[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.953487][ T25] audit: type=1800 audit(1570634366.592:25): pid=6987 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.998481][ T25] audit: type=1800 audit(1570634366.592:26): pid=6987 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.024755][ T25] audit: type=1800 audit(1570634366.592:27): pid=6987 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. 2019/10/09 15:19:35 fuzzer started 2019/10/09 15:19:36 dialing manager at 10.128.0.105:43333 2019/10/09 15:19:36 syscalls: 2523 2019/10/09 15:19:36 code coverage: enabled 2019/10/09 15:19:36 comparison tracing: enabled 2019/10/09 15:19:36 extra coverage: extra coverage is not supported by the kernel 2019/10/09 15:19:36 setuid sandbox: enabled 2019/10/09 15:19:36 namespace sandbox: enabled 2019/10/09 15:19:36 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/09 15:19:36 fault injection: enabled 2019/10/09 15:19:36 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/09 15:19:36 net packet injection: enabled 2019/10/09 15:19:36 net device setup: enabled 2019/10/09 15:19:36 concurrency sanitizer: enabled syzkaller login: [ 46.187556][ T7143] ================================================================== [ 46.195679][ T7143] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 46.203452][ T7143] [ 46.205758][ T7143] read to 0xffff8881246e930c of 4 bytes by interrupt on cpu 1: [ 46.213276][ T7143] tcp_add_backlog+0x43/0xcc0 [ 46.217928][ T7143] tcp_v4_rcv+0x1aba/0x1bf0 [ 46.222409][ T7143] ip_protocol_deliver_rcu+0x51/0x470 [ 46.227756][ T7143] ip_local_deliver_finish+0x110/0x140 [ 46.233188][ T7143] ip_local_deliver+0x133/0x210 [ 46.238011][ T7143] ip_rcv_finish+0x121/0x160 [ 46.242576][ T7143] ip_rcv+0x18f/0x1a0 [ 46.246533][ T7143] __netif_receive_skb_one_core+0xa7/0xe0 [ 46.252224][ T7143] __netif_receive_skb+0x37/0xf0 [ 46.257173][ T7143] netif_receive_skb_internal+0x59/0x190 [ 46.262781][ T7143] napi_gro_receive+0x28f/0x330 [ 46.267607][ T7143] receive_buf+0x284/0x30b0 [ 46.272085][ T7143] virtnet_poll+0x436/0x7d0 [ 46.276601][ T7143] net_rx_action+0x3ae/0xa50 [ 46.281160][ T7143] [ 46.283465][ T7143] write to 0xffff8881246e930c of 4 bytes by task 7143 on cpu 0: [ 46.291108][ T7143] tcp_rcv_space_adjust+0x40f/0x4c0 [ 46.296280][ T7143] tcp_recvmsg+0xdaa/0x1a30 [ 46.300760][ T7143] inet_recvmsg+0xbb/0x250 [ 46.305148][ T7143] sock_recvmsg+0x92/0xb0 [ 46.309456][ T7143] sock_read_iter+0x15f/0x1e0 [ 46.314124][ T7143] new_sync_read+0x389/0x4f0 [ 46.318689][ T7143] __vfs_read+0xb1/0xc0 [ 46.322820][ T7143] vfs_read+0x143/0x2c0 [ 46.326951][ T7143] ksys_read+0xd5/0x1b0 [ 46.331080][ T7143] __x64_sys_read+0x4c/0x60 [ 46.335562][ T7143] do_syscall_64+0xcf/0x2f0 [ 46.340046][ T7143] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.345904][ T7143] [ 46.348205][ T7143] Reported by Kernel Concurrency Sanitizer on: [ 46.354332][ T7143] CPU: 0 PID: 7143 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.361448][ T7143] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.371478][ T7143] ================================================================== [ 46.379510][ T7143] Kernel panic - not syncing: panic_on_warn set ... [ 46.386073][ T7143] CPU: 0 PID: 7143 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 46.393150][ T7143] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.403176][ T7143] Call Trace: [ 46.406445][ T7143] dump_stack+0xf5/0x159 [ 46.410670][ T7143] panic+0x209/0x639 [ 46.414554][ T7143] ? ksys_read+0xd5/0x1b0 [ 46.418860][ T7143] ? vprintk_func+0x8d/0x140 [ 46.423429][ T7143] kcsan_report.cold+0xc/0x1b [ 46.428083][ T7143] __kcsan_setup_watchpoint+0x3ee/0x510 [ 46.433619][ T7143] __tsan_write4+0x32/0x40 [ 46.438013][ T7143] tcp_rcv_space_adjust+0x40f/0x4c0 [ 46.443193][ T7143] tcp_recvmsg+0xdaa/0x1a30 [ 46.447676][ T7143] ? __kcsan_setup_watchpoint+0x96/0x510 [ 46.453296][ T7143] ? __kcsan_setup_watchpoint+0x96/0x510 [ 46.458907][ T7143] inet_recvmsg+0xbb/0x250 [ 46.463310][ T7143] ? __tsan_read8+0x2c/0x30 [ 46.467793][ T7143] ? inet_sendpage+0x100/0x100 [ 46.472530][ T7143] sock_recvmsg+0x92/0xb0 [ 46.476847][ T7143] sock_read_iter+0x15f/0x1e0 [ 46.481506][ T7143] new_sync_read+0x389/0x4f0 [ 46.486079][ T7143] __vfs_read+0xb1/0xc0 [ 46.490228][ T7143] vfs_read+0x143/0x2c0 [ 46.494362][ T7143] ksys_read+0xd5/0x1b0 [ 46.498495][ T7143] __x64_sys_read+0x4c/0x60 [ 46.502979][ T7143] do_syscall_64+0xcf/0x2f0 [ 46.507488][ T7143] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.513352][ T7143] RIP: 0033:0x47c530 [ 46.517226][ T7143] 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 [ 46.536804][ T7143] RSP: 002b:000000c4203a9810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 46.545189][ T7143] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.553165][ T7143] RDX: 0000000000001000 RSI: 000000c42015c000 RDI: 0000000000000003 [ 46.561120][ T7143] RBP: 000000c4203a9868 R08: 0000000000000000 R09: 0000000000000000 [ 46.569071][ T7143] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 46.577020][ T7143] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 46.586196][ T7143] Kernel Offset: disabled [ 46.590518][ T7143] Rebooting in 86400 seconds..