Fix absolutely potato brain bug

src/lib/Collections/BinaryData.vala

@@ -288,7 +288,7 @@ namespace Invercargill {
             if(data.length == 0) {
                 throw new BinaryDataReadError.EMPTY_READ("Encounterd zero-length data object");
             }
-            if(amount > data.length) {
+            if(data.length > amount) {
                 throw new BinaryDataReadError.BUFFER_OVERFLOW("Encountered more data than requested");
             }