llvm-project/clang/lib/Analysis/FixedAddressChecker.cpp

71 lines
2.1 KiB
C++

//=== FixedAddressChecker.cpp - Fixed address usage checker ----*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This files defines FixedAddressChecker, a builtin checker that checks for
// assignment of a fixed address to a pointer.
// This check corresponds to CWE-587.
//
//===----------------------------------------------------------------------===//
#include "clang/Analysis/PathSensitive/CheckerVisitor.h"
#include "GRExprEngineInternalChecks.h"
using namespace clang;
namespace {
class VISIBILITY_HIDDEN FixedAddressChecker
: public CheckerVisitor<FixedAddressChecker> {
BuiltinBug *BT;
public:
FixedAddressChecker() : BT(0) {}
static void *getTag();
void PreVisitBinaryOperator(CheckerContext &C, const BinaryOperator *B);
};
}
void *FixedAddressChecker::getTag() {
static int x;
return &x;
}
void FixedAddressChecker::PreVisitBinaryOperator(CheckerContext &C,
const BinaryOperator *B) {
// Using a fixed address is not portable because that address will probably
// not be valid in all environments or platforms.
if (B->getOpcode() != BinaryOperator::Assign)
return;
QualType T = B->getType();
if (!T->isPointerType())
return;
const GRState *state = C.getState();
SVal RV = state->getSVal(B->getRHS());
if (!RV.isConstant() || RV.isZeroConstant())
return;
if (ExplodedNode *N = C.GenerateNode(B)) {
if (!BT)
BT = new BuiltinBug("Use fixed address",
"Using a fixed address is not portable because that "
"address will probably not be valid in all "
"environments or platforms.");
RangedBugReport *R = new RangedBugReport(*BT, BT->getDescription(), N);
R->addRange(B->getRHS()->getSourceRange());
C.EmitReport(R);
}
}
void clang::RegisterFixedAddressChecker(GRExprEngine &Eng) {
Eng.registerCheck(new FixedAddressChecker());
}