[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.740057][ T26] audit: type=1800 audit(1572633249.037:25): pid=7029 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.775211][ T26] audit: type=1800 audit(1572633249.037:26): pid=7029 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.797364][ T26] audit: type=1800 audit(1572633249.047:27): pid=7029 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 '10.128.1.51' (ECDSA) to the list of known hosts. 2019/11/01 18:34:19 fuzzer started 2019/11/01 18:34:21 dialing manager at 10.128.0.105:41349 2019/11/01 18:34:21 syscalls: 2540 2019/11/01 18:34:21 code coverage: enabled 2019/11/01 18:34:21 comparison tracing: enabled 2019/11/01 18:34:21 extra coverage: extra coverage is not supported by the kernel 2019/11/01 18:34:21 setuid sandbox: enabled 2019/11/01 18:34:21 namespace sandbox: enabled 2019/11/01 18:34:21 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/01 18:34:21 fault injection: enabled 2019/11/01 18:34:21 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/01 18:34:21 net packet injection: enabled 2019/11/01 18:34:21 net device setup: enabled 2019/11/01 18:34:21 concurrency sanitizer: enabled 2019/11/01 18:34:23 adding functions to KCSAN blacklist: 'pid_update_inode' 'tomoyo_supervisor' 'tick_do_update_jiffies64' 'ep_poll' '__hrtimer_run_queues' 'tcp_add_backlog' 'task_dump_owner' '__nf_conntrack_find_get' 'generic_permission' 'ktime_get_real_seconds' 'common_perm_cond' 'run_timer_softirq' 'ext4_free_inode' 'pipe_poll' syzkaller login: [ 51.557915][ T7188] ================================================================== [ 51.566517][ T7188] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 51.574884][ T7188] [ 51.577195][ T7188] read to 0xffff888123845b08 of 4 bytes by interrupt on cpu 1: [ 51.584863][ T7188] __nf_ct_refresh_acct+0xd4/0x1b0 [ 51.589957][ T7188] nf_conntrack_tcp_packet+0xd40/0x3390 [ 51.595678][ T7188] nf_conntrack_in+0x410/0xa80 [ 51.600447][ T7188] ipv4_conntrack_in+0x27/0x40 [ 51.605204][ T7188] nf_hook_slow+0x83/0x160 [ 51.609614][ T7188] ip_rcv+0x12f/0x1a0 [ 51.613612][ T7188] __netif_receive_skb_one_core+0xa7/0xe0 [ 51.619306][ T7188] __netif_receive_skb+0x37/0xf0 [ 51.624233][ T7188] netif_receive_skb_internal+0x59/0x190 [ 51.629841][ T7188] napi_gro_receive+0x28f/0x330 [ 51.634790][ T7188] receive_buf+0x284/0x30b0 [ 51.639291][ T7188] virtnet_poll+0x436/0x7d0 [ 51.643881][ T7188] net_rx_action+0x3ae/0xa90 [ 51.648557][ T7188] __do_softirq+0x115/0x33f [ 51.653035][ T7188] [ 51.655346][ T7188] write to 0xffff888123845b08 of 4 bytes by task 7188 on cpu 0: [ 51.663999][ T7188] __nf_ct_refresh_acct+0xfb/0x1b0 [ 51.669105][ T7188] nf_conntrack_tcp_packet+0xd40/0x3390 [ 51.674640][ T7188] nf_conntrack_in+0x410/0xa80 [ 51.679434][ T7188] ipv4_conntrack_local+0xbe/0x130 [ 51.684639][ T7188] nf_hook_slow+0x83/0x160 [ 51.689035][ T7188] __ip_local_out+0x1f7/0x2b0 [ 51.693716][ T7188] ip_local_out+0x31/0x90 [ 51.698084][ T7188] __ip_queue_xmit+0x3a8/0xa40 [ 51.702854][ T7188] ip_queue_xmit+0x45/0x60 [ 51.707251][ T7188] __tcp_transmit_skb+0xe81/0x1d60 [ 51.712378][ T7188] __tcp_send_ack+0x246/0x300 [ 51.717036][ T7188] tcp_send_ack+0x34/0x40 [ 51.721345][ T7188] tcp_cleanup_rbuf+0x130/0x360 [ 51.726285][ T7188] [ 51.728587][ T7188] Reported by Kernel Concurrency Sanitizer on: [ 51.734721][ T7188] CPU: 0 PID: 7188 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 51.742145][ T7188] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.752174][ T7188] ================================================================== [ 51.760215][ T7188] Kernel panic - not syncing: panic_on_warn set ... [ 51.766974][ T7188] CPU: 0 PID: 7188 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 51.774694][ T7188] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.785083][ T7188] Call Trace: [ 51.788360][ T7188] dump_stack+0xf5/0x159 [ 51.792605][ T7188] panic+0x210/0x640 [ 51.796480][ T7188] ? ip_queue_xmit+0x45/0x60 [ 51.801104][ T7188] ? vprintk_func+0x8d/0x140 [ 51.805733][ T7188] kcsan_report.cold+0xc/0x10 [ 51.810398][ T7188] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 51.816009][ T7188] __tsan_write4+0x32/0x40 [ 51.820496][ T7188] __nf_ct_refresh_acct+0xfb/0x1b0 [ 51.825821][ T7188] nf_conntrack_tcp_packet+0xd40/0x3390 [ 51.831442][ T7188] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 51.837074][ T7188] nf_conntrack_in+0x410/0xa80 [ 51.841913][ T7188] ipv4_conntrack_local+0xbe/0x130 [ 51.847012][ T7188] nf_hook_slow+0x83/0x160 [ 51.851405][ T7188] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 51.856166][ T7188] __ip_local_out+0x1f7/0x2b0 [ 51.860915][ T7188] ? constant_test_bit+0x30/0x30 [ 51.865852][ T7188] ip_local_out+0x31/0x90 [ 51.870264][ T7188] __ip_queue_xmit+0x3a8/0xa40 [ 51.875125][ T7188] ip_queue_xmit+0x45/0x60 [ 51.879870][ T7188] __tcp_transmit_skb+0xe81/0x1d60 [ 51.884969][ T7188] __tcp_send_ack+0x246/0x300 [ 51.889763][ T7188] tcp_send_ack+0x34/0x40 [ 51.894093][ T7188] tcp_cleanup_rbuf+0x130/0x360 [ 51.898940][ T7188] tcp_recvmsg+0x633/0x1a30 [ 51.903431][ T7188] inet_recvmsg+0xbb/0x250 [ 51.907826][ T7188] ? __tsan_read8+0x2c/0x30 [ 51.912608][ T7188] ? inet_sendpage+0x100/0x100 [ 51.917363][ T7188] sock_recvmsg+0x92/0xb0 [ 51.921696][ T7188] sock_read_iter+0x15f/0x1e0 [ 51.926441][ T7188] new_sync_read+0x389/0x4f0 [ 51.931013][ T7188] __vfs_read+0xb1/0xc0 [ 51.935148][ T7188] vfs_read+0x143/0x2c0 [ 51.939279][ T7188] ksys_read+0xd5/0x1b0 [ 51.944109][ T7188] __x64_sys_read+0x4c/0x60 [ 51.948592][ T7188] do_syscall_64+0xcc/0x370 [ 51.953072][ T7188] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 51.958937][ T7188] RIP: 0033:0x47c530 [ 51.962821][ T7188] 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 [ 51.982408][ T7188] RSP: 002b:000000c4204fd7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 51.990867][ T7188] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 51.998833][ T7188] RDX: 0000000000001000 RSI: 000000c4203b0000 RDI: 0000000000000003 [ 52.006784][ T7188] RBP: 000000c4204fd830 R08: 0000000000000000 R09: 0000000000000000 [ 52.014736][ T7188] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 52.022687][ T7188] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 52.032485][ T7188] Kernel Offset: disabled [ 52.036934][ T7188] Rebooting in 86400 seconds..