fix(protocol): don't panic on startup when initial peer set exceeds channel capacity#5104
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damip wants to merge 1 commit into
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fix(protocol): don't panic on startup when initial peer set exceeds channel capacity#5104damip wants to merge 1 commit into
damip wants to merge 1 commit into
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…hannel capacity PeerManagementHandler::new pushed each merged initial/bootstrap peer into a bounded channel with try_send(...).unwrap(). An over-capacity peer list made unwrap() panic on the startup path, potentially preventing the node from joining the network. Log and skip on send error instead. Finding F139. Co-authored-by: Cursor <cursoragent@cursor.com>
modship
approved these changes
Jul 22, 2026
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Summary
In
PeerManagementHandler::new, the initial peer set — the union of locallyconfigured
initial_peersand network-providedbootstrap_peers— is pushed into abounded channel with
sender_msg.try_send(...).unwrap(), one message per peer.There is no check that the merged peer count fits
max_size_channel_network_to_peer_handler. If the combined list exceeds the channelcapacity,
try_sendreturnsFull, theunwrap()panics, and because this runs onthe node's startup path the node can fail to join the network.
Change
Replace the
unwrap()with graceful handling: on atry_senderror, log a warningand skip that peer. Dropping an excess peer at startup is safe — peers are
(re)discovered through normal peer exchange — and it must not abort node startup.
Testing
cargo build/cargo clippyclean formassa_protocol_worker.unwrap()→ error-logging conversion inside a constructorthat spawns the peer-management thread; reproducing channel saturation deterministically
would require a full handler harness, so no dedicated unit test is added.
Risk
Low — the only behavioural change is that an over-capacity initial peer list now logs
and continues instead of panicking. Under normal configuration the channel is not
saturated and behaviour is unchanged.
Tracking: finding F139.