[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.499873][ T25] audit: type=1800 audit(1571757480.290:25): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.536232][ T25] audit: type=1800 audit(1571757480.290:26): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.557228][ T25] audit: type=1800 audit(1571757480.290:27): pid=7026 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 '10.128.10.44' (ECDSA) to the list of known hosts. 2019/10/22 15:18:12 fuzzer started 2019/10/22 15:18:13 dialing manager at 10.128.0.105:33369 2019/10/22 15:18:13 syscalls: 2524 2019/10/22 15:18:13 code coverage: enabled 2019/10/22 15:18:13 comparison tracing: enabled 2019/10/22 15:18:13 extra coverage: extra coverage is not supported by the kernel 2019/10/22 15:18:13 setuid sandbox: enabled 2019/10/22 15:18:13 namespace sandbox: enabled 2019/10/22 15:18:13 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 15:18:13 fault injection: enabled 2019/10/22 15:18:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 15:18:13 net packet injection: enabled 2019/10/22 15:18:13 net device setup: enabled 2019/10/22 15:18:13 concurrency sanitizer: enabled syzkaller login: [ 49.685925][ T7192] ================================================================== [ 49.694072][ T7192] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 49.701089][ T7192] [ 49.703526][ T7192] write to 0xffff888126af8138 of 8 bytes by interrupt on cpu 0: [ 49.711291][ T7192] tcp_add_backlog+0x45a/0xcc0 [ 49.716036][ T7192] tcp_v4_rcv+0x1a60/0x1bb0 [ 49.720520][ T7192] ip_protocol_deliver_rcu+0x4d/0x420 [ 49.725888][ T7192] ip_local_deliver_finish+0x110/0x140 [ 49.731326][ T7192] ip_local_deliver+0x133/0x210 [ 49.736246][ T7192] ip_rcv_finish+0x121/0x160 [ 49.740811][ T7192] ip_rcv+0x18f/0x1a0 [ 49.744778][ T7192] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.750476][ T7192] __netif_receive_skb+0x37/0xf0 [ 49.755399][ T7192] netif_receive_skb_internal+0x59/0x190 [ 49.761016][ T7192] napi_gro_receive+0x28f/0x330 [ 49.765853][ T7192] receive_buf+0x284/0x30b0 [ 49.770332][ T7192] virtnet_poll+0x436/0x7d0 [ 49.774823][ T7192] net_rx_action+0x3ae/0xa90 [ 49.779394][ T7192] [ 49.781703][ T7192] read to 0xffff888126af8138 of 8 bytes by task 7192 on cpu 1: [ 49.789222][ T7192] tcp_recvmsg+0x470/0x1a30 [ 49.793699][ T7192] inet_recvmsg+0xbb/0x250 [ 49.798091][ T7192] sock_recvmsg+0x92/0xb0 [ 49.802397][ T7192] sock_read_iter+0x15f/0x1e0 [ 49.807050][ T7192] new_sync_read+0x389/0x4f0 [ 49.811627][ T7192] __vfs_read+0xb1/0xc0 [ 49.815759][ T7192] vfs_read+0x143/0x2c0 [ 49.819901][ T7192] ksys_read+0xd5/0x1b0 [ 49.824032][ T7192] __x64_sys_read+0x4c/0x60 [ 49.828518][ T7192] do_syscall_64+0xcc/0x370 [ 49.832997][ T7192] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.839055][ T7192] [ 49.841450][ T7192] Reported by Kernel Concurrency Sanitizer on: [ 49.847584][ T7192] CPU: 1 PID: 7192 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.855020][ T7192] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.865061][ T7192] ================================================================== [ 49.873097][ T7192] Kernel panic - not syncing: panic_on_warn set ... [ 49.879682][ T7192] CPU: 1 PID: 7192 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 49.887128][ T7192] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.897170][ T7192] Call Trace: [ 49.900443][ T7192] dump_stack+0xf5/0x159 [ 49.904673][ T7192] panic+0x210/0x640 [ 49.908547][ T7192] ? __x64_sys_read+0x4c/0x60 [ 49.913207][ T7192] ? vprintk_func+0x8d/0x140 [ 49.917785][ T7192] kcsan_report.cold+0xc/0x10 [ 49.922449][ T7192] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 49.927994][ T7192] __tsan_read8+0x2c/0x30 [ 49.932305][ T7192] tcp_recvmsg+0x470/0x1a30 [ 49.936804][ T7192] inet_recvmsg+0xbb/0x250 [ 49.941348][ T7192] ? __tsan_read8+0x2c/0x30 [ 49.945855][ T7192] ? inet_sendpage+0x100/0x100 [ 49.950668][ T7192] sock_recvmsg+0x92/0xb0 [ 49.954980][ T7192] sock_read_iter+0x15f/0x1e0 [ 49.959677][ T7192] new_sync_read+0x389/0x4f0 [ 49.964298][ T7192] __vfs_read+0xb1/0xc0 [ 49.968433][ T7192] vfs_read+0x143/0x2c0 [ 49.972577][ T7192] ksys_read+0xd5/0x1b0 [ 49.976710][ T7192] __x64_sys_read+0x4c/0x60 [ 49.981201][ T7192] do_syscall_64+0xcc/0x370 [ 49.985683][ T7192] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.991548][ T7192] RIP: 0033:0x47c530 [ 49.995429][ T7192] 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 [ 50.015025][ T7192] RSP: 002b:000000c4203197d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 50.023421][ T7192] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.031378][ T7192] RDX: 0000000000001000 RSI: 000000c4200a2000 RDI: 0000000000000003 [ 50.039337][ T7192] RBP: 000000c420319830 R08: 0000000000000000 R09: 0000000000000000 [ 50.047301][ T7192] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 50.055249][ T7192] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 50.064352][ T7192] Kernel Offset: disabled [ 50.068673][ T7192] Rebooting in 86400 seconds..