======================================
| [ 2681.153493][    C0] ==================================================================
| [ 2681.153800][ C0] 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) 
| [ 2681.154074][    C0] Read of size 8 at addr 0000000000000008 by task swapper/0/0
| [ 2681.154341][    C0]
[ 2681.154720][    C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 2681.155123][    C0] Call Trace:
[ 2681.155257][    C0]  <IRQ>
[ 2681.155350][ C0] dump_stack_lvl (lib/dump_stack.c:117) 
[ 2681.155544][ C0] kasan_report (mm/kasan/report.c:603) 
[ 2681.155677][ C0] ? 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) 
[ 2681.155902][ C0] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 2681.156072][ C0] 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) 
[ 2681.156260][ C0] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 2681.156391][ C0] skb_release_head_state (net/core/skbuff.c:1162 (discriminator 3)) 
[ 2681.156562][ C0] consume_skb (net/core/skbuff.c:1174 net/core/skbuff.c:1189 net/core/skbuff.c:1405 net/core/skbuff.c:1399) 
[ 2681.156691][ C0] dummy_xmit (drivers/net/dummy.c:66) 
[ 2681.156828][ C0] ? trace_net_dev_start_xmit (./include/trace/events/net.h:14 (discriminator 52)) 
[ 2681.157005][ C0] dev_hard_start_xmit (./include/linux/netdevice.h:4875 ./include/linux/netdevice.h:4889 net/core/dev.c:3563 net/core/dev.c:3579) 
[ 2681.157181][ C0] sch_direct_xmit (net/sched/sch_generic.c:343) 
[ 2681.157356][ C0] ? __pfx_sch_direct_xmit (net/sched/sch_generic.c:318) 
[ 2681.157546][ C0] __qdisc_run (net/sched/sch_generic.c:416) 
[ 2681.157718][ C0] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 2681.157890][ C0] ? __pfx___qdisc_run (net/sched/sch_generic.c:412) 
[ 2681.158066][ C0] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:115 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 2681.158239][ C0] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 2681.158420][ C0] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 2681.158596][ C0] ? net_tx_action (./include/linux/spinlock.h:352 net/core/dev.c:5250) 
[ 2681.158775][ C0] net_tx_action (./include/net/sch_generic.h:217 ./include/net/pkt_sched.h:128 ./include/net/pkt_sched.h:124 net/core/dev.c:5266) 
[ 2681.158945][ C0] __do_softirq (kernel/softirq.c:554) 
[ 2681.159120][ C0] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 2681.159253][ C0] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 2681.159429][    C0]  </IRQ>
[ 2681.159519][    C0]  <TASK>
[ 2681.159607][ C0] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 2681.159828][ C0] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/kernel/process.c:743) 
[ 2681.160026][ C0] 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 e3 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 e3 cc 32 00 	verw   0x32cce3(%rip)        # 0x32cd0b
  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
[ 2681.160631][    C0] RSP: 0018:ffffffffa3207e00 EFLAGS: 00000246
[ 2681.160856][    C0] RAX: 000000000385807d RBX: 1ffffffff4640fc2 RCX: ffffffffa2334e95
[ 2681.161118][    C0] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9faac0e4
[ 2681.161379][    C0] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c0709c
[ 2681.161642][    C0] R10: ffff8880360384e3 R11: ffff88803602d9b0 R12: 0000000000000000
[ 2681.161903][    C0] R13: ffffffffa3231000 R14: dffffc0000000000 R15: 0000000000014770
[ 2681.162162][ C0] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 2681.162339][ C0] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.162513][ C0] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 2681.162686][ C0] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.162860][ C0] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 2681.163034][ C0] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 2681.163214][ C0] do_idle (kernel/sched/idle.c:332) 
[ 2681.163351][ C0] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 2681.163526][ C0] rest_init (./include/linux/rcupdate.h:782 init/main.c:703) 
[ 2681.163654][ C0] start_kernel (init/main.c:1024 (discriminator 1)) 
[ 2681.163838][ C0] x86_64_start_reservations (arch/x86/kernel/head64.c:495) 
[ 2681.164012][ C0] x86_64_start_kernel (arch/x86/kernel/head64.c:437 (discriminator 17)) 
[ 2681.164194][ C0] common_startup_64 (arch/x86/kernel/head_64.S:421) 
| [ 2681.164502][    C0] ==================================================================
| [ 2681.164762][    C0] Disabling lock debugging due to kernel taint
| [ 2681.165003][    C0] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [ 2681.165406][    C0] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 2681.165962][    C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 2681.166357][ C0] 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) 
[ 2681.166568][ C0] 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
[ 2681.167196][    C0] RSP: 0018:ffffc90000007c30 EFLAGS: 00010202
[ 2681.167415][    C0] RAX: dffffc0000000000 RBX: ffff888006480040 RCX: ffffffff9f99564a
[ 2681.167681][    C0] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffa4efda00
[ 2681.167937][    C0] RBP: ffff8880064800a0 R08: 0000000000000001 R09: fffffbfff49dfb40
[ 2681.168207][    C0] R10: ffffffffa4efda07 R11: 205d304320202020 R12: 0000000000000000
[ 2681.168467][    C0] R13: ffff8880064801c0 R14: 0000000000000008 R15: 0000000000000000
[ 2681.168722][    C0] FS:  0000000000000000(0000) GS:ffff888036000000(0000) knlGS:0000000000000000
[ 2681.169130][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2681.169447][    C0] CR2: 00007f79ba5d5000 CR3: 0000000028738003 CR4: 0000000000770ef0
[ 2681.169705][    C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2681.169978][    C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2681.170235][    C0] PKRU: 55555554
[ 2681.170371][    C0] Call Trace:
[ 2681.170509][    C0]  <IRQ>
[ 2681.170600][ C0] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 2681.170735][ C0] ? exc_general_protection (arch/x86/kernel/traps.c:702 arch/x86/kernel/traps.c:644) 
[ 2681.170908][ C0] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 2681.171078][ C0] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:555) 
[ 2681.171208][ C0] ? 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) 
[ 2681.171421][ C0] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 2681.171636][ C0] skb_release_head_state (net/core/skbuff.c:1162 (discriminator 3)) 
[ 2681.171808][ C0] consume_skb (net/core/skbuff.c:1174 net/core/skbuff.c:1189 net/core/skbuff.c:1405 net/core/skbuff.c:1399) 
[ 2681.171933][ C0] dummy_xmit (drivers/net/dummy.c:66) 
[ 2681.172064][ C0] ? trace_net_dev_start_xmit (./include/trace/events/net.h:14 (discriminator 52)) 
[ 2681.172234][ C0] dev_hard_start_xmit (./include/linux/netdevice.h:4875 ./include/linux/netdevice.h:4889 net/core/dev.c:3563 net/core/dev.c:3579) 
[ 2681.172498][ C0] sch_direct_xmit (net/sched/sch_generic.c:343) 
[ 2681.172672][ C0] ? __pfx_sch_direct_xmit (net/sched/sch_generic.c:318) 
[ 2681.172844][ C0] __qdisc_run (net/sched/sch_generic.c:416) 
[ 2681.173015][ C0] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 2681.173277][ C0] ? __pfx___qdisc_run (net/sched/sch_generic.c:412) 
[ 2681.173446][ C0] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:115 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 2681.173616][ C0] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 2681.173783][ C0] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 2681.173958][ C0] ? net_tx_action (./include/linux/spinlock.h:352 net/core/dev.c:5250) 
[ 2681.174126][ C0] net_tx_action (./include/net/sch_generic.h:217 ./include/net/pkt_sched.h:128 ./include/net/pkt_sched.h:124 net/core/dev.c:5266) 
[ 2681.174298][ C0] __do_softirq (kernel/softirq.c:554) 
[ 2681.174466][ C0] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 2681.174593][ C0] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 2681.174771][    C0]  </IRQ>
[ 2681.174858][    C0]  <TASK>
[ 2681.174944][ C0] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 2681.175162][ C0] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/kernel/process.c:743) 
[ 2681.175346][ C0] 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 e3 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 e3 cc 32 00 	verw   0x32cce3(%rip)        # 0x32cd0b
  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
[ 2681.176061][    C0] RSP: 0018:ffffffffa3207e00 EFLAGS: 00000246
[ 2681.176278][    C0] RAX: 000000000385807d RBX: 1ffffffff4640fc2 RCX: ffffffffa2334e95
[ 2681.176639][    C0] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9faac0e4
[ 2681.176872][    C0] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c0709c
[ 2681.177202][    C0] R10: ffff8880360384e3 R11: ffff88803602d9b0 R12: 0000000000000000
[ 2681.177440][    C0] R13: ffffffffa3231000 R14: dffffc0000000000 R15: 0000000000014770
[ 2681.177777][ C0] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 2681.177939][ C0] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.178103][ C0] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 2681.178258][ C0] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.178511][ C0] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 2681.178669][ C0] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 2681.178830][ C0] do_idle (kernel/sched/idle.c:332) 
[ 2681.178949][ C0] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 2681.179106][ C0] rest_init (./include/linux/rcupdate.h:782 init/main.c:703) 
[ 2681.179319][ C0] start_kernel (init/main.c:1024 (discriminator 1)) 
[ 2681.179474][ C0] x86_64_start_reservations (arch/x86/kernel/head64.c:495) 
[ 2681.179628][ C0] x86_64_start_kernel (arch/x86/kernel/head64.c:437 (discriminator 17)) 


Finger prints:
dump_stack_lvl:kasan_report:kasan_check_range:sock_def_write_space_wfree
sock_def_write_space_wfree:sock_wfree:skb_release_head_state:consume_skb