Fix sockets not getting an ephemeral port between bind() and listen()

[Arshia001]

No description provided.

[Copilot]

Pull request overview

This PR addresses wasix TCP semantics so bind(..., port=0) allocates an ephemeral port immediately (before listen()/connect()), matching POSIX behavior and fixing #6403. It does so by introducing an explicit “bound TCP” state in virtual-net and plumbing it through wasix, journaling, and tests.

Changes:

• Add WASIX wasm regression tests for bind(port=0) behavior (port becomes nonzero after bind(); remains stable after listen()/connect()).
• Extend virtual-net with bind_tcp + VirtualTcpBoundSocket, implement it for host/loopback/remote backends, and add unit tests.
• Update wasix socket state machine + journaling to capture the effective bound address (including ephemeral port).

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
lib/wasix/tests/wasm_tests/socket_tests/bind-port-zero/main.c	New wasm test asserting ephemeral port allocation happens at bind() and is stable across listen().
lib/wasix/tests/wasm_tests/socket_tests/bind-port-zero/build.sh	Build script for the new wasm test.
lib/wasix/tests/wasm_tests/socket_tests/bind-port-zero-connect/main.c	New wasm test asserting bind-assigned ephemeral port stays stable across connect().
lib/wasix/tests/wasm_tests/socket_tests/bind-port-zero-connect/build.sh	Build script for the new wasm test.
lib/wasix/tests/wasm_tests/socket_tests.rs	Registers the two new wasm socket tests in the Rust harness.
lib/wasix/src/syscalls/wasix/sock_bind.rs	Journals the effective local address after bind (important for port=0 correctness in replay).
lib/wasix/src/net/socket.rs	Introduces BoundTcp inode socket state; updates bind/listen/connect/addr_local/status paths accordingly.
lib/virtual-net/src/lib.rs	Adds VirtualNetworking::bind_tcp and the VirtualTcpBoundSocket trait.
lib/virtual-net/src/host.rs	Implements bind_tcp using socket2 and adds LocalTcpBoundSocket.
lib/virtual-net/src/loopback.rs	Implements bind_tcp for loopback and allocates ephemeral ports at bind time.
lib/virtual-net/src/meta.rs	Extends remote protocol with BindTcp, ListenBound, and ConnectBound.
lib/virtual-net/src/client.rs	Implements remote bind_tcp and bound-socket transitions; adds binding-ownership tracking.
lib/virtual-net/src/server.rs	Implements server-side handling for BindTcp and bound-socket transitions.
lib/virtual-net/src/tests.rs	Adds tests covering ephemeral port allocation at bind and stability across listen/connect.
docs/dev/issue-6403-tcp-bind-plan.md	Adds an implementation plan / rationale document for #6403.

Comments suppressed due to low confidence (1)

lib/virtual-net/src/client.rs:930

• RemoteNetworkingClient::new_socket() inserts per-socket entries into accept_tx and sent_tx, but Drop for RemoteSocket only removes recv_tx and recv_with_addr_tx. This will grow the maps over time (socket IDs are monotonically increasing) and can leak memory/resources. Remove the corresponding accept_tx and sent_tx entries on drop as well (guarded by owns_socket_bindings, like the others).

        self.common.recv_tx.lock().unwrap().remove(&self.socket_id);
        self.common
            .recv_with_addr_tx
            .lock()
            .unwrap()
            .remove(&self.socket_id);

[artemyarulin]

/patchsmith test

[Arshia001]

too early @artem, let's wait for CI to turn green first

[artemyarulin]

Cool, but can you resubmit it as PR on branch in this repo? patchsmith unfortunately doesn't run on the forks yet

[Arshia001]

will do once all patches are in @artemyarulin

[Arshia001]

Superseded by #6478