[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.635903][ T25] audit: type=1800 audit(1571718601.128:25): pid=7042 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.663020][ T25] audit: type=1800 audit(1571718601.128:26): pid=7042 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.689659][ T25] audit: type=1800 audit(1571718601.128:27): pid=7042 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 '10.128.0.103' (ECDSA) to the list of known hosts. 2019/10/22 04:30:11 fuzzer started 2019/10/22 04:30:13 dialing manager at 10.128.0.105:37053 2019/10/22 04:30:13 syscalls: 2524 2019/10/22 04:30:13 code coverage: enabled 2019/10/22 04:30:13 comparison tracing: enabled 2019/10/22 04:30:13 extra coverage: extra coverage is not supported by the kernel 2019/10/22 04:30:13 setuid sandbox: enabled 2019/10/22 04:30:13 namespace sandbox: enabled 2019/10/22 04:30:13 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 04:30:13 fault injection: enabled 2019/10/22 04:30:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 04:30:13 net packet injection: enabled 2019/10/22 04:30:13 net device setup: enabled 2019/10/22 04:30:13 concurrency sanitizer: enabled syzkaller login: [ 47.940226][ T7190] ================================================================== [ 47.948369][ T7190] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 47.956607][ T7190] [ 47.958940][ T7190] read to 0xffff8881247cda08 of 4 bytes by interrupt on cpu 1: [ 47.966476][ T7190] __nf_ct_refresh_acct+0xd4/0x1b0 [ 47.971650][ T7190] nf_conntrack_tcp_packet+0xd40/0x3390 [ 47.977171][ T7190] nf_conntrack_in+0x410/0xa80 [ 47.981911][ T7190] ipv4_conntrack_in+0x27/0x40 [ 47.986692][ T7190] nf_hook_slow+0x83/0x160 [ 47.991085][ T7190] ip_rcv+0x12f/0x1a0 [ 47.995047][ T7190] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.000746][ T7190] __netif_receive_skb+0x37/0xf0 [ 48.005671][ T7190] netif_receive_skb_internal+0x59/0x190 [ 48.011294][ T7190] napi_gro_receive+0x28f/0x330 [ 48.016122][ T7190] receive_buf+0x284/0x30b0 [ 48.020603][ T7190] virtnet_poll+0x436/0x7d0 [ 48.025098][ T7190] net_rx_action+0x3ae/0xa90 [ 48.029666][ T7190] __do_softirq+0x115/0x33f [ 48.034141][ T7190] [ 48.036466][ T7190] write to 0xffff8881247cda08 of 4 bytes by task 7190 on cpu 0: [ 48.044075][ T7190] __nf_ct_refresh_acct+0xfb/0x1b0 [ 48.049163][ T7190] nf_conntrack_tcp_packet+0xd40/0x3390 [ 48.054685][ T7190] nf_conntrack_in+0x410/0xa80 [ 48.059422][ T7190] ipv4_conntrack_local+0xbe/0x130 [ 48.064512][ T7190] nf_hook_slow+0x83/0x160 [ 48.068917][ T7190] __ip_local_out+0x1f7/0x2b0 [ 48.073583][ T7190] ip_local_out+0x31/0x90 [ 48.077889][ T7190] __ip_queue_xmit+0x3a8/0xa40 [ 48.082631][ T7190] ip_queue_xmit+0x45/0x60 [ 48.087037][ T7190] __tcp_transmit_skb+0xe81/0x1d60 [ 48.092126][ T7190] __tcp_send_ack+0x246/0x300 [ 48.096779][ T7190] tcp_send_ack+0x34/0x40 [ 48.101089][ T7190] tcp_cleanup_rbuf+0x130/0x360 [ 48.105912][ T7190] [ 48.108214][ T7190] Reported by Kernel Concurrency Sanitizer on: [ 48.114345][ T7190] CPU: 0 PID: 7190 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.122157][ T7190] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.132213][ T7190] ================================================================== [ 48.140267][ T7190] Kernel panic - not syncing: panic_on_warn set ... [ 48.146836][ T7190] CPU: 0 PID: 7190 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.154386][ T7190] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.164418][ T7190] Call Trace: [ 48.167695][ T7190] dump_stack+0xf5/0x159 [ 48.171918][ T7190] panic+0x210/0x640 [ 48.175881][ T7190] ? ip_queue_xmit+0x45/0x60 [ 48.180456][ T7190] ? vprintk_func+0x8d/0x140 [ 48.185030][ T7190] kcsan_report.cold+0xc/0x10 [ 48.189686][ T7190] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.195212][ T7190] __tsan_write4+0x32/0x40 [ 48.199624][ T7190] __nf_ct_refresh_acct+0xfb/0x1b0 [ 48.204721][ T7190] nf_conntrack_tcp_packet+0xd40/0x3390 [ 48.210259][ T7190] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.215891][ T7190] nf_conntrack_in+0x410/0xa80 [ 48.220659][ T7190] ipv4_conntrack_local+0xbe/0x130 [ 48.225844][ T7190] nf_hook_slow+0x83/0x160 [ 48.230501][ T7190] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 48.235246][ T7190] __ip_local_out+0x1f7/0x2b0 [ 48.239904][ T7190] ? constant_test_bit+0x30/0x30 [ 48.244835][ T7190] ip_local_out+0x31/0x90 [ 48.249245][ T7190] __ip_queue_xmit+0x3a8/0xa40 [ 48.254011][ T7190] ip_queue_xmit+0x45/0x60 [ 48.258408][ T7190] __tcp_transmit_skb+0xe81/0x1d60 [ 48.263504][ T7190] __tcp_send_ack+0x246/0x300 [ 48.268162][ T7190] tcp_send_ack+0x34/0x40 [ 48.272687][ T7190] tcp_cleanup_rbuf+0x130/0x360 [ 48.277778][ T7190] tcp_recvmsg+0x633/0x1a30 [ 48.282268][ T7190] inet_recvmsg+0xbb/0x250 [ 48.286663][ T7190] ? __tsan_read8+0x2c/0x30 [ 48.291145][ T7190] ? inet_sendpage+0x100/0x100 [ 48.295888][ T7190] sock_recvmsg+0x92/0xb0 [ 48.300204][ T7190] sock_read_iter+0x15f/0x1e0 [ 48.304866][ T7190] new_sync_read+0x389/0x4f0 [ 48.309439][ T7190] __vfs_read+0xb1/0xc0 [ 48.315570][ T7190] vfs_read+0x143/0x2c0 [ 48.319702][ T7190] ksys_read+0xd5/0x1b0 [ 48.323847][ T7190] __x64_sys_read+0x4c/0x60 [ 48.328338][ T7190] do_syscall_64+0xcc/0x370 [ 48.332830][ T7190] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.338697][ T7190] RIP: 0033:0x47c530 [ 48.342658][ T7190] 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 [ 48.362237][ T7190] RSP: 002b:000000c4204f5818 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 48.370633][ T7190] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.378588][ T7190] RDX: 0000000000001000 RSI: 000000c420382000 RDI: 0000000000000003 [ 48.386536][ T7190] RBP: 000000c4204f5870 R08: 0000000000000000 R09: 0000000000000000 [ 48.394493][ T7190] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000040 [ 48.402442][ T7190] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 48.411698][ T7190] Kernel Offset: disabled [ 48.416019][ T7190] Rebooting in 86400 seconds..