From fc185fdc61ebaaf62a5fcf61d2bd8636ff11283c Mon Sep 17 00:00:00 2001
From: Barry Gitarts <bgitarts@gmail.com>
Date: Sun, 14 Apr 2019 09:28:07 -0400
Subject: [PATCH] safemath in calculation of interest owed

---
 contracts/subscription.sol | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/contracts/subscription.sol b/contracts/subscription.sol
index 9dcbbd9..d499676 100644
--- a/contracts/subscription.sol
+++ b/contracts/subscription.sol
@@ -106,7 +106,9 @@ contract Subscription {
     function getInterestOwed(uint256 amountOwed) view public returns (uint256) {
       uint256 totalAmount = compound.getSupplyBalance(address(this), daiAddress);
       uint256 totalInterest = totalAmount - totalBalances;
-      uint256 interestOwed = totalInterest * amountOwed / totalBalances;
+      if (amountOwed == totalBalances) return totalInterest;
+      uint256 totalOwned = totalInterest * amountOwed;
+      uint256 interestOwed = totalOwned.div(totalBalances);
       return interestOwed;
     }