[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.224821][ T26] audit: type=1800 audit(1571747010.027:25): pid=6957 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.269832][ T26] audit: type=1800 audit(1571747010.027:26): pid=6957 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.293317][ T26] audit: type=1800 audit(1571747010.027:27): pid=6957 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 '10.128.0.235' (ECDSA) to the list of known hosts. 2019/10/22 12:23:41 fuzzer started 2019/10/22 12:23:42 dialing manager at 10.128.0.105:37053 2019/10/22 12:23:42 syscalls: 2524 2019/10/22 12:23:42 code coverage: enabled 2019/10/22 12:23:42 comparison tracing: enabled 2019/10/22 12:23:42 extra coverage: extra coverage is not supported by the kernel 2019/10/22 12:23:42 setuid sandbox: enabled 2019/10/22 12:23:42 namespace sandbox: enabled 2019/10/22 12:23:42 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 12:23:42 fault injection: enabled 2019/10/22 12:23:42 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 12:23:42 net packet injection: enabled 2019/10/22 12:23:42 net device setup: enabled 2019/10/22 12:23:42 concurrency sanitizer: enabled syzkaller login: [ 48.039084][ T7112] ================================================================== [ 48.047231][ T7112] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 48.053790][ T7112] [ 48.056115][ T7112] read to 0xffff8881236177bc of 4 bytes by task 7108 on cpu 1: [ 48.063647][ T7112] tcp_poll+0x1cc/0x6b0 [ 48.067929][ T7112] sock_poll+0xed/0x250 [ 48.072075][ T7112] ep_item_poll.isra.0+0x90/0x190 [ 48.077172][ T7112] ep_send_events_proc+0x113/0x590 [ 48.082328][ T7112] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.088380][ T7112] ep_poll+0xe3/0x900 [ 48.092357][ T7112] do_epoll_wait+0x162/0x180 [ 48.096935][ T7112] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.102141][ T7112] do_syscall_64+0xcc/0x370 [ 48.106689][ T7112] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.112709][ T7112] [ 48.115028][ T7112] write to 0xffff8881236177bc of 4 bytes by task 7112 on cpu 0: [ 48.122647][ T7112] tcp_recvmsg+0xd86/0x1a30 [ 48.127141][ T7112] inet_recvmsg+0xbb/0x250 [ 48.131548][ T7112] sock_recvmsg+0x92/0xb0 [ 48.135914][ T7112] sock_read_iter+0x15f/0x1e0 [ 48.140579][ T7112] new_sync_read+0x389/0x4f0 [ 48.145156][ T7112] __vfs_read+0xb1/0xc0 [ 48.149307][ T7112] vfs_read+0x143/0x2c0 [ 48.153449][ T7112] ksys_read+0xd5/0x1b0 [ 48.157590][ T7112] __x64_sys_read+0x4c/0x60 [ 48.162094][ T7112] do_syscall_64+0xcc/0x370 [ 48.166585][ T7112] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.172458][ T7112] [ 48.174772][ T7112] Reported by Kernel Concurrency Sanitizer on: [ 48.180914][ T7112] CPU: 0 PID: 7112 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.188469][ T7112] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.198512][ T7112] ================================================================== [ 48.206561][ T7112] Kernel panic - not syncing: panic_on_warn set ... [ 48.213149][ T7112] CPU: 0 PID: 7112 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.220621][ T7112] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.230664][ T7112] Call Trace: [ 48.233995][ T7112] dump_stack+0xf5/0x159 [ 48.238242][ T7112] panic+0x210/0x640 [ 48.242268][ T7112] ? __x64_sys_read+0x4c/0x60 [ 48.246933][ T7112] ? vprintk_func+0x8d/0x140 [ 48.251514][ T7112] kcsan_report.cold+0xc/0x10 [ 48.256191][ T7112] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.261724][ T7112] __tsan_write4+0x32/0x40 [ 48.266140][ T7112] tcp_recvmsg+0xd86/0x1a30 [ 48.270740][ T7112] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.276364][ T7112] inet_recvmsg+0xbb/0x250 [ 48.280769][ T7112] ? __tsan_read8+0x2c/0x30 [ 48.285260][ T7112] ? inet_sendpage+0x100/0x100 [ 48.290013][ T7112] sock_recvmsg+0x92/0xb0 [ 48.294333][ T7112] sock_read_iter+0x15f/0x1e0 [ 48.299029][ T7112] new_sync_read+0x389/0x4f0 [ 48.303615][ T7112] __vfs_read+0xb1/0xc0 [ 48.307759][ T7112] vfs_read+0x143/0x2c0 [ 48.311913][ T7112] ksys_read+0xd5/0x1b0 [ 48.316267][ T7112] __x64_sys_read+0x4c/0x60 [ 48.320774][ T7112] do_syscall_64+0xcc/0x370 [ 48.325407][ T7112] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.331451][ T7112] RIP: 0033:0x47c530 [ 48.335342][ T7112] 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 [ 48.355139][ T7112] RSP: 002b:000000c4202d17d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 48.363646][ T7112] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.371641][ T7112] RDX: 0000000000001000 RSI: 000000c4200a6000 RDI: 0000000000000003 [ 48.379621][ T7112] RBP: 000000c4202d1830 R08: 0000000000000000 R09: 0000000000000000 [ 48.387587][ T7112] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000040 [ 48.395806][ T7112] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 48.406447][ T7112] Kernel Offset: disabled [ 48.410823][ T7112] Rebooting in 86400 seconds..