| //=== 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 "ExprEngineInternalChecks.h" |
| #include "clang/GR/BugReporter/BugType.h" |
| #include "clang/GR/PathSensitive/CheckerVisitor.h" |
| |
| using namespace clang; |
| using namespace ento; |
| |
| namespace { |
| class 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() != BO_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()) { |
| 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 ento::RegisterFixedAddressChecker(ExprEngine &Eng) { |
| Eng.registerCheck(new FixedAddressChecker()); |
| } |