[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.606108][ T25] audit: type=1800 audit(1571775279.048:25): pid=6995 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.657416][ T25] audit: type=1800 audit(1571775279.048:26): pid=6995 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.680048][ T25] audit: type=1800 audit(1571775279.048:27): pid=6995 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 '10.128.15.204' (ECDSA) to the list of known hosts. 2019/10/22 20:14:50 fuzzer started 2019/10/22 20:14:51 dialing manager at 10.128.0.105:33369 2019/10/22 20:14:51 syscalls: 2524 2019/10/22 20:14:51 code coverage: enabled 2019/10/22 20:14:51 comparison tracing: enabled 2019/10/22 20:14:51 extra coverage: extra coverage is not supported by the kernel 2019/10/22 20:14:51 setuid sandbox: enabled 2019/10/22 20:14:51 namespace sandbox: enabled 2019/10/22 20:14:51 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 20:14:51 fault injection: enabled 2019/10/22 20:14:51 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 20:14:51 net packet injection: enabled 2019/10/22 20:14:51 net device setup: enabled 2019/10/22 20:14:51 concurrency sanitizer: enabled syzkaller login: [ 49.700762][ T7156] ================================================================== [ 49.708921][ T7156] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 49.717143][ T7156] [ 49.719465][ T7156] read to 0xffff888120640708 of 4 bytes by interrupt on cpu 0: [ 49.726988][ T7156] __nf_ct_refresh_acct+0xd4/0x1b0 [ 49.732122][ T7156] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.737650][ T7156] nf_conntrack_in+0x410/0xa80 [ 49.742392][ T7156] ipv4_conntrack_in+0x27/0x40 [ 49.747144][ T7156] nf_hook_slow+0x83/0x160 [ 49.751538][ T7156] ip_rcv+0x12f/0x1a0 [ 49.755533][ T7156] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.761228][ T7156] __netif_receive_skb+0x37/0xf0 [ 49.766213][ T7156] netif_receive_skb_internal+0x59/0x190 [ 49.771820][ T7156] napi_gro_receive+0x28f/0x330 [ 49.776645][ T7156] receive_buf+0x284/0x30b0 [ 49.781138][ T7156] virtnet_poll+0x436/0x7d0 [ 49.785619][ T7156] net_rx_action+0x3ae/0xa90 [ 49.790308][ T7156] __do_softirq+0x115/0x33f [ 49.794781][ T7156] [ 49.797092][ T7156] write to 0xffff888120640708 of 4 bytes by task 7156 on cpu 1: [ 49.804708][ T7156] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.809794][ T7156] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.815315][ T7156] nf_conntrack_in+0x410/0xa80 [ 49.820067][ T7156] ipv4_conntrack_local+0xbe/0x130 [ 49.825159][ T7156] nf_hook_slow+0x83/0x160 [ 49.829552][ T7156] __ip_local_out+0x1f7/0x2b0 [ 49.834203][ T7156] ip_local_out+0x31/0x90 [ 49.838506][ T7156] __ip_queue_xmit+0x3a8/0xa40 [ 49.843264][ T7156] ip_queue_xmit+0x45/0x60 [ 49.847656][ T7156] __tcp_transmit_skb+0xe81/0x1d60 [ 49.852745][ T7156] __tcp_send_ack+0x246/0x300 [ 49.857398][ T7156] tcp_send_ack+0x34/0x40 [ 49.861703][ T7156] tcp_cleanup_rbuf+0x130/0x360 [ 49.866535][ T7156] [ 49.868836][ T7156] Reported by Kernel Concurrency Sanitizer on: [ 49.874979][ T7156] CPU: 1 PID: 7156 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.882421][ T7156] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.892451][ T7156] ================================================================== [ 49.900486][ T7156] Kernel panic - not syncing: panic_on_warn set ... [ 49.907076][ T7156] CPU: 1 PID: 7156 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.914505][ T7156] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.924534][ T7156] Call Trace: [ 49.927984][ T7156] dump_stack+0xf5/0x159 [ 49.932203][ T7156] panic+0x210/0x640 [ 49.936077][ T7156] ? ip_queue_xmit+0x45/0x60 [ 49.940644][ T7156] ? vprintk_func+0x8d/0x140 [ 49.945215][ T7156] kcsan_report.cold+0xc/0x10 [ 49.949871][ T7156] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.955413][ T7156] __tsan_write4+0x32/0x40 [ 49.959809][ T7156] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.964900][ T7156] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.970442][ T7156] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.976054][ T7156] nf_conntrack_in+0x410/0xa80 [ 49.980809][ T7156] ipv4_conntrack_local+0xbe/0x130 [ 49.985902][ T7156] nf_hook_slow+0x83/0x160 [ 49.990307][ T7156] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 49.995064][ T7156] __ip_local_out+0x1f7/0x2b0 [ 49.999719][ T7156] ? constant_test_bit+0x30/0x30 [ 50.004648][ T7156] ip_local_out+0x31/0x90 [ 50.008959][ T7156] __ip_queue_xmit+0x3a8/0xa40 [ 50.013714][ T7156] ip_queue_xmit+0x45/0x60 [ 50.018112][ T7156] __tcp_transmit_skb+0xe81/0x1d60 [ 50.023271][ T7156] __tcp_send_ack+0x246/0x300 [ 50.027939][ T7156] tcp_send_ack+0x34/0x40 [ 50.032260][ T7156] tcp_cleanup_rbuf+0x130/0x360 [ 50.037093][ T7156] tcp_recvmsg+0x633/0x1a30 [ 50.041579][ T7156] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 50.047189][ T7156] inet_recvmsg+0xbb/0x250 [ 50.051580][ T7156] ? __tsan_read8+0x2c/0x30 [ 50.056061][ T7156] ? inet_sendpage+0x100/0x100 [ 50.060810][ T7156] sock_recvmsg+0x92/0xb0 [ 50.065123][ T7156] sock_read_iter+0x15f/0x1e0 [ 50.069781][ T7156] new_sync_read+0x389/0x4f0 [ 50.074354][ T7156] __vfs_read+0xb1/0xc0 [ 50.078488][ T7156] vfs_read+0x143/0x2c0 [ 50.082622][ T7156] ksys_read+0xd5/0x1b0 [ 50.086773][ T7156] __x64_sys_read+0x4c/0x60 [ 50.091266][ T7156] do_syscall_64+0xcc/0x370 [ 50.095748][ T7156] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.101628][ T7156] RIP: 0033:0x47c530 [ 50.105502][ T7156] 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 [ 50.125080][ T7156] RSP: 002b:000000c42048d810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 50.133469][ T7156] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.141503][ T7156] RDX: 0000000000001000 RSI: 000000c420304000 RDI: 0000000000000003 [ 50.149450][ T7156] RBP: 000000c42048d868 R08: 0000000000000000 R09: 0000000000000000 [ 50.157398][ T7156] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 50.165358][ T7156] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 50.174698][ T7156] Kernel Offset: disabled [ 50.179038][ T7156] Rebooting in 86400 seconds..