Ensure that executable pages are properly guarded.

src/deoptimizer.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 433 matching lines @@
       data->eager_deoptimization_entry_code_ = CreateCode(type);
     }
     base = data->eager_deoptimization_entry_code_;
   } else {
     if (data->lazy_deoptimization_entry_code_ == NULL) {
       data->lazy_deoptimization_entry_code_ = CreateCode(type);
     }
     base = data->lazy_deoptimization_entry_code_;
   }
   return
-      static_cast<Address>(base->body()) + (id * table_entry_size_);
+      static_cast<Address>(base->area_start()) + (id * table_entry_size_);
 }
 
 
 int Deoptimizer::GetDeoptimizationId(Address addr, BailoutType type) {
   MemoryChunk* base = NULL;
   DeoptimizerData* data = Isolate::Current()->deoptimizer_data();
   if (type == EAGER) {
     base = data->eager_deoptimization_entry_code_;
   } else {
     base = data->lazy_deoptimization_entry_code_;
   }
   if (base == NULL ||
-      addr < base->body() ||
-      addr >= base->body() +
+      addr < base->area_start() ||
+      addr >= base->area_start() +
           (kNumberOfEntries * table_entry_size_)) {
     return kNotDeoptimizationEntry;
   }
   ASSERT_EQ(0,
-      static_cast<int>(addr - base->body()) % table_entry_size_);
-  return static_cast<int>(addr - base->body()) / table_entry_size_;
+      static_cast<int>(addr - base->area_start()) % table_entry_size_);
+  return static_cast<int>(addr - base->area_start()) / table_entry_size_;
 }
 
 
 int Deoptimizer::GetOutputInfo(DeoptimizationOutputData* data,
                                unsigned id,
                                SharedFunctionInfo* shared) {
   // TODO(kasperl): For now, we do a simple linear search for the PC
   // offset associated with the given node id. This should probably be
   // changed to a binary search.
   int length = data->DeoptPoints();
@@ skipping 660 matching lines @@
   masm.set_emit_debug_code(false);
   GenerateDeoptimizationEntries(&masm, kNumberOfEntries, type);
   CodeDesc desc;
   masm.GetCode(&desc);
   ASSERT(desc.reloc_size == 0);
 
   MemoryChunk* chunk =
       Isolate::Current()->memory_allocator()->AllocateChunk(desc.instr_size,
                                                             EXECUTABLE,
                                                             NULL);
+  ASSERT(chunk->area_size() >= desc.instr_size);
   if (chunk == NULL) {
     V8::FatalProcessOutOfMemory("Not enough memory for deoptimization table");
   }
-  memcpy(chunk->body(), desc.buffer, desc.instr_size);
-  CPU::FlushICache(chunk->body(), desc.instr_size);
+  memcpy(chunk->area_start(), desc.buffer, desc.instr_size);
+  CPU::FlushICache(chunk->area_start(), desc.instr_size);
   return chunk;
 }
 
 
 Code* Deoptimizer::FindDeoptimizingCodeFromAddress(Address addr) {
   DeoptimizingCodeListNode* node =
       Isolate::Current()->deoptimizer_data()->deoptimizing_code_list_;
   while (node != NULL) {
     if (node->code()->contains(addr)) return *node->code();
     node = node->next();
@@ skipping 463 matching lines @@
 
 void DeoptimizedFrameInfo::Iterate(ObjectVisitor* v) {
   v->VisitPointer(BitCast<Object**>(&function_));
   v->VisitPointers(parameters_, parameters_ + parameters_count_);
   v->VisitPointers(expression_stack_, expression_stack_ + expression_count_);
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal