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-mmots-kasan-gce-7,10.128.0.45' (ECDSA) to the list of known hosts. 2017/11/06 02:04:12 parsed 1 programs 2017/11/06 02:04:12 executed programs: 0 syzkaller login: [ 42.893311] ------------[ cut here ]------------ [ 42.894055] WARNING: CPU: 0 PID: 2998 at kernel/signal.c:340 task_participate_group_stop+0x1ce/0x230 [ 42.895298] Kernel panic - not syncing: panic_on_warn set ... [ 42.895298] [ 42.896268] CPU: 0 PID: 2998 Comm: syz-executor0 Not tainted 4.14.0-rc5-mm1+ #20 [ 42.897272] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.898503] Call Trace: [ 42.898861] dump_stack+0x194/0x257 [ 42.899418] ? arch_local_irq_restore+0x53/0x53 [ 42.900106] ? vsnprintf+0x1ed/0x1900 [ 42.900624] panic+0x1e4/0x41c [ 42.901061] ? refcount_error_report+0x214/0x214 [ 42.901692] ? show_regs_print_info+0x65/0x65 [ 42.902315] ? __warn+0x1a9/0x1e0 [ 42.902784] ? task_participate_group_stop+0x1ce/0x230 [ 42.903481] __warn+0x1c4/0x1e0 [ 42.903971] ? task_participate_group_stop+0x1ce/0x230 [ 42.904765] report_bug+0x211/0x2d0 [ 42.905261] fixup_bug+0x40/0x90 [ 42.905719] do_trap+0x260/0x390 [ 42.906180] do_error_trap+0x120/0x390 [ 42.906702] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 42.907381] ? do_trap+0x390/0x390 [ 42.907859] ? task_participate_group_stop+0x1ce/0x230 [ 42.908636] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.909300] do_invalid_op+0x1b/0x20 [ 42.909797] invalid_op+0x18/0x20 [ 42.910262] RIP: 0010:task_participate_group_stop+0x1ce/0x230 [ 42.911072] RSP: 0018:ffff8801d1ce78b8 EFLAGS: 00010093 [ 42.911800] RAX: ffff8801d1d50000 RBX: ffff8801d1d50000 RCX: ffffffff8143bf6e [ 42.912750] RDX: 0000000000000000 RSI: 0000000000060013 RDI: ffff8801d1d50480 [ 42.915887] RBP: ffff8801d1ce78d0 R08: ffffffff81441b7c R09: 000000000000000c [ 42.923122] R10: ffff8801d1ce77b0 R11: 0000000000000000 R12: ffff8801d1c88200 [ 42.930362] R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8801d1d50578 [ 42.937609] ? ptrace_stop+0x5bc/0xa40 [ 42.941461] ? task_participate_group_stop+0x1ce/0x230 [ 42.946709] ? task_participate_group_stop+0x1ce/0x230 [ 42.951948] ? do_signal_stop+0x486/0x910 [ 42.956062] do_signal_stop+0x217/0x910 [ 42.960007] ? ptrace_do_notify+0x310/0x310 [ 42.964296] ? __lock_is_held+0xb6/0x140 [ 42.968336] get_signal+0x55a/0x16d0 [ 42.972024] ? ptrace_notify+0x130/0x130 [ 42.976053] ? trace_hardirqs_on+0xd/0x10 [ 42.980170] ? hrtimer_try_to_cancel+0x9a/0x5c0 [ 42.984806] ? __hrtimer_get_remaining+0x1c0/0x1c0 [ 42.989704] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 42.995554] ? check_noncircular+0x20/0x20 [ 42.999756] ? rcu_note_context_switch+0x710/0x710 [ 43.004654] do_signal+0x94/0x1ee0 [ 43.008167] ? __might_sleep+0x95/0x190 [ 43.012112] ? do_nanosleep+0x4f9/0x6e0 [ 43.016054] ? setup_sigcontext+0x7d0/0x7d0 [ 43.020339] ? schedule_timeout_idle+0x90/0x90 [ 43.024894] ? rcu_pm_notify+0xc0/0xc0 [ 43.028759] ? hrtimer_nanosleep+0x2cc/0x860 [ 43.033132] ? SyS_waitid+0x50/0x50 [ 43.036726] ? exit_to_usermode_loop+0x8c/0x310 [ 43.041366] exit_to_usermode_loop+0x214/0x310 [ 43.045914] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 43.051421] ? __hrtimer_init+0x140/0x140 [ 43.055540] syscall_return_slowpath+0x42f/0x510 [ 43.060261] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 43.065242] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 43.070144] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 43.075124] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 43.079851] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 43.084571] RIP: 0033:0x47deb0 [ 43.087725] RSP: 002b:0000000000a6fa08 EFLAGS: 00000246 ORIG_RAX: 0000000000000023 [ 43.095396] RAX: fffffffffffffdfc RBX: 000000000155e914 RCX: 000000000047deb0 [ 43.102629] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000a6fa10 [ 43.109863] RBP: 0000000000000002 R08: 0000000000000001 R09: 000000000155e940 [ 43.117098] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 43.124334] R13: 0000000000000004 R14: 000000000000a77b R15: 0000000000000016