fix(levm): add memory alignment in extcodecopy (#1263)

**Motivation**

Fixes an implementation error found by
[FuzzingLabs](https://github.com/FuzzingLabs) in extcodecopy opcode
implementation.

**Description**

Previously, in EXTCODECOPY the allocated memory size was not aligned to
a multiple of 32 bytes, and was added in, for example, 12 bytes (should
increase in blocks of 32). Now the increases are done in groups of 32.

Closes #1251

crates/vm/levm/src/opcode_handlers/environment.rs

@@ -324,9 +324,13 @@ impl VM {
 
         let bytecode = self.get_account(&address).info.bytecode;
 
-        let new_memory_size = dest_offset.checked_add(size).ok_or(VMError::Internal(
+        let new_memory_size = (((!size).checked_add(1).ok_or(VMError::Internal(
             InternalError::ArithmeticOperationOverflow,
-        ))?;
+        ))?) & 31)
+            .checked_add(size)
+            .ok_or(VMError::Internal(
+                InternalError::ArithmeticOperationOverflow,
+            ))?;
         let current_memory_size = current_call_frame.memory.data.len();
         if current_memory_size < new_memory_size {
             current_call_frame.memory.data.resize(new_memory_size, 0);

crates/vm/levm/tests/edge_case_tests.rs

@@ -132,3 +132,14 @@ fn test_non_compliance_extcodecopy() {
     vm.execute(&mut current_call_frame);
     assert_eq!(current_call_frame.stack.stack.pop().unwrap(), U256::zero());
 }
+
+#[test]
+fn test_non_compliance_extcodecopy_memory_resize() {
+    let mut vm = new_vm_with_bytecode(Bytes::copy_from_slice(&[
+        0x60, 12, 0x5f, 0x5f, 0x5f, 0x3c, 89,
+    ]))
+    .unwrap();
+    let mut current_call_frame = vm.call_frames.pop().unwrap();
+    vm.execute(&mut current_call_frame);
+    assert_eq!(current_call_frame.stack.pop().unwrap(), U256::from(32));
+}