[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 42.412680][ T26] audit: type=1800 audit(1571788647.504:25): pid=7077 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 42.432758][ T26] audit: type=1800 audit(1571788647.504:26): pid=7077 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 42.464058][ T26] audit: type=1800 audit(1571788647.504:27): pid=7077 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 '10.128.0.132' (ECDSA) to the list of known hosts. 2019/10/22 23:57:39 fuzzer started 2019/10/22 23:57:40 dialing manager at 10.128.0.105:33369 2019/10/22 23:57:40 syscalls: 2524 2019/10/22 23:57:40 code coverage: enabled 2019/10/22 23:57:40 comparison tracing: enabled 2019/10/22 23:57:40 extra coverage: extra coverage is not supported by the kernel 2019/10/22 23:57:40 setuid sandbox: enabled 2019/10/22 23:57:40 namespace sandbox: enabled 2019/10/22 23:57:40 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 23:57:40 fault injection: enabled 2019/10/22 23:57:40 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 23:57:40 net packet injection: enabled 2019/10/22 23:57:40 net device setup: enabled 2019/10/22 23:57:40 concurrency sanitizer: enabled syzkaller login: [ 56.996021][ T7240] ================================================================== [ 57.007202][ T7240] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 57.016653][ T7240] [ 57.019171][ T7240] read to 0xffff88811dc8a308 of 4 bytes by interrupt on cpu 1: [ 57.027641][ T7240] __nf_conntrack_find_get+0x284/0x880 [ 57.033948][ T7240] nf_conntrack_in+0x2ef/0xa80 [ 57.038881][ T7240] ipv4_conntrack_in+0x27/0x40 [ 57.044172][ T7240] nf_hook_slow+0x83/0x160 [ 57.049224][ T7240] ip_rcv+0x12f/0x1a0 [ 57.053564][ T7240] __netif_receive_skb_one_core+0xa7/0xe0 [ 57.059583][ T7240] __netif_receive_skb+0x37/0xf0 [ 57.065209][ T7240] netif_receive_skb_internal+0x59/0x190 [ 57.072395][ T7240] napi_gro_receive+0x28f/0x330 [ 57.079961][ T7240] receive_buf+0x284/0x30b0 [ 57.087145][ T7240] virtnet_poll+0x436/0x7d0 [ 57.092242][ T7240] net_rx_action+0x3ae/0xa90 [ 57.097458][ T7240] __do_softirq+0x115/0x33f [ 57.102419][ T7240] run_ksoftirqd+0x46/0x60 [ 57.107106][ T7240] [ 57.110852][ T7240] write to 0xffff88811dc8a308 of 4 bytes by task 7240 on cpu 0: [ 57.119003][ T7240] __nf_ct_refresh_acct+0xfb/0x1b0 [ 57.124198][ T7240] nf_conntrack_tcp_packet+0xd40/0x3390 [ 57.130491][ T7240] nf_conntrack_in+0x410/0xa80 [ 57.135320][ T7240] ipv4_conntrack_local+0xbe/0x130 [ 57.141285][ T7240] nf_hook_slow+0x83/0x160 [ 57.145860][ T7240] __ip_local_out+0x1f7/0x2b0 [ 57.150830][ T7240] ip_local_out+0x31/0x90 [ 57.155618][ T7240] __ip_queue_xmit+0x3a8/0xa40 [ 57.160750][ T7240] ip_queue_xmit+0x45/0x60 [ 57.165189][ T7240] __tcp_transmit_skb+0xe81/0x1d60 [ 57.171581][ T7240] __tcp_send_ack+0x246/0x300 [ 57.177213][ T7240] tcp_send_ack+0x34/0x40 [ 57.182562][ T7240] tcp_cleanup_rbuf+0x130/0x360 [ 57.188202][ T7240] [ 57.190863][ T7240] Reported by Kernel Concurrency Sanitizer on: [ 57.198107][ T7240] CPU: 0 PID: 7240 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 57.206032][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.216340][ T7240] ================================================================== [ 57.225049][ T7240] Kernel panic - not syncing: panic_on_warn set ... [ 57.231973][ T7240] CPU: 0 PID: 7240 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 57.239843][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.250235][ T7240] Call Trace: [ 57.254060][ T7240] dump_stack+0xf5/0x159 [ 57.259392][ T7240] panic+0x210/0x640 [ 57.263805][ T7240] ? ip_queue_xmit+0x45/0x60 [ 57.269345][ T7240] ? vprintk_func+0x8d/0x140 [ 57.274523][ T7240] kcsan_report.cold+0xc/0x10 [ 57.279604][ T7240] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 57.286323][ T7240] __tsan_write4+0x32/0x40 [ 57.291242][ T7240] __nf_ct_refresh_acct+0xfb/0x1b0 [ 57.296559][ T7240] nf_conntrack_tcp_packet+0xd40/0x3390 [ 57.303041][ T7240] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 57.308979][ T7240] nf_conntrack_in+0x410/0xa80 [ 57.314061][ T7240] ipv4_conntrack_local+0xbe/0x130 [ 57.319298][ T7240] nf_hook_slow+0x83/0x160 [ 57.324100][ T7240] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 57.328965][ T7240] __ip_local_out+0x1f7/0x2b0 [ 57.333855][ T7240] ? constant_test_bit+0x30/0x30 [ 57.339079][ T7240] ip_local_out+0x31/0x90 [ 57.344040][ T7240] __ip_queue_xmit+0x3a8/0xa40 [ 57.349162][ T7240] ip_queue_xmit+0x45/0x60 [ 57.353671][ T7240] __tcp_transmit_skb+0xe81/0x1d60 [ 57.358902][ T7240] __tcp_send_ack+0x246/0x300 [ 57.364037][ T7240] tcp_send_ack+0x34/0x40 [ 57.368858][ T7240] tcp_cleanup_rbuf+0x130/0x360 [ 57.374454][ T7240] tcp_recvmsg+0x633/0x1a30 [ 57.379416][ T7240] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 57.385876][ T7240] inet_recvmsg+0xbb/0x250 [ 57.391318][ T7240] ? __tsan_read8+0x2c/0x30 [ 57.396499][ T7240] ? inet_sendpage+0x100/0x100 [ 57.401609][ T7240] sock_recvmsg+0x92/0xb0 [ 57.406168][ T7240] sock_read_iter+0x15f/0x1e0 [ 57.412580][ T7240] new_sync_read+0x389/0x4f0 [ 57.418563][ T7240] __vfs_read+0xb1/0xc0 [ 57.423200][ T7240] vfs_read+0x143/0x2c0 [ 57.427412][ T7240] ksys_read+0xd5/0x1b0 [ 57.431941][ T7240] __x64_sys_read+0x4c/0x60 [ 57.436868][ T7240] do_syscall_64+0xcc/0x370 [ 57.441992][ T7240] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 57.448675][ T7240] RIP: 0033:0x47c530 [ 57.452570][ T7240] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 57.473016][ T7240] RSP: 002b:000000c4200517d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 57.483339][ T7240] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 57.491764][ T7240] RDX: 0000000000001000 RSI: 000000c4203a0000 RDI: 0000000000000003 [ 57.500912][ T7240] RBP: 000000c420051830 R08: 0000000000000000 R09: 0000000000000000 [ 57.510972][ T7240] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 57.519588][ T7240] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 57.530317][ T7240] Kernel Offset: disabled [ 57.535047][ T7240] Rebooting in 86400 seconds..