| //= ProgramState.cpp - Path-Sensitive "State" for tracking values --*- C++ -*--= |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements ProgramState and ProgramStateManager. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" |
| #include "clang/Analysis/CFG.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/TaintManager.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace clang; |
| using namespace ento; |
| |
| namespace clang { namespace ento { |
| /// Increments the number of times this state is referenced. |
| |
| void ProgramStateRetain(const ProgramState *state) { |
| ++const_cast<ProgramState*>(state)->refCount; |
| } |
| |
| /// Decrement the number of times this state is referenced. |
| void ProgramStateRelease(const ProgramState *state) { |
| assert(state->refCount > 0); |
| ProgramState *s = const_cast<ProgramState*>(state); |
| if (--s->refCount == 0) { |
| ProgramStateManager &Mgr = s->getStateManager(); |
| Mgr.StateSet.RemoveNode(s); |
| s->~ProgramState(); |
| Mgr.freeStates.push_back(s); |
| } |
| } |
| }} |
| |
| ProgramState::ProgramState(ProgramStateManager *mgr, const Environment& env, |
| StoreRef st, GenericDataMap gdm) |
| : stateMgr(mgr), |
| Env(env), |
| store(st.getStore()), |
| GDM(gdm), |
| refCount(0) { |
| stateMgr->getStoreManager().incrementReferenceCount(store); |
| } |
| |
| ProgramState::ProgramState(const ProgramState &RHS) |
| : llvm::FoldingSetNode(), |
| stateMgr(RHS.stateMgr), |
| Env(RHS.Env), |
| store(RHS.store), |
| GDM(RHS.GDM), |
| refCount(0) { |
| stateMgr->getStoreManager().incrementReferenceCount(store); |
| } |
| |
| ProgramState::~ProgramState() { |
| if (store) |
| stateMgr->getStoreManager().decrementReferenceCount(store); |
| } |
| |
| ProgramStateManager::ProgramStateManager(ASTContext &Ctx, |
| StoreManagerCreator CreateSMgr, |
| ConstraintManagerCreator CreateCMgr, |
| llvm::BumpPtrAllocator &alloc, |
| SubEngine *SubEng) |
| : Eng(SubEng), EnvMgr(alloc), GDMFactory(alloc), |
| svalBuilder(createSimpleSValBuilder(alloc, Ctx, *this)), |
| CallEventMgr(new CallEventManager(alloc)), Alloc(alloc) { |
| StoreMgr.reset((*CreateSMgr)(*this)); |
| ConstraintMgr.reset((*CreateCMgr)(*this, SubEng)); |
| } |
| |
| |
| ProgramStateManager::~ProgramStateManager() { |
| for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end(); |
| I!=E; ++I) |
| I->second.second(I->second.first); |
| } |
| |
| ProgramStateRef |
| ProgramStateManager::removeDeadBindings(ProgramStateRef state, |
| const StackFrameContext *LCtx, |
| SymbolReaper& SymReaper) { |
| |
| // This code essentially performs a "mark-and-sweep" of the VariableBindings. |
| // The roots are any Block-level exprs and Decls that our liveness algorithm |
| // tells us are live. We then see what Decls they may reference, and keep |
| // those around. This code more than likely can be made faster, and the |
| // frequency of which this method is called should be experimented with |
| // for optimum performance. |
| ProgramState NewState = *state; |
| |
| NewState.Env = EnvMgr.removeDeadBindings(NewState.Env, SymReaper, state); |
| |
| // Clean up the store. |
| StoreRef newStore = StoreMgr->removeDeadBindings(NewState.getStore(), LCtx, |
| SymReaper); |
| NewState.setStore(newStore); |
| SymReaper.setReapedStore(newStore); |
| |
| ProgramStateRef Result = getPersistentState(NewState); |
| return ConstraintMgr->removeDeadBindings(Result, SymReaper); |
| } |
| |
| ProgramStateRef ProgramState::bindCompoundLiteral(const CompoundLiteralExpr *CL, |
| const LocationContext *LC, |
| SVal V) const { |
| const StoreRef &newStore = |
| getStateManager().StoreMgr->bindCompoundLiteral(getStore(), CL, LC, V); |
| return makeWithStore(newStore); |
| } |
| |
| ProgramStateRef ProgramState::bindLoc(Loc LV, SVal V, bool notifyChanges) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| ProgramStateRef newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(), |
| LV, V)); |
| const MemRegion *MR = LV.getAsRegion(); |
| if (MR && Mgr.getOwningEngine() && notifyChanges) |
| return Mgr.getOwningEngine()->processRegionChange(newState, MR); |
| |
| return newState; |
| } |
| |
| ProgramStateRef ProgramState::bindDefault(SVal loc, SVal V) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion(); |
| const StoreRef &newStore = Mgr.StoreMgr->BindDefault(getStore(), R, V); |
| ProgramStateRef new_state = makeWithStore(newStore); |
| return Mgr.getOwningEngine() ? |
| Mgr.getOwningEngine()->processRegionChange(new_state, R) : |
| new_state; |
| } |
| |
| ProgramStateRef |
| ProgramState::invalidateRegions(ArrayRef<const MemRegion *> Regions, |
| const Expr *E, unsigned Count, |
| const LocationContext *LCtx, |
| bool CausedByPointerEscape, |
| InvalidatedSymbols *IS, |
| const CallEvent *Call) const { |
| if (!IS) { |
| InvalidatedSymbols invalidated; |
| return invalidateRegionsImpl(Regions, E, Count, LCtx, |
| CausedByPointerEscape, |
| invalidated, Call); |
| } |
| return invalidateRegionsImpl(Regions, E, Count, LCtx, CausedByPointerEscape, |
| *IS, Call); |
| } |
| |
| ProgramStateRef |
| ProgramState::invalidateRegionsImpl(ArrayRef<const MemRegion *> Regions, |
| const Expr *E, unsigned Count, |
| const LocationContext *LCtx, |
| bool CausedByPointerEscape, |
| InvalidatedSymbols &IS, |
| const CallEvent *Call) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| SubEngine* Eng = Mgr.getOwningEngine(); |
| |
| if (Eng) { |
| StoreManager::InvalidatedRegions Invalidated; |
| const StoreRef &newStore |
| = Mgr.StoreMgr->invalidateRegions(getStore(), Regions, E, Count, LCtx, IS, |
| Call, &Invalidated); |
| |
| ProgramStateRef newState = makeWithStore(newStore); |
| |
| if (CausedByPointerEscape) |
| newState = Eng->processPointerEscapedOnInvalidateRegions(newState, |
| &IS, Regions, Invalidated, Call); |
| |
| return Eng->processRegionChanges(newState, &IS, Regions, Invalidated, Call); |
| } |
| |
| const StoreRef &newStore = |
| Mgr.StoreMgr->invalidateRegions(getStore(), Regions, E, Count, LCtx, IS, |
| Call, NULL); |
| return makeWithStore(newStore); |
| } |
| |
| ProgramStateRef ProgramState::killBinding(Loc LV) const { |
| assert(!LV.getAs<loc::MemRegionVal>() && "Use invalidateRegion instead."); |
| |
| Store OldStore = getStore(); |
| const StoreRef &newStore = |
| getStateManager().StoreMgr->killBinding(OldStore, LV); |
| |
| if (newStore.getStore() == OldStore) |
| return this; |
| |
| return makeWithStore(newStore); |
| } |
| |
| ProgramStateRef |
| ProgramState::enterStackFrame(const CallEvent &Call, |
| const StackFrameContext *CalleeCtx) const { |
| const StoreRef &NewStore = |
| getStateManager().StoreMgr->enterStackFrame(getStore(), Call, CalleeCtx); |
| return makeWithStore(NewStore); |
| } |
| |
| SVal ProgramState::getSValAsScalarOrLoc(const MemRegion *R) const { |
| // We only want to do fetches from regions that we can actually bind |
| // values. For example, SymbolicRegions of type 'id<...>' cannot |
| // have direct bindings (but their can be bindings on their subregions). |
| if (!R->isBoundable()) |
| return UnknownVal(); |
| |
| if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) { |
| QualType T = TR->getValueType(); |
| if (Loc::isLocType(T) || T->isIntegerType()) |
| return getSVal(R); |
| } |
| |
| return UnknownVal(); |
| } |
| |
| SVal ProgramState::getSVal(Loc location, QualType T) const { |
| SVal V = getRawSVal(cast<Loc>(location), T); |
| |
| // If 'V' is a symbolic value that is *perfectly* constrained to |
| // be a constant value, use that value instead to lessen the burden |
| // on later analysis stages (so we have less symbolic values to reason |
| // about). |
| if (!T.isNull()) { |
| if (SymbolRef sym = V.getAsSymbol()) { |
| if (const llvm::APSInt *Int = getStateManager() |
| .getConstraintManager() |
| .getSymVal(this, sym)) { |
| // FIXME: Because we don't correctly model (yet) sign-extension |
| // and truncation of symbolic values, we need to convert |
| // the integer value to the correct signedness and bitwidth. |
| // |
| // This shows up in the following: |
| // |
| // char foo(); |
| // unsigned x = foo(); |
| // if (x == 54) |
| // ... |
| // |
| // The symbolic value stored to 'x' is actually the conjured |
| // symbol for the call to foo(); the type of that symbol is 'char', |
| // not unsigned. |
| const llvm::APSInt &NewV = getBasicVals().Convert(T, *Int); |
| |
| if (V.getAs<Loc>()) |
| return loc::ConcreteInt(NewV); |
| else |
| return nonloc::ConcreteInt(NewV); |
| } |
| } |
| } |
| |
| return V; |
| } |
| |
| ProgramStateRef ProgramState::BindExpr(const Stmt *S, |
| const LocationContext *LCtx, |
| SVal V, bool Invalidate) const{ |
| Environment NewEnv = |
| getStateManager().EnvMgr.bindExpr(Env, EnvironmentEntry(S, LCtx), V, |
| Invalidate); |
| if (NewEnv == Env) |
| return this; |
| |
| ProgramState NewSt = *this; |
| NewSt.Env = NewEnv; |
| return getStateManager().getPersistentState(NewSt); |
| } |
| |
| ProgramStateRef ProgramState::assumeInBound(DefinedOrUnknownSVal Idx, |
| DefinedOrUnknownSVal UpperBound, |
| bool Assumption, |
| QualType indexTy) const { |
| if (Idx.isUnknown() || UpperBound.isUnknown()) |
| return this; |
| |
| // Build an expression for 0 <= Idx < UpperBound. |
| // This is the same as Idx + MIN < UpperBound + MIN, if overflow is allowed. |
| // FIXME: This should probably be part of SValBuilder. |
| ProgramStateManager &SM = getStateManager(); |
| SValBuilder &svalBuilder = SM.getSValBuilder(); |
| ASTContext &Ctx = svalBuilder.getContext(); |
| |
| // Get the offset: the minimum value of the array index type. |
| BasicValueFactory &BVF = svalBuilder.getBasicValueFactory(); |
| // FIXME: This should be using ValueManager::ArrayindexTy...somehow. |
| if (indexTy.isNull()) |
| indexTy = Ctx.IntTy; |
| nonloc::ConcreteInt Min(BVF.getMinValue(indexTy)); |
| |
| // Adjust the index. |
| SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add, |
| Idx.castAs<NonLoc>(), Min, indexTy); |
| if (newIdx.isUnknownOrUndef()) |
| return this; |
| |
| // Adjust the upper bound. |
| SVal newBound = |
| svalBuilder.evalBinOpNN(this, BO_Add, UpperBound.castAs<NonLoc>(), |
| Min, indexTy); |
| |
| if (newBound.isUnknownOrUndef()) |
| return this; |
| |
| // Build the actual comparison. |
| SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, newIdx.castAs<NonLoc>(), |
| newBound.castAs<NonLoc>(), Ctx.IntTy); |
| if (inBound.isUnknownOrUndef()) |
| return this; |
| |
| // Finally, let the constraint manager take care of it. |
| ConstraintManager &CM = SM.getConstraintManager(); |
| return CM.assume(this, inBound.castAs<DefinedSVal>(), Assumption); |
| } |
| |
| ConditionTruthVal ProgramState::isNull(SVal V) const { |
| if (V.isZeroConstant()) |
| return true; |
| |
| SymbolRef Sym = V.getAsSymbol(); |
| if (!Sym) |
| return false; |
| return getStateManager().ConstraintMgr->isNull(this, Sym); |
| } |
| |
| ProgramStateRef ProgramStateManager::getInitialState(const LocationContext *InitLoc) { |
| ProgramState State(this, |
| EnvMgr.getInitialEnvironment(), |
| StoreMgr->getInitialStore(InitLoc), |
| GDMFactory.getEmptyMap()); |
| |
| return getPersistentState(State); |
| } |
| |
| ProgramStateRef ProgramStateManager::getPersistentStateWithGDM( |
| ProgramStateRef FromState, |
| ProgramStateRef GDMState) { |
| ProgramState NewState(*FromState); |
| NewState.GDM = GDMState->GDM; |
| return getPersistentState(NewState); |
| } |
| |
| ProgramStateRef ProgramStateManager::getPersistentState(ProgramState &State) { |
| |
| llvm::FoldingSetNodeID ID; |
| State.Profile(ID); |
| void *InsertPos; |
| |
| if (ProgramState *I = StateSet.FindNodeOrInsertPos(ID, InsertPos)) |
| return I; |
| |
| ProgramState *newState = 0; |
| if (!freeStates.empty()) { |
| newState = freeStates.back(); |
| freeStates.pop_back(); |
| } |
| else { |
| newState = (ProgramState*) Alloc.Allocate<ProgramState>(); |
| } |
| new (newState) ProgramState(State); |
| StateSet.InsertNode(newState, InsertPos); |
| return newState; |
| } |
| |
| ProgramStateRef ProgramState::makeWithStore(const StoreRef &store) const { |
| ProgramState NewSt(*this); |
| NewSt.setStore(store); |
| return getStateManager().getPersistentState(NewSt); |
| } |
| |
| void ProgramState::setStore(const StoreRef &newStore) { |
| Store newStoreStore = newStore.getStore(); |
| if (newStoreStore) |
| stateMgr->getStoreManager().incrementReferenceCount(newStoreStore); |
| if (store) |
| stateMgr->getStoreManager().decrementReferenceCount(store); |
| store = newStoreStore; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // State pretty-printing. |
| //===----------------------------------------------------------------------===// |
| |
| void ProgramState::print(raw_ostream &Out, |
| const char *NL, const char *Sep) const { |
| // Print the store. |
| ProgramStateManager &Mgr = getStateManager(); |
| Mgr.getStoreManager().print(getStore(), Out, NL, Sep); |
| |
| // Print out the environment. |
| Env.print(Out, NL, Sep); |
| |
| // Print out the constraints. |
| Mgr.getConstraintManager().print(this, Out, NL, Sep); |
| |
| // Print checker-specific data. |
| Mgr.getOwningEngine()->printState(Out, this, NL, Sep); |
| } |
| |
| void ProgramState::printDOT(raw_ostream &Out) const { |
| print(Out, "\\l", "\\|"); |
| } |
| |
| void ProgramState::dump() const { |
| print(llvm::errs()); |
| } |
| |
| void ProgramState::printTaint(raw_ostream &Out, |
| const char *NL, const char *Sep) const { |
| TaintMapImpl TM = get<TaintMap>(); |
| |
| if (!TM.isEmpty()) |
| Out <<"Tainted Symbols:" << NL; |
| |
| for (TaintMapImpl::iterator I = TM.begin(), E = TM.end(); I != E; ++I) { |
| Out << I->first << " : " << I->second << NL; |
| } |
| } |
| |
| void ProgramState::dumpTaint() const { |
| printTaint(llvm::errs()); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Generic Data Map. |
| //===----------------------------------------------------------------------===// |
| |
| void *const* ProgramState::FindGDM(void *K) const { |
| return GDM.lookup(K); |
| } |
| |
| void* |
| ProgramStateManager::FindGDMContext(void *K, |
| void *(*CreateContext)(llvm::BumpPtrAllocator&), |
| void (*DeleteContext)(void*)) { |
| |
| std::pair<void*, void (*)(void*)>& p = GDMContexts[K]; |
| if (!p.first) { |
| p.first = CreateContext(Alloc); |
| p.second = DeleteContext; |
| } |
| |
| return p.first; |
| } |
| |
| ProgramStateRef ProgramStateManager::addGDM(ProgramStateRef St, void *Key, void *Data){ |
| ProgramState::GenericDataMap M1 = St->getGDM(); |
| ProgramState::GenericDataMap M2 = GDMFactory.add(M1, Key, Data); |
| |
| if (M1 == M2) |
| return St; |
| |
| ProgramState NewSt = *St; |
| NewSt.GDM = M2; |
| return getPersistentState(NewSt); |
| } |
| |
| ProgramStateRef ProgramStateManager::removeGDM(ProgramStateRef state, void *Key) { |
| ProgramState::GenericDataMap OldM = state->getGDM(); |
| ProgramState::GenericDataMap NewM = GDMFactory.remove(OldM, Key); |
| |
| if (NewM == OldM) |
| return state; |
| |
| ProgramState NewState = *state; |
| NewState.GDM = NewM; |
| return getPersistentState(NewState); |
| } |
| |
| bool ScanReachableSymbols::scan(nonloc::CompoundVal val) { |
| for (nonloc::CompoundVal::iterator I=val.begin(), E=val.end(); I!=E; ++I) |
| if (!scan(*I)) |
| return false; |
| |
| return true; |
| } |
| |
| bool ScanReachableSymbols::scan(const SymExpr *sym) { |
| unsigned &isVisited = visited[sym]; |
| if (isVisited) |
| return true; |
| isVisited = 1; |
| |
| if (!visitor.VisitSymbol(sym)) |
| return false; |
| |
| // TODO: should be rewritten using SymExpr::symbol_iterator. |
| switch (sym->getKind()) { |
| case SymExpr::RegionValueKind: |
| case SymExpr::ConjuredKind: |
| case SymExpr::DerivedKind: |
| case SymExpr::ExtentKind: |
| case SymExpr::MetadataKind: |
| break; |
| case SymExpr::CastSymbolKind: |
| return scan(cast<SymbolCast>(sym)->getOperand()); |
| case SymExpr::SymIntKind: |
| return scan(cast<SymIntExpr>(sym)->getLHS()); |
| case SymExpr::IntSymKind: |
| return scan(cast<IntSymExpr>(sym)->getRHS()); |
| case SymExpr::SymSymKind: { |
| const SymSymExpr *x = cast<SymSymExpr>(sym); |
| return scan(x->getLHS()) && scan(x->getRHS()); |
| } |
| } |
| return true; |
| } |
| |
| bool ScanReachableSymbols::scan(SVal val) { |
| if (Optional<loc::MemRegionVal> X = val.getAs<loc::MemRegionVal>()) |
| return scan(X->getRegion()); |
| |
| if (Optional<nonloc::LazyCompoundVal> X = |
| val.getAs<nonloc::LazyCompoundVal>()) { |
| StoreManager &StoreMgr = state->getStateManager().getStoreManager(); |
| // FIXME: We don't really want to use getBaseRegion() here because pointer |
| // arithmetic doesn't apply, but scanReachableSymbols only accepts base |
| // regions right now. |
| if (!StoreMgr.scanReachableSymbols(X->getStore(), |
| X->getRegion()->getBaseRegion(), |
| *this)) |
| return false; |
| } |
| |
| if (Optional<nonloc::LocAsInteger> X = val.getAs<nonloc::LocAsInteger>()) |
| return scan(X->getLoc()); |
| |
| if (SymbolRef Sym = val.getAsSymbol()) |
| return scan(Sym); |
| |
| if (const SymExpr *Sym = val.getAsSymbolicExpression()) |
| return scan(Sym); |
| |
| if (Optional<nonloc::CompoundVal> X = val.getAs<nonloc::CompoundVal>()) |
| return scan(*X); |
| |
| return true; |
| } |
| |
| bool ScanReachableSymbols::scan(const MemRegion *R) { |
| if (isa<MemSpaceRegion>(R)) |
| return true; |
| |
| unsigned &isVisited = visited[R]; |
| if (isVisited) |
| return true; |
| isVisited = 1; |
| |
| |
| if (!visitor.VisitMemRegion(R)) |
| return false; |
| |
| // If this is a symbolic region, visit the symbol for the region. |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) |
| if (!visitor.VisitSymbol(SR->getSymbol())) |
| return false; |
| |
| // If this is a subregion, also visit the parent regions. |
| if (const SubRegion *SR = dyn_cast<SubRegion>(R)) { |
| const MemRegion *Super = SR->getSuperRegion(); |
| if (!scan(Super)) |
| return false; |
| |
| // When we reach the topmost region, scan all symbols in it. |
| if (isa<MemSpaceRegion>(Super)) { |
| StoreManager &StoreMgr = state->getStateManager().getStoreManager(); |
| if (!StoreMgr.scanReachableSymbols(state->getStore(), SR, *this)) |
| return false; |
| } |
| } |
| |
| // Regions captured by a block are also implicitly reachable. |
| if (const BlockDataRegion *BDR = dyn_cast<BlockDataRegion>(R)) { |
| BlockDataRegion::referenced_vars_iterator I = BDR->referenced_vars_begin(), |
| E = BDR->referenced_vars_end(); |
| for ( ; I != E; ++I) { |
| if (!scan(I.getCapturedRegion())) |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool ProgramState::scanReachableSymbols(SVal val, SymbolVisitor& visitor) const { |
| ScanReachableSymbols S(this, visitor); |
| return S.scan(val); |
| } |
| |
| bool ProgramState::scanReachableSymbols(const SVal *I, const SVal *E, |
| SymbolVisitor &visitor) const { |
| ScanReachableSymbols S(this, visitor); |
| for ( ; I != E; ++I) { |
| if (!S.scan(*I)) |
| return false; |
| } |
| return true; |
| } |
| |
| bool ProgramState::scanReachableSymbols(const MemRegion * const *I, |
| const MemRegion * const *E, |
| SymbolVisitor &visitor) const { |
| ScanReachableSymbols S(this, visitor); |
| for ( ; I != E; ++I) { |
| if (!S.scan(*I)) |
| return false; |
| } |
| return true; |
| } |
| |
| ProgramStateRef ProgramState::addTaint(const Stmt *S, |
| const LocationContext *LCtx, |
| TaintTagType Kind) const { |
| if (const Expr *E = dyn_cast_or_null<Expr>(S)) |
| S = E->IgnoreParens(); |
| |
| SymbolRef Sym = getSVal(S, LCtx).getAsSymbol(); |
| if (Sym) |
| return addTaint(Sym, Kind); |
| |
| const MemRegion *R = getSVal(S, LCtx).getAsRegion(); |
| addTaint(R, Kind); |
| |
| // Cannot add taint, so just return the state. |
| return this; |
| } |
| |
| ProgramStateRef ProgramState::addTaint(const MemRegion *R, |
| TaintTagType Kind) const { |
| if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R)) |
| return addTaint(SR->getSymbol(), Kind); |
| return this; |
| } |
| |
| ProgramStateRef ProgramState::addTaint(SymbolRef Sym, |
| TaintTagType Kind) const { |
| // If this is a symbol cast, remove the cast before adding the taint. Taint |
| // is cast agnostic. |
| while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym)) |
| Sym = SC->getOperand(); |
| |
| ProgramStateRef NewState = set<TaintMap>(Sym, Kind); |
| assert(NewState); |
| return NewState; |
| } |
| |
| bool ProgramState::isTainted(const Stmt *S, const LocationContext *LCtx, |
| TaintTagType Kind) const { |
| if (const Expr *E = dyn_cast_or_null<Expr>(S)) |
| S = E->IgnoreParens(); |
| |
| SVal val = getSVal(S, LCtx); |
| return isTainted(val, Kind); |
| } |
| |
| bool ProgramState::isTainted(SVal V, TaintTagType Kind) const { |
| if (const SymExpr *Sym = V.getAsSymExpr()) |
| return isTainted(Sym, Kind); |
| if (const MemRegion *Reg = V.getAsRegion()) |
| return isTainted(Reg, Kind); |
| return false; |
| } |
| |
| bool ProgramState::isTainted(const MemRegion *Reg, TaintTagType K) const { |
| if (!Reg) |
| return false; |
| |
| // Element region (array element) is tainted if either the base or the offset |
| // are tainted. |
| if (const ElementRegion *ER = dyn_cast<ElementRegion>(Reg)) |
| return isTainted(ER->getSuperRegion(), K) || isTainted(ER->getIndex(), K); |
| |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(Reg)) |
| return isTainted(SR->getSymbol(), K); |
| |
| if (const SubRegion *ER = dyn_cast<SubRegion>(Reg)) |
| return isTainted(ER->getSuperRegion(), K); |
| |
| return false; |
| } |
| |
| bool ProgramState::isTainted(SymbolRef Sym, TaintTagType Kind) const { |
| if (!Sym) |
| return false; |
| |
| // Traverse all the symbols this symbol depends on to see if any are tainted. |
| bool Tainted = false; |
| for (SymExpr::symbol_iterator SI = Sym->symbol_begin(), SE =Sym->symbol_end(); |
| SI != SE; ++SI) { |
| if (!isa<SymbolData>(*SI)) |
| continue; |
| |
| const TaintTagType *Tag = get<TaintMap>(*SI); |
| Tainted = (Tag && *Tag == Kind); |
| |
| // If this is a SymbolDerived with a tainted parent, it's also tainted. |
| if (const SymbolDerived *SD = dyn_cast<SymbolDerived>(*SI)) |
| Tainted = Tainted || isTainted(SD->getParentSymbol(), Kind); |
| |
| // If memory region is tainted, data is also tainted. |
| if (const SymbolRegionValue *SRV = dyn_cast<SymbolRegionValue>(*SI)) |
| Tainted = Tainted || isTainted(SRV->getRegion(), Kind); |
| |
| // If If this is a SymbolCast from a tainted value, it's also tainted. |
| if (const SymbolCast *SC = dyn_cast<SymbolCast>(*SI)) |
| Tainted = Tainted || isTainted(SC->getOperand(), Kind); |
| |
| if (Tainted) |
| return true; |
| } |
| |
| return Tainted; |
| } |
| |
| /// The GDM component containing the dynamic type info. This is a map from a |
| /// symbol to its most likely type. |
| REGISTER_TRAIT_WITH_PROGRAMSTATE(DynamicTypeMap, |
| CLANG_ENTO_PROGRAMSTATE_MAP(const MemRegion *, |
| DynamicTypeInfo)) |
| |
| DynamicTypeInfo ProgramState::getDynamicTypeInfo(const MemRegion *Reg) const { |
| Reg = Reg->StripCasts(); |
| |
| // Look up the dynamic type in the GDM. |
| const DynamicTypeInfo *GDMType = get<DynamicTypeMap>(Reg); |
| if (GDMType) |
| return *GDMType; |
| |
| // Otherwise, fall back to what we know about the region. |
| if (const TypedRegion *TR = dyn_cast<TypedRegion>(Reg)) |
| return DynamicTypeInfo(TR->getLocationType(), /*CanBeSubclass=*/false); |
| |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(Reg)) { |
| SymbolRef Sym = SR->getSymbol(); |
| return DynamicTypeInfo(Sym->getType()); |
| } |
| |
| return DynamicTypeInfo(); |
| } |
| |
| ProgramStateRef ProgramState::setDynamicTypeInfo(const MemRegion *Reg, |
| DynamicTypeInfo NewTy) const { |
| Reg = Reg->StripCasts(); |
| ProgramStateRef NewState = set<DynamicTypeMap>(Reg, NewTy); |
| assert(NewState); |
| return NewState; |
| } |
