INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added 'ci-upstream-next-kasan-gce-6,10.128.0.33' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 33.131076] ------------[ cut here ]------------ [ 33.131809] WARNING: CPU: 1 PID: 3096 at kernel/kthread.c:87 free_kthread_struct+0xa2/0xe0 [ 33.133043] Kernel panic - not syncing: panic_on_warn set ... [ 33.133043] [ 33.134016] CPU: 1 PID: 3096 Comm: syzkaller730052 Not tainted 4.14.0-rc7-next-20171103+ #38 [ 33.135180] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.136491] Call Trace: [ 33.136843] [ 33.137149] dump_stack+0x194/0x257 [ 33.137661] ? arch_local_irq_restore+0x53/0x53 [ 33.138344] ? vsnprintf+0x1ed/0x1900 [ 33.138861] panic+0x1e4/0x41c [ 33.139310] ? refcount_error_report+0x214/0x214 [ 33.139943] ? show_regs_print_info+0x65/0x65 [ 33.140554] ? __warn+0x1a9/0x1e0 [ 33.141030] ? free_kthread_struct+0xa2/0xe0 [ 33.141620] __warn+0x1c4/0x1e0 [ 33.142092] ? free_kthread_struct+0xa2/0xe0 [ 33.142685] report_bug+0x211/0x2d0 [ 33.143198] fixup_bug+0x40/0x90 [ 33.143655] do_trap+0x260/0x390 [ 33.144118] do_error_trap+0x120/0x390 [ 33.144640] ? save_stack+0xa3/0xd0 [ 33.145132] ? do_trap+0x390/0x390 [ 33.145613] ? free_kthread_struct+0xa2/0xe0 [ 33.146213] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.146864] do_invalid_op+0x1b/0x20 [ 33.147366] invalid_op+0x18/0x20 [ 33.147832] RIP: 0010:free_kthread_struct+0xa2/0xe0 [ 33.148497] RSP: 0018:ffff8801db307768 EFLAGS: 00010206 [ 33.149226] RAX: ffff8801bc8f4400 RBX: ffff8801ccd260c0 RCX: ffffffff814937d2 [ 33.150180] RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8801ccd26248 [ 33.151156] RBP: ffff8801db307770 R08: 0000000000000000 R09: 1ffff1003b660ed4 [ 33.152958] R10: ffff8801bc8f4400 R11: 0000000000000001 R12: 1ffff1003b660ef0 [ 33.160194] R13: 1ffff1003b660ef4 R14: 0000000000000000 R15: ffff8801db3077e0 [ 33.167442] ? free_kthread_struct+0xa2/0xe0 [ 33.171824] ? free_kthread_struct+0xa2/0xe0 [ 33.176203] free_task+0x134/0x1a0 executing program executing program [ 33.179715] ? arch_release_task_struct+0x10/0x10 [ 33.184531] ? atomic_notifier_call_chain+0xb9/0x140 [ 33.189604] __put_task_struct+0x229/0x3b0 [ 33.193809] ? free_task+0x1a0/0x1a0 [ 33.197503] delayed_put_task_struct+0xca/0x3d0 [ 33.202141] ? child_wait_callback+0x210/0x210 [ 33.206689] ? put_pid+0x183/0x1f0 [ 33.210197] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.215267] ? task_active_pid_ns+0xd0/0xd0 [ 33.219559] ? trace_hardirqs_on+0xd/0x10 [ 33.223677] ? put_pid+0x1f0/0x1f0 executing program executing program [ 33.227184] ? child_wait_callback+0x210/0x210 [ 33.231736] rcu_process_callbacks+0xd74/0x17d0 [ 33.236383] ? rcu_gp_kthread+0x18e0/0x18e0 [ 33.240673] ? timerqueue_add+0x1e9/0x280 [ 33.244796] ? find_held_lock+0x39/0x1d0 [ 33.248834] ? lock_downgrade+0x990/0x990 [ 33.252956] ? lock_acquire+0x1d5/0x580 [ 33.256900] ? clockevents_program_event+0x163/0x2e0 [ 33.261983] ? rcu_pm_notify+0xc0/0xc0 [ 33.265853] __do_softirq+0x29d/0xbb2 [ 33.269631] ? __irqentry_text_end+0x4/0x4 [ 33.273830] ? do_raw_spin_trylock+0x190/0x190 [ 33.278380] ? do_timer+0x50/0x50 executing program executing program [ 33.281803] ? native_apic_msr_write+0x5c/0x80 [ 33.286351] ? lapic_next_event+0x54/0x80 [ 33.290466] ? clockevents_program_event+0x108/0x2e0 [ 33.295538] ? tick_program_event+0x7f/0xd0 [ 33.299830] ? hrtimer_interrupt+0x489/0x5f0 [ 33.304210] ? rcu_pm_notify+0xc0/0xc0 [ 33.308076] irq_exit+0x1d3/0x210 [ 33.311500] smp_apic_timer_interrupt+0x16b/0x700 [ 33.316306] ? smp_reschedule_interrupt+0xe6/0x670 [ 33.321203] ? smp_call_function_single_interrupt+0x640/0x640 [ 33.327054] ? _raw_spin_lock+0x32/0x40 executing program executing program executing program [ 33.331004] ? handle_edge_irq+0x2b4/0x7c0 [ 33.335206] ? task_prio+0x40/0x40 [ 33.338722] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.343536] ? unlink_anon_vmas+0x5aa/0x9f0 [ 33.347826] apic_timer_interrupt+0x9d/0xb0 [ 33.352111] [ 33.354315] RIP: 0010:kmem_cache_free+0x170/0x280 [ 33.359119] RSP: 0018:ffff8801bc8ff068 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff11 [ 33.366794] RAX: 0000000000000007 RBX: ffff8801ce5967e0 RCX: 0000000000000000 [ 33.374030] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000286 [ 33.381269] RBP: ffff8801bc8ff088 R08: 0000000000000000 R09: 0000000000000000 [ 33.388504] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801dac79680 [ 33.395741] R13: 0000000000000286 R14: ffffffff819e0faa R15: ffff8801ce5967f8 [ 33.402981] ? unlink_anon_vmas+0x5aa/0x9f0 [ 33.407290] unlink_anon_vmas+0x5aa/0x9f0 [ 33.411412] ? page_lock_anon_vma_read+0x6a0/0x6a0 [ 33.416307] ? ___pud_free_tlb+0xdb/0x140 [ 33.420427] ? free_pgd_range+0xb8/0xd90 [ 33.424476] free_pgtables+0xe7/0x330 [ 33.428251] exit_mmap+0x2bf/0x530 [ 33.431760] ? SyS_munmap+0x30/0x30 [ 33.435351] ? __khugepaged_exit+0x42f/0x640 [ 33.439743] ? __might_sleep+0x95/0x190 [ 33.443689] mmput+0x223/0x6c0 [ 33.446850] ? get_task_exe_file+0xc0/0xc0 [ 33.451058] ? is_current_pgrp_orphaned+0xa0/0xa0 [ 33.455865] ? do_exit+0x89b/0x1ad0 [ 33.459459] ? rcu_note_context_switch+0x710/0x710 [ 33.464364] ? do_raw_spin_trylock+0x190/0x190 [ 33.468920] ? down_read+0x96/0x150 [ 33.472511] ? do_exit+0x824/0x1ad0 [ 33.476105] ? __down_interruptible+0x6b0/0x6b0 [ 33.480740] ? _raw_spin_unlock_irqrestore+0x5e/0xba [ 33.485819] do_exit+0x904/0x1ad0 [ 33.489247] ? mm_update_next_owner+0x930/0x930 [ 33.493885] ? trace_hardirqs_on+0xd/0x10 [ 33.498000] ? print_usage_bug+0x480/0x480 [ 33.502220] ? drain_local_pages_wq+0x20/0x20 [ 33.506691] ? check_noncircular+0x20/0x20 [ 33.510898] ? __lock_acquire+0x739/0x4770 [ 33.515115] ? find_held_lock+0x39/0x1d0 [ 33.519152] ? lock_downgrade+0x990/0x990 [ 33.523267] ? recalc_sigpending_tsk+0x117/0x150 [ 33.527991] ? recalc_sigpending+0x103/0x160 [ 33.532367] ? recalc_sigpending_tsk+0x150/0x150 [ 33.537086] ? get_signal+0x2b2/0x16d0 [ 33.540956] do_group_exit+0x149/0x400 [ 33.544813] ? __lock_is_held+0xbc/0x140 [ 33.548841] ? SyS_exit+0x30/0x30 [ 33.552260] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.556722] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.561712] get_signal+0x73f/0x16d0 [ 33.565409] ? ptrace_notify+0x130/0x130 [ 33.569457] ? check_noncircular+0x20/0x20 [ 33.573673] do_signal+0x94/0x1ee0 [ 33.577189] ? lock_downgrade+0x990/0x990 [ 33.581308] ? setup_sigcontext+0x7d0/0x7d0 [ 33.585599] ? kprobe_flush_task+0xe3/0x5d0 [ 33.589897] ? do_raw_spin_trylock+0x190/0x190 [ 33.594457] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.599531] ? trace_hardirqs_on+0xd/0x10 [ 33.603646] ? exit_to_usermode_loop+0x8c/0x310 [ 33.608302] exit_to_usermode_loop+0x214/0x310 [ 33.612852] ? free_unref_page+0x9d0/0x9d0 [ 33.617057] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 33.622563] ? account_kernel_stack+0x155/0x1f0 [ 33.627207] syscall_return_slowpath+0x42f/0x510 [ 33.631936] ? finish_task_switch+0x4eb/0x740 [ 33.636403] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 33.641386] ? preempt_notifier_dec+0x20/0x20 [ 33.645869] ret_from_fork+0x15/0x40 [ 33.649548] RIP: 0033:0x448cd9 [ 33.652703] RSP: 002b:00007f191f922e70 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 [ 33.660378] RAX: 0000000000000000 RBX: 00007f191f923700 RCX: 0000000000448cd9 [ 33.667616] RDX: 00007f191f9239d0 RSI: 00007f191f922e70 RDI: 00000000003d0f00 [ 33.674854] RBP: 00007ffc53717a80 R08: 00007f191f923700 R09: 00007f191f923700 [ 33.682092] R10: 00007f191f9239d0 R11: 0000000000000202 R12: 0000000000000000 [ 33.689337] R13: 00007ffc53717a7f R14: 00007f191f9239c0 R15: 0000000000000000 [ 33.697050] Dumping ftrace buffer: [ 33.700616] (ftrace buffer empty) [ 33.704295] Kernel Offset: disabled [ 33.707892] Rebooting in 86400 seconds..