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diff --git a/clang/lib/StaticAnalyzer/Checkers/ObjCContainersChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ObjCContainersChecker.cpp
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+//== ObjCContainersChecker.cpp - Path sensitive checker for CFArray *- C++ -*=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Performs path sensitive checks of Core Foundation static containers like
+// CFArray.
+// 1) Check for buffer overflows:
+// In CFArrayGetArrayAtIndex( myArray, index), if the index is outside the
+// index space of theArray (0 to N-1 inclusive (where N is the count of
+// theArray), the behavior is undefined.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ObjCMessage.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/AST/ParentMap.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class ObjCContainersChecker : public Checker< check::PreStmt<CallExpr>,
+ check::PostStmt<CallExpr> > {
+ mutable OwningPtr<BugType> BT;
+ inline void initBugType() const {
+ if (!BT)
+ BT.reset(new BugType("CFArray API",
+ categories::CoreFoundationObjectiveC));
+ }
+
+ inline SymbolRef getArraySym(const Expr *E, CheckerContext &C) const {
+ SVal ArrayRef = C.getState()->getSVal(E, C.getLocationContext());
+ SymbolRef ArraySym = ArrayRef.getAsSymbol();
+ return ArraySym;
+ }
+
+ void addSizeInfo(const Expr *Array, const Expr *Size,
+ CheckerContext &C) const;
+
+public:
+ /// A tag to id this checker.
+ static void *getTag() { static int Tag; return &Tag; }
+
+ void checkPostStmt(const CallExpr *CE, CheckerContext &C) const;
+ void checkPreStmt(const CallExpr *CE, CheckerContext &C) const;
+};
+} // end anonymous namespace
+
+// ProgramState trait - a map from array symbol to it's state.
+typedef llvm::ImmutableMap<SymbolRef, DefinedSVal> ArraySizeM;
+
+namespace { struct ArraySizeMap {}; }
+namespace clang { namespace ento {
+template<> struct ProgramStateTrait<ArraySizeMap>
+ : public ProgramStatePartialTrait<ArraySizeM > {
+ static void *GDMIndex() { return ObjCContainersChecker::getTag(); }
+};
+}}
+
+void ObjCContainersChecker::addSizeInfo(const Expr *Array, const Expr *Size,
+ CheckerContext &C) const {
+ ProgramStateRef State = C.getState();
+ SVal SizeV = State->getSVal(Size, C.getLocationContext());
+ // Undefined is reported by another checker.
+ if (SizeV.isUnknownOrUndef())
+ return;
+
+ // Get the ArrayRef symbol.
+ SVal ArrayRef = State->getSVal(Array, C.getLocationContext());
+ SymbolRef ArraySym = ArrayRef.getAsSymbol();
+ if (!ArraySym)
+ return;
+
+ C.addTransition(State->set<ArraySizeMap>(ArraySym, cast<DefinedSVal>(SizeV)));
+ return;
+}
+
+void ObjCContainersChecker::checkPostStmt(const CallExpr *CE,
+ CheckerContext &C) const {
+ StringRef Name = C.getCalleeName(CE);
+ if (Name.empty() || CE->getNumArgs() < 1)
+ return;
+
+ // Add array size information to the state.
+ if (Name.equals("CFArrayCreate")) {
+ if (CE->getNumArgs() < 3)
+ return;
+ // Note, we can visit the Create method in the post-visit because
+ // the CFIndex parameter is passed in by value and will not be invalidated
+ // by the call.
+ addSizeInfo(CE, CE->getArg(2), C);
+ return;
+ }
+
+ if (Name.equals("CFArrayGetCount")) {
+ addSizeInfo(CE->getArg(0), CE, C);
+ return;
+ }
+}
+
+void ObjCContainersChecker::checkPreStmt(const CallExpr *CE,
+ CheckerContext &C) const {
+ StringRef Name = C.getCalleeName(CE);
+ if (Name.empty() || CE->getNumArgs() < 2)
+ return;
+
+ // Check the array access.
+ if (Name.equals("CFArrayGetValueAtIndex")) {
+ ProgramStateRef State = C.getState();
+ // Retrieve the size.
+ // Find out if we saw this array symbol before and have information about it.
+ const Expr *ArrayExpr = CE->getArg(0);
+ SymbolRef ArraySym = getArraySym(ArrayExpr, C);
+ if (!ArraySym)
+ return;
+
+ const DefinedSVal *Size = State->get<ArraySizeMap>(ArraySym);
+
+ if (!Size)
+ return;
+
+ // Get the index.
+ const Expr *IdxExpr = CE->getArg(1);
+ SVal IdxVal = State->getSVal(IdxExpr, C.getLocationContext());
+ if (IdxVal.isUnknownOrUndef())
+ return;
+ DefinedSVal Idx = cast<DefinedSVal>(IdxVal);
+
+ // Now, check if 'Idx in [0, Size-1]'.
+ const QualType T = IdxExpr->getType();
+ ProgramStateRef StInBound = State->assumeInBound(Idx, *Size, true, T);
+ ProgramStateRef StOutBound = State->assumeInBound(Idx, *Size, false, T);
+ if (StOutBound && !StInBound) {
+ ExplodedNode *N = C.generateSink(StOutBound);
+ if (!N)
+ return;
+ initBugType();
+ BugReport *R = new BugReport(*BT, "Index is out of bounds", N);
+ R->addRange(IdxExpr->getSourceRange());
+ C.EmitReport(R);
+ return;
+ }
+ }
+}
+
+/// Register checker.
+void ento::registerObjCContainersChecker(CheckerManager &mgr) {
+ mgr.registerChecker<ObjCContainersChecker>();
+}