[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.945349][ T26] audit: type=1800 audit(1571666354.510:25): pid=7053 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.999107][ T26] audit: type=1800 audit(1571666354.510:26): pid=7053 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.028182][ T26] audit: type=1800 audit(1571666354.510:27): pid=7053 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 '10.128.0.184' (ECDSA) to the list of known hosts. 2019/10/21 13:59:22 fuzzer started 2019/10/21 13:59:24 dialing manager at 10.128.0.105:39747 2019/10/21 13:59:24 syscalls: 2524 2019/10/21 13:59:24 code coverage: enabled 2019/10/21 13:59:24 comparison tracing: enabled 2019/10/21 13:59:24 extra coverage: extra coverage is not supported by the kernel 2019/10/21 13:59:24 setuid sandbox: enabled 2019/10/21 13:59:24 namespace sandbox: enabled 2019/10/21 13:59:24 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/21 13:59:24 fault injection: enabled 2019/10/21 13:59:24 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/21 13:59:24 net packet injection: enabled 2019/10/21 13:59:24 net device setup: enabled 2019/10/21 13:59:24 concurrency sanitizer: enabled syzkaller login: [ 44.542958][ T7201] ================================================================== [ 44.551094][ T7201] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 44.559304][ T7201] [ 44.561618][ T7201] read to 0xffff888126654808 of 4 bytes by interrupt on cpu 0: [ 44.569155][ T7201] __nf_ct_refresh_acct+0xd4/0x1b0 [ 44.574256][ T7201] nf_conntrack_tcp_packet+0xd40/0x3390 [ 44.579787][ T7201] nf_conntrack_in+0x410/0xa80 [ 44.584525][ T7201] ipv4_conntrack_in+0x27/0x40 [ 44.589264][ T7201] nf_hook_slow+0x83/0x160 [ 44.593652][ T7201] ip_rcv+0x12f/0x1a0 [ 44.597610][ T7201] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.603305][ T7201] __netif_receive_skb+0x37/0xf0 [ 44.608236][ T7201] netif_receive_skb_internal+0x59/0x190 [ 44.613845][ T7201] napi_gro_receive+0x28f/0x330 [ 44.618677][ T7201] receive_buf+0x284/0x30b0 [ 44.623166][ T7201] virtnet_poll+0x436/0x7d0 [ 44.627656][ T7201] net_rx_action+0x3ae/0xa90 [ 44.632224][ T7201] __do_softirq+0x115/0x33f [ 44.636696][ T7201] [ 44.639002][ T7201] write to 0xffff888126654808 of 4 bytes by task 7201 on cpu 1: [ 44.646608][ T7201] __nf_ct_refresh_acct+0xfb/0x1b0 [ 44.651714][ T7201] nf_conntrack_tcp_packet+0xd40/0x3390 [ 44.657245][ T7201] nf_conntrack_in+0x410/0xa80 [ 44.661995][ T7201] ipv4_conntrack_local+0xbe/0x130 [ 44.667080][ T7201] nf_hook_slow+0x83/0x160 [ 44.671469][ T7201] __ip_local_out+0x1f7/0x2b0 [ 44.676119][ T7201] ip_local_out+0x31/0x90 [ 44.680424][ T7201] __ip_queue_xmit+0x3a8/0xa40 [ 44.685166][ T7201] ip_queue_xmit+0x45/0x60 [ 44.689559][ T7201] __tcp_transmit_skb+0xe81/0x1d60 [ 44.694644][ T7201] __tcp_send_ack+0x246/0x300 [ 44.699306][ T7201] tcp_send_ack+0x34/0x40 [ 44.703615][ T7201] tcp_cleanup_rbuf+0x130/0x360 [ 44.708435][ T7201] [ 44.710741][ T7201] Reported by Kernel Concurrency Sanitizer on: [ 44.716881][ T7201] CPU: 1 PID: 7201 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.724311][ T7201] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.734339][ T7201] ================================================================== [ 44.742387][ T7201] Kernel panic - not syncing: panic_on_warn set ... [ 44.748969][ T7201] CPU: 1 PID: 7201 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.756397][ T7201] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.766430][ T7201] Call Trace: [ 44.769709][ T7201] dump_stack+0xf5/0x159 [ 44.773938][ T7201] panic+0x210/0x640 [ 44.777813][ T7201] ? ip_queue_xmit+0x45/0x60 [ 44.782378][ T7201] ? vprintk_func+0x8d/0x140 [ 44.786948][ T7201] kcsan_report.cold+0xc/0x10 [ 44.791603][ T7201] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 44.797127][ T7201] __tsan_write4+0x32/0x40 [ 44.801531][ T7201] __nf_ct_refresh_acct+0xfb/0x1b0 [ 44.806618][ T7201] nf_conntrack_tcp_packet+0xd40/0x3390 [ 44.812147][ T7201] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 44.817766][ T7201] nf_conntrack_in+0x410/0xa80 [ 44.822511][ T7201] ipv4_conntrack_local+0xbe/0x130 [ 44.827610][ T7201] nf_hook_slow+0x83/0x160 [ 44.832007][ T7201] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 44.836753][ T7201] __ip_local_out+0x1f7/0x2b0 [ 44.841440][ T7201] ? constant_test_bit+0x30/0x30 [ 44.846375][ T7201] ip_local_out+0x31/0x90 [ 44.850686][ T7201] __ip_queue_xmit+0x3a8/0xa40 [ 44.855433][ T7201] ip_queue_xmit+0x45/0x60 [ 44.859827][ T7201] __tcp_transmit_skb+0xe81/0x1d60 [ 44.864927][ T7201] __tcp_send_ack+0x246/0x300 [ 44.869578][ T7201] tcp_send_ack+0x34/0x40 [ 44.873888][ T7201] tcp_cleanup_rbuf+0x130/0x360 [ 44.878722][ T7201] tcp_recvmsg+0x633/0x1a30 [ 44.883211][ T7201] inet_recvmsg+0xbb/0x250 [ 44.887604][ T7201] ? __tsan_read8+0x2c/0x30 [ 44.892083][ T7201] ? inet_sendpage+0x100/0x100 [ 44.896822][ T7201] sock_recvmsg+0x92/0xb0 [ 44.901133][ T7201] sock_read_iter+0x15f/0x1e0 [ 44.905789][ T7201] new_sync_read+0x389/0x4f0 [ 44.910358][ T7201] __vfs_read+0xb1/0xc0 [ 44.914501][ T7201] vfs_read+0x143/0x2c0 [ 44.918632][ T7201] ksys_read+0xd5/0x1b0 [ 44.922765][ T7201] __x64_sys_read+0x4c/0x60 [ 44.927247][ T7201] do_syscall_64+0xcc/0x370 [ 44.931740][ T7201] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.937604][ T7201] RIP: 0033:0x47c530 [ 44.941489][ T7201] 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 [ 44.961075][ T7201] RSP: 002b:000000c4203957d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 44.969557][ T7201] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.977515][ T7201] RDX: 0000000000001000 RSI: 000000c4203f6000 RDI: 0000000000000003 [ 44.985461][ T7201] RBP: 000000c420395828 R08: 0000000000000000 R09: 0000000000000000 [ 44.993425][ T7201] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000040 [ 45.001372][ T7201] R13: ffffffffffffffff R14: 0000000000000008 R15: ffffffffffffffff [ 45.010510][ T7201] Kernel Offset: disabled [ 45.014825][ T7201] Rebooting in 86400 seconds..