Fix server reload race: use Shutdown, serialize reloads, eliminate data races#2094
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Fix server reload race: use Shutdown, serialize reloads, eliminate data races#2094
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…ta races When the CertWatcher detects TLS certificate changes, it calls reloadServer which closes the old HTTPS server and starts a new one. The previous implementation used Close() which returns before the listener fully releases the port, causing intermittent 'address already in use' errors on the new ListenAndServeTLS call. Additionally, rapid fsnotify events (e.g. kubelet cert sync triggering remove+create) could invoke reloadServer concurrently, racing on s.httpsServer and the shared tls.Config. Changes: - Replace Close() with Shutdown() to wait for the port to be freed - Add sync.Mutex to serialize concurrent reloadServer calls - Capture server in local variable before goroutine to prevent data race on s.httpsServer field - Clone tls.Config to prevent race between old server shutdown and new server startup - Filter http.ErrServerClosed in both Start and reloadServer since it is expected during reload
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Description of the issue
Follow up to #1957.
When the CertWatcher detects TLS certificate changes, it calls reloadServer which closes the old HTTPS server and starts a new one. The previous implementation used Close() which returns before the listener fully releases the port, causing intermittent 'address already in use' errors on the new ListenAndServeTLS call.
Additionally, rapid fsnotify events (e.g. kubelet cert sync triggering remove+create) could invoke reloadServer concurrently, racing on s.httpsServer and the shared tls.Config.
Description of changes
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Tests
Updated unit tests to simulate race conditions
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