[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.102871][ T23] audit: type=1800 audit(1570562449.715:25): pid=7162 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.155551][ T23] audit: type=1800 audit(1570562449.715:26): pid=7162 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.185245][ T23] audit: type=1800 audit(1570562449.715:27): pid=7162 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 '10.128.1.51' (ECDSA) to the list of known hosts. 2019/10/08 19:20:56 fuzzer started 2019/10/08 19:20:58 dialing manager at 10.128.0.105:35069 2019/10/08 19:20:58 syscalls: 2523 2019/10/08 19:20:58 code coverage: enabled 2019/10/08 19:20:58 comparison tracing: enabled 2019/10/08 19:20:58 extra coverage: extra coverage is not supported by the kernel 2019/10/08 19:20:58 setuid sandbox: enabled 2019/10/08 19:20:58 namespace sandbox: enabled 2019/10/08 19:20:58 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/08 19:20:58 fault injection: enabled 2019/10/08 19:20:58 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/08 19:20:58 net packet injection: enabled 2019/10/08 19:20:58 net device setup: enabled 2019/10/08 19:20:58 concurrency sanitizer: enabled syzkaller login: [ 44.026744][ T10] ================================================================== [ 44.034898][ T10] BUG: KCSAN: data-race in rcu_gp_fqs_check_wake / rcu_preempt_deferred_qs_irqrestore [ 44.044408][ T10] [ 44.046719][ T10] write to 0xffffffff85a7f190 of 8 bytes by task 7317 on cpu 0: [ 44.054329][ T10] rcu_preempt_deferred_qs_irqrestore+0x43d/0x580 [ 44.060719][ T10] rcu_read_unlock_special+0xec/0x370 [ 44.066091][ T10] __rcu_read_unlock+0xcf/0xe0 [ 44.070837][ T10] __ip_queue_xmit+0x3b0/0xa40 [ 44.075578][ T10] ip_queue_xmit+0x45/0x60 [ 44.079973][ T10] __tcp_transmit_skb+0xdeb/0x1cd0 [ 44.085060][ T10] __tcp_send_ack+0x246/0x300 [ 44.089730][ T10] tcp_send_ack+0x34/0x40 [ 44.094051][ T10] tcp_cleanup_rbuf+0x130/0x360 [ 44.098894][ T10] tcp_recvmsg+0x633/0x1a30 [ 44.103393][ T10] inet_recvmsg+0xbb/0x250 [ 44.107797][ T10] sock_recvmsg+0x92/0xb0 [ 44.112108][ T10] sock_read_iter+0x15f/0x1e0 [ 44.116769][ T10] new_sync_read+0x389/0x4f0 [ 44.121331][ T10] [ 44.123643][ T10] read to 0xffffffff85a7f190 of 8 bytes by task 10 on cpu 1: [ 44.130988][ T10] rcu_gp_fqs_check_wake+0x93/0xd0 [ 44.136088][ T10] rcu_gp_fqs_loop+0x36c/0x580 [ 44.140838][ T10] rcu_gp_kthread+0x143/0x220 [ 44.145501][ T10] kthread+0x1d4/0x200 [ 44.149556][ T10] ret_from_fork+0x1f/0x30 [ 44.153940][ T10] [ 44.156240][ T10] Reported by Kernel Concurrency Sanitizer on: [ 44.162369][ T10] CPU: 1 PID: 10 Comm: rcu_preempt Not tainted 5.3.0+ #0 [ 44.169365][ T10] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.179559][ T10] ================================================================== [ 44.187613][ T10] Kernel panic - not syncing: panic_on_warn set ... [ 44.194196][ T10] CPU: 1 PID: 10 Comm: rcu_preempt Not tainted 5.3.0+ #0 [ 44.201200][ T10] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.211239][ T10] Call Trace: [ 44.214524][ T10] dump_stack+0xf5/0x159 [ 44.218751][ T10] panic+0x209/0x639 [ 44.222627][ T10] ? vprintk_func+0x8d/0x140 [ 44.227204][ T10] kcsan_report.cold+0xc/0x1b [ 44.231857][ T10] __kcsan_setup_watchpoint+0x3ee/0x510 [ 44.237379][ T10] __tsan_read8+0x2c/0x30 [ 44.241706][ T10] rcu_gp_fqs_check_wake+0x93/0xd0 [ 44.246804][ T10] rcu_gp_fqs_loop+0x36c/0x580 [ 44.251586][ T10] rcu_gp_kthread+0x143/0x220 [ 44.256255][ T10] kthread+0x1d4/0x200 [ 44.260323][ T10] ? rcu_gp_cleanup+0x520/0x520 [ 44.265167][ T10] ? kthread_bind+0x50/0x50 [ 44.269666][ T10] ret_from_fork+0x1f/0x30 [ 44.275555][ T10] Kernel Offset: disabled [ 44.279889][ T10] Rebooting in 86400 seconds..