list_add corruption. prev->next should be next (ffffffff89fd0da0), but was ffff8881d7bf42b0. (prev=ffff8881d4465db0). ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:28! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 6257 Comm: syz-executor648 Not tainted 4.20.0-rc4+ #334 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 90 fd d1 fd 0f 0b 48 89 d9 48 c7 c7 a0 d8 60 88 e8 7f fd d1 fd 0f 0b 48 89 f1 48 c7 c7 20 d9 60 88 48 89 de e8 6b fd d1 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:ffff8881dae06cf0 EFLAGS: 00010282 RAX: 0000000000000075 RBX: ffffffff89fd0da0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8165eae5 RDI: 0000000000000005 RBP: ffff8881dae06d08 R08: ffff8881bcdbe000 R09: ffffed103b5c5020 R10: ffffed103b5c5020 R11: ffff8881dae28107 R12: ffff8881ce059030 R13: ffff8881ce058dc0 R14: ffffffff89fd0b60 R15: ffffffff89fd0df0 FS: 0000000000000000(0000) GS:ffff8881dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000042de80 CR3: 00000001bd45f000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 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 cgroup: fork rejected by pids controller in /syz2 cgroup: fork rejected by pids controller in /syz5 __neigh_create+0x30/0x40 net/core/neighbour.c:640 ip6_finish_output2+0xa59/0x27a0 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:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7e5/0xc70 kernel/time/timer.c:1682 cgroup: fork rejected by pids controller in /syz0 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1695 cgroup: fork rejected by pids controller in /syz4 __do_softirq+0x308/0xb7e kernel/softirq.c:292 cgroup: fork rejected by pids controller in /syz3 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:804 RIP: 0010:arch_atomic_add_negative arch/x86/include/asm/atomic.h:154 [inline] RIP: 0010:atomic_add_negative include/asm-generic/atomic-instrumented.h:398 [inline] RIP: 0010:page_remove_file_rmap mm/rmap.c:1235 [inline] RIP: 0010:page_remove_rmap+0x934/0x1a30 mm/rmap.c:1300 Code: 32 6a c7 ff 45 85 ff 0f 85 45 fb ff ff e9 0d f9 ff ff e8 0f 69 c7 ff 48 8d 7b 30 be 04 00 00 00 e8 11 d6 0a 00 f0 83 43 30 ff <41> 0f 98 c4 31 ff 44 89 e6 e8 be 69 c7 ff 45 84 e4 0f 84 3e ff ff RSP: 0018:ffff8881c1786918 EFLAGS: 00000213 ORIG_RAX: ffffffffffffff13 RAX: fffff94000d8c6b7 RBX: ffffea0006c63580 RCX: ffffffff81b821ef RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffea0006c635b0 RBP: ffff8881c1786c88 R08: fffff94000d8c6b7 R09: fffff94000d8c6b6 R10: fffff94000d8c6b6 R11: ffffea0006c635b3 R12: 0000000000000000 R13: ffff8881c1786c60 R14: ffffea0006c63588 R15: 0000000000000000 zap_pte_range mm/memory.c:1091 [inline] zap_pmd_range mm/memory.c:1193 [inline] zap_pud_range mm/memory.c:1222 [inline] zap_p4d_range mm/memory.c:1243 [inline] unmap_page_range+0x11c7/0x2930 mm/memory.c:1264 unmap_single_vma+0x19b/0x310 mm/memory.c:1309 unmap_vmas+0x125/0x200 mm/memory.c:1339 exit_mmap+0x2be/0x590 mm/mmap.c:3145 __mmput kernel/fork.c:1045 [inline] mmput+0x247/0x610 kernel/fork.c:1066 exit_mm kernel/exit.c:545 [inline] do_exit+0xe74/0x26d0 kernel/exit.c:854 do_group_exit+0x177/0x440 kernel/exit.c:970 get_signal+0x8b0/0x1980 kernel/signal.c:2517 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: 0033:0x4480f9 Code: Bad RIP value. RSP: 002b:00007ffccd7c26e8 EFLAGS: 00000202 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 000000000003f97b RCX: 00000000004480f9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dec2c RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffccd7c26f0 R11: 0000000000000202 R12: 00000000000003e8 R13: 00000000006dec2c R14: 00000000006dec20 R15: 000000000000002d Modules linked in: ---[ end trace 32027e846ce348df ]--- RIP: 0010:__list_add_valid.cold.2+0x23/0x2a lib/list_debug.c:26 Code: e8 90 fd d1 fd 0f 0b 48 89 d9 48 c7 c7 a0 d8 60 88 e8 7f fd d1 fd 0f 0b 48 89 f1 48 c7 c7 20 d9 60 88 48 89 de e8 6b fd d1 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:ffff8881dae06cf0 EFLAGS: 00010282 RAX: 0000000000000075 RBX: ffffffff89fd0da0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8165eae5 RDI: 0000000000000005 RBP: ffff8881dae06d08 R08: ffff8881bcdbe000 R09: ffffed103b5c5020 R10: ffffed103b5c5020 R11: ffff8881dae28107 R12: ffff8881ce059030 R13: ffff8881ce058dc0 R14: ffffffff89fd0b60 R15: ffffffff89fd0df0 FS: 0000000000000000(0000) GS:ffff8881dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004480cf CR3: 00000001bd45f000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400