fix(introspector): bound discover_server awaits with timeouts, fix mcp-server lock DoS#127
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…p-server lock DoS Introspector::discover_server connected to downstream MCP servers and awaited list_all_tools with no timeout, so a hung or malicious server blocked the call forever. In mcp-execution-server this was serialized behind a single global Arc<Mutex<Introspector>>, letting one bad server block introspect_server for every session indefinitely. Add connect_timeout/discover_timeout to ServerConfig (30s defaults) and wrap both awaits in tokio::time::timeout, mapping expiry to the existing Error::Timeout variant. Replace the global mutex in GeneratorService with a per-server-id keyed lock, evicting each entry once discover_server completes so unrelated server ids never contend and the map stays bounded. Closes #120
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Summary
Introspector::discover_serverconnected to downstream MCP servers and awaitedlist_all_toolswith no timeout, so a hung or malicious server blocked the call forever.mcp-execution-server, this was made worse by a single globalArc<Mutex<Introspector>>: one hung server blockedintrospect_serverfor every session, not just the caller who triggered it.connect_timeout/discover_timeoutfields toServerConfig(30s defaults) and wraps both awaits intokio::time::timeout, mapping expiry to the existingError::Timeoutvariant.GeneratorServicewith a per-server-id keyed lock (introspector_for), evicting each entry oncediscover_servercompletes (success or error) so unrelated server ids never contend and the map stays bounded against caller-supplied ids.Test plan
cargo +nightly fmt --checkcargo +stable clippy --all-targets --all-features --workspace -- -D warningscargo nextest run --all-features --workspace --no-fail-fastcargo test --doc --all-features --workspaceRUSTDOCFLAGS="--deny rustdoc::broken_intra_doc_links" cargo doc --no-deps --workspaceCloses #120