Exemplo n.º 1
0
static void addParameterValuesToBindings(const StackFrameContext *CalleeCtx,
                                         CallEvent::BindingsTy &Bindings,
                                         SValBuilder &SVB,
                                         const CallEvent &Call,
                                         CallEvent::param_iterator I,
                                         CallEvent::param_iterator E) {
  MemRegionManager &MRMgr = SVB.getRegionManager();

  // If the function has fewer parameters than the call has arguments, we simply
  // do not bind any values to them.
  unsigned NumArgs = Call.getNumArgs();
  unsigned Idx = 0;
  for (; I != E && Idx < NumArgs; ++I, ++Idx) {
    const ParmVarDecl *ParamDecl = *I;
    assert(ParamDecl && "Formal parameter has no decl?");

    SVal ArgVal = Call.getArgSVal(Idx);
    if (!ArgVal.isUnknown()) {
      Loc ParamLoc = SVB.makeLoc(MRMgr.getVarRegion(ParamDecl, CalleeCtx));
      Bindings.push_back(std::make_pair(ParamLoc, ArgVal));
    }
  }

  // FIXME: Variadic arguments are not handled at all right now.
}
Exemplo n.º 2
0
void MPIChecker::checkDoubleNonblocking(const CallEvent &PreCallEvent,
                                        CheckerContext &Ctx) const {
  if (!FuncClassifier->isNonBlockingType(PreCallEvent.getCalleeIdentifier())) {
    return;
  }
  const MemRegion *const MR =
      PreCallEvent.getArgSVal(PreCallEvent.getNumArgs() - 1).getAsRegion();
  if (!MR)
    return;
  const ElementRegion *const ER = dyn_cast<ElementRegion>(MR);

  // The region must be typed, in order to reason about it.
  if (!isa<TypedRegion>(MR) || (ER && !isa<TypedRegion>(ER->getSuperRegion())))
    return;

  ProgramStateRef State = Ctx.getState();
  const Request *const Req = State->get<RequestMap>(MR);

  // double nonblocking detected
  if (Req && Req->CurrentState == Request::State::Nonblocking) {
    ExplodedNode *ErrorNode = Ctx.generateNonFatalErrorNode();
    BReporter.reportDoubleNonblocking(PreCallEvent, *Req, MR, ErrorNode,
                                      Ctx.getBugReporter());
    Ctx.addTransition(ErrorNode->getState(), ErrorNode);
  }
  // no error
  else {
    State = State->set<RequestMap>(MR, Request::State::Nonblocking);
    Ctx.addTransition(State);
  }
}
Exemplo n.º 3
0
void ObjCSelfInitChecker::checkPreCall(const CallEvent &CE,
                                       CheckerContext &C) const {
  // FIXME: A callback should disable checkers at the start of functions.
  if (!shouldRunOnFunctionOrMethod(dyn_cast<NamedDecl>(
                                 C.getCurrentAnalysisDeclContext()->getDecl())))
    return;

  ProgramStateRef state = C.getState();
  unsigned NumArgs = CE.getNumArgs();
  // If we passed 'self' as and argument to the call, record it in the state
  // to be propagated after the call.
  // Note, we could have just given up, but try to be more optimistic here and
  // assume that the functions are going to continue initialization or will not
  // modify self.
  for (unsigned i = 0; i < NumArgs; ++i) {
    SVal argV = CE.getArgSVal(i);
    if (isSelfVar(argV, C)) {
      unsigned selfFlags = getSelfFlags(state->getSVal(cast<Loc>(argV)), C);
      C.addTransition(state->set<PreCallSelfFlags>(selfFlags));
      return;
    } else if (hasSelfFlag(argV, SelfFlag_Self, C)) {
      unsigned selfFlags = getSelfFlags(argV, C);
      C.addTransition(state->set<PreCallSelfFlags>(selfFlags));
      return;
    }
  }
}
Exemplo n.º 4
0
void SimpleStreamChecker::checkPreCall(const CallEvent &Call,
                                       CheckerContext &C) const {
  initIdentifierInfo(C.getASTContext());

  if (!Call.isGlobalCFunction())
    return;

  if (Call.getCalleeIdentifier() != IIfclose)
    return;

  if (Call.getNumArgs() != 1)
    return;

  // Get the symbolic value corresponding to the file handle.
  SymbolRef FileDesc = Call.getArgSVal(0).getAsSymbol();
  if (!FileDesc)
    return;

  // Check if the stream has already been closed.
  ProgramStateRef State = C.getState();
  const StreamState *SS = State->get<StreamMap>(FileDesc);
  if (SS && SS->isClosed()) {
    reportDoubleClose(FileDesc, Call, C);
    return;
  }

  // Generate the next transition, in which the stream is closed.
  State = State->set<StreamMap>(FileDesc, StreamState::getClosed());
  C.addTransition(State);
}
Exemplo n.º 5
0
void ObjCSelfInitChecker::checkPostCall(const CallEvent &CE,
                                        CheckerContext &C) const {
  // FIXME: A callback should disable checkers at the start of functions.
  if (!shouldRunOnFunctionOrMethod(dyn_cast<NamedDecl>(
                                 C.getCurrentAnalysisDeclContext()->getDecl())))
    return;

  ProgramStateRef state = C.getState();
  SelfFlagEnum prevFlags = (SelfFlagEnum)state->get<PreCallSelfFlags>();
  if (!prevFlags)
    return;
  state = state->remove<PreCallSelfFlags>();

  unsigned NumArgs = CE.getNumArgs();
  for (unsigned i = 0; i < NumArgs; ++i) {
    SVal argV = CE.getArgSVal(i);
    if (isSelfVar(argV, C)) {
      // If the address of 'self' is being passed to the call, assume that the
      // 'self' after the call will have the same flags.
      // EX: log(&self)
      addSelfFlag(state, state->getSVal(cast<Loc>(argV)), prevFlags, C);
      return;
    } else if (hasSelfFlag(argV, SelfFlag_Self, C)) {
      // If 'self' is passed to the call by value, assume that the function
      // returns 'self'. So assign the flags, which were set on 'self' to the
      // return value.
      // EX: self = performMoreInitialization(self)
      addSelfFlag(state, CE.getReturnValue(), prevFlags, C);
      return;
    }
  }

  C.addTransition(state);
}
Exemplo n.º 6
0
void CallAndMessageChecker::checkPreCall(const CallEvent &Call,
                                         CheckerContext &C) const {
  ProgramStateRef State = C.getState();

  // If this is a call to a C++ method, check if the callee is null or
  // undefined.
  if (const CXXInstanceCall *CC = dyn_cast<CXXInstanceCall>(&Call)) {
    SVal V = CC->getCXXThisVal();
    if (V.isUndef()) {
      if (!BT_cxx_call_undef)
        BT_cxx_call_undef.reset(new BuiltinBug("Called C++ object pointer is "
                                               "uninitialized"));
      emitBadCall(BT_cxx_call_undef.get(), C, CC->getCXXThisExpr());
      return;
    }

    ProgramStateRef StNonNull, StNull;
    llvm::tie(StNonNull, StNull) =
        State->assume(V.castAs<DefinedOrUnknownSVal>());

    if (StNull && !StNonNull) {
      if (!BT_cxx_call_null)
        BT_cxx_call_null.reset(new BuiltinBug("Called C++ object pointer "
                                              "is null"));
      emitBadCall(BT_cxx_call_null.get(), C, CC->getCXXThisExpr());
      return;
    }

    State = StNonNull;
  }

  // Don't check for uninitialized field values in arguments if the
  // caller has a body that is available and we have the chance to inline it.
  // This is a hack, but is a reasonable compromise betweens sometimes warning
  // and sometimes not depending on if we decide to inline a function.
  const Decl *D = Call.getDecl();
  const bool checkUninitFields =
    !(C.getAnalysisManager().shouldInlineCall() && (D && D->getBody()));

  OwningPtr<BugType> *BT;
  if (isa<ObjCMethodCall>(Call))
    BT = &BT_msg_arg;
  else
    BT = &BT_call_arg;

  for (unsigned i = 0, e = Call.getNumArgs(); i != e; ++i)
    if (PreVisitProcessArg(C, Call.getArgSVal(i), Call.getArgSourceRange(i),
                           Call.getArgExpr(i), /*IsFirstArgument=*/i == 0,
                           checkUninitFields, Call, *BT))
      return;

  // If we make it here, record our assumptions about the callee.
  C.addTransition(State);
}
Exemplo n.º 7
0
void StackAddrEscapeChecker::checkPreCall(const CallEvent &Call,
                                          CheckerContext &C) const {
  if (!ChecksEnabled[CK_StackAddrAsyncEscapeChecker])
    return;
  if (!Call.isGlobalCFunction("dispatch_after") &&
      !Call.isGlobalCFunction("dispatch_async"))
    return;
  for (unsigned Idx = 0, NumArgs = Call.getNumArgs(); Idx < NumArgs; ++Idx) {
    if (const BlockDataRegion *B = dyn_cast_or_null<BlockDataRegion>(
            Call.getArgSVal(Idx).getAsRegion()))
      checkAsyncExecutedBlockCaptures(*B, C);
  }
}
Exemplo n.º 8
0
/// Diagnose if any of the arguments to CE have already been
/// dealloc'd.
void ObjCSuperDeallocChecker::diagnoseCallArguments(const CallEvent &CE,
                                                    CheckerContext &C) const {
  ProgramStateRef State = C.getState();
  unsigned ArgCount = CE.getNumArgs();
  for (unsigned I = 0; I < ArgCount; I++) {
    SymbolRef Sym = CE.getArgSVal(I).getAsSymbol();
    if (!Sym)
      continue;

    if (State->contains<CalledSuperDealloc>(Sym)) {
      reportUseAfterDealloc(Sym, StringRef(), CE.getArgExpr(I), C);
      return;
    }
  }
}
Exemplo n.º 9
0
/// If we are in -dealloc or -dealloc is on the stack, handle the call if it is
/// call to Block_release().
void ObjCDeallocChecker::checkPreCall(const CallEvent &Call,
                                      CheckerContext &C) const {
  const IdentifierInfo *II = Call.getCalleeIdentifier();
  if (II != Block_releaseII)
    return;

  if (Call.getNumArgs() != 1)
    return;

  SymbolRef ReleasedValue = Call.getArgSVal(0).getAsSymbol();
  if (!ReleasedValue)
    return;

  transitionToReleaseValue(C, ReleasedValue);
}
/// \return Bitvector marking non-null attributes.
static llvm::SmallBitVector getNonNullAttrs(const CallEvent &Call) {
  const Decl *FD = Call.getDecl();
  unsigned NumArgs = Call.getNumArgs();
  llvm::SmallBitVector AttrNonNull(NumArgs);
  for (const auto *NonNull : FD->specific_attrs<NonNullAttr>()) {
    if (!NonNull->args_size()) {
      AttrNonNull.set(0, NumArgs);
      break;
    }
    for (const ParamIdx &Idx : NonNull->args()) {
      unsigned IdxAST = Idx.getASTIndex();
      if (IdxAST >= NumArgs)
        continue;
      AttrNonNull.set(IdxAST);
    }
  }
  return AttrNonNull;
}
Exemplo n.º 11
0
void CallAndMessageChecker::checkPreCall(const CallEvent &Call,
                                         CheckerContext &C) const {
  // If this is a call to a C++ method, check if the callee is null or
  // undefined.
  // FIXME: Generalize this to CXXInstanceCall once it supports
  // getCXXThisVal().
  if (const CXXMemberCall *CC = dyn_cast<CXXMemberCall>(&Call)) {
    SVal V = CC->getCXXThisVal();
    if (V.isUndef()) {
      if (!BT_cxx_call_undef)
        BT_cxx_call_undef.reset(new BuiltinBug("Called C++ object pointer is "
                                               "uninitialized"));
      EmitBadCall(BT_cxx_call_undef.get(), C, CC->getOriginExpr());
      return;
    }
    if (V.isZeroConstant()) {
      if (!BT_cxx_call_null)
        BT_cxx_call_null.reset(new BuiltinBug("Called C++ object pointer "
                                              "is null"));
      EmitBadCall(BT_cxx_call_null.get(), C, CC->getOriginExpr());
      return;
    }
  }

  // Don't check for uninitialized field values in arguments if the
  // caller has a body that is available and we have the chance to inline it.
  // This is a hack, but is a reasonable compromise betweens sometimes warning
  // and sometimes not depending on if we decide to inline a function.
  const Decl *D = Call.getDecl();
  const bool checkUninitFields =
    !(C.getAnalysisManager().shouldInlineCall() && (D && D->getBody()));

  OwningPtr<BugType> *BT;
  if (isa<ObjCMethodCall>(Call))
    BT = &BT_msg_arg;
  else
    BT = &BT_call_arg;

  for (unsigned i = 0, e = Call.getNumArgs(); i != e; ++i)
    if (PreVisitProcessArg(C, Call.getArgSVal(i), Call.getArgSourceRange(i),
                           Call.getArgExpr(i), /*IsFirstArgument=*/i == 0,
                           checkUninitFields, Call, *BT))
      return;
}
void NonNullParamChecker::checkPreCall(const CallEvent &Call,
                                       CheckerContext &C) const {
  if (!Call.getDecl())
    return;

  llvm::SmallBitVector AttrNonNull = getNonNullAttrs(Call);
  unsigned NumArgs = Call.getNumArgs();

  ProgramStateRef state = C.getState();
  ArrayRef<ParmVarDecl*> parms = Call.parameters();

  for (unsigned idx = 0; idx < NumArgs; ++idx) {
    // For vararg functions, a corresponding parameter decl may not exist.
    bool HasParam = idx < parms.size();

    // Check if the parameter is a reference. We want to report when reference
    // to a null pointer is passed as a parameter.
    bool haveRefTypeParam =
        HasParam ? parms[idx]->getType()->isReferenceType() : false;
    bool haveAttrNonNull = AttrNonNull[idx];

    // Check if the parameter is also marked 'nonnull'.
    if (!haveAttrNonNull && HasParam)
      haveAttrNonNull = parms[idx]->hasAttr<NonNullAttr>();

    if (!haveAttrNonNull && !haveRefTypeParam)
      continue;

    // If the value is unknown or undefined, we can't perform this check.
    const Expr *ArgE = Call.getArgExpr(idx);
    SVal V = Call.getArgSVal(idx);
    auto DV = V.getAs<DefinedSVal>();
    if (!DV)
      continue;

    assert(!haveRefTypeParam || DV->getAs<Loc>());

    // Process the case when the argument is not a location.
    if (haveAttrNonNull && !DV->getAs<Loc>()) {
      // If the argument is a union type, we want to handle a potential
      // transparent_union GCC extension.
      if (!ArgE)
        continue;

      QualType T = ArgE->getType();
      const RecordType *UT = T->getAsUnionType();
      if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
        continue;

      auto CSV = DV->getAs<nonloc::CompoundVal>();

      // FIXME: Handle LazyCompoundVals?
      if (!CSV)
        continue;

      V = *(CSV->begin());
      DV = V.getAs<DefinedSVal>();
      assert(++CSV->begin() == CSV->end());
      // FIXME: Handle (some_union){ some_other_union_val }, which turns into
      // a LazyCompoundVal inside a CompoundVal.
      if (!V.getAs<Loc>())
        continue;

      // Retrieve the corresponding expression.
      if (const auto *CE = dyn_cast<CompoundLiteralExpr>(ArgE))
        if (const auto *IE = dyn_cast<InitListExpr>(CE->getInitializer()))
          ArgE = dyn_cast<Expr>(*(IE->begin()));
    }

    ConstraintManager &CM = C.getConstraintManager();
    ProgramStateRef stateNotNull, stateNull;
    std::tie(stateNotNull, stateNull) = CM.assumeDual(state, *DV);

    // Generate an error node.  Check for a null node in case
    // we cache out.
    if (stateNull && !stateNotNull) {
      if (ExplodedNode *errorNode = C.generateErrorNode(stateNull)) {

        std::unique_ptr<BugReport> R;
        if (haveAttrNonNull)
          R = genReportNullAttrNonNull(errorNode, ArgE);
        else if (haveRefTypeParam)
          R = genReportReferenceToNullPointer(errorNode, ArgE);

        // Highlight the range of the argument that was null.
        R->addRange(Call.getArgSourceRange(idx));

        // Emit the bug report.
        C.emitReport(std::move(R));
      }

      // Always return.  Either we cached out or we just emitted an error.
      return;
    }

    if (stateNull) {
      if (ExplodedNode *N = C.generateSink(stateNull, C.getPredecessor())) {
        ImplicitNullDerefEvent event = {
          V, false, N, &C.getBugReporter(),
          /*IsDirectDereference=*/haveRefTypeParam};
        dispatchEvent(event);
      }
    }

    // If a pointer value passed the check we should assume that it is
    // indeed not null from this point forward.
    state = stateNotNull;
  }

  // If we reach here all of the arguments passed the nonnull check.
  // If 'state' has been updated generated a new node.
  C.addTransition(state);
}
Exemplo n.º 13
0
void AttrNonNullChecker::checkPreCall(const CallEvent &Call,
                                      CheckerContext &C) const {
  const Decl *FD = Call.getDecl();
  if (!FD)
    return;

  const NonNullAttr *Att = FD->getAttr<NonNullAttr>();
  if (!Att)
    return;

  ProgramStateRef state = C.getState();

  // Iterate through the arguments of CE and check them for null.
  for (unsigned idx = 0, count = Call.getNumArgs(); idx != count; ++idx) {
    if (!Att->isNonNull(idx))
      continue;

    SVal V = Call.getArgSVal(idx);
    DefinedSVal *DV = dyn_cast<DefinedSVal>(&V);

    // If the value is unknown or undefined, we can't perform this check.
    if (!DV)
      continue;

    if (!isa<Loc>(*DV)) {
      // If the argument is a union type, we want to handle a potential
      // transparent_union GCC extension.
      const Expr *ArgE = Call.getArgExpr(idx);
      if (!ArgE)
        continue;

      QualType T = ArgE->getType();
      const RecordType *UT = T->getAsUnionType();
      if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
        continue;

      if (nonloc::CompoundVal *CSV = dyn_cast<nonloc::CompoundVal>(DV)) {
        nonloc::CompoundVal::iterator CSV_I = CSV->begin();
        assert(CSV_I != CSV->end());
        V = *CSV_I;
        DV = dyn_cast<DefinedSVal>(&V);
        assert(++CSV_I == CSV->end());
        if (!DV)
          continue;        
      } else {
        // FIXME: Handle LazyCompoundVals?
        continue;
      }
    }

    ConstraintManager &CM = C.getConstraintManager();
    ProgramStateRef stateNotNull, stateNull;
    llvm::tie(stateNotNull, stateNull) = CM.assumeDual(state, *DV);

    if (stateNull && !stateNotNull) {
      // Generate an error node.  Check for a null node in case
      // we cache out.
      if (ExplodedNode *errorNode = C.generateSink(stateNull)) {

        // Lazily allocate the BugType object if it hasn't already been
        // created. Ownership is transferred to the BugReporter object once
        // the BugReport is passed to 'EmitWarning'.
        if (!BT)
          BT.reset(new BugType("Argument with 'nonnull' attribute passed null",
                               "API"));

        BugReport *R =
          new BugReport(*BT, "Null pointer passed as an argument to a "
                             "'nonnull' parameter", errorNode);

        // Highlight the range of the argument that was null.
        R->addRange(Call.getArgSourceRange(idx));
        if (const Expr *ArgE = Call.getArgExpr(idx))
          bugreporter::addTrackNullOrUndefValueVisitor(errorNode, ArgE, R);
        // Emit the bug report.
        C.EmitReport(R);
      }

      // Always return.  Either we cached out or we just emitted an error.
      return;
    }

    // If a pointer value passed the check we should assume that it is
    // indeed not null from this point forward.
    assert(stateNotNull);
    state = stateNotNull;
  }

  // If we reach here all of the arguments passed the nonnull check.
  // If 'state' has been updated generated a new node.
  C.addTransition(state);
}
void CallAndMessageChecker::checkPreCall(const CallEvent &Call,
                                         CheckerContext &C) const {
  ProgramStateRef State = C.getState();

  // If this is a call to a C++ method, check if the callee is null or
  // undefined.
  if (const CXXInstanceCall *CC = dyn_cast<CXXInstanceCall>(&Call)) {
    SVal V = CC->getCXXThisVal();
    if (V.isUndef()) {
      if (!BT_cxx_call_undef)
        BT_cxx_call_undef.reset(
            new BuiltinBug(this, "Called C++ object pointer is uninitialized"));
      emitBadCall(BT_cxx_call_undef.get(), C, CC->getCXXThisExpr());
      return;
    }

    ProgramStateRef StNonNull, StNull;
    std::tie(StNonNull, StNull) =
        State->assume(V.castAs<DefinedOrUnknownSVal>());

    if (StNull && !StNonNull) {
      if (!BT_cxx_call_null)
        BT_cxx_call_null.reset(
            new BuiltinBug(this, "Called C++ object pointer is null"));
      emitBadCall(BT_cxx_call_null.get(), C, CC->getCXXThisExpr());
      return;
    }

    State = StNonNull;
  }

  const Decl *D = Call.getDecl();
  const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
  if (FD) {
    // If we have a declaration, we can make sure we pass enough parameters to
    // the function.
    unsigned Params = FD->getNumParams();
    if (Call.getNumArgs() < Params) {
      ExplodedNode *N = C.generateSink();
      if (!N)
        return;

      LazyInit_BT("Function call with too few arguments", BT_call_few_args);

      SmallString<512> Str;
      llvm::raw_svector_ostream os(Str);
      os << "Function taking " << Params << " argument"
         << (Params == 1 ? "" : "s") << " is called with less ("
         << Call.getNumArgs() << ")";

      C.emitReport(
          llvm::make_unique<BugReport>(*BT_call_few_args, os.str(), N));
    }
  }

  // Don't check for uninitialized field values in arguments if the
  // caller has a body that is available and we have the chance to inline it.
  // This is a hack, but is a reasonable compromise betweens sometimes warning
  // and sometimes not depending on if we decide to inline a function.
  const bool checkUninitFields =
    !(C.getAnalysisManager().shouldInlineCall() && (D && D->getBody()));

  std::unique_ptr<BugType> *BT;
  if (isa<ObjCMethodCall>(Call))
    BT = &BT_msg_arg;
  else
    BT = &BT_call_arg;

  for (unsigned i = 0, e = Call.getNumArgs(); i != e; ++i) {
    const ParmVarDecl *ParamDecl = nullptr;
    if(FD && i < FD->getNumParams())
      ParamDecl = FD->getParamDecl(i);
    if (PreVisitProcessArg(C, Call.getArgSVal(i), Call.getArgSourceRange(i),
                           Call.getArgExpr(i), /*IsFirstArgument=*/i == 0,
                           checkUninitFields, Call, *BT, ParamDecl))
      return;
  }

  // If we make it here, record our assumptions about the callee.
  C.addTransition(State);
}
Exemplo n.º 15
0
void PHPZPPCheckerImpl::checkPreCall(const CallEvent &Call,
                                     CheckerContext &C) const {
  initIdentifierInfo(C.getASTContext());

  unsigned offset;

  if (!Call.isGlobalCFunction())
    return;

  if (Call.getCalleeIdentifier() == IIzpp) {
    offset = 1;
  } else if (Call.getCalleeIdentifier() == IIzpp_ex) {
    offset = 2;
  } else if (Call.getCalleeIdentifier() == IIzpmp) {
    offset = 2;
  } else if (Call.getCalleeIdentifier() == IIzpmp_ex) {
    offset = 3;
  } else {
    return;
  }

  if (TSRMBuild) {
    ++offset;
  }

  if (Call.getNumArgs() <= offset)
    // Something is really weird - this should be caught by the compiler
    return;

  const StringLiteral *format_spec_sl =
      getCStringLiteral(Call.getArgSVal(offset));
  if (!format_spec_sl) {
    // TODO need a good way to report this, even though this is no error
    std::cout << "Couldn't get format string looked at offset " << offset << std::endl;
    Call.dump();
    return;
  }
  const StringRef format_spec = format_spec_sl->getBytes();

  // Call.dump();
  for (StringRef::const_iterator modifier = format_spec.begin(),
                                 last_mod = format_spec.end();
       modifier != last_mod; ++modifier) {
//std::cout << "  I am checking for " << *modifier << std::endl;
    const PHPTypeRange range = map.equal_range(*modifier);

    if (range.first == range.second) {
      BugReport *R = new BugReport(
          *InvalidModifierBugType,
          std::string("Unknown modifier '") + *modifier + "'", C.addTransition());
      C.emitReport(R);
      return;
    }

    for (PHPTypeMap::const_iterator type = range.first; type != range.second;
         ++type) {
      if (!type->second) {
        // Current modifier doesn't need an argument, these are special things
        // like |, ! or /
        continue;
      }
      ++offset;
//std::cout << "    I need a " << *type->second << " (" << offset << ")" << std::endl;
      if (Call.getNumArgs() <= offset) {
        BugReport *R = new BugReport(*WrongArgumentNumberBugType,
                                     "Too few arguments for format specified",
                                     C.addTransition());
        C.emitReport(R);
//std::cout << "!!!!I am missing args! " << Call.getNumArgs() << "<=" << offset << std::endl;
        return;
      }

      SVal val = Call.getArgSVal(offset);
      if (!compareTypeWithSVal(val, *type->second, C)) {
        // TODO: Move error reporting here?

        // Even if there is a type mismatch we can continue, most of the time
        // this should be a simple mistake by the user, in rare cases the user
        // missed an argument and will get many subsequent errors
      }
    }
  }

  if (Call.getNumArgs() > 1 + offset) {
    BugReport *R = new BugReport(*WrongArgumentNumberBugType,
                                 "Too many arguments for format specified",
                                 C.addTransition());
    R->markInteresting(Call.getArgSVal(offset));
    C.emitReport(R);
  }
}
/// This callback warns when a nullable pointer or a null value is passed to a
/// function that expects its argument to be nonnull.
void NullabilityChecker::checkPreCall(const CallEvent &Call,
                                      CheckerContext &C) const {
  if (!Call.getDecl())
    return;

  ProgramStateRef State = C.getState();
  if (State->get<InvariantViolated>())
    return;

  ProgramStateRef OrigState = State;

  unsigned Idx = 0;
  for (const ParmVarDecl *Param : Call.parameters()) {
    if (Param->isParameterPack())
      break;

    if (Idx >= Call.getNumArgs())
      break;

    const Expr *ArgExpr = Call.getArgExpr(Idx);
    auto ArgSVal = Call.getArgSVal(Idx++).getAs<DefinedOrUnknownSVal>();
    if (!ArgSVal)
      continue;

    if (!Param->getType()->isAnyPointerType() &&
        !Param->getType()->isReferenceType())
      continue;

    NullConstraint Nullness = getNullConstraint(*ArgSVal, State);

    Nullability RequiredNullability =
        getNullabilityAnnotation(Param->getType());
    Nullability ArgExprTypeLevelNullability =
        getNullabilityAnnotation(ArgExpr->getType());

    unsigned ParamIdx = Param->getFunctionScopeIndex() + 1;

    if (Filter.CheckNullPassedToNonnull && Nullness == NullConstraint::IsNull &&
        ArgExprTypeLevelNullability != Nullability::Nonnull &&
        RequiredNullability == Nullability::Nonnull &&
        isDiagnosableCall(Call)) {
      ExplodedNode *N = C.generateErrorNode(State);
      if (!N)
        return;

      SmallString<256> SBuf;
      llvm::raw_svector_ostream OS(SBuf);
      OS << (Param->getType()->isObjCObjectPointerType() ? "nil" : "Null");
      OS << " passed to a callee that requires a non-null " << ParamIdx
         << llvm::getOrdinalSuffix(ParamIdx) << " parameter";
      reportBugIfInvariantHolds(OS.str(), ErrorKind::NilPassedToNonnull, N,
                                nullptr, C,
                                ArgExpr, /*SuppressPath=*/false);
      return;
    }

    const MemRegion *Region = getTrackRegion(*ArgSVal);
    if (!Region)
      continue;

    const NullabilityState *TrackedNullability =
        State->get<NullabilityMap>(Region);

    if (TrackedNullability) {
      if (Nullness == NullConstraint::IsNotNull ||
          TrackedNullability->getValue() != Nullability::Nullable)
        continue;

      if (Filter.CheckNullablePassedToNonnull &&
          RequiredNullability == Nullability::Nonnull &&
          isDiagnosableCall(Call)) {
        ExplodedNode *N = C.addTransition(State);
        SmallString<256> SBuf;
        llvm::raw_svector_ostream OS(SBuf);
        OS << "Nullable pointer is passed to a callee that requires a non-null "
           << ParamIdx << llvm::getOrdinalSuffix(ParamIdx) << " parameter";
        reportBugIfInvariantHolds(OS.str(),
                                  ErrorKind::NullablePassedToNonnull, N,
                                  Region, C, ArgExpr, /*SuppressPath=*/true);
        return;
      }
      if (Filter.CheckNullableDereferenced &&
          Param->getType()->isReferenceType()) {
        ExplodedNode *N = C.addTransition(State);
        reportBugIfInvariantHolds("Nullable pointer is dereferenced",
                                  ErrorKind::NullableDereferenced, N, Region,
                                  C, ArgExpr, /*SuppressPath=*/true);
        return;
      }
      continue;
    }
    // No tracked nullability yet.
    if (ArgExprTypeLevelNullability != Nullability::Nullable)
      continue;
    State = State->set<NullabilityMap>(
        Region, NullabilityState(ArgExprTypeLevelNullability, ArgExpr));
  }
  if (State != OrigState)
    C.addTransition(State);
}
Exemplo n.º 17
0
void DoubleFetchChecker::checkPostCall(const CallEvent &Call,CheckerContext &Ctx) const {
	const IdentifierInfo *ID = Call.getCalleeIdentifier();
	std::cout<<"\n";
	std::cout<<"[checkPostCall]------call function:"<<ID->getName().str()<<std::endl;

	ProgramStateRef state = Ctx.getState();


	if(ID == NULL) {
		return;
	}
	unsigned int curTime = this->getCurTime(state);
	/*everytime copy_from_user is invoked,
	 *a new tainted is added to the taintList of the first Arg,
	 *which is the fetched value in kernel
	 */

	if (ID->getName() == "copy_from_user"){

		SVal Val0 = state->getSVal(Call.getArgExpr(0), Ctx.getLocationContext());
		SVal origin = state->getSVal(Call.getArgExpr(1), Ctx.getLocationContext());
		SVal len = state->getSVal(Call.getArgExpr(2), Ctx.getLocationContext());
		std::cout<<"[checkPostCall]---> Val0: "<<toStr(Val0)<<std::endl;
		std::cout<<"[checkPostCall]---> origin: "<<toStr(origin)<<std::endl;
		std::cout<<"[checkPostCall]---> len: "<<toStr(len)<<std::endl;
		/* here has to use val1 as the origin,
		 * since it is conveted from the actuall Expr
		 */
		state = this->addNewTaint(state, Val0, origin);

		/*after making change to time line, we need to increase the time */
		state = this->increTime(state);
		std::cout<<"[checkPostCall] timer++"<<std::endl;
		if(state != NULL)
			Ctx.addTransition(state);

	}



	if (ID->getName() == "get_user" || ID->getName() =="__get_user"){

			SVal arg0 = Call.getArgSVal(0);
			SVal arg1 = Call.getArgSVal(1);
			std::cout<<"--->arg0: "<<toStr(arg0)<<std::endl;
			std::cout<<"--->arg1: "<<toStr(arg1)<<std::endl;

			//const Expr* e0 = Call.getArgExpr(0);
			//const Expr* e1 =Call.getArgExpr(1);

			/* here has to use val1 as the origin,
			 * since it is conveted from the actuall Expr
			 */
			state = this->addNewTaint(state, arg0, arg1);

			/*after making change to time line, we need to increase the time */
			state = this->increTime(state);
			std::cout<<"[checkPostCall] timer++"<<std::endl;
			if(state != NULL)
				Ctx.addTransition(state);

	}
	if (ID->getName() == "malloc" || ID->getName() == "UserAllocPoolWithQuota") {
		int num = Call.getNumArgs();
		SVal arg = Call.getArgSVal(0);
		SVal ret = Call.getReturnValue();
		/*no need to check by time*/
		if (this->isValTainted(state, arg)){
			std::cout<<"[checkPostCall] arg of malloc is tainted."<<"\targ is:"<<toStr(arg)<<std::endl;
			//pass current taint taint to return value
			ProgramStateRef newstate = passTaints(state, arg, ret);
			if (newstate!=state && newstate != NULL){
				Ctx.addTransition(newstate);
				std::cout<<"[checkPostCall]add ret Taint finish, ret is: "<<toStr(ret)<<std::endl;
				showValTaints(newstate, ret, "--->ret: ");
			}
			else
				std::cout<<"[checkPostCall] add ret Taint failed,  ret is "<<toStr(ret)<<std::endl;
		}

		else{
			std::cout<<"[checkPostCall] arg of malloc not tainted."<<"\targ is:"<<toStr(arg)<<std::endl;
		}
	}
	//int num = Call.getNumArgs();
	//for(int i =0; i< num; i++){
	if (ID->getName() == "CMSG_COMPAT_ALIGN") {
			SVal arg = Call.getArgSVal(0);
			SVal ret = Call.getReturnValue();
			/*no need to check by time*/
			if (this->isValTainted(state, arg)){
				std::cout<<"[checkPostCall] arg of anyfunc is tainted."<<"\targ is:"<<toStr(arg)<<std::endl;
				//pass current taint taint to return value
				ProgramStateRef newstate = passTaints(state, arg, ret);
				if (newstate!=state && newstate != NULL){
					Ctx.addTransition(newstate);
					std::cout<<"[checkPostCall]add ret Taint finish, ret is: "<<toStr(ret)<<std::endl;
					showValTaints(newstate, ret, "--->ret: ");
					return;
				}
				else
					std::cout<<"[checkPostCall] add ret Taint failed,  ret is "<<toStr(ret)<<std::endl;
			}

			else{
				std::cout<<"[checkPostCall] arg of anyfunc not tainted."<<"\targ is:"<<toStr(arg)<<std::endl;
			}
	}

}
Exemplo n.º 18
0
void IteratorChecker::checkPostCall(const CallEvent &Call,
                                    CheckerContext &C) const {
  // Record new iterator positions and iterator position changes
  const auto *Func = dyn_cast_or_null<FunctionDecl>(Call.getDecl());
  if (!Func)
    return;

  if (Func->isOverloadedOperator()) {
    const auto Op = Func->getOverloadedOperator();
    if (isSimpleComparisonOperator(Op)) {
      if (const auto *InstCall = dyn_cast<CXXInstanceCall>(&Call)) {
        handleComparison(C, Call.getReturnValue(), InstCall->getCXXThisVal(),
                         Call.getArgSVal(0), Op);
      } else {
        handleComparison(C, Call.getReturnValue(), Call.getArgSVal(0),
                         Call.getArgSVal(1), Op);
      }
    }
  } else {
    const auto *OrigExpr = Call.getOriginExpr();
    if (!OrigExpr)
      return;

    if (!isIteratorType(Call.getResultType()))
      return;

    auto State = C.getState();
    // Already bound to container?
    if (getIteratorPosition(State, Call.getReturnValue()))
      return;

    if (const auto *InstCall = dyn_cast<CXXInstanceCall>(&Call)) {
      if (isEndCall(Func)) {
        handleEnd(C, OrigExpr, Call.getReturnValue(),
                  InstCall->getCXXThisVal());
        return;
      }
    }

    // Copy-like and move constructors
    if (isa<CXXConstructorCall>(&Call) && Call.getNumArgs() == 1) {
      if (const auto *Pos = getIteratorPosition(State, Call.getArgSVal(0))) {
        State = setIteratorPosition(State, Call.getReturnValue(), *Pos);
        if (cast<CXXConstructorDecl>(Func)->isMoveConstructor()) {
          State = removeIteratorPosition(State, Call.getArgSVal(0));
        }
        C.addTransition(State);
        return;
      }
    }

    // Assumption: if return value is an iterator which is not yet bound to a
    //             container, then look for the first iterator argument, and
    //             bind the return value to the same container. This approach
    //             works for STL algorithms.
    // FIXME: Add a more conservative mode
    for (unsigned i = 0; i < Call.getNumArgs(); ++i) {
      if (isIteratorType(Call.getArgExpr(i)->getType())) {
        if (const auto *Pos = getIteratorPosition(State, Call.getArgSVal(i))) {
          assignToContainer(C, OrigExpr, Call.getReturnValue(),
                            Pos->getContainer());
          return;
        }
      }
    }
  }
}
Exemplo n.º 19
0
// Checking for SecItemAdd and SecItemUpdate, no particular reason for assigning it to PostCall
void iOSAppSecLeakingLogsChecker::checkPostCall(const CallEvent &Call,
                                        CheckerContext &C) const 
{
  do
  {
    if ( !m_pInsecureInstBugType )
    {
      MSEC_DEBUG( "redwud: ", "!m_pInsecureInstBugType" ) ;
      break ;
    }

    initIdentifierInfo( C.getASTContext() ) ;

    //redwud: Obviously it is what it is
    if ( !Call.isGlobalCFunction() )
    {
      MSEC_DEBUG( "redwud: ", "!Call.isGlobalCFunction" ) ;
      break ;
    }

    const IdentifierInfo *pCalleeIdent = Call.getCalleeIdentifier() ; 

    unsigned iNumArgs = Call.getNumArgs() ; 

    //We do away with array because it's only two of them and it
    //will break the while..passing pattern  
    if ( pCalleeIdent != m_piiNSLog )
    {  
      if ( (pCalleeIdent != m_piiNSLogv) )
      {
        break ;
      }
      //FIXME: Workaround to evade 2nd and onward parameters of NSLogv
      //  Idea: Use identifier for slot from s
      iNumArgs = 1 ;
    }

    CSensitiveInfo &rSenInfo = CSensitiveInfo::create() ;
    SymbolRef pSymToCheck = NULL ; 
   
    // Go through each parameter unless find some sensitive info in one of them
    for ( unsigned iCtr = 0; (iCtr < iNumArgs) && (!pSymToCheck); iCtr++ )
    {
      const Expr *pExpr = Call.getArgExpr( iCtr ) ;
      StringRef szString ;
      StringRef szVarName ;

      CMSecCommon::getStrFromExpr( szString, pExpr, &szVarName ) ; 

      if ( szString.empty() ) // Nil is supported here, so no need to check
      {
//        MSEC_DEBUG( "redwud: ", "Empty string" ) ;
        continue ;
      }

      if ( !rSenInfo.isSensitive( szString.str() ) && !rSenInfo.isSensitive( szVarName.str() ) )
      {
//        MSEC_DEBUG( "redwud: ", "!Sensitive :" << szString << "Var name: " << szVarName ) ;
        continue ; 
      }

      // Get the symbolic value corresponding to the target parameter.
      pSymToCheck = Call.getArgSVal( iCtr ).getAsSymbol() ;
     
      //Force the issue
      if ( !pSymToCheck )
      {
        pSymToCheck = CMSecCommon::conjureSymbolRef() ;
      }
    }

    if ( !pSymToCheck )
    {
      break ;
    }

    ProgramStateRef pProgState = C.getState() ; 

    //Report this instance
    CMSecCommon::reportInsecureInstance( pSymToCheck, C, C.addTransition( pProgState )
      , *m_pInsecureInstBugType, m_szReportDesc ) ;
  
  } while ( _PASSING_ ) ;

}
Exemplo n.º 20
0
void NonNullParamChecker::checkPreCall(const CallEvent &Call,
                                       CheckerContext &C) const {
  const Decl *FD = Call.getDecl();
  if (!FD)
    return;

  const NonNullAttr *Att = FD->getAttr<NonNullAttr>();

  ProgramStateRef state = C.getState();

  CallEvent::param_type_iterator TyI = Call.param_type_begin(),
                                 TyE = Call.param_type_end();

  for (unsigned idx = 0, count = Call.getNumArgs(); idx != count; ++idx){

    // Check if the parameter is a reference. We want to report when reference
    // to a null pointer is passed as a paramter.
    bool haveRefTypeParam = false;
    if (TyI != TyE) {
      haveRefTypeParam = (*TyI)->isReferenceType();
      TyI++;
    }

    bool haveAttrNonNull = Att && Att->isNonNull(idx);
    if (!haveAttrNonNull) {
      // Check if the parameter is also marked 'nonnull'.
      ArrayRef<ParmVarDecl*> parms = Call.parameters();
      if (idx < parms.size())
        haveAttrNonNull = parms[idx]->hasAttr<NonNullAttr>();
    }

    if (!haveRefTypeParam && !haveAttrNonNull)
      continue;

    // If the value is unknown or undefined, we can't perform this check.
    const Expr *ArgE = Call.getArgExpr(idx);
    SVal V = Call.getArgSVal(idx);
    Optional<DefinedSVal> DV = V.getAs<DefinedSVal>();
    if (!DV)
      continue;

    // Process the case when the argument is not a location.
    assert(!haveRefTypeParam || DV->getAs<Loc>());

    if (haveAttrNonNull && !DV->getAs<Loc>()) {
      // If the argument is a union type, we want to handle a potential
      // transparent_union GCC extension.
      if (!ArgE)
        continue;

      QualType T = ArgE->getType();
      const RecordType *UT = T->getAsUnionType();
      if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
        continue;

      if (Optional<nonloc::CompoundVal> CSV =
              DV->getAs<nonloc::CompoundVal>()) {
        nonloc::CompoundVal::iterator CSV_I = CSV->begin();
        assert(CSV_I != CSV->end());
        V = *CSV_I;
        DV = V.getAs<DefinedSVal>();
        assert(++CSV_I == CSV->end());
        // FIXME: Handle (some_union){ some_other_union_val }, which turns into
        // a LazyCompoundVal inside a CompoundVal.
        if (!V.getAs<Loc>())
          continue;
        // Retrieve the corresponding expression.
        if (const CompoundLiteralExpr *CE = dyn_cast<CompoundLiteralExpr>(ArgE))
          if (const InitListExpr *IE =
                dyn_cast<InitListExpr>(CE->getInitializer()))
             ArgE = dyn_cast<Expr>(*(IE->begin()));

      } else {
        // FIXME: Handle LazyCompoundVals?
        continue;
      }
    }

    ConstraintManager &CM = C.getConstraintManager();
    ProgramStateRef stateNotNull, stateNull;
    std::tie(stateNotNull, stateNull) = CM.assumeDual(state, *DV);

    if (stateNull && !stateNotNull) {
      // Generate an error node.  Check for a null node in case
      // we cache out.
      if (ExplodedNode *errorNode = C.generateSink(stateNull)) {

        BugReport *R = 0;
        if (haveAttrNonNull)
          R = genReportNullAttrNonNull(errorNode, ArgE);
        else if (haveRefTypeParam)
          R = genReportReferenceToNullPointer(errorNode, ArgE);

        // Highlight the range of the argument that was null.
        R->addRange(Call.getArgSourceRange(idx));

        // Emit the bug report.
        C.emitReport(R);
      }

      // Always return.  Either we cached out or we just emitted an error.
      return;
    }

    // If a pointer value passed the check we should assume that it is
    // indeed not null from this point forward.
    assert(stateNotNull);
    state = stateNotNull;
  }

  // If we reach here all of the arguments passed the nonnull check.
  // If 'state' has been updated generated a new node.
  C.addTransition(state);
}
Exemplo n.º 21
0
/// This callback warns when a nullable pointer or a null value is passed to a
/// function that expects its argument to be nonnull.
void NullabilityChecker::checkPreCall(const CallEvent &Call,
                                      CheckerContext &C) const {
  if (!Call.getDecl())
    return;

  ProgramStateRef State = C.getState();
  if (State->get<PreconditionViolated>())
    return;

  ProgramStateRef OrigState = State;

  unsigned Idx = 0;
  for (const ParmVarDecl *Param : Call.parameters()) {
    if (Param->isParameterPack())
      break;

    const Expr *ArgExpr = nullptr;
    if (Idx < Call.getNumArgs())
      ArgExpr = Call.getArgExpr(Idx);
    auto ArgSVal = Call.getArgSVal(Idx++).getAs<DefinedOrUnknownSVal>();
    if (!ArgSVal)
      continue;

    if (!Param->getType()->isAnyPointerType() &&
        !Param->getType()->isReferenceType())
      continue;

    NullConstraint Nullness = getNullConstraint(*ArgSVal, State);

    Nullability ParamNullability = getNullabilityAnnotation(Param->getType());
    Nullability ArgStaticNullability =
        getNullabilityAnnotation(ArgExpr->getType());

    if (Filter.CheckNullPassedToNonnull && Nullness == NullConstraint::IsNull &&
        ArgStaticNullability != Nullability::Nonnull &&
        ParamNullability == Nullability::Nonnull) {
      ExplodedNode *N = C.generateErrorNode(State);
      if (!N)
        return;
      reportBugIfPreconditionHolds(ErrorKind::NilPassedToNonnull, N, nullptr, C,
                                   ArgExpr);
      return;
    }

    const MemRegion *Region = getTrackRegion(*ArgSVal);
    if (!Region)
      continue;

    const NullabilityState *TrackedNullability =
        State->get<NullabilityMap>(Region);

    if (TrackedNullability) {
      if (Nullness == NullConstraint::IsNotNull ||
          TrackedNullability->getValue() != Nullability::Nullable)
        continue;

      if (Filter.CheckNullablePassedToNonnull &&
          ParamNullability == Nullability::Nonnull) {
        ExplodedNode *N = C.addTransition(State);
        reportBugIfPreconditionHolds(ErrorKind::NullablePassedToNonnull, N,
                                     Region, C, ArgExpr, /*SuppressPath=*/true);
        return;
      }
      if (Filter.CheckNullableDereferenced &&
          Param->getType()->isReferenceType()) {
        ExplodedNode *N = C.addTransition(State);
        reportBugIfPreconditionHolds(ErrorKind::NullableDereferenced, N, Region,
                                     C, ArgExpr, /*SuppressPath=*/true);
        return;
      }
      continue;
    }
    // No tracked nullability yet.
    if (ArgStaticNullability != Nullability::Nullable)
      continue;
    State = State->set<NullabilityMap>(
        Region, NullabilityState(ArgStaticNullability, ArgExpr));
  }
  if (State != OrigState)
    C.addTransition(State);
}