[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.978359][ T26] audit: type=1800 audit(1572092963.253:25): pid=7151 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 40.999259][ T26] audit: type=1800 audit(1572092963.253:26): pid=7151 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 41.028852][ T26] audit: type=1800 audit(1572092963.253:27): pid=7151 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 '10.128.0.131' (ECDSA) to the list of known hosts. 2019/10/26 12:29:35 fuzzer started 2019/10/26 12:29:37 dialing manager at 10.128.0.105:33655 2019/10/26 12:29:39 syscalls: 2533 2019/10/26 12:29:39 code coverage: enabled 2019/10/26 12:29:39 comparison tracing: enabled 2019/10/26 12:29:39 extra coverage: extra coverage is not supported by the kernel 2019/10/26 12:29:39 setuid sandbox: enabled 2019/10/26 12:29:39 namespace sandbox: enabled 2019/10/26 12:29:39 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/26 12:29:39 fault injection: enabled 2019/10/26 12:29:39 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/26 12:29:39 net packet injection: enabled 2019/10/26 12:29:39 net device setup: enabled 2019/10/26 12:29:39 concurrency sanitizer: enabled syzkaller login: [ 66.425458][ T7319] KCSAN: could not find function: 'poll_schedule_timeout' 2019/10/26 12:29:52 adding functions to KCSAN blacklist: '__hrtimer_run_queues' 'do_nanosleep' 'tick_do_update_jiffies64' 'task_dump_owner' '__skb_try_recv_from_queue' 'blk_mq_get_request' '__ext4_new_inode' 'ep_poll' 'kvm_arch_vcpu_load' 'update_defense_level' 'ktime_get_seconds' 'ext4_mb_good_group' 'blk_mq_dispatch_rq_list' '__snd_rawmidi_transmit_ack' 'rcu_gp_fqs_check_wake' 'taskstats_exit' 'get_task_cred' 'vm_area_dup' 'ext4_free_inode' 'ext4_free_inodes_count' 'ext4_nonda_switch' 'pid_update_inode' 'tcp_poll' 'find_get_pages_range_tag' 'mod_timer' 'generic_write_end' 'commit_echoes' 'tcp_add_backlog' 'ktime_get_real_seconds' '__delete_from_page_cache' 'p9_poll_workfn' 'wbt_done' 'sit_tunnel_xmit' 'find_next_bit' '__nf_conntrack_find_get' 'shmem_file_read_iter' 'ext4_has_free_clusters' 'poll_schedule_timeout' 'run_timer_softirq' 'vti_tunnel_xmit' 'xas_clear_mark' 'tomoyo_supervisor' 'pipe_poll' '__nf_ct_refresh_acct' 'add_timer' 'common_perm_cond' 'dd_has_work' 'generic_permission' 'rcu_gp_fqs_loop' 'tick_sched_do_timer' 'datagram_poll' 'pcpu_alloc' [ 144.984896][ T0] ================================================================== [ 144.993044][ T0] BUG: KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_next_event [ 145.001606][ T0] [ 145.003919][ T0] write to 0xffffffff85cb2790 of 4 bytes by task 0 on cpu 0: [ 145.011273][ T0] tick_nohz_idle_stop_tick+0x525/0x670 [ 145.017058][ T0] do_idle+0x1a5/0x280 [ 145.021105][ T0] cpu_startup_entry+0x1b/0x20 [ 145.025848][ T0] rest_init+0xec/0xf6 [ 145.030011][ T0] arch_call_rest_init+0x17/0x37 [ 145.034984][ T0] start_kernel+0x838/0x85e [ 145.039468][ T0] x86_64_start_reservations+0x29/0x2b [ 145.044929][ T0] x86_64_start_kernel+0x72/0x76 [ 145.049967][ T0] secondary_startup_64+0xa4/0xb0 [ 145.054963][ T0] [ 145.057273][ T0] read to 0xffffffff85cb2790 of 4 bytes by task 0 on cpu 1: [ 145.064566][ T0] tick_nohz_next_event+0x1a4/0x380 [ 145.069747][ T0] tick_nohz_idle_stop_tick+0x3c2/0x670 [ 145.075269][ T0] do_idle+0x1a5/0x280 [ 145.079313][ T0] cpu_startup_entry+0x1b/0x20 [ 145.084064][ T0] start_secondary+0x208/0x260 [ 145.088816][ T0] secondary_startup_64+0xa4/0xb0 [ 145.093807][ T0] [ 145.096120][ T0] Reported by Kernel Concurrency Sanitizer on: [ 145.102250][ T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0 [ 145.109343][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 145.119371][ T0] ================================================================== [ 145.127593][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 145.134175][ T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0 [ 145.141277][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 145.151310][ T0] Call Trace: [ 145.154635][ T0] dump_stack+0xf5/0x159 [ 145.158906][ T0] panic+0x210/0x640 [ 145.162787][ T0] ? vprintk_func+0x8d/0x140 [ 145.167417][ T0] kcsan_report.cold+0xc/0x10 [ 145.172079][ T0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 145.177618][ T0] __tsan_read4+0x2c/0x30 [ 145.182035][ T0] tick_nohz_next_event+0x1a4/0x380 [ 145.187215][ T0] tick_nohz_idle_stop_tick+0x3c2/0x670 [ 145.192753][ T0] ? __tsan_read4+0x2c/0x30 [ 145.197234][ T0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 145.203453][ T0] do_idle+0x1a5/0x280 [ 145.207511][ T0] cpu_startup_entry+0x1b/0x20 [ 145.212269][ T0] start_secondary+0x208/0x260 [ 145.217027][ T0] secondary_startup_64+0xa4/0xb0 [ 145.223636][ T0] Kernel Offset: disabled [ 145.227974][ T0] Rebooting in 86400 seconds..