[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.69' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 51.577468] ------------[ cut here ]------------ [ 51.582459] WARNING: CPU: 0 PID: 6332 at kernel/signal.c:358 task_participate_group_stop+0x1b3/0x210 [ 51.591726] Kernel panic - not syncing: panic_on_warn set ... [ 51.591726] [ 51.599830] CPU: 0 PID: 6332 Comm: file0 Not tainted 4.14.175-syzkaller #0 [ 51.606838] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.616198] Call Trace: [ 51.618863] dump_stack+0x13e/0x194 [ 51.622488] panic+0x1f9/0x42d [ 51.625664] ? add_taint.cold+0x16/0x16 [ 51.629640] ? task_participate_group_stop+0x1b3/0x210 [ 51.634899] ? task_participate_group_stop+0x1b3/0x210 [ 51.640185] __warn.cold+0x2f/0x30 [ 51.643726] ? ist_end_non_atomic+0x10/0x10 [ 51.648034] ? task_participate_group_stop+0x1b3/0x210 [ 51.653306] report_bug+0x20a/0x248 [ 51.656919] do_error_trap+0x195/0x2d0 [ 51.660817] ? math_error+0x2d0/0x2d0 [ 51.664617] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.669462] invalid_op+0x1b/0x40 [ 51.672905] RIP: 0010:task_participate_group_stop+0x1b3/0x210 [ 51.678784] RSP: 0018:ffff88808f8cfbe0 EFLAGS: 00010097 [ 51.684133] RAX: ffff888097cde680 RBX: ffff8880a7a76e00 RCX: ffff8880a7a76e9c [ 51.691385] RDX: 0000000000000000 RSI: 0000000000020000 RDI: ffff888097cde680 [ 51.698634] RBP: 0000000000000000 R08: 0000000000005aab R09: ffffffff8a088dd8 [ 51.705898] R10: ffff888097cdef00 R11: ffff888097cde680 R12: ffff8880a7a76e98 [ 51.713243] R13: ffff88808f8cff58 R14: dffffc0000000000 R15: ffff88808f8cff58 [ 51.720534] do_signal_stop+0x199/0x750 [ 51.724513] get_signal+0xd02/0x1ca0 [ 51.728433] do_signal+0x7c/0x1690 [ 51.731970] ? check_preemption_disabled+0x35/0x240 [ 51.737005] ? setup_sigcontext+0x820/0x820 [ 51.741315] ? putname+0xcd/0x110 [ 51.744757] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 51.750222] ? putname+0xcd/0x110 [ 51.753662] ? rcu_read_lock_sched_held+0x10a/0x130 [ 51.758666] ? kmem_cache_free+0x23a/0x2b0 [ 51.762885] ? putname+0xcd/0x110 [ 51.766324] ? do_execveat_common.isra.0+0x221/0x1c70 [ 51.771626] ? exit_to_usermode_loop+0x41/0x220 [ 51.776283] exit_to_usermode_loop+0x159/0x220 [ 51.780857] do_syscall_64+0x4a3/0x640 [ 51.784759] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 51.789957] RIP: 0033:0x4468d9 [ 51.793164] RSP: 002b:00007f91f8755d98 EFLAGS: 00000246 ORIG_RAX: 000000000000000b [ 51.800856] RAX: ffffffffffffffea RBX: 00000000006dbc58 RCX: 00000000004468d9 [ 51.808112] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 [ 51.815366] RBP: 00000000006dbc50 R08: 00007f91f8756700 R09: 0000000000000000 [ 51.822634] R10: 00007f91f8756700 R11: 0000000000000246 R12: 00000000006dbc5c [ 51.829898] R13: 0000000000000000 R14: 07007ff8464c457f R15: 000000000000f172 [ 51.838912] Kernel Offset: disabled [ 51.842660] Rebooting in 86400 seconds..