[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.590739][ T25] audit: type=1800 audit(1570855557.777:25): pid=7090 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.618353][ T25] audit: type=1800 audit(1570855557.777:26): pid=7090 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.638479][ T25] audit: type=1800 audit(1570855557.777:27): pid=7090 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 '10.128.0.109' (ECDSA) to the list of known hosts. 2019/10/12 04:46:08 fuzzer started 2019/10/12 04:46:09 dialing manager at 10.128.0.105:43913 2019/10/12 04:46:09 syscalls: 2523 2019/10/12 04:46:09 code coverage: enabled 2019/10/12 04:46:09 comparison tracing: enabled 2019/10/12 04:46:09 extra coverage: extra coverage is not supported by the kernel 2019/10/12 04:46:09 setuid sandbox: enabled 2019/10/12 04:46:09 namespace sandbox: enabled 2019/10/12 04:46:09 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/12 04:46:09 fault injection: enabled 2019/10/12 04:46:09 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/12 04:46:09 net packet injection: enabled 2019/10/12 04:46:09 net device setup: enabled 2019/10/12 04:46:09 concurrency sanitizer: enabled syzkaller login: [ 48.269702][ T7256] ================================================================== [ 48.277926][ T7256] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 48.284322][ T7256] [ 48.286643][ T7256] write to 0xffff888125497774 of 4 bytes by task 7241 on cpu 0: [ 48.294838][ T7256] tcp_recvmsg+0xd86/0x1a30 [ 48.299363][ T7256] inet_recvmsg+0xbb/0x250 [ 48.303773][ T7256] sock_recvmsg+0x92/0xb0 [ 48.308161][ T7256] sock_read_iter+0x15f/0x1e0 [ 48.312871][ T7256] new_sync_read+0x389/0x4f0 [ 48.317458][ T7256] __vfs_read+0xb1/0xc0 [ 48.321627][ T7256] vfs_read+0x143/0x2c0 [ 48.325796][ T7256] ksys_read+0xd5/0x1b0 [ 48.329947][ T7256] __x64_sys_read+0x4c/0x60 [ 48.334458][ T7256] do_syscall_64+0xcf/0x2f0 [ 48.338964][ T7256] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.344842][ T7256] [ 48.347175][ T7256] read to 0xffff888125497774 of 4 bytes by task 7256 on cpu 1: [ 48.354718][ T7256] tcp_poll+0x1cc/0x6b0 [ 48.358912][ T7256] sock_poll+0xed/0x250 [ 48.363071][ T7256] ep_item_poll.isra.0+0x90/0x190 [ 48.368094][ T7256] ep_send_events_proc+0x113/0x5c0 [ 48.373296][ T7256] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.379358][ T7256] ep_poll+0xe3/0x900 [ 48.383379][ T7256] do_epoll_wait+0x162/0x180 [ 48.387964][ T7256] __x64_sys_epoll_pwait+0xcd/0x170 [ 48.393155][ T7256] do_syscall_64+0xcf/0x2f0 [ 48.397667][ T7256] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.403540][ T7256] [ 48.405845][ T7256] Reported by Kernel Concurrency Sanitizer on: [ 48.411992][ T7256] CPU: 1 PID: 7256 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.419097][ T7256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.429145][ T7256] ================================================================== [ 48.437196][ T7256] Kernel panic - not syncing: panic_on_warn set ... [ 48.443867][ T7256] CPU: 1 PID: 7256 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.450959][ T7256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.461017][ T7256] Call Trace: [ 48.464302][ T7256] dump_stack+0xf5/0x159 [ 48.469302][ T7256] panic+0x209/0x639 [ 48.473270][ T7256] ? do_syscall_64+0xcf/0x2f0 [ 48.477956][ T7256] ? vprintk_func+0x8d/0x140 [ 48.482545][ T7256] kcsan_report.cold+0xc/0x1b [ 48.487236][ T7256] __kcsan_setup_watchpoint+0x3ee/0x510 [ 48.492782][ T7256] __tsan_read4+0x2c/0x30 [ 48.497107][ T7256] tcp_poll+0x1cc/0x6b0 [ 48.501275][ T7256] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 48.506762][ T7256] sock_poll+0xed/0x250 [ 48.510962][ T7256] ? sock_read_iter+0x1e0/0x1e0 [ 48.515844][ T7256] ep_item_poll.isra.0+0x90/0x190 [ 48.521080][ T7256] ep_send_events_proc+0x113/0x5c0 [ 48.527278][ T7256] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.532924][ T7256] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.539006][ T7256] ? ep_loop_check_proc+0x2f0/0x2f0 [ 48.544201][ T7256] ep_poll+0xe3/0x900 [ 48.548222][ T7256] ? __fget+0xb8/0x1d0 [ 48.552311][ T7256] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.557968][ T7256] ? __fget_light+0xaf/0x190 [ 48.562559][ T7256] do_epoll_wait+0x162/0x180 [ 48.567146][ T7256] __x64_sys_epoll_pwait+0xcd/0x170 [ 48.572351][ T7256] do_syscall_64+0xcf/0x2f0 [ 48.576863][ T7256] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.582749][ T7256] RIP: 0033:0x45b300 [ 48.586636][ T7256] 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 [ 48.606236][ T7256] RSP: 002b:000000c4203bb860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 48.614716][ T7256] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b300 [ 48.623823][ T7256] RDX: 0000000000000080 RSI: 000000c4203bb8a0 RDI: 0000000000000004 [ 48.631796][ T7256] RBP: 000000c4203bbea0 R08: 0000000000000000 R09: 0000000000002206 [ 48.639771][ T7256] R10: 0000000000000000 R11: 0000000000000246 R12: 000000c420299000 [ 48.647747][ T7256] R13: 0000000000000023 R14: 0000000000000000 R15: 0000000000000000 [ 48.656952][ T7256] Kernel Offset: disabled [ 48.661282][ T7256] Rebooting in 86400 seconds..