[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.875416][ T25] audit: type=1800 audit(1570191471.946:25): pid=7066 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.902608][ T25] audit: type=1800 audit(1570191471.946:26): pid=7066 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.929502][ T25] audit: type=1800 audit(1570191471.946:27): pid=7066 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 12:18:03 fuzzer started 2019/10/04 12:18:04 dialing manager at 10.128.0.105:38119 2019/10/04 12:18:04 syscalls: 2523 2019/10/04 12:18:04 code coverage: enabled 2019/10/04 12:18:04 comparison tracing: enabled 2019/10/04 12:18:04 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:18:04 setuid sandbox: enabled 2019/10/04 12:18:04 namespace sandbox: enabled 2019/10/04 12:18:04 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:18:04 fault injection: enabled 2019/10/04 12:18:04 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:18:04 net packet injection: enabled 2019/10/04 12:18:04 net device setup: enabled 2019/10/04 12:18:04 concurrency sanitizer: enabled syzkaller login: [ 47.845653][ T7214] ================================================================== [ 47.853831][ T7214] BUG: KCSAN: data-race in __nf_conntrack_find_get+0x284/0x870 and __nf_ct_refresh_acct+0xfb/0x1b0 [ 47.864517][ T7214] [ 47.866827][ T7214] read to 0xffff8881233de508 of 4 bytes by interrupt on cpu 0: [ 47.874361][ T7214] __nf_conntrack_find_get+0x284/0x870 [ 47.879800][ T7214] nf_conntrack_in+0x2ef/0xaa0 [ 47.884583][ T7214] ipv4_conntrack_in+0x27/0x40 [ 47.889327][ T7214] nf_hook_slow+0x83/0x160 [ 47.893762][ T7214] ip_rcv+0x12f/0x1a0 [ 47.897722][ T7214] __netif_receive_skb_one_core+0xa7/0xe0 [ 47.903522][ T7214] __netif_receive_skb+0x37/0xf0 [ 47.908468][ T7214] netif_receive_skb_internal+0x59/0x190 [ 47.914088][ T7214] napi_gro_receive+0x28f/0x330 [ 47.918928][ T7214] receive_buf+0x284/0x30b0 [ 47.923407][ T7214] virtnet_poll+0x436/0x7d0 [ 47.927881][ T7214] net_rx_action+0x3ae/0xa50 [ 47.932459][ T7214] __do_softirq+0x115/0x33f [ 47.936953][ T7214] run_ksoftirqd+0x46/0x60 [ 47.941344][ T7214] [ 47.943681][ T7214] write to 0xffff8881233de508 of 4 bytes by task 7214 on cpu 1: [ 47.951304][ T7214] __nf_ct_refresh_acct+0xfb/0x1b0 [ 47.956393][ T7214] nf_conntrack_tcp_packet+0xd40/0x3390 [ 47.961916][ T7214] nf_conntrack_in+0x410/0xaa0 [ 47.966663][ T7214] ipv4_conntrack_local+0xbe/0x130 [ 47.971753][ T7214] nf_hook_slow+0x83/0x160 [ 47.976147][ T7214] __ip_local_out+0x1f7/0x2b0 [ 47.980799][ T7214] ip_local_out+0x31/0x90 [ 47.985103][ T7214] __ip_queue_xmit+0x3a8/0xa40 [ 47.989845][ T7214] ip_queue_xmit+0x45/0x60 [ 47.994279][ T7214] __tcp_transmit_skb+0xdeb/0x1cd0 [ 47.999386][ T7214] __tcp_send_ack+0x246/0x300 [ 48.005005][ T7214] tcp_send_ack+0x34/0x40 [ 48.009313][ T7214] tcp_cleanup_rbuf+0x130/0x360 [ 48.014131][ T7214] [ 48.016456][ T7214] Reported by Kernel Concurrency Sanitizer on: [ 48.022685][ T7214] CPU: 1 PID: 7214 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.029775][ T7214] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.039814][ T7214] ================================================================== [ 48.047855][ T7214] Kernel panic - not syncing: panic_on_warn set ... [ 48.054422][ T7214] CPU: 1 PID: 7214 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.061505][ T7214] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.071549][ T7214] Call Trace: [ 48.074849][ T7214] dump_stack+0xf5/0x159 [ 48.079070][ T7214] panic+0x209/0x639 [ 48.082957][ T7214] ? vprintk_func+0x8d/0x140 [ 48.087527][ T7214] kcsan_report.cold+0x57/0xeb [ 48.092369][ T7214] __kcsan_setup_watchpoint+0x342/0x500 [ 48.097891][ T7214] __tsan_write4+0x32/0x40 [ 48.102554][ T7214] __nf_ct_refresh_acct+0xfb/0x1b0 [ 48.107644][ T7214] nf_conntrack_tcp_packet+0xd40/0x3390 [ 48.113178][ T7214] nf_conntrack_in+0x410/0xaa0 [ 48.117933][ T7214] ipv4_conntrack_local+0xbe/0x130 [ 48.123023][ T7214] nf_hook_slow+0x83/0x160 [ 48.127440][ T7214] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 48.132190][ T7214] __ip_local_out+0x1f7/0x2b0 [ 48.136855][ T7214] ? constant_test_bit+0x30/0x30 [ 48.141805][ T7214] ip_local_out+0x31/0x90 [ 48.146120][ T7214] __ip_queue_xmit+0x3a8/0xa40 [ 48.150877][ T7214] ip_queue_xmit+0x45/0x60 [ 48.155289][ T7214] __tcp_transmit_skb+0xdeb/0x1cd0 [ 48.160385][ T7214] __tcp_send_ack+0x246/0x300 [ 48.165054][ T7214] tcp_send_ack+0x34/0x40 [ 48.169361][ T7214] tcp_cleanup_rbuf+0x130/0x360 [ 48.174189][ T7214] tcp_recvmsg+0x633/0x1a30 [ 48.178677][ T7214] inet_recvmsg+0xbb/0x250 [ 48.183174][ T7214] ? __tsan_read8+0x2c/0x30 [ 48.187724][ T7214] ? inet_sendpage+0x100/0x100 [ 48.192474][ T7214] sock_recvmsg+0x92/0xb0 [ 48.196835][ T7214] sock_read_iter+0x15f/0x1e0 [ 48.201633][ T7214] new_sync_read+0x389/0x4f0 [ 48.206216][ T7214] __vfs_read+0xb1/0xc0 [ 48.210356][ T7214] vfs_read+0x143/0x2c0 [ 48.214491][ T7214] ksys_read+0xd5/0x1b0 [ 48.218640][ T7214] __x64_sys_read+0x4c/0x60 [ 48.223124][ T7214] do_syscall_64+0xcf/0x2f0 [ 48.227611][ T7214] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.233488][ T7214] RIP: 0033:0x47c530 [ 48.237367][ T7214] 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 [ 48.257556][ T7214] RSP: 002b:000000c4204e7810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 48.265944][ T7214] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.273900][ T7214] RDX: 0000000000001000 RSI: 000000c42031e000 RDI: 0000000000000003 [ 48.281849][ T7214] RBP: 000000c4204e7868 R08: 0000000000000000 R09: 0000000000000000 [ 48.289910][ T7214] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000200 [ 48.297880][ T7214] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 48.307157][ T7214] Kernel Offset: disabled [ 48.311480][ T7214] Rebooting in 86400 seconds..