[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c.
[   34.790047][   T26] audit: type=1800 audit(1572870155.001:25): pid=7028 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[   34.836566][   T26] audit: type=1800 audit(1572870155.001:26): pid=7028 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[   34.862195][   T26] audit: type=1800 audit(1572870155.001:27): pid=7028 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0
[....] 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 '10.128.0.107' (ECDSA) to the list of known hosts.
2019/11/04 12:22:43 fuzzer started
2019/11/04 12:22:45 dialing manager at 10.128.0.105:43623
2019/11/04 12:22:46 syscalls: 2553
2019/11/04 12:22:46 code coverage: enabled
2019/11/04 12:22:46 comparison tracing: enabled
2019/11/04 12:22:46 extra coverage: extra coverage is not supported by the kernel
2019/11/04 12:22:46 setuid sandbox: enabled
2019/11/04 12:22:46 namespace sandbox: enabled
2019/11/04 12:22:46 Android sandbox: /sys/fs/selinux/policy does not exist
2019/11/04 12:22:46 fault injection: enabled
2019/11/04 12:22:46 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/11/04 12:22:46 net packet injection: enabled
2019/11/04 12:22:46 net device setup: enabled
2019/11/04 12:22:46 concurrency sanitizer: enabled
2019/11/04 12:22:46 devlink PCI setup: PCI device 0000:00:10.0 is not available
2019/11/04 12:22:52 adding functions to KCSAN blacklist: '__nf_conntrack_find_get' 'echo_char' 'ext4_free_inode' 'ext4_has_free_clusters' '__ext4_new_inode' 'tick_nohz_idle_stop_tick' 'wbt_done' '__hrtimer_run_queues' 'find_next_bit' 'ep_poll' 'ktime_get_real_seconds' 'taskstats_exit' 'tick_do_update_jiffies64' 'run_timer_softirq' 'generic_permission' 'add_timer' 'rcu_gp_fqs_loop' 'ext4_setattr' 'tomoyo_supervisor' '__tcp_select_window' 'tcp_poll' 'tcp_add_backlog' 'pid_update_inode' '__nf_ct_refresh_acct' 'rcu_gp_fqs_check_wake' 'pipe_poll' 'do_nanosleep' 'tick_sched_do_timer' 'kauditd_thread' 'ktime_get_seconds' 'generic_fillattr' 'task_dump_owner' 'dd_has_work' 'find_get_pages_range_tag' 'generic_write_end' 
syzkaller login: [   67.167864][    T0] ==================================================================
[   67.176024][    T0] BUG: KCSAN: data-race in mod_timer / timer_clear_idle
[   67.182942][    T0] 
[   67.185251][    T0] read to 0xffff88812be1b6e4 of 1 bytes by task 7182 on cpu 1:
[   67.192809][    T0]  mod_timer+0x50d/0x7a0
[   67.197079][    T0]  sk_reset_timer+0x2d/0x70
[   67.201586][    T0]  tcp_rearm_rto.part.0+0x190/0x240
[   67.206814][    T0]  tcp_rearm_rto+0x4f/0x60
[   67.211227][    T0]  tcp_event_new_data_sent+0x1bb/0x1c0
[   67.216683][    T0]  tcp_write_xmit+0xa16/0x3080
[   67.221454][    T0]  __tcp_push_pending_frames+0x7b/0x1d0
[   67.227005][    T0]  tcp_push+0x1e9/0x3d0
[   67.231170][    T0]  tcp_sendmsg_locked+0x1d1e/0x1f30
[   67.236406][    T0]  tcp_sendmsg+0x39/0x60
[   67.240656][    T0]  inet_sendmsg+0x6d/0x90
[   67.244974][    T0]  sock_sendmsg+0x9f/0xc0
[   67.249317][    T0]  sock_write_iter+0x16b/0x210
[   67.254074][    T0]  new_sync_write+0x388/0x4a0
[   67.258729][    T0] 
[   67.261055][    T0] write to 0xffff88812be1b6e4 of 1 bytes by task 0 on cpu 0:
[   67.268418][    T0]  timer_clear_idle+0x42/0x50
[   67.273097][    T0]  __tick_nohz_idle_restart_tick+0x36/0x1b0
[   67.278983][    T0]  tick_nohz_idle_exit+0x1af/0x1e0
[   67.284100][    T0]  do_idle+0xb1/0x280
[   67.288081][    T0]  cpu_startup_entry+0x1b/0x20
[   67.292838][    T0]  rest_init+0xec/0xf6
[   67.296903][    T0]  arch_call_rest_init+0x17/0x37
[   67.301835][    T0]  start_kernel+0x838/0x85e
[   67.306330][    T0]  x86_64_start_reservations+0x29/0x2b
[   67.311783][    T0]  x86_64_start_kernel+0x72/0x76
[   67.316716][    T0]  secondary_startup_64+0xa4/0xb0
[   67.321725][    T0] 
[   67.324034][    T0] Reported by Kernel Concurrency Sanitizer on:
[   67.330189][    T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[   67.337284][    T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   67.347329][    T0] ==================================================================
[   67.355394][    T0] Kernel panic - not syncing: panic_on_warn set ...
[   67.361999][    T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[   67.369098][    T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   67.379145][    T0] Call Trace:
[   67.382417][    T0]  dump_stack+0xf5/0x159
[   67.386768][    T0]  panic+0x210/0x640
[   67.390673][    T0]  ? x86_64_start_reservations+0x29/0x2b
[   67.396312][    T0]  ? vprintk_func+0x8d/0x140
[   67.400902][    T0]  kcsan_report.cold+0xc/0x10
[   67.405580][    T0]  __kcsan_setup_watchpoint+0x32e/0x4a0
[   67.411137][    T0]  __tsan_write1+0x32/0x40
[   67.415561][    T0]  timer_clear_idle+0x42/0x50
[   67.420239][    T0]  __tick_nohz_idle_restart_tick+0x36/0x1b0
[   67.426121][    T0]  tick_nohz_idle_exit+0x1af/0x1e0
[   67.431223][    T0]  do_idle+0xb1/0x280
[   67.435208][    T0]  cpu_startup_entry+0x1b/0x20
[   67.439965][    T0]  rest_init+0xec/0xf6
[   67.444033][    T0]  ? trace_event_define_fields_vector_free_moved+0xce/0xce
[   67.451224][    T0]  arch_call_rest_init+0x17/0x37
[   67.456158][    T0]  start_kernel+0x838/0x85e
[   67.460645][    T0]  x86_64_start_reservations+0x29/0x2b
[   67.466084][    T0]  x86_64_start_kernel+0x72/0x76
[   67.471002][    T0]  secondary_startup_64+0xa4/0xb0
[   67.477154][    T0] Kernel Offset: disabled
[   67.481518][    T0] Rebooting in 86400 seconds..