[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.914535][ T25] audit: type=1800 audit(1572869312.700:25): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.969577][ T25] audit: type=1800 audit(1572869312.700:26): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.997953][ T25] audit: type=1800 audit(1572869312.700:27): pid=7026 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 '10.128.15.197' (ECDSA) to the list of known hosts. 2019/11/04 12:08:43 fuzzer started 2019/11/04 12:08:45 dialing manager at 10.128.0.105:43623 2019/11/04 12:08:45 syscalls: 2553 2019/11/04 12:08:45 code coverage: enabled 2019/11/04 12:08:45 comparison tracing: enabled 2019/11/04 12:08:45 extra coverage: extra coverage is not supported by the kernel 2019/11/04 12:08:45 setuid sandbox: enabled 2019/11/04 12:08:45 namespace sandbox: enabled 2019/11/04 12:08:45 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/04 12:08:45 fault injection: enabled 2019/11/04 12:08:45 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/04 12:08:45 net packet injection: enabled 2019/11/04 12:08:45 net device setup: enabled 2019/11/04 12:08:45 concurrency sanitizer: enabled 2019/11/04 12:08:45 devlink PCI setup: PCI device 0000:00:10.0 is not available 2019/11/04 12:08:49 adding functions to KCSAN blacklist: '__tcp_select_window' 'tcp_poll' '__nf_conntrack_find_get' 'tomoyo_supervisor' 'ext4_has_free_clusters' 'pid_update_inode' 'tcp_add_backlog' '__hrtimer_run_queues' 'find_next_bit' 'ep_poll' 'ktime_get_real_seconds' 'taskstats_exit' 'pipe_poll' 'generic_fillattr' 'add_timer' 'generic_permission' syzkaller login: [ 52.434616][ T7180] ================================================================== [ 52.442748][ T7180] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 52.450968][ T7180] [ 52.453289][ T7180] read to 0xffff888123f78b08 of 4 bytes by interrupt on cpu 1: [ 52.460867][ T7180] __nf_ct_refresh_acct+0xd4/0x1b0 [ 52.465958][ T7180] nf_conntrack_tcp_packet+0xd40/0x3390 [ 52.471486][ T7180] nf_conntrack_in+0x410/0xa80 [ 52.476225][ T7180] ipv4_conntrack_in+0x27/0x40 [ 52.480968][ T7180] nf_hook_slow+0x83/0x160 [ 52.485397][ T7180] ip_rcv+0x12f/0x1a0 [ 52.489357][ T7180] __netif_receive_skb_one_core+0xa7/0xe0 [ 52.495050][ T7180] __netif_receive_skb+0x37/0xf0 [ 52.499973][ T7180] netif_receive_skb_internal+0x59/0x190 [ 52.505584][ T7180] napi_gro_receive+0x28f/0x330 [ 52.510409][ T7180] receive_buf+0x284/0x30b0 [ 52.514886][ T7180] virtnet_poll+0x436/0x7d0 [ 52.519397][ T7180] net_rx_action+0x3ae/0xa90 [ 52.524006][ T7180] __do_softirq+0x115/0x33f [ 52.528514][ T7180] [ 52.530829][ T7180] write to 0xffff888123f78b08 of 4 bytes by task 7180 on cpu 0: [ 52.538433][ T7180] __nf_ct_refresh_acct+0xfb/0x1b0 [ 52.543519][ T7180] nf_conntrack_tcp_packet+0xd40/0x3390 [ 52.549038][ T7180] nf_conntrack_in+0x410/0xa80 [ 52.553799][ T7180] ipv4_conntrack_local+0xbe/0x130 [ 52.558899][ T7180] nf_hook_slow+0x83/0x160 [ 52.563316][ T7180] __ip_local_out+0x1f7/0x2b0 [ 52.567970][ T7180] ip_local_out+0x31/0x90 [ 52.572286][ T7180] __ip_queue_xmit+0x3a8/0xa40 [ 52.578882][ T7180] ip_queue_xmit+0x45/0x60 [ 52.583294][ T7180] __tcp_transmit_skb+0xe81/0x1d60 [ 52.588378][ T7180] __tcp_send_ack+0x246/0x300 [ 52.593031][ T7180] tcp_send_ack+0x34/0x40 [ 52.597345][ T7180] tcp_cleanup_rbuf+0x130/0x360 [ 52.602171][ T7180] [ 52.604483][ T7180] Reported by Kernel Concurrency Sanitizer on: [ 52.610623][ T7180] CPU: 0 PID: 7180 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 52.618058][ T7180] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.628096][ T7180] ================================================================== [ 52.636128][ T7180] Kernel panic - not syncing: panic_on_warn set ... [ 52.642701][ T7180] CPU: 0 PID: 7180 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 52.650139][ T7180] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.660179][ T7180] Call Trace: [ 52.663449][ T7180] dump_stack+0xf5/0x159 [ 52.667679][ T7180] panic+0x210/0x640 [ 52.671551][ T7180] ? ip_queue_xmit+0x45/0x60 [ 52.676113][ T7180] ? vprintk_func+0x8d/0x140 [ 52.680680][ T7180] kcsan_report.cold+0xc/0x10 [ 52.685336][ T7180] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 52.690875][ T7180] __tsan_write4+0x32/0x40 [ 52.695283][ T7180] __nf_ct_refresh_acct+0xfb/0x1b0 [ 52.700371][ T7180] nf_conntrack_tcp_packet+0xd40/0x3390 [ 52.705905][ T7180] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 52.711513][ T7180] nf_conntrack_in+0x410/0xa80 [ 52.716256][ T7180] ipv4_conntrack_local+0xbe/0x130 [ 52.721345][ T7180] nf_hook_slow+0x83/0x160 [ 52.725736][ T7180] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 52.730474][ T7180] __ip_local_out+0x1f7/0x2b0 [ 52.735127][ T7180] ? constant_test_bit+0x30/0x30 [ 52.740040][ T7180] ip_local_out+0x31/0x90 [ 52.744354][ T7180] __ip_queue_xmit+0x3a8/0xa40 [ 52.749101][ T7180] ip_queue_xmit+0x45/0x60 [ 52.753494][ T7180] __tcp_transmit_skb+0xe81/0x1d60 [ 52.758587][ T7180] __tcp_send_ack+0x246/0x300 [ 52.763241][ T7180] tcp_send_ack+0x34/0x40 [ 52.767549][ T7180] tcp_cleanup_rbuf+0x130/0x360 [ 52.772386][ T7180] tcp_recvmsg+0x633/0x1a30 [ 52.776873][ T7180] inet_recvmsg+0xbb/0x250 [ 52.781274][ T7180] ? __tsan_read8+0x2c/0x30 [ 52.785756][ T7180] ? inet_sendpage+0x100/0x100 [ 52.790523][ T7180] sock_recvmsg+0x92/0xb0 [ 52.794831][ T7180] sock_read_iter+0x15f/0x1e0 [ 52.799489][ T7180] new_sync_read+0x389/0x4f0 [ 52.804060][ T7180] __vfs_read+0xb1/0xc0 [ 52.808191][ T7180] vfs_read+0x143/0x2c0 [ 52.812335][ T7180] ksys_read+0xd5/0x1b0 [ 52.822554][ T7180] __x64_sys_read+0x4c/0x60 [ 52.827139][ T7180] do_syscall_64+0xcc/0x370 [ 52.831630][ T7180] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.837493][ T7180] RIP: 0033:0x47c530 [ 52.841379][ T7180] 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 [ 52.860956][ T7180] RSP: 002b:000000c4200517d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 52.869341][ T7180] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 52.877290][ T7180] RDX: 0000000000001000 RSI: 000000c420378000 RDI: 0000000000000003 [ 52.885238][ T7180] RBP: 000000c420051830 R08: 0000000000000000 R09: 0000000000000000 [ 52.893183][ T7180] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000002 [ 52.901129][ T7180] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 52.910508][ T7180] Kernel Offset: disabled [ 52.914830][ T7180] Rebooting in 86400 seconds..