feat: rearrange requires to ensure no division by zero

morpho-org · Oct 5, 2024 · de168dd · de168dd
1 parent bdcffe9
commit de168dd
Showing 1 changed file with 5 additions and 5 deletions.
diff --git a/src/PreLiquidation.sol b/src/PreLiquidation.sol
@@ -141,13 +141,13 @@ contract PreLiquidation is IPreLiquidation, IMorphoRepayCallback {
         uint256 collateralPrice = IOracle(PRE_LIQUIDATION_ORACLE).price();
         uint256 collateralQuoted = uint256(position.collateral).mulDivDown(collateralPrice, ORACLE_PRICE_SCALE);
         uint256 borrowed = uint256(position.borrowShares).toAssetsUp(market.totalBorrowAssets, market.totalBorrowShares);
-        uint256 ltv = borrowed.wDivUp(collateralQuoted);
-
-        // The following require is equivalent to checking that borrowed > collateralQuoted.wMulDown(PRE_LLTV).
-        require(ltv > PRE_LLTV, ErrorsLib.NotPreLiquidatablePosition());
 
-        require(ltv <= LLTV, ErrorsLib.LiquidatablePosition());
+        // The following require is equivalent to checking that ltv > PRE_LLTV.
+        require(borrowed > collateralQuoted.wMulDown(PRE_LLTV), ErrorsLib.NotPreLiquidatablePosition());
+        require(borrowed <= collateralQuoted.wMulDown(LLTV), ErrorsLib.LiquidatablePosition());
 
+        // The two preceding requires ensures that collateralQuoted is different from zero.
+        uint256 ltv = borrowed.wDivUp(collateralQuoted);
         uint256 preLIF = (ltv - PRE_LLTV).wDivDown(LLTV - PRE_LLTV).wMulDown(PRE_LIF_2 - PRE_LIF_1) + PRE_LIF_1;
 
         if (seizedAssets > 0) {