[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.556858][ T23] audit: type=1800 audit(1570955359.944:25): pid=7064 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.599991][ T23] audit: type=1800 audit(1570955359.944:26): pid=7064 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.624428][ T23] audit: type=1800 audit(1570955359.944:27): pid=7064 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 '10.128.0.128' (ECDSA) to the list of known hosts. 2019/10/13 08:29:30 fuzzer started 2019/10/13 08:29:31 dialing manager at 10.128.0.105:43913 2019/10/13 08:29:31 syscalls: 2523 2019/10/13 08:29:31 code coverage: enabled 2019/10/13 08:29:31 comparison tracing: enabled 2019/10/13 08:29:31 extra coverage: extra coverage is not supported by the kernel 2019/10/13 08:29:31 setuid sandbox: enabled 2019/10/13 08:29:31 namespace sandbox: enabled 2019/10/13 08:29:31 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/13 08:29:31 fault injection: enabled 2019/10/13 08:29:31 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/13 08:29:31 net packet injection: enabled 2019/10/13 08:29:31 net device setup: enabled 2019/10/13 08:29:31 concurrency sanitizer: enabled syzkaller login: [ 47.043462][ C0] ================================================================== [ 47.051605][ C0] BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer [ 47.059642][ C0] [ 47.061948][ C0] write to 0xffffffff85caf310 of 4 bytes by interrupt on cpu 1: [ 47.069553][ C0] tick_sched_do_timer+0xc0/0xe0 [ 47.074528][ C0] tick_sched_timer+0x43/0xe0 [ 47.079224][ C0] __hrtimer_run_queues+0x288/0x600 [ 47.084400][ C0] hrtimer_interrupt+0x22a/0x480 [ 47.089318][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 47.094750][ C0] apic_timer_interrupt+0xf/0x20 [ 47.099665][ C0] __sanitizer_cov_trace_pc+0x26/0x50 [ 47.105013][ C0] tcp_options_write+0x11e/0x5e0 [ 47.109928][ C0] __tcp_transmit_skb+0x594/0x1cd0 [ 47.115012][ C0] __tcp_send_ack+0x246/0x300 [ 47.119667][ C0] tcp_send_ack+0x34/0x40 [ 47.123971][ C0] tcp_cleanup_rbuf+0x130/0x360 [ 47.128797][ C0] tcp_recvmsg+0x633/0x1a30 [ 47.133274][ C0] inet_recvmsg+0xbb/0x250 [ 47.137665][ C0] [ 47.139969][ C0] read to 0xffffffff85caf310 of 4 bytes by interrupt on cpu 0: [ 47.147487][ C0] tick_sched_do_timer+0x33/0xe0 [ 47.152398][ C0] tick_sched_timer+0x43/0xe0 [ 47.157053][ C0] __hrtimer_run_queues+0x288/0x600 [ 47.162227][ C0] hrtimer_interrupt+0x22a/0x480 [ 47.167141][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 47.172572][ C0] apic_timer_interrupt+0xf/0x20 [ 47.177488][ C0] __kcsan_check_watchpoint+0xed/0x180 [ 47.182922][ C0] __tsan_write4+0x18/0x40 [ 47.187314][ C0] __rcu_read_unlock+0x56/0xe0 [ 47.192068][ C0] nf_ct_deliver_cached_events+0xb5/0x2a0 [ 47.197762][ C0] nf_confirm+0x27d/0x2b0 [ 47.202081][ C0] ipv4_confirm+0xcf/0x160 [ 47.206474][ C0] nf_hook_slow+0x83/0x160 [ 47.210856][ C0] [ 47.213158][ C0] Reported by Kernel Concurrency Sanitizer on: [ 47.219296][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.3.0+ #0 [ 47.226198][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.236226][ C0] ================================================================== [ 47.244275][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 47.250835][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.3.0+ #0 [ 47.257740][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.267781][ C0] Call Trace: [ 47.271038][ C0] [ 47.273871][ C0] dump_stack+0xf5/0x159 [ 47.278093][ C0] panic+0x209/0x639 [ 47.281982][ C0] ? __rcu_read_unlock+0x56/0xe0 [ 47.286908][ C0] ? vprintk_func+0x8d/0x140 [ 47.291474][ C0] kcsan_report.cold+0xc/0x1b [ 47.296131][ C0] __kcsan_setup_watchpoint+0x3ee/0x510 [ 47.301654][ C0] __tsan_read4+0x2c/0x30 [ 47.305964][ C0] tick_sched_do_timer+0x33/0xe0 [ 47.310878][ C0] tick_sched_timer+0x43/0xe0 [ 47.315534][ C0] __hrtimer_run_queues+0x288/0x600 [ 47.320711][ C0] ? tick_sched_do_timer+0xe0/0xe0 [ 47.325801][ C0] hrtimer_interrupt+0x22a/0x480 [ 47.330717][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 47.336151][ C0] apic_timer_interrupt+0xf/0x20 [ 47.341073][ C0] [ 47.343996][ C0] RIP: 0010:__kcsan_check_watchpoint+0xed/0x180 [ 47.350219][ C0] Code: c3 49 89 c7 48 c1 eb 31 49 21 cf 81 e3 ff 3f 00 00 48 85 c0 78 05 45 84 c0 74 0f 4d 39 cf 77 0a 49 8d 5c 1f ff 48 39 df 76 2f <83> fa 03 75 8a b8 01 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 65 [ 47.369811][ C0] RSP: 0018:ffffc90000cb37c0 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13 [ 47.378210][ C0] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000ffffffffffff [ 47.386157][ C0] RDX: 0000000000000002 RSI: 000000000000002b RDI: 000088812b36b478 [ 47.394105][ C0] RBP: ffffc90000cb37e8 R08: 0000000000000001 R09: 000088812b36b47b [ 47.402066][ C0] R10: 00000000aaaaaaab R11: ffffffff86042d80 R12: 0000000000000001 [ 47.410015][ C0] R13: ffff88812b36b478 R14: 0000000000000004 R15: 0000000000000000 [ 47.417974][ C0] __tsan_write4+0x18/0x40 [ 47.422367][ C0] __rcu_read_unlock+0x56/0xe0 [ 47.427108][ C0] nf_ct_deliver_cached_events+0xb5/0x2a0 [ 47.432807][ C0] nf_confirm+0x27d/0x2b0 [ 47.437117][ C0] ipv4_confirm+0xcf/0x160 [ 47.441513][ C0] nf_hook_slow+0x83/0x160 [ 47.445905][ C0] ? nf_confirm+0x2b0/0x2b0 [ 47.450399][ C0] ip_local_deliver+0x1e5/0x210 [ 47.455243][ C0] ? ip_protocol_deliver_rcu+0x470/0x470 [ 47.460870][ C0] ip_rcv_finish+0x121/0x160 [ 47.465442][ C0] ip_rcv+0x18f/0x1a0 [ 47.469403][ C0] ? ip_sublist_rcv+0x5e0/0x5e0 [ 47.474250][ C0] ? ip_local_deliver+0x210/0x210 [ 47.479249][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 47.484947][ C0] __netif_receive_skb+0x37/0xf0 [ 47.489882][ C0] netif_receive_skb_internal+0x59/0x190 [ 47.495519][ C0] napi_gro_receive+0x28f/0x330 [ 47.500350][ C0] receive_buf+0x284/0x30b0 [ 47.504832][ C0] ? __tsan_write8+0x32/0x40 [ 47.509404][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 47.514838][ C0] ? __kcsan_setup_watchpoint+0x96/0x510 [ 47.520461][ C0] ? __kcsan_setup_watchpoint+0x96/0x510 [ 47.526076][ C0] virtnet_poll+0x436/0x7d0 [ 47.530561][ C0] net_rx_action+0x3ae/0xa50 [ 47.535135][ C0] __do_softirq+0x115/0x33f [ 47.539633][ C0] ? takeover_tasklets+0x250/0x250 [ 47.544722][ C0] run_ksoftirqd+0x46/0x60 [ 47.549129][ C0] smpboot_thread_fn+0x37d/0x4a0 [ 47.554044][ C0] kthread+0x1d4/0x200 [ 47.558090][ C0] ? constant_test_bit.constprop.0+0x30/0x30 [ 47.564046][ C0] ? kthread_bind+0x50/0x50 [ 47.568528][ C0] ret_from_fork+0x1f/0x30 [ 47.574220][ C0] Kernel Offset: disabled [ 47.578560][ C0] Rebooting in 86400 seconds..