From ccd8b9912eb6a1f64be1d23e7c93bde09991df3b Mon Sep 17 00:00:00 2001
From: Felipe Buiras <f.morisan@gmail.com>
Date: Thu, 30 Mar 2023 11:03:03 -0300
Subject: [PATCH] fix: mul before div to avoid precision loss

---
 contracts/DAIInterestRateModelV4.sol | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/contracts/DAIInterestRateModelV4.sol b/contracts/DAIInterestRateModelV4.sol
index 6e1ff9457..643118db9 100644
--- a/contracts/DAIInterestRateModelV4.sol
+++ b/contracts/DAIInterestRateModelV4.sol
@@ -82,8 +82,8 @@ contract DAIInterestRateModelV4 is JumpRateModelV2 {
      */
     function dsrPerBlock() public view returns (uint) {
         return (pot.dsr() - RAY_BASE) // scaled RAY_BASE aka RAY, and includes an extra "ONE" before subtraction
-            / RAY_TO_BASE_SCALE // descale to BASE
             * SECONDS_PER_BLOCK; // seconds per block
+            / RAY_TO_BASE_SCALE // descale to BASE
     }
 
     /**
@@ -91,7 +91,7 @@ contract DAIInterestRateModelV4 is JumpRateModelV2 {
      */
     function poke() public {
         (uint duty, ) = jug.ilks("ETH-B");
-        uint stabilityFeePerBlock = (duty + jug.base() - RAY_BASE) / RAY_TO_BASE_SCALE * SECONDS_PER_BLOCK;
+        uint stabilityFeePerBlock = (duty + jug.base() - RAY_BASE) * SECONDS_PER_BLOCK / RAY_TO_BASE_SCALE;
 
         // We ensure the minimum borrow rate >= DSR / (1 - reserve factor)
         baseRatePerBlock = dsrPerBlock() * BASE / assumedOneMinusReserveFactorMantissa;