[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.342041][ T25] audit: type=1800 audit(1570599635.182:25): pid=7074 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 39.379220][ T25] audit: type=1800 audit(1570599635.182:26): pid=7074 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 39.399592][ T25] audit: type=1800 audit(1570599635.182:27): pid=7074 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 '10.128.0.142' (ECDSA) to the list of known hosts. 2019/10/09 05:40:46 fuzzer started 2019/10/09 05:40:48 dialing manager at 10.128.0.105:35069 2019/10/09 05:40:48 syscalls: 2523 2019/10/09 05:40:48 code coverage: enabled 2019/10/09 05:40:48 comparison tracing: enabled 2019/10/09 05:40:48 extra coverage: extra coverage is not supported by the kernel 2019/10/09 05:40:48 setuid sandbox: enabled 2019/10/09 05:40:48 namespace sandbox: enabled 2019/10/09 05:40:48 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/09 05:40:48 fault injection: enabled 2019/10/09 05:40:48 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/09 05:40:48 net packet injection: enabled 2019/10/09 05:40:48 net device setup: enabled 2019/10/09 05:40:48 concurrency sanitizer: enabled syzkaller login: [ 52.710848][ T7239] ================================================================== [ 52.719364][ T7239] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 52.725942][ T7239] [ 52.728264][ T7239] read to 0xffff888126a9ae74 of 4 bytes by task 7226 on cpu 0: [ 52.736387][ T7239] tcp_poll+0x1cc/0x6b0 [ 52.740713][ T7239] sock_poll+0xed/0x250 [ 52.744860][ T7239] ep_item_poll.isra.0+0x90/0x190 [ 52.750055][ T7239] ep_send_events_proc+0x113/0x5c0 [ 52.755194][ T7239] ep_scan_ready_list.constprop.0+0x189/0x500 [ 52.761590][ T7239] ep_poll+0xe3/0x900 [ 52.765580][ T7239] do_epoll_wait+0x162/0x180 [ 52.770173][ T7239] __x64_sys_epoll_pwait+0xcd/0x170 [ 52.775365][ T7239] do_syscall_64+0xcf/0x2f0 [ 52.779889][ T7239] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.785764][ T7239] [ 52.788172][ T7239] write to 0xffff888126a9ae74 of 4 bytes by task 7239 on cpu 1: [ 52.796420][ T7239] tcp_recvmsg+0xd86/0x1a30 [ 52.801010][ T7239] inet_recvmsg+0xbb/0x250 [ 52.805749][ T7239] sock_recvmsg+0x92/0xb0 [ 52.810065][ T7239] sock_read_iter+0x15f/0x1e0 [ 52.814909][ T7239] new_sync_read+0x389/0x4f0 [ 52.819878][ T7239] __vfs_read+0xb1/0xc0 [ 52.824051][ T7239] vfs_read+0x143/0x2c0 [ 52.828317][ T7239] ksys_read+0xd5/0x1b0 [ 52.832723][ T7239] __x64_sys_read+0x4c/0x60 [ 52.837305][ T7239] do_syscall_64+0xcf/0x2f0 [ 52.841808][ T7239] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.847689][ T7239] [ 52.850005][ T7239] Reported by Kernel Concurrency Sanitizer on: [ 52.856236][ T7239] CPU: 1 PID: 7239 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 52.863380][ T7239] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.873632][ T7239] ================================================================== [ 52.881874][ T7239] Kernel panic - not syncing: panic_on_warn set ... [ 52.888552][ T7239] CPU: 1 PID: 7239 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 52.895917][ T7239] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.906641][ T7239] Call Trace: [ 52.909929][ T7239] dump_stack+0xf5/0x159 [ 52.914270][ T7239] panic+0x209/0x639 [ 52.918335][ T7239] ? __x64_sys_read+0x4c/0x60 [ 52.923203][ T7239] ? vprintk_func+0x8d/0x140 [ 52.927872][ T7239] kcsan_report.cold+0xc/0x1b [ 52.932785][ T7239] __kcsan_setup_watchpoint+0x3ee/0x510 [ 52.938479][ T7239] __tsan_write4+0x32/0x40 [ 52.942966][ T7239] tcp_recvmsg+0xd86/0x1a30 [ 52.947475][ T7239] ? __kcsan_setup_watchpoint+0x96/0x510 [ 52.953545][ T7239] inet_recvmsg+0xbb/0x250 [ 52.957955][ T7239] ? __tsan_read8+0x2c/0x30 [ 52.962663][ T7239] ? inet_sendpage+0x100/0x100 [ 52.967419][ T7239] sock_recvmsg+0x92/0xb0 [ 52.971866][ T7239] sock_read_iter+0x15f/0x1e0 [ 52.976628][ T7239] new_sync_read+0x389/0x4f0 [ 52.981232][ T7239] __vfs_read+0xb1/0xc0 [ 52.985499][ T7239] vfs_read+0x143/0x2c0 [ 52.989774][ T7239] ksys_read+0xd5/0x1b0 [ 52.994381][ T7239] __x64_sys_read+0x4c/0x60 [ 52.998965][ T7239] do_syscall_64+0xcf/0x2f0 [ 53.003503][ T7239] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 53.009635][ T7239] RIP: 0033:0x47c530 [ 53.013737][ T7239] 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 [ 53.033809][ T7239] RSP: 002b:000000c42033b810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 53.042351][ T7239] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 53.050488][ T7239] RDX: 0000000000001000 RSI: 000000c42015c000 RDI: 0000000000000003 [ 53.058877][ T7239] RBP: 000000c42033b868 R08: 0000000000000000 R09: 0000000000000000 [ 53.067097][ T7239] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004 [ 53.075097][ T7239] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 53.084742][ T7239] Kernel Offset: disabled [ 53.089076][ T7239] Rebooting in 86400 seconds..