vocdoni / vocdoni-node / 34843966668

65%

main: 65%

Build Type

Pull #1454

github

Committed by altergui

Commit Message

fix(vochain/ist): guard uint32 underflow in score gap and grace-period check

`updateValidatorScore` computes `gap := height - windowStart` and
`height - since` as bare `uint32` subtractions. If the window boundary
(TreeExtra `vldSW/`) or the inactive-since marker (TreeExtra `vldIS/`)
ever lands ahead of the current chain height — after a `cometbft
rollback`, or a chain restart whose `InitialHeight` is below a
previously recorded height — both subtractions wrap to ~4e9. The
downstream effect on the grace-period check is a validator evicted
with no grace at all; on the score branch the ratio collapses to 0
and every validator decays each period.

Guard both boundaries against underflow:

- gap: `if windowStart >= height { gap = updatePowerPeriod }`.
- windowVotes: `if v.Votes >= votesAtStart { windowVotes = v.Votes -
  votesAtStart }` (paired safety when the lifetime counter has
  regressed below the recorded boundary).
- eviction: extend the case guard with `height >= since` so the
  grace-period window is only evaluated on well-ordered inputs.

Both new tests fail against the pre-guard code:
- TestNoEvictionWhenInactiveSinceAheadOfHeight: 4 validators marked at
  height 10_000, chain rolled back to 100 — pre-guard evicts the first
  visited validator via the underflow; with the guard, all four
  survive and `DrainRemovedPubKeys` is empty.
- TestScoreGapDoesNotWrapWhenWindowStartAheadOfHeight: 4 validators
  with `vldSW/` boundary at height 10_000, chain rolled back to 100 —
  pre-guard decays power from 500 to 450 via the wrap-induced
  newScore==0 branch; with the guard, gap falls back to
  updatePowerPeriod and power climbs to 510.

Fixes argos review finding 9 on PR#1454.

Pull Request Pull Request #1454: feat(vochain/ist): rework validator voting-power dynamics

Coverage Stats

143 of 176 new or added lines in 4 files covered. (81.25%)

2 existing lines in 2 files now uncovered.

18587 of 28695 relevant lines covered (64.77%)

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