list_add corruption. next->prev should be prev (ffff8881c3d9a730), but was ffff8881b2a6c6f0. (next=ffffffff8a1dca60). ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:25! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 7698 Comm: syz-executor4 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+0xf/0x2a lib/list_debug.c:23 Code: e5 80 88 e8 11 1f d2 fd 0f 0b 48 89 de 48 c7 c7 60 e5 80 88 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 kobject: 'loop1' (00000000ae275935): kobject_uevent_env RSP: 0018:ffff8881dac06ce0 EFLAGS: 00010286 RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005 RBP: ffff8881dac06cf8 R08: ffff88818bd30180 R09: ffffed103b585020 R10: ffffed103b585020 R11: ffff8881dac28107 R12: ffff8881d93626f0 R13: ffff8881d9362480 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0 kobject: 'loop1' (00000000ae275935): fill_kobj_path: path = '/devices/virtual/block/loop1' FS: 0000000001017940(0000) GS:ffff8881dac00000(0000) knlGS:0000000000000000 kobject: 'loop0' (00000000ff4241a0): kobject_uevent_env CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000930000 CR3: 000000018d2b1000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 kobject: 'loop0' (00000000ff4241a0): fill_kobj_path: path = '/devices/virtual/block/loop0' 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 kobject: 'loop5' (00000000ef3f4b1e): kobject_uevent_env kobject: 'loop5' (00000000ef3f4b1e): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop3' (000000000605d8a5): kobject_uevent_env kobject: 'loop3' (000000000605d8a5): fill_kobj_path: path = '/devices/virtual/block/loop3' __neigh_create+0x30/0x40 net/core/neighbour.c:640 ip6_finish_output2+0xa64/0x2940 net/ipv6/ip6_output.c:117 binder: 7705 BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero. binder: 7705:7715 ioctl c018620c 200000c0 returned -22 kobject: 'loop0' (00000000ff4241a0): kobject_uevent_env kobject: 'loop0' (00000000ff4241a0): fill_kobj_path: path = '/devices/virtual/block/loop0' binder: 7721 BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero. binder: 7721:7723 ioctl c018620c 200000c0 returned -22 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 kobject: 'loop3' (000000000605d8a5): kobject_uevent_env 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 kobject: 'loop3' (000000000605d8a5): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop0' (00000000ff4241a0): kobject_uevent_env 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 kobject: 'loop0' (00000000ff4241a0): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (00000000ae275935): kobject_uevent_env kobject: 'loop1' (00000000ae275935): fill_kobj_path: path = '/devices/virtual/block/loop1' expire_timers kernel/time/timer.c:1362 [inline] __run_timers+0x7e5/0xc70 kernel/time/timer.c:1681 kobject: 'loop5' (00000000ef3f4b1e): kobject_uevent_env kobject: 'loop5' (00000000ef3f4b1e): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop3' (000000000605d8a5): kobject_uevent_env kobject: 'loop3' (000000000605d8a5): fill_kobj_path: path = '/devices/virtual/block/loop3' 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:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:146 Code: 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 <55> 48 89 e5 48 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 a8 f5 RSP: 0018:ffff88818bd27050 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: 1ffff110317a4e3b RBX: ffff88818bd27600 RCX: ffff8881bfe754e0 RDX: 0000000000000000 RSI: ffffffff81b378b6 RDI: 0000000000000001 RBP: ffff88818bd27480 R08: ffff88818bd30180 R09: fffff94000c70af6 R10: fffff94000c70af6 R11: ffffea00063857b3 R12: 0000000000000001 R13: 00007faa3e29d000 R14: dffffc0000000000 R15: ffffea00063857c0 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 __do_sys_exit_group kernel/exit.c:981 [inline] __se_sys_exit_group kernel/exit.c:979 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:979 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 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:00007ffeab32f6a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 0000000000457679 RDX: 0000000000411110 RSI: 00000000000001cd RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000004 R15: 0000000000000004 Modules linked in: ---[ end trace 53dc1e2765712fd4 ]--- RIP: 0010:__list_add_valid.cold.2+0xf/0x2a lib/list_debug.c:23 Code: e5 80 88 e8 11 1f d2 fd 0f 0b 48 89 de 48 c7 c7 60 e5 80 88 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 RSP: 0018:ffff8881dac06ce0 EFLAGS: 00010286 RAX: 0000000000000075 RBX: ffffffff8a1dca60 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005 RBP: ffff8881dac06cf8 R08: ffff88818bd30180 R09: ffffed103b585020 R10: ffffed103b585020 R11: ffff8881dac28107 R12: ffff8881d93626f0 R13: ffff8881d9362480 R14: ffffffff8a1dc820 R15: ffffffff8a1dcab0 FS: 0000000001017940(0000) GS:ffff8881dac00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000930000 CR3: 000000018d2b1000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400