[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 40.637265][ T23] audit: type=1800 audit(1571770238.358:25): pid=7086 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[ 40.673932][ T23] audit: type=1800 audit(1571770238.358:26): pid=7086 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[ 40.699965][ T23] audit: type=1800 audit(1571770238.358:27): pid=7086 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 '10.128.0.55' (ECDSA) to the list of known hosts.
2019/10/22 18:50:50 fuzzer started
2019/10/22 18:50:51 dialing manager at 10.128.0.105:33369
2019/10/22 18:50:51 syscalls: 2524
2019/10/22 18:50:51 code coverage: enabled
2019/10/22 18:50:51 comparison tracing: enabled
2019/10/22 18:50:51 extra coverage: extra coverage is not supported by the kernel
2019/10/22 18:50:51 setuid sandbox: enabled
2019/10/22 18:50:51 namespace sandbox: enabled
2019/10/22 18:50:51 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/22 18:50:51 fault injection: enabled
2019/10/22 18:50:51 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/22 18:50:51 net packet injection: enabled
2019/10/22 18:50:51 net device setup: enabled
2019/10/22 18:50:51 concurrency sanitizer: enabled
syzkaller login: [ 54.257702][ C0] ==================================================================
[ 54.265833][ C0] BUG: KCSAN: data-race in __tcp_select_window / tcp_add_backlog
[ 54.273525][ C0]
[ 54.275841][ C0] read to 0xffff88811cda29ec of 4 bytes by task 7243 on cpu 1:
[ 54.283365][ C0] __tcp_select_window+0x6b/0x4d0
[ 54.288373][ C0] __tcp_transmit_skb+0x700/0x1d60
[ 54.293473][ C0] __tcp_send_ack+0x246/0x300
[ 54.298132][ C0] tcp_send_ack+0x34/0x40
[ 54.302442][ C0] tcp_cleanup_rbuf+0x130/0x360
[ 54.307276][ C0] tcp_recvmsg+0x633/0x1a30
[ 54.311760][ C0] inet_recvmsg+0xbb/0x250
[ 54.316158][ C0] sock_recvmsg+0x92/0xb0
[ 54.320480][ C0] sock_read_iter+0x15f/0x1e0
[ 54.325139][ C0] new_sync_read+0x389/0x4f0
[ 54.329720][ C0] __vfs_read+0xb1/0xc0
[ 54.333856][ C0] vfs_read+0x143/0x2c0
[ 54.337994][ C0] ksys_read+0xd5/0x1b0
[ 54.342129][ C0] __x64_sys_read+0x4c/0x60
[ 54.346610][ C0]
[ 54.348924][ C0] write to 0xffff88811cda29ec of 4 bytes by interrupt on cpu 0:
[ 54.356534][ C0] tcp_add_backlog+0x4a0/0xcc0
[ 54.361278][ C0] tcp_v4_rcv+0x1a60/0x1bb0
[ 54.365763][ C0] ip_protocol_deliver_rcu+0x4d/0x420
[ 54.371117][ C0] ip_local_deliver_finish+0x110/0x140
[ 54.376556][ C0] ip_local_deliver+0x133/0x210
[ 54.381404][ C0] ip_rcv_finish+0x121/0x160
[ 54.385983][ C0] ip_rcv+0x18f/0x1a0
[ 54.389955][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 54.395660][ C0] __netif_receive_skb+0x37/0xf0
[ 54.400584][ C0] netif_receive_skb_internal+0x59/0x190
[ 54.406201][ C0] napi_gro_receive+0x28f/0x330
[ 54.411032][ C0] receive_buf+0x284/0x30b0
[ 54.415520][ C0] virtnet_poll+0x436/0x7d0
[ 54.419995][ C0]
[ 54.422303][ C0] Reported by Kernel Concurrency Sanitizer on:
[ 54.428441][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[ 54.435535][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 54.445580][ C0] ==================================================================
[ 54.453625][ C0] Kernel panic - not syncing: panic_on_warn set ...
[ 54.460195][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[ 54.467293][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 54.477325][ C0] Call Trace:
[ 54.480587][ C0]
[ 54.483436][ C0] dump_stack+0xf5/0x159
[ 54.487663][ C0] panic+0x210/0x640
[ 54.491554][ C0] ? __netif_receive_skb+0x37/0xf0
[ 54.496654][ C0] ? vprintk_func+0x8d/0x140
[ 54.501231][ C0] kcsan_report.cold+0xc/0x10
[ 54.505891][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0
[ 54.511426][ C0] __tsan_write4+0x32/0x40
[ 54.515828][ C0] tcp_add_backlog+0x4a0/0xcc0
[ 54.520582][ C0] tcp_v4_rcv+0x1a60/0x1bb0
[ 54.525068][ C0] ? __tsan_read8+0x2c/0x30
[ 54.529561][ C0] ip_protocol_deliver_rcu+0x4d/0x420
[ 54.534920][ C0] ip_local_deliver_finish+0x110/0x140
[ 54.540363][ C0] ip_local_deliver+0x133/0x210
[ 54.545205][ C0] ? ip_protocol_deliver_rcu+0x420/0x420
[ 54.550823][ C0] ip_rcv_finish+0x121/0x160
[ 54.555394][ C0] ip_rcv+0x18f/0x1a0
[ 54.559363][ C0] ? ip_sublist_rcv+0x5e0/0x5e0
[ 54.564197][ C0] ? ip_local_deliver+0x210/0x210
[ 54.569208][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 54.574911][ C0] __netif_receive_skb+0x37/0xf0
[ 54.579846][ C0] netif_receive_skb_internal+0x59/0x190
[ 54.585462][ C0] napi_gro_receive+0x28f/0x330
[ 54.590296][ C0] receive_buf+0x284/0x30b0
[ 54.594782][ C0] ? __tsan_write8+0x32/0x40
[ 54.599365][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0
[ 54.604807][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 54.610430][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 54.616048][ C0] virtnet_poll+0x436/0x7d0
[ 54.620541][ C0] net_rx_action+0x3ae/0xa90
[ 54.625123][ C0] __do_softirq+0x115/0x33f
[ 54.629613][ C0] irq_exit+0xbb/0xe0
[ 54.633578][ C0] do_IRQ+0xa6/0x180
[ 54.637464][ C0] common_interrupt+0xf/0xf
[ 54.641946][ C0]
[ 54.644885][ C0] RIP: 0010:native_safe_halt+0xe/0x10
[ 54.650247][ C0] Code: 90 90 90 90 90 90 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d fc b2 4b 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d ec b2 4b 00 fb f4 90 55 48 89 e5 41 55 41 54 53 e8 72 12 a4 fc e8 6d 8e b8 fd 0f
[ 54.669959][ C0] RSP: 0018:ffffffff85a03de0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffda
[ 54.678356][ C0] RAX: 1eb851eb851ebcf7 RBX: ffffffff85a2b780 RCX: 00000000000000fe
[ 54.686310][ C0] RDX: 0000000000040740 RSI: 020c49ba5e353f7d RDI: ffffffff85a563b8
[ 54.694266][ C0] RBP: ffffffff85a03e18 R08: 0000000000000000 R09: 0000ffff85a563bf
[ 54.702217][ C0] R10: 00000000aaaaaaab R11: ffffffff86045cc8 R12: 0000000000000000
[ 54.710169][ C0] R13: ffffffff85a2b780 R14: 0000000000000000 R15: 0000000000000000
[ 54.718145][ C0] ? default_idle+0x50/0x230
[ 54.722722][ C0] arch_cpu_idle+0x1f/0x30
[ 54.727128][ C0] default_idle_call+0x1e/0x40
[ 54.731874][ C0] do_idle+0x1af/0x280
[ 54.735931][ C0] cpu_startup_entry+0x1b/0x20
[ 54.740679][ C0] rest_init+0xec/0xf6
[ 54.744745][ C0] ? trace_event_define_fields_vector_free_moved+0xce/0xce
[ 54.751925][ C0] arch_call_rest_init+0x17/0x37
[ 54.756844][ C0] start_kernel+0x838/0x85e
[ 54.761335][ C0] x86_64_start_reservations+0x29/0x2b
[ 54.766774][ C0] x86_64_start_kernel+0x72/0x76
[ 54.771698][ C0] secondary_startup_64+0xa4/0xb0
[ 54.777945][ C0] Kernel Offset: disabled
[ 54.782263][ C0] Rebooting in 86400 seconds..