Merge pull request #398 from morpho-org/fix/issue-600

Add checks in ERC20WrapperBundler

src/ERC20WrapperBundler.sol

@@ -23,7 +23,8 @@ abstract contract ERC20WrapperBundler is BaseBundler {
     /// @dev Wraps tokens on behalf of the initiator to make sure they are able to receive and transfer wrapped tokens.
     /// @dev Wrapped tokens must be transferred to the bundler afterwards to perform additional actions.
     /// @dev Initiator must have previously transferred their tokens to the bundler.
-    /// @dev Assumes that `wrapper` implements the `ERC20Wrapper` interface.
+    /// @dev Assumes that `wrapper` implements the `ERC20Wrapper` interface and that the `depositFor` function returns a
+    /// boolean.
     /// @param wrapper The address of the ERC20 wrapper contract.
     /// @param amount The amount of underlying tokens to deposit. Capped at the bundler's balance.
     function erc20WrapperDepositFor(address wrapper, uint256 amount) external payable protected {
@@ -34,12 +35,14 @@ abstract contract ERC20WrapperBundler is BaseBundler {
         require(amount != 0, ErrorsLib.ZERO_AMOUNT);
 
         _approveMaxTo(address(underlying), wrapper);
-        ERC20Wrapper(wrapper).depositFor(initiator(), amount);
+
+        require(ERC20Wrapper(wrapper).depositFor(initiator(), amount), ErrorsLib.DEPOSIT_FAILED);
     }
 
     /// @notice Burns a number of wrapped tokens and withdraws the corresponding number of underlying tokens.
     /// @dev Initiator must have previously transferred their wrapped tokens to the bundler.
-    /// @dev Assumes that `wrapper` implements the `ERC20Wrapper` interface.
+    /// @dev Assumes that `wrapper` implements the `ERC20Wrapper` interface and that the `withdrawTo` function returns a
+    /// boolean.
     /// @param wrapper The address of the ERC20 wrapper contract.
     /// @param account The address receiving the underlying tokens.
     /// @param amount The amount of wrapped tokens to burn. Capped at the bundler's balance.
@@ -50,6 +53,6 @@ abstract contract ERC20WrapperBundler is BaseBundler {
 
         require(amount != 0, ErrorsLib.ZERO_AMOUNT);
 
-        ERC20Wrapper(wrapper).withdrawTo(account, amount);
+        require(ERC20Wrapper(wrapper).withdrawTo(account, amount), ErrorsLib.WITHDRAW_FAILED);
     }
 }

src/libraries/ErrorsLib.sol

@@ -38,6 +38,12 @@ library ErrorsLib {
     /// @dev Thrown when an action ends up minting/burning more shares than a given slippage.
     string internal constant SLIPPAGE_EXCEEDED = "slippage exceeded";
 
+    /// @dev Thrown when a call to depositFor fails.
+    string internal constant DEPOSIT_FAILED = "deposit failed";
+
+    /// @dev Thrown when a call to withdrawTo fails.
+    string internal constant WITHDRAW_FAILED = "withdraw failed";
+
     /* MIGRATION BUNDLERS */
 
     /// @dev Thrown when repaying a CompoundV2 debt returns an error code.

test/forge/ERC20WrapperBundlerLocalTest.sol

@@ -4,7 +4,7 @@ pragma solidity ^0.8.0;
 import {ErrorsLib} from "../../src/libraries/ErrorsLib.sol";
 
 import {ERC20WrapperBundlerMock} from "../../src/mocks/bundlers/ERC20WrapperBundlerMock.sol";
-import {ERC20WrapperMock} from "../../src/mocks/ERC20WrapperMock.sol";
+import {ERC20WrapperMock, ERC20Wrapper} from "../../src/mocks/ERC20WrapperMock.sol";
 
 import "./helpers/LocalTest.sol";
 
@@ -98,4 +98,29 @@ contract ERC20WrapperBundlerBundlerLocalTest is LocalTest {
         vm.expectRevert(bytes(ErrorsLib.UNINITIATED));
         ERC20WrapperBundler(address(bundler)).erc20WrapperWithdrawTo(address(loanWrapper), RECEIVER, amount);
     }
+
+    function testErc20WrapperDepositToFailed(uint256 amount) public {
+        amount = bound(amount, MIN_AMOUNT, MAX_AMOUNT);
+        loanToken.setBalance(address(bundler), amount);
+
+        bundle.push(_erc20WrapperDepositFor(address(loanWrapper), amount));
+
+        vm.mockCall(address(loanWrapper), abi.encodeWithSelector(ERC20Wrapper.depositFor.selector), abi.encode(false));
+
+        vm.expectRevert(bytes(ErrorsLib.DEPOSIT_FAILED));
+        bundler.multicall(bundle);
+    }
+
+    function testErc20WrapperWithdrawToFailed(uint256 amount) public {
+        amount = bound(amount, MIN_AMOUNT, MAX_AMOUNT);
+        loanWrapper.setBalance(address(bundler), amount);
+        loanToken.setBalance(address(loanWrapper), amount);
+
+        bundle.push(_erc20WrapperWithdrawTo(address(loanWrapper), RECEIVER, amount));
+
+        vm.mockCall(address(loanWrapper), abi.encodeWithSelector(ERC20Wrapper.withdrawTo.selector), abi.encode(false));
+
+        vm.expectRevert(bytes(ErrorsLib.WITHDRAW_FAILED));
+        bundler.multicall(bundle);
+    }
 }