[wasm] Add UTF-8 validation

src/wasm/wasm-module.cc

 // Copyright 2015 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 "src/macro-assembler.h"
 #include "src/objects.h"
 #include "src/property-descriptor.h"
 #include "src/v8.h"
 
 #include "src/simulator.h"
@@ skipping 538 matching lines @@
 
     // First pass: compile each function and initialize the code table.
     for (uint32_t i = FLAG_skip_compiling_wasm_funcs; i < functions.size();
          i++) {
       const WasmFunction& func = functions[i];
       if (thrower.error()) break;
       DCHECK_EQ(i, func.func_index);
 
       WasmName str = GetName(func.name_offset, func.name_length);
       WasmName str_null = {nullptr, 0};
-      Handle<String> name = factory->InternalizeUtf8String(str);
       Handle<Code> code = Handle<Code>::null();
       Handle<JSFunction> function = Handle<JSFunction>::null();
       if (func.external) {
         // Lookup external function in FFI object.
         MaybeHandle<JSFunction> function =
             LookupFunction(thrower, factory, ffi, i, str, str_null);
         if (function.is_null()) return MaybeHandle<JSObject>();
         code = compiler::CompileWasmToJSWrapper(isolate, &module_env,
                                                 function.ToHandleChecked(),
                                                 func.sig, str, str_null);
       } else {
         if (FLAG_wasm_parallel_compilation) {
           code = results[i];
         } else {
           // Compile the function.
           code = compiler::CompileWasmFunction(&thrower, isolate, &module_env,
                                                &func);
         }
         if (code.is_null()) {
           thrower.Error("Compilation of #%d:%.*s failed.", i, str.length(),
                         str.start());
           return MaybeHandle<JSObject>();
         }
         if (func.exported) {
+          Handle<String> name = factory->InternalizeUtf8String(str);
           function = compiler::CompileJSToWasmWrapper(
               isolate, &module_env, name, code, instance.js_object, i);
           record_code_size(function->code());
         }
       }
       if (!code.is_null()) {
         // Install the code into the linker table.
         linker.Finish(i, code);
         code_table->set(i, *code);
         record_code_size(*code);
       }
-      if (func.exported) {
+      if (!function.is_null()) {
         // Exported functions are installed as read-only properties on the
         // module.
         desc.set_value(function);
         Maybe<bool> status = JSReceiver::DefineOwnProperty(
-            isolate, instance.js_object, name, &desc, Object::THROW_ON_ERROR);
+            isolate, instance.js_object, JSFunction::GetName(function), &desc,

[titzer, 2016/05/12 08:29:14]

I think it's better to pull out the name handle instead of getting it from the
JSFunction here.

[Clemens Hammacher, 2016/05/12 11:21:41]

Done.

+            Object::THROW_ON_ERROR);
         if (!status.IsJust())
           thrower.Error("export of %.*s failed.", str.length(), str.start());
       }
     }
 
     // Second pass: patch all direct call sites.
     linker.Link(instance.function_table, this->function_table);
     instance.js_object->SetInternalField(kWasmModuleFunctionTable,
                                          Smi::FromInt(0));
 
@@ skipping 204 matching lines @@
       wasm->GetInternalField(kWasmFunctionNamesArray), wasm->GetIsolate());
   if (func_names_arr_obj->IsUndefined())
     return func_names_arr_obj;  // Return undefined.
   return GetWasmFunctionNameFromTable(
       Handle<ByteArray>::cast(func_names_arr_obj), func_index);
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8