Add checker for CWE-587: Assignment of a Fixed Address to a Pointer.

llvm-svn: 86523

1 files changed, 69 insertions, 0 deletions

diff --git a/clang/lib/Analysis/FixedAddressChecker.cpp b/clang/lib/Analysis/FixedAddressChecker.cpp
new file mode 100644
index 00000000000..fff451aebc4
--- /dev/null
+++ b/clang/lib/Analysis/FixedAddressChecker.cpp
@@ -0,0 +1,69 @@
+//=== FixedAddressChecker.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 FixedAddressChecker, a builtin checker that checks for
+// assignment of a fixed address to a pointer.
+// This check corresponds to CWE-587.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/CheckerVisitor.h"
+#include "GRExprEngineInternalChecks.h"
+
+using namespace clang;
+
+namespace {
+class VISIBILITY_HIDDEN FixedAddressChecker 
+  : public CheckerVisitor<FixedAddressChecker> {
+  BuiltinBug *BT;
+public:
+  FixedAddressChecker() : BT(0) {}
+  static void *getTag();
+  void PreVisitBinaryOperator(CheckerContext &C, const BinaryOperator *B);
+};
+}
+
+void *FixedAddressChecker::getTag() {
+  static int x;
+  return &x;
+}
+
+void FixedAddressChecker::PreVisitBinaryOperator(CheckerContext &C,
+                                                 const BinaryOperator *B) {
+  // Using a fixed address is not portable because that address will probably
+  // not be valid in all environments or platforms.
+
+  if (B->getOpcode() != BinaryOperator::Assign)
+    return;
+
+  QualType T = B->getType();
+  if (!T->isPointerType())
+    return;
+
+  const GRState *state = C.getState();
+
+  SVal RV = state->getSVal(B->getRHS());
+
+  if (!RV.isConstant() || RV.isZeroConstant())
+    return;
+
+  if (ExplodedNode *N = C.GenerateNode(B)) {
+    if (!BT)
+      BT = new BuiltinBug("Use fixed address", 
+                          "Using a fixed address is not portable because that address will probably not be valid in all environments or platforms.");
+    RangedBugReport *R = new RangedBugReport(*BT, BT->getDescription().c_str(),
+                                             N);
+    R->addRange(B->getRHS()->getSourceRange());
+    C.EmitReport(R);
+  }
+}
+
+void clang::RegisterFixedAddressChecker(GRExprEngine &Eng) {
+  Eng.registerCheck(new FixedAddressChecker());
+}