list_add corruption. prev->next should be next (ffffffff8a1dca60), but was ffff8881d209f4b0. (prev=ffff8881b94e6270).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:28!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 28172 Comm: syz-executor029 Not tainted 4.20.0-rc6-next-20181210+ #164
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_add_valid.cold.2+0x23/0x2a lib/list_debug.c:26
Code: e8 00 1f d2 fd 0f 0b 48 89 d9 48 c7 c7 20 e6 80 88 e8 ef 1e d2 fd 0f 0b 48 89 f1 48 c7 c7 a0 e6 80 88 48 89 de e8 db 1e d2 fd <0f> 0b 90 90 90 90 90 55 48 89 e5 41 57 41 56 49 be 00 00 00 00 00
RSP: 0000:ffff8881dad06ce0 EFLAGS: 00010286
RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005
RBP: ffff8881dad06cf8 R08: ffff8881d1aa8540 R09: ffffed103b5a5020
R10: ffffed103b5a5020 R11: ffff8881dad28107 R12: ffff8881d260f8f0
R13: ffff8881d260f680 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0
FS:  00000000006fa880(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006fab50 CR3: 00000001d1986000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __list_add include/linux/list.h:60 [inline]
 list_add_tail include/linux/list.h:93 [inline]
 neigh_alloc net/core/neighbour.c:395 [inline]
 ___neigh_create+0x14b7/0x2600 net/core/neighbour.c:553
 __neigh_create+0x30/0x40 net/core/neighbour.c:640
 ip6_finish_output2+0xa64/0x2940 net/ipv6/ip6_output.c:117
 ip6_finish_output+0x58c/0xc60 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ndisc_send_skb+0x1005/0x1560 net/ipv6/ndisc.c:491
 ndisc_send_rs+0x134/0x6e0 net/ipv6/ndisc.c:685
 addrconf_rs_timer+0x314/0x690 net/ipv6/addrconf.c:3840
 call_timer_fn+0x272/0x920 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers+0x7e5/0xc70 kernel/time/timer.c:1681
 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1694
 __do_softirq+0x308/0xb7e kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x17f/0x1c0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1061
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:776 [inline]
RIP: 0010:do_user_addr_fault arch/x86/mm/fault.c:1378 [inline]
RIP: 0010:__do_page_fault+0x793/0xd70 arch/x86/mm/fault.c:1541
Code: 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 53 05 00 00 48 83 3d af b9 39 08 00 0f 84 db 04 00 00 e8 f4 70 47 00 fb 66 0f 1f 44 00 00 <c7> 45 c4 14 00 00 00 e9 06 fb ff ff e8 dc 70 47 00 48 89 de 4c 89
RSP: 0000:ffff8881d1c5fcb0 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff8881d1aa8540 RBX: 00000000006fab50 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8138871c RDI: ffffffff897240c0
RBP: ffff8881d1c5fd18 R08: ffff8881d1aa8540 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881d1c5fe88
R13: 00000000006fa000 R14: ffff8881d1aa8540 R15: 0000000000000000
 do_page_fault+0xf2/0x7e0 arch/x86/mm/fault.c:1572
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1143
RIP: 0010:__put_user_4+0x1c/0x30 arch/x86/lib/putuser.S:68
Code: 1f 00 c3 90 66 2e 0f 1f 84 00 00 00 00 00 65 48 8b 1c 25 40 ee 01 00 48 8b 9b 18 14 00 00 48 83 eb 03 48 39 d9 73 3c 0f 1f 00 <89> 01 31 c0 0f 1f 00 c3 66 90 66 2e 0f 1f 84 00 00 00 00 00 65 48
RSP: 0000:ffff8881d1c5ff30 EFLAGS: 00010297
RAX: 00000000000023f4 RBX: 00007fffffffeffd RCX: 00000000006fab50
RDX: dffffc0000000000 RSI: 1ffff1103a3551b8 RDI: ffff8881d1aa8ae8
RBP: ffff8881d1c5ff48 R08: 1ffff1103a38bfb4 R09: ffffed103b5a5b5f
R10: 0000000000000001 R11: ffff8881dad2dafb R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 ret_from_fork+0x8/0x50 arch/x86/entry/entry_64.S:336
RIP: 0033:0x4441ca
Code: Bad RIP value.
RSP: 002b:00007ffc20ee8660 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000004441ca
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffc20ee8680 R08: 0000000000000001 R09: 00000000006fa880
R10: 00000000006fab50 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000004025f0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 08b8931d4d62f1ef ]---
RIP: 0010:__list_add_valid.cold.2+0x23/0x2a lib/list_debug.c:26
Code: e8 00 1f d2 fd 0f 0b 48 89 d9 48 c7 c7 20 e6 80 88 e8 ef 1e d2 fd 0f 0b 48 89 f1 48 c7 c7 a0 e6 80 88 48 89 de e8 db 1e d2 fd <0f> 0b 90 90 90 90 90 55 48 89 e5 41 57 41 56 49 be 00 00 00 00 00
RSP: 0000:ffff8881dad06ce0 EFLAGS: 00010286
RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005
RBP: ffff8881dad06cf8 R08: ffff8881d1aa8540 R09: ffffed103b5a5020
R10: ffffed103b5a5020 R11: ffff8881dad28107 R12: ffff8881d260f8f0
R13: ffff8881d260f680 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0
FS:  00000000006fa880(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004441a0 CR3: 00000001d1986000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400