[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.749415][ T26] audit: type=1800 audit(1571710285.038:25): pid=6978 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [ 40.884355][ T26] audit: type=1800 audit(1571710285.178:26): pid=6978 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 40.936770][ T26] audit: type=1800 audit(1571710285.228:27): pid=6978 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 OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.1.8' (ECDSA) to the list of known hosts. 2019/10/22 02:11:36 fuzzer started 2019/10/22 02:11:37 dialing manager at 10.128.0.105:37053 2019/10/22 02:11:37 syscalls: 2524 2019/10/22 02:11:37 code coverage: enabled 2019/10/22 02:11:37 comparison tracing: enabled 2019/10/22 02:11:37 extra coverage: extra coverage is not supported by the kernel 2019/10/22 02:11:37 setuid sandbox: enabled 2019/10/22 02:11:37 namespace sandbox: enabled 2019/10/22 02:11:37 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 02:11:37 fault injection: enabled 2019/10/22 02:11:37 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 02:11:37 net packet injection: enabled 2019/10/22 02:11:37 net device setup: enabled 2019/10/22 02:11:37 concurrency sanitizer: enabled syzkaller login: [ 53.647088][ T7130] ================================================================== [ 53.655513][ T7130] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 53.663754][ T7130] [ 53.666075][ T7130] read to 0xffff88812ab85208 of 4 bytes by interrupt on cpu 1: [ 53.673706][ T7130] __nf_ct_refresh_acct+0xd4/0x1b0 [ 53.678846][ T7130] nf_conntrack_tcp_packet+0xd40/0x3390 [ 53.684894][ T7130] nf_conntrack_in+0x410/0xa80 [ 53.689722][ T7130] ipv4_conntrack_in+0x27/0x40 [ 53.694479][ T7130] nf_hook_slow+0x83/0x160 [ 53.698895][ T7130] ip_rcv+0x12f/0x1a0 [ 53.702855][ T7130] __netif_receive_skb_one_core+0xa7/0xe0 [ 53.708587][ T7130] __netif_receive_skb+0x37/0xf0 [ 53.713592][ T7130] netif_receive_skb_internal+0x59/0x190 [ 53.719412][ T7130] napi_gro_receive+0x28f/0x330 [ 53.724255][ T7130] receive_buf+0x284/0x30b0 [ 53.728748][ T7130] virtnet_poll+0x436/0x7d0 [ 53.733237][ T7130] net_rx_action+0x3ae/0xa90 [ 53.737811][ T7130] __do_softirq+0x115/0x33f [ 53.742289][ T7130] [ 53.744601][ T7130] write to 0xffff88812ab85208 of 4 bytes by task 7130 on cpu 0: [ 53.752209][ T7130] __nf_ct_refresh_acct+0xfb/0x1b0 [ 53.757296][ T7130] nf_conntrack_tcp_packet+0xd40/0x3390 [ 53.762816][ T7130] nf_conntrack_in+0x410/0xa80 [ 53.768166][ T7130] ipv4_conntrack_local+0xbe/0x130 [ 53.773257][ T7130] nf_hook_slow+0x83/0x160 [ 53.777651][ T7130] __ip_local_out+0x1f7/0x2b0 [ 53.782301][ T7130] ip_local_out+0x31/0x90 [ 53.786627][ T7130] __ip_queue_xmit+0x3a8/0xa40 [ 53.791382][ T7130] ip_queue_xmit+0x45/0x60 [ 53.795876][ T7130] __tcp_transmit_skb+0xe81/0x1d60 [ 53.800963][ T7130] __tcp_send_ack+0x246/0x300 [ 53.805614][ T7130] tcp_send_ack+0x34/0x40 [ 53.809932][ T7130] tcp_cleanup_rbuf+0x130/0x360 [ 53.816833][ T7130] [ 53.819135][ T7130] Reported by Kernel Concurrency Sanitizer on: [ 53.825266][ T7130] CPU: 0 PID: 7130 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 53.832708][ T7130] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.842748][ T7130] ================================================================== [ 53.850784][ T7130] Kernel panic - not syncing: panic_on_warn set ... [ 53.857369][ T7130] CPU: 0 PID: 7130 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 53.864811][ T7130] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.874839][ T7130] Call Trace: [ 53.878112][ T7130] dump_stack+0xf5/0x159 [ 53.882335][ T7130] panic+0x210/0x640 [ 53.886232][ T7130] ? ip_queue_xmit+0x45/0x60 [ 53.890816][ T7130] ? vprintk_func+0x8d/0x140 [ 53.895396][ T7130] kcsan_report.cold+0xc/0x10 [ 53.900176][ T7130] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 53.905835][ T7130] __tsan_write4+0x32/0x40 [ 53.910239][ T7130] __nf_ct_refresh_acct+0xfb/0x1b0 [ 53.915338][ T7130] nf_conntrack_tcp_packet+0xd40/0x3390 [ 53.920907][ T7130] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 53.926544][ T7130] nf_conntrack_in+0x410/0xa80 [ 53.931301][ T7130] ipv4_conntrack_local+0xbe/0x130 [ 53.936416][ T7130] nf_hook_slow+0x83/0x160 [ 53.940822][ T7130] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 53.945572][ T7130] __ip_local_out+0x1f7/0x2b0 [ 53.950233][ T7130] ? constant_test_bit+0x30/0x30 [ 53.955148][ T7130] ip_local_out+0x31/0x90 [ 53.959455][ T7130] __ip_queue_xmit+0x3a8/0xa40 [ 53.964204][ T7130] ip_queue_xmit+0x45/0x60 [ 53.968625][ T7130] __tcp_transmit_skb+0xe81/0x1d60 [ 53.973733][ T7130] __tcp_send_ack+0x246/0x300 [ 53.978394][ T7130] tcp_send_ack+0x34/0x40 [ 53.982805][ T7130] tcp_cleanup_rbuf+0x130/0x360 [ 53.987641][ T7130] tcp_recvmsg+0x633/0x1a30 [ 53.992131][ T7130] inet_recvmsg+0xbb/0x250 [ 53.996527][ T7130] ? __tsan_read8+0x2c/0x30 [ 54.001102][ T7130] ? inet_sendpage+0x100/0x100 [ 54.005872][ T7130] sock_recvmsg+0x92/0xb0 [ 54.010190][ T7130] sock_read_iter+0x15f/0x1e0 [ 54.014865][ T7130] new_sync_read+0x389/0x4f0 [ 54.019490][ T7130] __vfs_read+0xb1/0xc0 [ 54.023646][ T7130] vfs_read+0x143/0x2c0 [ 54.027789][ T7130] ksys_read+0xd5/0x1b0 [ 54.031928][ T7130] __x64_sys_read+0x4c/0x60 [ 54.036533][ T7130] do_syscall_64+0xcc/0x370 [ 54.041030][ T7130] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 54.046926][ T7130] RIP: 0033:0x47c530 [ 54.050813][ T7130] 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 [ 54.070396][ T7130] RSP: 002b:000000c4204e1810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 54.078792][ T7130] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 54.086747][ T7130] RDX: 0000000000001000 RSI: 000000c4202fa000 RDI: 0000000000000003 [ 54.094718][ T7130] RBP: 000000c4204e1868 R08: 0000000000000000 R09: 0000000000000000 [ 54.102856][ T7130] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 54.110840][ T7130] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 54.120189][ T7130] Kernel Offset: disabled [ 54.124535][ T7130] Rebooting in 86400 seconds..