p2p: read dial scheduler bookkeeping under the lock - #1026
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getCandidates releases ds.mu after copying the static nodes, then keeps reading connectedAll, static, connectedOutbound and dialing. Those sets have no internal synchronisation and are written from the handshake, peer and dial goroutines, so the reads race with ordinary peer churn. The logging reads happen at any log level, because the arguments are evaluated before the call. Take the four counts while the lock is still held and use the local values afterwards. The lock cannot simply be extended over the rest of the function: the dynamic candidate path acquires it again, and sync.RWMutex is not reentrant. Constraint: the lock must be released before the dynamic candidate lookup Rejected: hold ds.mu for the whole function | dynamicCandidateAllowed re-acquires it, which deadlocks once a writer is queued Rejected: give typedNodeSet its own mutex | doubles the locking and breaks reading several sets as one consistent snapshot Confidence: high Scope-risk: narrow Not-tested: no dedicated regression test; TestServerDial catches a reintroduction under -race in roughly half of its runs Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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Problem
getCandidatesreleasesds.muafter copying the static nodes, then keeps readingconnectedAll,static,connectedOutboundanddialing, which are written from the handshake, peer and dial goroutines.Fix
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I have read the CLA Document and I hereby sign the CLAin first time contribute after having read CLA$ make test)Related issues
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