[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.962599][ T25] audit: type=1800 audit(1570684234.074:25): pid=7044 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.003832][ T25] audit: type=1800 audit(1570684234.074:26): pid=7044 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.024153][ T25] audit: type=1800 audit(1570684234.074:27): pid=7044 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 '10.128.0.131' (ECDSA) to the list of known hosts. 2019/10/10 05:10:44 fuzzer started 2019/10/10 05:10:45 dialing manager at 10.128.0.105:43471 2019/10/10 05:10:45 syscalls: 2523 2019/10/10 05:10:45 code coverage: enabled 2019/10/10 05:10:45 comparison tracing: enabled 2019/10/10 05:10:45 extra coverage: extra coverage is not supported by the kernel 2019/10/10 05:10:45 setuid sandbox: enabled 2019/10/10 05:10:45 namespace sandbox: enabled 2019/10/10 05:10:45 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/10 05:10:45 fault injection: enabled 2019/10/10 05:10:45 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/10 05:10:45 net packet injection: enabled 2019/10/10 05:10:45 net device setup: enabled 2019/10/10 05:10:45 concurrency sanitizer: enabled syzkaller login: [ 46.856602][ T7199] ================================================================== [ 46.864738][ T7199] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 46.871141][ T7199] [ 46.873474][ T7199] write to 0xffff88812a90c5b4 of 4 bytes by task 7204 on cpu 0: [ 46.881102][ T7199] tcp_recvmsg+0xd86/0x1a30 [ 46.885608][ T7199] inet_recvmsg+0xbb/0x250 [ 46.890000][ T7199] sock_recvmsg+0x92/0xb0 [ 46.894304][ T7199] sock_read_iter+0x15f/0x1e0 [ 46.898983][ T7199] new_sync_read+0x389/0x4f0 [ 46.903550][ T7199] __vfs_read+0xb1/0xc0 [ 46.907727][ T7199] vfs_read+0x143/0x2c0 [ 46.911871][ T7199] ksys_read+0xd5/0x1b0 [ 46.916004][ T7199] __x64_sys_read+0x4c/0x60 [ 46.920490][ T7199] do_syscall_64+0xcf/0x2f0 [ 46.924974][ T7199] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.931032][ T7199] [ 46.933338][ T7199] read to 0xffff88812a90c5b4 of 4 bytes by task 7199 on cpu 1: [ 46.940865][ T7199] tcp_poll+0x1cc/0x6b0 [ 46.944993][ T7199] sock_poll+0xed/0x250 [ 46.949128][ T7199] ep_item_poll.isra.0+0x90/0x190 [ 46.954130][ T7199] ep_send_events_proc+0x113/0x5c0 [ 46.961823][ T7199] ep_scan_ready_list.constprop.0+0x189/0x500 [ 46.967865][ T7199] ep_poll+0xe3/0x900 [ 46.971824][ T7199] do_epoll_wait+0x162/0x180 [ 46.976407][ T7199] __x64_sys_epoll_pwait+0xcd/0x170 [ 46.981595][ T7199] do_syscall_64+0xcf/0x2f0 [ 46.986077][ T7199] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.991936][ T7199] [ 46.994256][ T7199] Reported by Kernel Concurrency Sanitizer on: [ 47.000384][ T7199] CPU: 1 PID: 7199 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.007464][ T7199] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.017511][ T7199] ================================================================== [ 47.025547][ T7199] Kernel panic - not syncing: panic_on_warn set ... [ 47.032111][ T7199] CPU: 1 PID: 7199 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.039190][ T7199] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.049228][ T7199] Call Trace: [ 47.052504][ T7199] dump_stack+0xf5/0x159 [ 47.056741][ T7199] panic+0x209/0x639 [ 47.060620][ T7199] ? do_syscall_64+0xcf/0x2f0 [ 47.065366][ T7199] ? vprintk_func+0x8d/0x140 [ 47.070051][ T7199] kcsan_report.cold+0xc/0x1b [ 47.074718][ T7199] __kcsan_setup_watchpoint+0x3ee/0x510 [ 47.080338][ T7199] __tsan_read4+0x2c/0x30 [ 47.084652][ T7199] tcp_poll+0x1cc/0x6b0 [ 47.088805][ T7199] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 47.094263][ T7199] sock_poll+0xed/0x250 [ 47.098408][ T7199] ? sock_read_iter+0x1e0/0x1e0 [ 47.104467][ T7199] ep_item_poll.isra.0+0x90/0x190 [ 47.109483][ T7199] ep_send_events_proc+0x113/0x5c0 [ 47.114584][ T7199] ? hrtimer_active+0x1a0/0x1a0 [ 47.119429][ T7199] ? __kcsan_setup_watchpoint+0x96/0x510 [ 47.125053][ T7199] ep_scan_ready_list.constprop.0+0x189/0x500 [ 47.131134][ T7199] ? ep_loop_check_proc+0x2f0/0x2f0 [ 47.136325][ T7199] ep_poll+0xe3/0x900 [ 47.140315][ T7199] ? wake_up_q+0x70/0x70 [ 47.144554][ T7199] do_epoll_wait+0x162/0x180 [ 47.149130][ T7199] __x64_sys_epoll_pwait+0xcd/0x170 [ 47.154312][ T7199] do_syscall_64+0xcf/0x2f0 [ 47.158814][ T7199] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.164707][ T7199] RIP: 0033:0x45b300 [ 47.168594][ T7199] Code: 0f 05 89 44 24 20 c3 cc cc cc 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 44 8b 54 24 1c 49 c7 c0 00 00 00 00 b8 19 01 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc cc cc cc cc cc cc cc 8b 7c 24 08 48 c7 [ 47.189140][ T7199] RSP: 002b:00007ffce25a0b90 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 47.197536][ T7199] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 47.205535][ T7199] RDX: 0000000000000080 RSI: 00007ffce25a0bd0 RDI: 0000000000000004 [ 47.213491][ T7199] RBP: 00007ffce25a11d0 R08: 0000000000000000 R09: 00000000018031a0 [ 47.221446][ T7199] R10: 00000000ffffffff R11: 0000000000000246 R12: 000000c420338000 [ 47.229486][ T7199] R13: 0000000000000022 R14: 0000000000000000 R15: 0000000000000000 [ 47.238840][ T7199] Kernel Offset: disabled [ 47.243237][ T7199] Rebooting in 86400 seconds..