[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.397313][ T25] audit: type=1800 audit(1570192263.441:25): pid=7004 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 39.416979][ T25] audit: type=1800 audit(1570192263.441:26): pid=7004 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 39.485175][ T25] audit: type=1800 audit(1570192263.531:27): pid=7004 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 '10.128.0.194' (ECDSA) to the list of known hosts. 2019/10/04 12:31:13 fuzzer started 2019/10/04 12:31:15 dialing manager at 10.128.0.105:38119 2019/10/04 12:31:15 syscalls: 2523 2019/10/04 12:31:15 code coverage: enabled 2019/10/04 12:31:15 comparison tracing: enabled 2019/10/04 12:31:15 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:31:15 setuid sandbox: enabled 2019/10/04 12:31:15 namespace sandbox: enabled 2019/10/04 12:31:15 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:31:15 fault injection: enabled 2019/10/04 12:31:15 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:31:15 net packet injection: enabled 2019/10/04 12:31:15 net device setup: enabled 2019/10/04 12:31:15 concurrency sanitizer: enabled syzkaller login: [ 51.506477][ T7170] ================================================================== [ 51.514671][ T7170] BUG: KCSAN: data-race in __nf_conntrack_find_get+0x284/0x870 and __nf_ct_refresh_acct+0xfb/0x1b0 [ 51.525360][ T7170] [ 51.527674][ T7170] read to 0xffff888122f25e08 of 4 bytes by interrupt on cpu 0: [ 51.535217][ T7170] __nf_conntrack_find_get+0x284/0x870 [ 51.540649][ T7170] nf_conntrack_in+0x2ef/0xaa0 [ 51.545388][ T7170] ipv4_conntrack_in+0x27/0x40 [ 51.550128][ T7170] nf_hook_slow+0x83/0x160 [ 51.554540][ T7170] ip_rcv+0x12f/0x1a0 [ 51.558512][ T7170] __netif_receive_skb_one_core+0xa7/0xe0 [ 51.564243][ T7170] __netif_receive_skb+0x37/0xf0 [ 51.569163][ T7170] netif_receive_skb_internal+0x59/0x190 [ 51.574772][ T7170] napi_gro_receive+0x28f/0x330 [ 51.579610][ T7170] receive_buf+0x284/0x30b0 [ 51.584091][ T7170] virtnet_poll+0x436/0x7d0 [ 51.588569][ T7170] net_rx_action+0x3ae/0xa50 [ 51.593140][ T7170] __do_softirq+0x115/0x33f [ 51.597616][ T7170] irq_exit+0xbb/0xe0 [ 51.601565][ T7170] [ 51.603871][ T7170] write to 0xffff888122f25e08 of 4 bytes by task 7170 on cpu 1: [ 51.611477][ T7170] __nf_ct_refresh_acct+0xfb/0x1b0 [ 51.616594][ T7170] nf_conntrack_tcp_packet+0xd40/0x3390 [ 51.622126][ T7170] nf_conntrack_in+0x410/0xaa0 [ 51.626865][ T7170] ipv4_conntrack_local+0xbe/0x130 [ 51.631953][ T7170] nf_hook_slow+0x83/0x160 [ 51.636346][ T7170] __ip_local_out+0x1f7/0x2b0 [ 51.640996][ T7170] ip_local_out+0x31/0x90 [ 51.645301][ T7170] __ip_queue_xmit+0x3a8/0xa40 [ 51.650039][ T7170] ip_queue_xmit+0x45/0x60 [ 51.654467][ T7170] __tcp_transmit_skb+0xdeb/0x1cd0 [ 51.659553][ T7170] __tcp_send_ack+0x246/0x300 [ 51.664204][ T7170] tcp_send_ack+0x34/0x40 [ 51.668542][ T7170] tcp_cleanup_rbuf+0x130/0x360 [ 51.673361][ T7170] [ 51.675662][ T7170] Reported by Kernel Concurrency Sanitizer on: [ 51.681793][ T7170] CPU: 1 PID: 7170 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 51.688872][ T7170] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.698918][ T7170] ================================================================== [ 51.706954][ T7170] Kernel panic - not syncing: panic_on_warn set ... [ 51.713515][ T7170] CPU: 1 PID: 7170 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 51.720603][ T7170] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.730629][ T7170] Call Trace: [ 51.733909][ T7170] dump_stack+0xf5/0x159 [ 51.738135][ T7170] panic+0x209/0x639 [ 51.742012][ T7170] ? vprintk_func+0x8d/0x140 [ 51.746582][ T7170] kcsan_report.cold+0x57/0xeb [ 51.751324][ T7170] __kcsan_setup_watchpoint+0x342/0x500 [ 51.756858][ T7170] __tsan_write4+0x32/0x40 [ 51.761261][ T7170] __nf_ct_refresh_acct+0xfb/0x1b0 [ 51.766350][ T7170] nf_conntrack_tcp_packet+0xd40/0x3390 [ 51.771882][ T7170] nf_conntrack_in+0x410/0xaa0 [ 51.776625][ T7170] ipv4_conntrack_local+0xbe/0x130 [ 51.781714][ T7170] nf_hook_slow+0x83/0x160 [ 51.786106][ T7170] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 51.790848][ T7170] __ip_local_out+0x1f7/0x2b0 [ 51.795505][ T7170] ? constant_test_bit+0x30/0x30 [ 51.800421][ T7170] ip_local_out+0x31/0x90 [ 51.804728][ T7170] __ip_queue_xmit+0x3a8/0xa40 [ 51.809479][ T7170] ip_queue_xmit+0x45/0x60 [ 51.813881][ T7170] __tcp_transmit_skb+0xdeb/0x1cd0 [ 51.818976][ T7170] __tcp_send_ack+0x246/0x300 [ 51.823632][ T7170] tcp_send_ack+0x34/0x40 [ 51.827935][ T7170] tcp_cleanup_rbuf+0x130/0x360 [ 51.832764][ T7170] tcp_recvmsg+0x633/0x1a30 [ 51.837263][ T7170] inet_recvmsg+0xbb/0x250 [ 51.841656][ T7170] ? __tsan_read8+0x2c/0x30 [ 51.846145][ T7170] ? inet_sendpage+0x100/0x100 [ 51.850884][ T7170] sock_recvmsg+0x92/0xb0 [ 51.855190][ T7170] sock_read_iter+0x15f/0x1e0 [ 51.859847][ T7170] new_sync_read+0x389/0x4f0 [ 51.864417][ T7170] __vfs_read+0xb1/0xc0 [ 51.868552][ T7170] vfs_read+0x143/0x2c0 [ 51.872685][ T7170] ksys_read+0xd5/0x1b0 [ 51.876820][ T7170] __x64_sys_read+0x4c/0x60 [ 51.881303][ T7170] do_syscall_64+0xcf/0x2f0 [ 51.885788][ T7170] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 51.891655][ T7170] RIP: 0033:0x47c530 [ 51.895552][ T7170] 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 [ 51.915151][ T7170] RSP: 002b:000000c4202d67d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 51.923537][ T7170] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 51.931485][ T7170] RDX: 0000000000001000 RSI: 000000c4200a0000 RDI: 0000000000000003 [ 51.939433][ T7170] RBP: 000000c4202d6830 R08: 0000000000000000 R09: 0000000000000000 [ 51.947378][ T7170] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000100 [ 51.955324][ T7170] R13: ffffffffffffffff R14: 0000000000000020 R15: ffffffffffffffff [ 51.964635][ T7170] Kernel Offset: disabled [ 51.968957][ T7170] Rebooting in 86400 seconds..