filter cross context eval

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 "v8.h"
 
 #include "accessors.h"
@@ skipping 9766 matching lines @@
     // No callback set and code generation disallowed.
     return false;
   } else {
     // Callback set. Let it decide if code generation is allowed.
     VMState<EXTERNAL> state(isolate);
     return callback(v8::Utils::ToLocal(context));
   }
 }
 
 
+static Handle<JSFunction> FirstJSFunctionOnStack(Isolate* isolate) {
+  for (StackTraceFrameIterator it(isolate); !it.done(); it.Advance()) {
+    StackFrame* raw_frame = it.frame();
+    if (!raw_frame->is_java_script()) continue;
+    JavaScriptFrame* frame = JavaScriptFrame::cast(raw_frame);
+    List<FrameSummary> frames(FLAG_max_inlining_levels + 1);
+    frame->Summarize(&frames);
+    for (int i = frames.length() - 1; i >= 0; i--) {

[Toon Verwaest, 2014/05/27 15:15:43]

Why is this a for-loop? :)

[dcarney, 2014/05/27 15:45:11]

originally, i was filtering stuff out

+      return frames[i].function();
+    }
+  }
+  return Handle<JSFunction>();

[Toon Verwaest, 2014/05/27 15:15:43]

If you can return an empty handle, it should be a MaybeHandle according to the
new rules.

+}
+
+
 RUNTIME_FUNCTION(Runtime_CompileString) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(String, source, 0);
   CONVERT_BOOLEAN_ARG_CHECKED(function_literal_only, 1);
 
   // Extract native context.
   Handle<Context> context(isolate->context()->native_context());
 
+  // Filter cross security context calls.
+  {
+    Handle<JSFunction> fun = FirstJSFunctionOnStack(isolate);
+    if (fun.is_null() || !context->HasSameSecurityTokenAs(fun->context())) {
+      return isolate->heap()->undefined_value();
+    }
+  }
+
   // Check if native context allows code generation from
   // strings. Throw an exception if it doesn't.
   if (context->allow_code_gen_from_strings()->IsFalse() &&
       !CodeGenerationFromStringsAllowed(isolate, context)) {
     Handle<Object> error_message =
         context->ErrorMessageForCodeGenerationFromStrings();
     return isolate->Throw(*isolate->factory()->NewEvalError(
         "code_gen_from_strings", HandleVector<Object>(&error_message, 1)));
   }
 
@@ skipping 5365 matching lines @@
   }
   return NULL;
 }
 
 
 const Runtime::Function* Runtime::FunctionForId(Runtime::FunctionId id) {
   return &(kIntrinsicFunctions[static_cast<int>(id)]);
 }
 
 } }  // namespace v8::internal