list_add corruption. prev->next should be next (ffffffff8a1dca60), but was ffff8881ccab3470. (prev=ffff8881d1d47d70). ------------[ cut here ]------------ kobject: 'kvm' (00000000c91859ec): kobject_uevent_env kernel BUG at lib/list_debug.c:28! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 16772 Comm: syz-executor1 Not tainted 4.20.0-rc6-next-20181210+ #164 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 kobject: 'kvm' (00000000c91859ec): fill_kobj_path: path = '/devices/virtual/misc/kvm' 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: 0018:ffff8881dad06ce0 EFLAGS: 00010286 RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005 RBP: ffff8881dad06cf8 R08: ffff8881b9e52140 R09: ffffed103b5a5020 R10: ffffed103b5a5020 R11: ffff8881dad28107 R12: ffff8881b2ebe2b0 R13: ffff8881b2ebe040 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0 FS: 00007f2d7daaa700(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000625208 CR3: 00000001bb514000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000695b DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __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 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:766 [inline] RIP: 0010:lock_acquire+0x268/0x520 kernel/locking/lockdep.c:3847 Code: 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 44 02 00 00 48 83 3d f7 2d 10 08 00 0f 84 c3 01 00 00 48 8b bd 20 ff ff ff 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 RSP: 0018:ffff88817f716710 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 1ffff1102fee2ce7 RCX: 0000000000000000 RDX: 1ffffffff12e4816 RSI: 0000000000000000 RDI: 0000000000000282 RBP: ffff88817f716800 R08: ffff8881b9e52a08 R09: 0000000000000008 R10: 0000000000000028 R11: ffff8881b9e52140 R12: ffff8881b9e52140 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:223 [inline] rcu_read_lock include/linux/rcupdate.h:607 [inline] lock_page_memcg+0x95/0x350 mm/memcontrol.c:1869 page_remove_file_rmap mm/rmap.c:1219 [inline] page_remove_rmap+0x855/0x1a30 mm/rmap.c:1304 zap_pte_range mm/memory.c:1092 [inline] zap_pmd_range mm/memory.c:1194 [inline] zap_pud_range mm/memory.c:1223 [inline] zap_p4d_range mm/memory.c:1244 [inline] unmap_page_range+0x11c7/0x2930 mm/memory.c:1265 unmap_single_vma+0x19b/0x310 mm/memory.c:1310 unmap_vmas+0x252/0x3d0 mm/memory.c:1345 exit_mmap+0x2be/0x590 mm/mmap.c:3129 __mmput kernel/fork.c:1041 [inline] mmput+0x247/0x610 kernel/fork.c:1062 exit_mm kernel/exit.c:545 [inline] do_exit+0xdeb/0x2620 kernel/exit.c:854 do_group_exit+0x177/0x440 kernel/exit.c:970 get_signal+0x8b0/0x1980 kernel/signal.c:2515 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457679 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2d7daa9cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 000000000072bfa8 RCX: 0000000000457679 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072bfa8 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072bfac R13: 00007ffd1cabd13f R14: 00007f2d7daaa9c0 R15: 000000000072bfac Modules linked in: ---[ end trace 6930957cbc3cad27 ]--- 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: 0018:ffff8881dad06ce0 EFLAGS: 00010286 RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005 RBP: ffff8881dad06cf8 R08: ffff8881b9e52140 R09: ffffed103b5a5020 R10: ffffed103b5a5020 R11: ffff8881dad28107 R12: ffff8881b2ebe2b0 R13: ffff8881b2ebe040 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0 FS: 00007f2d7daaa700(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000625208 CR3: 000000000966e000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000695b DR6: 00000000fffe0ff0 DR7: 0000000000000400