Split libAnalysis into two libraries: libAnalysis and libChecker.
(1) libAnalysis is a generic analysis library that can be used by
Sema. It defines the CFG, basic dataflow analysis primitives, and
inexpensive flow-sensitive analyses (e.g. LiveVariables).
(2) libChecker contains the guts of the static analyzer, incuding the
path-sensitive analysis engine and domain-specific checks.
Now any clients that want to use the frontend to build their own tools
don't need to link in the entire static analyzer.
This change exposes various obvious cleanups that can be made to the
layout of files and headers in libChecker. More changes pending. :)
This change also exposed a layering violation between AnalysisContext
and MemRegion. BlockInvocationContext shouldn't explicitly know about
BlockDataRegions. For now I've removed the BlockDataRegion* from
BlockInvocationContext (removing context-sensitivity; although this
wasn't used yet). We need to have a better way to extend
BlockInvocationContext (and any LocationContext) to add
context-sensitivty.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94406 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/CastToStructChecker.cpp b/lib/Checker/CastToStructChecker.cpp
new file mode 100644
index 0000000..bef5bc2
--- /dev/null
+++ b/lib/Checker/CastToStructChecker.cpp
@@ -0,0 +1,77 @@
+//=== CastToStructChecker.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 CastToStructChecker, a builtin checker that checks for
+// cast from non-struct pointer to struct pointer.
+// This check corresponds to CWE-588.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Checker/PathSensitive/CheckerVisitor.h"
+#include "GRExprEngineInternalChecks.h"
+
+using namespace clang;
+
+namespace {
+class CastToStructChecker
+ : public CheckerVisitor<CastToStructChecker> {
+ BuiltinBug *BT;
+public:
+ CastToStructChecker() : BT(0) {}
+ static void *getTag();
+ void PreVisitCastExpr(CheckerContext &C, const CastExpr *B);
+};
+}
+
+void *CastToStructChecker::getTag() {
+ static int x;
+ return &x;
+}
+
+void CastToStructChecker::PreVisitCastExpr(CheckerContext &C,
+ const CastExpr *CE) {
+ const Expr *E = CE->getSubExpr();
+ ASTContext &Ctx = C.getASTContext();
+ QualType OrigTy = Ctx.getCanonicalType(E->getType());
+ QualType ToTy = Ctx.getCanonicalType(CE->getType());
+
+ PointerType *OrigPTy = dyn_cast<PointerType>(OrigTy.getTypePtr());
+ PointerType *ToPTy = dyn_cast<PointerType>(ToTy.getTypePtr());
+
+ if (!ToPTy || !OrigPTy)
+ return;
+
+ QualType OrigPointeeTy = OrigPTy->getPointeeType();
+ QualType ToPointeeTy = ToPTy->getPointeeType();
+
+ if (!ToPointeeTy->isStructureType())
+ return;
+
+ // We allow cast from void*.
+ if (OrigPointeeTy->isVoidType())
+ return;
+
+ // Now the cast-to-type is struct pointer, the original type is not void*.
+ if (!OrigPointeeTy->isRecordType()) {
+ if (ExplodedNode *N = C.GenerateNode()) {
+ if (!BT)
+ BT = new BuiltinBug("Cast from non-struct type to struct type",
+ "Casting a non-structure type to a structure type "
+ "and accessing a field can lead to memory access "
+ "errors or data corruption.");
+ RangedBugReport *R = new RangedBugReport(*BT,BT->getDescription(), N);
+ R->addRange(CE->getSourceRange());
+ C.EmitReport(R);
+ }
+ }
+}
+
+void clang::RegisterCastToStructChecker(GRExprEngine &Eng) {
+ Eng.registerCheck(new CastToStructChecker());
+}