[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.830197][ T26] audit: type=1800 audit(1571754682.742:25): pid=7027 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.856303][ T26] audit: type=1800 audit(1571754682.742:26): pid=7027 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.884636][ T26] audit: type=1800 audit(1571754682.742:27): pid=7027 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 '10.128.1.15' (ECDSA) to the list of known hosts. 2019/10/22 14:31:33 fuzzer started 2019/10/22 14:31:34 dialing manager at 10.128.0.105:33369 2019/10/22 14:31:34 syscalls: 2524 2019/10/22 14:31:34 code coverage: enabled 2019/10/22 14:31:34 comparison tracing: enabled 2019/10/22 14:31:34 extra coverage: extra coverage is not supported by the kernel 2019/10/22 14:31:34 setuid sandbox: enabled 2019/10/22 14:31:34 namespace sandbox: enabled 2019/10/22 14:31:34 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 14:31:34 fault injection: enabled 2019/10/22 14:31:34 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 14:31:34 net packet injection: enabled 2019/10/22 14:31:34 net device setup: enabled 2019/10/22 14:31:34 concurrency sanitizer: enabled syzkaller login: [ 48.315263][ C0] ================================================================== [ 48.323387][ C0] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 48.331856][ C0] [ 48.334161][ C0] write to 0xffff88812470e108 of 4 bytes by task 7183 on cpu 1: [ 48.341775][ C0] __nf_ct_refresh_acct+0xfb/0x1b0 [ 48.346870][ C0] nf_conntrack_tcp_packet+0xd40/0x3390 [ 48.352398][ C0] nf_conntrack_in+0x410/0xa80 [ 48.357148][ C0] ipv4_conntrack_local+0xbe/0x130 [ 48.362238][ C0] nf_hook_slow+0x83/0x160 [ 48.366715][ C0] __ip_local_out+0x1f7/0x2b0 [ 48.371363][ C0] ip_local_out+0x31/0x90 [ 48.375664][ C0] __ip_queue_xmit+0x3a8/0xa40 [ 48.380489][ C0] ip_queue_xmit+0x45/0x60 [ 48.384894][ C0] __tcp_transmit_skb+0xe81/0x1d60 [ 48.389977][ C0] __tcp_send_ack+0x246/0x300 [ 48.394624][ C0] tcp_send_ack+0x34/0x40 [ 48.398939][ C0] tcp_cleanup_rbuf+0x130/0x360 [ 48.403762][ C0] tcp_recvmsg+0x633/0x1a30 [ 48.408236][ C0] [ 48.410550][ C0] read to 0xffff88812470e108 of 4 bytes by interrupt on cpu 0: [ 48.418066][ C0] __nf_conntrack_find_get+0x284/0x880 [ 48.423499][ C0] nf_conntrack_in+0x2ef/0xa80 [ 48.428238][ C0] ipv4_conntrack_in+0x27/0x40 [ 48.432985][ C0] nf_hook_slow+0x83/0x160 [ 48.437384][ C0] ip_rcv+0x12f/0x1a0 [ 48.441339][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.447042][ C0] __netif_receive_skb+0x37/0xf0 [ 48.451952][ C0] netif_receive_skb_internal+0x59/0x190 [ 48.457568][ C0] napi_gro_receive+0x28f/0x330 [ 48.462401][ C0] receive_buf+0x284/0x30b0 [ 48.466878][ C0] virtnet_poll+0x436/0x7d0 [ 48.471366][ C0] net_rx_action+0x3ae/0xa90 [ 48.475940][ C0] __do_softirq+0x115/0x33f [ 48.480409][ C0] [ 48.482712][ C0] Reported by Kernel Concurrency Sanitizer on: [ 48.488840][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 48.496089][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.506123][ C0] ================================================================== [ 48.514154][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 48.520722][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc3+ #0 [ 48.527974][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.538002][ C0] Call Trace: [ 48.541281][ C0] dump_stack+0xf5/0x159 [ 48.545501][ C0] panic+0x210/0x640 [ 48.549375][ C0] ? napi_gro_receive+0x28f/0x330 [ 48.554377][ C0] ? vprintk_func+0x8d/0x140 [ 48.558942][ C0] kcsan_report.cold+0xc/0x10 [ 48.563595][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.569117][ C0] __tsan_read4+0x2c/0x30 [ 48.573426][ C0] __nf_conntrack_find_get+0x284/0x880 [ 48.578866][ C0] ? __tsan_write2+0x32/0x40 [ 48.583432][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.589046][ C0] nf_conntrack_in+0x2ef/0xa80 [ 48.593789][ C0] ipv4_conntrack_in+0x27/0x40 [ 48.598530][ C0] nf_hook_slow+0x83/0x160 [ 48.602931][ C0] ? nf_ct_bridge_unregister+0x70/0x70 [ 48.608364][ C0] ip_rcv+0x12f/0x1a0 [ 48.612323][ C0] ? ip_sublist_rcv+0x5e0/0x5e0 [ 48.617147][ C0] ? ip_local_deliver+0x210/0x210 [ 48.622152][ C0] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.627846][ C0] __netif_receive_skb+0x37/0xf0 [ 48.632777][ C0] netif_receive_skb_internal+0x59/0x190 [ 48.638397][ C0] napi_gro_receive+0x28f/0x330 [ 48.643223][ C0] receive_buf+0x284/0x30b0 [ 48.647703][ C0] ? __tsan_write8+0x32/0x40 [ 48.652284][ C0] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 48.657734][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.663347][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.668968][ C0] virtnet_poll+0x436/0x7d0 [ 48.673470][ C0] net_rx_action+0x3ae/0xa90 [ 48.678043][ C0] __do_softirq+0x115/0x33f [ 48.682541][ C0] ? takeover_tasklets+0x250/0x250 [ 48.687628][ C0] run_ksoftirqd+0x46/0x60 [ 48.692019][ C0] smpboot_thread_fn+0x37d/0x4a0 [ 48.696933][ C0] kthread+0x1d4/0x200 [ 48.700980][ C0] ? constant_test_bit.constprop.0+0x30/0x30 [ 48.706933][ C0] ? kthread_stop+0x2d0/0x2d0 [ 48.711587][ C0] ret_from_fork+0x1f/0x30 [ 48.717256][ C0] Kernel Offset: disabled [ 48.721599][ C0] Rebooting in 86400 seconds..