list_add corruption. next->prev should be prev (ffff8880ae72d8d8), but was 0000000000000000. (next=ffff8880a94c44f0). ------------[ cut here ]------------ kasan: CONFIG_KASAN_INLINE enabled kernel BUG at lib/list_debug.c:23! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 3 Comm: Not tainted 4.20.0-rc7-next-20181224 #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__list_add_valid.cold+0xf/0x3c lib/list_debug.c:23 Code: 34 fe eb d5 4c 89 e7 e8 1a 01 34 fe eb a3 4c 89 f7 e8 10 01 34 fe e9 56 ff ff ff 4c 89 e1 48 c7 c7 80 9e 81 88 e8 00 5e d6 fd <0f> 0b 48 89 f2 4c 89 e1 4c 89 ee 48 c7 c7 c0 9f 81 88 e8 e9 5d d6 RSP: 0018:ffff8880ae707648 EFLAGS: 00010086 RAX: 0000000000000075 RBX: ffff888084e287c0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8167d966 RDI: ffffed1015ce0ebb RBP: ffff8880ae707660 R08: 0000000000000075 R09: ffffed1015ce5021 R10: ffffed1015ce5020 R11: ffff8880ae728107 R12: ffff8880a94c44f0 R13: ffff88809704a3b0 R14: ffff8880ae7076e8 R15: ffff88809704a3b0 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbf349e4db8 CR3: 000000009701f000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:60 [inline] list_add include/linux/list.h:79 [inline] account_entity_enqueue+0x3a0/0x660 kernel/sched/fair.c:2679 enqueue_entity+0x276/0x20b0 kernel/sched/fair.c:3903 enqueue_task_fair+0x237/0x10c0 kernel/sched/fair.c:5134 enqueue_task kernel/sched/core.c:730 [inline] activate_task+0x11d/0x470 kernel/sched/core.c:751 ttwu_activate kernel/sched/core.c:1643 [inline] ttwu_do_activate+0xd4/0x1f0 kernel/sched/core.c:1702 ttwu_queue kernel/sched/core.c:1847 [inline] try_to_wake_up+0x997/0x1480 kernel/sched/core.c:2057 wake_up_process+0x10/0x20 kernel/sched/core.c:2129 hrtimer_wakeup+0x48/0x60 kernel/time/hrtimer.c:1637 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x3a7/0x1050 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline] smp_apic_timer_interrupt+0x18d/0x760 arch/x86/kernel/apic/apic.c:1060 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 Modules linked in: ---[ end trace e4c4e37cc4b3fde2 ]--- kernel tried to execute NX-protected page - exploit attempt? (uid: 0) BUG: unable to handle kernel paging request at ffff8880915977c0 RIP: 0010:__list_add_valid.cold+0xf/0x3c lib/list_debug.c:23 #PF error: [PROT] [INSTR] Code: 34 fe eb d5 4c 89 e7 e8 1a 01 34 fe eb a3 4c 89 f7 e8 10 01 34 fe e9 56 ff ff ff 4c 89 e1 48 c7 c7 80 9e 81 88 e8 00 5e d6 fd <0f> 0b 48 89 f2 4c 89 e1 4c 89 ee 48 c7 c7 c0 9f 81 88 e8 e9 5d d6 PGD c201067 P4D c201067 PUD 21ffff067 PMD 80000000914001e3 RSP: 0018:ffff8880ae707648 EFLAGS: 00010086 Oops: 0011 [#2] PREEMPT SMP KASAN RAX: 0000000000000075 RBX: ffff888084e287c0 RCX: 0000000000000000 CPU: 0 PID: 8862 Comm: syz-executor2 Tainted: G D 4.20.0-rc7-next-20181224 #1 RDX: 0000000000000000 RSI: ffffffff8167d966 RDI: ffffed1015ce0ebb Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RBP: ffff8880ae707660 R08: 0000000000000075 R09: ffffed1015ce5021 RIP: 0010:0xffff8880915977c0 R10: ffffed1015ce5020 R11: ffff8880ae728107 R12: ffff8880a94c44f0 Code: ff ff 00 00 00 00 00 00 00 00 7d fd c3 1e 9a c4 75 15 01 00 65 74 68 30 00 00 00 00 00 00 34 00 00 00 08 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 40 24 fe a4 80 88 R13: ffff88809704a3b0 R14: ffff8880ae7076e8 R15: ffff88809704a3b0 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 RSP: 0018:ffff8880ae6079b0 EFLAGS: 00010206 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 RAX: ffff8880915977c0 RBX: ffff8880a9487928 RCX: ffffffff816ea433 CR2: 00007fbf349e4db8 CR3: 000000009701f000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 RDX: 0000000000000100 RSI: ffffffff816e9f25 RDI: ffff8880a9487928 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400