======================================
| [ 4631.470268][    C1] ==================================================================
| [ 4631.470590][ 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) 
| [ 4631.470795][    C1] Read of size 8 at addr 0000000000000008 by task swapper/1/0
| [ 4631.470989][    C1]
[ 4631.471253][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 4631.471538][    C1] Call Trace:
[ 4631.471638][    C1]  <IRQ>
[ 4631.471706][ C1] dump_stack_lvl (lib/dump_stack.c:117) 
[ 4631.471844][ C1] kasan_report (mm/kasan/report.c:603) 
[ 4631.471944][ 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) 
[ 4631.472110][ C1] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 4631.472240][ 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) 
[ 4631.472368][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 4631.472465][ C1] ip6_rcv_core (./include/linux/skbuff.h:3202 net/ipv6/ip6_input.c:291) 
[ 4631.472593][ C1] ipv6_rcv (net/ipv6/ip6_input.c:307) 
[ 4631.472690][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4631.472817][ C1] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 4631.472945][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.473073][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4631.473197][ C1] __netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4631.473356][ C1] ? __pfx___netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4631.473514][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.473642][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 4631.473769][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.473901][ C1] process_backlog (./include/linux/rcupdate.h:810 net/core/dev.c:6048) 
[ 4631.474029][ C1] __napi_poll.constprop.0 (net/core/dev.c:6701) 
[ 4631.474162][ C1] net_rx_action (net/core/dev.c:6770 net/core/dev.c:6886) 
[ 4631.474294][ C1] ? __pfx_net_rx_action (net/core/dev.c:6850) 
[ 4631.474426][ C1] __do_softirq (kernel/softirq.c:554) 
[ 4631.474558][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 4631.474658][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 4631.474789][    C1]  </IRQ>
[ 4631.474855][    C1]  <TASK>
[ 4631.474919][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 4631.475086][ 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) 
[ 4631.475219][ 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 d3 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 d3 cc 32 00 	verw   0x32ccd3(%rip)        # 0x32ccfb
  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
[ 4631.475670][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 4631.475833][    C1] RAX: 0000000002b04353 RBX: 1ffff92000029fc1 RCX: ffffffff9e734ea5
[ 4631.476022][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9beac0e4
[ 4631.476208][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1709c
[ 4631.476397][    C1] R10: ffff8880360b84e3 R11: ffff8880360ad9b0 R12: 0000000000000000
[ 4631.476584][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 4631.476774][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 4631.476899][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4631.477028][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 4631.477154][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4631.477280][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 4631.477412][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 4631.477541][ C1] do_idle (kernel/sched/idle.c:332) 
[ 4631.477637][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 4631.477764][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 4631.477892][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:231) 
[ 4631.478019][ C1] common_startup_64 (arch/x86/kernel/head_64.S:421) 
| [ 4631.478244][    C1] ==================================================================
| [ 4631.478430][    C1] Disabling lock debugging due to kernel taint
| [ 4631.478613][    C1] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [ 4631.478886][    C1] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 4631.479279][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 4631.479556][ 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) 
[ 4631.479714][ 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
[ 4631.480150][    C1] RSP: 0018:ffffc900001d8b28 EFLAGS: 00010202
[ 4631.480310][    C1] RAX: dffffc0000000000 RBX: ffff88800aed99c0 RCX: ffffffff9bd9564a
[ 4631.480494][    C1] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffa12fda00
[ 4631.480676][    C1] RBP: ffff88800aed9a20 R08: 0000000000000001 R09: fffffbfff425fb40
[ 4631.480860][    C1] R10: ffffffffa12fda07 R11: 205d314320202020 R12: 0000000000000000
[ 4631.481043][    C1] R13: ffff88800aed9b40 R14: 0000000000000008 R15: 0000000000000000
[ 4631.481230][    C1] FS:  0000000000000000(0000) GS:ffff888036080000(0000) knlGS:0000000000000000
[ 4631.481443][    C1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4631.481598][    C1] CR2: 000055fdcf2c2898 CR3: 0000000002742006 CR4: 0000000000770ef0
[ 4631.481784][    C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4631.481972][    C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 4631.482155][    C1] PKRU: 55555554
[ 4631.482249][    C1] Call Trace:
[ 4631.482344][    C1]  <IRQ>
[ 4631.482409][ C1] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 4631.482506][ C1] ? exc_general_protection (arch/x86/kernel/traps.c:702 arch/x86/kernel/traps.c:644) 
[ 4631.482633][ C1] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 4631.482757][ C1] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:555) 
[ 4631.482852][ 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) 
[ 4631.483010][ 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) 
[ 4631.483163][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 4631.483259][ C1] ip6_rcv_core (./include/linux/skbuff.h:3202 net/ipv6/ip6_input.c:291) 
[ 4631.483383][ C1] ipv6_rcv (net/ipv6/ip6_input.c:307) 
[ 4631.483476][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4631.483600][ C1] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 4631.483723][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.483850][ C1] ? __pfx_ipv6_rcv (net/ipv6/ip6_input.c:304) 
[ 4631.483978][ C1] __netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4631.484133][ C1] ? __pfx___netif_receive_skb_one_core (net/core/dev.c:5597) 
[ 4631.484287][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.484410][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 4631.484548][ C1] ? process_backlog (./include/linux/rcupdate.h:329 ./include/linux/rcupdate.h:781 net/core/dev.c:6046) 
[ 4631.484673][ C1] process_backlog (./include/linux/rcupdate.h:810 net/core/dev.c:6048) 
[ 4631.484797][ C1] __napi_poll.constprop.0 (net/core/dev.c:6701) 
[ 4631.484920][ C1] net_rx_action (net/core/dev.c:6770 net/core/dev.c:6886) 
[ 4631.485045][ C1] ? __pfx_net_rx_action (net/core/dev.c:6850) 
[ 4631.485180][ C1] __do_softirq (kernel/softirq.c:554) 
[ 4631.485305][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 4631.485398][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 4631.485520][    C1]  </IRQ>
[ 4631.485584][    C1]  <TASK>
[ 4631.485646][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 4631.485798][ 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) 
[ 4631.485926][ 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 d3 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 d3 cc 32 00 	verw   0x32ccd3(%rip)        # 0x32ccfb
  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
[ 4631.486368][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 4631.486523][    C1] RAX: 0000000002b04353 RBX: 1ffff92000029fc1 RCX: ffffffff9e734ea5
[ 4631.486707][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9beac0e4
[ 4631.486890][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1709c
[ 4631.487077][    C1] R10: ffff8880360b84e3 R11: ffff8880360ad9b0 R12: 0000000000000000
[ 4631.487259][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 4631.487444][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 4631.487567][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4631.487691][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 4631.487815][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 4631.487946][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 4631.488069][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 4631.488193][ C1] do_idle (kernel/sched/idle.c:332) 
[ 4631.488286][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 4631.488410][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 4631.488532][ 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