[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.269665][ T25] audit: type=1800 audit(1571757758.136:25): pid=7098 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.319711][ T25] audit: type=1800 audit(1571757758.146:26): pid=7098 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.342612][ T25] audit: type=1800 audit(1571757758.146:27): pid=7098 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 '10.128.0.60' (ECDSA) to the list of known hosts. 2019/10/22 15:22:48 fuzzer started 2019/10/22 15:22:49 dialing manager at 10.128.0.105:33369 2019/10/22 15:22:49 syscalls: 2524 2019/10/22 15:22:49 code coverage: enabled 2019/10/22 15:22:49 comparison tracing: enabled 2019/10/22 15:22:49 extra coverage: extra coverage is not supported by the kernel 2019/10/22 15:22:49 setuid sandbox: enabled 2019/10/22 15:22:49 namespace sandbox: enabled 2019/10/22 15:22:49 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 15:22:49 fault injection: enabled 2019/10/22 15:22:49 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 15:22:49 net packet injection: enabled 2019/10/22 15:22:49 net device setup: enabled 2019/10/22 15:22:49 concurrency sanitizer: enabled syzkaller login: [ 45.593744][ T7266] ================================================================== [ 45.601895][ T7266] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 45.610110][ T7266] [ 45.612427][ T7266] read to 0xffff888123f76408 of 4 bytes by interrupt on cpu 1: [ 45.619965][ T7266] __nf_ct_refresh_acct+0xd4/0x1b0 [ 45.625223][ T7266] nf_conntrack_tcp_packet+0xd40/0x3390 [ 45.631456][ T7266] nf_conntrack_in+0x410/0xa80 [ 45.636285][ T7266] ipv4_conntrack_in+0x27/0x40 [ 45.641078][ T7266] nf_hook_slow+0x83/0x160 [ 45.645523][ T7266] ip_rcv+0x12f/0x1a0 [ 45.649484][ T7266] __netif_receive_skb_one_core+0xa7/0xe0 [ 45.655182][ T7266] __netif_receive_skb+0x37/0xf0 [ 45.660190][ T7266] netif_receive_skb_internal+0x59/0x190 [ 45.665814][ T7266] napi_gro_receive+0x28f/0x330 [ 45.670657][ T7266] receive_buf+0x284/0x30b0 [ 45.675164][ T7266] virtnet_poll+0x436/0x7d0 [ 45.679661][ T7266] net_rx_action+0x3ae/0xa90 [ 45.684245][ T7266] __do_softirq+0x115/0x33f [ 45.688717][ T7266] [ 45.691041][ T7266] write to 0xffff888123f76408 of 4 bytes by task 7266 on cpu 0: [ 45.698648][ T7266] __nf_ct_refresh_acct+0xfb/0x1b0 [ 45.703750][ T7266] nf_conntrack_tcp_packet+0xd40/0x3390 [ 45.709296][ T7266] nf_conntrack_in+0x410/0xa80 [ 45.714042][ T7266] ipv4_conntrack_local+0xbe/0x130 [ 45.719144][ T7266] nf_hook_slow+0x83/0x160 [ 45.723538][ T7266] __ip_local_out+0x1f7/0x2b0 [ 45.728196][ T7266] ip_local_out+0x31/0x90 [ 45.732503][ T7266] __ip_queue_xmit+0x3a8/0xa40 [ 45.737251][ T7266] ip_queue_xmit+0x45/0x60 [ 45.741667][ T7266] __tcp_transmit_skb+0xe81/0x1d60 [ 45.746752][ T7266] __tcp_send_ack+0x246/0x300 [ 45.751420][ T7266] tcp_send_ack+0x34/0x40 [ 45.755730][ T7266] tcp_cleanup_rbuf+0x130/0x360 [ 45.760549][ T7266] [ 45.762860][ T7266] Reported by Kernel Concurrency Sanitizer on: [ 45.768995][ T7266] CPU: 0 PID: 7266 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.776425][ T7266] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.786545][ T7266] ================================================================== [ 45.794581][ T7266] Kernel panic - not syncing: panic_on_warn set ... [ 45.801147][ T7266] CPU: 0 PID: 7266 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.808585][ T7266] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.818766][ T7266] Call Trace: [ 45.822058][ T7266] dump_stack+0xf5/0x159 [ 45.826286][ T7266] panic+0x210/0x640 [ 45.830178][ T7266] ? ip_queue_xmit+0x45/0x60 [ 45.834757][ T7266] ? vprintk_func+0x8d/0x140 [ 45.839328][ T7266] kcsan_report.cold+0xc/0x10 [ 45.844006][ T7266] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 45.849542][ T7266] __tsan_write4+0x32/0x40 [ 45.853957][ T7266] __nf_ct_refresh_acct+0xfb/0x1b0 [ 45.859106][ T7266] nf_conntrack_tcp_packet+0xd40/0x3390 [ 45.864774][ T7266] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 45.870393][ T7266] nf_conntrack_in+0x410/0xa80 [ 45.875140][ T7266] ipv4_conntrack_local+0xbe/0x130 [ 45.880247][ T7266] nf_hook_slow+0x83/0x160 [ 45.884653][ T7266] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 45.889418][ T7266] __ip_local_out+0x1f7/0x2b0 [ 45.894075][ T7266] ? constant_test_bit+0x30/0x30 [ 45.899008][ T7266] ip_local_out+0x31/0x90 [ 45.903333][ T7266] __ip_queue_xmit+0x3a8/0xa40 [ 45.908084][ T7266] ip_queue_xmit+0x45/0x60 [ 45.912718][ T7266] __tcp_transmit_skb+0xe81/0x1d60 [ 45.917823][ T7266] __tcp_send_ack+0x246/0x300 [ 45.922481][ T7266] tcp_send_ack+0x34/0x40 [ 45.926792][ T7266] tcp_cleanup_rbuf+0x130/0x360 [ 45.931624][ T7266] tcp_recvmsg+0x633/0x1a30 [ 45.936161][ T7266] inet_recvmsg+0xbb/0x250 [ 45.940576][ T7266] ? __tsan_read8+0x2c/0x30 [ 45.946799][ T7266] ? inet_sendpage+0x100/0x100 [ 45.951558][ T7266] sock_recvmsg+0x92/0xb0 [ 45.955869][ T7266] sock_read_iter+0x15f/0x1e0 [ 45.960537][ T7266] new_sync_read+0x389/0x4f0 [ 45.965112][ T7266] __vfs_read+0xb1/0xc0 [ 45.969259][ T7266] vfs_read+0x143/0x2c0 [ 45.973409][ T7266] ksys_read+0xd5/0x1b0 [ 45.977579][ T7266] __x64_sys_read+0x4c/0x60 [ 45.982117][ T7266] do_syscall_64+0xcc/0x370 [ 45.986648][ T7266] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.992519][ T7266] RIP: 0033:0x47c530 [ 45.996396][ T7266] 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 [ 46.015989][ T7266] RSP: 002b:000000c4203e57d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 46.024402][ T7266] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.032357][ T7266] RDX: 0000000000001000 RSI: 000000c420166000 RDI: 0000000000000003 [ 46.040322][ T7266] RBP: 000000c4203e5830 R08: 0000000000000000 R09: 0000000000000000 [ 46.048272][ T7266] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000004 [ 46.056237][ T7266] R13: ffffffffffffffff R14: 0000000000000010 R15: ffffffffffffffff [ 46.065568][ T7266] Kernel Offset: disabled [ 46.069905][ T7266] Rebooting in 86400 seconds..