.812088][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[  101.812092][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[  101.812095][   T12]  ret_from_fork (arch/x86/kernel/process.c:164)
[  101.812100][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[  101.812103][   T12]  ret_from_fork_asm (arch/x86/entry/entry_64.S:255)
| [  101.833487][   T12] refcount_t: underflow; use-after-free.
| [  101.833685][   T12] WARNING: CPU: 0 PID: 12 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
| [  101.834036][   T12] Modules linked in: act_gact cls_flower vxlan ip6_udp_tunnel udp_tunnel bridge stp llc sch_ingress vrf veth
| [  101.834890][   T12] Tainted: [B]=BAD_PAGE
[  101.835031][   T12] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  101.835266][   T12] Workqueue: netns cleanup_net
[  101.835462][   T12] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
[  101.835702][   T12] Code: 7d 93 02 80 fb 01 0f 87 bb 99 d9 fe 83 e3 01 0f 85 51 ff ff ff c6 05 a8 7d 93 02 01 90 48 c7 c7 60 8d a5 9b e8 32 bf 18 ff 90 <0f> 0b 90 90 e9 33 ff ff ff 48 89 df e8 b0 63 a1 ff e9 ba fe ff ff
All code
========
   0:	7d 93                	jge    0xffffffffffffff95
   2:	02 80 fb 01 0f 87    	add    -0x78f0fe05(%rax),%al
   8:	bb 99 d9 fe 83       	mov    $0x83fed999,%ebx
   d:	e3 01                	jrcxz  0x10
   f:	0f 85 51 ff ff ff    	jne    0xffffffffffffff66
  15:	c6 05 a8 7d 93 02 01 	movb   $0x1,0x2937da8(%rip)        # 0x2937dc4
  1c:	90                   	nop
  1d:	48 c7 c7 60 8d a5 9b 	mov    $0xffffffff9ba58d60,%rdi
  24:	e8 32 bf 18 ff       	call   0xffffffffff18bf5b
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	e9 33 ff ff ff       	jmp    0xffffffffffffff66
  33:	48 89 df             	mov    %rbx,%rdi
  36:	e8 b0 63 a1 ff       	call   0xffffffffffa163eb
  3b:	e9 ba fe ff ff       	jmp    0xfffffffffffffefa

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	e9 33 ff ff ff       	jmp    0xffffffffffffff3c
   9:	48 89 df             	mov    %rbx,%rdi
   c:	e8 b0 63 a1 ff       	call   0xffffffffffa163c1
  11:	e9 ba fe ff ff       	jmp    0xfffffffffffffed0
[  101.836343][   T12] RSP: 0018:ffffc900000c7a08 EFLAGS: 00010282
[  101.836578][   T12] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  101.836848][   T12] RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000001
[  101.837117][   T12] RBP: 0000000000000003 R08: 0000000000000000 R09: fffffbfff387e134
[  101.837391][   T12] R10: 0000000000000003 R11: ffffc900000c7580 R12: 0000000000000001
[  101.837677][   T12] R13: dffffc0000000000 R14: dead000000000122 R15: dead000000000100
[  101.837948][   T12] FS:  0000000000000000(0000) GS:ffff8880989f2000(0000) knlGS:0000000000000000
[  101.838266][   T12] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  101.838485][   T12] CR2: 00007ffe575507c8 CR3: 0000000005075006 CR4: 0000000000772ef0
[  101.838747][   T12] PKRU: 55555554
[  101.838897][   T12] Call Trace:
[  101.839035][   T12]  <TASK>
[  101.839135][   T12]  netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670)
[  101.839335][   T12]  ? irqentry_exit (kernel/entry/common.c:215)
[  101.839519][   T12]  ? dev_ingress_queue_create (net/core/dev.c:12299)
[  101.839695][   T12]  ? generic_xdp_install (net/core/dev.c:11630)
[  101.839876][   T12]  ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3189 kernel/locking/mutex.h:47 kernel/locking/mutex.c:67)
[  101.840054][   T12]  ops_undo_list (net/core/net_namespace.c:190 net/core/net_namespace.c:248)
[  101.840251][   T12]  ? netns_get (net/core/net_namespace.c:223)
[  101.840420][   T12]  ? cleanup_net (./include/linux/list.h:191 net/core/net_namespace.c:693)
[  101.840696][   T12]  cleanup_net (net/core/net_namespace.c:698)
[  101.840871][   T12]  ? net_passive_dec (net/core/net_namespace.c:660)
[  101.841051][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[  101.841319][   T12]  process_one_work (kernel/workqueue.c:3268)
[  101.841498][   T12]  ? pwq_dec_nr_in_flight (kernel/workqueue.c:3165)
[  101.841667][   T12]  ? assign_work (kernel/workqueue.c:1206)
[  101.841926][   T12]  worker_thread (kernel/workqueue.c:3340 kernel/workqueue.c:3427)
[  101.842102][   T12]  ? rescuer_thread (kernel/workqueue.c:3373)
[  101.842276][   T12]  kthread (kernel/kthread.c:463)
[  101.842407][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[  101.842576][   T12]  ? ret_from_fork (arch/x86/kernel/process.c:157)
[  101.842746][   T12]  ? __lock_release (kernel/locking/lockdep.c:5536)
[  101.842915][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[  101.843084][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[  101.843263][   T12]  ret_from_fork (arch/x86/kernel/process.c:164)
[  101.843614][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)


Finger prints:
refcount_warn_saturate:netdev_run_todo:ops_undo_list:cleanup_net:process_one_work
print_report:kasan_report:kobject_put:netdev_run_todo:ops_undo_list