[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.047274][ T26] audit: type=1800 audit(1570192780.850:25): pid=6989 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.067011][ T26] audit: type=1800 audit(1570192780.850:26): pid=6989 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.088642][ T26] audit: type=1800 audit(1570192780.850:27): pid=6989 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 '10.128.0.94' (ECDSA) to the list of known hosts. 2019/10/04 12:39:51 fuzzer started 2019/10/04 12:39:53 dialing manager at 10.128.0.105:38119 2019/10/04 12:39:53 syscalls: 2523 2019/10/04 12:39:53 code coverage: enabled 2019/10/04 12:39:53 comparison tracing: enabled 2019/10/04 12:39:53 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:39:53 setuid sandbox: enabled 2019/10/04 12:39:53 namespace sandbox: enabled 2019/10/04 12:39:53 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:39:53 fault injection: enabled 2019/10/04 12:39:53 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:39:53 net packet injection: enabled 2019/10/04 12:39:53 net device setup: enabled 2019/10/04 12:39:53 concurrency sanitizer: enabled syzkaller login: [ 50.609973][ C1] ================================================================== [ 50.618175][ C1] BUG: KCSAN: data-race in tcp_add_backlog+0x4a0/0xcc0 and tcp_grow_window.isra.0+0x6b/0x480 [ 50.628295][ C1] [ 50.630616][ C1] read to 0xffff8881293ec12c of 4 bytes by task 7148 on cpu 0: [ 50.638151][ C1] tcp_grow_window.isra.0+0x6b/0x480 [ 50.643592][ C1] tcp_event_data_recv+0x68f/0x990 [ 50.648687][ C1] tcp_rcv_established+0xbfe/0xf50 [ 50.653777][ C1] tcp_v4_do_rcv+0x381/0x4e0 [ 50.658351][ C1] __release_sock+0x135/0x1e0 [ 50.663015][ C1] release_sock+0x61/0x160 [ 50.667412][ C1] tcp_recvmsg+0x63b/0x1a30 [ 50.671897][ C1] inet_recvmsg+0xbb/0x250 [ 50.676293][ C1] sock_recvmsg+0x92/0xb0 [ 50.680604][ C1] sock_read_iter+0x15f/0x1e0 [ 50.685267][ C1] new_sync_read+0x389/0x4f0 [ 50.689841][ C1] __vfs_read+0xb1/0xc0 [ 50.693983][ C1] vfs_read+0x143/0x2c0 [ 50.698128][ C1] ksys_read+0xd5/0x1b0 [ 50.702276][ C1] [ 50.704588][ C1] write to 0xffff8881293ec12c of 4 bytes by interrupt on cpu 1: [ 50.712282][ C1] tcp_add_backlog+0x4a0/0xcc0 [ 50.717025][ C1] tcp_v4_rcv+0x1aba/0x1bf0 [ 50.721525][ C1] ip_protocol_deliver_rcu+0x51/0x470 [ 50.726879][ C1] ip_local_deliver_finish+0x110/0x140 [ 50.732336][ C1] ip_local_deliver+0x133/0x210 [ 50.737166][ C1] ip_rcv_finish+0x121/0x160 [ 50.741749][ C1] ip_rcv+0x18f/0x1a0 [ 50.745715][ C1] __netif_receive_skb_one_core+0xa7/0xe0 [ 50.751418][ C1] __netif_receive_skb+0x37/0xf0 [ 50.756341][ C1] netif_receive_skb_internal+0x59/0x190 [ 50.761955][ C1] napi_gro_receive+0x28f/0x330 [ 50.766792][ C1] receive_buf+0x284/0x30b0 [ 50.771274][ C1] virtnet_poll+0x436/0x7d0 [ 50.775749][ C1] [ 50.778054][ C1] Reported by Kernel Concurrency Sanitizer on: [ 50.784189][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 50.791187][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.801232][ C1] ================================================================== [ 50.809269][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 50.815839][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 50.822834][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.832864][ C1] Call Trace: [ 50.836154][ C1] dump_stack+0xf5/0x159 [ 50.840380][ C1] panic+0x209/0x639 [ 50.844372][ C1] ? vprintk_func+0x8d/0x140 [ 50.848960][ C1] kcsan_report.cold+0x57/0xeb [ 50.853714][ C1] __kcsan_setup_watchpoint+0x342/0x500 [ 50.859242][ C1] __tsan_write4+0x32/0x40 [ 50.863640][ C1] tcp_add_backlog+0x4a0/0xcc0 [ 50.868386][ C1] ? __rcu_read_unlock+0x62/0xe0 [ 50.873312][ C1] tcp_v4_rcv+0x1aba/0x1bf0 [ 50.877797][ C1] ? __tsan_read8+0x2c/0x30 [ 50.882305][ C1] ip_protocol_deliver_rcu+0x51/0x470 [ 50.887679][ C1] ip_local_deliver_finish+0x110/0x140 [ 50.893125][ C1] ip_local_deliver+0x133/0x210 [ 50.897960][ C1] ? ip_protocol_deliver_rcu+0x470/0x470 [ 50.903578][ C1] ip_rcv_finish+0x121/0x160 [ 50.908153][ C1] ip_rcv+0x18f/0x1a0 [ 50.912119][ C1] ? ip_sublist_rcv+0x5e0/0x5e0 [ 50.916953][ C1] ? ip_local_deliver+0x210/0x210 [ 50.921964][ C1] __netif_receive_skb_one_core+0xa7/0xe0 [ 50.927675][ C1] __netif_receive_skb+0x37/0xf0 [ 50.932597][ C1] netif_receive_skb_internal+0x59/0x190 [ 50.938232][ C1] napi_gro_receive+0x28f/0x330 [ 50.943070][ C1] receive_buf+0x284/0x30b0 [ 50.947562][ C1] ? __tsan_write8+0x32/0x40 [ 50.952144][ C1] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 50.957587][ C1] ? virtqueue_get_buf+0x31/0x40 [ 50.962513][ C1] virtnet_poll+0x436/0x7d0 [ 50.967011][ C1] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 50.973242][ C1] net_rx_action+0x3ae/0xa50 [ 50.977826][ C1] __do_softirq+0x115/0x33f [ 50.982403][ C1] ? takeover_tasklets+0x250/0x250 [ 50.987497][ C1] run_ksoftirqd+0x46/0x60 [ 50.991895][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 50.996817][ C1] kthread+0x1d4/0x200 [ 51.000868][ C1] ? constant_test_bit.constprop.0+0x30/0x30 [ 51.006829][ C1] ? kthread_bind+0x50/0x50 [ 51.011326][ C1] ret_from_fork+0x1f/0x30 [ 51.017041][ C1] Kernel Offset: disabled [ 51.021359][ C1] Rebooting in 86400 seconds..