[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.448000][ T23] audit: type=1800 audit(1571120737.723:25): pid=7089 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.492160][ T23] audit: type=1800 audit(1571120737.733:26): pid=7089 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.513092][ T23] audit: type=1800 audit(1571120737.733:27): pid=7089 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 '10.128.0.240' (ECDSA) to the list of known hosts. 2019/10/15 06:25:48 fuzzer started 2019/10/15 06:25:50 dialing manager at 10.128.0.105:33683 2019/10/15 06:25:50 syscalls: 2523 2019/10/15 06:25:50 code coverage: enabled 2019/10/15 06:25:50 comparison tracing: enabled 2019/10/15 06:25:50 extra coverage: extra coverage is not supported by the kernel 2019/10/15 06:25:50 setuid sandbox: enabled 2019/10/15 06:25:50 namespace sandbox: enabled 2019/10/15 06:25:50 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/15 06:25:50 fault injection: enabled 2019/10/15 06:25:50 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/15 06:25:50 net packet injection: enabled 2019/10/15 06:25:50 net device setup: enabled 2019/10/15 06:25:50 concurrency sanitizer: enabled syzkaller login: [ 47.374901][ T7240] ================================================================== [ 47.383157][ T7240] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 47.391014][ T7240] [ 47.393325][ T7240] read to 0xffff88812562530c of 4 bytes by interrupt on cpu 0: [ 47.400846][ T7240] tcp_add_backlog+0x43/0xcc0 [ 47.405500][ T7240] tcp_v4_rcv+0x1aba/0x1bf0 [ 47.409982][ T7240] ip_protocol_deliver_rcu+0x51/0x470 [ 47.415341][ T7240] ip_local_deliver_finish+0x110/0x140 [ 47.420818][ T7240] ip_local_deliver+0x133/0x210 [ 47.425649][ T7240] ip_rcv_finish+0x121/0x160 [ 47.430218][ T7240] ip_rcv+0x18f/0x1a0 [ 47.434177][ T7240] __netif_receive_skb_one_core+0xa7/0xe0 [ 47.439873][ T7240] __netif_receive_skb+0x37/0xf0 [ 47.444789][ T7240] netif_receive_skb_internal+0x59/0x190 [ 47.450401][ T7240] napi_gro_receive+0x28f/0x330 [ 47.455226][ T7240] receive_buf+0x284/0x30b0 [ 47.459703][ T7240] virtnet_poll+0x436/0x7d0 [ 47.464179][ T7240] net_rx_action+0x3ae/0xa50 [ 47.468736][ T7240] [ 47.471043][ T7240] write to 0xffff88812562530c of 4 bytes by task 7240 on cpu 1: [ 47.478649][ T7240] tcp_rcv_space_adjust+0x40f/0x4c0 [ 47.483839][ T7240] tcp_recvmsg+0xdaa/0x1a30 [ 47.488337][ T7240] inet_recvmsg+0xbb/0x250 [ 47.492730][ T7240] sock_recvmsg+0x92/0xb0 [ 47.497036][ T7240] sock_read_iter+0x15f/0x1e0 [ 47.501692][ T7240] new_sync_read+0x389/0x4f0 [ 47.506257][ T7240] __vfs_read+0xb1/0xc0 [ 47.510390][ T7240] vfs_read+0x143/0x2c0 [ 47.514519][ T7240] ksys_read+0xd5/0x1b0 [ 47.518663][ T7240] __x64_sys_read+0x4c/0x60 [ 47.523152][ T7240] do_syscall_64+0xcf/0x2f0 [ 47.527633][ T7240] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.533515][ T7240] [ 47.535817][ T7240] Reported by Kernel Concurrency Sanitizer on: [ 47.541955][ T7240] CPU: 1 PID: 7240 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.549032][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.559079][ T7240] ================================================================== [ 47.567119][ T7240] Kernel panic - not syncing: panic_on_warn set ... [ 47.573695][ T7240] CPU: 1 PID: 7240 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.580792][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.590825][ T7240] Call Trace: [ 47.594112][ T7240] dump_stack+0xf5/0x159 [ 47.598334][ T7240] panic+0x209/0x639 [ 47.602212][ T7240] ? ksys_read+0xd5/0x1b0 [ 47.606525][ T7240] ? vprintk_func+0x8d/0x140 [ 47.611110][ T7240] kcsan_report.cold+0xc/0x1b [ 47.615794][ T7240] __kcsan_setup_watchpoint+0x3ee/0x510 [ 47.621590][ T7240] __tsan_write4+0x32/0x40 [ 47.626005][ T7240] tcp_rcv_space_adjust+0x40f/0x4c0 [ 47.631189][ T7240] tcp_recvmsg+0xdaa/0x1a30 [ 47.635726][ T7240] ? __kcsan_setup_watchpoint+0x96/0x510 [ 47.641339][ T7240] inet_recvmsg+0xbb/0x250 [ 47.645732][ T7240] ? __tsan_read8+0x2c/0x30 [ 47.650219][ T7240] ? inet_sendpage+0x100/0x100 [ 47.654966][ T7240] sock_recvmsg+0x92/0xb0 [ 47.659277][ T7240] sock_read_iter+0x15f/0x1e0 [ 47.663937][ T7240] new_sync_read+0x389/0x4f0 [ 47.668512][ T7240] __vfs_read+0xb1/0xc0 [ 47.672666][ T7240] vfs_read+0x143/0x2c0 [ 47.676803][ T7240] ksys_read+0xd5/0x1b0 [ 47.680944][ T7240] __x64_sys_read+0x4c/0x60 [ 47.685448][ T7240] do_syscall_64+0xcf/0x2f0 [ 47.689936][ T7240] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.695826][ T7240] RIP: 0033:0x47c530 [ 47.699723][ T7240] 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 [ 47.719316][ T7240] RSP: 002b:000000c4203bf7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 47.727704][ T7240] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 47.735651][ T7240] RDX: 0000000000001000 RSI: 000000c42006c000 RDI: 0000000000000003 [ 47.743600][ T7240] RBP: 000000c4203bf830 R08: 0000000000000000 R09: 0000000000000000 [ 47.751549][ T7240] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000010 [ 47.759500][ T7240] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 47.768826][ T7240] Kernel Offset: disabled [ 47.773156][ T7240] Rebooting in 86400 seconds..