[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.321624][ T26] audit: type=1800 audit(1571738013.583:25): pid=7124 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.349237][ T26] audit: type=1800 audit(1571738013.583:26): pid=7124 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.376427][ T26] audit: type=1800 audit(1571738013.583:27): pid=7124 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 '10.128.10.48' (ECDSA) to the list of known hosts. 2019/10/22 09:53:44 fuzzer started 2019/10/22 09:53:46 dialing manager at 10.128.0.105:37053 2019/10/22 09:53:46 syscalls: 2524 2019/10/22 09:53:46 code coverage: enabled 2019/10/22 09:53:46 comparison tracing: enabled 2019/10/22 09:53:46 extra coverage: extra coverage is not supported by the kernel 2019/10/22 09:53:46 setuid sandbox: enabled 2019/10/22 09:53:46 namespace sandbox: enabled 2019/10/22 09:53:46 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 09:53:46 fault injection: enabled 2019/10/22 09:53:46 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 09:53:46 net packet injection: enabled 2019/10/22 09:53:46 net device setup: enabled 2019/10/22 09:53:46 concurrency sanitizer: enabled syzkaller login: [ 49.449643][ T7276] ================================================================== [ 49.457923][ T7276] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 49.466130][ T7276] [ 49.468438][ T7276] read to 0xffff888124701208 of 4 bytes by interrupt on cpu 0: [ 49.476010][ T7276] __nf_ct_refresh_acct+0xd4/0x1b0 [ 49.481101][ T7276] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.486624][ T7276] nf_conntrack_in+0x410/0xa80 [ 49.491361][ T7276] ipv4_conntrack_in+0x27/0x40 [ 49.496102][ T7276] nf_hook_slow+0x83/0x160 [ 49.500492][ T7276] ip_rcv+0x12f/0x1a0 [ 49.504466][ T7276] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.510172][ T7276] __netif_receive_skb+0x37/0xf0 [ 49.515100][ T7276] netif_receive_skb_internal+0x59/0x190 [ 49.520708][ T7276] napi_gro_receive+0x28f/0x330 [ 49.525534][ T7276] receive_buf+0x284/0x30b0 [ 49.530014][ T7276] virtnet_poll+0x436/0x7d0 [ 49.534495][ T7276] net_rx_action+0x3ae/0xa90 [ 49.539062][ T7276] __do_softirq+0x115/0x33f [ 49.543546][ T7276] [ 49.545855][ T7276] write to 0xffff888124701208 of 4 bytes by task 7276 on cpu 1: [ 49.553462][ T7276] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.558562][ T7276] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.564094][ T7276] nf_conntrack_in+0x410/0xa80 [ 49.568834][ T7276] ipv4_conntrack_local+0xbe/0x130 [ 49.573921][ T7276] nf_hook_slow+0x83/0x160 [ 49.578313][ T7276] __ip_local_out+0x1f7/0x2b0 [ 49.582977][ T7276] ip_local_out+0x31/0x90 [ 49.587285][ T7276] __ip_queue_xmit+0x3a8/0xa40 [ 49.592023][ T7276] ip_queue_xmit+0x45/0x60 [ 49.596412][ T7276] __tcp_transmit_skb+0xe81/0x1d60 [ 49.601497][ T7276] __tcp_send_ack+0x246/0x300 [ 49.606148][ T7276] tcp_send_ack+0x34/0x40 [ 49.610455][ T7276] __tcp_ack_snd_check+0xd9/0x4f0 [ 49.615461][ T7276] [ 49.617776][ T7276] Reported by Kernel Concurrency Sanitizer on: [ 49.623913][ T7276] CPU: 1 PID: 7276 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.631354][ T7276] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.641385][ T7276] ================================================================== [ 49.649435][ T7276] Kernel panic - not syncing: panic_on_warn set ... [ 49.655998][ T7276] CPU: 1 PID: 7276 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.663426][ T7276] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.673468][ T7276] Call Trace: [ 49.676744][ T7276] dump_stack+0xf5/0x159 [ 49.680966][ T7276] panic+0x210/0x640 [ 49.684839][ T7276] ? ip_queue_xmit+0x45/0x60 [ 49.689408][ T7276] ? vprintk_func+0x8d/0x140 [ 49.693980][ T7276] kcsan_report.cold+0xc/0x10 [ 49.698635][ T7276] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.704160][ T7276] ? pfifo_fast_dequeue+0x3d1/0x6e0 [ 49.709352][ T7276] __tsan_write4+0x32/0x40 [ 49.713747][ T7276] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.718855][ T7276] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.724406][ T7276] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.730038][ T7276] nf_conntrack_in+0x410/0xa80 [ 49.734805][ T7276] ipv4_conntrack_local+0xbe/0x130 [ 49.739901][ T7276] nf_hook_slow+0x83/0x160 [ 49.744309][ T7276] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 49.749086][ T7276] __ip_local_out+0x1f7/0x2b0 [ 49.753745][ T7276] ? constant_test_bit+0x30/0x30 [ 49.758849][ T7276] ip_local_out+0x31/0x90 [ 49.763173][ T7276] __ip_queue_xmit+0x3a8/0xa40 [ 49.767920][ T7276] ip_queue_xmit+0x45/0x60 [ 49.772327][ T7276] __tcp_transmit_skb+0xe81/0x1d60 [ 49.777421][ T7276] __tcp_send_ack+0x246/0x300 [ 49.782251][ T7276] tcp_send_ack+0x34/0x40 [ 49.786560][ T7276] __tcp_ack_snd_check+0xd9/0x4f0 [ 49.791565][ T7276] tcp_rcv_established+0xce9/0xf50 [ 49.796667][ T7276] ? ipv4_dst_check+0xc6/0xf0 [ 49.801322][ T7276] tcp_v4_do_rcv+0x381/0x4e0 [ 49.805905][ T7276] __release_sock+0x135/0x1e0 [ 49.810588][ T7276] release_sock+0x61/0x160 [ 49.814986][ T7276] tcp_recvmsg+0x63b/0x1a30 [ 49.819580][ T7276] inet_recvmsg+0xbb/0x250 [ 49.823988][ T7276] ? __tsan_read8+0x2c/0x30 [ 49.828496][ T7276] ? inet_sendpage+0x100/0x100 [ 49.833239][ T7276] sock_recvmsg+0x92/0xb0 [ 49.837552][ T7276] sock_read_iter+0x15f/0x1e0 [ 49.842213][ T7276] new_sync_read+0x389/0x4f0 [ 49.846785][ T7276] __vfs_read+0xb1/0xc0 [ 49.850922][ T7276] vfs_read+0x143/0x2c0 [ 49.855071][ T7276] ksys_read+0xd5/0x1b0 [ 49.859207][ T7276] __x64_sys_read+0x4c/0x60 [ 49.863692][ T7276] do_syscall_64+0xcc/0x370 [ 49.868193][ T7276] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.874061][ T7276] RIP: 0033:0x47c530 [ 49.877956][ T7276] 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 [ 49.897554][ T7276] RSP: 002b:000000c4204ff7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 49.905942][ T7276] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 49.913910][ T7276] RDX: 0000000000001000 RSI: 000000c420134000 RDI: 0000000000000003 [ 49.921863][ T7276] RBP: 000000c4204ff830 R08: 0000000000000000 R09: 0000000000000000 [ 49.929984][ T7276] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 49.938073][ T7276] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 49.947559][ T7276] Kernel Offset: disabled [ 49.951981][ T7276] Rebooting in 86400 seconds..