--- /dev/null	2014-05-06 11:08:35.793057342 +0200
+++ new/src/share/vm/memory/guardedMemory.cpp	2014-05-06 14:10:05.749563127 +0200
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+#include "precompiled.hpp"
+#include "memory/guardedMemory.hpp"
+
+#include "memory/allocation.hpp"
+#include "memory/allocation.inline.hpp"
+#include "runtime/os.hpp"
+
+void* GuardedMemory::wrap_copy(const void* ptr, const size_t len, const void* tag) {
+  size_t total_sz = GuardedMemory::get_total_size(len);
+  void* outerp = os::malloc(total_sz, mtInternal);
+  if (outerp != NULL) {
+    GuardedMemory guarded(outerp, len, tag);
+    void* innerp = guarded.get_user_ptr();
+    memcpy(innerp, ptr, len);
+    return innerp;
+  }
+  return NULL; // OOM
+}
+
+bool GuardedMemory::free_copy(void* p) {
+  if (p == NULL) {
+    return true;
+  }
+  GuardedMemory guarded((u_char*)p);
+  bool verify_ok = guarded.verify_guards();
+
+  /* always attempt to free, pass problem on to any nested memchecker */
+  os::free(guarded.release_for_freeing());
+
+  return verify_ok;
+}
+
+void GuardedMemory::print_on(outputStream* st) const {
+  if (_base_addr == NULL) {
+    st->print_cr("GuardedMemory(" INTPTR_FORMAT ") not associated to any memory", this);
+    return;
+  }
+  st->print_cr("GuardedMemory(" INTPTR_FORMAT ") base_addr=" PTR_FORMAT
+      " tag=" PTR_FORMAT " user_size=" SIZE_FORMAT " user_data=" PTR_FORMAT,
+      this, _base_addr, get_tag(), get_user_size(), get_user_ptr());
+
+  Guard* guard = get_head_guard();
+  st->print_cr("  Header guard @" PTR_FORMAT " is %s", guard, (guard->verify() ? "OK" : "BROKEN"));
+  guard = get_tail_guard();
+  st->print_cr("  Trailer guard @" PTR_FORMAT " is %s", guard, (guard->verify() ? "OK" : "BROKEN"));
+
+  u_char udata = *get_user_ptr();
+  switch (udata) {
+  case uninitBlockPad:
+    st->print_cr("  User data appears unused");
+    break;
+  case freeBlockPad:
+    st->print_cr("  User data appears to have been freed");
+    break;
+  default:
+    st->print_cr("  User data appears to be in use");
+  }
+}
+
+// test code...
+
+#ifndef PRODUCT
+
+static void guarded_memory_test_check(void* p, size_t sz, void* tag) {
+  assert(p, "NULL pointer given to check");
+  u_char* c = (u_char*) p;
+  GuardedMemory guarded(c);
+  assert(guarded.get_tag() == tag, "Tag is not the same as supplied");
+  assert(guarded.get_user_ptr() == c, "User pointer is not the same as supplied");
+  assert(guarded.get_user_size() == sz, "User size is not the same as supplied");
+  assert(guarded.verify_guards(), "Guard broken");
+}
+
+void GuardedMemory::test_guarded_memory() {
+  // Test the basic characteristics...
+  size_t total_sz = GuardedMemory::get_total_size(1);
+  assert(total_sz > 1 && total_sz >= (sizeof(GuardHeader) + 1 + sizeof(Guard)), "Unexpected size");
+  u_char* basep = (u_char*) os::malloc(total_sz, mtInternal);
+
+  GuardedMemory guarded(basep, 1, (void*)0xf000f000);
+
+  assert(*basep == badResourceValue, "Expected guard in the form of badResourceValue");
+  u_char* userp = guarded.get_user_ptr();
+  assert(*userp == uninitBlockPad, "Expected uninitialized data in the form of uninitBlockPad");
+  guarded_memory_test_check(userp, 1, (void*)0xf000f000);
+
+  void* freep = guarded.release_for_freeing();
+  assert((u_char*)freep == basep, "Expected the same pointer guard was ");
+  assert(*userp == freeBlockPad, "Expected user data to be free block padded");
+  assert(!guarded.verify_guards(), "Expected failed");
+  os::free(freep);
+
+  // Test a number of odd sizes...
+  size_t sz = 0;
+  do {
+    void* p = os::malloc(GuardedMemory::get_total_size(sz), mtInternal);
+    void* up = guarded.wrap_with_guards(p, sz, (void*)1);
+    memset(up, 0, sz);
+    guarded_memory_test_check(up, sz, (void*)1);
+    os::free(guarded.release_for_freeing());
+    sz = (sz << 4) + 1;
+  } while (sz < (256 * 1024));
+
+  // Test buffer overrun into head...
+  basep = (u_char*) os::malloc(GuardedMemory::get_total_size(1), mtInternal);
+  guarded.wrap_with_guards(basep, 1);
+  *basep = 0;
+  assert(!guarded.verify_guards(), "Expected failure");
+  os::free(basep);
+
+  // Test buffer overrun into tail with a number of odd sizes...
+  sz = 1;
+  do {
+    void* p = os::malloc(GuardedMemory::get_total_size(sz), mtInternal);
+    void* up = guarded.wrap_with_guards(p, sz, (void*)1);
+    memset(up, 0, sz + 1); // Buffer-overwrite (within guard)
+    assert(!guarded.verify_guards(), "Guard was not broken as expected");
+    os::free(guarded.release_for_freeing());
+    sz = (sz << 4) + 1;
+  } while (sz < (256 * 1024));
+
+  // Test wrap_copy/wrap_free...
+  assert(GuardedMemory::free_copy(NULL), "Expected free NULL to be OK");
+
+  const char* str = "Check my bounds out";
+  size_t str_sz = strlen(str) + 1;
+  char* str_copy = (char*) GuardedMemory::wrap_copy(str, str_sz);
+  guarded_memory_test_check(str_copy, str_sz, NULL);
+  assert(strcmp(str, str_copy) == 0, "Not identical copy");
+  assert(GuardedMemory::free_copy(str_copy), "Free copy failed to verify");
+
+  void* no_data = NULL;
+  void* no_data_copy = GuardedMemory::wrap_copy(no_data, 0);
+  assert(GuardedMemory::free_copy(no_data_copy), "Expected valid guards even for no data copy");
+}
+
+#endif // !PRODUCT
+