[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.435298][ T26] audit: type=1800 audit(1570192687.894:25): pid=7091 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.455052][ T26] audit: type=1800 audit(1570192687.894:26): pid=7091 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.476752][ T26] audit: type=1800 audit(1570192687.894:27): pid=7091 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 '10.128.15.205' (ECDSA) to the list of known hosts. 2019/10/04 12:38:16 fuzzer started 2019/10/04 12:38:17 dialing manager at 10.128.0.105:38119 2019/10/04 12:38:17 syscalls: 2523 2019/10/04 12:38:17 code coverage: enabled 2019/10/04 12:38:17 comparison tracing: enabled 2019/10/04 12:38:17 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:38:17 setuid sandbox: enabled 2019/10/04 12:38:17 namespace sandbox: enabled 2019/10/04 12:38:17 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:38:17 fault injection: enabled 2019/10/04 12:38:17 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:38:17 net packet injection: enabled 2019/10/04 12:38:17 net device setup: enabled 2019/10/04 12:38:17 concurrency sanitizer: enabled syzkaller login: [ 46.321652][ T7254] ================================================================== [ 46.329907][ T7254] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 46.339263][ T7254] [ 46.341590][ T7254] write to 0xffff8881237e2a38 of 8 bytes by interrupt on cpu 1: [ 46.349343][ T7254] tcp_add_backlog+0x45a/0xcc0 [ 46.354083][ T7254] tcp_v4_rcv+0x1aba/0x1bf0 [ 46.358591][ T7254] ip_protocol_deliver_rcu+0x51/0x470 [ 46.363971][ T7254] ip_local_deliver_finish+0x110/0x140 [ 46.369404][ T7254] ip_local_deliver+0x133/0x210 [ 46.374246][ T7254] ip_rcv_finish+0x121/0x160 [ 46.378808][ T7254] ip_rcv+0x18f/0x1a0 [ 46.382767][ T7254] __netif_receive_skb_one_core+0xa7/0xe0 [ 46.388464][ T7254] __netif_receive_skb+0x37/0xf0 [ 46.393377][ T7254] netif_receive_skb_internal+0x59/0x190 [ 46.398980][ T7254] napi_gro_receive+0x28f/0x330 [ 46.403814][ T7254] receive_buf+0x284/0x30b0 [ 46.408292][ T7254] virtnet_poll+0x436/0x7d0 [ 46.412782][ T7254] net_rx_action+0x3ae/0xa50 [ 46.417343][ T7254] [ 46.419650][ T7254] read to 0xffff8881237e2a38 of 8 bytes by task 7254 on cpu 0: [ 46.427343][ T7254] tcp_recvmsg+0x470/0x1a30 [ 46.431826][ T7254] inet_recvmsg+0xbb/0x250 [ 46.436216][ T7254] sock_recvmsg+0x92/0xb0 [ 46.440516][ T7254] sock_read_iter+0x15f/0x1e0 [ 46.445176][ T7254] new_sync_read+0x389/0x4f0 [ 46.449742][ T7254] __vfs_read+0xb1/0xc0 [ 46.453871][ T7254] vfs_read+0x143/0x2c0 [ 46.458001][ T7254] ksys_read+0xd5/0x1b0 [ 46.462144][ T7254] __x64_sys_read+0x4c/0x60 [ 46.467952][ T7254] do_syscall_64+0xcf/0x2f0 [ 46.472446][ T7254] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.478315][ T7254] [ 46.480632][ T7254] Reported by Kernel Concurrency Sanitizer on: [ 46.486778][ T7254] CPU: 0 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.493861][ T7254] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.503899][ T7254] ================================================================== [ 46.512290][ T7254] Kernel panic - not syncing: panic_on_warn set ... [ 46.519807][ T7254] CPU: 0 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.526890][ T7254] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.537007][ T7254] Call Trace: [ 46.540302][ T7254] dump_stack+0xf5/0x159 [ 46.544541][ T7254] panic+0x209/0x639 [ 46.548455][ T7254] ? vprintk_func+0x8d/0x140 [ 46.553037][ T7254] kcsan_report.cold+0x57/0xeb [ 46.557786][ T7254] __kcsan_setup_watchpoint+0x342/0x500 [ 46.563311][ T7254] __tsan_read8+0x2c/0x30 [ 46.567629][ T7254] tcp_recvmsg+0x470/0x1a30 [ 46.572118][ T7254] inet_recvmsg+0xbb/0x250 [ 46.576531][ T7254] ? __tsan_read8+0x2c/0x30 [ 46.581014][ T7254] ? inet_sendpage+0x100/0x100 [ 46.585759][ T7254] sock_recvmsg+0x92/0xb0 [ 46.590066][ T7254] sock_read_iter+0x15f/0x1e0 [ 46.594740][ T7254] new_sync_read+0x389/0x4f0 [ 46.599574][ T7254] __vfs_read+0xb1/0xc0 [ 46.603711][ T7254] vfs_read+0x143/0x2c0 [ 46.607855][ T7254] ksys_read+0xd5/0x1b0 [ 46.611998][ T7254] __x64_sys_read+0x4c/0x60 [ 46.616491][ T7254] do_syscall_64+0xcf/0x2f0 [ 46.620979][ T7254] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.626852][ T7254] RIP: 0033:0x47c530 [ 46.630727][ T7254] 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 [ 46.650307][ T7254] RSP: 002b:000000c4202e57d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 46.658739][ T7254] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.666738][ T7254] RDX: 0000000000001000 RSI: 000000c42015e000 RDI: 0000000000000003 [ 46.674695][ T7254] RBP: 000000c4202e5830 R08: 0000000000000000 R09: 0000000000000000 [ 46.682655][ T7254] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000040 [ 46.690611][ T7254] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 46.699967][ T7254] Kernel Offset: disabled [ 46.704295][ T7254] Rebooting in 86400 seconds..