Yul interpreter: Introduce expression evaluation maximum nesting depth

This commit is contained in:
Bhargava Shastry
2020-12-04 17:27:03 +01:00
parent 0015e8cd84
commit 32fd692c51
9 changed files with 70 additions and 5 deletions
+13
View File
@@ -247,6 +247,7 @@ void Interpreter::incrementStep()
void ExpressionEvaluator::operator()(Literal const& _literal)
{
incrementStep();
static YulString const trueString("true");
static YulString const falseString("false");
@@ -256,6 +257,7 @@ void ExpressionEvaluator::operator()(Literal const& _literal)
void ExpressionEvaluator::operator()(Identifier const& _identifier)
{
solAssert(m_variables.count(_identifier.name), "");
incrementStep();
setValue(m_variables.at(_identifier.name));
}
@@ -326,6 +328,7 @@ void ExpressionEvaluator::evaluateArgs(
vector<optional<LiteralKind>> const* _literalArguments
)
{
incrementStep();
vector<u256> values;
size_t i = 0;
/// Function arguments are evaluated in reverse.
@@ -341,3 +344,13 @@ void ExpressionEvaluator::evaluateArgs(
m_values = std::move(values);
std::reverse(m_values.begin(), m_values.end());
}
void ExpressionEvaluator::incrementStep()
{
m_nestingLevel++;
if (m_state.maxExprNesting > 0 && m_nestingLevel > m_state.maxExprNesting)
{
m_state.trace.emplace_back("Maximum expression nesting level reached.");
throw ExpressionNestingLimitReached();
}
}