[ 34.500947][ T25] audit: type=1800 audit(1572774088.315:25): pid=7085 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.543576][ T25] audit: type=1800 audit(1572774088.315:26): pid=7085 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.565001][ T25] audit: type=1800 audit(1572774088.315:27): pid=7085 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. [ 34.962405][ T7153] sshd (7153) used greatest stack depth: 10136 bytes left [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.26' (ECDSA) to the list of known hosts. 2019/11/03 09:41:36 fuzzer started 2019/11/03 09:41:37 dialing manager at 10.128.0.105:43165 2019/11/03 09:41:38 syscalls: 2554 2019/11/03 09:41:38 code coverage: enabled 2019/11/03 09:41:38 comparison tracing: enabled 2019/11/03 09:41:38 extra coverage: extra coverage is not supported by the kernel 2019/11/03 09:41:38 setuid sandbox: enabled 2019/11/03 09:41:38 namespace sandbox: enabled 2019/11/03 09:41:38 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/03 09:41:38 fault injection: enabled 2019/11/03 09:41:38 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/03 09:41:38 net packet injection: enabled 2019/11/03 09:41:38 net device setup: enabled 2019/11/03 09:41:38 concurrency sanitizer: enabled 2019/11/03 09:41:45 adding functions to KCSAN blacklist: '__nf_conntrack_find_get' '__ext4_new_inode' 'ep_poll' 'update_defense_level' '__splice_from_pipe' 'install_new_memslots' 'tick_do_update_jiffies64' 'do_nanosleep' 'rcu_gp_fqs_loop' 'snd_seq_check_queue' 'ktime_get_real_seconds' 'pipe_poll' 'xas_find_marked' 'tcp_add_backlog' '__tcp_select_window' 'run_timer_softirq' 'tcp_poll' 'generic_permission' '__nf_ct_refresh_acct' 'find_next_bit' '__hrtimer_run_queues' 'task_dump_owner' 'tomoyo_supervisor' 'taskstats_exit' 'echo_char' 'tick_sched_do_timer' syzkaller login: [ 52.497963][ T0] ================================================================== [ 52.506312][ T0] BUG: KCSAN: data-race in mod_timer / timer_clear_idle [ 52.513239][ T0] [ 52.515579][ T0] read to 0xffff88812be1b6e4 of 1 bytes by task 7238 on cpu 1: [ 52.523131][ T0] mod_timer+0x6b5/0x7a0 [ 52.527376][ T0] sk_reset_timer+0x2d/0x70 [ 52.531878][ T0] tcp_rearm_rto.part.0+0x190/0x240 [ 52.537075][ T0] tcp_rearm_rto+0x4f/0x60 [ 52.541493][ T0] tcp_event_new_data_sent+0x1bb/0x1c0 [ 52.546962][ T0] tcp_write_xmit+0xa16/0x3080 [ 52.551722][ T0] __tcp_push_pending_frames+0x7b/0x1d0 [ 52.557324][ T0] tcp_push+0x1e9/0x3d0 [ 52.561481][ T0] tcp_sendmsg_locked+0x1d1e/0x1f30 [ 52.566677][ T0] tcp_sendmsg+0x39/0x60 [ 52.570920][ T0] inet_sendmsg+0x6d/0x90 [ 52.575250][ T0] sock_sendmsg+0x9f/0xc0 [ 52.579579][ T0] sock_write_iter+0x16b/0x210 [ 52.584346][ T0] new_sync_write+0x388/0x4a0 [ 52.589015][ T0] [ 52.591348][ T0] write to 0xffff88812be1b6e4 of 1 bytes by task 0 on cpu 0: [ 52.598723][ T0] timer_clear_idle+0x42/0x50 [ 52.603401][ T0] tick_nohz_next_event+0x164/0x380 [ 52.608608][ T0] tick_nohz_idle_stop_tick+0x3c2/0x670 [ 52.614163][ T0] do_idle+0x1a5/0x280 [ 52.618239][ T0] cpu_startup_entry+0x1b/0x20 [ 52.623003][ T0] rest_init+0xec/0xf6 [ 52.627072][ T0] arch_call_rest_init+0x17/0x37 [ 52.632011][ T0] start_kernel+0x838/0x85e [ 52.636518][ T0] x86_64_start_reservations+0x29/0x2b [ 52.642139][ T0] x86_64_start_kernel+0x72/0x76 [ 52.647199][ T0] secondary_startup_64+0xa4/0xb0 [ 52.652223][ T0] [ 52.654570][ T0] Reported by Kernel Concurrency Sanitizer on: [ 52.660754][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0 [ 52.667870][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.677938][ T0] ================================================================== [ 52.686071][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 52.692706][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0 [ 52.699795][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.709831][ T0] Call Trace: [ 52.713114][ T0] dump_stack+0xf5/0x159 [ 52.717403][ T0] panic+0x210/0x640 [ 52.721288][ T0] ? x86_64_start_reservations+0x29/0x2b [ 52.726901][ T0] ? vprintk_func+0x8d/0x140 [ 52.731477][ T0] kcsan_report.cold+0xc/0x10 [ 52.736224][ T0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 52.741868][ T0] __tsan_write1+0x32/0x40 [ 52.746398][ T0] timer_clear_idle+0x42/0x50 [ 52.751059][ T0] tick_nohz_next_event+0x164/0x380 [ 52.756242][ T0] tick_nohz_idle_stop_tick+0x3c2/0x670 [ 52.761857][ T0] ? __tsan_read4+0x2c/0x30 [ 52.766502][ T0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.772728][ T0] do_idle+0x1a5/0x280 [ 52.776834][ T0] ? do_idle+0xe7/0x280 [ 52.780977][ T0] cpu_startup_entry+0x1b/0x20 [ 52.785750][ T0] rest_init+0xec/0xf6 [ 52.789805][ T0] ? trace_event_define_fields_vector_free_moved+0xce/0xce [ 52.797008][ T0] arch_call_rest_init+0x17/0x37 [ 52.801928][ T0] start_kernel+0x838/0x85e [ 52.806414][ T0] x86_64_start_reservations+0x29/0x2b [ 52.811862][ T0] x86_64_start_kernel+0x72/0x76 [ 52.816812][ T0] secondary_startup_64+0xa4/0xb0 [ 52.823211][ T0] Kernel Offset: disabled [ 52.827567][ T0] Rebooting in 86400 seconds..