php-src/Zend/zend_objects.c
Jakub Zelenka 53aa53f42f
Introduce Zend guard recursion protection
This PR introduces a new way of recursion protection in JSON, var_dump
and friends. It fixes issue in master for __debugInfo and also improves
perf for jsonSerializable in some cases. More info can be found in
GH-10020.

Closes GH-11812
2023-08-24 13:03:14 +01:00

307 lines
9.9 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: Andi Gutmans <andi@php.net> |
| Zeev Suraski <zeev@php.net> |
| Dmitry Stogov <dmitry@php.net> |
+----------------------------------------------------------------------+
*/
#include "zend.h"
#include "zend_globals.h"
#include "zend_variables.h"
#include "zend_API.h"
#include "zend_interfaces.h"
#include "zend_exceptions.h"
#include "zend_weakrefs.h"
static zend_always_inline void _zend_object_std_init(zend_object *object, zend_class_entry *ce)
{
GC_SET_REFCOUNT(object, 1);
GC_TYPE_INFO(object) = GC_OBJECT;
object->ce = ce;
object->handlers = ce->default_object_handlers;
object->properties = NULL;
zend_objects_store_put(object);
if (UNEXPECTED(ce->ce_flags & ZEND_ACC_USE_GUARDS)) {
zval *guard_value = object->properties_table + object->ce->default_properties_count;
ZVAL_UNDEF(guard_value);
Z_GUARD_P(guard_value) = 0;
}
}
ZEND_API void ZEND_FASTCALL zend_object_std_init(zend_object *object, zend_class_entry *ce)
{
_zend_object_std_init(object, ce);
}
ZEND_API void zend_object_std_dtor(zend_object *object)
{
zval *p, *end;
if (object->properties) {
if (EXPECTED(!(GC_FLAGS(object->properties) & IS_ARRAY_IMMUTABLE))) {
if (EXPECTED(GC_DELREF(object->properties) == 0)
&& EXPECTED(GC_TYPE(object->properties) != IS_NULL)) {
zend_array_destroy(object->properties);
}
}
}
p = object->properties_table;
if (EXPECTED(object->ce->default_properties_count)) {
end = p + object->ce->default_properties_count;
do {
if (Z_REFCOUNTED_P(p)) {
if (UNEXPECTED(Z_ISREF_P(p)) &&
(ZEND_DEBUG || ZEND_REF_HAS_TYPE_SOURCES(Z_REF_P(p)))) {
zend_property_info *prop_info = zend_get_property_info_for_slot(object, p);
if (ZEND_TYPE_IS_SET(prop_info->type)) {
ZEND_REF_DEL_TYPE_SOURCE(Z_REF_P(p), prop_info);
}
}
i_zval_ptr_dtor(p);
}
p++;
} while (p != end);
}
if (UNEXPECTED(object->ce->ce_flags & ZEND_ACC_USE_GUARDS)) {
if (EXPECTED(Z_TYPE_P(p) == IS_STRING)) {
zval_ptr_dtor_str(p);
} else if (Z_TYPE_P(p) == IS_ARRAY) {
HashTable *guards;
guards = Z_ARRVAL_P(p);
ZEND_ASSERT(guards != NULL);
zend_hash_destroy(guards);
FREE_HASHTABLE(guards);
}
}
if (UNEXPECTED(GC_FLAGS(object) & IS_OBJ_WEAKLY_REFERENCED)) {
zend_weakrefs_notify(object);
}
}
ZEND_API void zend_objects_destroy_object(zend_object *object)
{
zend_function *destructor = object->ce->destructor;
if (destructor) {
zend_object *old_exception;
const zend_op *old_opline_before_exception;
if (destructor->op_array.fn_flags & (ZEND_ACC_PRIVATE|ZEND_ACC_PROTECTED)) {
if (destructor->op_array.fn_flags & ZEND_ACC_PRIVATE) {
/* Ensure that if we're calling a private function, we're allowed to do so.
*/
if (EG(current_execute_data)) {
zend_class_entry *scope = zend_get_executed_scope();
if (object->ce != scope) {
zend_throw_error(NULL,
"Call to private %s::__destruct() from %s%s",
ZSTR_VAL(object->ce->name),
scope ? "scope " : "global scope",
scope ? ZSTR_VAL(scope->name) : ""
);
return;
}
} else {
zend_error(E_WARNING,
"Call to private %s::__destruct() from global scope during shutdown ignored",
ZSTR_VAL(object->ce->name));
return;
}
} else {
/* Ensure that if we're calling a protected function, we're allowed to do so.
*/
if (EG(current_execute_data)) {
zend_class_entry *scope = zend_get_executed_scope();
if (!zend_check_protected(zend_get_function_root_class(destructor), scope)) {
zend_throw_error(NULL,
"Call to protected %s::__destruct() from %s%s",
ZSTR_VAL(object->ce->name),
scope ? "scope " : "global scope",
scope ? ZSTR_VAL(scope->name) : ""
);
return;
}
} else {
zend_error(E_WARNING,
"Call to protected %s::__destruct() from global scope during shutdown ignored",
ZSTR_VAL(object->ce->name));
return;
}
}
}
GC_ADDREF(object);
/* Make sure that destructors are protected from previously thrown exceptions.
* For example, if an exception was thrown in a function and when the function's
* local variable destruction results in a destructor being called.
*/
old_exception = NULL;
if (EG(exception)) {
if (EG(exception) == object) {
zend_error_noreturn(E_CORE_ERROR, "Attempt to destruct pending exception");
} else {
if (EG(current_execute_data)
&& EG(current_execute_data)->func
&& ZEND_USER_CODE(EG(current_execute_data)->func->common.type)) {
zend_rethrow_exception(EG(current_execute_data));
}
old_exception = EG(exception);
old_opline_before_exception = EG(opline_before_exception);
EG(exception) = NULL;
}
}
zend_call_known_instance_method_with_0_params(destructor, object, NULL);
if (old_exception) {
EG(opline_before_exception) = old_opline_before_exception;
if (EG(exception)) {
zend_exception_set_previous(EG(exception), old_exception);
} else {
EG(exception) = old_exception;
}
}
OBJ_RELEASE(object);
}
}
ZEND_API zend_object* ZEND_FASTCALL zend_objects_new(zend_class_entry *ce)
{
zend_object *object = emalloc(sizeof(zend_object) + zend_object_properties_size(ce));
_zend_object_std_init(object, ce);
return object;
}
ZEND_API void ZEND_FASTCALL zend_objects_clone_members(zend_object *new_object, zend_object *old_object)
{
bool has_clone_method = old_object->ce->clone != NULL;
if (old_object->ce->default_properties_count) {
zval *src = old_object->properties_table;
zval *dst = new_object->properties_table;
zval *end = src + old_object->ce->default_properties_count;
do {
i_zval_ptr_dtor(dst);
ZVAL_COPY_VALUE_PROP(dst, src);
zval_add_ref(dst);
if (has_clone_method) {
/* Unconditionally add the IS_PROP_REINITABLE flag to avoid a potential cache miss of property_info */
Z_PROP_FLAG_P(dst) |= IS_PROP_REINITABLE;
}
if (UNEXPECTED(Z_ISREF_P(dst)) &&
(ZEND_DEBUG || ZEND_REF_HAS_TYPE_SOURCES(Z_REF_P(dst)))) {
zend_property_info *prop_info = zend_get_property_info_for_slot(new_object, dst);
if (ZEND_TYPE_IS_SET(prop_info->type)) {
ZEND_REF_ADD_TYPE_SOURCE(Z_REF_P(dst), prop_info);
}
}
src++;
dst++;
} while (src != end);
} else if (old_object->properties && !has_clone_method) {
/* fast copy */
if (EXPECTED(old_object->handlers == &std_object_handlers)) {
if (EXPECTED(!(GC_FLAGS(old_object->properties) & IS_ARRAY_IMMUTABLE))) {
GC_ADDREF(old_object->properties);
}
new_object->properties = old_object->properties;
return;
}
}
if (old_object->properties &&
EXPECTED(zend_hash_num_elements(old_object->properties))) {
zval *prop, new_prop;
zend_ulong num_key;
zend_string *key;
if (!new_object->properties) {
new_object->properties = zend_new_array(zend_hash_num_elements(old_object->properties));
zend_hash_real_init_mixed(new_object->properties);
} else {
zend_hash_extend(new_object->properties, new_object->properties->nNumUsed + zend_hash_num_elements(old_object->properties), 0);
}
HT_FLAGS(new_object->properties) |=
HT_FLAGS(old_object->properties) & HASH_FLAG_HAS_EMPTY_IND;
ZEND_HASH_MAP_FOREACH_KEY_VAL(old_object->properties, num_key, key, prop) {
if (Z_TYPE_P(prop) == IS_INDIRECT) {
ZVAL_INDIRECT(&new_prop, new_object->properties_table + (Z_INDIRECT_P(prop) - old_object->properties_table));
} else {
ZVAL_COPY_VALUE(&new_prop, prop);
zval_add_ref(&new_prop);
}
if (has_clone_method) {
/* Unconditionally add the IS_PROP_REINITABLE flag to avoid a potential cache miss of property_info */
Z_PROP_FLAG_P(&new_prop) |= IS_PROP_REINITABLE;
}
if (EXPECTED(key)) {
_zend_hash_append(new_object->properties, key, &new_prop);
} else {
zend_hash_index_add_new(new_object->properties, num_key, &new_prop);
}
} ZEND_HASH_FOREACH_END();
}
if (has_clone_method) {
GC_ADDREF(new_object);
zend_call_known_instance_method_with_0_params(new_object->ce->clone, new_object, NULL);
if (ZEND_CLASS_HAS_READONLY_PROPS(new_object->ce)) {
for (uint32_t i = 0; i < new_object->ce->default_properties_count; i++) {
zval* prop = OBJ_PROP_NUM(new_object, i);
/* Unconditionally remove the IS_PROP_REINITABLE flag to avoid a potential cache miss of property_info */
Z_PROP_FLAG_P(prop) &= ~IS_PROP_REINITABLE;
}
}
OBJ_RELEASE(new_object);
}
}
ZEND_API zend_object *zend_objects_clone_obj(zend_object *old_object)
{
zend_object *new_object;
/* assume that create isn't overwritten, so when clone depends on the
* overwritten one then it must itself be overwritten */
new_object = zend_objects_new(old_object->ce);
/* zend_objects_clone_members() expect the properties to be initialized. */
if (new_object->ce->default_properties_count) {
zval *p = new_object->properties_table;
zval *end = p + new_object->ce->default_properties_count;
do {
ZVAL_UNDEF(p);
p++;
} while (p != end);
}
zend_objects_clone_members(new_object, old_object);
return new_object;
}