fix: add sanity check for intertimAsset == 0 in approveRefund() [sup 9337] (#656)

Author: TamaraRingas

src/router-plus/SuperformRouterPlusAsync.sol

@@ -452,6 +452,8 @@ contract SuperformRouterPlusAsync is ISuperformRouterPlusAsync, BaseSuperformRou
 
         Refund memory r = refunds[routerPlusPayloadId_];
 
+        if (r.interimToken == address(0)) revert INVALID_REFUND_DATA();
+
         approvedRefund[routerPlusPayloadId_] = true;
 
         /// @dev deleting to prevent re-entrancy

test/unit/router-plus/SuperformRouterPlus.t.sol

@@ -2506,6 +2506,12 @@ contract SuperformRouterPlusTest is ProtocolActions {
         SuperformRouterPlusAsync(ROUTER_PLUS_ASYNC_SOURCE).approveRefund(1);
         vm.stopPrank();
 
+        /// @dev testing invalid refund data
+        vm.startPrank(deployer);
+        vm.expectRevert(ISuperformRouterPlusAsync.INVALID_REFUND_DATA.selector);
+        SuperformRouterPlusAsync(ROUTER_PLUS_ASYNC_SOURCE).approveRefund(3);
+        vm.stopPrank();
+
         /// @dev testing valid refund approval
         uint256 balanceBefore = MockERC20(refundToken).balanceOf(deployer);
         uint256 routerBalanceBefore = MockERC20(refundToken).balanceOf(address(ROUTER_PLUS_ASYNC_SOURCE));