From 02be7fe772e24aa47d5b4008a4cc6a33b7a6910f Mon Sep 17 00:00:00 2001
From: Rubilmax <rmilon@gmail.com>
Date: Tue, 26 Sep 2023 17:56:57 +0200
Subject: [PATCH 1/2] refactor(reallocate): use sum of assets

---
 src/MetaMorpho.sol          | 28 +++++++++++++++++++++-------
 src/libraries/ErrorsLib.sol |  2 ++
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/MetaMorpho.sol b/src/MetaMorpho.sol
index af32f5b2..6f0bb335 100644
--- a/src/MetaMorpho.sol
+++ b/src/MetaMorpho.sol
@@ -283,22 +283,29 @@ contract MetaMorpho is ERC4626, ERC20Permit, Ownable2Step, Multicall, IMetaMorph
         external
         onlyAllocator
     {
-        uint256 balanceBefore = ERC20(asset()).balanceOf(address(this));
-
+        uint256 totalWithdrawn;
         uint256 nbWithdrawn = withdrawn.length;
 
         for (uint256 i; i < nbWithdrawn; ++i) {
             MarketAllocation memory allocation = withdrawn[i];
 
-            MORPHO.withdraw(allocation.marketParams, allocation.assets, allocation.shares, address(this), address(this));
+            (uint256 withdrawnAssets,) = MORPHO.withdraw(
+                allocation.marketParams, allocation.assets, allocation.shares, address(this), address(this)
+            );
+
+            totalWithdrawn += withdrawnAssets;
         }
 
+        uint256 totalSupplied;
         uint256 nbSupplied = supplied.length;
 
         for (uint256 i; i < nbSupplied; ++i) {
             MarketAllocation memory allocation = supplied[i];
 
-            MORPHO.supply(allocation.marketParams, allocation.assets, allocation.shares, address(this), hex"");
+            (uint256 suppliedAssets,) =
+                MORPHO.supply(allocation.marketParams, allocation.assets, allocation.shares, address(this), hex"");
+
+            totalSupplied += suppliedAssets;
 
             require(
                 _supplyBalance(allocation.marketParams) <= config[allocation.marketParams.id()].cap,
@@ -306,10 +313,17 @@ contract MetaMorpho is ERC4626, ERC20Permit, Ownable2Step, Multicall, IMetaMorph
             );
         }
 
-        uint256 balanceAfter = ERC20(asset()).balanceOf(address(this));
+        if (totalWithdrawn > totalSupplied) {
+            idle += totalWithdrawn - totalSupplied;
+        } else {
+            uint256 idleSupplied = totalSupplied - totalWithdrawn;
+            require(idle >= idleSupplied, ErrorsLib.INSUFFICIENT_IDLE);
 
-        if (balanceAfter > balanceBefore) idle += balanceAfter - balanceBefore;
-        else idle -= balanceBefore - balanceAfter;
+            unchecked {
+                // Underflow not possible: idle >= idleSupplied.
+                idle -= idleSupplied;
+            }
+        }
     }
 
     /* EXTERNAL */
diff --git a/src/libraries/ErrorsLib.sol b/src/libraries/ErrorsLib.sol
index a593ec11..fb5730c0 100644
--- a/src/libraries/ErrorsLib.sol
+++ b/src/libraries/ErrorsLib.sol
@@ -43,4 +43,6 @@ library ErrorsLib {
     string internal constant MAX_QUEUE_SIZE_EXCEEDED = "max queue size exceeded";
 
     string internal constant ZERO_FEE_RECIPIENT = "fee recipient is zero";
+
+    string internal constant INSUFFICIENT_IDLE = "insufficient idle liquidity";
 }

From ff9198428944dfa8f05a1b01cd205d2be98ab859 Mon Sep 17 00:00:00 2001
From: Rubilmax <rmilon@gmail.com>
Date: Thu, 28 Sep 2023 14:18:25 +0200
Subject: [PATCH 2/2] refactor(metamorpho): remove overwhelming unchecked

---
 src/MetaMorpho.sol | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/MetaMorpho.sol b/src/MetaMorpho.sol
index 0c518b4b..81f99597 100644
--- a/src/MetaMorpho.sol
+++ b/src/MetaMorpho.sol
@@ -319,10 +319,7 @@ contract MetaMorpho is ERC4626, ERC20Permit, Ownable2Step, Multicall, IMetaMorph
             uint256 idleSupplied = totalSupplied - totalWithdrawn;
             require(idle >= idleSupplied, ErrorsLib.INSUFFICIENT_IDLE);
 
-            unchecked {
-                // Underflow not possible: idle >= idleSupplied.
-                idle -= idleSupplied;
-            }
+            idle -= idleSupplied;
         }
     }