[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.359034][ T26] audit: type=1800 audit(1571750808.360:25): pid=7050 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.409312][ T26] audit: type=1800 audit(1571750808.370:26): pid=7050 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.433235][ T26] audit: type=1800 audit(1571750808.370:27): pid=7050 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 '10.128.0.168' (ECDSA) to the list of known hosts. 2019/10/22 13:26:56 fuzzer started 2019/10/22 13:26:58 dialing manager at 10.128.0.105:37053 2019/10/22 13:26:58 syscalls: 2524 2019/10/22 13:26:58 code coverage: enabled 2019/10/22 13:26:58 comparison tracing: enabled 2019/10/22 13:26:58 extra coverage: extra coverage is not supported by the kernel 2019/10/22 13:26:58 setuid sandbox: enabled 2019/10/22 13:26:58 namespace sandbox: enabled 2019/10/22 13:26:58 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 13:26:58 fault injection: enabled 2019/10/22 13:26:58 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 13:26:58 net packet injection: enabled 2019/10/22 13:26:58 net device setup: enabled 2019/10/22 13:26:58 concurrency sanitizer: enabled syzkaller login: [ 45.663281][ T7218] ================================================================== [ 45.671513][ T7218] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 45.678520][ T7218] [ 45.680835][ T7218] write to 0xffff888122aaf2f8 of 8 bytes by interrupt on cpu 1: [ 45.688581][ T7218] tcp_add_backlog+0x45a/0xcc0 [ 45.693582][ T7218] tcp_v4_rcv+0x1a60/0x1bb0 [ 45.698064][ T7218] ip_protocol_deliver_rcu+0x4d/0x420 [ 45.703409][ T7218] ip_local_deliver_finish+0x110/0x140 [ 45.708841][ T7218] ip_local_deliver+0x133/0x210 [ 45.713678][ T7218] ip_rcv_finish+0x121/0x160 [ 45.718261][ T7218] ip_rcv+0x18f/0x1a0 [ 45.722231][ T7218] __netif_receive_skb_one_core+0xa7/0xe0 [ 45.727923][ T7218] __netif_receive_skb+0x37/0xf0 [ 45.732837][ T7218] netif_receive_skb_internal+0x59/0x190 [ 45.738445][ T7218] napi_gro_receive+0x28f/0x330 [ 45.743270][ T7218] receive_buf+0x284/0x30b0 [ 45.747755][ T7218] virtnet_poll+0x436/0x7d0 [ 45.752235][ T7218] net_rx_action+0x3ae/0xa90 [ 45.756810][ T7218] [ 45.759133][ T7218] read to 0xffff888122aaf2f8 of 8 bytes by task 7218 on cpu 0: [ 45.766654][ T7218] tcp_recvmsg+0x470/0x1a30 [ 45.771135][ T7218] inet_recvmsg+0xbb/0x250 [ 45.775527][ T7218] sock_recvmsg+0x92/0xb0 [ 45.779848][ T7218] sock_read_iter+0x15f/0x1e0 [ 45.784506][ T7218] new_sync_read+0x389/0x4f0 [ 45.789086][ T7218] __vfs_read+0xb1/0xc0 [ 45.793231][ T7218] vfs_read+0x143/0x2c0 [ 45.797361][ T7218] ksys_read+0xd5/0x1b0 [ 45.801493][ T7218] __x64_sys_read+0x4c/0x60 [ 45.805976][ T7218] do_syscall_64+0xcc/0x370 [ 45.810457][ T7218] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.816331][ T7218] [ 45.818632][ T7218] Reported by Kernel Concurrency Sanitizer on: [ 45.824774][ T7218] CPU: 0 PID: 7218 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.832202][ T7218] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.842229][ T7218] ================================================================== [ 45.850278][ T7218] Kernel panic - not syncing: panic_on_warn set ... [ 45.856843][ T7218] CPU: 0 PID: 7218 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.864285][ T7218] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.874324][ T7218] Call Trace: [ 45.877595][ T7218] dump_stack+0xf5/0x159 [ 45.881817][ T7218] panic+0x210/0x640 [ 45.885703][ T7218] ? __x64_sys_read+0x4c/0x60 [ 45.890377][ T7218] ? vprintk_func+0x8d/0x140 [ 45.894946][ T7218] kcsan_report.cold+0xc/0x10 [ 45.899606][ T7218] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 45.905139][ T7218] __tsan_read8+0x2c/0x30 [ 45.909449][ T7218] tcp_recvmsg+0x470/0x1a30 [ 45.913960][ T7218] inet_recvmsg+0xbb/0x250 [ 45.918351][ T7218] ? __tsan_read8+0x2c/0x30 [ 45.922830][ T7218] ? inet_sendpage+0x100/0x100 [ 45.927584][ T7218] sock_recvmsg+0x92/0xb0 [ 45.931910][ T7218] sock_read_iter+0x15f/0x1e0 [ 45.936572][ T7218] new_sync_read+0x389/0x4f0 [ 45.941145][ T7218] __vfs_read+0xb1/0xc0 [ 45.945278][ T7218] vfs_read+0x143/0x2c0 [ 45.949411][ T7218] ksys_read+0xd5/0x1b0 [ 45.953546][ T7218] __x64_sys_read+0x4c/0x60 [ 45.958044][ T7218] do_syscall_64+0xcc/0x370 [ 45.962586][ T7218] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.968453][ T7218] RIP: 0033:0x47c530 [ 45.972330][ T7218] 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 [ 45.991910][ T7218] RSP: 002b:000000c4202d57d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 46.000296][ T7218] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.008248][ T7218] RDX: 0000000000001000 RSI: 000000c420054000 RDI: 0000000000000003 [ 46.016206][ T7218] RBP: 000000c4202d5830 R08: 0000000000000000 R09: 0000000000000000 [ 46.024154][ T7218] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 46.032116][ T7218] R13: ffffffffffffffff R14: 0000000000000020 R15: ffffffffffffffff [ 46.041507][ T7218] Kernel Offset: disabled [ 46.045864][ T7218] Rebooting in 86400 seconds..