[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 34.059478][ T26] audit: type=1800 audit(1571775094.135:25): pid=6981 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[ 34.086827][ T26] audit: type=1800 audit(1571775094.135:26): pid=6981 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[ 34.124745][ T26] audit: type=1800 audit(1571775094.135:27): pid=6981 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 '10.128.0.193' (ECDSA) to the list of known hosts.
2019/10/22 20:11:42 fuzzer started
2019/10/22 20:11:44 dialing manager at 10.128.0.105:33369
2019/10/22 20:11:44 syscalls: 2524
2019/10/22 20:11:44 code coverage: enabled
2019/10/22 20:11:44 comparison tracing: enabled
2019/10/22 20:11:44 extra coverage: extra coverage is not supported by the kernel
2019/10/22 20:11:44 setuid sandbox: enabled
2019/10/22 20:11:44 namespace sandbox: enabled
2019/10/22 20:11:44 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/22 20:11:44 fault injection: enabled
2019/10/22 20:11:44 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/22 20:11:44 net packet injection: enabled
2019/10/22 20:11:44 net device setup: enabled
2019/10/22 20:11:44 concurrency sanitizer: enabled
syzkaller login: [ 44.845168][ C1] ==================================================================
[ 44.853285][ C1] BUG: KCSAN: data-race in __tcp_select_window / tcp_add_backlog
[ 44.860976][ C1]
[ 44.863290][ C1] read to 0xffff88812203ca2c of 4 bytes by task 7131 on cpu 0:
[ 44.870824][ C1] __tcp_select_window+0x6b/0x4d0
[ 44.875831][ C1] __tcp_transmit_skb+0x700/0x1d60
[ 44.880923][ C1] __tcp_send_ack+0x246/0x300
[ 44.885584][ C1] tcp_send_ack+0x34/0x40
[ 44.889898][ C1] tcp_cleanup_rbuf+0x130/0x360
[ 44.894746][ C1] tcp_recvmsg+0x633/0x1a30
[ 44.899232][ C1] inet_recvmsg+0xbb/0x250
[ 44.903630][ C1] sock_recvmsg+0x92/0xb0
[ 44.907944][ C1] sock_read_iter+0x15f/0x1e0
[ 44.912607][ C1] new_sync_read+0x389/0x4f0
[ 44.917178][ C1] __vfs_read+0xb1/0xc0
[ 44.921317][ C1] vfs_read+0x143/0x2c0
[ 44.925457][ C1] ksys_read+0xd5/0x1b0
[ 44.929597][ C1] __x64_sys_read+0x4c/0x60
[ 44.934075][ C1]
[ 44.936391][ C1] write to 0xffff88812203ca2c of 4 bytes by interrupt on cpu 1:
[ 44.944018][ C1] tcp_add_backlog+0x4a0/0xcc0
[ 44.948765][ C1] tcp_v4_rcv+0x1a60/0x1bb0
[ 44.953248][ C1] ip_protocol_deliver_rcu+0x4d/0x420
[ 44.958630][ C1] ip_local_deliver_finish+0x110/0x140
[ 44.964069][ C1] ip_local_deliver+0x133/0x210
[ 44.968902][ C1] ip_rcv_finish+0x121/0x160
[ 44.973472][ C1] ip_rcv+0x18f/0x1a0
[ 44.977437][ C1] __netif_receive_skb_one_core+0xa7/0xe0
[ 44.983134][ C1] __netif_receive_skb+0x37/0xf0
[ 44.988054][ C1] netif_receive_skb_internal+0x59/0x190
[ 44.993672][ C1] napi_gro_receive+0x28f/0x330
[ 44.998504][ C1] receive_buf+0x284/0x30b0
[ 45.002985][ C1] virtnet_poll+0x436/0x7d0
[ 45.007463][ C1]
[ 45.009768][ C1] Reported by Kernel Concurrency Sanitizer on:
[ 45.015904][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0
[ 45.022992][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 45.033212][ C1] ==================================================================
[ 45.041251][ C1] Kernel panic - not syncing: panic_on_warn set ...
[ 45.047836][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0
[ 45.054922][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 45.064955][ C1] Call Trace:
[ 45.068219][ C1]
[ 45.071063][ C1] dump_stack+0xf5/0x159
[ 45.075289][ C1] panic+0x210/0x640
[ 45.079172][ C1] ? __netif_receive_skb+0x37/0xf0
[ 45.084381][ C1] ? vprintk_func+0x8d/0x140
[ 45.088967][ C1] kcsan_report.cold+0xc/0x10
[ 45.093632][ C1] __kcsan_setup_watchpoint+0x32e/0x4a0
[ 45.099172][ C1] __tsan_write4+0x32/0x40
[ 45.103576][ C1] tcp_add_backlog+0x4a0/0xcc0
[ 45.108334][ C1] tcp_v4_rcv+0x1a60/0x1bb0
[ 45.112832][ C1] ? __tsan_read8+0x2c/0x30
[ 45.117346][ C1] ip_protocol_deliver_rcu+0x4d/0x420
[ 45.122703][ C1] ip_local_deliver_finish+0x110/0x140
[ 45.128146][ C1] ip_local_deliver+0x133/0x210
[ 45.132981][ C1] ? ip_protocol_deliver_rcu+0x420/0x420
[ 45.138599][ C1] ip_rcv_finish+0x121/0x160
[ 45.143176][ C1] ip_rcv+0x18f/0x1a0
[ 45.147141][ C1] ? ip_sublist_rcv+0x5e0/0x5e0
[ 45.151973][ C1] ? ip_local_deliver+0x210/0x210
[ 45.156987][ C1] __netif_receive_skb_one_core+0xa7/0xe0
[ 45.162691][ C1] __netif_receive_skb+0x37/0xf0
[ 45.167627][ C1] netif_receive_skb_internal+0x59/0x190
[ 45.173248][ C1] napi_gro_receive+0x28f/0x330
[ 45.178176][ C1] receive_buf+0x284/0x30b0
[ 45.182664][ C1] ? __tsan_write8+0x32/0x40
[ 45.187247][ C1] ? virtqueue_get_buf_ctx+0x4fd/0x5c0
[ 45.192689][ C1] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 45.198303][ C1] ? __kcsan_setup_watchpoint+0x6b/0x4a0
[ 45.203923][ C1] virtnet_poll+0x436/0x7d0
[ 45.208421][ C1] ? common_interrupt+0xa/0xf
[ 45.213111][ C1] net_rx_action+0x3ae/0xa90
[ 45.217691][ C1] __do_softirq+0x115/0x33f
[ 45.222187][ C1] irq_exit+0xbb/0xe0
[ 45.226153][ C1] do_IRQ+0xa6/0x180
[ 45.230035][ C1] common_interrupt+0xf/0xf
[ 45.234513][ C1]
[ 45.237460][ C1] RIP: 0010:native_safe_halt+0xe/0x10
[ 45.242824][ C1] 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
[ 45.262417][ C1] RSP: 0018:ffffc90000cd3e48 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffde
[ 45.270812][ C1] RAX: 47ae147ae147ca49 RBX: ffff88812b3850c0 RCX: 0000000000000231
[ 45.278775][ C1] RDX: 00000000001879a0 RSI: 020c49ba5e353f7d RDI: ffffffff85a563b8
[ 45.286730][ C1] RBP: ffffc90000cd3e80 R08: 0000000000000000 R09: 0000ffff85a563bf
[ 45.294685][ C1] R10: 00000000aaaaaaab R11: ffffffff86045cc8 R12: 0000000000000001
[ 45.302643][ C1] R13: ffff88812b3850c0 R14: 0000000000000000 R15: 0000000000000000
[ 45.310626][ C1] ? default_idle+0x50/0x230
[ 45.315208][ C1] arch_cpu_idle+0x1f/0x30
[ 45.319613][ C1] default_idle_call+0x1e/0x40
[ 45.324364][ C1] do_idle+0x1af/0x280
[ 45.328431][ C1] ? complete+0x44/0x50
[ 45.332609][ C1] cpu_startup_entry+0x1b/0x20
[ 45.337366][ C1] start_secondary+0x208/0x260
[ 45.342120][ C1] secondary_startup_64+0xa4/0xb0
[ 45.348485][ C1] Kernel Offset: disabled
[ 45.352805][ C1] Rebooting in 86400 seconds..