Mercurial > hg > graal-compiler
view src/share/vm/memory/guardedMemory.cpp @ 21696:ca140f8c35be
Empty pointer stamps are also non-null.
author | Thomas Wuerthinger <thomas.wuerthinger@oracle.com> |
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date | Wed, 03 Jun 2015 14:08:29 +0200 |
parents | fa62fb12cdca |
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/* * 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/allocation.hpp" #include "memory/allocation.inline.hpp" #include "memory/guardedMemory.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(" PTR_FORMAT ") not associated to any memory", p2i(this)); return; } st->print_cr("GuardedMemory(" PTR_FORMAT ") base_addr=" PTR_FORMAT " tag=" PTR_FORMAT " user_size=" SIZE_FORMAT " user_data=" PTR_FORMAT, p2i(this), p2i(_base_addr), p2i(get_tag()), get_user_size(), p2i(get_user_ptr())); Guard* guard = get_head_guard(); st->print_cr(" Header guard @" PTR_FORMAT " is %s", p2i(guard), (guard->verify() ? "OK" : "BROKEN")); guard = get_tail_guard(); st->print_cr(" Trailer guard @" PTR_FORMAT " is %s", p2i(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"); break; } } // test code... #ifndef PRODUCT static void guarded_memory_test_check(void* p, size_t sz, void* tag) { assert(p != NULL, "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