| //= 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/Analysis/CFG.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.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; |
| |
| // Give the vtable for ConstraintManager somewhere to live. |
| // FIXME: Move this elsewhere. |
| ConstraintManager::~ConstraintManager() {} |
| |
| 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() { |
| for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end(); |
| I!=E; ++I) |
| I->second.second(I->second.first); |
| } |
| |
| const ProgramState* |
| ProgramStateManager::removeDeadBindings(const ProgramState *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); |
| |
| return getPersistentState(NewState); |
| } |
| |
| const ProgramState *ProgramStateManager::MarshalState(const ProgramState *state, |
| const StackFrameContext *InitLoc) { |
| // make up an empty state for now. |
| ProgramState State(this, |
| EnvMgr.getInitialEnvironment(), |
| StoreMgr->getInitialStore(InitLoc), |
| GDMFactory.getEmptyMap()); |
| |
| return getPersistentState(State); |
| } |
| |
| const ProgramState *ProgramState::bindCompoundLiteral(const CompoundLiteralExpr *CL, |
| const LocationContext *LC, |
| SVal V) const { |
| const StoreRef &newStore = |
| getStateManager().StoreMgr->BindCompoundLiteral(getStore(), CL, LC, V); |
| return makeWithStore(newStore); |
| } |
| |
| const ProgramState *ProgramState::bindDecl(const VarRegion* VR, SVal IVal) const { |
| const StoreRef &newStore = |
| getStateManager().StoreMgr->BindDecl(getStore(), VR, IVal); |
| return makeWithStore(newStore); |
| } |
| |
| const ProgramState *ProgramState::bindDeclWithNoInit(const VarRegion* VR) const { |
| const StoreRef &newStore = |
| getStateManager().StoreMgr->BindDeclWithNoInit(getStore(), VR); |
| return makeWithStore(newStore); |
| } |
| |
| const ProgramState *ProgramState::bindLoc(Loc LV, SVal V) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| const ProgramState *newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(), |
| LV, V)); |
| const MemRegion *MR = LV.getAsRegion(); |
| if (MR && Mgr.getOwningEngine()) |
| return Mgr.getOwningEngine()->processRegionChange(newState, MR); |
| |
| return newState; |
| } |
| |
| const ProgramState *ProgramState::bindDefault(SVal loc, SVal V) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| const MemRegion *R = cast<loc::MemRegionVal>(loc).getRegion(); |
| const StoreRef &newStore = Mgr.StoreMgr->BindDefault(getStore(), R, V); |
| const ProgramState *new_state = makeWithStore(newStore); |
| return Mgr.getOwningEngine() ? |
| Mgr.getOwningEngine()->processRegionChange(new_state, R) : |
| new_state; |
| } |
| |
| const ProgramState * |
| ProgramState::invalidateRegions(ArrayRef<const MemRegion *> Regions, |
| const Expr *E, unsigned Count, |
| StoreManager::InvalidatedSymbols *IS, |
| const CallOrObjCMessage *Call) const { |
| if (!IS) { |
| StoreManager::InvalidatedSymbols invalidated; |
| return invalidateRegionsImpl(Regions, E, Count, |
| invalidated, Call); |
| } |
| return invalidateRegionsImpl(Regions, E, Count, *IS, Call); |
| } |
| |
| const ProgramState * |
| ProgramState::invalidateRegionsImpl(ArrayRef<const MemRegion *> Regions, |
| const Expr *E, unsigned Count, |
| StoreManager::InvalidatedSymbols &IS, |
| const CallOrObjCMessage *Call) const { |
| ProgramStateManager &Mgr = getStateManager(); |
| SubEngine* Eng = Mgr.getOwningEngine(); |
| |
| if (Eng && Eng->wantsRegionChangeUpdate(this)) { |
| StoreManager::InvalidatedRegions Invalidated; |
| const StoreRef &newStore |
| = Mgr.StoreMgr->invalidateRegions(getStore(), Regions, E, Count, IS, |
| Call, &Invalidated); |
| const ProgramState *newState = makeWithStore(newStore); |
| return Eng->processRegionChanges(newState, &IS, Regions, Invalidated); |
| } |
| |
| const StoreRef &newStore = |
| Mgr.StoreMgr->invalidateRegions(getStore(), Regions, E, Count, IS, |
| Call, NULL); |
| return makeWithStore(newStore); |
| } |
| |
| const ProgramState *ProgramState::unbindLoc(Loc LV) const { |
| assert(!isa<loc::MemRegionVal>(LV) && "Use invalidateRegion instead."); |
| |
| Store OldStore = getStore(); |
| const StoreRef &newStore = getStateManager().StoreMgr->Remove(OldStore, LV); |
| |
| if (newStore.getStore() == OldStore) |
| return this; |
| |
| return makeWithStore(newStore); |
| } |
| |
| const ProgramState *ProgramState::enterStackFrame(const StackFrameContext *frame) const { |
| const StoreRef &new_store = |
| getStateManager().StoreMgr->enterStackFrame(this, frame); |
| return makeWithStore(new_store); |
| } |
| |
| 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 = getSymVal(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 (isa<Loc>(V)) |
| return loc::ConcreteInt(NewV); |
| else |
| return nonloc::ConcreteInt(NewV); |
| } |
| } |
| } |
| |
| return V; |
| } |
| |
| const ProgramState *ProgramState::BindExpr(const Stmt *S, SVal V, bool Invalidate) const{ |
| Environment NewEnv = getStateManager().EnvMgr.bindExpr(Env, S, V, |
| Invalidate); |
| if (NewEnv == Env) |
| return this; |
| |
| ProgramState NewSt = *this; |
| NewSt.Env = NewEnv; |
| return getStateManager().getPersistentState(NewSt); |
| } |
| |
| const ProgramState *ProgramState::bindExprAndLocation(const Stmt *S, SVal location, |
| SVal V) const { |
| Environment NewEnv = |
| getStateManager().EnvMgr.bindExprAndLocation(Env, S, location, V); |
| |
| if (NewEnv == Env) |
| return this; |
| |
| ProgramState NewSt = *this; |
| NewSt.Env = NewEnv; |
| return getStateManager().getPersistentState(NewSt); |
| } |
| |
| const ProgramState *ProgramState::assumeInBound(DefinedOrUnknownSVal Idx, |
| DefinedOrUnknownSVal UpperBound, |
| bool Assumption) 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. |
| QualType indexTy = Ctx.IntTy; |
| nonloc::ConcreteInt Min(BVF.getMinValue(indexTy)); |
| |
| // Adjust the index. |
| SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add, |
| cast<NonLoc>(Idx), Min, indexTy); |
| if (newIdx.isUnknownOrUndef()) |
| return this; |
| |
| // Adjust the upper bound. |
| SVal newBound = |
| svalBuilder.evalBinOpNN(this, BO_Add, cast<NonLoc>(UpperBound), |
| Min, indexTy); |
| |
| if (newBound.isUnknownOrUndef()) |
| return this; |
| |
| // Build the actual comparison. |
| SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, |
| cast<NonLoc>(newIdx), cast<NonLoc>(newBound), |
| Ctx.IntTy); |
| if (inBound.isUnknownOrUndef()) |
| return this; |
| |
| // Finally, let the constraint manager take care of it. |
| ConstraintManager &CM = SM.getConstraintManager(); |
| return CM.assume(this, cast<DefinedSVal>(inBound), Assumption); |
| } |
| |
| const ProgramState *ProgramStateManager::getInitialState(const LocationContext *InitLoc) { |
| ProgramState State(this, |
| EnvMgr.getInitialEnvironment(), |
| StoreMgr->getInitialStore(InitLoc), |
| GDMFactory.getEmptyMap()); |
| |
| return getPersistentState(State); |
| } |
| |
| void ProgramStateManager::recycleUnusedStates() { |
| for (std::vector<ProgramState*>::iterator i = recentlyAllocatedStates.begin(), |
| e = recentlyAllocatedStates.end(); i != e; ++i) { |
| ProgramState *state = *i; |
| if (state->referencedByExplodedNode()) |
| continue; |
| StateSet.RemoveNode(state); |
| freeStates.push_back(state); |
| state->~ProgramState(); |
| } |
| recentlyAllocatedStates.clear(); |
| } |
| |
| const ProgramState *ProgramStateManager::getPersistentStateWithGDM( |
| const ProgramState *FromState, |
| const ProgramState *GDMState) { |
| ProgramState NewState = *FromState; |
| NewState.GDM = GDMState->GDM; |
| return getPersistentState(NewState); |
| } |
| |
| const ProgramState *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); |
| recentlyAllocatedStates.push_back(newState); |
| return newState; |
| } |
| |
| const ProgramState *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. |
| //===----------------------------------------------------------------------===// |
| |
| static bool IsEnvLoc(const Stmt *S) { |
| // FIXME: This is a layering violation. Should be in environment. |
| return (bool) (((uintptr_t) S) & 0x1); |
| } |
| |
| void ProgramState::print(raw_ostream &Out, CFG *C, |
| const char *NL, const char *Sep) const { |
| // Print the store. |
| ProgramStateManager &Mgr = getStateManager(); |
| Mgr.getStoreManager().print(getStore(), Out, NL, Sep); |
| bool isFirst = true; |
| |
| // FIXME: All environment printing should be moved inside Environment. |
| if (C) { |
| // Print Subexpression bindings. |
| for (Environment::iterator I = Env.begin(), E = Env.end(); I != E; ++I) { |
| if (C->isBlkExpr(I.getKey()) || IsEnvLoc(I.getKey())) |
| continue; |
| |
| if (isFirst) { |
| Out << NL << NL << "Sub-Expressions:" << NL; |
| isFirst = false; |
| } else { |
| Out << NL; |
| } |
| |
| Out << " (" << (void*) I.getKey() << ") "; |
| LangOptions LO; // FIXME. |
| I.getKey()->printPretty(Out, 0, PrintingPolicy(LO)); |
| Out << " : " << I.getData(); |
| } |
| |
| // Print block-expression bindings. |
| isFirst = true; |
| for (Environment::iterator I = Env.begin(), E = Env.end(); I != E; ++I) { |
| if (!C->isBlkExpr(I.getKey())) |
| continue; |
| |
| if (isFirst) { |
| Out << NL << NL << "Block-level Expressions:" << NL; |
| isFirst = false; |
| } else { |
| Out << NL; |
| } |
| |
| Out << " (" << (void*) I.getKey() << ") "; |
| LangOptions LO; // FIXME. |
| I.getKey()->printPretty(Out, 0, PrintingPolicy(LO)); |
| Out << " : " << I.getData(); |
| } |
| } else { |
| // Print All bindings - no info to differentiate block from subexpressions. |
| for (Environment::iterator I = Env.begin(), E = Env.end(); I != E; ++I) { |
| if (IsEnvLoc(I.getKey())) |
| continue; |
| |
| if (isFirst) { |
| Out << NL << NL << "Expressions:" << NL; |
| isFirst = false; |
| } else { |
| Out << NL; |
| } |
| |
| Out << " (" << (void*) I.getKey() << ") "; |
| LangOptions LO; // FIXME. |
| I.getKey()->printPretty(Out, 0, PrintingPolicy(LO)); |
| Out << " : " << I.getData(); |
| } |
| } |
| |
| // Print locations. |
| isFirst = true; |
| |
| for (Environment::iterator I = Env.begin(), E = Env.end(); I != E; ++I) { |
| if (!IsEnvLoc(I.getKey())) |
| continue; |
| |
| if (isFirst) { |
| Out << NL << NL << "Load/store locations:" << NL; |
| isFirst = false; |
| } else { |
| Out << NL; |
| } |
| |
| const Stmt *S = (Stmt*) (((uintptr_t) I.getKey()) & ((uintptr_t) ~0x1)); |
| |
| Out << " (" << (void*) S << ") "; |
| LangOptions LO; // FIXME. |
| S->printPretty(Out, 0, PrintingPolicy(LO)); |
| Out << " : " << I.getData(); |
| } |
| |
| Mgr.getConstraintManager().print(this, Out, NL, Sep); |
| |
| // Print checker-specific data. |
| Mgr.getOwningEngine()->printState(Out, this, NL, Sep); |
| } |
| |
| void ProgramState::printDOT(raw_ostream &Out, CFG &C) const { |
| print(Out, &C, "\\l", "\\|"); |
| } |
| |
| void ProgramState::dump(CFG &C) const { |
| print(llvm::errs(), &C); |
| } |
| |
| void ProgramState::dump() const { |
| print(llvm::errs(), 0); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // 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; |
| } |
| |
| const ProgramState *ProgramStateManager::addGDM(const ProgramState *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); |
| } |
| |
| const ProgramState *ProgramStateManager::removeGDM(const ProgramState *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); |
| } |
| |
| void ScanReachableSymbols::anchor() { } |
| |
| 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 (loc::MemRegionVal *X = dyn_cast<loc::MemRegionVal>(&val)) |
| return scan(X->getRegion()); |
| |
| if (nonloc::LocAsInteger *X = dyn_cast<nonloc::LocAsInteger>(&val)) |
| return scan(X->getLoc()); |
| |
| if (SymbolRef Sym = val.getAsSymbol()) |
| return scan(Sym); |
| |
| if (const SymExpr *Sym = val.getAsSymbolicExpression()) |
| return scan(Sym); |
| |
| if (nonloc::CompoundVal *X = dyn_cast<nonloc::CompoundVal>(&val)) |
| 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 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)) |
| if (!scan(SR->getSuperRegion())) |
| return false; |
| |
| // Now look at the binding to this region (if any). |
| if (!scan(state->getSValAsScalarOrLoc(R))) |
| return false; |
| |
| // Now look at the subregions. |
| if (!SRM.get()) |
| SRM.reset(state->getStateManager().getStoreManager(). |
| getSubRegionMap(state->getStore())); |
| |
| return SRM->iterSubRegions(R, *this); |
| } |
| |
| 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; |
| } |
| |
| const ProgramState* ProgramState::addTaint(const Stmt *S, |
| TaintTagType Kind) const { |
| if (const Expr *E = dyn_cast_or_null<Expr>(S)) |
| S = E->IgnoreParens(); |
| |
| SymbolRef Sym = getSVal(S).getAsSymbol(); |
| if (Sym) |
| return addTaint(Sym, Kind); |
| |
| const MemRegion *R = getSVal(S).getAsRegion(); |
| addTaint(R, Kind); |
| |
| // Cannot add taint, so just return the state. |
| return this; |
| } |
| |
| const ProgramState* 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; |
| } |
| |
| const ProgramState* ProgramState::addTaint(SymbolRef Sym, |
| TaintTagType Kind) const { |
| const ProgramState *NewState = set<TaintMap>(Sym, Kind); |
| assert(NewState); |
| return NewState; |
| } |
| |
| bool ProgramState::isTainted(const Stmt *S, TaintTagType Kind) const { |
| if (const Expr *E = dyn_cast_or_null<Expr>(S)) |
| S = E->IgnoreParens(); |
| |
| SVal val = getSVal(S); |
| 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(const SymExpr* 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) { |
| assert(isa<SymbolData>(*SI)); |
| 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 (Tainted) |
| return true; |
| } |
| |
| return Tainted; |
| } |