[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.589144][ T25] audit: type=1800 audit(1571743437.879:25): pid=6953 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.616091][ T25] audit: type=1800 audit(1571743437.879:26): pid=6953 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.655474][ T25] audit: type=1800 audit(1571743437.879:27): pid=6953 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 '10.128.0.124' (ECDSA) to the list of known hosts. 2019/10/22 11:24:08 fuzzer started 2019/10/22 11:24:10 dialing manager at 10.128.0.105:37053 2019/10/22 11:24:10 syscalls: 2524 2019/10/22 11:24:10 code coverage: enabled 2019/10/22 11:24:10 comparison tracing: enabled 2019/10/22 11:24:10 extra coverage: extra coverage is not supported by the kernel 2019/10/22 11:24:10 setuid sandbox: enabled 2019/10/22 11:24:10 namespace sandbox: enabled 2019/10/22 11:24:10 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 11:24:10 fault injection: enabled 2019/10/22 11:24:10 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 11:24:10 net packet injection: enabled 2019/10/22 11:24:10 net device setup: enabled 2019/10/22 11:24:10 concurrency sanitizer: enabled syzkaller login: [ 50.595317][ T7124] ================================================================== [ 50.603458][ T7124] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 50.610464][ T7124] [ 50.612788][ T7124] write to 0xffff88812305c138 of 8 bytes by interrupt on cpu 1: [ 50.620410][ T7124] tcp_add_backlog+0x45a/0xcc0 [ 50.625169][ T7124] tcp_v4_rcv+0x1a60/0x1bb0 [ 50.629664][ T7124] ip_protocol_deliver_rcu+0x4d/0x420 [ 50.635029][ T7124] ip_local_deliver_finish+0x110/0x140 [ 50.640537][ T7124] ip_local_deliver+0x133/0x210 [ 50.645473][ T7124] ip_rcv_finish+0x121/0x160 [ 50.650036][ T7124] ip_rcv+0x18f/0x1a0 [ 50.653995][ T7124] __netif_receive_skb_one_core+0xa7/0xe0 [ 50.659692][ T7124] __netif_receive_skb+0x37/0xf0 [ 50.664607][ T7124] netif_receive_skb_internal+0x59/0x190 [ 50.670214][ T7124] napi_gro_receive+0x28f/0x330 [ 50.675039][ T7124] receive_buf+0x284/0x30b0 [ 50.679517][ T7124] virtnet_poll+0x436/0x7d0 [ 50.683994][ T7124] net_rx_action+0x3ae/0xa90 [ 50.688554][ T7124] [ 50.690861][ T7124] read to 0xffff88812305c138 of 8 bytes by task 7124 on cpu 0: [ 50.698379][ T7124] tcp_recvmsg+0x470/0x1a30 [ 50.702855][ T7124] inet_recvmsg+0xbb/0x250 [ 50.707249][ T7124] sock_recvmsg+0x92/0xb0 [ 50.711554][ T7124] sock_read_iter+0x15f/0x1e0 [ 50.716207][ T7124] new_sync_read+0x389/0x4f0 [ 50.720781][ T7124] __vfs_read+0xb1/0xc0 [ 50.724909][ T7124] vfs_read+0x143/0x2c0 [ 50.729055][ T7124] ksys_read+0xd5/0x1b0 [ 50.733186][ T7124] __x64_sys_read+0x4c/0x60 [ 50.737665][ T7124] do_syscall_64+0xcc/0x370 [ 50.742150][ T7124] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.748009][ T7124] [ 50.750314][ T7124] Reported by Kernel Concurrency Sanitizer on: [ 50.756455][ T7124] CPU: 0 PID: 7124 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.763899][ T7124] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.773947][ T7124] ================================================================== [ 50.781979][ T7124] Kernel panic - not syncing: panic_on_warn set ... [ 50.788541][ T7124] CPU: 0 PID: 7124 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.796572][ T7124] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.806602][ T7124] Call Trace: [ 50.809869][ T7124] dump_stack+0xf5/0x159 [ 50.814088][ T7124] panic+0x210/0x640 [ 50.817959][ T7124] ? __x64_sys_read+0x4c/0x60 [ 50.822612][ T7124] ? vprintk_func+0x8d/0x140 [ 50.827180][ T7124] kcsan_report.cold+0xc/0x10 [ 50.831834][ T7124] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 50.837355][ T7124] __tsan_read8+0x2c/0x30 [ 50.841662][ T7124] tcp_recvmsg+0x470/0x1a30 [ 50.846161][ T7124] inet_recvmsg+0xbb/0x250 [ 50.850549][ T7124] ? __tsan_read8+0x2c/0x30 [ 50.855040][ T7124] ? inet_sendpage+0x100/0x100 [ 50.859782][ T7124] sock_recvmsg+0x92/0xb0 [ 50.864093][ T7124] sock_read_iter+0x15f/0x1e0 [ 50.868748][ T7124] new_sync_read+0x389/0x4f0 [ 50.873317][ T7124] __vfs_read+0xb1/0xc0 [ 50.877448][ T7124] vfs_read+0x143/0x2c0 [ 50.881599][ T7124] ksys_read+0xd5/0x1b0 [ 50.885739][ T7124] __x64_sys_read+0x4c/0x60 [ 50.890235][ T7124] do_syscall_64+0xcc/0x370 [ 50.894724][ T7124] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.900595][ T7124] RIP: 0033:0x47c530 [ 50.904477][ T7124] 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 [ 50.924057][ T7124] RSP: 002b:000000c4204e17d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 50.932440][ T7124] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.940391][ T7124] RDX: 0000000000001000 RSI: 000000c420150000 RDI: 0000000000000003 [ 50.948337][ T7124] RBP: 000000c4204e1830 R08: 0000000000000000 R09: 0000000000000000 [ 50.956286][ T7124] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000004 [ 50.964233][ T7124] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 50.973466][ T7124] Kernel Offset: disabled [ 50.977789][ T7124] Rebooting in 86400 seconds..