[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.093779][ T26] audit: type=1800 audit(1570192448.722:25): pid=7205 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.122534][ T26] audit: type=1800 audit(1570192448.722:26): pid=7205 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.151253][ T26] audit: type=1800 audit(1570192448.722:27): pid=7205 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 '10.128.10.23' (ECDSA) to the list of known hosts. 2019/10/04 12:34:19 fuzzer started 2019/10/04 12:34:21 dialing manager at 10.128.0.105:38119 2019/10/04 12:34:21 syscalls: 2523 2019/10/04 12:34:21 code coverage: enabled 2019/10/04 12:34:21 comparison tracing: enabled 2019/10/04 12:34:21 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:34:21 setuid sandbox: enabled 2019/10/04 12:34:21 namespace sandbox: enabled 2019/10/04 12:34:21 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:34:21 fault injection: enabled 2019/10/04 12:34:21 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:34:21 net packet injection: enabled 2019/10/04 12:34:21 net device setup: enabled 2019/10/04 12:34:21 concurrency sanitizer: enabled syzkaller login: [ 49.319587][ C1] ================================================================== [ 49.328053][ C1] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 49.337592][ C1] [ 49.339929][ C1] read to 0xffff8881243272f8 of 8 bytes by task 7362 on cpu 0: [ 49.347651][ C1] tcp_recvmsg+0x470/0x1a30 [ 49.353408][ C1] inet_recvmsg+0xbb/0x250 [ 49.357820][ C1] sock_recvmsg+0x92/0xb0 [ 49.362146][ C1] sock_read_iter+0x15f/0x1e0 [ 49.366827][ C1] new_sync_read+0x389/0x4f0 [ 49.371404][ C1] __vfs_read+0xb1/0xc0 [ 49.375544][ C1] vfs_read+0x143/0x2c0 [ 49.379688][ C1] ksys_read+0xd5/0x1b0 [ 49.384035][ C1] __x64_sys_read+0x4c/0x60 [ 49.388787][ C1] do_syscall_64+0xcf/0x2f0 [ 49.393280][ C1] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.399153][ C1] [ 49.401477][ C1] write to 0xffff8881243272f8 of 8 bytes by interrupt on cpu 1: [ 49.409211][ C1] tcp_add_backlog+0x45a/0xcc0 [ 49.413962][ C1] tcp_v4_rcv+0x1aba/0x1bf0 [ 49.418456][ C1] ip_protocol_deliver_rcu+0x51/0x470 [ 49.424276][ C1] ip_local_deliver_finish+0x110/0x140 [ 49.430199][ C1] ip_local_deliver+0x133/0x210 [ 49.435037][ C1] ip_rcv_finish+0x121/0x160 [ 49.439622][ C1] ip_rcv+0x18f/0x1a0 [ 49.444043][ C1] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.449774][ C1] __netif_receive_skb+0x37/0xf0 [ 49.454705][ C1] netif_receive_skb_internal+0x59/0x190 [ 49.460336][ C1] napi_gro_receive+0x28f/0x330 [ 49.465174][ C1] receive_buf+0x284/0x30b0 [ 49.469663][ C1] virtnet_poll+0x436/0x7d0 [ 49.474146][ C1] [ 49.476458][ C1] Reported by Kernel Concurrency Sanitizer on: [ 49.482606][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 49.489630][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.499932][ C1] ================================================================== [ 49.507988][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 49.514682][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 49.521909][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.532128][ C1] Call Trace: [ 49.536628][ C1] dump_stack+0xf5/0x159 [ 49.541046][ C1] panic+0x209/0x639 [ 49.545057][ C1] ? vprintk_func+0x8d/0x140 [ 49.549747][ C1] kcsan_report.cold+0x57/0xeb [ 49.554853][ C1] __kcsan_setup_watchpoint+0x342/0x500 [ 49.560997][ C1] __tsan_write8+0x32/0x40 [ 49.565405][ C1] tcp_add_backlog+0x45a/0xcc0 [ 49.570170][ C1] ? __rcu_read_unlock+0x62/0xe0 [ 49.575121][ C1] tcp_v4_rcv+0x1aba/0x1bf0 [ 49.579971][ C1] ? __tsan_read8+0x2c/0x30 [ 49.584593][ C1] ip_protocol_deliver_rcu+0x51/0x470 [ 49.590164][ C1] ip_local_deliver_finish+0x110/0x140 [ 49.597237][ C1] ip_local_deliver+0x133/0x210 [ 49.602532][ C1] ? ip_protocol_deliver_rcu+0x470/0x470 [ 49.608877][ C1] ip_rcv_finish+0x121/0x160 [ 49.613723][ C1] ip_rcv+0x18f/0x1a0 [ 49.619970][ C1] ? ip_sublist_rcv+0x5e0/0x5e0 [ 49.624897][ C1] ? ip_local_deliver+0x210/0x210 [ 49.630001][ C1] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.636322][ C1] __netif_receive_skb+0x37/0xf0 [ 49.641336][ C1] netif_receive_skb_internal+0x59/0x190 [ 49.646965][ C1] napi_gro_receive+0x28f/0x330 [ 49.653196][ C1] receive_buf+0x284/0x30b0 [ 49.657700][ C1] ? __tsan_write8+0x32/0x40 [ 49.662294][ C1] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 49.667752][ C1] ? virtqueue_get_buf+0x31/0x40 [ 49.673088][ C1] virtnet_poll+0x436/0x7d0 [ 49.677599][ C1] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 49.683847][ C1] net_rx_action+0x3ae/0xa50 [ 49.688440][ C1] __do_softirq+0x115/0x33f [ 49.693360][ C1] ? takeover_tasklets+0x250/0x250 [ 49.700045][ C1] run_ksoftirqd+0x46/0x60 [ 49.704451][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 49.709493][ C1] kthread+0x1d4/0x200 [ 49.713551][ C1] ? constant_test_bit.constprop.0+0x30/0x30 [ 49.719519][ C1] ? kthread_bind+0x50/0x50 [ 49.724042][ C1] ret_from_fork+0x1f/0x30 [ 49.729941][ C1] Kernel Offset: disabled [ 49.734265][ C1] Rebooting in 86400 seconds..