[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.422184][ T25] audit: type=1800 audit(1570192557.618:25): pid=7104 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.442105][ T25] audit: type=1800 audit(1570192557.618:26): pid=7104 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.463990][ T25] audit: type=1800 audit(1570192557.618:27): pid=7104 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 '10.128.0.122' (ECDSA) to the list of known hosts. 2019/10/04 12:36:20 fuzzer started 2019/10/04 12:36:22 dialing manager at 10.128.0.105:38119 2019/10/04 12:36:22 syscalls: 2523 2019/10/04 12:36:22 code coverage: enabled 2019/10/04 12:36:22 comparison tracing: enabled 2019/10/04 12:36:22 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:36:22 setuid sandbox: enabled 2019/10/04 12:36:22 namespace sandbox: enabled 2019/10/04 12:36:22 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:36:22 fault injection: enabled 2019/10/04 12:36:22 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:36:22 net packet injection: enabled 2019/10/04 12:36:22 net device setup: enabled 2019/10/04 12:36:22 concurrency sanitizer: enabled syzkaller login: [ 62.013326][ T7263] ================================================================== [ 62.021588][ T7263] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 62.031046][ T7263] [ 62.033381][ T7263] write to 0xffff8881264fa9f8 of 8 bytes by interrupt on cpu 1: [ 62.041136][ T7263] tcp_add_backlog+0x45a/0xcc0 [ 62.045880][ T7263] tcp_v4_rcv+0x1aba/0x1bf0 [ 62.050411][ T7263] ip_protocol_deliver_rcu+0x51/0x470 [ 62.056204][ T7263] ip_local_deliver_finish+0x110/0x140 [ 62.061652][ T7263] ip_local_deliver+0x133/0x210 [ 62.066488][ T7263] ip_rcv_finish+0x121/0x160 [ 62.071053][ T7263] ip_rcv+0x18f/0x1a0 [ 62.075029][ T7263] __netif_receive_skb_one_core+0xa7/0xe0 [ 62.080996][ T7263] __netif_receive_skb+0x37/0xf0 [ 62.085920][ T7263] netif_receive_skb_internal+0x59/0x190 [ 62.091637][ T7263] napi_gro_receive+0x28f/0x330 [ 62.096492][ T7263] receive_buf+0x284/0x30b0 [ 62.100972][ T7263] virtnet_poll+0x436/0x7d0 [ 62.105454][ T7263] net_rx_action+0x3ae/0xa50 [ 62.110029][ T7263] [ 62.112352][ T7263] read to 0xffff8881264fa9f8 of 8 bytes by task 7263 on cpu 0: [ 62.119958][ T7263] tcp_recvmsg+0x470/0x1a30 [ 62.124482][ T7263] inet_recvmsg+0xbb/0x250 [ 62.129091][ T7263] sock_recvmsg+0x92/0xb0 [ 62.133398][ T7263] sock_read_iter+0x15f/0x1e0 [ 62.138142][ T7263] new_sync_read+0x389/0x4f0 [ 62.142899][ T7263] __vfs_read+0xb1/0xc0 [ 62.147044][ T7263] vfs_read+0x143/0x2c0 [ 62.151176][ T7263] ksys_read+0xd5/0x1b0 [ 62.155310][ T7263] __x64_sys_read+0x4c/0x60 [ 62.159879][ T7263] do_syscall_64+0xcf/0x2f0 [ 62.164464][ T7263] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.170326][ T7263] [ 62.172642][ T7263] Reported by Kernel Concurrency Sanitizer on: [ 62.178775][ T7263] CPU: 0 PID: 7263 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 62.185874][ T7263] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.195909][ T7263] ================================================================== [ 62.204050][ T7263] Kernel panic - not syncing: panic_on_warn set ... [ 62.210619][ T7263] CPU: 0 PID: 7263 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 62.217711][ T7263] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.227753][ T7263] Call Trace: [ 62.231047][ T7263] dump_stack+0xf5/0x159 [ 62.235289][ T7263] panic+0x209/0x639 [ 62.239171][ T7263] ? vprintk_func+0x8d/0x140 [ 62.243759][ T7263] kcsan_report.cold+0x57/0xeb [ 62.248510][ T7263] __kcsan_setup_watchpoint+0x342/0x500 [ 62.254080][ T7263] __tsan_read8+0x2c/0x30 [ 62.258413][ T7263] tcp_recvmsg+0x470/0x1a30 [ 62.262906][ T7263] inet_recvmsg+0xbb/0x250 [ 62.267312][ T7263] ? __tsan_read8+0x2c/0x30 [ 62.271797][ T7263] ? inet_sendpage+0x100/0x100 [ 62.276552][ T7263] sock_recvmsg+0x92/0xb0 [ 62.280898][ T7263] sock_read_iter+0x15f/0x1e0 [ 62.285575][ T7263] new_sync_read+0x389/0x4f0 [ 62.290171][ T7263] __vfs_read+0xb1/0xc0 [ 62.294327][ T7263] vfs_read+0x143/0x2c0 [ 62.298473][ T7263] ksys_read+0xd5/0x1b0 [ 62.302715][ T7263] __x64_sys_read+0x4c/0x60 [ 62.307301][ T7263] do_syscall_64+0xcf/0x2f0 [ 62.311851][ T7263] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.317760][ T7263] RIP: 0033:0x47c530 [ 62.321838][ T7263] 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 [ 62.342310][ T7263] RSP: 002b:000000c4204f97d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 62.350722][ T7263] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 62.358695][ T7263] RDX: 0000000000001000 RSI: 000000c420058000 RDI: 0000000000000003 [ 62.366650][ T7263] RBP: 000000c4204f9830 R08: 0000000000000000 R09: 0000000000000000 [ 62.374722][ T7263] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 62.382694][ T7263] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 62.392064][ T7263] Kernel Offset: disabled [ 62.396477][ T7263] Rebooting in 86400 seconds..