Fix zero-length slice taint bug (#43)

GNSPS · Jan 7, 2021 · e470a89 · e470a89
1 parent 889455e
commit e470a89
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Showing 3 changed files with 5,860 additions and 21 deletions.
diff --git a/contracts/BytesLib.sol b/contracts/BytesLib.sol
@@ -284,6 +284,9 @@ library BytesLib {
             //if we want a zero-length slice let's just return a zero-length array
             default {
                 tempBytes := mload(0x40)
+                //zero out the 32 bytes slice we are about to return
+                //we need to do it because Solidity does not garbage collect
+                mstore(tempBytes, 0)
 
                 mstore(0x40, add(tempBytes, 0x20))
             }