Fix: add overflow checking and test codes for cover edge cases (#458)

* test: add testcase for cover small withdrawal case

* test: add test case for CreatePool

* fix: refactor and optimize depleted pool validation

* feat: add overflow checking logic

* chore: add testcase and remove comments

* test: add test code for big deposit

* fix: apply PR suggestions

* fix: add overflow checking logic and test cases

Co-authored-by: Hanjun Kim <hallazzang@gmail.com>
Co-authored-by: typark391 <86215716+typark391@users.noreply.github.com>

CHANGELOG.md

@@ -35,12 +35,14 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
-## v1.4.x - 2021.10.xx
+## [Unreleased]
+
+## [v1.4.1](https://github.com/tendermint/liquidity/releases) - 2021.10.25
 
 * [\#455](https://github.com/tendermint/liquidity/pull/455) (sdk) Bump SDK version to [v0.44.2](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.44.2)
 * [\#446](https://github.com/tendermint/liquidity/pull/446) Fix: Pool Coin Decimal Truncation During Deposit
+* [\#448](https://github.com/tendermint/liquidity/pull/448) Fix: add overflow checking and test codes for cover edge cases
 
-## [Unreleased]
 
 ## [v1.4.0](https://github.com/tendermint/liquidity/releases/tag/v1.4.0) - 2021.09.07
 

x/liquidity/keeper/batch.go

@@ -236,7 +236,14 @@ func (k Keeper) WithdrawWithinBatch(ctx sdk.Context, msg *types.MsgWithdrawWithi
 
 // In order to deal with the batch at the same time, the coins of msgs are deposited in escrow.
 func (k Keeper) SwapWithinBatch(ctx sdk.Context, msg *types.MsgSwapWithinBatch, orderExpirySpanHeight int64) (*types.SwapMsgState, error) {
-	if err := k.ValidateMsgSwapWithinBatch(ctx, *msg); err != nil {
+	pool, found := k.GetPool(ctx, msg.PoolId)
+	if !found {
+		return nil, types.ErrPoolNotExists
+	}
+	if k.IsDepletedPool(ctx, pool) {
+		return nil, types.ErrDepletedPool
+	}
+	if err := k.ValidateMsgSwapWithinBatch(ctx, *msg, pool); err != nil {
 		return nil, err
 	}
 	poolBatch, found := k.GetPoolBatch(ctx, msg.PoolId)

x/liquidity/keeper/liquidity_pool.go

@@ -245,12 +245,18 @@ func (k Keeper) ExecuteDeposit(ctx sdk.Context, msg types.DepositMsgState, batch
 	depositCoinA := depositCoins[0]
 	depositCoinB := depositCoins[1]
 
-	poolCoinTotalSupply := k.GetPoolCoinTotalSupply(ctx, pool)
+	poolCoinTotalSupply := k.GetPoolCoinTotalSupply(ctx, pool).ToDec()
+	if err := types.CheckOverflowWithDec(poolCoinTotalSupply, depositCoinA.Amount.ToDec()); err != nil {
+		return err
+	}
+	if err := types.CheckOverflowWithDec(poolCoinTotalSupply, depositCoinB.Amount.ToDec()); err != nil {
+		return err
+	}
 	poolCoinMintAmt := sdk.MinDec(
-		poolCoinTotalSupply.ToDec().MulTruncate(depositCoinA.Amount.ToDec()).QuoTruncate(lastReserveCoinA.Amount.ToDec()),
-		poolCoinTotalSupply.ToDec().MulTruncate(depositCoinB.Amount.ToDec()).QuoTruncate(lastReserveCoinB.Amount.ToDec()),
+		poolCoinTotalSupply.MulTruncate(depositCoinA.Amount.ToDec()).QuoTruncate(lastReserveCoinA.Amount.ToDec()),
+		poolCoinTotalSupply.MulTruncate(depositCoinB.Amount.ToDec()).QuoTruncate(lastReserveCoinB.Amount.ToDec()),
 	)
-	mintRate := poolCoinMintAmt.TruncateDec().QuoTruncate(poolCoinTotalSupply.ToDec())
+	mintRate := poolCoinMintAmt.TruncateDec().QuoTruncate(poolCoinTotalSupply)
 	acceptedCoins := sdk.NewCoins(
 		sdk.NewCoin(depositCoins[0].Denom, lastReserveCoinA.Amount.ToDec().Mul(mintRate).TruncateInt()),
 		sdk.NewCoin(depositCoins[1].Denom, lastReserveCoinB.Amount.ToDec().Mul(mintRate).TruncateInt()),
@@ -301,7 +307,7 @@ func (k Keeper) ExecuteDeposit(ctx sdk.Context, msg types.DepositMsgState, batch
 		afterReserveCoinA := afterReserveCoins[0].Amount
 		afterReserveCoinB := afterReserveCoins[1].Amount
 
-		MintingPoolCoinsInvariant(poolCoinTotalSupply, mintPoolCoin.Amount, depositCoinA.Amount, depositCoinB.Amount,
+		MintingPoolCoinsInvariant(poolCoinTotalSupply.TruncateInt(), mintPoolCoin.Amount, depositCoinA.Amount, depositCoinB.Amount,
 			lastReserveCoinA.Amount, lastReserveCoinB.Amount, refundedCoinA.Amount, refundedCoinB.Amount)
 		DepositInvariant(lastReserveCoinA.Amount, lastReserveCoinB.Amount, depositCoinA.Amount, depositCoinB.Amount,
 			afterReserveCoinA, afterReserveCoinB, refundedCoinA.Amount, refundedCoinB.Amount)
@@ -378,6 +384,12 @@ func (k Keeper) ExecuteWithdrawal(ctx sdk.Context, msg types.WithdrawMsgState, b
 	} else {
 		// Calculate withdraw amount of respective reserve coin considering fees and pool coin's totally supply
 		for _, reserveCoin := range reserveCoins {
+			if err := types.CheckOverflow(reserveCoin.Amount, msg.Msg.PoolCoin.Amount); err != nil {
+				return err
+			}
+			if err := types.CheckOverflow(reserveCoin.Amount.Mul(msg.Msg.PoolCoin.Amount).ToDec().TruncateInt(), poolCoinTotalSupply); err != nil {
+				return err
+			}
 			// WithdrawAmount = ReserveAmount * PoolCoinAmount * WithdrawFeeProportion / TotalSupply
 			withdrawAmtWithFee := reserveCoin.Amount.Mul(msg.Msg.PoolCoin.Amount).ToDec().TruncateInt().Quo(poolCoinTotalSupply)
 			withdrawAmt := reserveCoin.Amount.Mul(msg.Msg.PoolCoin.Amount).ToDec().MulTruncate(withdrawProportion).TruncateInt().Quo(poolCoinTotalSupply)
@@ -770,21 +782,12 @@ func (k Keeper) ValidateMsgWithdrawWithinBatch(ctx sdk.Context, msg types.MsgWit
 }
 
 // ValidateMsgSwapWithinBatch validates MsgSwapWithinBatch.
-func (k Keeper) ValidateMsgSwapWithinBatch(ctx sdk.Context, msg types.MsgSwapWithinBatch) error {
-	pool, found := k.GetPool(ctx, msg.PoolId)
-	if !found {
-		return types.ErrPoolNotExists
-	}
-
+func (k Keeper) ValidateMsgSwapWithinBatch(ctx sdk.Context, msg types.MsgSwapWithinBatch, pool types.Pool) error {
 	denomA, denomB := types.AlphabeticalDenomPair(msg.OfferCoin.Denom, msg.DemandCoinDenom)
 	if denomA != pool.ReserveCoinDenoms[0] || denomB != pool.ReserveCoinDenoms[1] {
 		return types.ErrNotMatchedReserveCoin
 	}
 
-	if k.IsDepletedPool(ctx, pool) {
-		return types.ErrDepletedPool
-	}
-
 	params := k.GetParams(ctx)
 
 	// can not exceed max order ratio  of reserve coins that can be ordered at a order
@@ -800,6 +803,10 @@ func (k Keeper) ValidateMsgSwapWithinBatch(ctx sdk.Context, msg types.MsgSwapWit
 		return types.ErrBadOfferCoinFee
 	}
 
+	if err := types.CheckOverflowWithDec(msg.OfferCoin.Amount.ToDec(), msg.OrderPrice); err != nil {
+		return err
+	}
+
 	if !msg.OfferCoinFee.Equal(types.GetOfferCoinFee(msg.OfferCoin, params.SwapFeeRate)) {
 		return types.ErrBadOfferCoinFee
 	}