[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 35.846625][ T26] audit: type=1800 audit(1570192494.410:25): pid=7075 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[ 35.888121][ T26] audit: type=1800 audit(1570192494.420:26): pid=7075 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[ 35.911691][ T26] audit: type=1800 audit(1570192494.420:27): pid=7075 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[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
Warning: Permanently added '10.128.0.206' (ECDSA) to the list of known hosts.
2019/10/04 12:35:05 fuzzer started
2019/10/04 12:35:07 dialing manager at 10.128.0.105:38119
2019/10/04 12:35:07 syscalls: 2523
2019/10/04 12:35:07 code coverage: enabled
2019/10/04 12:35:07 comparison tracing: enabled
2019/10/04 12:35:07 extra coverage: extra coverage is not supported by the kernel
2019/10/04 12:35:07 setuid sandbox: enabled
2019/10/04 12:35:07 namespace sandbox: enabled
2019/10/04 12:35:07 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/04 12:35:07 fault injection: enabled
2019/10/04 12:35:07 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/04 12:35:07 net packet injection: enabled
2019/10/04 12:35:07 net device setup: enabled
2019/10/04 12:35:07 concurrency sanitizer: enabled
syzkaller login: [ 49.063041][ C0] ==================================================================
[ 49.071345][ C0] BUG: KCSAN: data-race in __tcp_select_window+0x6b/0x4d0 and tcp_add_backlog+0x4a0/0xcc0
[ 49.081215][ C0]
[ 49.083528][ C0] read to 0xffff888124c5b32c of 4 bytes by task 7241 on cpu 1:
[ 49.091154][ C0] __tcp_select_window+0x6b/0x4d0
[ 49.096425][ C0] __tcp_transmit_skb+0x679/0x1cd0
[ 49.101613][ C0] __tcp_send_ack+0x246/0x300
[ 49.106534][ C0] tcp_send_ack+0x34/0x40
[ 49.110842][ C0] tcp_cleanup_rbuf+0x130/0x360
[ 49.115672][ C0] tcp_recvmsg+0x633/0x1a30
[ 49.120159][ C0] inet_recvmsg+0xbb/0x250
[ 49.124556][ C0] sock_recvmsg+0x92/0xb0
[ 49.128864][ C0] sock_read_iter+0x15f/0x1e0
[ 49.133539][ C0] new_sync_read+0x389/0x4f0
[ 49.138197][ C0] __vfs_read+0xb1/0xc0
[ 49.142332][ C0] vfs_read+0x143/0x2c0
[ 49.146477][ C0] ksys_read+0xd5/0x1b0
[ 49.150615][ C0] __x64_sys_read+0x4c/0x60
[ 49.155177][ C0]
[ 49.157620][ C0] write to 0xffff888124c5b32c of 4 bytes by interrupt on cpu 0:
[ 49.165590][ C0] tcp_add_backlog+0x4a0/0xcc0
[ 49.170336][ C0] tcp_v4_rcv+0x1aba/0x1bf0
[ 49.174837][ C0] ip_protocol_deliver_rcu+0x51/0x470
[ 49.180913][ C0] ip_local_deliver_finish+0x110/0x140
[ 49.186583][ C0] ip_local_deliver+0x133/0x210
[ 49.192212][ C0] ip_rcv_finish+0x121/0x160
[ 49.197106][ C0] ip_rcv+0x18f/0x1a0
[ 49.201264][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 49.207328][ C0] __netif_receive_skb+0x37/0xf0
[ 49.212336][ C0] netif_receive_skb_internal+0x59/0x190
[ 49.218214][ C0] napi_gro_receive+0x28f/0x330
[ 49.223223][ C0] receive_buf+0x284/0x30b0
[ 49.227724][ C0] virtnet_poll+0x436/0x7d0
[ 49.235330][ C0]
[ 49.237640][ C0] Reported by Kernel Concurrency Sanitizer on:
[ 49.244568][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0+ #0
[ 49.251405][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 49.261557][ C0] ==================================================================
[ 49.270036][ C0] Kernel panic - not syncing: panic_on_warn set ...
[ 49.276703][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0+ #0
[ 49.283656][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 49.293781][ C0] Call Trace:
[ 49.297057][ C0]
[ 49.299909][ C0] dump_stack+0xf5/0x159
[ 49.304319][ C0] panic+0x209/0x639
[ 49.308294][ C0] ? vprintk_func+0x8d/0x140
[ 49.312887][ C0] kcsan_report.cold+0x57/0xeb
[ 49.317645][ C0] __kcsan_setup_watchpoint+0x342/0x500
[ 49.323187][ C0] __tsan_write4+0x32/0x40
[ 49.327684][ C0] tcp_add_backlog+0x4a0/0xcc0
[ 49.332626][ C0] ? __rcu_read_unlock+0x62/0xe0
[ 49.337644][ C0] tcp_v4_rcv+0x1aba/0x1bf0
[ 49.342220][ C0] ? __tsan_read8+0x2c/0x30
[ 49.346891][ C0] ip_protocol_deliver_rcu+0x51/0x470
[ 49.352270][ C0] ip_local_deliver_finish+0x110/0x140
[ 49.358191][ C0] ip_local_deliver+0x133/0x210
[ 49.363043][ C0] ? ip_protocol_deliver_rcu+0x470/0x470
[ 49.368857][ C0] ip_rcv_finish+0x121/0x160
[ 49.373440][ C0] ip_rcv+0x18f/0x1a0
[ 49.377565][ C0] ? ip_sublist_rcv+0x5e0/0x5e0
[ 49.382521][ C0] ? ip_local_deliver+0x210/0x210
[ 49.387644][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 49.393362][ C0] __netif_receive_skb+0x37/0xf0
[ 49.398625][ C0] netif_receive_skb_internal+0x59/0x190
[ 49.405729][ C0] napi_gro_receive+0x28f/0x330
[ 49.410750][ C0] receive_buf+0x284/0x30b0
[ 49.415940][ C0] ? __tsan_write8+0x32/0x40
[ 49.420526][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0
[ 49.426156][ C0] ? virtqueue_get_buf+0x31/0x40
[ 49.431092][ C0] virtnet_poll+0x436/0x7d0
[ 49.435942][ C0] net_rx_action+0x3ae/0xa50
[ 49.440710][ C0] __do_softirq+0x115/0x33f
[ 49.445239][ C0] irq_exit+0xbb/0xe0
[ 49.449373][ C0] do_IRQ+0xdf/0x150
[ 49.453266][ C0] common_interrupt+0xf/0xf
[ 49.457834][ C0]
[ 49.460759][ C0] RIP: 0010:native_safe_halt+0xe/0x10
[ 49.466118][ C0] Code: 90 90 90 90 90 90 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 8c d2 4e 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 7c d2 4e 00 fb f4 90 55 48 89 e5 41 55 41 54 53 e8 82 78 a7 fc e8 5d 4e b9 fd 0f
[ 49.485720][ C0] RSP: 0018:ffffffff85a03de0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffda
[ 49.494208][ C0] RAX: 0e5604189374e317 RBX: 0000000000000000 RCX: 0000000000000076
[ 49.502252][ C0] RDX: 00000000002191c0 RSI: 020c49ba5e353f7d RDI: ffffffff85a55a28
[ 49.510303][ C0] RBP: ffffffff85a03e18 R08: 0000000000000000 R09: 0000ffff85a55a2f
[ 49.518436][ C0] R10: 00000000aaaaaaab R11: ffffffff86042cc0 R12: ffffffff85a2b780
[ 49.526397][ C0] R13: ffffffff85a2b780 R14: 0000000000000000 R15: 0000000000000000
[ 49.534393][ C0] ? default_idle+0x50/0x230
[ 49.538988][ C0] arch_cpu_idle+0x1f/0x30
[ 49.543681][ C0] default_idle_call+0x1e/0x40
[ 49.548884][ C0] do_idle+0x1ea/0x2c0
[ 49.552965][ C0] cpu_startup_entry+0x1b/0x20
[ 49.557731][ C0] rest_init+0xec/0xf6
[ 49.561791][ C0] ? trace_event_define_fields_vector_free_moved+0xce/0xce
[ 49.569239][ C0] arch_call_rest_init+0x17/0x37
[ 49.574190][ C0] start_kernel+0x83e/0x864
[ 49.578996][ C0] x86_64_start_reservations+0x29/0x2b
[ 49.584647][ C0] x86_64_start_kernel+0x72/0x76
[ 49.589746][ C0] secondary_startup_64+0xa4/0xb0
[ 49.596345][ C0] Kernel Offset: disabled
[ 49.600847][ C0] Rebooting in 86400 seconds..