[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.063059][ T23] audit: type=1800 audit(1570191887.339:25): pid=7128 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.114088][ T23] audit: type=1800 audit(1570191887.339:26): pid=7128 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.138668][ T23] audit: type=1800 audit(1570191887.339:27): pid=7128 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 '10.128.10.36' (ECDSA) to the list of known hosts. 2019/10/04 12:24:57 fuzzer started 2019/10/04 12:24:59 dialing manager at 10.128.0.105:38119 2019/10/04 12:24:59 syscalls: 2523 2019/10/04 12:24:59 code coverage: enabled 2019/10/04 12:24:59 comparison tracing: enabled 2019/10/04 12:24:59 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:24:59 setuid sandbox: enabled 2019/10/04 12:24:59 namespace sandbox: enabled 2019/10/04 12:24:59 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:24:59 fault injection: enabled 2019/10/04 12:24:59 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:24:59 net packet injection: enabled 2019/10/04 12:24:59 net device setup: enabled 2019/10/04 12:24:59 concurrency sanitizer: enabled syzkaller login: [ 49.064338][ T7293] ================================================================== [ 49.072608][ T7293] BUG: KCSAN: data-race in __nf_conntrack_find_get+0x284/0x870 and __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.083320][ T7293] [ 49.085629][ T7293] read to 0xffff888124e0c108 of 4 bytes by interrupt on cpu 0: [ 49.093195][ T7293] __nf_conntrack_find_get+0x284/0x870 [ 49.098640][ T7293] nf_conntrack_in+0x2ef/0xaa0 [ 49.103401][ T7293] ipv4_conntrack_in+0x27/0x40 [ 49.108157][ T7293] nf_hook_slow+0x83/0x160 [ 49.112602][ T7293] ip_rcv+0x12f/0x1a0 [ 49.116566][ T7293] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.122266][ T7293] __netif_receive_skb+0x37/0xf0 [ 49.127177][ T7293] netif_receive_skb_internal+0x59/0x190 [ 49.132793][ T7293] napi_gro_receive+0x28f/0x330 [ 49.137650][ T7293] receive_buf+0x284/0x30b0 [ 49.142151][ T7293] virtnet_poll+0x436/0x7d0 [ 49.146631][ T7293] net_rx_action+0x3ae/0xa50 [ 49.151197][ T7293] __do_softirq+0x115/0x33f [ 49.155678][ T7293] run_ksoftirqd+0x46/0x60 [ 49.160080][ T7293] [ 49.162389][ T7293] write to 0xffff888124e0c108 of 4 bytes by task 7293 on cpu 1: [ 49.170015][ T7293] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.175102][ T7293] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.180627][ T7293] nf_conntrack_in+0x410/0xaa0 [ 49.185365][ T7293] ipv4_conntrack_local+0xbe/0x130 [ 49.190455][ T7293] nf_hook_slow+0x83/0x160 [ 49.194862][ T7293] __ip_local_out+0x1f7/0x2b0 [ 49.199532][ T7293] ip_local_out+0x31/0x90 [ 49.203841][ T7293] __ip_queue_xmit+0x3a8/0xa40 [ 49.208583][ T7293] ip_queue_xmit+0x45/0x60 [ 49.212977][ T7293] __tcp_transmit_skb+0xdeb/0x1cd0 [ 49.218082][ T7293] __tcp_send_ack+0x246/0x300 [ 49.222738][ T7293] tcp_send_ack+0x34/0x40 [ 49.227056][ T7293] tcp_cleanup_rbuf+0x130/0x360 [ 49.231887][ T7293] [ 49.234201][ T7293] Reported by Kernel Concurrency Sanitizer on: [ 49.240334][ T7293] CPU: 1 PID: 7293 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.247542][ T7293] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.257592][ T7293] ================================================================== [ 49.265628][ T7293] Kernel panic - not syncing: panic_on_warn set ... [ 49.272193][ T7293] CPU: 1 PID: 7293 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.279274][ T7293] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.289327][ T7293] Call Trace: [ 49.292607][ T7293] dump_stack+0xf5/0x159 [ 49.296830][ T7293] panic+0x209/0x639 [ 49.300706][ T7293] ? vprintk_func+0x8d/0x140 [ 49.305277][ T7293] kcsan_report.cold+0x57/0xeb [ 49.310019][ T7293] __kcsan_setup_watchpoint+0x342/0x500 [ 49.315539][ T7293] __tsan_write4+0x32/0x40 [ 49.319937][ T7293] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.325030][ T7293] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.330563][ T7293] nf_conntrack_in+0x410/0xaa0 [ 49.335319][ T7293] ipv4_conntrack_local+0xbe/0x130 [ 49.340411][ T7293] nf_hook_slow+0x83/0x160 [ 49.344804][ T7293] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 49.349659][ T7293] __ip_local_out+0x1f7/0x2b0 [ 49.354316][ T7293] ? constant_test_bit+0x30/0x30 [ 49.359234][ T7293] ip_local_out+0x31/0x90 [ 49.363544][ T7293] __ip_queue_xmit+0x3a8/0xa40 [ 49.368287][ T7293] ip_queue_xmit+0x45/0x60 [ 49.372684][ T7293] __tcp_transmit_skb+0xdeb/0x1cd0 [ 49.377780][ T7293] __tcp_send_ack+0x246/0x300 [ 49.382441][ T7293] tcp_send_ack+0x34/0x40 [ 49.386747][ T7293] tcp_cleanup_rbuf+0x130/0x360 [ 49.391575][ T7293] tcp_recvmsg+0x633/0x1a30 [ 49.396063][ T7293] inet_recvmsg+0xbb/0x250 [ 49.400473][ T7293] ? __tsan_read8+0x2c/0x30 [ 49.404956][ T7293] ? inet_sendpage+0x100/0x100 [ 49.409697][ T7293] sock_recvmsg+0x92/0xb0 [ 49.414006][ T7293] sock_read_iter+0x15f/0x1e0 [ 49.418678][ T7293] new_sync_read+0x389/0x4f0 [ 49.423257][ T7293] __vfs_read+0xb1/0xc0 [ 49.427404][ T7293] vfs_read+0x143/0x2c0 [ 49.431541][ T7293] ksys_read+0xd5/0x1b0 [ 49.435678][ T7293] __x64_sys_read+0x4c/0x60 [ 49.440182][ T7293] do_syscall_64+0xcf/0x2f0 [ 49.444669][ T7293] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.450536][ T7293] RIP: 0033:0x47c530 [ 49.454410][ T7293] 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 [ 49.473993][ T7293] RSP: 002b:000000c4204ef7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 49.482400][ T7293] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 49.490352][ T7293] RDX: 0000000000001000 RSI: 000000c420242000 RDI: 0000000000000003 [ 49.498300][ T7293] RBP: 000000c4204ef830 R08: 0000000000000000 R09: 0000000000000000 [ 49.506250][ T7293] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 49.514199][ T7293] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 49.523419][ T7293] Kernel Offset: disabled [ 49.527761][ T7293] Rebooting in 86400 seconds..