[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.597345][ T26] audit: type=1800 audit(1571447993.028:25): pid=7003 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.624519][ T26] audit: type=1800 audit(1571447993.028:26): pid=7003 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.645004][ T26] audit: type=1800 audit(1571447993.028:27): pid=7003 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 '10.128.0.203' (ECDSA) to the list of known hosts. 2019/10/19 01:19:59 fuzzer started 2019/10/19 01:20:00 dialing manager at 10.128.0.105:43535 2019/10/19 01:20:00 syscalls: 2524 2019/10/19 01:20:00 code coverage: enabled 2019/10/19 01:20:00 comparison tracing: enabled 2019/10/19 01:20:00 extra coverage: extra coverage is not supported by the kernel 2019/10/19 01:20:00 setuid sandbox: enabled 2019/10/19 01:20:00 namespace sandbox: enabled 2019/10/19 01:20:00 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/19 01:20:00 fault injection: enabled 2019/10/19 01:20:00 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/19 01:20:00 net packet injection: enabled 2019/10/19 01:20:00 net device setup: enabled 2019/10/19 01:20:00 concurrency sanitizer: enabled syzkaller login: [ 43.282930][ T7153] ================================================================== [ 43.291276][ T7153] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 43.297701][ T7153] [ 43.300012][ T7153] write to 0xffff888121d30ebc of 4 bytes by task 7165 on cpu 0: [ 43.307637][ T7153] tcp_recvmsg+0xd86/0x1a30 [ 43.312115][ T7153] inet_recvmsg+0xbb/0x250 [ 43.316506][ T7153] sock_recvmsg+0x92/0xb0 [ 43.320816][ T7153] sock_read_iter+0x15f/0x1e0 [ 43.325485][ T7153] new_sync_read+0x389/0x4f0 [ 43.330063][ T7153] __vfs_read+0xb1/0xc0 [ 43.334205][ T7153] vfs_read+0x143/0x2c0 [ 43.338349][ T7153] ksys_read+0xd5/0x1b0 [ 43.342494][ T7153] __x64_sys_read+0x4c/0x60 [ 43.346988][ T7153] do_syscall_64+0xcc/0x370 [ 43.351466][ T7153] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 43.357324][ T7153] [ 43.359631][ T7153] read to 0xffff888121d30ebc of 4 bytes by task 7153 on cpu 1: [ 43.367165][ T7153] tcp_poll+0x1cc/0x6b0 [ 43.371303][ T7153] sock_poll+0xed/0x250 [ 43.375436][ T7153] ep_item_poll.isra.0+0x90/0x190 [ 43.380447][ T7153] ep_send_events_proc+0x113/0x590 [ 43.385535][ T7153] ep_scan_ready_list.constprop.0+0x189/0x500 [ 43.391579][ T7153] ep_poll+0xe3/0x900 [ 43.395553][ T7153] do_epoll_wait+0x162/0x180 [ 43.400119][ T7153] __x64_sys_epoll_pwait+0xcd/0x180 [ 43.405301][ T7153] do_syscall_64+0xcc/0x370 [ 43.409781][ T7153] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 43.415641][ T7153] [ 43.417954][ T7153] Reported by Kernel Concurrency Sanitizer on: [ 43.424604][ T7153] CPU: 1 PID: 7153 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 43.432043][ T7153] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.442085][ T7153] ================================================================== [ 43.450131][ T7153] Kernel panic - not syncing: panic_on_warn set ... [ 43.456698][ T7153] CPU: 1 PID: 7153 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 43.464123][ T7153] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.474164][ T7153] Call Trace: [ 43.477438][ T7153] dump_stack+0xf5/0x159 [ 43.481674][ T7153] panic+0x210/0x640 [ 43.485549][ T7153] ? do_syscall_64+0xcc/0x370 [ 43.490204][ T7153] ? vprintk_func+0x8d/0x140 [ 43.494771][ T7153] kcsan_report.cold+0xc/0x10 [ 43.499426][ T7153] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 43.504952][ T7153] __tsan_read4+0x2c/0x30 [ 43.509263][ T7153] tcp_poll+0x1cc/0x6b0 [ 43.513403][ T7153] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 43.518854][ T7153] sock_poll+0xed/0x250 [ 43.522989][ T7153] ? sock_read_iter+0x1e0/0x1e0 [ 43.527833][ T7153] ep_item_poll.isra.0+0x90/0x190 [ 43.532850][ T7153] ep_send_events_proc+0x113/0x590 [ 43.537951][ T7153] ? __schedule+0x319/0x640 [ 43.542430][ T7153] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 43.548047][ T7153] ep_scan_ready_list.constprop.0+0x189/0x500 [ 43.554108][ T7153] ? ep_loop_check_proc+0x2f0/0x2f0 [ 43.559303][ T7153] ep_poll+0xe3/0x900 [ 43.563266][ T7153] ? wake_up_q+0x70/0x70 [ 43.567490][ T7153] do_epoll_wait+0x162/0x180 [ 43.572071][ T7153] __x64_sys_epoll_pwait+0xcd/0x180 [ 43.577253][ T7153] do_syscall_64+0xcc/0x370 [ 43.581737][ T7153] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 43.587621][ T7153] RIP: 0033:0x45b300 [ 43.591591][ T7153] 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 [ 43.611343][ T7153] RSP: 002b:000000c42004b860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 43.619729][ T7153] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 43.627708][ T7153] RDX: 0000000000000080 RSI: 000000c42004b8a0 RDI: 0000000000000004 [ 43.635664][ T7153] RBP: 000000c42004bea0 R08: 0000000000000000 R09: 000000c420000900 [ 43.643625][ T7153] R10: 00000000ffffffff R11: 0000000000000246 R12: 000000c420300000 [ 43.651572][ T7153] R13: 000000000000001b R14: 0000000000000000 R15: 0000000000000000 [ 43.660945][ T7153] Kernel Offset: disabled [ 43.665266][ T7153] Rebooting in 86400 seconds..