[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.131941][ T26] audit: type=1800 audit(1570946523.313:25): pid=7025 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.179128][ T26] audit: type=1800 audit(1570946523.313:26): pid=7025 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.200902][ T26] audit: type=1800 audit(1570946523.313:27): pid=7025 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 '10.128.0.32' (ECDSA) to the list of known hosts. 2019/10/13 06:02:10 fuzzer started 2019/10/13 06:02:12 dialing manager at 10.128.0.105:43913 2019/10/13 06:02:12 syscalls: 2523 2019/10/13 06:02:12 code coverage: enabled 2019/10/13 06:02:12 comparison tracing: enabled 2019/10/13 06:02:12 extra coverage: extra coverage is not supported by the kernel 2019/10/13 06:02:12 setuid sandbox: enabled 2019/10/13 06:02:12 namespace sandbox: enabled 2019/10/13 06:02:12 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/13 06:02:12 fault injection: enabled 2019/10/13 06:02:12 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/13 06:02:12 net packet injection: enabled 2019/10/13 06:02:12 net device setup: enabled 2019/10/13 06:02:12 concurrency sanitizer: enabled syzkaller login: [ 44.085288][ T7187] ================================================================== [ 44.093717][ T7187] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 44.101581][ T7187] [ 44.104005][ T7187] read to 0xffff88812649414c of 4 bytes by interrupt on cpu 0: [ 44.111535][ T7187] tcp_add_backlog+0x43/0xcc0 [ 44.116386][ T7187] tcp_v4_rcv+0x1aba/0x1bf0 [ 44.120891][ T7187] ip_protocol_deliver_rcu+0x51/0x470 [ 44.126325][ T7187] ip_local_deliver_finish+0x110/0x140 [ 44.131758][ T7187] ip_local_deliver+0x133/0x210 [ 44.136592][ T7187] ip_rcv_finish+0x121/0x160 [ 44.141160][ T7187] ip_rcv+0x18f/0x1a0 [ 44.145120][ T7187] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.152305][ T7187] __netif_receive_skb+0x37/0xf0 [ 44.157334][ T7187] netif_receive_skb_internal+0x59/0x190 [ 44.162943][ T7187] napi_gro_receive+0x28f/0x330 [ 44.167783][ T7187] receive_buf+0x284/0x30b0 [ 44.172264][ T7187] virtnet_poll+0x436/0x7d0 [ 44.176750][ T7187] net_rx_action+0x3ae/0xa50 [ 44.181308][ T7187] [ 44.183617][ T7187] write to 0xffff88812649414c of 4 bytes by task 7187 on cpu 1: [ 44.191244][ T7187] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.196419][ T7187] tcp_recvmsg+0xdaa/0x1a30 [ 44.200903][ T7187] inet_recvmsg+0xbb/0x250 [ 44.205295][ T7187] sock_recvmsg+0x92/0xb0 [ 44.209613][ T7187] sock_read_iter+0x15f/0x1e0 [ 44.214266][ T7187] new_sync_read+0x389/0x4f0 [ 44.218830][ T7187] __vfs_read+0xb1/0xc0 [ 44.222961][ T7187] vfs_read+0x143/0x2c0 [ 44.227104][ T7187] ksys_read+0xd5/0x1b0 [ 44.231256][ T7187] __x64_sys_read+0x4c/0x60 [ 44.235733][ T7187] do_syscall_64+0xcf/0x2f0 [ 44.240228][ T7187] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.246084][ T7187] [ 44.248404][ T7187] Reported by Kernel Concurrency Sanitizer on: [ 44.254530][ T7187] CPU: 1 PID: 7187 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 44.261695][ T7187] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.271723][ T7187] ================================================================== [ 44.279760][ T7187] Kernel panic - not syncing: panic_on_warn set ... [ 44.287302][ T7187] CPU: 1 PID: 7187 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 44.294379][ T7187] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.304408][ T7187] Call Trace: [ 44.307679][ T7187] dump_stack+0xf5/0x159 [ 44.311902][ T7187] panic+0x209/0x639 [ 44.315779][ T7187] ? ksys_read+0xd5/0x1b0 [ 44.321321][ T7187] ? vprintk_func+0x8d/0x140 [ 44.325891][ T7187] kcsan_report.cold+0xc/0x1b [ 44.330547][ T7187] __kcsan_setup_watchpoint+0x3ee/0x510 [ 44.336082][ T7187] __tsan_write4+0x32/0x40 [ 44.340480][ T7187] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.345670][ T7187] tcp_recvmsg+0xdaa/0x1a30 [ 44.350155][ T7187] ? __kcsan_setup_watchpoint+0x96/0x510 [ 44.356319][ T7187] inet_recvmsg+0xbb/0x250 [ 44.361409][ T7187] ? __tsan_read8+0x2c/0x30 [ 44.367568][ T7187] ? inet_sendpage+0x100/0x100 [ 44.372417][ T7187] sock_recvmsg+0x92/0xb0 [ 44.377523][ T7187] sock_read_iter+0x15f/0x1e0 [ 44.382666][ T7187] new_sync_read+0x389/0x4f0 [ 44.388313][ T7187] __vfs_read+0xb1/0xc0 [ 44.393029][ T7187] vfs_read+0x143/0x2c0 [ 44.398499][ T7187] ksys_read+0xd5/0x1b0 [ 44.402915][ T7187] __x64_sys_read+0x4c/0x60 [ 44.407609][ T7187] do_syscall_64+0xcf/0x2f0 [ 44.412272][ T7187] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.418880][ T7187] RIP: 0033:0x47c530 [ 44.422875][ T7187] 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 [ 44.443179][ T7187] RSP: 002b:000000c4204e58b8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 44.452801][ T7187] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.461662][ T7187] RDX: 0000000000001000 RSI: 000000c42037a000 RDI: 0000000000000003 [ 44.470837][ T7187] RBP: 000000c4204e5910 R08: 0000000000000000 R09: 0000000000000000 [ 44.480740][ T7187] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000800 [ 44.488688][ T7187] R13: 000000000000000f R14: 00007ff8070d16c8 R15: 0000000000000002 [ 44.498441][ T7187] Kernel Offset: disabled [ 44.502777][ T7187] Rebooting in 86400 seconds..