Harden Runtime_LiveEditCheckAndDropActivations against unsafe args.

src/runtime.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdlib.h>
 #include <limits>
 
 #include "src/v8.h"
 
 #include "src/accessors.h"
@@ skipping 13485 matching lines @@
 // checks that none of them have activations on stacks (of any thread).
 // Returns array of the same length with corresponding results of
 // LiveEdit::FunctionPatchabilityStatus type.
 RUNTIME_FUNCTION(Runtime_LiveEditCheckAndDropActivations) {
   HandleScope scope(isolate);
   CHECK(isolate->debug()->live_edit_enabled());
   ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_array, 0);
   CONVERT_BOOLEAN_ARG_CHECKED(do_drop, 1);
   RUNTIME_ASSERT(shared_array->length()->IsSmi());
+  RUNTIME_ASSERT(shared_array->HasFastElements())
   int array_length = Smi::cast(shared_array->length())->value();
   for (int i = 0; i < array_length; i++) {
     Handle<Object> element =
         Object::GetElement(isolate, shared_array, i).ToHandleChecked();
     RUNTIME_ASSERT(
         element->IsJSValue() &&
         Handle<JSValue>::cast(element)->value()->IsSharedFunctionInfo());
   }
 
   return *LiveEdit::CheckAndDropActivations(shared_array, do_drop);
@@ skipping 1586 matching lines @@
   }
   return NULL;
 }
 
 
 const Runtime::Function* Runtime::FunctionForId(Runtime::FunctionId id) {
   return &(kIntrinsicFunctions[static_cast<int>(id)]);
 }
 
 } }  // namespace v8::internal