[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.678444][ T26] audit: type=1800 audit(1571748774.643:25): pid=7062 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.698305][ T26] audit: type=1800 audit(1571748774.643:26): pid=7062 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.720000][ T26] audit: type=1800 audit(1571748774.643:27): pid=7062 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 '10.128.0.241' (ECDSA) to the list of known hosts. 2019/10/22 12:53:04 fuzzer started 2019/10/22 12:53:06 dialing manager at 10.128.0.105:37053 2019/10/22 12:53:06 syscalls: 2524 2019/10/22 12:53:06 code coverage: enabled 2019/10/22 12:53:06 comparison tracing: enabled 2019/10/22 12:53:06 extra coverage: extra coverage is not supported by the kernel 2019/10/22 12:53:06 setuid sandbox: enabled 2019/10/22 12:53:06 namespace sandbox: enabled 2019/10/22 12:53:06 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 12:53:06 fault injection: enabled 2019/10/22 12:53:06 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 12:53:06 net packet injection: enabled 2019/10/22 12:53:06 net device setup: enabled 2019/10/22 12:53:06 concurrency sanitizer: enabled syzkaller login: [ 49.035475][ T7233] ================================================================== [ 49.043733][ T7233] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 49.051962][ T7233] [ 49.054422][ T7233] read to 0xffff888122cd9408 of 4 bytes by interrupt on cpu 0: [ 49.061973][ T7233] __nf_ct_refresh_acct+0xd4/0x1b0 [ 49.067090][ T7233] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.072907][ T7233] nf_conntrack_in+0x410/0xa80 [ 49.077945][ T7233] ipv4_conntrack_in+0x27/0x40 [ 49.082695][ T7233] nf_hook_slow+0x83/0x160 [ 49.087099][ T7233] ip_rcv+0x12f/0x1a0 [ 49.091156][ T7233] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.096890][ T7233] __netif_receive_skb+0x37/0xf0 [ 49.101901][ T7233] netif_receive_skb_internal+0x59/0x190 [ 49.107537][ T7233] napi_gro_receive+0x28f/0x330 [ 49.112381][ T7233] receive_buf+0x284/0x30b0 [ 49.117043][ T7233] virtnet_poll+0x436/0x7d0 [ 49.121593][ T7233] net_rx_action+0x3ae/0xa90 [ 49.126194][ T7233] __do_softirq+0x115/0x33f [ 49.130674][ T7233] [ 49.132990][ T7233] write to 0xffff888122cd9408 of 4 bytes by task 7233 on cpu 1: [ 49.140682][ T7233] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.145776][ T7233] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.151304][ T7233] nf_conntrack_in+0x410/0xa80 [ 49.156052][ T7233] ipv4_conntrack_local+0xbe/0x130 [ 49.161214][ T7233] nf_hook_slow+0x83/0x160 [ 49.165655][ T7233] __ip_local_out+0x1f7/0x2b0 [ 49.170532][ T7233] ip_local_out+0x31/0x90 [ 49.174871][ T7233] __ip_queue_xmit+0x3a8/0xa40 [ 49.179628][ T7233] ip_queue_xmit+0x45/0x60 [ 49.184323][ T7233] __tcp_transmit_skb+0xe81/0x1d60 [ 49.189432][ T7233] __tcp_send_ack+0x246/0x300 [ 49.194115][ T7233] tcp_send_ack+0x34/0x40 [ 49.198433][ T7233] tcp_cleanup_rbuf+0x130/0x360 [ 49.203289][ T7233] [ 49.205599][ T7233] Reported by Kernel Concurrency Sanitizer on: [ 49.211787][ T7233] CPU: 1 PID: 7233 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.219228][ T7233] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.229381][ T7233] ================================================================== [ 49.237425][ T7233] Kernel panic - not syncing: panic_on_warn set ... [ 49.244001][ T7233] CPU: 1 PID: 7233 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.251437][ T7233] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.261599][ T7233] Call Trace: [ 49.264968][ T7233] dump_stack+0xf5/0x159 [ 49.269241][ T7233] panic+0x210/0x640 [ 49.273125][ T7233] ? ip_queue_xmit+0x45/0x60 [ 49.278204][ T7233] ? vprintk_func+0x8d/0x140 [ 49.283108][ T7233] kcsan_report.cold+0xc/0x10 [ 49.287777][ T7233] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.293716][ T7233] __tsan_write4+0x32/0x40 [ 49.298204][ T7233] __nf_ct_refresh_acct+0xfb/0x1b0 [ 49.303317][ T7233] nf_conntrack_tcp_packet+0xd40/0x3390 [ 49.308875][ T7233] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 49.314595][ T7233] nf_conntrack_in+0x410/0xa80 [ 49.319481][ T7233] ipv4_conntrack_local+0xbe/0x130 [ 49.324681][ T7233] nf_hook_slow+0x83/0x160 [ 49.329131][ T7233] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 49.333879][ T7233] __ip_local_out+0x1f7/0x2b0 [ 49.338712][ T7233] ? constant_test_bit+0x30/0x30 [ 49.343787][ T7233] ip_local_out+0x31/0x90 [ 49.348107][ T7233] __ip_queue_xmit+0x3a8/0xa40 [ 49.352865][ T7233] ip_queue_xmit+0x45/0x60 [ 49.357276][ T7233] __tcp_transmit_skb+0xe81/0x1d60 [ 49.362608][ T7233] __tcp_send_ack+0x246/0x300 [ 49.367488][ T7233] tcp_send_ack+0x34/0x40 [ 49.371843][ T7233] tcp_cleanup_rbuf+0x130/0x360 [ 49.376680][ T7233] tcp_recvmsg+0x633/0x1a30 [ 49.381178][ T7233] inet_recvmsg+0xbb/0x250 [ 49.385583][ T7233] ? __tsan_read8+0x2c/0x30 [ 49.390105][ T7233] ? inet_sendpage+0x100/0x100 [ 49.394860][ T7233] sock_recvmsg+0x92/0xb0 [ 49.399182][ T7233] sock_read_iter+0x15f/0x1e0 [ 49.404047][ T7233] new_sync_read+0x389/0x4f0 [ 49.408653][ T7233] __vfs_read+0xb1/0xc0 [ 49.412793][ T7233] vfs_read+0x143/0x2c0 [ 49.416935][ T7233] ksys_read+0xd5/0x1b0 [ 49.421080][ T7233] __x64_sys_read+0x4c/0x60 [ 49.425587][ T7233] do_syscall_64+0xcc/0x370 [ 49.430168][ T7233] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.436047][ T7233] RIP: 0033:0x47c530 [ 49.440089][ T7233] 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 [ 49.460137][ T7233] RSP: 002b:000000c4202ef810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 49.468668][ T7233] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 49.476937][ T7233] RDX: 0000000000001000 RSI: 000000c42037e000 RDI: 0000000000000003 [ 49.485043][ T7233] RBP: 000000c4202ef868 R08: 0000000000000000 R09: 0000000000000000 [ 49.493232][ T7233] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000100 [ 49.501296][ T7233] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 49.511521][ T7233] Kernel Offset: disabled [ 49.515854][ T7233] Rebooting in 86400 seconds..