[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.086547][ T25] audit: type=1800 audit(1570191773.105:25): pid=7179 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.106385][ T25] audit: type=1800 audit(1570191773.115:26): pid=7179 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.126482][ T25] audit: type=1800 audit(1570191773.115:27): pid=7179 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 '10.128.0.129' (ECDSA) to the list of known hosts. 2019/10/04 12:23:01 fuzzer started 2019/10/04 12:23:03 dialing manager at 10.128.0.105:38119 2019/10/04 12:23:03 syscalls: 2523 2019/10/04 12:23:03 code coverage: enabled 2019/10/04 12:23:03 comparison tracing: enabled 2019/10/04 12:23:03 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:23:03 setuid sandbox: enabled 2019/10/04 12:23:03 namespace sandbox: enabled 2019/10/04 12:23:03 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:23:03 fault injection: enabled 2019/10/04 12:23:03 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:23:03 net packet injection: enabled 2019/10/04 12:23:03 net device setup: enabled 2019/10/04 12:23:03 concurrency sanitizer: enabled syzkaller login: [ 45.866685][ T7330] ================================================================== [ 45.875102][ T7330] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 45.884639][ T7330] [ 45.887105][ T7330] write to 0xffff8881249cc9f8 of 8 bytes by interrupt on cpu 1: [ 45.894738][ T7330] tcp_add_backlog+0x45a/0xcc0 [ 45.899489][ T7330] tcp_v4_rcv+0x1aba/0x1bf0 [ 45.903975][ T7330] ip_protocol_deliver_rcu+0x51/0x470 [ 45.909326][ T7330] ip_local_deliver_finish+0x110/0x140 [ 45.914771][ T7330] ip_local_deliver+0x133/0x210 [ 45.919609][ T7330] ip_rcv_finish+0x121/0x160 [ 45.924174][ T7330] ip_rcv+0x18f/0x1a0 [ 45.928156][ T7330] __netif_receive_skb_one_core+0xa7/0xe0 [ 45.933991][ T7330] __netif_receive_skb+0x37/0xf0 [ 45.939081][ T7330] netif_receive_skb_internal+0x59/0x190 [ 45.944691][ T7330] napi_gro_receive+0x28f/0x330 [ 45.949545][ T7330] receive_buf+0x284/0x30b0 [ 45.954042][ T7330] virtnet_poll+0x436/0x7d0 [ 45.958525][ T7330] net_rx_action+0x3ae/0xa50 [ 45.963085][ T7330] [ 45.966273][ T7330] read to 0xffff8881249cc9f8 of 8 bytes by task 7330 on cpu 0: [ 45.973808][ T7330] tcp_recvmsg+0x470/0x1a30 [ 45.978321][ T7330] inet_recvmsg+0xbb/0x250 [ 45.982715][ T7330] sock_recvmsg+0x92/0xb0 [ 45.987018][ T7330] sock_read_iter+0x15f/0x1e0 [ 45.991682][ T7330] new_sync_read+0x389/0x4f0 [ 45.996246][ T7330] __vfs_read+0xb1/0xc0 [ 46.000414][ T7330] vfs_read+0x143/0x2c0 [ 46.004554][ T7330] ksys_read+0xd5/0x1b0 [ 46.008686][ T7330] __x64_sys_read+0x4c/0x60 [ 46.013168][ T7330] do_syscall_64+0xcf/0x2f0 [ 46.017649][ T7330] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.023512][ T7330] [ 46.025867][ T7330] Reported by Kernel Concurrency Sanitizer on: [ 46.032004][ T7330] CPU: 0 PID: 7330 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.039083][ T7330] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.049113][ T7330] ================================================================== [ 46.057324][ T7330] Kernel panic - not syncing: panic_on_warn set ... [ 46.063888][ T7330] CPU: 0 PID: 7330 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.070977][ T7330] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.081010][ T7330] Call Trace: [ 46.084289][ T7330] dump_stack+0xf5/0x159 [ 46.088516][ T7330] panic+0x209/0x639 [ 46.092390][ T7330] ? vprintk_func+0x8d/0x140 [ 46.096960][ T7330] kcsan_report.cold+0x57/0xeb [ 46.101706][ T7330] __kcsan_setup_watchpoint+0x342/0x500 [ 46.107238][ T7330] __tsan_read8+0x2c/0x30 [ 46.111557][ T7330] tcp_recvmsg+0x470/0x1a30 [ 46.116057][ T7330] inet_recvmsg+0xbb/0x250 [ 46.120460][ T7330] ? __tsan_read8+0x2c/0x30 [ 46.124944][ T7330] ? inet_sendpage+0x100/0x100 [ 46.129694][ T7330] sock_recvmsg+0x92/0xb0 [ 46.134175][ T7330] sock_read_iter+0x15f/0x1e0 [ 46.138838][ T7330] new_sync_read+0x389/0x4f0 [ 46.143411][ T7330] __vfs_read+0xb1/0xc0 [ 46.148067][ T7330] vfs_read+0x143/0x2c0 [ 46.152210][ T7330] ksys_read+0xd5/0x1b0 [ 46.156343][ T7330] __x64_sys_read+0x4c/0x60 [ 46.160832][ T7330] do_syscall_64+0xcf/0x2f0 [ 46.165349][ T7330] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.171345][ T7330] RIP: 0033:0x47c530 [ 46.175310][ T7330] 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 [ 46.195032][ T7330] RSP: 002b:000000c4202df810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 46.203439][ T7330] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.211509][ T7330] RDX: 0000000000001000 RSI: 000000c420182000 RDI: 0000000000000003 [ 46.221447][ T7330] RBP: 000000c4202df868 R08: 0000000000000000 R09: 0000000000000000 [ 46.229405][ T7330] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 46.237374][ T7330] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 46.246995][ T7330] Kernel Offset: disabled [ 46.251328][ T7330] Rebooting in 86400 seconds..