cerc-io/solidity
11
0
Fork 0
mirror of https://github.com/ethereum/solidity synced 2023-10-03 13:03:40 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Only allow access to local variables and only if they have a stack size of one.

Browse Source
This commit is contained in:
chriseth
2017-04-25 16:49:04 +02:00
parent f19e6a09a7
commit dfaab73efe
3 changed files with 53 additions and 63 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libsolidity/codegen/ContractCompiler.cpp
+14 -34
View File
@@ -557,33 +557,16 @@ bool ContractCompiler::visit(InlineAssembly const& _inlineAssembly)
else if (auto variable = dynamic_cast<VariableDeclaration const*>(decl))
{
solAssert(!variable->isConstant(), "");
if (m_context.isLocalVariable(variable))
{
int stackDiff = _assembly.deposit() - m_context.baseStackOffsetOfVariable(*variable);
if (stackDiff < 1 || stackDiff > 16)
BOOST_THROW_EXCEPTION(
CompilerError() <<
errinfo_sourceLocation(_inlineAssembly.location()) <<
errinfo_comment("Stack too deep, try removing local variables.")
);
for (unsigned i = 0; i < variable->type()->sizeOnStack(); ++i)
_assembly.append(dupInstruction(stackDiff));
}
else
{
solAssert(m_context.isStateVariable(variable), "Invalid variable type.");
auto const& location = m_context.storageLocationOfVariable(*variable);
if (!variable->type()->isValueType())
{
solAssert(location.second == 0, "Intra-slot offest assumed to be zero.");
_assembly.append(location.first);
}
else
{
_assembly.append(location.first);
_assembly.append(u256(location.second));
}
}
solAssert(m_context.isLocalVariable(variable), "");
int stackDiff = _assembly.deposit() - m_context.baseStackOffsetOfVariable(*variable);
if (stackDiff < 1 || stackDiff > 16)
BOOST_THROW_EXCEPTION(
CompilerError() <<
errinfo_sourceLocation(_inlineAssembly.location()) <<
errinfo_comment("Stack too deep, try removing local variables.")
);
solAssert(variable->type()->sizeOnStack() == 1, "");
_assembly.append(dupInstruction(stackDiff));
}
else if (auto contract = dynamic_cast<ContractDefinition const*>(decl))
{
@@ -602,19 +585,16 @@ bool ContractCompiler::visit(InlineAssembly const& _inlineAssembly)
!!variable && m_context.isLocalVariable(variable),
"Can only assign to stack variables in inline assembly."
);
unsigned size = variable->type()->sizeOnStack();
int stackDiff = _assembly.deposit() - m_context.baseStackOffsetOfVariable(*variable) - size;
solAssert(variable->type()->sizeOnStack() == 1, "");
int stackDiff = _assembly.deposit() - m_context.baseStackOffsetOfVariable(*variable) - 1;
if (stackDiff > 16 || stackDiff < 1)
BOOST_THROW_EXCEPTION(
CompilerError() <<
errinfo_sourceLocation(_inlineAssembly.location()) <<
errinfo_comment("Stack too deep, try removing local variables.")
);
for (unsigned i = 0; i < size; ++i)
{
_assembly.append(swapInstruction(stackDiff));
_assembly.append(Instruction::POP);
}
_assembly.append(swapInstruction(stackDiff));
_assembly.append(Instruction::POP);
}
};
codeGen.assemble(