php-src/Zend/zend_map_ptr.h
Nikita Popov 6434c93a27 Explicitly store real map ptr base
If we only store the biased pointer, the map ptr region will not
be recognized as reachable memory by leak checkers. This is
primarily problematic for fuzzing, because this is persistent
memory that may be reallocated during the request, without being
an actual leak.

Avoid this by simply storing both the real base pointer of the
allocation, as well as the biased base pointer used for accesses.
2021-08-26 12:29:44 +02:00

96 lines
3.6 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Dmitry Stogov <dmitry@php.net> |
+----------------------------------------------------------------------+
*/
#ifndef ZEND_MAP_PTR_H
#define ZEND_MAP_PTR_H
#include "zend_portability.h"
#define ZEND_MAP_PTR_KIND_PTR 0
#define ZEND_MAP_PTR_KIND_PTR_OR_OFFSET 1
//#if defined(ZTS) || defined(TSRM_WIN32)
# define ZEND_MAP_PTR_KIND ZEND_MAP_PTR_KIND_PTR_OR_OFFSET
//#else
//# define ZEND_MAP_PTR_KIND ZEND_MAP_PTR_KIND_PTR
//#endif
#define ZEND_MAP_PTR(ptr) \
ptr ## __ptr
#define ZEND_MAP_PTR_DEF(type, name) \
type * ZEND_MAP_PTR(name)
#define ZEND_MAP_PTR_OFFSET2PTR(offset) \
((void**)((char*)CG(map_ptr_base) + offset))
#define ZEND_MAP_PTR_PTR2OFFSET(ptr) \
((void*)(((char*)(ptr)) - ((char*)CG(map_ptr_base))))
#define ZEND_MAP_PTR_INIT(ptr, val) do { \
ZEND_MAP_PTR(ptr) = (val); \
} while (0)
#define ZEND_MAP_PTR_NEW(ptr) do { \
ZEND_MAP_PTR(ptr) = zend_map_ptr_new(); \
} while (0)
#if ZEND_MAP_PTR_KIND == ZEND_MAP_PTR_KIND_PTR
# define ZEND_MAP_PTR_NEW_OFFSET() \
((uint32_t)(uintptr_t)ZEND_MAP_PTR_PTR2OFFSET(zend_map_ptr_new()))
# define ZEND_MAP_PTR_GET(ptr) \
(*(ZEND_MAP_PTR(ptr)))
# define ZEND_MAP_PTR_GET_IMM(ptr) \
ZEND_MAP_PTR_GET(ptr)
# define ZEND_MAP_PTR_SET(ptr, val) do { \
(*(ZEND_MAP_PTR(ptr))) = (val); \
} while (0)
# define ZEND_MAP_PTR_SET_IMM(ptr, val) \
ZEND_MAP_PTR_SET(ptr, val)
# define ZEND_MAP_PTR_BIASED_BASE(real_base) \
(real_base)
#elif ZEND_MAP_PTR_KIND == ZEND_MAP_PTR_KIND_PTR_OR_OFFSET
# define ZEND_MAP_PTR_NEW_OFFSET() \
((uint32_t)(uintptr_t)zend_map_ptr_new())
# define ZEND_MAP_PTR_IS_OFFSET(ptr) \
(((uintptr_t)ZEND_MAP_PTR(ptr)) & 1L)
# define ZEND_MAP_PTR_GET(ptr) \
(*(ZEND_MAP_PTR_IS_OFFSET(ptr) ? \
ZEND_MAP_PTR_OFFSET2PTR((uintptr_t)ZEND_MAP_PTR(ptr)) : \
((void**)(ZEND_MAP_PTR(ptr)))))
# define ZEND_MAP_PTR_GET_IMM(ptr) \
(*ZEND_MAP_PTR_OFFSET2PTR((uintptr_t)ZEND_MAP_PTR(ptr)))
# define ZEND_MAP_PTR_SET(ptr, val) do { \
void **__p = (void**)(ZEND_MAP_PTR(ptr)); \
if (ZEND_MAP_PTR_IS_OFFSET(ptr)) { \
__p = ZEND_MAP_PTR_OFFSET2PTR((uintptr_t)ZEND_MAP_PTR(ptr)); \
} \
*__p = (val); \
} while (0)
# define ZEND_MAP_PTR_SET_IMM(ptr, val) do { \
void **__p = ZEND_MAP_PTR_OFFSET2PTR((uintptr_t)ZEND_MAP_PTR(ptr)); \
*__p = (val); \
} while (0)
# define ZEND_MAP_PTR_BIASED_BASE(real_base) \
((void*)(((uintptr_t)(real_base)) - 1))
#else
# error "Unknown ZEND_MAP_PTR_KIND"
#endif
ZEND_API void zend_map_ptr_reset(void);
ZEND_API void *zend_map_ptr_new(void);
ZEND_API void zend_map_ptr_extend(size_t last);
ZEND_API void zend_alloc_ce_cache(zend_string *type_name);
#endif /* ZEND_MAP_PTR_H */