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diff --git a/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
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+//==--- MacOSKeychainAPIChecker.cpp ------------------------------*- C++ -*-==//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// This checker flags misuses of KeyChainAPI. In particular, the password data
+// allocated/returned by SecKeychainItemCopyContent,
+// SecKeychainFindGenericPassword, SecKeychainFindInternetPassword functions has
+// to be freed using a call to SecKeychainItemFreeContent.
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
+#include "llvm/ADT/SmallString.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class MacOSKeychainAPIChecker : public Checker<check::PreStmt<CallExpr>,
+ check::PreStmt<ReturnStmt>,
+ check::PostStmt<CallExpr>,
+ check::EndPath,
+ check::DeadSymbols> {
+ mutable OwningPtr<BugType> BT;
+
+public:
+ /// AllocationState is a part of the checker specific state together with the
+ /// MemRegion corresponding to the allocated data.
+ struct AllocationState {
+ /// The index of the allocator function.
+ unsigned int AllocatorIdx;
+ SymbolRef Region;
+
+ AllocationState(const Expr *E, unsigned int Idx, SymbolRef R) :
+ AllocatorIdx(Idx),
+ Region(R) {}
+
+ bool operator==(const AllocationState &X) const {
+ return (AllocatorIdx == X.AllocatorIdx &&
+ Region == X.Region);
+ }
+
+ void Profile(llvm::FoldingSetNodeID &ID) const {
+ ID.AddInteger(AllocatorIdx);
+ ID.AddPointer(Region);
+ }
+ };
+
+ void checkPreStmt(const CallExpr *S, CheckerContext &C) const;
+ void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const;
+ void checkPostStmt(const CallExpr *S, CheckerContext &C) const;
+ void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const;
+ void checkEndPath(CheckerContext &C) const;
+
+private:
+ typedef std::pair<SymbolRef, const AllocationState*> AllocationPair;
+ typedef llvm::SmallVector<AllocationPair, 2> AllocationPairVec;
+
+ enum APIKind {
+ /// Denotes functions tracked by this checker.
+ ValidAPI = 0,
+ /// The functions commonly/mistakenly used in place of the given API.
+ ErrorAPI = 1,
+ /// The functions which may allocate the data. These are tracked to reduce
+ /// the false alarm rate.
+ PossibleAPI = 2
+ };
+ /// Stores the information about the allocator and deallocator functions -
+ /// these are the functions the checker is tracking.
+ struct ADFunctionInfo {
+ const char* Name;
+ unsigned int Param;
+ unsigned int DeallocatorIdx;
+ APIKind Kind;
+ };
+ static const unsigned InvalidIdx = 100000;
+ static const unsigned FunctionsToTrackSize = 8;
+ static const ADFunctionInfo FunctionsToTrack[FunctionsToTrackSize];
+ /// The value, which represents no error return value for allocator functions.
+ static const unsigned NoErr = 0;
+
+ /// Given the function name, returns the index of the allocator/deallocator
+ /// function.
+ static unsigned getTrackedFunctionIndex(StringRef Name, bool IsAllocator);
+
+ inline void initBugType() const {
+ if (!BT)
+ BT.reset(new BugType("Improper use of SecKeychain API", "Mac OS API"));
+ }
+
+ void generateDeallocatorMismatchReport(const AllocationPair &AP,
+ const Expr *ArgExpr,
+ CheckerContext &C) const;
+
+ /// Find the allocation site for Sym on the path leading to the node N.
+ const Stmt *getAllocationSite(const ExplodedNode *N, SymbolRef Sym,
+ CheckerContext &C) const;
+
+ BugReport *generateAllocatedDataNotReleasedReport(const AllocationPair &AP,
+ ExplodedNode *N,
+ CheckerContext &C) const;
+
+ /// Check if RetSym evaluates to an error value in the current state.
+ bool definitelyReturnedError(SymbolRef RetSym,
+ ProgramStateRef State,
+ SValBuilder &Builder,
+ bool noError = false) const;
+
+ /// Check if RetSym evaluates to a NoErr value in the current state.
+ bool definitelyDidnotReturnError(SymbolRef RetSym,
+ ProgramStateRef State,
+ SValBuilder &Builder) const {
+ return definitelyReturnedError(RetSym, State, Builder, true);
+ }
+
+ /// Mark an AllocationPair interesting for diagnostic reporting.
+ void markInteresting(BugReport *R, const AllocationPair &AP) const {
+ R->markInteresting(AP.first);
+ R->markInteresting(AP.second->Region);
+ }
+
+ /// The bug visitor which allows us to print extra diagnostics along the
+ /// BugReport path. For example, showing the allocation site of the leaked
+ /// region.
+ class SecKeychainBugVisitor
+ : public BugReporterVisitorImpl<SecKeychainBugVisitor> {
+ protected:
+ // The allocated region symbol tracked by the main analysis.
+ SymbolRef Sym;
+
+ public:
+ SecKeychainBugVisitor(SymbolRef S) : Sym(S) {}
+ virtual ~SecKeychainBugVisitor() {}
+
+ void Profile(llvm::FoldingSetNodeID &ID) const {
+ static int X = 0;
+ ID.AddPointer(&X);
+ ID.AddPointer(Sym);
+ }
+
+ PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
+ const ExplodedNode *PrevN,
+ BugReporterContext &BRC,
+ BugReport &BR);
+ };
+};
+}
+
+/// ProgramState traits to store the currently allocated (and not yet freed)
+/// symbols. This is a map from the allocated content symbol to the
+/// corresponding AllocationState.
+typedef llvm::ImmutableMap<SymbolRef,
+ MacOSKeychainAPIChecker::AllocationState> AllocatedSetTy;
+
+namespace { struct AllocatedData {}; }
+namespace clang { namespace ento {
+template<> struct ProgramStateTrait<AllocatedData>
+ : public ProgramStatePartialTrait<AllocatedSetTy > {
+ static void *GDMIndex() { static int index = 0; return &index; }
+};
+}}
+
+static bool isEnclosingFunctionParam(const Expr *E) {
+ E = E->IgnoreParenCasts();
+ if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
+ const ValueDecl *VD = DRE->getDecl();
+ if (isa<ImplicitParamDecl>(VD) || isa<ParmVarDecl>(VD))
+ return true;
+ }
+ return false;
+}
+
+const MacOSKeychainAPIChecker::ADFunctionInfo
+ MacOSKeychainAPIChecker::FunctionsToTrack[FunctionsToTrackSize] = {
+ {"SecKeychainItemCopyContent", 4, 3, ValidAPI}, // 0
+ {"SecKeychainFindGenericPassword", 6, 3, ValidAPI}, // 1
+ {"SecKeychainFindInternetPassword", 13, 3, ValidAPI}, // 2
+ {"SecKeychainItemFreeContent", 1, InvalidIdx, ValidAPI}, // 3
+ {"SecKeychainItemCopyAttributesAndData", 5, 5, ValidAPI}, // 4
+ {"SecKeychainItemFreeAttributesAndData", 1, InvalidIdx, ValidAPI}, // 5
+ {"free", 0, InvalidIdx, ErrorAPI}, // 6
+ {"CFStringCreateWithBytesNoCopy", 1, InvalidIdx, PossibleAPI}, // 7
+};
+
+unsigned MacOSKeychainAPIChecker::getTrackedFunctionIndex(StringRef Name,
+ bool IsAllocator) {
+ for (unsigned I = 0; I < FunctionsToTrackSize; ++I) {
+ ADFunctionInfo FI = FunctionsToTrack[I];
+ if (FI.Name != Name)
+ continue;
+ // Make sure the function is of the right type (allocator vs deallocator).
+ if (IsAllocator && (FI.DeallocatorIdx == InvalidIdx))
+ return InvalidIdx;
+ if (!IsAllocator && (FI.DeallocatorIdx != InvalidIdx))
+ return InvalidIdx;
+
+ return I;
+ }
+ // The function is not tracked.
+ return InvalidIdx;
+}
+
+static bool isBadDeallocationArgument(const MemRegion *Arg) {
+ if (!Arg)
+ return false;
+ if (isa<AllocaRegion>(Arg) ||
+ isa<BlockDataRegion>(Arg) ||
+ isa<TypedRegion>(Arg)) {
+ return true;
+ }
+ return false;
+}
+
+/// Given the address expression, retrieve the value it's pointing to. Assume
+/// that value is itself an address, and return the corresponding symbol.
+static SymbolRef getAsPointeeSymbol(const Expr *Expr,
+ CheckerContext &C) {
+ ProgramStateRef State = C.getState();
+ SVal ArgV = State->getSVal(Expr, C.getLocationContext());
+
+ if (const loc::MemRegionVal *X = dyn_cast<loc::MemRegionVal>(&ArgV)) {
+ StoreManager& SM = C.getStoreManager();
+ SymbolRef sym = SM.getBinding(State->getStore(), *X).getAsLocSymbol();
+ if (sym)
+ return sym;
+ }
+ return 0;
+}
+
+// When checking for error code, we need to consider the following cases:
+// 1) noErr / [0]
+// 2) someErr / [1, inf]
+// 3) unknown
+// If noError, returns true iff (1).
+// If !noError, returns true iff (2).
+bool MacOSKeychainAPIChecker::definitelyReturnedError(SymbolRef RetSym,
+ ProgramStateRef State,
+ SValBuilder &Builder,
+ bool noError) const {
+ DefinedOrUnknownSVal NoErrVal = Builder.makeIntVal(NoErr,
+ Builder.getSymbolManager().getType(RetSym));
+ DefinedOrUnknownSVal NoErr = Builder.evalEQ(State, NoErrVal,
+ nonloc::SymbolVal(RetSym));
+ ProgramStateRef ErrState = State->assume(NoErr, noError);
+ if (ErrState == State) {
+ return true;
+ }
+
+ return false;
+}
+
+// Report deallocator mismatch. Remove the region from tracking - reporting a
+// missing free error after this one is redundant.
+void MacOSKeychainAPIChecker::
+ generateDeallocatorMismatchReport(const AllocationPair &AP,
+ const Expr *ArgExpr,
+ CheckerContext &C) const {
+ ProgramStateRef State = C.getState();
+ State = State->remove<AllocatedData>(AP.first);
+ ExplodedNode *N = C.addTransition(State);
+
+ if (!N)
+ return;
+ initBugType();
+ SmallString<80> sbuf;
+ llvm::raw_svector_ostream os(sbuf);
+ unsigned int PDeallocIdx =
+ FunctionsToTrack[AP.second->AllocatorIdx].DeallocatorIdx;
+
+ os << "Deallocator doesn't match the allocator: '"
+ << FunctionsToTrack[PDeallocIdx].Name << "' should be used.";
+ BugReport *Report = new BugReport(*BT, os.str(), N);
+ Report->addVisitor(new SecKeychainBugVisitor(AP.first));
+ Report->addRange(ArgExpr->getSourceRange());
+ markInteresting(Report, AP);
+ C.EmitReport(Report);
+}
+
+void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE,
+ CheckerContext &C) const {
+ unsigned idx = InvalidIdx;
+ ProgramStateRef State = C.getState();
+
+ StringRef funName = C.getCalleeName(CE);
+ if (funName.empty())
+ return;
+
+ // If it is a call to an allocator function, it could be a double allocation.
+ idx = getTrackedFunctionIndex(funName, true);
+ if (idx != InvalidIdx) {
+ const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param);
+ if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C))
+ if (const AllocationState *AS = State->get<AllocatedData>(V)) {
+ if (!definitelyReturnedError(AS->Region, State, C.getSValBuilder())) {
+ // Remove the value from the state. The new symbol will be added for
+ // tracking when the second allocator is processed in checkPostStmt().
+ State = State->remove<AllocatedData>(V);
+ ExplodedNode *N = C.addTransition(State);
+ if (!N)
+ return;
+ initBugType();
+ SmallString<128> sbuf;
+ llvm::raw_svector_ostream os(sbuf);
+ unsigned int DIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx;
+ os << "Allocated data should be released before another call to "
+ << "the allocator: missing a call to '"
+ << FunctionsToTrack[DIdx].Name
+ << "'.";
+ BugReport *Report = new BugReport(*BT, os.str(), N);
+ Report->addVisitor(new SecKeychainBugVisitor(V));
+ Report->addRange(ArgExpr->getSourceRange());
+ Report->markInteresting(AS->Region);
+ C.EmitReport(Report);
+ }
+ }
+ return;
+ }
+
+ // Is it a call to one of deallocator functions?
+ idx = getTrackedFunctionIndex(funName, false);
+ if (idx == InvalidIdx)
+ return;
+
+ // Check the argument to the deallocator.
+ const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param);
+ SVal ArgSVal = State->getSVal(ArgExpr, C.getLocationContext());
+
+ // Undef is reported by another checker.
+ if (ArgSVal.isUndef())
+ return;
+
+ SymbolRef ArgSM = ArgSVal.getAsLocSymbol();
+
+ // If the argument is coming from the heap, globals, or unknown, do not
+ // report it.
+ bool RegionArgIsBad = false;
+ if (!ArgSM) {
+ if (!isBadDeallocationArgument(ArgSVal.getAsRegion()))
+ return;
+ RegionArgIsBad = true;
+ }
+
+ // Is the argument to the call being tracked?
+ const AllocationState *AS = State->get<AllocatedData>(ArgSM);
+ if (!AS && FunctionsToTrack[idx].Kind != ValidAPI) {
+ return;
+ }
+ // If trying to free data which has not been allocated yet, report as a bug.
+ // TODO: We might want a more precise diagnostic for double free
+ // (that would involve tracking all the freed symbols in the checker state).
+ if (!AS || RegionArgIsBad) {
+ // It is possible that this is a false positive - the argument might
+ // have entered as an enclosing function parameter.
+ if (isEnclosingFunctionParam(ArgExpr))
+ return;
+
+ ExplodedNode *N = C.addTransition(State);
+ if (!N)
+ return;
+ initBugType();
+ BugReport *Report = new BugReport(*BT,
+ "Trying to free data which has not been allocated.", N);
+ Report->addRange(ArgExpr->getSourceRange());
+ if (AS)
+ Report->markInteresting(AS->Region);
+ C.EmitReport(Report);
+ return;
+ }
+
+ // Process functions which might deallocate.
+ if (FunctionsToTrack[idx].Kind == PossibleAPI) {
+
+ if (funName == "CFStringCreateWithBytesNoCopy") {
+ const Expr *DeallocatorExpr = CE->getArg(5)->IgnoreParenCasts();
+ // NULL ~ default deallocator, so warn.
+ if (DeallocatorExpr->isNullPointerConstant(C.getASTContext(),
+ Expr::NPC_ValueDependentIsNotNull)) {
+ const AllocationPair AP = std::make_pair(ArgSM, AS);
+ generateDeallocatorMismatchReport(AP, ArgExpr, C);
+ return;
+ }
+ // One of the default allocators, so warn.
+ if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(DeallocatorExpr)) {
+ StringRef DeallocatorName = DE->getFoundDecl()->getName();
+ if (DeallocatorName == "kCFAllocatorDefault" ||
+ DeallocatorName == "kCFAllocatorSystemDefault" ||
+ DeallocatorName == "kCFAllocatorMalloc") {
+ const AllocationPair AP = std::make_pair(ArgSM, AS);
+ generateDeallocatorMismatchReport(AP, ArgExpr, C);
+ return;
+ }
+ // If kCFAllocatorNull, which does not deallocate, we still have to
+ // find the deallocator. Otherwise, assume that the user had written a
+ // custom deallocator which does the right thing.
+ if (DE->getFoundDecl()->getName() != "kCFAllocatorNull") {
+ State = State->remove<AllocatedData>(ArgSM);
+ C.addTransition(State);
+ return;
+ }
+ }
+ }
+ return;
+ }
+
+ // The call is deallocating a value we previously allocated, so remove it
+ // from the next state.
+ State = State->remove<AllocatedData>(ArgSM);
+
+ // Check if the proper deallocator is used.
+ unsigned int PDeallocIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx;
+ if (PDeallocIdx != idx || (FunctionsToTrack[idx].Kind == ErrorAPI)) {
+ const AllocationPair AP = std::make_pair(ArgSM, AS);
+ generateDeallocatorMismatchReport(AP, ArgExpr, C);
+ return;
+ }
+
+ // If the buffer can be null and the return status can be an error,
+ // report a bad call to free.
+ if (State->assume(cast<DefinedSVal>(ArgSVal), false) &&
+ !definitelyDidnotReturnError(AS->Region, State, C.getSValBuilder())) {
+ ExplodedNode *N = C.addTransition(State);
+ if (!N)
+ return;
+ initBugType();
+ BugReport *Report = new BugReport(*BT,
+ "Only call free if a valid (non-NULL) buffer was returned.", N);
+ Report->addVisitor(new SecKeychainBugVisitor(ArgSM));
+ Report->addRange(ArgExpr->getSourceRange());
+ Report->markInteresting(AS->Region);
+ C.EmitReport(Report);
+ return;
+ }
+
+ C.addTransition(State);
+}
+
+void MacOSKeychainAPIChecker::checkPostStmt(const CallExpr *CE,
+ CheckerContext &C) const {
+ ProgramStateRef State = C.getState();
+ StringRef funName = C.getCalleeName(CE);
+
+ // If a value has been allocated, add it to the set for tracking.
+ unsigned idx = getTrackedFunctionIndex(funName, true);
+ if (idx == InvalidIdx)
+ return;
+
+ const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param);
+ // If the argument entered as an enclosing function parameter, skip it to
+ // avoid false positives.
+ if (isEnclosingFunctionParam(ArgExpr) &&
+ C.getLocationContext()->getParent() == 0)
+ return;
+
+ if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) {
+ // If the argument points to something that's not a symbolic region, it
+ // can be:
+ // - unknown (cannot reason about it)
+ // - undefined (already reported by other checker)
+ // - constant (null - should not be tracked,
+ // other constant will generate a compiler warning)
+ // - goto (should be reported by other checker)
+
+ // The call return value symbol should stay alive for as long as the
+ // allocated value symbol, since our diagnostics depend on the value
+ // returned by the call. Ex: Data should only be freed if noErr was
+ // returned during allocation.)
+ SymbolRef RetStatusSymbol =
+ State->getSVal(CE, C.getLocationContext()).getAsSymbol();
+ C.getSymbolManager().addSymbolDependency(V, RetStatusSymbol);
+
+ // Track the allocated value in the checker state.
+ State = State->set<AllocatedData>(V, AllocationState(ArgExpr, idx,
+ RetStatusSymbol));
+ assert(State);
+ C.addTransition(State);
+ }
+}
+
+void MacOSKeychainAPIChecker::checkPreStmt(const ReturnStmt *S,
+ CheckerContext &C) const {
+ const Expr *retExpr = S->getRetValue();
+ if (!retExpr)
+ return;
+
+ // If inside inlined call, skip it.
+ const LocationContext *LC = C.getLocationContext();
+ if (LC->getParent() != 0)
+ return;
+
+ // Check if the value is escaping through the return.
+ ProgramStateRef state = C.getState();
+ SymbolRef sym = state->getSVal(retExpr, LC).getAsLocSymbol();
+ if (!sym)
+ return;
+ state = state->remove<AllocatedData>(sym);
+
+ // Proceed from the new state.
+ C.addTransition(state);
+}
+
+// TODO: This logic is the same as in Malloc checker.
+const Stmt *
+MacOSKeychainAPIChecker::getAllocationSite(const ExplodedNode *N,
+ SymbolRef Sym,
+ CheckerContext &C) const {
+ const LocationContext *LeakContext = N->getLocationContext();
+ // Walk the ExplodedGraph backwards and find the first node that referred to
+ // the tracked symbol.
+ const ExplodedNode *AllocNode = N;
+
+ while (N) {
+ if (!N->getState()->get<AllocatedData>(Sym))
+ break;
+ // Allocation node, is the last node in the current context in which the
+ // symbol was tracked.
+ if (N->getLocationContext() == LeakContext)
+ AllocNode = N;
+ N = N->pred_empty() ? NULL : *(N->pred_begin());
+ }
+
+ ProgramPoint P = AllocNode->getLocation();
+ if (!isa<StmtPoint>(P))
+ return 0;
+ return cast<clang::PostStmt>(P).getStmt();
+}
+
+BugReport *MacOSKeychainAPIChecker::
+ generateAllocatedDataNotReleasedReport(const AllocationPair &AP,
+ ExplodedNode *N,
+ CheckerContext &C) const {
+ const ADFunctionInfo &FI = FunctionsToTrack[AP.second->AllocatorIdx];
+ initBugType();
+ SmallString<70> sbuf;
+ llvm::raw_svector_ostream os(sbuf);
+ os << "Allocated data is not released: missing a call to '"
+ << FunctionsToTrack[FI.DeallocatorIdx].Name << "'.";
+
+ // Most bug reports are cached at the location where they occurred.
+ // With leaks, we want to unique them by the location where they were
+ // allocated, and only report a single path.
+ PathDiagnosticLocation LocUsedForUniqueing;
+ if (const Stmt *AllocStmt = getAllocationSite(N, AP.first, C))
+ LocUsedForUniqueing = PathDiagnosticLocation::createBegin(AllocStmt,
+ C.getSourceManager(), N->getLocationContext());
+
+ BugReport *Report = new BugReport(*BT, os.str(), N, LocUsedForUniqueing);
+ Report->addVisitor(new SecKeychainBugVisitor(AP.first));
+ markInteresting(Report, AP);
+ return Report;
+}
+
+void MacOSKeychainAPIChecker::checkDeadSymbols(SymbolReaper &SR,
+ CheckerContext &C) const {
+ ProgramStateRef State = C.getState();
+ AllocatedSetTy ASet = State->get<AllocatedData>();
+ if (ASet.isEmpty())
+ return;
+
+ bool Changed = false;
+ AllocationPairVec Errors;
+ for (AllocatedSetTy::iterator I = ASet.begin(), E = ASet.end(); I != E; ++I) {
+ if (SR.isLive(I->first))
+ continue;
+
+ Changed = true;
+ State = State->remove<AllocatedData>(I->first);
+ // If the allocated symbol is null or if the allocation call might have
+ // returned an error, do not report.
+ if (State->getSymVal(I->first) ||
+ definitelyReturnedError(I->second.Region, State, C.getSValBuilder()))
+ continue;
+ Errors.push_back(std::make_pair(I->first, &I->second));
+ }
+ if (!Changed) {
+ // Generate the new, cleaned up state.
+ C.addTransition(State);
+ return;
+ }
+
+ static SimpleProgramPointTag Tag("MacOSKeychainAPIChecker : DeadSymbolsLeak");
+ ExplodedNode *N = C.addTransition(C.getState(), C.getPredecessor(), &Tag);
+
+ // Generate the error reports.
+ for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end();
+ I != E; ++I) {
+ C.EmitReport(generateAllocatedDataNotReleasedReport(*I, N, C));
+ }
+
+ // Generate the new, cleaned up state.
+ C.addTransition(State, N);
+}
+
+// TODO: Remove this after we ensure that checkDeadSymbols are always called.
+void MacOSKeychainAPIChecker::checkEndPath(CheckerContext &C) const {
+ ProgramStateRef state = C.getState();
+
+ // If inside inlined call, skip it.
+ if (C.getLocationContext()->getParent() != 0)
+ return;
+
+ AllocatedSetTy AS = state->get<AllocatedData>();
+ if (AS.isEmpty())
+ return;
+
+ // Anything which has been allocated but not freed (nor escaped) will be
+ // found here, so report it.
+ bool Changed = false;
+ AllocationPairVec Errors;
+ for (AllocatedSetTy::iterator I = AS.begin(), E = AS.end(); I != E; ++I ) {
+ Changed = true;
+ state = state->remove<AllocatedData>(I->first);
+ // If the allocated symbol is null or if error code was returned at
+ // allocation, do not report.
+ if (state->getSymVal(I.getKey()) ||
+ definitelyReturnedError(I->second.Region, state,
+ C.getSValBuilder())) {
+ continue;
+ }
+ Errors.push_back(std::make_pair(I->first, &I->second));
+ }
+
+ // If no change, do not generate a new state.
+ if (!Changed) {
+ C.addTransition(state);
+ return;
+ }
+
+ static SimpleProgramPointTag Tag("MacOSKeychainAPIChecker : EndPathLeak");
+ ExplodedNode *N = C.addTransition(C.getState(), C.getPredecessor(), &Tag);
+
+ // Generate the error reports.
+ for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end();
+ I != E; ++I) {
+ C.EmitReport(generateAllocatedDataNotReleasedReport(*I, N, C));
+ }
+
+ C.addTransition(state, N);
+}
+
+
+PathDiagnosticPiece *MacOSKeychainAPIChecker::SecKeychainBugVisitor::VisitNode(
+ const ExplodedNode *N,
+ const ExplodedNode *PrevN,
+ BugReporterContext &BRC,
+ BugReport &BR) {
+ const AllocationState *AS = N->getState()->get<AllocatedData>(Sym);
+ if (!AS)
+ return 0;
+ const AllocationState *ASPrev = PrevN->getState()->get<AllocatedData>(Sym);
+ if (ASPrev)
+ return 0;
+
+ // (!ASPrev && AS) ~ We started tracking symbol in node N, it must be the
+ // allocation site.
+ const CallExpr *CE = cast<CallExpr>(cast<StmtPoint>(N->getLocation())
+ .getStmt());
+ const FunctionDecl *funDecl = CE->getDirectCallee();
+ assert(funDecl && "We do not support indirect function calls as of now.");
+ StringRef funName = funDecl->getName();
+
+ // Get the expression of the corresponding argument.
+ unsigned Idx = getTrackedFunctionIndex(funName, true);
+ assert(Idx != InvalidIdx && "This should be a call to an allocator.");
+ const Expr *ArgExpr = CE->getArg(FunctionsToTrack[Idx].Param);
+ PathDiagnosticLocation Pos(ArgExpr, BRC.getSourceManager(),
+ N->getLocationContext());
+ return new PathDiagnosticEventPiece(Pos, "Data is allocated here.");
+}
+
+void ento::registerMacOSKeychainAPIChecker(CheckerManager &mgr) {
+ mgr.registerChecker<MacOSKeychainAPIChecker>();
+}