[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.775668][ T23] audit: type=1800 audit(1571046705.906:25): pid=7102 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.825387][ T23] audit: type=1800 audit(1571046705.916:26): pid=7102 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.846308][ T23] audit: type=1800 audit(1571046705.916:27): pid=7102 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 '10.128.15.207' (ECDSA) to the list of known hosts. 2019/10/14 09:51:53 fuzzer started 2019/10/14 09:51:54 dialing manager at 10.128.0.105:43961 2019/10/14 09:51:54 syscalls: 2523 2019/10/14 09:51:54 code coverage: enabled 2019/10/14 09:51:54 comparison tracing: enabled 2019/10/14 09:51:54 extra coverage: extra coverage is not supported by the kernel 2019/10/14 09:51:54 setuid sandbox: enabled 2019/10/14 09:51:54 namespace sandbox: enabled 2019/10/14 09:51:54 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/14 09:51:54 fault injection: enabled 2019/10/14 09:51:54 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/14 09:51:54 net packet injection: enabled 2019/10/14 09:51:54 net device setup: enabled 2019/10/14 09:51:54 concurrency sanitizer: enabled syzkaller login: [ 46.569532][ T7264] ================================================================== [ 46.577770][ T7264] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 46.584154][ T7264] [ 46.586466][ T7264] write to 0xffff888126fcf7b4 of 4 bytes by task 7265 on cpu 0: [ 46.594072][ T7264] tcp_recvmsg+0xd86/0x1a30 [ 46.598906][ T7264] inet_recvmsg+0xbb/0x250 [ 46.603327][ T7264] sock_recvmsg+0x92/0xb0 [ 46.607663][ T7264] sock_read_iter+0x15f/0x1e0 [ 46.612469][ T7264] new_sync_read+0x389/0x4f0 [ 46.617053][ T7264] __vfs_read+0xb1/0xc0 [ 46.621205][ T7264] vfs_read+0x143/0x2c0 [ 46.625340][ T7264] ksys_read+0xd5/0x1b0 [ 46.629475][ T7264] __x64_sys_read+0x4c/0x60 [ 46.633956][ T7264] do_syscall_64+0xcf/0x2f0 [ 46.639057][ T7264] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.644919][ T7264] [ 46.647227][ T7264] read to 0xffff888126fcf7b4 of 4 bytes by task 7264 on cpu 1: [ 46.654752][ T7264] tcp_poll+0x1cc/0x6b0 [ 46.658891][ T7264] sock_poll+0xed/0x250 [ 46.663025][ T7264] ep_item_poll.isra.0+0x90/0x190 [ 46.668026][ T7264] ep_send_events_proc+0x113/0x5c0 [ 46.673385][ T7264] ep_scan_ready_list.constprop.0+0x189/0x500 [ 46.679443][ T7264] ep_poll+0xe3/0x900 [ 46.683402][ T7264] do_epoll_wait+0x162/0x180 [ 46.687969][ T7264] __x64_sys_epoll_pwait+0xcd/0x170 [ 46.693239][ T7264] do_syscall_64+0xcf/0x2f0 [ 46.697724][ T7264] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.703684][ T7264] [ 46.705984][ T7264] Reported by Kernel Concurrency Sanitizer on: [ 46.712129][ T7264] CPU: 1 PID: 7264 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.719212][ T7264] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.729245][ T7264] ================================================================== [ 46.737721][ T7264] Kernel panic - not syncing: panic_on_warn set ... [ 46.744291][ T7264] CPU: 1 PID: 7264 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.751459][ T7264] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.761493][ T7264] Call Trace: [ 46.764772][ T7264] dump_stack+0xf5/0x159 [ 46.769001][ T7264] panic+0x209/0x639 [ 46.772896][ T7264] ? do_syscall_64+0xcf/0x2f0 [ 46.778564][ T7264] ? vprintk_func+0x8d/0x140 [ 46.783147][ T7264] kcsan_report.cold+0xc/0x1b [ 46.787809][ T7264] __kcsan_setup_watchpoint+0x3ee/0x510 [ 46.793357][ T7264] __tsan_read4+0x2c/0x30 [ 46.797701][ T7264] tcp_poll+0x1cc/0x6b0 [ 46.801856][ T7264] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 46.807292][ T7264] sock_poll+0xed/0x250 [ 46.811948][ T7264] ? sock_read_iter+0x1e0/0x1e0 [ 46.816792][ T7264] ep_item_poll.isra.0+0x90/0x190 [ 46.821813][ T7264] ep_send_events_proc+0x113/0x5c0 [ 46.826903][ T7264] ? __kcsan_setup_watchpoint+0x96/0x510 [ 46.832646][ T7264] ep_scan_ready_list.constprop.0+0x189/0x500 [ 46.838727][ T7264] ? ep_loop_check_proc+0x2f0/0x2f0 [ 46.843909][ T7264] ep_poll+0xe3/0x900 [ 46.847965][ T7264] ? wake_up_q+0x70/0x70 [ 46.852191][ T7264] do_epoll_wait+0x162/0x180 [ 46.856767][ T7264] __x64_sys_epoll_pwait+0xcd/0x170 [ 46.861960][ T7264] do_syscall_64+0xcf/0x2f0 [ 46.866449][ T7264] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.872315][ T7264] RIP: 0033:0x45b300 [ 46.876300][ T7264] 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 [ 46.895893][ T7264] RSP: 002b:000000c4203bd860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 46.904382][ T7264] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 46.912349][ T7264] RDX: 0000000000000080 RSI: 000000c4203bd8a0 RDI: 0000000000000004 [ 46.920301][ T7264] RBP: 000000c4203bdea0 R08: 0000000000000000 R09: 000000c42006f200 [ 46.928247][ T7264] R10: 00000000ffffffff R11: 0000000000000246 R12: 00000000000000a0 [ 46.936194][ T7264] R13: 00000000000000ff R14: 00007f95f8d0a000 R15: 0000000000000004 [ 46.945618][ T7264] Kernel Offset: disabled [ 46.950168][ T7264] Rebooting in 86400 seconds..