[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.366650][ T25] audit: type=1800 audit(1570319965.747:25): pid=7034 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.402215][ T25] audit: type=1800 audit(1570319965.747:26): pid=7034 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.430894][ T25] audit: type=1800 audit(1570319965.747:27): pid=7034 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 '10.128.0.49' (ECDSA) to the list of known hosts. 2019/10/05 23:59:36 fuzzer started 2019/10/05 23:59:38 dialing manager at 10.128.0.105:35709 2019/10/05 23:59:38 syscalls: 2523 2019/10/05 23:59:38 code coverage: enabled 2019/10/05 23:59:38 comparison tracing: enabled 2019/10/05 23:59:38 extra coverage: extra coverage is not supported by the kernel 2019/10/05 23:59:38 setuid sandbox: enabled 2019/10/05 23:59:38 namespace sandbox: enabled 2019/10/05 23:59:38 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/05 23:59:38 fault injection: enabled 2019/10/05 23:59:38 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/05 23:59:38 net packet injection: enabled 2019/10/05 23:59:38 net device setup: enabled 2019/10/05 23:59:38 concurrency sanitizer: enabled syzkaller login: [ 48.078248][ C0] ================================================================== [ 48.086411][ C0] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 48.094188][ C0] [ 48.096503][ C0] write to 0xffff888123f2e14c of 4 bytes by task 7196 on cpu 1: [ 48.104113][ C0] tcp_rcv_space_adjust+0x40f/0x4c0 [ 48.109289][ C0] tcp_recvmsg+0xdaa/0x1a30 [ 48.113773][ C0] inet_recvmsg+0xbb/0x250 [ 48.118170][ C0] sock_recvmsg+0x92/0xb0 [ 48.122478][ C0] sock_read_iter+0x15f/0x1e0 [ 48.127135][ C0] new_sync_read+0x389/0x4f0 [ 48.131707][ C0] __vfs_read+0xb1/0xc0 [ 48.135844][ C0] vfs_read+0x143/0x2c0 [ 48.139981][ C0] ksys_read+0xd5/0x1b0 [ 48.144118][ C0] __x64_sys_read+0x4c/0x60 [ 48.148613][ C0] do_syscall_64+0xcf/0x2f0 [ 48.153110][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.158971][ C0] [ 48.161280][ C0] read to 0xffff888123f2e14c of 4 bytes by interrupt on cpu 0: [ 48.168799][ C0] tcp_add_backlog+0x43/0xcc0 [ 48.173454][ C0] tcp_v4_rcv+0x1aba/0x1bf0 [ 48.177946][ C0] ip_protocol_deliver_rcu+0x51/0x470 [ 48.183295][ C0] ip_local_deliver_finish+0x110/0x140 [ 48.188731][ C0] ip_local_deliver+0x133/0x210 [ 48.193563][ C0] ip_rcv_finish+0x121/0x160 [ 48.198141][ C0] ip_rcv+0x18f/0x1a0 [ 48.202105][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.207804][ C0] __netif_receive_skb+0x37/0xf0 [ 48.212726][ C0] netif_receive_skb_internal+0x59/0x190 [ 48.218336][ C0] napi_gro_receive+0x28f/0x330 [ 48.225163][ C0] receive_buf+0x284/0x30b0 [ 48.229647][ C0] virtnet_poll+0x436/0x7d0 [ 48.234120][ C0] [ 48.236423][ C0] Reported by Kernel Concurrency Sanitizer on: [ 48.242558][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.3.0+ #0 [ 48.249469][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.259502][ C0] ================================================================== [ 48.267540][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 48.274107][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.3.0+ #0 [ 48.281017][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.291055][ C0] Call Trace: [ 48.294330][ C0] dump_stack+0xf5/0x159 [ 48.298560][ C0] panic+0x209/0x639 [ 48.302438][ C0] ? vprintk_func+0x8d/0x140 [ 48.307016][ C0] kcsan_report.cold+0x57/0xeb [ 48.311762][ C0] __kcsan_setup_watchpoint+0x342/0x500 [ 48.317287][ C0] __tsan_read4+0x2c/0x30 [ 48.321597][ C0] tcp_add_backlog+0x43/0xcc0 [ 48.326259][ C0] ? __rcu_read_unlock+0x62/0xe0 [ 48.331182][ C0] ? sk_filter_trim_cap+0x230/0x520 [ 48.336365][ C0] ? __tsan_write1+0x32/0x40 [ 48.340938][ C0] tcp_v4_rcv+0x1aba/0x1bf0 [ 48.345423][ C0] ? __tsan_read8+0x2c/0x30 [ 48.349914][ C0] ip_protocol_deliver_rcu+0x51/0x470 [ 48.355273][ C0] ip_local_deliver_finish+0x110/0x140 [ 48.360716][ C0] ip_local_deliver+0x133/0x210 [ 48.365558][ C0] ? ip_protocol_deliver_rcu+0x470/0x470 [ 48.371173][ C0] ip_rcv_finish+0x121/0x160 [ 48.375746][ C0] ip_rcv+0x18f/0x1a0 [ 48.379709][ C0] ? ip_sublist_rcv+0x5e0/0x5e0 [ 48.384543][ C0] ? ip_local_deliver+0x210/0x210 [ 48.389552][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.395267][ C0] __netif_receive_skb+0x37/0xf0 [ 48.400186][ C0] netif_receive_skb_internal+0x59/0x190 [ 48.405800][ C0] napi_gro_receive+0x28f/0x330 [ 48.410635][ C0] receive_buf+0x284/0x30b0 [ 48.415119][ C0] ? __tsan_write8+0x32/0x40 [ 48.419698][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 48.425139][ C0] ? virtqueue_get_buf+0x31/0x40 [ 48.430061][ C0] virtnet_poll+0x436/0x7d0 [ 48.434551][ C0] net_rx_action+0x3ae/0xa50 [ 48.439130][ C0] __do_softirq+0x115/0x33f [ 48.443619][ C0] ? takeover_tasklets+0x250/0x250 [ 48.448713][ C0] run_ksoftirqd+0x46/0x60 [ 48.453111][ C0] smpboot_thread_fn+0x37d/0x4a0 [ 48.458032][ C0] kthread+0x1d4/0x200 [ 48.462084][ C0] ? constant_test_bit.constprop.0+0x30/0x30 [ 48.468475][ C0] ? kthread_bind+0x50/0x50 [ 48.472961][ C0] ret_from_fork+0x1f/0x30 [ 48.478484][ C0] Kernel Offset: disabled [ 48.482803][ C0] Rebooting in 86400 seconds..