[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 38.154675][ T26] audit: type=1800 audit(1571745269.790:25): pid=7096 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 38.199955][ T26] audit: type=1800 audit(1571745269.790:26): pid=7096 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 38.221156][ T26] audit: type=1800 audit(1571745269.800:27): pid=7096 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 '10.128.0.60' (ECDSA) to the list of known hosts. 2019/10/22 11:54:38 fuzzer started 2019/10/22 11:54:41 dialing manager at 10.128.0.105:37053 2019/10/22 11:54:41 syscalls: 2524 2019/10/22 11:54:41 code coverage: enabled 2019/10/22 11:54:41 comparison tracing: enabled 2019/10/22 11:54:41 extra coverage: extra coverage is not supported by the kernel 2019/10/22 11:54:41 setuid sandbox: enabled 2019/10/22 11:54:41 namespace sandbox: enabled 2019/10/22 11:54:41 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 11:54:41 fault injection: enabled 2019/10/22 11:54:41 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 11:54:41 net packet injection: enabled 2019/10/22 11:54:41 net device setup: enabled 2019/10/22 11:54:41 concurrency sanitizer: enabled syzkaller login: [ 49.940412][ T7256] ================================================================== [ 49.948806][ T7256] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 49.955813][ T7256] [ 49.958130][ T7256] write to 0xffff888126a189f8 of 8 bytes by interrupt on cpu 1: [ 49.965941][ T7256] tcp_add_backlog+0x45a/0xcc0 [ 49.970860][ T7256] tcp_v4_rcv+0x1a60/0x1bb0 [ 49.975410][ T7256] ip_protocol_deliver_rcu+0x4d/0x420 [ 49.980881][ T7256] ip_local_deliver_finish+0x110/0x140 [ 49.986647][ T7256] ip_local_deliver+0x133/0x210 [ 49.991500][ T7256] ip_rcv_finish+0x121/0x160 [ 49.996529][ T7256] ip_rcv+0x18f/0x1a0 [ 50.000991][ T7256] __netif_receive_skb_one_core+0xa7/0xe0 [ 50.006952][ T7256] __netif_receive_skb+0x37/0xf0 [ 50.012381][ T7256] netif_receive_skb_internal+0x59/0x190 [ 50.018027][ T7256] napi_gro_receive+0x28f/0x330 [ 50.022974][ T7256] receive_buf+0x284/0x30b0 [ 50.027457][ T7256] virtnet_poll+0x436/0x7d0 [ 50.032218][ T7256] net_rx_action+0x3ae/0xa90 [ 50.037083][ T7256] [ 50.039412][ T7256] read to 0xffff888126a189f8 of 8 bytes by task 7256 on cpu 0: [ 50.047144][ T7256] tcp_recvmsg+0x470/0x1a30 [ 50.051650][ T7256] inet_recvmsg+0xbb/0x250 [ 50.056060][ T7256] sock_recvmsg+0x92/0xb0 [ 50.060377][ T7256] sock_read_iter+0x15f/0x1e0 [ 50.066306][ T7256] new_sync_read+0x389/0x4f0 [ 50.070883][ T7256] __vfs_read+0xb1/0xc0 [ 50.075510][ T7256] vfs_read+0x143/0x2c0 [ 50.079923][ T7256] ksys_read+0xd5/0x1b0 [ 50.084187][ T7256] __x64_sys_read+0x4c/0x60 [ 50.088691][ T7256] do_syscall_64+0xcc/0x370 [ 50.093550][ T7256] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.099535][ T7256] [ 50.101863][ T7256] Reported by Kernel Concurrency Sanitizer on: [ 50.108560][ T7256] CPU: 0 PID: 7256 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.116325][ T7256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.126900][ T7256] ================================================================== [ 50.135162][ T7256] Kernel panic - not syncing: panic_on_warn set ... [ 50.142126][ T7256] CPU: 0 PID: 7256 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.149677][ T7256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.159830][ T7256] Call Trace: [ 50.163120][ T7256] dump_stack+0xf5/0x159 [ 50.167354][ T7256] panic+0x210/0x640 [ 50.171348][ T7256] ? __x64_sys_read+0x4c/0x60 [ 50.176112][ T7256] ? vprintk_func+0x8d/0x140 [ 50.181571][ T7256] kcsan_report.cold+0xc/0x10 [ 50.186388][ T7256] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 50.191958][ T7256] __tsan_read8+0x2c/0x30 [ 50.196710][ T7256] tcp_recvmsg+0x470/0x1a30 [ 50.201564][ T7256] inet_recvmsg+0xbb/0x250 [ 50.206100][ T7256] ? __tsan_read8+0x2c/0x30 [ 50.210591][ T7256] ? inet_sendpage+0x100/0x100 [ 50.215569][ T7256] sock_recvmsg+0x92/0xb0 [ 50.220043][ T7256] sock_read_iter+0x15f/0x1e0 [ 50.224865][ T7256] new_sync_read+0x389/0x4f0 [ 50.229514][ T7256] __vfs_read+0xb1/0xc0 [ 50.233666][ T7256] vfs_read+0x143/0x2c0 [ 50.238187][ T7256] ksys_read+0xd5/0x1b0 [ 50.242684][ T7256] __x64_sys_read+0x4c/0x60 [ 50.247182][ T7256] do_syscall_64+0xcc/0x370 [ 50.252140][ T7256] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.258221][ T7256] RIP: 0033:0x47c530 [ 50.262125][ T7256] 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 [ 50.282318][ T7256] RSP: 002b:000000c4203c17d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 50.290891][ T7256] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.298868][ T7256] RDX: 0000000000001000 RSI: 000000c420378000 RDI: 0000000000000003 [ 50.306961][ T7256] RBP: 000000c4203c1830 R08: 0000000000000000 R09: 0000000000000000 [ 50.315089][ T7256] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 50.323043][ T7256] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 50.333046][ T7256] Kernel Offset: disabled [ 50.337418][ T7256] Rebooting in 86400 seconds..