======================================
| [ 4584.114649][    C1] ==================================================================
| [ 4584.114939][ C1] BUG: KASAN: null-ptr-deref in sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
| [ 4584.115144][    C1] Read of size 8 at addr 0000000000000008 by task swapper/1/0
| [ 4584.115337][    C1]
[ 4584.115609][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 4584.115896][    C1] Call Trace:
[ 4584.115997][    C1]  <IRQ>
[ 4584.116066][ C1] dump_stack_lvl (lib/dump_stack.c:117) 
[ 4584.116207][ C1] kasan_report (mm/kasan/report.c:603) 
[ 4584.116308][ C1] ? sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
[ 4584.116472][ C1] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 4584.116605][ C1] sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
[ 4584.116734][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 4584.116832][ C1] ip6_rcv_core (./include/linux/skbuff.h:3202 net/ipv6/ip6_input.c:291) 
[ 4584.116963][ C1] ipv6_rcv (net/ipv6/ip6_input.c:307) 
[ 4584.117063][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4584.117197][ C1] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 4584.117329][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.117463][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4584.117593][ C1] __netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4584.117755][ C1] ? __pfx___netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4584.117919][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.118071][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 4584.118205][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.118338][ C1] process_backlog (./include/linux/rcupdate.h:810 net/core/dev.c:6048) 
[ 4584.118469][ C1] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 4584.118600][ C1] ? rebalance_domains (./include/linux/rcupdate.h:339 ./include/linux/rcupdate.h:814 kernel/sched/fair.c:11753) 
[ 4584.118731][ C1] __napi_poll.constprop.0 (net/core/dev.c:6701) 
[ 4584.118863][ C1] net_rx_action (net/core/dev.c:6770 net/core/dev.c:6886) 
[ 4584.118995][ C1] ? __pfx_net_rx_action (net/core/dev.c:6850) 
[ 4584.119125][ C1] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1026) 
[ 4584.119254][ C1] ? spin_bug (./include/linux/pid.h:232 kernel/locking/spinlock_debug.c:64 kernel/locking/spinlock_debug.c:78) 
[ 4584.119356][ C1] ? __pfx_rebalance_domains (kernel/sched/fair.c:11684) 
[ 4584.119489][ C1] __do_softirq (kernel/softirq.c:554) 
[ 4584.119624][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 4584.119724][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 4584.119855][    C1]  </IRQ>
[ 4584.119922][    C1]  <TASK>
[ 4584.119989][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 4584.120153][ C1] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/kernel/process.c:743) 
[ 4584.120291][ C1] Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 cc 32 00 fb f4 <fa> c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
All code
========
   0:	4c 01 c7             	add    %r8,%rdi
   3:	4c 29 c2             	sub    %r8,%rdx
   6:	e9 72 ff ff ff       	jmp    0xffffffffffffff7d
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d f3 cc 32 00 	verw   0x32ccf3(%rip)        # 0x32cd1b
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	fa                   	cli		<-- trapping instruction
  2b:	c3                   	ret
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  37:	00 00 00 00 
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	fa                   	cli
   1:	c3                   	ret
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   5:	cc                   	int3
   6:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
   d:	00 00 00 00 
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[ 4584.120753][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 4584.120921][    C1] RAX: 000000000295df95 RBX: 1ffff92000029fc1 RCX: ffffffff88334e85
[ 4584.121119][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff85aac0e4
[ 4584.121319][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1709c
[ 4584.121510][    C1] R10: ffff8880360b84e3 R11: ffff8880360ad9b0 R12: 0000000000000000
[ 4584.121704][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 4584.121897][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 4584.122026][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4584.122156][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 4584.122288][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4584.122417][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 4584.122546][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 4584.122677][ C1] do_idle (kernel/sched/idle.c:332) 
[ 4584.122776][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 4584.122906][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 4584.123037][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:231) 
[ 4584.123168][ C1] common_startup_64 (arch/x86/kernel/head_64.S:421) 
| [ 4584.123402][    C1] ==================================================================
| [ 4584.123592][    C1] Disabling lock debugging due to kernel taint
| [ 4584.123777][    C1] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [ 4584.124057][    C1] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 4584.124469][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 4584.124748][ C1] RIP: 0010:sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
[ 4584.124911][ C1] Code: 00 4c 8b bb a0 01 00 00 be 08 00 00 00 4d 8d 77 08 4c 89 f7 e8 e0 0e 8b fe 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 fe 00 00 00 49 8b 47 08 a8 04 0f 85 dc fe ff ff
All code
========
   0:	00 4c 8b bb          	add    %cl,-0x45(%rbx,%rcx,4)
   4:	a0 01 00 00 be 08 00 	movabs 0x8be000001,%al
   b:	00 00 
   d:	4d 8d 77 08          	lea    0x8(%r15),%r14
  11:	4c 89 f7             	mov    %r14,%rdi
  14:	e8 e0 0e 8b fe       	call   0xfffffffffe8b0ef9
  19:	4c 89 f2             	mov    %r14,%rdx
  1c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  23:	fc ff df 
  26:	48 c1 ea 03          	shr    $0x3,%rdx
  2a:*	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)		<-- trapping instruction
  2e:	0f 85 fe 00 00 00    	jne    0x132
  34:	49 8b 47 08          	mov    0x8(%r15),%rax
  38:	a8 04                	test   $0x4,%al
  3a:	0f 85 dc fe ff ff    	jne    0xffffffffffffff1c

Code starting with the faulting instruction
===========================================
   0:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   4:	0f 85 fe 00 00 00    	jne    0x108
   a:	49 8b 47 08          	mov    0x8(%r15),%rax
   e:	a8 04                	test   $0x4,%al
  10:	0f 85 dc fe ff ff    	jne    0xfffffffffffffef2
[ 4584.125360][    C1] RSP: 0018:ffffc900001d8b28 EFLAGS: 00010202
[ 4584.125522][    C1] RAX: dffffc0000000000 RBX: ffff88800af50040 RCX: ffffffff8599564a
[ 4584.125711][    C1] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff8aefda00
[ 4584.125899][    C1] RBP: ffff88800af500a0 R08: 0000000000000001 R09: fffffbfff15dfb40
[ 4584.126089][    C1] R10: ffffffff8aefda07 R11: 205d314320202020 R12: 0000000000000000
[ 4584.126281][    C1] R13: ffff88800af501c0 R14: 0000000000000008 R15: 0000000000000000
[ 4584.126469][    C1] FS:  0000000000000000(0000) GS:ffff888036080000(0000) knlGS:0000000000000000
[ 4584.126688][    C1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4584.126847][    C1] CR2: 00007f64d7d44258 CR3: 0000000014538004 CR4: 0000000000770ef0
[ 4584.127040][    C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4584.127228][    C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 4584.127415][    C1] PKRU: 55555554
[ 4584.127510][    C1] Call Trace:
[ 4584.127608][    C1]  <IRQ>
[ 4584.127674][ C1] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 4584.127770][ C1] ? exc_general_protection (arch/x86/kernel/traps.c:702 arch/x86/kernel/traps.c:644) 
[ 4584.127899][ C1] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 4584.128037][ C1] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:555) 
[ 4584.128135][ C1] ? sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
[ 4584.128292][ C1] ? sock_def_write_space_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3397) 
[ 4584.128449][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 4584.128548][ C1] ip6_rcv_core (./include/linux/skbuff.h:3202 net/ipv6/ip6_input.c:291) 
[ 4584.128676][ C1] ipv6_rcv (net/ipv6/ip6_input.c:307) 
[ 4584.128773][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4584.128901][ C1] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 4584.129031][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.129158][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4584.129282][ C1] __netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4584.129441][ C1] ? __pfx___netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4584.129599][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.129726][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 4584.129854][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4584.129981][ C1] process_backlog (./include/linux/rcupdate.h:810 net/core/dev.c:6048) 
[ 4584.130108][ C1] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 4584.130237][ C1] ? rebalance_domains (./include/linux/rcupdate.h:339 ./include/linux/rcupdate.h:814 kernel/sched/fair.c:11753) 
[ 4584.130364][ C1] __napi_poll.constprop.0 (net/core/dev.c:6701) 
[ 4584.130493][ C1] net_rx_action (net/core/dev.c:6770 net/core/dev.c:6886) 
[ 4584.130622][ C1] ? __pfx_net_rx_action (net/core/dev.c:6850) 
[ 4584.130748][ C1] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1026) 
[ 4584.130874][ C1] ? spin_bug (./include/linux/pid.h:232 kernel/locking/spinlock_debug.c:64 kernel/locking/spinlock_debug.c:78) 
[ 4584.130970][ C1] ? __pfx_rebalance_domains (kernel/sched/fair.c:11684) 
[ 4584.131099][ C1] __do_softirq (kernel/softirq.c:554) 
[ 4584.131231][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 4584.131326][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 4584.131453][    C1]  </IRQ>
[ 4584.131519][    C1]  <TASK>
[ 4584.131583][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 4584.131740][ C1] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/kernel/process.c:743) 
[ 4584.131873][ C1] Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 cc 32 00 fb f4 <fa> c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
All code
========
   0:	4c 01 c7             	add    %r8,%rdi
   3:	4c 29 c2             	sub    %r8,%rdx
   6:	e9 72 ff ff ff       	jmp    0xffffffffffffff7d
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d f3 cc 32 00 	verw   0x32ccf3(%rip)        # 0x32cd1b
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	fa                   	cli		<-- trapping instruction
  2b:	c3                   	ret
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  37:	00 00 00 00 
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	fa                   	cli
   1:	c3                   	ret
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   5:	cc                   	int3
   6:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
   d:	00 00 00 00 
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[ 4584.132322][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 4584.132481][    C1] RAX: 000000000295df95 RBX: 1ffff92000029fc1 RCX: ffffffff88334e85
[ 4584.132672][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff85aac0e4
[ 4584.132860][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1709c
[ 4584.133050][    C1] R10: ffff8880360b84e3 R11: ffff8880360ad9b0 R12: 0000000000000000
[ 4584.133239][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 4584.133427][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 4584.133553][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4584.133680][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 4584.133807][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4584.133934][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 4584.134063][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 4584.134191][ C1] do_idle (kernel/sched/idle.c:332) 
[ 4584.134287][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 4584.134414][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 4584.134541][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:231) 


Finger prints:
dump_stack_lvl:kasan_report:kasan_check_range:sock_def_write_space_wfree
sock_def_write_space_wfree:sock_wfree:ip6_rcv_core:ipv6_rcv