Harden Function()'s parsing of function literals.

src/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 638 matching lines @@
     int beg_loc = scanner().location().beg_pos;
     ParseSourceElements(body, Token::EOS, info->is_eval(), true, &ok);
     if (ok && !top_scope_->is_classic_mode()) {
       CheckOctalLiteral(beg_loc, scanner().location().end_pos, &ok);
     }
 
     if (ok && is_extended_mode()) {
       CheckConflictingVarDeclarations(top_scope_, &ok);
     }
 
+    if (ok && info->parse_restriction() == ONLY_SINGLE_FUNCTION_LITERAL) {
+      if (body->length() != 1 ||
+          !body->at(0)->IsExpressionStatement() ||
+          !body->at(0)->AsExpressionStatement()->
+              expression()->IsFunctionLiteral()) {
+        ReportMessage("unable_to_parse", Vector<const char*>::empty());
+        ok = false;
+      }
+    }
+
     if (ok) {
       result = factory()->NewFunctionLiteral(
           no_name,
           top_scope_,
           body,
           function_state.materialized_literal_count(),
           function_state.expected_property_count(),
           function_state.handler_count(),
           function_state.only_simple_this_property_assignments(),
           function_state.this_property_assignments(),
@@ skipping 5263 matching lines @@
       ASSERT(info->isolate()->has_pending_exception());
     } else {
       result = parser.ParseProgram();
     }
   }
   info->SetFunction(result);
   return (result != NULL);
 }
 
 } }  // namespace v8::internal