[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.726312][ T26] audit: type=1800 audit(1571754270.747:25): pid=6993 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.753380][ T26] audit: type=1800 audit(1571754270.757:26): pid=6993 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.792539][ T26] audit: type=1800 audit(1571754270.757:27): pid=6993 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 '10.128.0.138' (ECDSA) to the list of known hosts. 2019/10/22 14:24:38 fuzzer started 2019/10/22 14:24:40 dialing manager at 10.128.0.105:33369 2019/10/22 14:24:40 syscalls: 2524 2019/10/22 14:24:40 code coverage: enabled 2019/10/22 14:24:40 comparison tracing: enabled 2019/10/22 14:24:40 extra coverage: extra coverage is not supported by the kernel 2019/10/22 14:24:40 setuid sandbox: enabled 2019/10/22 14:24:40 namespace sandbox: enabled 2019/10/22 14:24:40 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 14:24:40 fault injection: enabled 2019/10/22 14:24:40 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 14:24:40 net packet injection: enabled 2019/10/22 14:24:40 net device setup: enabled 2019/10/22 14:24:40 concurrency sanitizer: enabled syzkaller login: [ 45.633134][ T7148] ================================================================== [ 45.641273][ T7148] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 45.648277][ T7148] [ 45.650673][ T7148] write to 0xffff888125511338 of 8 bytes by interrupt on cpu 1: [ 45.658280][ T7148] tcp_add_backlog+0x45a/0xcc0 [ 45.663144][ T7148] tcp_v4_rcv+0x1a60/0x1bb0 [ 45.667650][ T7148] ip_protocol_deliver_rcu+0x4d/0x420 [ 45.672999][ T7148] ip_local_deliver_finish+0x110/0x140 [ 45.678432][ T7148] ip_local_deliver+0x133/0x210 [ 45.683257][ T7148] ip_rcv_finish+0x121/0x160 [ 45.687838][ T7148] ip_rcv+0x18f/0x1a0 [ 45.691802][ T7148] __netif_receive_skb_one_core+0xa7/0xe0 [ 45.697498][ T7148] __netif_receive_skb+0x37/0xf0 [ 45.702411][ T7148] netif_receive_skb_internal+0x59/0x190 [ 45.708209][ T7148] napi_gro_receive+0x28f/0x330 [ 45.713034][ T7148] receive_buf+0x284/0x30b0 [ 45.717513][ T7148] virtnet_poll+0x436/0x7d0 [ 45.721991][ T7148] net_rx_action+0x3ae/0xa90 [ 45.726575][ T7148] [ 45.728883][ T7148] read to 0xffff888125511338 of 8 bytes by task 7148 on cpu 0: [ 45.736414][ T7148] tcp_recvmsg+0x470/0x1a30 [ 45.740907][ T7148] inet_recvmsg+0xbb/0x250 [ 45.745303][ T7148] sock_recvmsg+0x92/0xb0 [ 45.749610][ T7148] sock_read_iter+0x15f/0x1e0 [ 45.754264][ T7148] new_sync_read+0x389/0x4f0 [ 45.758843][ T7148] __vfs_read+0xb1/0xc0 [ 45.762982][ T7148] vfs_read+0x143/0x2c0 [ 45.767127][ T7148] ksys_read+0xd5/0x1b0 [ 45.771258][ T7148] __x64_sys_read+0x4c/0x60 [ 45.775760][ T7148] do_syscall_64+0xcc/0x370 [ 45.780256][ T7148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.786130][ T7148] [ 45.788445][ T7148] Reported by Kernel Concurrency Sanitizer on: [ 45.794577][ T7148] CPU: 0 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.802001][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.812046][ T7148] ================================================================== [ 45.820091][ T7148] Kernel panic - not syncing: panic_on_warn set ... [ 45.826669][ T7148] CPU: 0 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.834108][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.844148][ T7148] Call Trace: [ 45.847434][ T7148] dump_stack+0xf5/0x159 [ 45.851654][ T7148] panic+0x210/0x640 [ 45.855532][ T7148] ? __x64_sys_read+0x4c/0x60 [ 45.860188][ T7148] ? vprintk_func+0x8d/0x140 [ 45.864759][ T7148] kcsan_report.cold+0xc/0x10 [ 45.869513][ T7148] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 45.875036][ T7148] __tsan_read8+0x2c/0x30 [ 45.879345][ T7148] tcp_recvmsg+0x470/0x1a30 [ 45.883835][ T7148] inet_recvmsg+0xbb/0x250 [ 45.888228][ T7148] ? __tsan_read8+0x2c/0x30 [ 45.892722][ T7148] ? inet_sendpage+0x100/0x100 [ 45.897477][ T7148] sock_recvmsg+0x92/0xb0 [ 45.901798][ T7148] sock_read_iter+0x15f/0x1e0 [ 45.906479][ T7148] new_sync_read+0x389/0x4f0 [ 45.911051][ T7148] __vfs_read+0xb1/0xc0 [ 45.915184][ T7148] vfs_read+0x143/0x2c0 [ 45.919318][ T7148] ksys_read+0xd5/0x1b0 [ 45.923467][ T7148] __x64_sys_read+0x4c/0x60 [ 45.927953][ T7148] do_syscall_64+0xcc/0x370 [ 45.932434][ T7148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.938316][ T7148] RIP: 0033:0x47c530 [ 45.942214][ T7148] 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 [ 45.961792][ T7148] RSP: 002b:000000c4204e97d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 45.970189][ T7148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 45.978148][ T7148] RDX: 0000000000001000 RSI: 000000c42031e000 RDI: 0000000000000003 [ 45.986208][ T7148] RBP: 000000c4204e9830 R08: 0000000000000000 R09: 0000000000000000 [ 45.994245][ T7148] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 46.002210][ T7148] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 46.011695][ T7148] Kernel Offset: disabled [ 46.016029][ T7148] Rebooting in 86400 seconds..