[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.405254][ T26] audit: type=1800 audit(1572090455.011:25): pid=7085 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.432780][ T26] audit: type=1800 audit(1572090455.011:26): pid=7085 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.460686][ T26] audit: type=1800 audit(1572090455.011:27): pid=7085 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 '10.128.0.69' (ECDSA) to the list of known hosts. 2019/10/26 11:47:47 fuzzer started 2019/10/26 11:47:49 dialing manager at 10.128.0.105:33655 2019/10/26 11:47:49 syscalls: 2533 2019/10/26 11:47:49 code coverage: enabled 2019/10/26 11:47:49 comparison tracing: enabled 2019/10/26 11:47:49 extra coverage: extra coverage is not supported by the kernel 2019/10/26 11:47:49 setuid sandbox: enabled 2019/10/26 11:47:49 namespace sandbox: enabled 2019/10/26 11:47:49 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/26 11:47:49 fault injection: enabled 2019/10/26 11:47:49 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/26 11:47:49 net packet injection: enabled 2019/10/26 11:47:49 net device setup: enabled 2019/10/26 11:47:49 concurrency sanitizer: enabled 2019/10/26 11:47:52 adding functions to KCSAN blacklist: 'find_next_bit' '__ext4_new_inode' '__nf_conntrack_find_get' 'ep_poll' 'tomoyo_supervisor' 'pipe_poll' 'rcu_gp_fqs_check_wake' 'pid_update_inode' 'tcp_poll' 'find_get_pages_range_tag' 'generic_permission' '__hrtimer_run_queues' 'tcp_add_backlog' 'ktime_get_real_seconds' 'do_nanosleep' syzkaller login: [ 56.255024][ T7255] ================================================================== [ 56.263437][ T7255] BUG: KCSAN: data-race in __nf_ct_refresh_acct / __nf_ct_refresh_acct [ 56.271657][ T7255] [ 56.273984][ T7255] read to 0xffff888129c39808 of 4 bytes by interrupt on cpu 0: [ 56.281522][ T7255] __nf_ct_refresh_acct+0xd4/0x1b0 [ 56.286627][ T7255] nf_conntrack_tcp_packet+0xd40/0x3390 [ 56.292170][ T7255] nf_conntrack_in+0x410/0xa80 [ 56.296930][ T7255] ipv4_conntrack_in+0x27/0x40 [ 56.301792][ T7255] nf_hook_slow+0x83/0x160 [ 56.306181][ T7255] ip_rcv+0x12f/0x1a0 [ 56.310154][ T7255] __netif_receive_skb_one_core+0xa7/0xe0 [ 56.315934][ T7255] __netif_receive_skb+0x37/0xf0 [ 56.320854][ T7255] netif_receive_skb_internal+0x59/0x190 [ 56.329035][ T7255] napi_gro_receive+0x28f/0x330 [ 56.336975][ T7255] receive_buf+0x284/0x30b0 [ 56.342428][ T7255] virtnet_poll+0x436/0x7d0 [ 56.346952][ T7255] net_rx_action+0x3ae/0xa90 [ 56.351523][ T7255] __do_softirq+0x115/0x33f [ 56.355996][ T7255] [ 56.358305][ T7255] write to 0xffff888129c39808 of 4 bytes by task 7255 on cpu 1: [ 56.365913][ T7255] __nf_ct_refresh_acct+0xfb/0x1b0 [ 56.371051][ T7255] nf_conntrack_tcp_packet+0xd40/0x3390 [ 56.376720][ T7255] nf_conntrack_in+0x410/0xa80 [ 56.381591][ T7255] ipv4_conntrack_local+0xbe/0x130 [ 56.386683][ T7255] nf_hook_slow+0x83/0x160 [ 56.391210][ T7255] __ip_local_out+0x1f7/0x2b0 [ 56.395861][ T7255] ip_local_out+0x31/0x90 [ 56.400182][ T7255] __ip_queue_xmit+0x3a8/0xa40 [ 56.404920][ T7255] ip_queue_xmit+0x45/0x60 [ 56.409366][ T7255] __tcp_transmit_skb+0xe81/0x1d60 [ 56.414482][ T7255] __tcp_send_ack+0x246/0x300 [ 56.419183][ T7255] tcp_send_ack+0x34/0x40 [ 56.423490][ T7255] tcp_cleanup_rbuf+0x130/0x360 [ 56.428308][ T7255] [ 56.431312][ T7255] Reported by Kernel Concurrency Sanitizer on: [ 56.437498][ T7255] CPU: 1 PID: 7255 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 56.445319][ T7255] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.455463][ T7255] ================================================================== [ 56.463792][ T7255] Kernel panic - not syncing: panic_on_warn set ... [ 56.470364][ T7255] CPU: 1 PID: 7255 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 56.477795][ T7255] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.487827][ T7255] Call Trace: [ 56.491122][ T7255] dump_stack+0xf5/0x159 [ 56.495361][ T7255] panic+0x210/0x640 [ 56.499234][ T7255] ? ip_queue_xmit+0x45/0x60 [ 56.504401][ T7255] ? vprintk_func+0x8d/0x140 [ 56.509509][ T7255] kcsan_report.cold+0xc/0x10 [ 56.514186][ T7255] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 56.519716][ T7255] __tsan_write4+0x32/0x40 [ 56.524135][ T7255] __nf_ct_refresh_acct+0xfb/0x1b0 [ 56.529244][ T7255] nf_conntrack_tcp_packet+0xd40/0x3390 [ 56.534925][ T7255] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 56.540666][ T7255] nf_conntrack_in+0x410/0xa80 [ 56.545415][ T7255] ipv4_conntrack_local+0xbe/0x130 [ 56.550523][ T7255] nf_hook_slow+0x83/0x160 [ 56.554944][ T7255] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 56.559708][ T7255] __ip_local_out+0x1f7/0x2b0 [ 56.564389][ T7255] ? constant_test_bit+0x30/0x30 [ 56.569312][ T7255] ip_local_out+0x31/0x90 [ 56.573622][ T7255] __ip_queue_xmit+0x3a8/0xa40 [ 56.578391][ T7255] ip_queue_xmit+0x45/0x60 [ 56.582800][ T7255] __tcp_transmit_skb+0xe81/0x1d60 [ 56.587901][ T7255] __tcp_send_ack+0x246/0x300 [ 56.593183][ T7255] tcp_send_ack+0x34/0x40 [ 56.597489][ T7255] tcp_cleanup_rbuf+0x130/0x360 [ 56.602332][ T7255] tcp_recvmsg+0x633/0x1a30 [ 56.607442][ T7255] inet_recvmsg+0xbb/0x250 [ 56.611840][ T7255] ? __tsan_read8+0x2c/0x30 [ 56.616329][ T7255] ? inet_sendpage+0x100/0x100 [ 56.621084][ T7255] sock_recvmsg+0x92/0xb0 [ 56.625411][ T7255] sock_read_iter+0x15f/0x1e0 [ 56.630077][ T7255] new_sync_read+0x389/0x4f0 [ 56.634666][ T7255] __vfs_read+0xb1/0xc0 [ 56.638820][ T7255] vfs_read+0x143/0x2c0 [ 56.643072][ T7255] ksys_read+0xd5/0x1b0 [ 56.647287][ T7255] __x64_sys_read+0x4c/0x60 [ 56.651796][ T7255] do_syscall_64+0xcc/0x370 [ 56.656297][ T7255] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 56.662171][ T7255] RIP: 0033:0x47c530 [ 56.666332][ T7255] 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 [ 56.686840][ T7255] RSP: 002b:000000c4204bd810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 56.695239][ T7255] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 56.703190][ T7255] RDX: 0000000000001000 RSI: 000000c420318000 RDI: 0000000000000003 [ 56.711140][ T7255] RBP: 000000c4204bd868 R08: 0000000000000000 R09: 0000000000000000 [ 56.719955][ T7255] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000010 [ 56.727902][ T7255] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 56.737300][ T7255] Kernel Offset: disabled [ 56.741622][ T7255] Rebooting in 86400 seconds..