======================================
| [ 1151.118310][   T69] ==================================================================
| [ 1151.118820][ T69] BUG: KASAN: slab-use-after-free in vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
| [ 1151.119287][   T69] Read of size 8 at addr ffff888009418bd0 by task kworker/u8:1/69
| [ 1151.119729][   T69]
[ 1151.120253][   T69] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 1151.120900][   T69] Workqueue: netns cleanup_net
[ 1151.121243][   T69] Call Trace:
[ 1151.121439][   T69]  <TASK>
[ 1151.121653][ T69] dump_stack_lvl (lib/dump_stack.c:107) 
[ 1151.121889][ T69] print_address_description.constprop.0 (mm/kasan/report.c:378) 
[ 1151.122230][ T69] ? vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
[ 1151.122618][ T69] print_report (mm/kasan/report.c:489) 
[ 1151.122870][ T69] ? kasan_addr_to_slab (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 ./include/linux/page-flags.h:481 mm/kasan/../slab.h:206 mm/kasan/common.c:38) 
[ 1151.123123][ T69] kasan_report (mm/kasan/report.c:603) 
[ 1151.123383][ T69] ? vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
[ 1151.123823][ T69] vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
[ 1151.124194][ T69] ? __pfx_vlan_device_event (net/8021q/vlan.c:362) 8021q
[ 1151.124523][ T69] ? __pfx_vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4631) vxlan
[ 1151.124973][ T69] ? netconsole_netdev_event (drivers/net/netconsole.c:991) 
[ 1151.125289][ T69] notifier_call_chain (kernel/notifier.c:93) 
[ 1151.125677][ T69] unregister_netdevice_many_notify (net/core/dev.c:11095) 
[ 1151.126077][ T69] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2569 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3161 kernel/locking/mutex.c:81 kernel/locking/mutex.c:91) 
[ 1151.126338][ T69] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11035) 
[ 1151.126754][ T69] ? vrf_dellink (drivers/net/vrf.c:1708) vrf
[ 1151.127086][ T69] ? __pfx_unregister_netdevice_queue (net/core/dev.c:11019) 
[ 1151.127447][ T69] default_device_exit_batch (net/core/dev.c:11629) 
[ 1151.127868][ T69] ? __pfx_default_device_exit_batch (net/core/dev.c:11604) 
[ 1151.128212][ T69] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2569 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3161 kernel/locking/mutex.c:81 kernel/locking/mutex.c:91) 
[ 1151.128528][ T69] ? nexthop_net_exit_batch_rtnl (net/ipv4/nexthop.c:569 net/ipv4/nexthop.c:1918 net/ipv4/nexthop.c:2426 net/ipv4/nexthop.c:3754) 
[ 1151.128897][ T69] cleanup_net (net/core/net_namespace.c:636 (discriminator 3)) 
[ 1151.129184][ T69] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 1151.129503][ T69] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 1151.129790][ T69] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 1151.130129][ T69] ? process_one_work (kernel/workqueue.c:2609) 
[ 1151.130457][ T69] process_one_work (kernel/workqueue.c:2633) 
[ 1151.130709][ T69] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 1151.131005][ T69] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 1151.131340][ T69] ? assign_work (kernel/workqueue.c:1101) 
[ 1151.131624][ T69] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 1151.131858][ T69] ? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4300 kernel/locking/lockdep.c:4359) 
[ 1151.132240][ T69] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 1151.132561][ T69] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 1151.132823][ T69] kthread (kernel/kthread.c:388) 
[ 1151.133109][ T69] ? __pfx_kthread (kernel/kthread.c:341) 
[ 1151.133341][ T69] ret_from_fork (arch/x86/kernel/process.c:147) 
[ 1151.133603][ T69] ? __pfx_kthread (kernel/kthread.c:341) 
[ 1151.133853][ T69] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) 
| [ 1151.154427][   T69] ==================================================================
| [ 1151.155689][   T69] Disabling lock debugging due to kernel taint
| [ 1151.156061][   T69] general protection fault, probably for non-canonical address 0xdffffc002000007d: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [ 1151.156734][   T69] KASAN: probably user-memory-access in range [0x00000001000003e8-0x00000001000003ef]
[ 1151.157774][   T69] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 1151.158451][   T69] Workqueue: netns cleanup_net
[ 1151.158759][ T69] RIP: 0010:vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
[ 1151.159153][ T69] Code: 00 00 00 48 b9 00 00 00 00 00 fc ff df 49 89 c0 48 89 44 24 08 49 c1 e8 03 4d 8d 24 08 eb 2c 48 8d 53 30 48 89 d0 48 c1 e8 03 <80> 3c 08 00 0f 85 e0 00 00 00 48 8b 43 30 49 89 dd 48 83 e8 30 49
All code
========
   0:	00 00                	add    %al,(%rax)
   2:	00 48 b9             	add    %cl,-0x47(%rax)
   5:	00 00                	add    %al,(%rax)
   7:	00 00                	add    %al,(%rax)
   9:	00 fc                	add    %bh,%ah
   b:	ff                   	(bad)
   c:	df 49 89             	fisttps -0x77(%rcx)
   f:	c0 48 89 44          	rorb   $0x44,-0x77(%rax)
  13:	24 08                	and    $0x8,%al
  15:	49 c1 e8 03          	shr    $0x3,%r8
  19:	4d 8d 24 08          	lea    (%r8,%rcx,1),%r12
  1d:	eb 2c                	jmp    0x4b
  1f:	48 8d 53 30          	lea    0x30(%rbx),%rdx
  23:	48 89 d0             	mov    %rdx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
  2a:*	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1)		<-- trapping instruction
  2e:	0f 85 e0 00 00 00    	jne    0x114
  34:	48 8b 43 30          	mov    0x30(%rbx),%rax
  38:	49 89 dd             	mov    %rbx,%r13
  3b:	48 83 e8 30          	sub    $0x30,%rax
  3f:	49                   	rex.WB

Code starting with the faulting instruction
===========================================
   0:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1)
   4:	0f 85 e0 00 00 00    	jne    0xea
   a:	48 8b 43 30          	mov    0x30(%rbx),%rax
   e:	49 89 dd             	mov    %rbx,%r13
  11:	48 83 e8 30          	sub    $0x30,%rax
  15:	49                   	rex.WB
[ 1151.160216][   T69] RSP: 0018:ffffc900004ef980 EFLAGS: 00010206
[ 1151.160564][   T69] RAX: 000000002000007d RBX: 00000001000003b8 RCX: dffffc0000000000
[ 1151.160989][   T69] RDX: 00000001000003e8 RSI: 0000000000000004 RDI: ffff888009418c24
[ 1151.161414][   T69] RBP: 1ffff9200009df33 R08: 1ffff11000c8b21a R09: ffffc900004ef9b8
[ 1151.161865][   T69] R10: ffffffff8973ca07 R11: 205d393654202020 R12: ffffed1000c8b21a
[ 1151.162267][   T69] R13: ffff888009418ba0 R14: ffff888003864000 R15: ffff888006459000
[ 1151.162655][   T69] FS:  0000000000000000(0000) GS:ffff888035a00000(0000) knlGS:0000000000000000
[ 1151.163112][   T69] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1151.163455][   T69] CR2: 00007fa6f6e7e008 CR3: 000000000adba004 CR4: 0000000000770ef0
[ 1151.163848][   T69] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1151.164240][   T69] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1151.164630][   T69] PKRU: 55555554
[ 1151.164809][   T69] Call Trace:
[ 1151.164990][   T69]  <TASK>
[ 1151.165138][ T69] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 1151.165356][ T69] ? exc_general_protection (arch/x86/kernel/traps.c:701 arch/x86/kernel/traps.c:643) 
[ 1151.165648][ T69] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:564) 
[ 1151.165951][ T69] ? vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4613 drivers/net/vxlan/vxlan_core.c:4636) vxlan
[ 1151.166308][ T69] ? __pfx_vxlan_netdevice_event (drivers/net/vxlan/vxlan_core.c:4631) vxlan
[ 1151.166643][ T69] ? netconsole_netdev_event (drivers/net/netconsole.c:991) 
[ 1151.166929][ T69] notifier_call_chain (kernel/notifier.c:93) 
[ 1151.167185][ T69] unregister_netdevice_many_notify (net/core/dev.c:11095) 
[ 1151.167538][ T69] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2569 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3161 kernel/locking/mutex.c:81 kernel/locking/mutex.c:91) 
[ 1151.167792][ T69] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11035) 
[ 1151.168210][ T69] ? vrf_dellink (drivers/net/vrf.c:1708) vrf
[ 1151.168494][ T69] ? __pfx_unregister_netdevice_queue (net/core/dev.c:11019) 
[ 1151.168805][ T69] default_device_exit_batch (net/core/dev.c:11629) 
[ 1151.169112][ T69] ? __pfx_default_device_exit_batch (net/core/dev.c:11604) 
[ 1151.169501][ T69] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2569 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3161 kernel/locking/mutex.c:81 kernel/locking/mutex.c:91) 
[ 1151.169740][ T69] ? nexthop_net_exit_batch_rtnl (net/ipv4/nexthop.c:569 net/ipv4/nexthop.c:1918 net/ipv4/nexthop.c:2426 net/ipv4/nexthop.c:3754) 
[ 1151.170035][ T69] cleanup_net (net/core/net_namespace.c:636 (discriminator 3)) 
[ 1151.170257][ T69] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 1151.170545][ T69] ? __pfx_cleanup_net (net/core/net_namespace.c:581) 
[ 1151.170794][ T69] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5725) 
[ 1151.171033][ T69] ? process_one_work (kernel/workqueue.c:2609) 
[ 1151.171302][ T69] process_one_work (kernel/workqueue.c:2633) 
[ 1151.171551][ T69] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 1151.171779][ T69] ? __pfx_process_one_work (kernel/workqueue.c:2542) 
[ 1151.172054][ T69] ? assign_work (kernel/workqueue.c:1101) 
[ 1151.172288][ T69] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) 
[ 1151.172529][ T69] ? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4300 kernel/locking/lockdep.c:4359) 
[ 1151.172868][ T69] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 1151.173135][ T69] ? __pfx_worker_thread (kernel/workqueue.c:2733) 
[ 1151.173401][ T69] kthread (kernel/kthread.c:388) 
[ 1151.173628][ T69] ? __pfx_kthread (kernel/kthread.c:341) 
[ 1151.173866][ T69] ret_from_fork (arch/x86/kernel/process.c:147) 
[ 1151.174089][ T69] ? __pfx_kthread (kernel/kthread.c:341) 


Finger prints:
dump_stack_lvl:print_report:kasan_report:vxlan_netdevice_event
vxlan_netdevice_event:notifier_call_chain:unregister_netdevice_many_notify:default_device_exit_batch