[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.188448][ T26] audit: type=1800 audit(1572090307.808:25): pid=7032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.215325][ T26] audit: type=1800 audit(1572090307.808:26): pid=7032 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.249438][ T26] audit: type=1800 audit(1572090307.808:27): pid=7032 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 '10.128.10.45' (ECDSA) to the list of known hosts. 2019/10/26 11:45:17 fuzzer started 2019/10/26 11:45:19 dialing manager at 10.128.0.105:33655 2019/10/26 11:45:19 syscalls: 2533 2019/10/26 11:45:19 code coverage: enabled 2019/10/26 11:45:19 comparison tracing: enabled 2019/10/26 11:45:19 extra coverage: extra coverage is not supported by the kernel 2019/10/26 11:45:19 setuid sandbox: enabled 2019/10/26 11:45:19 namespace sandbox: enabled 2019/10/26 11:45:19 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/26 11:45:19 fault injection: enabled 2019/10/26 11:45:19 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/26 11:45:19 net packet injection: enabled 2019/10/26 11:45:19 net device setup: enabled 2019/10/26 11:45:19 concurrency sanitizer: enabled 2019/10/26 11:45:21 adding functions to KCSAN blacklist: '__hrtimer_run_queues' 'tomoyo_supervisor' 'pipe_poll' 'tcp_add_backlog' 'rcu_gp_fqs_check_wake' 'ktime_get_real_seconds' 'find_next_bit' 'pid_update_inode' 'tcp_poll' 'find_get_pages_range_tag' '__ext4_new_inode' syzkaller login: [ 49.701055][ C0] ================================================================== [ 49.709305][ C0] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 49.717769][ C0] [ 49.720076][ C0] write to 0xffff888124922a08 of 4 bytes by task 7190 on cpu 1: [ 49.727679][ C0] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.732761][ C0] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.738283][ C0] nf_conntrack_in+0x410/0xa80 [ 49.743065][ C0] ipv4_conntrack_local+0xbe/0x130 [ 49.748189][ C0] nf_hook_slow+0x83/0x160 [ 49.752596][ C0] __ip_local_out+0x1f7/0x2b0 [ 49.757248][ C0] ip_local_out+0x31/0x90 [ 49.761560][ C0] __ip_queue_xmit+0x3a8/0xa40 [ 49.766310][ C0] ip_queue_xmit+0x45/0x60 [ 49.770702][ C0] __tcp_transmit_skb+0xe81/0x1d60 [ 49.775784][ C0] __tcp_send_ack+0x246/0x300 [ 49.780437][ C0] tcp_send_ack+0x34/0x40 [ 49.784741][ C0] tcp_cleanup_rbuf+0x130/0x360 [ 49.789579][ C0] tcp_recvmsg+0x633/0x1a30 [ 49.794053][ C0] [ 49.796358][ C0] read to 0xffff888124922a08 of 4 bytes by interrupt on cpu 0: [ 49.804830][ C0] __nf_conntrack_find_get+0x284/0x880 [ 49.810314][ C0] nf_conntrack_in+0x2ef/0xa80 [ 49.815052][ C0] ipv4_conntrack_in+0x27/0x40 [ 49.819790][ C0] nf_hook_slow+0x83/0x160 [ 49.824180][ C0] ip_rcv+0x12f/0x1a0 [ 49.828135][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.833826][ C0] __netif_receive_skb+0x37/0xf0 [ 49.838738][ C0] netif_receive_skb_internal+0x59/0x190 [ 49.844344][ C0] napi_gro_receive+0x28f/0x330 [ 49.849170][ C0] receive_buf+0x284/0x30b0 [ 49.853643][ C0] virtnet_poll+0x436/0x7d0 [ 49.858121][ C0] net_rx_action+0x3ae/0xa90 [ 49.862688][ C0] __do_softirq+0x115/0x33f [ 49.867158][ C0] [ 49.869457][ C0] Reported by Kernel Concurrency Sanitizer on: [ 49.875587][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 49.882870][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.892928][ C0] ================================================================== [ 49.900960][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 49.907522][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 49.914776][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.924803][ C0] Call Trace: [ 49.928072][ C0] dump_stack+0xf5/0x159 [ 49.932294][ C0] panic+0x210/0x640 [ 49.936174][ C0] ? napi_gro_receive+0x28f/0x330 [ 49.941175][ C0] ? vprintk_func+0x8d/0x140 [ 49.945739][ C0] kcsan_report.cold+0xc/0x10 [ 49.950390][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.955917][ C0] __tsan_read4+0x2c/0x30 [ 49.960223][ C0] __nf_conntrack_find_get+0x284/0x880 [ 49.965653][ C0] ? __tsan_write2+0x32/0x40 [ 49.970224][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.975836][ C0] nf_conntrack_in+0x2ef/0xa80 [ 49.980581][ C0] ipv4_conntrack_in+0x27/0x40 [ 49.985332][ C0] nf_hook_slow+0x83/0x160 [ 49.989722][ C0] ? nf_ct_bridge_unregister+0x70/0x70 [ 49.995164][ C0] ip_rcv+0x12f/0x1a0 [ 49.999130][ C0] ? ip_sublist_rcv+0x5e0/0x5e0 [ 50.003953][ C0] ? ip_local_deliver+0x210/0x210 [ 50.008952][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 50.014648][ C0] __netif_receive_skb+0x37/0xf0 [ 50.019561][ C0] netif_receive_skb_internal+0x59/0x190 [ 50.025169][ C0] napi_gro_receive+0x28f/0x330 [ 50.029994][ C0] receive_buf+0x284/0x30b0 [ 50.034471][ C0] ? __tsan_write8+0x32/0x40 [ 50.039042][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 50.044474][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 50.050080][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 50.055685][ C0] virtnet_poll+0x436/0x7d0 [ 50.060178][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 50.066396][ C0] net_rx_action+0x3ae/0xa90 [ 50.070967][ C0] __do_softirq+0x115/0x33f [ 50.075448][ C0] ? takeover_tasklets+0x250/0x250 [ 50.080543][ C0] run_ksoftirqd+0x46/0x60 [ 50.084935][ C0] smpboot_thread_fn+0x37d/0x4a0 [ 50.089848][ C0] kthread+0x1d4/0x200 [ 50.093890][ C0] ? constant_test_bit.constprop.0+0x30/0x30 [ 50.099843][ C0] ? kthread_stop+0x2d0/0x2d0 [ 50.104490][ C0] ret_from_fork+0x1f/0x30 [ 50.110132][ C0] Kernel Offset: disabled [ 50.114443][ C0] Rebooting in 86400 seconds..