fix(consensus): apply finalized peer block from local stash#793
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github-actions[bot] merged 1 commit intoJun 5, 2026
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On FinalizeBlock for a peer-proposed block the node already held the block (it had voted for it; hash matches the action's block_hash, justification carries the 2/3 precommit certificate) but refused to apply it unless it was the local proposer — instead triggering libp2p sync and breaking. When NewBlock gossip missed, the node sat in Finalize re-requesting a block it already had, stalling/crawling the chain. Apply it locally like the self-propose arm; validate_block still re-checks structure + justification supermajority before the write. No state_root/format change.
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Problem
After the Pass-2 rollback fix (#792) eliminated
#1estate_root mismatches,the testnet still crawled: blocks committed only via the slow
GetBlockssync fallback, ~1 block per several seconds, with nodes frequently stuck in
the BFT
Finalizephase.Root cause
In the peer-propose
FinalizeBlockarm, the node already held thefinalized block — it had received the proposal and voted for it, the
hash-match guard confirmed
proposed_block.hash == action.block_hash, andjustificationcarried the 2/3 precommit certificate. But the code appliedit only if the local node was the proposer; otherwise it logged
"waiting for libp2p NewBlock/sync instead of executing peer block",
triggered a sync, and broke. When NewBlock gossip missed (common after a
restart / on a small mesh), the node sat in
Finalizere-requesting a blockit was holding the whole time → stall/crawl.
Fix
Apply the held block locally regardless of proposer, mirroring the
self-propose arm. The hash-match guard already proved it is the canonical
finalized block, and
validate_blockstill re-checks structure + thejustification supermajority before the write. No change to block content or
state_root, so no fork gate — deploy fleet-wide.Validation
Deployed to the 4-validator internal testnet alongside #792: block production
went from a crawl to ~3 blk/s (catching up the backlog), all validators
converged to the same height, and the public RPC returned to 200.
Note
Stacks on #792 (base set to that branch). A benign log artifact remains: the
redundant libp2p receive path can
#1eon a block the finalize path alreadycommitted — non-fatal (committed state_root is identical across nodes), to be
quieted as a follow-up.