[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.430366][ T25] audit: type=1800 audit(1570650805.387:25): pid=7079 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.457480][ T25] audit: type=1800 audit(1570650805.387:26): pid=7079 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.484239][ T25] audit: type=1800 audit(1570650805.387:27): pid=7079 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 '10.128.0.9' (ECDSA) to the list of known hosts. 2019/10/09 19:53:35 fuzzer started 2019/10/09 19:53:37 dialing manager at 10.128.0.105:43471 2019/10/09 19:53:37 syscalls: 2523 2019/10/09 19:53:37 code coverage: enabled 2019/10/09 19:53:37 comparison tracing: enabled 2019/10/09 19:53:37 extra coverage: extra coverage is not supported by the kernel 2019/10/09 19:53:37 setuid sandbox: enabled 2019/10/09 19:53:37 namespace sandbox: enabled 2019/10/09 19:53:37 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/09 19:53:37 fault injection: enabled 2019/10/09 19:53:37 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/09 19:53:37 net packet injection: enabled 2019/10/09 19:53:37 net device setup: enabled 2019/10/09 19:53:37 concurrency sanitizer: enabled syzkaller login: [ 47.831009][ T7227] ================================================================== [ 47.839130][ T7227] BUG: KCSAN: data-race in mod_timer / timer_clear_idle [ 47.846036][ T7227] [ 47.848361][ T7227] write to 0xffff88812be1b6e4 of 1 bytes by task 0 on cpu 0: [ 47.855715][ T7227] timer_clear_idle+0x42/0x50 [ 47.860376][ T7227] __tick_nohz_idle_restart_tick+0x36/0x1b0 [ 47.866291][ T7227] tick_nohz_idle_exit+0x1af/0x1e0 [ 47.871388][ T7227] do_idle+0xb0/0x2c0 [ 47.875349][ T7227] cpu_startup_entry+0x1b/0x20 [ 47.880092][ T7227] rest_init+0xec/0xf6 [ 47.884150][ T7227] arch_call_rest_init+0x17/0x37 [ 47.889072][ T7227] start_kernel+0x83e/0x864 [ 47.893560][ T7227] x86_64_start_reservations+0x29/0x2b [ 47.899002][ T7227] x86_64_start_kernel+0x72/0x76 [ 47.903920][ T7227] secondary_startup_64+0xa4/0xb0 [ 47.908926][ T7227] [ 47.911240][ T7227] read to 0xffff88812be1b6e4 of 1 bytes by task 7227 on cpu 1: [ 47.918766][ T7227] mod_timer+0x50d/0x7a0 [ 47.922992][ T7227] sk_reset_timer+0x2d/0x70 [ 47.927477][ T7227] tcp_rearm_rto.part.0+0x190/0x240 [ 47.932658][ T7227] tcp_rearm_rto+0x4f/0x60 [ 47.937057][ T7227] tcp_event_new_data_sent+0x1bb/0x1c0 [ 47.942496][ T7227] tcp_write_xmit+0xa16/0x3080 [ 47.947243][ T7227] __tcp_push_pending_frames+0x7b/0x1d0 [ 47.952766][ T7227] tcp_push+0x1e9/0x3d0 [ 47.956904][ T7227] tcp_sendmsg_locked+0x1d1b/0x1ef0 [ 47.962082][ T7227] tcp_sendmsg+0x39/0x60 [ 47.966360][ T7227] inet_sendmsg+0x6d/0x90 [ 47.970683][ T7227] sock_sendmsg+0x9f/0xc0 [ 47.974999][ T7227] sock_write_iter+0x16b/0x210 [ 47.979741][ T7227] [ 47.982052][ T7227] Reported by Kernel Concurrency Sanitizer on: [ 47.988196][ T7227] CPU: 1 PID: 7227 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.995287][ T7227] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.005323][ T7227] ================================================================== [ 48.013361][ T7227] Kernel panic - not syncing: panic_on_warn set ... [ 48.019933][ T7227] CPU: 1 PID: 7227 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.027016][ T7227] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.037049][ T7227] Call Trace: [ 48.040336][ T7227] dump_stack+0xf5/0x159 [ 48.044566][ T7227] panic+0x209/0x639 [ 48.048447][ T7227] ? tcp_sendmsg_locked+0x1d1b/0x1ef0 [ 48.053803][ T7227] ? vprintk_func+0x8d/0x140 [ 48.058382][ T7227] kcsan_report.cold+0xc/0x1b [ 48.063058][ T7227] __kcsan_setup_watchpoint+0x3ee/0x510 [ 48.068590][ T7227] __tsan_read1+0x2c/0x30 [ 48.072906][ T7227] mod_timer+0x50d/0x7a0 [ 48.077133][ T7227] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.082748][ T7227] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.088371][ T7227] sk_reset_timer+0x2d/0x70 [ 48.092858][ T7227] tcp_rearm_rto.part.0+0x190/0x240 [ 48.098044][ T7227] tcp_rearm_rto+0x4f/0x60 [ 48.102446][ T7227] tcp_event_new_data_sent+0x1bb/0x1c0 [ 48.107890][ T7227] tcp_write_xmit+0xa16/0x3080 [ 48.112643][ T7227] ? kmem_cache_alloc_node_trace+0x273/0x670 [ 48.118617][ T7227] __tcp_push_pending_frames+0x7b/0x1d0 [ 48.124147][ T7227] tcp_push+0x1e9/0x3d0 [ 48.128294][ T7227] tcp_sendmsg_locked+0x1d1b/0x1ef0 [ 48.133487][ T7227] tcp_sendmsg+0x39/0x60 [ 48.137717][ T7227] inet_sendmsg+0x6d/0x90 [ 48.142031][ T7227] ? inet_send_prepare+0x200/0x200 [ 48.147127][ T7227] sock_sendmsg+0x9f/0xc0 [ 48.151460][ T7227] sock_write_iter+0x16b/0x210 [ 48.156217][ T7227] new_sync_write+0x388/0x4a0 [ 48.160884][ T7227] __vfs_write+0xb1/0xc0 [ 48.165122][ T7227] vfs_write+0x18a/0x390 [ 48.169353][ T7227] ksys_write+0xd5/0x1b0 [ 48.173582][ T7227] __x64_sys_write+0x4c/0x60 [ 48.178159][ T7227] do_syscall_64+0xcf/0x2f0 [ 48.182652][ T7227] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.188523][ T7227] RIP: 0033:0x47c530 [ 48.192415][ T7227] 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 [ 48.212001][ T7227] RSP: 002b:000000c4202774f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000001 [ 48.220395][ T7227] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.228346][ T7227] RDX: 0000000000000007 RSI: 000000c42038a020 RDI: 0000000000000003 [ 48.236300][ T7227] RBP: 000000c420277550 R08: 0000000000000000 R09: 0000000000000000 [ 48.244256][ T7227] R10: 0000000000000000 R11: 0000000000000216 R12: 000000c4200c5b00 [ 48.252214][ T7227] R13: 0000000000000007 R14: 0000000000c11600 R15: 00000000000011e7 [ 49.391636][ T7227] Shutting down cpus with NMI [ 49.398065][ T7227] Kernel Offset: disabled [ 49.402381][ T7227] Rebooting in 86400 seconds..