[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 33.251318][ T25] audit: type=1800 audit(1570192334.603:25): pid=7011 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 33.278176][ T25] audit: type=1800 audit(1570192334.613:26): pid=7011 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 33.311378][ T25] audit: type=1800 audit(1570192334.613:27): pid=7011 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 '10.128.1.58' (ECDSA) to the list of known hosts. 2019/10/04 12:32:37 fuzzer started 2019/10/04 12:32:38 dialing manager at 10.128.0.105:38119 2019/10/04 12:32:38 syscalls: 2523 2019/10/04 12:32:38 code coverage: enabled 2019/10/04 12:32:38 comparison tracing: enabled 2019/10/04 12:32:38 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:32:38 setuid sandbox: enabled 2019/10/04 12:32:38 namespace sandbox: enabled 2019/10/04 12:32:38 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:32:38 fault injection: enabled 2019/10/04 12:32:38 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:32:38 net packet injection: enabled 2019/10/04 12:32:38 net device setup: enabled 2019/10/04 12:32:38 concurrency sanitizer: enabled syzkaller login: [ 58.017040][ T7165] ================================================================== [ 58.025280][ T7165] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 58.034623][ T7165] [ 58.036926][ T7165] write to 0xffff8881220269f8 of 8 bytes by interrupt on cpu 0: [ 58.044527][ T7165] tcp_add_backlog+0x45a/0xcc0 [ 58.049269][ T7165] tcp_v4_rcv+0x1aba/0x1bf0 [ 58.053743][ T7165] ip_protocol_deliver_rcu+0x51/0x470 [ 58.059096][ T7165] ip_local_deliver_finish+0x110/0x140 [ 58.064553][ T7165] ip_local_deliver+0x133/0x210 [ 58.069396][ T7165] ip_rcv_finish+0x121/0x160 [ 58.073966][ T7165] ip_rcv+0x18f/0x1a0 [ 58.077924][ T7165] __netif_receive_skb_one_core+0xa7/0xe0 [ 58.083668][ T7165] __netif_receive_skb+0x37/0xf0 [ 58.088582][ T7165] netif_receive_skb_internal+0x59/0x190 [ 58.094185][ T7165] napi_gro_receive+0x28f/0x330 [ 58.099025][ T7165] receive_buf+0x284/0x30b0 [ 58.103500][ T7165] virtnet_poll+0x436/0x7d0 [ 58.108007][ T7165] net_rx_action+0x3ae/0xa50 [ 58.112563][ T7165] [ 58.114864][ T7165] read to 0xffff8881220269f8 of 8 bytes by task 7165 on cpu 1: [ 58.122415][ T7165] tcp_recvmsg+0x470/0x1a30 [ 58.126891][ T7165] inet_recvmsg+0xbb/0x250 [ 58.131289][ T7165] sock_recvmsg+0x92/0xb0 [ 58.135591][ T7165] sock_read_iter+0x15f/0x1e0 [ 58.140303][ T7165] new_sync_read+0x389/0x4f0 [ 58.144866][ T7165] __vfs_read+0xb1/0xc0 [ 58.149007][ T7165] vfs_read+0x143/0x2c0 [ 58.153152][ T7165] ksys_read+0xd5/0x1b0 [ 58.157310][ T7165] __x64_sys_read+0x4c/0x60 [ 58.161787][ T7165] do_syscall_64+0xcf/0x2f0 [ 58.166265][ T7165] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 58.172119][ T7165] [ 58.174417][ T7165] Reported by Kernel Concurrency Sanitizer on: [ 58.180545][ T7165] CPU: 1 PID: 7165 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 58.187619][ T7165] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.197657][ T7165] ================================================================== [ 58.205688][ T7165] Kernel panic - not syncing: panic_on_warn set ... [ 58.212255][ T7165] CPU: 1 PID: 7165 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 58.219361][ T7165] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.229386][ T7165] Call Trace: [ 58.232651][ T7165] dump_stack+0xf5/0x159 [ 58.236864][ T7165] panic+0x209/0x639 [ 58.240734][ T7165] ? vprintk_func+0x8d/0x140 [ 58.245300][ T7165] kcsan_report.cold+0x57/0xeb [ 58.250052][ T7165] __kcsan_setup_watchpoint+0x342/0x500 [ 58.255572][ T7165] __tsan_read8+0x2c/0x30 [ 58.259884][ T7165] tcp_recvmsg+0x470/0x1a30 [ 58.264362][ T7165] inet_recvmsg+0xbb/0x250 [ 58.268748][ T7165] ? __tsan_read8+0x2c/0x30 [ 58.273322][ T7165] ? inet_sendpage+0x100/0x100 [ 58.278072][ T7165] sock_recvmsg+0x92/0xb0 [ 58.282388][ T7165] sock_read_iter+0x15f/0x1e0 [ 58.287039][ T7165] new_sync_read+0x389/0x4f0 [ 58.291606][ T7165] __vfs_read+0xb1/0xc0 [ 58.295735][ T7165] vfs_read+0x143/0x2c0 [ 58.299892][ T7165] ksys_read+0xd5/0x1b0 [ 58.304034][ T7165] __x64_sys_read+0x4c/0x60 [ 58.308523][ T7165] do_syscall_64+0xcf/0x2f0 [ 58.313037][ T7165] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 58.318901][ T7165] RIP: 0033:0x47c530 [ 58.322775][ T7165] 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 [ 58.342355][ T7165] RSP: 002b:000000c4204fd7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 58.350740][ T7165] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 58.358685][ T7165] RDX: 0000000000001000 RSI: 000000c420384000 RDI: 0000000000000003 [ 58.366631][ T7165] RBP: 000000c4204fd830 R08: 0000000000000000 R09: 0000000000000000 [ 58.374574][ T7165] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000100 [ 58.382514][ T7165] R13: ffffffffffffffff R14: 0000000000000020 R15: ffffffffffffffff [ 58.391776][ T7165] Kernel Offset: disabled [ 58.396096][ T7165] Rebooting in 86400 seconds..