fix: changed conditions of the exposure ceiling

contracts/protocol/lendingpool/LendingPool.sol

@@ -289,7 +289,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
     if (useAsCollateral) {
       emit ReserveUsedAsCollateralEnabled(asset, msg.sender);
     } else {
-      ValidationLogic.validateWithdrawCollateral(
+      ValidationLogic.validateHFAndExposureCap(
         asset,
         msg.sender,
         _reserves,
@@ -497,7 +497,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
       totalDebtETH,
       ltv,
       currentLiquidationThreshold,
-      healthFactor
+      healthFactor,
     ) = GenericLogic.getUserAccountData(
       user,
       _reserves,
@@ -629,7 +629,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
 
       if (fromConfig.isUsingAsCollateral(reserveId)) {
         if (fromConfig.isBorrowingAny()) {
-          ValidationLogic.validateWithdrawCollateral(
+          ValidationLogic.validateHFAndExposureCap(
             asset,
             from,
             _reserves,
@@ -877,7 +877,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
 
     if (userConfig.isUsingAsCollateral(reserve.id)) {
       if (userConfig.isBorrowingAny()) {
-        ValidationLogic.validateWithdrawCollateral(
+        ValidationLogic.validateHFAndExposureCap(
           asset,
           msg.sender,
           _reserves,

contracts/protocol/libraries/logic/GenericLogic.sol

@@ -34,6 +34,7 @@ library GenericLogic {
     uint256 userBalance;
     uint256 userBalanceETH;
     uint256 userDebt;
+    uint256 userStableDebt;
     uint256 userDebtETH;
     uint256 decimals;
     uint256 ltv;
@@ -43,6 +44,7 @@ library GenericLogic {
     uint256 totalCollateralInETH;
     uint256 totalDebtInETH;
     uint256 avgLtv;
+    uint256 avgUncappedLtv;
     uint256 avgLiquidationThreshold;
     uint256 reservesLength;
     uint256 normalizedIncome;
@@ -65,7 +67,7 @@ library GenericLogic {
    * @param userConfig The configuration of the user
    * @param reserves The list of the available reserves
    * @param oracle The price oracle address
-   * @return The total collateral and total debt of the user in ETH, the avg ltv, liquidation threshold and the HF
+   * @return The total collateral and total debt of the user in ETH, the avg ltv, liquidation threshold, the HF and the uncapped avg ltv (without exposure ceiling)
    **/
   function calculateUserAccountData(
     address user,
@@ -82,13 +84,14 @@ library GenericLogic {
       uint256,
       uint256,
       uint256,
+      uint256,
       uint256
     )
   {
     CalculateUserAccountDataVars memory vars;
 
     if (userConfig.isEmpty()) {
-      return (0, 0, 0, 0, uint256(-1));
+      return (0, 0, 0, 0, uint256(-1), 0);
     }
     for (vars.i = 0; vars.i < reservesCount; vars.i++) {
       if (!userConfig.isUsingAsCollateralOrBorrowing(vars.i)) {
@@ -131,13 +134,17 @@ library GenericLogic {
           vars.exposureCap != 0 &&
           vars.aTokenSupply.div(10**vars.decimals) > vars.exposureCap;
 
-        vars.avgLtv = vars.avgLtv.add(vars.exposureCapCrossed ? 0 : vars.userBalanceETH.mul(vars.ltv));
+        vars.avgLtv = vars.avgLtv.add(
+          vars.exposureCapCrossed ? 0 : vars.userBalanceETH.mul(vars.ltv)
+        );
+        vars.avgUncappedLtv = vars.avgUncappedLtv.add(vars.userBalanceETH.mul(vars.ltv));
         vars.avgLiquidationThreshold = vars.avgLiquidationThreshold.add(
           vars.userBalanceETH.mul(vars.liquidationThreshold)
         );
       }
 
       if (userConfig.isBorrowing(vars.i)) {
+        vars.userStableDebt = IERC20(currentReserve.stableDebtTokenAddress).balanceOf(user);
         vars.userDebt = IScaledBalanceToken(currentReserve.variableDebtTokenAddress)
           .scaledBalanceOf(user);
 
@@ -145,16 +152,16 @@ library GenericLogic {
           vars.normalizedDebt = currentReserve.getNormalizedDebt();
           vars.userDebt = vars.userDebt.rayMul(vars.normalizedDebt);
         }
-
+        vars.userDebt = vars.userDebt.add(vars.userStableDebt);
-        vars.userDebt = vars.userDebt.add(
-          IERC20(currentReserve.stableDebtTokenAddress).balanceOf(user)
-        );
         vars.userDebtETH = vars.assetPrice.mul(vars.userDebt).div(vars.assetUnit);
         vars.totalDebtInETH = vars.totalDebtInETH.add(vars.userDebtETH);
       }
     }
 
     vars.avgLtv = vars.totalCollateralInETH > 0 ? vars.avgLtv.div(vars.totalCollateralInETH) : 0;
+    vars.avgUncappedLtv = vars.totalCollateralInETH > 0
+      ? vars.avgUncappedLtv.div(vars.totalCollateralInETH)
+      : 0;
     vars.avgLiquidationThreshold = vars.totalCollateralInETH > 0
       ? vars.avgLiquidationThreshold.div(vars.totalCollateralInETH)
       : 0;
@@ -169,7 +176,8 @@ library GenericLogic {
       vars.totalDebtInETH,
       vars.avgLtv,
       vars.avgLiquidationThreshold,
-      vars.healthFactor
+      vars.healthFactor,
+      vars.avgUncappedLtv
     );
   }
 
@@ -239,6 +247,7 @@ library GenericLogic {
       uint256,
       uint256,
       uint256,
+      uint256,
       uint256
     )
   {

contracts/protocol/libraries/logic/ValidationLogic.sol

@@ -185,7 +185,7 @@ library ValidationLogic {
       vars.userBorrowBalanceETH,
       vars.currentLtv,
       vars.currentLiquidationThreshold,
-      vars.healthFactor
+      vars.healthFactor,
     ) = GenericLogic.calculateUserAccountData(
       userAddress,
       reservesData,
@@ -263,7 +263,7 @@ library ValidationLogic {
     address onBehalfOf,
     uint256 stableDebt,
     uint256 variableDebt
-  ) internal view {
+  ) external view {
     (bool isActive, , , , bool isPaused) = reserveCache.reserveConfiguration.getFlagsMemory();
     require(isActive, Errors.VL_NO_ACTIVE_RESERVE);
     require(!isPaused, Errors.VL_RESERVE_PAUSED);
@@ -469,7 +469,7 @@ library ValidationLogic {
       return (uint256(Errors.CollateralManagerErrors.PAUSED_RESERVE), Errors.VL_RESERVE_PAUSED);
     }
 
-    (, , , , vars.healthFactor) = GenericLogic.calculateUserAccountData(
+    (, , , , vars.healthFactor, ) = GenericLogic.calculateUserAccountData(
       user,
       reservesData,
       userConfig,
@@ -508,7 +508,7 @@ library ValidationLogic {
   }
 
   /**
-   * @dev Validates the health factor of a user
+   * @dev Validates the health factor of a user and the exposure cap for the asset being withdrawn
    * @param from The user from which the aTokens are being transferred
    * @param reservesData The state of all the reserves
    * @param userConfig The state of the user for the specific reserve
@@ -516,7 +516,7 @@ library ValidationLogic {
    * @param reservesCount The number of available reserves
    * @param oracle The price oracle
    */
-  function validateWithdrawCollateral(
+  function validateHFAndExposureCap(
     address collateral,
     address from,
     mapping(address => DataTypes.ReserveData) storage reservesData,
@@ -526,7 +526,7 @@ library ValidationLogic {
     address oracle
   ) external view {
     DataTypes.ReserveData memory reserve = reservesData[collateral];
-    (, , uint256 ltv, uint256 liquidationThreshold, uint256 healthFactor) =
+    (, , uint256 ltv, uint256 liquidationThreshold, uint256 healthFactor, uint256 uncappedLtv) =
       GenericLogic.calculateUserAccountData(
         from,
         reservesData,
@@ -536,28 +536,22 @@ library ValidationLogic {
         oracle
       );
 
-    uint256 exposureCap = reserve.configuration.getExposureCapMemory();
-    uint256 totalSupplyAtoken = IERC20(reserve.aTokenAddress).totalSupply();
-    (, , , uint256 reserveDecimals, ) = reserve.configuration.getParamsMemory();
 
     require(
       healthFactor >= GenericLogic.HEALTH_FACTOR_LIQUIDATION_THRESHOLD,
       Errors.VL_HEALTH_FACTOR_LOWER_THAN_LIQUIDATION_THRESHOLD
     );
 
-    // exposureCap == 0 means no cap => can withdraw
+    uint256 exposureCap = reserve.configuration.getExposureCapMemory();
-    // ltv > liquidationThreshold means that there is enough collateral margin => can withdraw
+
-    // ltv == 0 means all current collaterals have exceeded the exposure cap => can withdraw
+    if (exposureCap != 0) {
-    // last means that for this asset the cap is not yet exceeded => can withdraw
+      if (ltv < uncappedLtv) {
-    // else this means the user is trying to withdraw a collateral that has exceeded the exposure cap, and that it
+        uint256 totalSupplyAtoken = IERC20(reserve.aTokenAddress).totalSupply();
-    // as other collaterals available to withdraw: he must withdraw from other collateral reserves first
+        (, , , uint256 reserveDecimals, ) = reserve.configuration.getParamsMemory();
-    require(
+        bool isAssetCapped = totalSupplyAtoken.div(10**reserveDecimals) >= exposureCap;
-      exposureCap == 0 ||
+        require(isAssetCapped, Errors.VL_COLLATERAL_EXPOSURE_CAP_EXCEEDED);
-        ltv > liquidationThreshold ||
+      }
-        ltv == 0 ||
+    }
-        totalSupplyAtoken.div(10**reserveDecimals) < exposureCap,
-      Errors.VL_COLLATERAL_EXPOSURE_CAP_EXCEEDED
-    );
   }
 
   /**