[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.956051][ T25] audit: type=1800 audit(1570849322.255:25): pid=7076 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.983236][ T25] audit: type=1800 audit(1570849322.255:26): pid=7076 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.015825][ T25] audit: type=1800 audit(1570849322.255:27): pid=7076 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 '10.128.0.32' (ECDSA) to the list of known hosts. 2019/10/12 03:02:11 fuzzer started 2019/10/12 03:02:12 dialing manager at 10.128.0.105:43913 2019/10/12 03:02:12 syscalls: 2523 2019/10/12 03:02:12 code coverage: enabled 2019/10/12 03:02:12 comparison tracing: enabled 2019/10/12 03:02:12 extra coverage: extra coverage is not supported by the kernel 2019/10/12 03:02:12 setuid sandbox: enabled 2019/10/12 03:02:12 namespace sandbox: enabled 2019/10/12 03:02:12 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/12 03:02:12 fault injection: enabled 2019/10/12 03:02:12 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/12 03:02:12 net packet injection: enabled 2019/10/12 03:02:12 net device setup: enabled 2019/10/12 03:02:12 concurrency sanitizer: enabled syzkaller login: [ 46.827778][ T7231] ================================================================== [ 46.835915][ T7231] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 46.842333][ T7231] [ 46.844689][ T7231] read to 0xffff888126562e74 of 4 bytes by task 7229 on cpu 1: [ 46.852217][ T7231] tcp_poll+0x1cc/0x6b0 [ 46.856358][ T7231] sock_poll+0xed/0x250 [ 46.860494][ T7231] ep_item_poll.isra.0+0x90/0x190 [ 46.865513][ T7231] ep_send_events_proc+0x113/0x5c0 [ 46.870606][ T7231] ep_scan_ready_list.constprop.0+0x189/0x500 [ 46.876679][ T7231] ep_poll+0xe3/0x900 [ 46.880646][ T7231] do_epoll_wait+0x162/0x180 [ 46.885218][ T7231] __x64_sys_epoll_pwait+0xcd/0x170 [ 46.891104][ T7231] do_syscall_64+0xcf/0x2f0 [ 46.895594][ T7231] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.901487][ T7231] [ 46.903800][ T7231] write to 0xffff888126562e74 of 4 bytes by task 7231 on cpu 0: [ 46.911408][ T7231] tcp_recvmsg+0xd86/0x1a30 [ 46.915891][ T7231] inet_recvmsg+0xbb/0x250 [ 46.920287][ T7231] sock_recvmsg+0x92/0xb0 [ 46.924594][ T7231] sock_read_iter+0x15f/0x1e0 [ 46.929558][ T7231] new_sync_read+0x389/0x4f0 [ 46.934128][ T7231] __vfs_read+0xb1/0xc0 [ 46.938263][ T7231] vfs_read+0x143/0x2c0 [ 46.942398][ T7231] ksys_read+0xd5/0x1b0 [ 46.946652][ T7231] __x64_sys_read+0x4c/0x60 [ 46.951135][ T7231] do_syscall_64+0xcf/0x2f0 [ 46.955631][ T7231] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.961506][ T7231] [ 46.963815][ T7231] Reported by Kernel Concurrency Sanitizer on: [ 46.969954][ T7231] CPU: 0 PID: 7231 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.977071][ T7231] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.987108][ T7231] ================================================================== [ 46.995144][ T7231] Kernel panic - not syncing: panic_on_warn set ... [ 47.001710][ T7231] CPU: 0 PID: 7231 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.008793][ T7231] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.018836][ T7231] Call Trace: [ 47.022201][ T7231] dump_stack+0xf5/0x159 [ 47.026911][ T7231] panic+0x209/0x639 [ 47.030801][ T7231] ? __x64_sys_read+0x4c/0x60 [ 47.035715][ T7231] ? vprintk_func+0x8d/0x140 [ 47.040350][ T7231] kcsan_report.cold+0xc/0x1b [ 47.045103][ T7231] __kcsan_setup_watchpoint+0x3ee/0x510 [ 47.050663][ T7231] __tsan_write4+0x32/0x40 [ 47.055065][ T7231] tcp_recvmsg+0xd86/0x1a30 [ 47.059567][ T7231] ? __kcsan_setup_watchpoint+0x96/0x510 [ 47.065182][ T7231] inet_recvmsg+0xbb/0x250 [ 47.069575][ T7231] ? __tsan_read8+0x2c/0x30 [ 47.074062][ T7231] ? inet_sendpage+0x100/0x100 [ 47.078810][ T7231] sock_recvmsg+0x92/0xb0 [ 47.083156][ T7231] sock_read_iter+0x15f/0x1e0 [ 47.087817][ T7231] new_sync_read+0x389/0x4f0 [ 47.092400][ T7231] __vfs_read+0xb1/0xc0 [ 47.096539][ T7231] vfs_read+0x143/0x2c0 [ 47.100677][ T7231] ksys_read+0xd5/0x1b0 [ 47.104828][ T7231] __x64_sys_read+0x4c/0x60 [ 47.109325][ T7231] do_syscall_64+0xcf/0x2f0 [ 47.113898][ T7231] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.119770][ T7231] RIP: 0033:0x47c530 [ 47.123659][ T7231] 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 [ 47.143260][ T7231] RSP: 002b:000000c4203a1810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 47.151672][ T7231] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 47.159639][ T7231] RDX: 0000000000001000 RSI: 000000c4203ba000 RDI: 0000000000000003 [ 47.167593][ T7231] RBP: 000000c4203a1868 R08: 0000000000000000 R09: 0000000000000000 [ 47.175545][ T7231] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000010 [ 47.183617][ T7231] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 47.193117][ T7231] Kernel Offset: disabled [ 47.197444][ T7231] Rebooting in 86400 seconds..