[ 38.136522][ T26] audit: type=1800 audit(1571742651.174:25): pid=7107 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 38.179663][ T26] audit: type=1800 audit(1571742651.184:26): pid=7107 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 38.200585][ T26] audit: type=1800 audit(1571742651.184:27): pid=7107 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. [ 38.475693][ T7175] sshd (7175) used greatest stack depth: 10136 bytes left [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.158' (ECDSA) to the list of known hosts. 2019/10/22 11:10:59 fuzzer started 2019/10/22 11:11:00 dialing manager at 10.128.0.105:37053 2019/10/22 11:11:00 syscalls: 2524 2019/10/22 11:11:00 code coverage: enabled 2019/10/22 11:11:00 comparison tracing: enabled 2019/10/22 11:11:00 extra coverage: extra coverage is not supported by the kernel 2019/10/22 11:11:00 setuid sandbox: enabled 2019/10/22 11:11:00 namespace sandbox: enabled 2019/10/22 11:11:00 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 11:11:00 fault injection: enabled 2019/10/22 11:11:00 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 11:11:00 net packet injection: enabled 2019/10/22 11:11:00 net device setup: enabled 2019/10/22 11:11:00 concurrency sanitizer: enabled syzkaller login: [ 48.877230][ C0] ================================================================== [ 48.885446][ C0] BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv [ 48.892347][ C0] [ 48.894665][ C0] read to 0xffff8881203be5b8 of 4 bytes by task 7260 on cpu 1: [ 48.902306][ C0] tcp_poll+0x204/0x6b0 [ 48.907086][ C0] sock_poll+0xed/0x250 [ 48.911506][ C0] ep_item_poll.isra.0+0x90/0x190 [ 48.916550][ C0] ep_send_events_proc+0x113/0x590 [ 48.921660][ C0] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.928569][ C0] ep_poll+0xe3/0x900 [ 48.932802][ C0] do_epoll_wait+0x162/0x180 [ 48.937419][ C0] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.942626][ C0] do_syscall_64+0xcc/0x370 [ 48.947241][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.953124][ C0] [ 48.955549][ C0] write to 0xffff8881203be5b8 of 4 bytes by interrupt on cpu 0: [ 48.963168][ C0] tcp_queue_rcv+0x180/0x380 [ 48.969977][ C0] tcp_rcv_established+0xbf1/0xf50 [ 48.975094][ C0] tcp_v4_do_rcv+0x381/0x4e0 [ 48.979660][ C0] tcp_v4_rcv+0x19dc/0x1bb0 [ 48.984338][ C0] ip_protocol_deliver_rcu+0x4d/0x420 [ 48.989767][ C0] ip_local_deliver_finish+0x110/0x140 [ 48.995207][ C0] ip_local_deliver+0x133/0x210 [ 49.000353][ C0] ip_rcv_finish+0x121/0x160 [ 49.004943][ C0] ip_rcv+0x18f/0x1a0 [ 49.009024][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.014754][ C0] __netif_receive_skb+0x37/0xf0 [ 49.019786][ C0] netif_receive_skb_internal+0x59/0x190 [ 49.025443][ C0] napi_gro_receive+0x28f/0x330 [ 49.030861][ C0] [ 49.033192][ C0] Reported by Kernel Concurrency Sanitizer on: [ 49.039364][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 49.046653][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.056744][ C0] ================================================================== [ 49.064916][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 49.071548][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 49.078819][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.088869][ C0] Call Trace: [ 49.092177][ C0] dump_stack+0xf5/0x159 [ 49.096475][ C0] panic+0x210/0x640 [ 49.100401][ C0] ? ip_rcv+0x18f/0x1a0 [ 49.104554][ C0] ? vprintk_func+0x8d/0x140 [ 49.109134][ C0] kcsan_report.cold+0xc/0x10 [ 49.113848][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.119382][ C0] __tsan_write4+0x32/0x40 [ 49.123795][ C0] tcp_queue_rcv+0x180/0x380 [ 49.128382][ C0] tcp_rcv_established+0xbf1/0xf50 [ 49.133527][ C0] ? ipv4_dst_check+0xc6/0xf0 [ 49.138217][ C0] tcp_v4_do_rcv+0x381/0x4e0 [ 49.142797][ C0] tcp_v4_rcv+0x19dc/0x1bb0 [ 49.147290][ C0] ? __tsan_read8+0x2c/0x30 [ 49.152368][ C0] ip_protocol_deliver_rcu+0x4d/0x420 [ 49.158606][ C0] ip_local_deliver_finish+0x110/0x140 [ 49.164077][ C0] ip_local_deliver+0x133/0x210 [ 49.168911][ C0] ? ip_protocol_deliver_rcu+0x420/0x420 [ 49.174526][ C0] ip_rcv_finish+0x121/0x160 [ 49.179120][ C0] ip_rcv+0x18f/0x1a0 [ 49.183098][ C0] ? ip_sublist_rcv+0x5e0/0x5e0 [ 49.187940][ C0] ? ip_local_deliver+0x210/0x210 [ 49.192960][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.198780][ C0] __netif_receive_skb+0x37/0xf0 [ 49.203706][ C0] netif_receive_skb_internal+0x59/0x190 [ 49.209622][ C0] napi_gro_receive+0x28f/0x330 [ 49.214481][ C0] receive_buf+0x284/0x30b0 [ 49.218972][ C0] ? __tsan_write8+0x32/0x40 [ 49.223555][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 49.228996][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.234606][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.240244][ C0] virtnet_poll+0x436/0x7d0 [ 49.244766][ C0] net_rx_action+0x3ae/0xa90 [ 49.249454][ C0] __do_softirq+0x115/0x33f [ 49.254312][ C0] ? takeover_tasklets+0x250/0x250 [ 49.259405][ C0] run_ksoftirqd+0x46/0x60 [ 49.263810][ C0] smpboot_thread_fn+0x37d/0x4a0 [ 49.268752][ C0] kthread+0x1d4/0x200 [ 49.272818][ C0] ? constant_test_bit.constprop.0+0x30/0x30 [ 49.278775][ C0] ? kthread_stop+0x2d0/0x2d0 [ 49.283444][ C0] ret_from_fork+0x1f/0x30 [ 49.289514][ C0] Kernel Offset: disabled [ 49.293894][ C0] Rebooting in 86400 seconds..