Debian GNU/Linux 7 syzkaller ttyS0 executing program syzkaller login: [ 15.508196] kasan: CONFIG_KASAN_INLINE enabled [ 15.508653] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 15.509337] general protection fault: 0000 [#1] SMP KASAN [ 15.509835] Dumping ftrace buffer: [ 15.510194] (ftrace buffer empty) [ 15.510521] Modules linked in: [ 15.510807] CPU: 2 PID: 3008 Comm: syzkaller007950 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 15.511496] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 15.512099] task: ffff88003e3d2140 task.stack: ffff88003d578000 [ 15.512549] RIP: 0010:hrtimer_active+0x211/0x410 [ 15.512913] RSP: 0018:ffff88003d57f3f0 EFLAGS: 00010246 [ 15.513377] RAX: 0000000000000000 RBX: 1ffff10007aafeab RCX: ffffffff815ef89f [ 15.514911] RDX: 0000000000000000 RSI: ffffffff85b376a0 RDI: ffff88006ce9f320 [ 15.515449] RBP: ffff88003d57f530 R08: ffffffff83f9e367 R09: 0000000000000004 [ 15.515982] R10: ffff88003d57f898 R11: 0000000000000000 R12: 0000000000000000 [ 15.516516] R13: 0000000000000000 R14: ffffed0007aafe89 R15: dffffc0000000000 [ 15.518084] FS: 0000000000000000(0000) GS:ffff88006de00000(0000) knlGS:0000000000000000 [ 15.518704] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.519268] CR2: 0000000020511fd8 CR3: 0000000005a22000 CR4: 00000000000006e0 [ 15.520259] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 15.520910] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 15.521564] Call Trace: [ 15.521796] ? hrtimer_forward+0x2d0/0x2d0 [ 15.522199] ? __might_sleep+0x95/0x190 [ 15.522564] ? rtnl_lock+0x17/0x20 [ 15.522894] ? __mutex_lock+0x16f/0x19d0 [ 15.523265] ? rtnl_lock+0x17/0x20 [ 15.523591] ? fsnotify+0xb6f/0x1af0 [ 15.523932] ? rtnl_lock+0x17/0x20 [ 15.524577] hrtimer_try_to_cancel+0x91/0x5c0 [ 15.524992] ? __hrtimer_get_remaining+0x1c0/0x1c0 [ 15.525456] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 15.525997] ? __free_insn_slot+0x5c0/0x5c0 [ 15.526396] ? rcu_note_context_switch+0x710/0x710 [ 15.526851] ? __lock_is_held+0xb6/0x140 [ 15.527230] hrtimer_cancel+0x22/0x40 [ 15.527583] napi_disable+0x87/0xa0 [ 15.527920] __tun_detach+0xe26/0x1570 [ 15.528282] ? __kernel_text_address+0xd/0x40 [ 15.528844] ? unwind_get_return_address+0x61/0xa0 [ 15.529300] ? tun_attach+0x1080/0x1080 [ 15.529673] ? check_noncircular+0x20/0x20 [ 15.530136] ? locks_remove_file+0x3fa/0x5a0 [ 15.530546] ? fcntl_setlk+0x10c0/0x10c0 [ 15.530925] ? free_fs_struct+0x4f/0x60 [ 15.531292] ? __fsnotify_parent+0xb4/0x3a0 [ 15.531688] ? fsnotify+0x1af0/0x1af0 [ 15.532043] ? rcu_note_context_switch+0x710/0x710 [ 15.532501] ? __tun_detach+0x1570/0x1570 [ 15.532883] ? __tun_detach+0x1570/0x1570 [ 15.533266] tun_chr_close+0x44/0x60 [ 15.533770] __fput+0x327/0x7e0 [ 15.534082] ? fput+0x140/0x140 [ 15.534388] ? _raw_spin_unlock_irq+0x27/0x70 [ 15.534810] ____fput+0x15/0x20 [ 15.535142] task_work_run+0x199/0x270 [ 15.535503] ? task_work_cancel+0x210/0x210 [ 15.535898] ? _raw_spin_unlock+0x22/0x30 [ 15.536272] ? switch_task_namespaces+0x87/0xc0 [ 15.536700] do_exit+0x9b5/0x1ad0 [ 15.537023] ? mm_update_next_owner+0x930/0x930 [ 15.537448] ? rtnl_unlock+0xe/0x10 [ 15.537782] ? __tun_chr_ioctl+0x27a/0x3e50 [ 15.538221] ? unwind_get_return_address+0x14/0xa0 [ 15.538666] ? tun_chr_read_iter+0x1e0/0x1e0 [ 15.539070] ? putname+0xee/0x130 [ 15.539388] ? save_stack+0xa3/0xd0 [ 15.539719] ? save_stack+0x43/0xd0 [ 15.540050] ? kasan_slab_free+0x71/0xc0 [ 15.540424] ? kmem_cache_free+0x77/0x280 [ 15.540808] ? putname+0xee/0x130 [ 15.541126] ? do_sys_open+0x31b/0x6d0 [ 15.541487] ? __lock_is_held+0xb6/0x140 [ 15.541873] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 15.542459] ? tun_chr_compat_ioctl+0x30/0x30 [ 15.542872] ? tun_chr_ioctl+0x2a/0x40 [ 15.543231] ? tun_chr_ioctl+0x2a/0x40 [ 15.543590] ? do_vfs_ioctl+0x486/0x1520 [ 15.543963] ? _cond_resched+0x14/0x30 [ 15.544324] ? ioctl_preallocate+0x2b0/0x2b0 [ 15.544730] ? selinux_capable+0x40/0x40 [ 15.545105] ? putname+0xf3/0x130 [ 15.545428] do_group_exit+0x149/0x400 [ 15.545786] ? SyS_exit+0x30/0x30 [ 15.546346] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 15.546807] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 15.547246] SyS_exit_group+0x1d/0x20 [ 15.547597] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 15.548030] RIP: 0033:0x437c39 [ 15.548322] RSP: 002b:00007fffd8d05838 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 15.549022] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000437c39 [ 15.549678] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 15.550385] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 15.551089] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 74656e2f7665642f [ 15.551760] R13: 0000000000401cf0 R14: 0000000000401d80 R15: 0000000000000000 [ 15.552427] Code: c6 00 00 48 8b 85 d8 fe ff ff 48 c1 e8 03 42 80 3c 38 00 0f 85 f2 01 00 00 48 8b 85 e8 fe ff ff 4c 8b 60 30 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 c8 01 00 00 48 8b 85 f0 fe ff ff 49 8b 1c [ 15.554311] RIP: hrtimer_active+0x211/0x410 RSP: ffff88003d57f3f0 [ 15.554911] ---[ end trace f0d7e3202678b826 ]--- [ 15.555381] Kernel panic - not syncing: Fatal exception [ 15.555924] Dumping ftrace buffer: [ 15.556333] (ftrace buffer empty) [ 15.556695] Kernel Offset: disabled [ 15.557044] Rebooting in 86400 seconds..