[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 41.588791][ T25] audit: type=1800 audit(1572773383.096:25): pid=7117 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 41.625994][ T25] audit: type=1800 audit(1572773383.096:26): pid=7117 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 41.659689][ T25] audit: type=1800 audit(1572773383.096:27): pid=7117 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 '10.128.0.103' (ECDSA) to the list of known hosts. 2019/11/03 09:29:53 fuzzer started 2019/11/03 09:29:55 dialing manager at 10.128.0.105:43165 2019/11/03 09:29:55 syscalls: 2554 2019/11/03 09:29:55 code coverage: enabled 2019/11/03 09:29:55 comparison tracing: enabled 2019/11/03 09:29:55 extra coverage: extra coverage is not supported by the kernel 2019/11/03 09:29:55 setuid sandbox: enabled 2019/11/03 09:29:55 namespace sandbox: enabled 2019/11/03 09:29:55 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/03 09:29:55 fault injection: enabled 2019/11/03 09:29:55 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/03 09:29:55 net packet injection: enabled 2019/11/03 09:29:55 net device setup: enabled 2019/11/03 09:29:55 concurrency sanitizer: enabled 2019/11/03 09:29:58 adding functions to KCSAN blacklist: 'run_timer_softirq' 'tcp_poll' 'generic_permission' 'do_nanosleep' '__hrtimer_run_queues' '__tcp_select_window' 'tcp_add_backlog' 'tomoyo_supervisor' 'rcu_gp_fqs_loop' 'tick_sched_do_timer' 'task_dump_owner' syzkaller login: [ 58.414360][ T7269] ================================================================== [ 58.422631][ T7269] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 58.431107][ T7269] [ 58.433529][ T7269] read to 0xffff88811e930808 of 4 bytes by interrupt on cpu 1: [ 58.441659][ T7269] __nf_conntrack_find_get+0x284/0x880 [ 58.447116][ T7269] nf_conntrack_in+0x2ef/0xa80 [ 58.451861][ T7269] ipv4_conntrack_in+0x27/0x40 [ 58.456824][ T7269] nf_hook_slow+0x83/0x160 [ 58.461227][ T7269] ip_rcv+0x12f/0x1a0 [ 58.465198][ T7269] __netif_receive_skb_one_core+0xa7/0xe0 [ 58.470921][ T7269] __netif_receive_skb+0x37/0xf0 [ 58.475926][ T7269] netif_receive_skb_internal+0x59/0x190 [ 58.481638][ T7269] napi_gro_receive+0x28f/0x330 [ 58.486579][ T7269] receive_buf+0x284/0x30b0 [ 58.491106][ T7269] virtnet_poll+0x436/0x7d0 [ 58.495595][ T7269] net_rx_action+0x3ae/0xa90 [ 58.500197][ T7269] __do_softirq+0x115/0x33f [ 58.504704][ T7269] irq_exit+0xbb/0xe0 [ 58.508699][ T7269] [ 58.511031][ T7269] write to 0xffff88811e930808 of 4 bytes by task 7269 on cpu 0: [ 58.518653][ T7269] __nf_ct_refresh_acct+0xfb/0x1b0 [ 58.523770][ T7269] nf_conntrack_tcp_packet+0xd40/0x3390 [ 58.530163][ T7269] nf_conntrack_in+0x410/0xa80 [ 58.534915][ T7269] ipv4_conntrack_local+0xbe/0x130 [ 58.540027][ T7269] nf_hook_slow+0x83/0x160 [ 58.544421][ T7269] __ip_local_out+0x1f7/0x2b0 [ 58.549161][ T7269] ip_local_out+0x31/0x90 [ 58.553465][ T7269] __ip_queue_xmit+0x3a8/0xa40 [ 58.558227][ T7269] ip_queue_xmit+0x45/0x60 [ 58.562618][ T7269] __tcp_transmit_skb+0xe81/0x1d60 [ 58.567704][ T7269] __tcp_send_ack+0x246/0x300 [ 58.572363][ T7269] tcp_send_ack+0x34/0x40 [ 58.576681][ T7269] tcp_cleanup_rbuf+0x130/0x360 [ 58.581509][ T7269] [ 58.583823][ T7269] Reported by Kernel Concurrency Sanitizer on: [ 58.590488][ T7269] CPU: 0 PID: 7269 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 58.599521][ T7269] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.609674][ T7269] ================================================================== [ 58.617714][ T7269] Kernel panic - not syncing: panic_on_warn set ... [ 58.624294][ T7269] CPU: 0 PID: 7269 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 58.631729][ T7269] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.641856][ T7269] Call Trace: [ 58.645136][ T7269] dump_stack+0xf5/0x159 [ 58.649381][ T7269] panic+0x210/0x640 [ 58.653272][ T7269] ? ip_queue_xmit+0x45/0x60 [ 58.657921][ T7269] ? vprintk_func+0x8d/0x140 [ 58.662523][ T7269] kcsan_report.cold+0xc/0x10 [ 58.667325][ T7269] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 58.672903][ T7269] __tsan_write4+0x32/0x40 [ 58.677348][ T7269] __nf_ct_refresh_acct+0xfb/0x1b0 [ 58.682450][ T7269] nf_conntrack_tcp_packet+0xd40/0x3390 [ 58.688012][ T7269] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 58.693627][ T7269] nf_conntrack_in+0x410/0xa80 [ 58.698476][ T7269] ipv4_conntrack_local+0xbe/0x130 [ 58.703683][ T7269] nf_hook_slow+0x83/0x160 [ 58.708084][ T7269] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 58.712843][ T7269] __ip_local_out+0x1f7/0x2b0 [ 58.717515][ T7269] ? constant_test_bit+0x30/0x30 [ 58.722453][ T7269] ip_local_out+0x31/0x90 [ 58.726765][ T7269] __ip_queue_xmit+0x3a8/0xa40 [ 58.731522][ T7269] ip_queue_xmit+0x45/0x60 [ 58.736024][ T7269] __tcp_transmit_skb+0xe81/0x1d60 [ 58.741119][ T7269] __tcp_send_ack+0x246/0x300 [ 58.745780][ T7269] tcp_send_ack+0x34/0x40 [ 58.750088][ T7269] tcp_cleanup_rbuf+0x130/0x360 [ 58.754921][ T7269] tcp_recvmsg+0x633/0x1a30 [ 58.759429][ T7269] inet_recvmsg+0xbb/0x250 [ 58.763842][ T7269] ? __tsan_read8+0x2c/0x30 [ 58.768375][ T7269] ? inet_sendpage+0x100/0x100 [ 58.773273][ T7269] sock_recvmsg+0x92/0xb0 [ 58.777592][ T7269] sock_read_iter+0x15f/0x1e0 [ 58.782273][ T7269] new_sync_read+0x389/0x4f0 [ 58.786862][ T7269] __vfs_read+0xb1/0xc0 [ 58.791024][ T7269] vfs_read+0x143/0x2c0 [ 58.795188][ T7269] ksys_read+0xd5/0x1b0 [ 58.799356][ T7269] __x64_sys_read+0x4c/0x60 [ 58.803855][ T7269] do_syscall_64+0xcc/0x370 [ 58.808344][ T7269] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 58.814277][ T7269] RIP: 0033:0x47c530 [ 58.818177][ T7269] 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 [ 58.837784][ T7269] RSP: 002b:000000c4202ed7d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 58.846179][ T7269] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 58.854135][ T7269] RDX: 0000000000001000 RSI: 000000c4203f0000 RDI: 0000000000000003 [ 58.862083][ T7269] RBP: 000000c4202ed828 R08: 0000000000000000 R09: 0000000000000000 [ 58.870045][ T7269] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 58.877997][ T7269] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 58.887456][ T7269] Kernel Offset: disabled [ 58.891798][ T7269] Rebooting in 86400 seconds..