[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 34.606466][ T26] audit: type=1800 audit(1571785072.861:25): pid=7068 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[ 34.626326][ T26] audit: type=1800 audit(1571785072.861:26): pid=7068 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[ 34.647028][ T26] audit: type=1800 audit(1571785072.861:27): pid=7068 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 '10.128.1.7' (ECDSA) to the list of known hosts.
2019/10/22 22:58:01 fuzzer started
2019/10/22 22:58:02 dialing manager at 10.128.0.105:33369
2019/10/22 22:58:02 syscalls: 2524
2019/10/22 22:58:02 code coverage: enabled
2019/10/22 22:58:02 comparison tracing: enabled
2019/10/22 22:58:02 extra coverage: extra coverage is not supported by the kernel
2019/10/22 22:58:02 setuid sandbox: enabled
2019/10/22 22:58:02 namespace sandbox: enabled
2019/10/22 22:58:02 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/22 22:58:02 fault injection: enabled
2019/10/22 22:58:02 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/22 22:58:02 net packet injection: enabled
2019/10/22 22:58:02 net device setup: enabled
2019/10/22 22:58:02 concurrency sanitizer: enabled
syzkaller login: [ 44.340750][ C0] ==================================================================
[ 44.348872][ C0] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg
[ 44.355898][ C0]
[ 44.358218][ C0] read to 0xffff8881222669f8 of 8 bytes by task 7219 on cpu 1:
[ 44.365744][ C0] tcp_recvmsg+0x470/0x1a30
[ 44.370228][ C0] inet_recvmsg+0xbb/0x250
[ 44.374629][ C0] sock_recvmsg+0x92/0xb0
[ 44.378940][ C0] sock_read_iter+0x15f/0x1e0
[ 44.384033][ C0] new_sync_read+0x389/0x4f0
[ 44.388606][ C0] __vfs_read+0xb1/0xc0
[ 44.392742][ C0] vfs_read+0x143/0x2c0
[ 44.396883][ C0] ksys_read+0xd5/0x1b0
[ 44.401019][ C0] __x64_sys_read+0x4c/0x60
[ 44.405510][ C0] do_syscall_64+0xcc/0x370
[ 44.410007][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 44.415886][ C0]
[ 44.418201][ C0] write to 0xffff8881222669f8 of 8 bytes by interrupt on cpu 0:
[ 44.425824][ C0] tcp_add_backlog+0x45a/0xcc0
[ 44.430575][ C0] tcp_v4_rcv+0x1a60/0x1bb0
[ 44.435059][ C0] ip_protocol_deliver_rcu+0x4d/0x420
[ 44.440412][ C0] ip_local_deliver_finish+0x110/0x140
[ 44.445856][ C0] ip_local_deliver+0x133/0x210
[ 44.450689][ C0] ip_rcv_finish+0x121/0x160
[ 44.455274][ C0] ip_rcv+0x18f/0x1a0
[ 44.459239][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 44.464953][ C0] __netif_receive_skb+0x37/0xf0
[ 44.469874][ C0] netif_receive_skb_internal+0x59/0x190
[ 44.475494][ C0] napi_gro_receive+0x28f/0x330
[ 44.480434][ C0] receive_buf+0x284/0x30b0
[ 44.484930][ C0] virtnet_poll+0x436/0x7d0
[ 44.489408][ C0]
[ 44.491714][ C0] Reported by Kernel Concurrency Sanitizer on:
[ 44.497873][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[ 44.504969][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 44.515006][ C0] ==================================================================
[ 44.523058][ C0] Kernel panic - not syncing: panic_on_warn set ...
[ 44.529640][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
[ 44.536735][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 44.546793][ C0] Call Trace:
[ 44.550057][ C0]
[ 44.552904][ C0] dump_stack+0xf5/0x159
[ 44.557132][ C0] panic+0x210/0x640
[ 44.561012][ C0] ? __netif_receive_skb+0x37/0xf0
[ 44.566107][ C0] ? vprintk_func+0x8d/0x140
[ 44.570687][ C0] kcsan_report.cold+0xc/0x10
[ 44.575372][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0
[ 44.580913][ C0] ? __sanitizer_cov_trace_cmp4+0x16/0x20
[ 44.586618][ C0] __tsan_write8+0x32/0x40
[ 44.591024][ C0] tcp_add_backlog+0x45a/0xcc0
[ 44.597177][ C0] tcp_v4_rcv+0x1a60/0x1bb0
[ 44.601666][ C0] ? __tsan_read8+0x2c/0x30
[ 44.606165][ C0] ip_protocol_deliver_rcu+0x4d/0x420
[ 44.611534][ C0] ip_local_deliver_finish+0x110/0x140
[ 44.616978][ C0] ip_local_deliver+0x133/0x210
[ 44.621813][ C0] ? ip_protocol_deliver_rcu+0x420/0x420
[ 44.627447][ C0] ip_rcv_finish+0x121/0x160
[ 44.632039][ C0] ip_rcv+0x18f/0x1a0
[ 44.636009][ C0] ? ip_sublist_rcv+0x5e0/0x5e0
[ 44.640846][ C0] ? ip_local_deliver+0x210/0x210
[ 44.645857][ C0] __netif_receive_skb_one_core+0xa7/0xe0
[ 44.651739][ C0] __netif_receive_skb+0x37/0xf0
[ 44.656664][ C0] netif_receive_skb_internal+0x59/0x190
[ 44.662285][ C0] napi_gro_receive+0x28f/0x330
[ 44.667143][ C0] receive_buf+0x284/0x30b0
[ 44.671632][ C0] ? __tsan_write8+0x32/0x40
[ 44.676211][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0
[ 44.681650][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 44.687277][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 44.692893][ C0] virtnet_poll+0x436/0x7d0
[ 44.697401][ C0] net_rx_action+0x3ae/0xa90
[ 44.701997][ C0] __do_softirq+0x115/0x33f
[ 44.706493][ C0] irq_exit+0xbb/0xe0
[ 44.710462][ C0] do_IRQ+0xa6/0x180
[ 44.714341][ C0] common_interrupt+0xf/0xf
[ 44.718822][ C0]
[ 44.721774][ C0] RIP: 0010:native_safe_halt+0xe/0x10
[ 44.727137][ 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
[ 44.746722][ C0] RSP: 0018:ffffffff85a03de0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffda
[ 44.755129][ C0] RAX: 5810624dd2f1b077 RBX: ffffffff85a2b780 RCX: 00000000000002bc
[ 44.763109][ C0] RDX: 0000000000059d80 RSI: 020c49ba5e353f7d RDI: ffffffff85a563b8
[ 44.771068][ C0] RBP: ffffffff85a03e18 R08: 0000000000000000 R09: 0000ffff85a563bf
[ 44.779038][ C0] R10: 00000000aaaaaaab R11: ffffffff86045cc8 R12: 0000000000000000
[ 44.786995][ C0] R13: ffffffff85a2b780 R14: 0000000000000000 R15: 0000000000000000
[ 44.794977][ C0] ? default_idle+0x50/0x230
[ 44.799561][ C0] arch_cpu_idle+0x1f/0x30
[ 44.803962][ C0] default_idle_call+0x1e/0x40
[ 44.808707][ C0] do_idle+0x1af/0x280
[ 44.812763][ C0] cpu_startup_entry+0x1b/0x20
[ 44.817510][ C0] rest_init+0xec/0xf6
[ 44.821566][ C0] ? trace_event_define_fields_vector_free_moved+0xce/0xce
[ 44.828749][ C0] arch_call_rest_init+0x17/0x37
[ 44.833669][ C0] start_kernel+0x838/0x85e
[ 44.838159][ C0] x86_64_start_reservations+0x29/0x2b
[ 44.843600][ C0] x86_64_start_kernel+0x72/0x76
[ 44.848534][ C0] secondary_startup_64+0xa4/0xb0
[ 44.854795][ C0] Kernel Offset: disabled
[ 44.859114][ C0] Rebooting in 86400 seconds..