======================================
| [ 2681.738471][    C1] ==================================================================
| [ 2681.738725][ 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) 
| [ 2681.738956][    C1] Read of size 8 at addr 0000000000000008 by task swapper/1/0
| [ 2681.739164][    C1]
[ 2681.739470][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 2681.739773][    C1] Call Trace:
[ 2681.739889][    C1]  <IRQ>
[ 2681.739968][ C1] dump_stack_lvl (lib/dump_stack.c:117) 
[ 2681.740117][ C1] kasan_report (mm/kasan/report.c:603) 
[ 2681.740224][ 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) 
[ 2681.740403][ C1] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 2681.740541][ 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) 
[ 2681.740679][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 2681.740781][ C1] skb_release_head_state (net/core/skbuff.c:1162 (discriminator 3)) 
[ 2681.740927][ C1] consume_skb (net/core/skbuff.c:1174 net/core/skbuff.c:1189 net/core/skbuff.c:1405 net/core/skbuff.c:1399) 
[ 2681.741030][ C1] dummy_xmit (drivers/net/dummy.c:66) 
[ 2681.741133][ C1] ? trace_net_dev_start_xmit (./include/trace/events/net.h:14 (discriminator 52)) 
[ 2681.741281][ C1] dev_hard_start_xmit (./include/linux/netdevice.h:4875 ./include/linux/netdevice.h:4889 net/core/dev.c:3563 net/core/dev.c:3579) 
[ 2681.741431][ C1] sch_direct_xmit (net/sched/sch_generic.c:343) 
[ 2681.741573][ C1] ? __pfx_sch_direct_xmit (net/sched/sch_generic.c:318) 
[ 2681.741710][ C1] __qdisc_run (net/sched/sch_generic.c:416) 
[ 2681.741844][ C1] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 2681.741982][ C1] ? __pfx___qdisc_run (net/sched/sch_generic.c:412) 
[ 2681.742114][ C1] ? 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) 
[ 2681.742249][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 2681.742382][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 2681.742519][ C1] ? net_tx_action (./include/linux/spinlock.h:352 net/core/dev.c:5250) 
[ 2681.742661][ C1] 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) 
[ 2681.742797][ C1] __do_softirq (kernel/softirq.c:554) 
[ 2681.742933][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 2681.743038][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 2681.743177][    C1]  </IRQ>
[ 2681.743247][    C1]  <TASK>
[ 2681.743315][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 2681.743480][ 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) 
[ 2681.743622][ 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 a3 dc 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 a3 dc 32 00 	verw   0x32dca3(%rip)        # 0x32dccb
  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
[ 2681.744110][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 2681.744285][    C1] RAX: 0000000003e972dd RBX: 1ffff92000029fc1 RCX: ffffffffa0d33ed5
[ 2681.744492][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9e4ac0e4
[ 2681.744701][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005ed709c
[ 2681.744921][    C1] R10: ffff88802f6b84e3 R11: ffff88802f6ad9b0 R12: 0000000000000000
[ 2681.745127][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 2681.745347][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 2681.745498][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.745638][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 2681.745776][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.745909][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 2681.746052][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 2681.746193][ C1] do_idle (kernel/sched/idle.c:332) 
[ 2681.746292][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 2681.746435][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 2681.746573][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:231) 
[ 2681.746715][ C1] common_startup_64 (arch/x86/kernel/head_64.S:421) 
| [ 2681.746968][    C1] ==================================================================
| [ 2681.747175][    C1] Disabling lock debugging due to kernel taint
| [ 2681.747375][    C1] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [ 2681.747684][    C1] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 2681.748142][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 2681.748448][ 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) 
[ 2681.748625][ 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
[ 2681.749110][    C1] RSP: 0018:ffffc900001d8c30 EFLAGS: 00010202
[ 2681.749283][    C1] RAX: dffffc0000000000 RBX: ffff888005711140 RCX: ffffffff9e39564a
[ 2681.749490][    C1] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffa38fda00
[ 2681.749699][    C1] RBP: ffff8880057111a0 R08: 0000000000000001 R09: fffffbfff471fb40
[ 2681.749908][    C1] R10: ffffffffa38fda07 R11: 205d314320202020 R12: 0000000000000000
[ 2681.750116][    C1] R13: ffff8880057112c0 R14: 0000000000000008 R15: 0000000000000000
[ 2681.750326][    C1] FS:  0000000000000000(0000) GS:ffff88802f680000(0000) knlGS:0000000000000000
[ 2681.750571][    C1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2681.750749][    C1] CR2: 000055c576848dec CR3: 0000000005850001 CR4: 0000000000770ef0
[ 2681.750965][    C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2681.751163][    C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2681.751366][    C1] PKRU: 55555554
[ 2681.751472][    C1] Call Trace:
[ 2681.751577][    C1]  <IRQ>
[ 2681.751649][ C1] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 2681.751761][ C1] ? exc_general_protection (arch/x86/kernel/traps.c:702 arch/x86/kernel/traps.c:644) 
[ 2681.751903][ C1] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 2681.752045][ C1] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:555) 
[ 2681.752148][ 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) 
[ 2681.752317][ C1] sock_wfree (./include/linux/rcupdate.h:810 net/core/sock.c:2471) 
[ 2681.752423][ C1] skb_release_head_state (net/core/skbuff.c:1162 (discriminator 3)) 
[ 2681.752562][ C1] consume_skb (net/core/skbuff.c:1174 net/core/skbuff.c:1189 net/core/skbuff.c:1405 net/core/skbuff.c:1399) 
[ 2681.752670][ C1] dummy_xmit (drivers/net/dummy.c:66) 
[ 2681.752772][ C1] ? trace_net_dev_start_xmit (./include/trace/events/net.h:14 (discriminator 52)) 
[ 2681.752912][ C1] dev_hard_start_xmit (./include/linux/netdevice.h:4875 ./include/linux/netdevice.h:4889 net/core/dev.c:3563 net/core/dev.c:3579) 
[ 2681.753048][ C1] sch_direct_xmit (net/sched/sch_generic.c:343) 
[ 2681.753193][ C1] ? __pfx_sch_direct_xmit (net/sched/sch_generic.c:318) 
[ 2681.753333][ C1] __qdisc_run (net/sched/sch_generic.c:416) 
[ 2681.753471][ C1] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 2681.753606][ C1] ? __pfx___qdisc_run (net/sched/sch_generic.c:412) 
[ 2681.753744][ C1] ? 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) 
[ 2681.753881][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 2681.754018][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 2681.754159][ C1] ? net_tx_action (./include/linux/spinlock.h:352 net/core/dev.c:5250) 
[ 2681.754297][ C1] 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) 
[ 2681.754434][ C1] __do_softirq (kernel/softirq.c:554) 
[ 2681.754576][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 2681.754686][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[ 2681.754820][    C1]  </IRQ>
[ 2681.754892][    C1]  <TASK>
[ 2681.754966][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 2681.755131][ 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) 
[ 2681.755274][ 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 a3 dc 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 a3 dc 32 00 	verw   0x32dca3(%rip)        # 0x32dccb
  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
[ 2681.755750][    C1] RSP: 0018:ffffc9000014fdf8 EFLAGS: 00000246
[ 2681.755925][    C1] RAX: 0000000003e972dd RBX: 1ffff92000029fc1 RCX: ffffffffa0d33ed5
[ 2681.756132][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9e4ac0e4
[ 2681.756332][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005ed709c
[ 2681.756532][    C1] R10: ffff88802f6b84e3 R11: ffff88802f6ad9b0 R12: 0000000000000000
[ 2681.756746][    C1] R13: ffff888001b8a300 R14: dffffc0000000000 R15: 0000000000000000
[ 2681.756953][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:147) 
[ 2681.757090][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.757228][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 2681.757362][ C1] cpuidle_idle_call (kernel/sched/idle.c:192) 
[ 2681.757497][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 2681.757635][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 2681.757768][ C1] do_idle (kernel/sched/idle.c:332) 
[ 2681.757870][ C1] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) 
[ 2681.758004][ C1] start_secondary (arch/x86/kernel/smpboot.c:201 arch/x86/kernel/smpboot.c:281) 
[ 2681.758134][ 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:skb_release_head_state:consume_skb