1 files changed, 140 insertions, 0 deletions
diff --git a/lib/Analysis/CallAndMessageChecker.cpp b/lib/Analysis/CallAndMessageChecker.cpp
new file mode 100644
index 0000000000..e717f6bfe2
--- /dev/null
+++ b/lib/Analysis/CallAndMessageChecker.cpp
@@ -0,0 +1,140 @@
+//===--- UndefinedArgChecker.h - Undefined arguments checker ----*- C++ -*--==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This defines BadCallChecker, a builtin check in GRExprEngine that performs
+// checks for undefined arguments.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/CheckerVisitor.h"
+#include "clang/Analysis/PathSensitive/BugReporter.h"
+#include "GRExprEngineInternalChecks.h"
+
+using namespace clang;
+
+namespace {
+class VISIBILITY_HIDDEN UndefinedArgChecker
+  : public CheckerVisitor<UndefinedArgChecker> {
+  BugType *BT_call_null;
+  BugType *BT_call_undef;  
+  BugType *BT_call_arg;
+  BugType *BT_msg_undef;
+  BugType *BT_msg_arg;
+public:
+  UndefinedArgChecker() :
+    BT_call_null(0), BT_call_undef(0), BT_call_arg(0),
+    BT_msg_undef(0), BT_msg_arg(0) {}
+  static void *getTag() {
+    static int x = 0;
+    return &x;
+  }
+  void PreVisitCallExpr(CheckerContext &C, const CallExpr *CE);
+  void PreVisitObjCMessageExpr(CheckerContext &C, const ObjCMessageExpr *ME);
+private:
+  void EmitBadCall(BugType *BT, CheckerContext &C, const CallExpr *CE);
+};
+} // end anonymous namespace
+
+void clang::RegisterUndefinedArgChecker(GRExprEngine &Eng) {
+  Eng.registerCheck(new UndefinedArgChecker());
+}
+
+void UndefinedArgChecker::EmitBadCall(BugType *BT, CheckerContext &C,
+                                      const CallExpr *CE) {
+  ExplodedNode *N = C.GenerateSink();
+  if (!N)
+    return;
+    
+  EnhancedBugReport *R = new EnhancedBugReport(*BT, BT->getName(), N);
+  R->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue,
+                       bugreporter::GetCalleeExpr(N));
+  C.EmitReport(R);
+}
+
+void UndefinedArgChecker::PreVisitCallExpr(CheckerContext &C, 
+                                           const CallExpr *CE){
+  
+  const Expr *Callee = CE->getCallee()->IgnoreParens();
+  SVal L = C.getState()->getSVal(Callee);
+  
+  if (L.isUndef()) {
+    if (!BT_call_undef)
+      BT_call_undef =
+        new BuiltinBug("Called function pointer is an undefined pointer value");
+    EmitBadCall(BT_call_undef, C, CE);
+    return;
+  }
+  
+  if (isa<loc::ConcreteInt>(L)) {
+    if (!BT_call_null)
+      BT_call_null =
+        new BuiltinBug("Called function pointer is null (null dereference)");
+    EmitBadCall(BT_call_null, C, CE);
+  }  
+  
+  for (CallExpr::const_arg_iterator I = CE->arg_begin(), E = CE->arg_end();
+       I != E; ++I) {
+    if (C.getState()->getSVal(*I).isUndef()) {
+      if (ExplodedNode *N = C.GenerateSink()) {
+        if (!BT_call_arg)
+          BT_call_arg = new BuiltinBug("Pass-by-value argument in function call"
+                                       " is undefined");
+        // Generate a report for this bug.
+        EnhancedBugReport *R = new EnhancedBugReport(*BT_call_arg,
+                                                     BT_call_arg->getName(), N);
+        R->addRange((*I)->getSourceRange());
+        R->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue, *I);
+        C.EmitReport(R);
+        return;
+      }
+    }
+  }
+}
+
+void UndefinedArgChecker::PreVisitObjCMessageExpr(CheckerContext &C,
+                                                  const ObjCMessageExpr *ME) {
+
+  const GRState *state = C.getState();
+
+  if (const Expr *receiver = ME->getReceiver())
+    if (state->getSVal(receiver).isUndef()) {
+      if (ExplodedNode *N = C.GenerateSink()) {
+        if (!BT_msg_undef)
+          BT_msg_undef =
+            new BuiltinBug("Receiver in message expression is a garbage value");
+        EnhancedBugReport *R =
+          new EnhancedBugReport(*BT_msg_undef, BT_msg_undef->getName(), N);
+        R->addRange(receiver->getSourceRange());
+        R->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue,
+                             receiver);
+        C.EmitReport(R);
+      }
+      return;
+    }
+
+  // Check for any arguments that are uninitialized/undefined.
+  for (ObjCMessageExpr::const_arg_iterator I = ME->arg_begin(), E = ME->arg_end();
+       I != E; ++I) {
+    if (state->getSVal(*I).isUndef()) {
+      if (ExplodedNode *N = C.GenerateSink()) {
+        if (!BT_msg_arg)
+          BT_msg_arg =
+            new BuiltinBug("Pass-by-value argument in message expression"
+                           " is undefined");      
+        // Generate a report for this bug.
+        EnhancedBugReport *R = new EnhancedBugReport(*BT_msg_arg,
+                                                     BT_msg_arg->getName(), N);
+        R->addRange((*I)->getSourceRange());
+        R->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue, *I);
+        C.EmitReport(R);
+        return;
+      }
+    }
+  }
+}