======================================
| [  439.910033][   T12] vethhv-22: left promiscuous mode
| [  439.910215][   T12] br2: port 1(vethhv-22) entered disabled state
| [  439.944877][   T68] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN
| [  439.945068][   T68] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
[  439.945330][   T68] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  439.945427][   T68] Workqueue: ipv6_addrconf addrconf_dad_work
[  439.945531][   T68] RIP: 0010:mroute6_is_socket (net/ipv6/ip6mr.c:1686 (discriminator 4))
[  439.945619][   T68] Code: df 48 89 f9 48 c1 e9 03 80 3c 11 00 75 2f 48 8b 80 e8 10 00 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 30 48 89 f9 48 c1 e9 03 <80> 3c 11 00 75 1c 48 83 78 30 00 0f 95 c0 48 83 c4 08 c3 48 89 04
All code
========
   0:	df 48 89             	fisttps -0x77(%rax)
   3:	f9                   	stc
   4:	48 c1 e9 03          	shr    $0x3,%rcx
   8:	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1)
   c:	75 2f                	jne    0x3d
   e:	48 8b 80 e8 10 00 00 	mov    0x10e8(%rax),%rax
  15:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  1c:	fc ff df 
  1f:	48 8d 78 30          	lea    0x30(%rax),%rdi
  23:	48 89 f9             	mov    %rdi,%rcx
  26:	48 c1 e9 03          	shr    $0x3,%rcx
  2a:*	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1)		<-- trapping instruction
  2e:	75 1c                	jne    0x4c
  30:	48 83 78 30 00       	cmpq   $0x0,0x30(%rax)
  35:	0f 95 c0             	setne  %al
  38:	48 83 c4 08          	add    $0x8,%rsp
  3c:	c3                   	ret
  3d:	48                   	rex.W
  3e:	89                   	.byte 0x89
  3f:	04                   	.byte 0x4

Code starting with the faulting instruction
===========================================
   0:	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1)
   4:	75 1c                	jne    0x22
   6:	48 83 78 30 00       	cmpq   $0x0,0x30(%rax)
   b:	0f 95 c0             	setne  %al
   e:	48 83 c4 08          	add    $0x8,%rsp
  12:	c3                   	ret
  13:	48                   	rex.W
  14:	89                   	.byte 0x89
  15:	04                   	.byte 0x4
[  439.945888][   T68] RSP: 0018:ffa00000004976e0 EFLAGS: 00010216
[  439.945984][   T68] RAX: 0000000000000000 RBX: ff1100000be211c0 RCX: 0000000000000006
[  439.946095][   T68] RDX: dffffc0000000000 RSI: ff1100000be211c0 RDI: 0000000000000030
[  439.946208][   T68] RBP: ff11000008020200 R08: ffffffffaafb8550 R09: 1fe2200000a18935
[  439.946323][   T68] R10: ff11000005180828 R11: ff110000099dc0b0 R12: 1ff4000000092ee6
[  439.946445][   T68] R13: ff110000099dc000 R14: ff11000008cbd000 R15: ff11000005180810
[  439.946564][   T68] FS:  0000000000000000(0000) GS:ff110000be264000(0000) knlGS:0000000000000000
[  439.946701][   T68] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  439.946795][   T68] CR2: 00007fc4717ff240 CR3: 000000002f34f003 CR4: 0000000000771ef0
[  439.946910][   T68] PKRU: 55555554
[  439.946968][   T68] Call Trace:
[  439.947025][   T68]  <TASK>
[  439.947066][   T68]  ip6_finish_output2 (net/ipv6/ip6_output.c:84 (discriminator 3))
[  439.947143][   T68]  ? ip6_xmit (net/ipv6/ip6_output.c:61)
[  439.947225][   T68]  ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1))
[  439.947301][   T68]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5536)
[  439.947379][   T68]  ? ip6_mtu (./include/linux/rcupdate.h:322 (discriminator 2) ./include/linux/rcupdate.h:881 (discriminator 2) ./include/net/ip6_route.h:382 (discriminator 2) net/ipv6/route.c:3281 (discriminator 2))
[  439.947437][   T68]  ip6_finish_output (net/ipv6/ip6_output.c:208 net/ipv6/ip6_output.c:219)
[  439.947516][   T68]  ip6_output (./include/linux/netfilter.h:307 net/ipv6/ip6_output.c:246)
[  439.947572][   T68]  ? ip6_finish_output (net/ipv6/ip6_output.c:227)
[  439.947649][   T68]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5536)
[  439.947725][   T68]  ? xfrm_bundle_lookup.constprop.0 (net/xfrm/xfrm_policy.c:3177)
[  439.947818][   T68]  ? mark_held_locks (kernel/locking/lockdep.c:4325 (discriminator 1))
[  439.947894][   T68]  ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/softirq.c:455)
[  439.947968][   T68]  ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/softirq.c:455)
[  439.948045][   T68]  ? icmp6_dst_alloc (net/ipv6/route.c:3357 (discriminator 1))
[  439.948128][   T68]  mld_sendpack (./include/linux/netfilter.h:319 ./include/linux/netfilter.h:312 net/ipv6/mcast.c:1855)
[  439.948204][   T68]  ? nf_hook.constprop.0 (net/ipv4/ip_forward.c:66)
[  439.948276][   T68]  ipv6_mc_dad_complete (net/ipv6/mcast.c:2280)
[  439.948349][   T68]  ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/softirq.c:455)
[  439.948426][   T68]  addrconf_dad_completed (net/ipv6/addrconf.c:4347)
[  439.948498][   T68]  ? addrconf_rs_timer (net/ipv6/addrconf.c:4313)
[  439.948569][   T68]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5536)
[  439.948645][   T68]  ? __rwlock_init (kernel/locking/spinlock_debug.c:114)
[  439.948717][   T68]  ? mark_held_locks (kernel/locking/lockdep.c:4325 (discriminator 1))
[  439.948790][   T68]  ? addrconf_dad_work (net/ipv6/addrconf.c:4274)
[  439.948861][   T68]  addrconf_dad_work (net/ipv6/addrconf.c:4274)
[  439.948938][   T68]  ? addrconf_dad_begin (net/ipv6/addrconf.c:4181)
[  439.949010][   T68]  ? process_one_work (kernel/workqueue.c:3252 (discriminator 2))
[  439.949084][   T68]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  439.949159][   T68]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  439.949233][   T68]  ? lock_acquire (./include/trace/events/lock.h:24 (discriminator 24) kernel/locking/lockdep.c:5831 (discriminator 24))
[  439.949307][   T68]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  439.949381][   T68]  process_one_work (kernel/workqueue.c:3281)
[  439.949455][   T68]  ? pwq_dec_nr_in_flight (kernel/workqueue.c:3177)
[  439.949529][   T68]  ? lock_acquire.part.0 (kernel/locking/lockdep.c:470 (discriminator 2) kernel/locking/lockdep.c:5870 (discriminator 2))
[  439.949610][   T68]  ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1))
[  439.949689][   T68]  worker_thread (kernel/workqueue.c:3353 (discriminator 5) kernel/workqueue.c:3440 (discriminator 5))
[  439.949761][   T68]  ? rescuer_thread (kernel/workqueue.c:3386)
[  439.949836][   T68]  kthread (kernel/kthread.c:436)
[  439.949892][   T68]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 24))
[  439.949988][   T68]  ? kthread_affine_node (kernel/kthread.c:381)
[  439.950066][   T68]  ret_from_fork (arch/x86/kernel/process.c:164)
[  439.950143][   T68]  ? arch_exit_to_user_mode_prepare.isra.0 (arch/x86/entry/syscall_64.c:37)
[  439.950239][   T68]  ? __switch_to (./arch/x86/include/asm/cpufeature.h:101 (discriminator 1) arch/x86/kernel/process_64.c:377 (discriminator 1) arch/x86/kernel/process_64.c:665 (discriminator 1))
[  439.950312][   T68]  ? kthread_affine_node (kernel/kthread.c:381)


Finger prints:
mroute6_is_socket:ip6_finish_output2:ip6_finish_output:ip6_output:mld_sendpack