[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.533276][ T26] audit: type=1800 audit(1571703624.128:25): pid=6995 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.553101][ T26] audit: type=1800 audit(1571703624.128:26): pid=6995 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.574929][ T26] audit: type=1800 audit(1571703624.128:27): pid=6995 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 '10.128.10.5' (ECDSA) to the list of known hosts. 2019/10/22 00:20:35 fuzzer started 2019/10/22 00:20:36 dialing manager at 10.128.0.105:39747 2019/10/22 00:20:36 syscalls: 2524 2019/10/22 00:20:36 code coverage: enabled 2019/10/22 00:20:36 comparison tracing: enabled 2019/10/22 00:20:36 extra coverage: extra coverage is not supported by the kernel 2019/10/22 00:20:36 setuid sandbox: enabled 2019/10/22 00:20:36 namespace sandbox: enabled 2019/10/22 00:20:36 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 00:20:36 fault injection: enabled 2019/10/22 00:20:36 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 00:20:36 net packet injection: enabled 2019/10/22 00:20:36 net device setup: enabled 2019/10/22 00:20:36 concurrency sanitizer: enabled syzkaller login: [ 47.152253][ C1] ================================================================== [ 47.160399][ C1] BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer [ 47.168455][ C1] [ 47.170765][ C1] read to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 0: [ 47.178395][ C1] tick_sched_do_timer+0x33/0xe0 [ 47.183318][ C1] tick_sched_timer+0x43/0xe0 [ 47.187973][ C1] __hrtimer_run_queues+0x288/0x600 [ 47.193161][ C1] hrtimer_interrupt+0x22a/0x480 [ 47.198073][ C1] smp_apic_timer_interrupt+0xdc/0x280 [ 47.203510][ C1] apic_timer_interrupt+0xf/0x20 [ 47.208435][ C1] __kcsan_check_watchpoint+0xb2/0x180 [ 47.213876][ C1] __tsan_read4+0x15/0x30 [ 47.218190][ C1] virtqueue_get_buf_ctx+0x438/0x5c0 [ 47.223454][ C1] receive_buf+0x183e/0x30b0 [ 47.228018][ C1] virtnet_poll+0x436/0x7d0 [ 47.232508][ C1] net_rx_action+0x3ae/0xa90 [ 47.237083][ C1] __do_softirq+0x115/0x33f [ 47.241562][ C1] run_ksoftirqd+0x46/0x60 [ 47.245948][ C1] [ 47.248259][ C1] write to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 1: [ 47.255874][ C1] tick_sched_do_timer+0xc0/0xe0 [ 47.261525][ C1] tick_sched_timer+0x43/0xe0 [ 47.266194][ C1] __hrtimer_run_queues+0x288/0x600 [ 47.271368][ C1] hrtimer_interrupt+0x22a/0x480 [ 47.276380][ C1] smp_apic_timer_interrupt+0xdc/0x280 [ 47.281812][ C1] apic_timer_interrupt+0xf/0x20 [ 47.286728][ C1] [ 47.289030][ C1] Reported by Kernel Concurrency Sanitizer on: [ 47.295159][ C1] CPU: 1 PID: 7157 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 47.302595][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.312638][ C1] ================================================================== [ 47.320672][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 47.327236][ C1] CPU: 1 PID: 7157 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 47.334754][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.344781][ C1] Call Trace: [ 47.348039][ C1] [ 47.350876][ C1] dump_stack+0xf5/0x159 [ 47.355108][ C1] panic+0x210/0x640 [ 47.358980][ C1] ? vprintk_func+0x8d/0x140 [ 47.363561][ C1] kcsan_report.cold+0xc/0x10 [ 47.368220][ C1] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 47.373748][ C1] __tsan_write4+0x32/0x40 [ 47.378152][ C1] tick_sched_do_timer+0xc0/0xe0 [ 47.383092][ C1] tick_sched_timer+0x43/0xe0 [ 47.387749][ C1] __hrtimer_run_queues+0x288/0x600 [ 47.392924][ C1] ? tick_sched_do_timer+0xe0/0xe0 [ 47.398023][ C1] hrtimer_interrupt+0x22a/0x480 [ 47.402945][ C1] smp_apic_timer_interrupt+0xdc/0x280 [ 47.408383][ C1] ? smp_reschedule_interrupt+0x71/0x1d0 [ 47.414004][ C1] apic_timer_interrupt+0xf/0x20 [ 47.418929][ C1] [ 47.421888][ C1] RIP: 0033:0x6099c3 [ 47.425764][ C1] Code: a3 d9 e4 ff e9 0e ff ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 0f 86 b4 01 00 00 <48> 83 ec 38 48 89 6c 24 30 48 8d 6c 24 30 48 8b 44 24 48 48 8b 10 [ 47.445355][ C1] RSP: 002b:000000c4204f1ab0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 [ 47.453753][ C1] RAX: 000000c4204b4028 RBX: 0000000000008000 RCX: 000000c42006f080 [ 47.461712][ C1] RDX: 0000000000000000 RSI: 0000000000001d44 RDI: 000000c4204c02b8 [ 47.469672][ C1] RBP: 000000c4204f1b50 R08: 000000c4204ba000 R09: 00000000000062bc [ 47.477631][ C1] R10: 00000000ffffffff R11: 00000000000061eb R12: 0000000000000010 [ 47.485581][ C1] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 47.495066][ C1] Kernel Offset: disabled [ 47.499400][ C1] Rebooting in 86400 seconds..