[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.618158][ T25] audit: type=1800 audit(1572279554.448:25): pid=6998 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.645296][ T25] audit: type=1800 audit(1572279554.458:26): pid=6998 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.680951][ T25] audit: type=1800 audit(1572279554.458:27): pid=6998 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 '10.128.1.32' (ECDSA) to the list of known hosts. 2019/10/28 16:19:25 fuzzer started 2019/10/28 16:19:26 dialing manager at 10.128.0.105:45117 2019/10/28 16:19:27 syscalls: 2540 2019/10/28 16:19:27 code coverage: enabled 2019/10/28 16:19:27 comparison tracing: enabled 2019/10/28 16:19:27 extra coverage: extra coverage is not supported by the kernel 2019/10/28 16:19:27 setuid sandbox: enabled 2019/10/28 16:19:27 namespace sandbox: enabled 2019/10/28 16:19:27 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/28 16:19:27 fault injection: enabled 2019/10/28 16:19:27 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/28 16:19:27 net packet injection: enabled 2019/10/28 16:19:27 net device setup: enabled 2019/10/28 16:19:27 concurrency sanitizer: enabled syzkaller login: [ 52.412449][ T7162] KCSAN: could not find function: 'poll_schedule_timeout' 2019/10/28 16:19:33 adding functions to KCSAN blacklist: '__nf_ct_refresh_acct' 'find_next_bit' 'run_timer_softirq' 'tcp_add_backlog' 'tick_sched_do_timer' 'ep_poll' 'ktime_get_real_seconds' 'ext4_free_inode' 'ext4_free_inodes_count' 'ext4_nonda_switch' '__hrtimer_run_queues' 'rcu_gp_fqs_loop' '__tcp_select_window' 'echo_char' 'task_dump_owner' 'do_syslog' 'do_nanosleep' 'tcp_poll' 'pid_update_inode' 'poll_schedule_timeout' '__nf_conntrack_find_get' 'tomoyo_supervisor' 'tick_do_update_jiffies64' 'blk_mq_sched_dispatch_requests' [ 58.281249][ T7146] ================================================================== [ 58.289380][ T7146] BUG: KCSAN: data-race in mod_timer / timer_clear_idle [ 58.296462][ T7146] [ 58.298788][ T7146] write to 0xffff88812be1b6e4 of 1 bytes by task 0 on cpu 0: [ 58.306170][ T7146] timer_clear_idle+0x42/0x50 [ 58.310837][ T7146] __tick_nohz_idle_restart_tick+0x36/0x1b0 [ 58.316742][ T7146] tick_nohz_idle_exit+0x1af/0x1e0 [ 58.321847][ T7146] do_idle+0xb1/0x280 [ 58.325822][ T7146] cpu_startup_entry+0x1b/0x20 [ 58.330569][ T7146] rest_init+0xec/0xf6 [ 58.334634][ T7146] arch_call_rest_init+0x17/0x37 [ 58.339553][ T7146] start_kernel+0x838/0x85e [ 58.344042][ T7146] x86_64_start_reservations+0x29/0x2b [ 58.349500][ T7146] x86_64_start_kernel+0x72/0x76 [ 58.354423][ T7146] secondary_startup_64+0xa4/0xb0 [ 58.359433][ T7146] [ 58.361758][ T7146] read to 0xffff88812be1b6e4 of 1 bytes by task 7146 on cpu 1: [ 58.369310][ T7146] mod_timer+0x50d/0x7a0 [ 58.373549][ T7146] sk_reset_timer+0x2d/0x70 [ 58.378037][ T7146] tcp_rearm_rto.part.0+0x190/0x240 [ 58.383219][ T7146] tcp_rearm_rto+0x4f/0x60 [ 58.387622][ T7146] tcp_event_new_data_sent+0x1bb/0x1c0 [ 58.393079][ T7146] tcp_write_xmit+0xa16/0x3080 [ 58.397830][ T7146] __tcp_push_pending_frames+0x7b/0x1d0 [ 58.403366][ T7146] tcp_push+0x1e9/0x3d0 [ 58.407509][ T7146] tcp_sendmsg_locked+0x1d1e/0x1f30 [ 58.412704][ T7146] tcp_sendmsg+0x39/0x60 [ 58.416930][ T7146] inet_sendmsg+0x6d/0x90 [ 58.421262][ T7146] sock_sendmsg+0x9f/0xc0 [ 58.425579][ T7146] sock_write_iter+0x16b/0x210 [ 58.430319][ T7146] [ 58.432630][ T7146] Reported by Kernel Concurrency Sanitizer on: [ 58.438774][ T7146] CPU: 1 PID: 7146 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 58.446210][ T7146] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.456248][ T7146] ================================================================== [ 58.464300][ T7146] Kernel panic - not syncing: panic_on_warn set ... [ 58.470897][ T7146] CPU: 1 PID: 7146 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 58.478334][ T7146] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.488394][ T7146] Call Trace: [ 58.491684][ T7146] dump_stack+0xf5/0x159 [ 58.495953][ T7146] panic+0x210/0x640 [ 58.499886][ T7146] ? tcp_sendmsg_locked+0x1d1e/0x1f30 [ 58.505344][ T7146] ? vprintk_func+0x8d/0x140 [ 58.509927][ T7146] kcsan_report.cold+0xc/0x10 [ 58.514765][ T7146] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 58.520302][ T7146] __tsan_read1+0x2c/0x30 [ 58.524625][ T7146] mod_timer+0x50d/0x7a0 [ 58.528858][ T7146] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 58.534645][ T7146] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 58.540300][ T7146] sk_reset_timer+0x2d/0x70 [ 58.544836][ T7146] tcp_rearm_rto.part.0+0x190/0x240 [ 58.550027][ T7146] tcp_rearm_rto+0x4f/0x60 [ 58.554432][ T7146] tcp_event_new_data_sent+0x1bb/0x1c0 [ 58.559880][ T7146] tcp_write_xmit+0xa16/0x3080 [ 58.564644][ T7146] ? kmem_cache_alloc_node_trace+0x273/0x670 [ 58.570638][ T7146] __tcp_push_pending_frames+0x7b/0x1d0 [ 58.576174][ T7146] tcp_push+0x1e9/0x3d0 [ 58.580508][ T7146] tcp_sendmsg_locked+0x1d1e/0x1f30 [ 58.585711][ T7146] tcp_sendmsg+0x39/0x60 [ 58.589941][ T7146] inet_sendmsg+0x6d/0x90 [ 58.594255][ T7146] ? inet_send_prepare+0x200/0x200 [ 58.599353][ T7146] sock_sendmsg+0x9f/0xc0 [ 58.603692][ T7146] sock_write_iter+0x16b/0x210 [ 58.608458][ T7146] new_sync_write+0x388/0x4a0 [ 58.613132][ T7146] __vfs_write+0xb1/0xc0 [ 58.617379][ T7146] vfs_write+0x18a/0x390 [ 58.621626][ T7146] ksys_write+0xd5/0x1b0 [ 58.625861][ T7146] __x64_sys_write+0x4c/0x60 [ 58.630444][ T7146] do_syscall_64+0xcc/0x370 [ 58.634950][ T7146] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 58.640827][ T7146] RIP: 0033:0x47c530 [ 58.644733][ T7146] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 58.664322][ T7146] RSP: 002b:000000c4210cf4f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000001 [ 58.672722][ T7146] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 58.680692][ T7146] RDX: 0000000000000008 RSI: 000000c4202d2020 RDI: 0000000000000003 [ 58.688658][ T7146] RBP: 000000c4210cf550 R08: 0000000000000000 R09: 0000000000000000 [ 58.696626][ T7146] R10: 0000000000000000 R11: 0000000000000216 R12: 000000c4200b3b00 [ 58.704588][ T7146] R13: 0000000000000007 R14: 0000000000c1d600 R15: 0000000000001940 [ 59.839228][ T7146] Shutting down cpus with NMI [ 59.845161][ T7146] Kernel Offset: disabled [ 59.849485][ T7146] Rebooting in 86400 seconds..