Wait forever to exit

[ethever]

When you start tun2proxy without a global IP address and then press Ctrl-C to stop it, the process hangs indefinitely.

...
[2025-07-15T01:34:01Z INFO  tun2proxy] Beginning #198 TCP 10.0.0.33:35434 -> 192.168.31.21:10808
[2025-07-15T01:34:01Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:35460 -> 192.168.31.21:10808 Listen: local { seq: 1607316745, ack: 3127895765 } session begins, total TCP sessions: 200
[2025-07-15T01:34:01Z DEBUG ipstack] session created: TCP 10.0.0.33:35460 -> 192.168.31.21:10808
[2025-07-15T01:34:01Z WARN  tun2proxy] Too many sessions that over 200, dropping new session
[2025-07-15T01:34:01Z INFO  tun2proxy] Beginning #199 TCP 10.0.0.33:35450 -> 192.168.31.21:10808
[2025-07-15T01:34:01Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:35460 -> 192.168.31.21:10808 task exited due to exit signal
[2025-07-15T01:34:01Z DEBUG ipstack] session destroyed: TCP 10.0.0.33:35460 -> 192.168.31.21:10808
[2025-07-15T01:34:01Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:35460 -> 192.168.31.21:10808 SynReceived: [drop] session dropped, total TCP sessions: 199


^C[2025-07-15T01:34:25Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
[2025-07-15T01:34:25Z INFO  tun2proxy_bin] Ctrl-C received, exiting...
[2025-07-15T01:34:25Z INFO  tun2proxy] Shutdown received
[2025-07-15T01:34:25Z DEBUG tproxy_config::linux] removing route: RouteMessage { header: RouteHeader { address_family: Inet, destination_prefix_length: 1, source_prefix_length: 0, tos: 0, table: 254, protocol: Static, scope: Universe, kind: Unicast, flags: RouteFlags(0x0) }, attributes: [Destination(Inet(0.0.0.0)), Oif(112)] }
[2025-07-15T01:34:25Z DEBUG tproxy_config::linux] removing route: RouteMessage { header: RouteHeader { address_family: Inet, destination_prefix_length: 1, source_prefix_length: 0, tos: 0, table: 254, protocol: Static, scope: Universe, kind: Unicast, flags: RouteFlags(0x0) }, attributes: [Destination(Inet(128.0.0.0)), Oif(112)] }
[2025-07-15T01:34:25Z DEBUG tproxy_config::linux] deleting link: tun0
[2025-07-15T01:34:25Z DEBUG tproxy_config::linux] unmounting /etc/resolv.conf
[2025-07-15T01:34:25Z DEBUG tproxy_config::common] restoring network settings
[2025-07-15T01:34:25Z INFO  tun2proxy_bin] Ctrl-C fired, waiting the handler to finish...
[2025-07-15T01:34:25Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:34108 -> 192.168.31.21:10808 Established: [drop] session dropped, total TCP sessions: 198
^[[A

^C[2025-07-15T01:34:28Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe

^C[2025-07-15T01:34:30Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:30Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:40Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:40Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:40Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:40Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:40Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:41Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:41Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:41Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:42Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:42Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:42Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-15T01:34:43Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe

[ethever]

here is how i start tun2proxy:

 tun2proxy-bin --setup --proxy "socks5://192.168.31.21:10808" -v trace

[ssrlive]

Is the problem reproducible consistently, or is it encountered sporadically?

[ethever]

Almost every time in my environment. I’ll try to prepare a minimal reproduction when I have some time.

[ssrlive]

try the new version https://github.com/tun2proxy/tun2proxy/releases/tag/v0.7.12 and report the log here.

[blechschmidt]

Could this be the result of a routing loop? Do you see any error message regarding this? Do we run out of file descriptors in this case and does this result in some deadlock? Can you post your routing table before and after starting tun2proxy?

[ssrlive]

I think this was a logic flaw in the ctrlc2 crate, which has probably been fixed by now.

[ssrlive]

Hi @ethever please post your test log info here with latest release binary.

[ethever]

[2025-07-18T05:30:05Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:59744 -> 192.168.68.126:10808 Listen: local { seq: 4178058912, ack: 2282069556 } session begins, total TCP sessions: 1010
[2025-07-18T05:30:05Z DEBUG ipstack] session created: TCP 10.0.0.33:59744 -> 192.168.68.126:10808
[2025-07-18T05:30:05Z INFO  tun2proxy] Beginning #1009 TCP 10.0.0.33:59740 -> 192.168.68.126:10808
[2025-07-18T05:30:05Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:59746 -> 192.168.68.126:10808 Listen: local { seq: 3477513249, ack: 4057253018 } session begins, total TCP sessions: 1011
[2025-07-18T05:30:05Z DEBUG ipstack] session created: TCP 10.0.0.33:59746 -> 192.168.68.126:10808
[2025-07-18T05:30:05Z INFO  tun2proxy] Beginning #1010 TCP 10.0.0.33:59744 -> 192.168.68.126:10808
[2025-07-18T05:30:05Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:59746 -> 192.168.68.126:10808 task exited due to exit signal
[2025-07-18T05:30:05Z DEBUG ipstack] session destroyed: TCP 10.0.0.33:59746 -> 192.168.68.126:10808
[2025-07-18T05:30:05Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:59746 -> 192.168.68.126:10808 Established: [drop] session dropped, total TCP sessions: 1010
[2025-07-18T05:30:05Z ERROR tun2proxy] #1011 TCP 10.0.0.33:59746 -> 192.168.68.126:10808 error "Too many open files (os error 24)"
[2025-07-18T05:30:06Z INFO  tun2proxy] #0 unhandled transport - Ip Protocol 58 (IPv6-ICMP - ICMP for IPv6), length 8
[2025-07-18T05:30:13Z INFO  tun2proxy] #0 unhandled transport - Ip Protocol 58 (IPv6-ICMP - ICMP for IPv6), length 8
[2025-07-18T05:30:27Z INFO  tun2proxy] #0 unhandled transport - Ip Protocol 58 (IPv6-ICMP - ICMP for IPv6), length 8
^C[2025-07-18T05:30:44Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
[2025-07-18T05:30:44Z INFO  tun2proxy_bin] Ctrl-C received, exiting...
[2025-07-18T05:30:44Z DEBUG ctrlc2::r#async] AsyncCtrlC: waker was not set, cannot wake up
[2025-07-18T05:30:44Z INFO  tun2proxy] Shutdown received
[2025-07-18T05:30:44Z DEBUG tproxy_config::linux] removing route: RouteMessage { header: RouteHeader { address_family: Inet, destination_prefix_length: 1, source_prefix_length: 0, tos: 0, table: 254, protocol: Static, scope: Universe, kind: Unicast, flags: RouteFlags(0x0) }, attributes: [Destination(Inet(0.0.0.0)), Oif(51)] }

thread 'tokio-runtime-worker' panicked at /root/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tproxy-config-7.0.0/src/linux.rs:48:56:
called `Result::unwrap()` on an `Err` value: Os { code: 24, kind: Uncategorized, message: "Too many open files" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[2025-07-18T05:30:44Z DEBUG tproxy_config::common] restoring network settings
[2025-07-18T05:30:44Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:50622 -> 192.168.68.126:10808 Established: [drop] session dropped, total TCP sessions: 1009
[2025-07-18T05:30:44Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:50960 -> 192.168.68.126:10808 Established: [drop] session dropped, total TCP sessions: 1008
[2025-07-18T05:30:44Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:50816 -> 192.168.68.126:10808 Established: [drop] session dropped, total TCP sessions: 1007
[2025-07-18T05:30:44Z DEBUG ipstack::stream::tcp] TCP 10.0.0.33:51564 -> 192.168.68.126:10808 Established: [drop] session dropped, total TCP sessions: 1006
^C[2025-07-18T05:30:44Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:44Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:47Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:47Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:47Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:47Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:48Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:48Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe
^C[2025-07-18T05:30:49Z DEBUG ctrlc2::platform::unix] Ctrl-C event received, writing to pipe

[ethever]

root@ser7:~# tun2proxy-bin --version
tun2proxy 0.7.12 ( 2025-07-18 05:27:38)

[ssrlive]

Damn! The error location this time is different from last time.

[ssrlive]

your machine? uname -a @ethever

[ethever]

root@ser7:~# uname -a
Linux ser7 6.6.36.3-microsoft-standard-WSL2+ #1 SMP PREEMPT_DYNAMIC Wed Jul 31 02:09:31 CST 2024 x86_64 GNU/Linux