[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c.
[   37.747615][   T26] audit: type=1800 audit(1572090544.284:25): pid=7043 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[   37.767454][   T26] audit: type=1800 audit(1572090544.284:26): pid=7043 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[   37.796024][   T26] audit: type=1800 audit(1572090544.284:27): pid=7043 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 '10.128.0.60' (ECDSA) to the list of known hosts.
2019/10/26 11:49:15 fuzzer started
2019/10/26 11:49:17 dialing manager at 10.128.0.105:33655
2019/10/26 11:49:17 syscalls: 2533
2019/10/26 11:49:17 code coverage: enabled
2019/10/26 11:49:17 comparison tracing: enabled
2019/10/26 11:49:17 extra coverage: extra coverage is not supported by the kernel
2019/10/26 11:49:17 setuid sandbox: enabled
2019/10/26 11:49:17 namespace sandbox: enabled
2019/10/26 11:49:17 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/26 11:49:17 fault injection: enabled
2019/10/26 11:49:17 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/26 11:49:17 net packet injection: enabled
2019/10/26 11:49:17 net device setup: enabled
2019/10/26 11:49:17 concurrency sanitizer: enabled
2019/10/26 11:49:21 adding functions to KCSAN blacklist: 'find_next_bit' '__ext4_new_inode' '__nf_conntrack_find_get' 'ep_poll' 'tomoyo_supervisor' 'pipe_poll' 'rcu_gp_fqs_check_wake' '__nf_ct_refresh_acct' 'add_timer' 'taskstats_exit' 'pid_update_inode' 'tcp_poll' 'find_get_pages_range_tag' 'generic_permission' '__hrtimer_run_queues' 'tcp_add_backlog' 'ktime_get_real_seconds' 'do_nanosleep' 
syzkaller login: [   58.739202][    T0] ==================================================================
[   58.747466][    T0] BUG: KCSAN: data-race in mod_timer / timer_clear_idle
[   58.754371][    T0] 
[   58.756710][    T0] read to 0xffff88812bf1b6e4 of 1 bytes by task 7213 on cpu 0:
[   58.764232][    T0]  mod_timer+0x50d/0x7a0
[   58.768455][    T0]  sk_reset_timer+0x2d/0x70
[   58.773108][    T0]  tcp_rearm_rto.part.0+0x190/0x240
[   58.778361][    T0]  tcp_rearm_rto+0x4f/0x60
[   58.782758][    T0]  tcp_event_new_data_sent+0x1bb/0x1c0
[   58.788208][    T0]  tcp_write_xmit+0xa16/0x3080
[   58.793053][    T0]  __tcp_push_pending_frames+0x7b/0x1d0
[   58.798597][    T0]  tcp_push+0x1e9/0x3d0
[   58.802758][    T0]  tcp_sendmsg_locked+0x1d1e/0x1f30
[   58.807999][    T0]  tcp_sendmsg+0x39/0x60
[   58.812239][    T0]  inet_sendmsg+0x6d/0x90
[   58.816568][    T0]  sock_sendmsg+0x9f/0xc0
[   58.820963][    T0]  sock_write_iter+0x16b/0x210
[   58.825704][    T0]  new_sync_write+0x388/0x4a0
[   58.830351][    T0] 
[   58.832661][    T0] write to 0xffff88812bf1b6e4 of 1 bytes by task 0 on cpu 1:
[   58.840010][    T0]  timer_clear_idle+0x42/0x50
[   58.844666][    T0]  __tick_nohz_idle_restart_tick+0x36/0x1b0
[   58.850535][    T0]  tick_nohz_idle_exit+0x1af/0x1e0
[   58.855630][    T0]  do_idle+0xb1/0x280
[   58.859588][    T0]  cpu_startup_entry+0x1b/0x20
[   58.864333][    T0]  start_secondary+0x208/0x260
[   58.869076][    T0]  secondary_startup_64+0xa4/0xb0
[   58.874068][    T0] 
[   58.876382][    T0] Reported by Kernel Concurrency Sanitizer on:
[   58.882514][    T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0
[   58.889596][    T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   58.899630][    T0] ==================================================================
[   58.907686][    T0] Kernel panic - not syncing: panic_on_warn set ...
[   58.914258][    T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0
[   58.921346][    T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   58.931395][    T0] Call Trace:
[   58.934676][    T0]  dump_stack+0xf5/0x159
[   58.938895][    T0]  panic+0x210/0x640
[   58.942771][    T0]  ? vprintk_func+0x8d/0x140
[   58.947341][    T0]  kcsan_report.cold+0xc/0x10
[   58.952025][    T0]  __kcsan_setup_watchpoint+0x32e/0x4a0
[   58.957551][    T0]  __tsan_write1+0x32/0x40
[   58.961947][    T0]  timer_clear_idle+0x42/0x50
[   58.966610][    T0]  __tick_nohz_idle_restart_tick+0x36/0x1b0
[   58.972486][    T0]  tick_nohz_idle_exit+0x1af/0x1e0
[   58.977686][    T0]  do_idle+0xb1/0x280
[   58.981651][    T0]  cpu_startup_entry+0x1b/0x20
[   58.986436][    T0]  start_secondary+0x208/0x260
[   58.991195][    T0]  secondary_startup_64+0xa4/0xb0
[   58.997557][    T0] Kernel Offset: disabled
[   59.002140][    T0] Rebooting in 86400 seconds..