From 0911f907a801d72c0624f58788ba683fbd392ad6 Mon Sep 17 00:00:00 2001
From: eboado <ernesto.boado.moreira@gmail.com>
Date: Sun, 13 Sep 2020 10:08:14 +0200
Subject: [PATCH] Fixes #35

---
 contracts/lendingpool/LendingPool.sol         |  4 ++
 contracts/libraries/logic/ValidationLogic.sol | 16 ++++++++
 test/liquidation-underlying.spec.ts           | 21 ++++++++++
 test/repay-with-collateral.spec.ts            | 38 +++++++++++++++++++
 4 files changed, 79 insertions(+)

diff --git a/contracts/lendingpool/LendingPool.sol b/contracts/lendingpool/LendingPool.sol
index 30a69084..5dfe544f 100644
--- a/contracts/lendingpool/LendingPool.sol
+++ b/contracts/lendingpool/LendingPool.sol
@@ -385,6 +385,8 @@ contract LendingPool is VersionedInitializable, ILendingPool {
     uint256 purchaseAmount,
     bool receiveAToken
   ) external override {
+    ValidationLogic.validateLiquidation(_reserves[collateral], _reserves[asset]);
+    
     address liquidationManager = _addressesProvider.getLendingPoolLiquidationManager();
 
     //solium-disable-next-line
@@ -444,6 +446,8 @@ contract LendingPool is VersionedInitializable, ILendingPool {
     require(!_flashLiquidationLocked, Errors.REENTRANCY_NOT_ALLOWED);
     _flashLiquidationLocked = true;
 
+    ValidationLogic.validateLiquidation(_reserves[collateral], _reserves[principal]);
+
     address liquidationManager = _addressesProvider.getLendingPoolLiquidationManager();
 
     //solium-disable-next-line
diff --git a/contracts/libraries/logic/ValidationLogic.sol b/contracts/libraries/logic/ValidationLogic.sol
index 9be3f828..60d7645c 100644
--- a/contracts/libraries/logic/ValidationLogic.sol
+++ b/contracts/libraries/logic/ValidationLogic.sol
@@ -329,4 +329,20 @@ library ValidationLogic {
     require(premium > 0, Errors.REQUESTED_AMOUNT_TOO_SMALL);
     require(mode <= uint256(ReserveLogic.InterestRateMode.VARIABLE), Errors.INVALID_FLASHLOAN_MODE);
   }
+
+  /**
+   * @dev Validates configurations for liquidation actions, both liquidationCall() and repayWithCollateral()
+   * @param collateralReserve The reserve data of the collateral
+   * @param principalReserve The reserve data of the principal
+   **/
+  function validateLiquidation(
+    ReserveLogic.ReserveData storage collateralReserve,
+    ReserveLogic.ReserveData storage principalReserve
+  ) internal view {
+    require(
+        collateralReserve.configuration.getActive() && 
+        principalReserve.configuration.getActive(), 
+      Errors.NO_ACTIVE_RESERVE
+    );
+  }
 }
diff --git a/test/liquidation-underlying.spec.ts b/test/liquidation-underlying.spec.ts
index 3f2aecbc..076abf88 100644
--- a/test/liquidation-underlying.spec.ts
+++ b/test/liquidation-underlying.spec.ts
@@ -7,6 +7,7 @@ import {makeSuite} from './helpers/make-suite';
 import {ProtocolErrors, RateMode} from '../helpers/types';
 import {calcExpectedStableDebtTokenBalance} from './helpers/utils/calculations';
 import {getUserData} from './helpers/utils/helpers';
+import {parseEther} from 'ethers/lib/utils';
 
 const chai = require('chai');
 
@@ -23,6 +24,26 @@ makeSuite('LendingPool liquidation - liquidator receiving the underlying asset',
     BigNumber.config({DECIMAL_PLACES: 20, ROUNDING_MODE: BigNumber.ROUND_HALF_UP});
   });
 
+  it("It's not possible to liquidate on a non-active collateral or a non active principal", async () => {
+    const {configurator, weth, pool, users, dai} = testEnv;
+    const user = users[1];
+    await configurator.deactivateReserve(weth.address);
+
+    await expect(
+      pool.liquidationCall(weth.address, dai.address, user.address, parseEther('1000'), false)
+    ).to.be.revertedWith('2');
+
+    await configurator.activateReserve(weth.address);
+
+    await configurator.deactivateReserve(dai.address);
+
+    await expect(
+      pool.liquidationCall(weth.address, dai.address, user.address, parseEther('1000'), false)
+    ).to.be.revertedWith('2');
+
+    await configurator.activateReserve(dai.address);
+  });
+
   it('LIQUIDATION - Deposits WETH, borrows DAI', async () => {
     const {dai, weth, users, pool, oracle} = testEnv;
     const depositor = users[0];
diff --git a/test/repay-with-collateral.spec.ts b/test/repay-with-collateral.spec.ts
index faefa403..81d42cbe 100644
--- a/test/repay-with-collateral.spec.ts
+++ b/test/repay-with-collateral.spec.ts
@@ -39,6 +39,44 @@ export const expectRepayWithCollateralEvent = (
 };
 
 makeSuite('LendingPool. repayWithCollateral()', (testEnv: TestEnv) => {
+  it("It's not possible to repayWithCollateral() on a non-active collateral or a non active principal", async () => {
+    const {configurator, weth, pool, users, dai, mockSwapAdapter} = testEnv;
+    const user = users[1];
+    await configurator.deactivateReserve(weth.address);
+
+    await expect(
+      pool
+        .connect(user.signer)
+        .repayWithCollateral(
+          weth.address,
+          dai.address,
+          user.address,
+          parseEther('100'),
+          mockSwapAdapter.address,
+          '0x'
+        )
+    ).to.be.revertedWith('2');
+
+    await configurator.activateReserve(weth.address);
+
+    await configurator.deactivateReserve(dai.address);
+
+    await expect(
+      pool
+        .connect(user.signer)
+        .repayWithCollateral(
+          weth.address,
+          dai.address,
+          user.address,
+          parseEther('100'),
+          mockSwapAdapter.address,
+          '0x'
+        )
+    ).to.be.revertedWith('2');
+
+    await configurator.activateReserve(dai.address);
+  });
+
   it('User 1 provides some liquidity for others to borrow', async () => {
     const {pool, weth, dai, usdc, deployer} = testEnv;