[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.677275][ T23] audit: type=1800 audit(1570192855.339:25): pid=7128 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.697099][ T23] audit: type=1800 audit(1570192855.339:26): pid=7128 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.717146][ T23] audit: type=1800 audit(1570192855.339:27): pid=7128 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 '10.128.0.34' (ECDSA) to the list of known hosts. 2019/10/04 12:41:05 fuzzer started 2019/10/04 12:41:06 dialing manager at 10.128.0.105:38119 2019/10/04 12:41:06 syscalls: 2523 2019/10/04 12:41:06 code coverage: enabled 2019/10/04 12:41:06 comparison tracing: enabled 2019/10/04 12:41:06 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:41:06 setuid sandbox: enabled 2019/10/04 12:41:06 namespace sandbox: enabled 2019/10/04 12:41:06 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:41:06 fault injection: enabled 2019/10/04 12:41:06 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:41:06 net packet injection: enabled 2019/10/04 12:41:06 net device setup: enabled 2019/10/04 12:41:06 concurrency sanitizer: enabled syzkaller login: [ 49.584588][ T7285] ================================================================== [ 49.592828][ T7285] BUG: KCSAN: data-race in tcp_add_backlog+0x45a/0xcc0 and tcp_recvmsg+0x470/0x1a30 [ 49.602587][ T7285] [ 49.604905][ T7285] write to 0xffff8881230592f8 of 8 bytes by interrupt on cpu 1: [ 49.612631][ T7285] tcp_add_backlog+0x45a/0xcc0 [ 49.617375][ T7285] tcp_v4_rcv+0x1aba/0x1bf0 [ 49.621865][ T7285] ip_protocol_deliver_rcu+0x51/0x470 [ 49.627227][ T7285] ip_local_deliver_finish+0x110/0x140 [ 49.632668][ T7285] ip_local_deliver+0x133/0x210 [ 49.637499][ T7285] ip_rcv_finish+0x121/0x160 [ 49.642063][ T7285] ip_rcv+0x18f/0x1a0 [ 49.646041][ T7285] __netif_receive_skb_one_core+0xa7/0xe0 [ 49.651743][ T7285] __netif_receive_skb+0x37/0xf0 [ 49.656657][ T7285] netif_receive_skb_internal+0x59/0x190 [ 49.663044][ T7285] napi_gro_receive+0x28f/0x330 [ 49.667871][ T7285] receive_buf+0x284/0x30b0 [ 49.672348][ T7285] virtnet_poll+0x436/0x7d0 [ 49.676827][ T7285] net_rx_action+0x3ae/0xa50 [ 49.681392][ T7285] [ 49.683704][ T7285] read to 0xffff8881230592f8 of 8 bytes by task 7285 on cpu 0: [ 49.691249][ T7285] tcp_recvmsg+0x470/0x1a30 [ 49.695766][ T7285] inet_recvmsg+0xbb/0x250 [ 49.700159][ T7285] sock_recvmsg+0x92/0xb0 [ 49.704484][ T7285] sock_read_iter+0x15f/0x1e0 [ 49.709144][ T7285] new_sync_read+0x389/0x4f0 [ 49.713732][ T7285] __vfs_read+0xb1/0xc0 [ 49.717980][ T7285] vfs_read+0x143/0x2c0 [ 49.722153][ T7285] ksys_read+0xd5/0x1b0 [ 49.726291][ T7285] __x64_sys_read+0x4c/0x60 [ 49.730789][ T7285] do_syscall_64+0xcf/0x2f0 [ 49.735287][ T7285] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.741151][ T7285] [ 49.746460][ T7285] Reported by Kernel Concurrency Sanitizer on: [ 49.752593][ T7285] CPU: 0 PID: 7285 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.759854][ T7285] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.769898][ T7285] ================================================================== [ 49.777944][ T7285] Kernel panic - not syncing: panic_on_warn set ... [ 49.784509][ T7285] CPU: 0 PID: 7285 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.791605][ T7285] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.801643][ T7285] Call Trace: [ 49.804917][ T7285] dump_stack+0xf5/0x159 [ 49.809769][ T7285] panic+0x209/0x639 [ 49.813670][ T7285] ? vprintk_func+0x8d/0x140 [ 49.818483][ T7285] kcsan_report.cold+0x57/0xeb [ 49.823364][ T7285] __kcsan_setup_watchpoint+0x342/0x500 [ 49.828898][ T7285] __tsan_read8+0x2c/0x30 [ 49.833250][ T7285] tcp_recvmsg+0x470/0x1a30 [ 49.837741][ T7285] ? __const_udelay+0x36/0x40 [ 49.842399][ T7285] inet_recvmsg+0xbb/0x250 [ 49.846808][ T7285] ? __tsan_read8+0x2c/0x30 [ 49.851300][ T7285] ? inet_sendpage+0x100/0x100 [ 49.856041][ T7285] sock_recvmsg+0x92/0xb0 [ 49.860348][ T7285] sock_read_iter+0x15f/0x1e0 [ 49.865008][ T7285] new_sync_read+0x389/0x4f0 [ 49.869595][ T7285] __vfs_read+0xb1/0xc0 [ 49.873735][ T7285] vfs_read+0x143/0x2c0 [ 49.877895][ T7285] ksys_read+0xd5/0x1b0 [ 49.882038][ T7285] __x64_sys_read+0x4c/0x60 [ 49.886525][ T7285] do_syscall_64+0xcf/0x2f0 [ 49.891021][ T7285] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.896889][ T7285] RIP: 0033:0x47c530 [ 49.900764][ T7285] 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 [ 49.920356][ T7285] RSP: 002b:000000c4204dd810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 49.928751][ T7285] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 49.936702][ T7285] RDX: 0000000000001000 RSI: 000000c420194000 RDI: 0000000000000003 [ 49.944651][ T7285] RBP: 000000c4204dd868 R08: 0000000000000000 R09: 0000000000000000 [ 49.952602][ T7285] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 [ 49.960552][ T7285] R13: 000000c420083e50 R14: 0000000000000002 R15: ffffffffffffffff [ 49.969920][ T7285] Kernel Offset: disabled [ 49.974244][ T7285] Rebooting in 86400 seconds..