go/staking/api: Sanity check staking reward threshold

Author: peternose

.changelog/6541.trivial.md

@@ -555,15 +555,16 @@ func (es *EpochSigning) Update(signingEntities []signature.PublicKey) error {
 
 func (es *EpochSigning) EligibleEntities(thresholdNumerator, thresholdDenominator uint64) ([]signature.PublicKey, error) {
 	var eligibleEntities []signature.PublicKey
-	if es.Total > math.MaxUint64/thresholdNumerator {
+	if thresholdNumerator != 0 && es.Total > math.MaxUint64/thresholdNumerator {
 		return nil, fmt.Errorf("overflow in total blocks, total=%d", es.Total)
 	}
 	thresholdPremultiplied := es.Total * thresholdNumerator
 	for entityID, count := range es.ByEntity {
-		if count > math.MaxUint64/thresholdDenominator {
+		if thresholdDenominator != 0 && count > math.MaxUint64/thresholdDenominator {
 			return nil, fmt.Errorf("entity %s: overflow in threshold comparison, count=%d", entityID, count)
 		}
-		if count*thresholdDenominator < thresholdPremultiplied {
+		entityThreshold := count * thresholdDenominator
+		if entityThreshold < thresholdPremultiplied {
 			continue
 		}
 		eligibleEntities = append(eligibleEntities, entityID)

go/consensus/cometbft/apps/staking/state/state.go

@@ -1235,17 +1235,21 @@ type ConsensusParameters struct {
 	// 1 token = 10**TokenValueExponent base units.
 	TokenValueExponent uint8 `json:"token_value_exponent,omitempty"`
 
-	Thresholds                        map[ThresholdKind]quantity.Quantity `json:"thresholds,omitempty"`
-	DebondingInterval                 beacon.EpochTime                    `json:"debonding_interval,omitempty"`
-	RewardSchedule                    []RewardStep                        `json:"reward_schedule,omitempty"`
-	SigningRewardThresholdNumerator   uint64                              `json:"signing_reward_threshold_numerator,omitempty"`
-	SigningRewardThresholdDenominator uint64                              `json:"signing_reward_threshold_denominator,omitempty"`
-	CommissionScheduleRules           CommissionScheduleRules             `json:"commission_schedule_rules,omitempty"`
-	Slashing                          map[SlashReason]Slash               `json:"slashing,omitempty"`
-	GasCosts                          transaction.Costs                   `json:"gas_costs,omitempty"`
-	MinDelegationAmount               quantity.Quantity                   `json:"min_delegation"`
-	MinTransferAmount                 quantity.Quantity                   `json:"min_transfer"`
-	MinTransactBalance                quantity.Quantity                   `json:"min_transact_balance"`
+	Thresholds        map[ThresholdKind]quantity.Quantity `json:"thresholds,omitempty"`
+	DebondingInterval beacon.EpochTime                    `json:"debonding_interval,omitempty"`
+	RewardSchedule    []RewardStep                        `json:"reward_schedule,omitempty"`
+	// SigningRewardThresholdNumerator is the numerator of the threshold used for
+	// block signing rewards.
+	SigningRewardThresholdNumerator uint64 `json:"signing_reward_threshold_numerator,omitempty"`
+	// SigningRewardThresholdDenominator is the denominator of the threshold used for
+	// block signing rewards. If the denominator is zero, the threshold is treated as zero.
+	SigningRewardThresholdDenominator uint64                  `json:"signing_reward_threshold_denominator,omitempty"`
+	CommissionScheduleRules           CommissionScheduleRules `json:"commission_schedule_rules,omitempty"`
+	Slashing                          map[SlashReason]Slash   `json:"slashing,omitempty"`
+	GasCosts                          transaction.Costs       `json:"gas_costs,omitempty"`
+	MinDelegationAmount               quantity.Quantity       `json:"min_delegation"`
+	MinTransferAmount                 quantity.Quantity       `json:"min_transfer"`
+	MinTransactBalance                quantity.Quantity       `json:"min_transact_balance"`
 
 	DisableTransfers       bool             `json:"disable_transfers,omitempty"`
 	DisableDelegation      bool             `json:"disable_delegation,omitempty"`

go/staking/api/api.go

@@ -64,6 +64,11 @@ func (p *ConsensusParameters) SanityCheck() error {
 		prevUntil = step.Until
 	}
 
+	// Signing reward threshold must be a valid fraction between 0 and 1.
+	if p.SigningRewardThresholdNumerator > p.SigningRewardThresholdDenominator {
+		return fmt.Errorf("signing reward threshold numerator must be less than or equal to denominator")
+	}
+
 	return nil
 }