Fix for bug #68710 (Use After Free Vulnerability in PHP's unserialize())

Conflicts:
	ext/standard/var_unserializer.c

Author: smalyshev

ext/standard/tests/strings/bug68710.phpt

@@ -0,0 +1,25 @@
+--TEST--
+Bug #68710 Use after free vulnerability in unserialize() (bypassing the
+CVE-2014-8142 fix)
+--FILE--
+<?php
+for ($i=4; $i<100; $i++) {
+    $m = new StdClass();
+
+    $u = array(1);
+
+    $m->aaa = array(1,2,&$u,4,5);
+    $m->bbb = 1;
+    $m->ccc = &$u;
+    $m->ddd = str_repeat("A", $i);
+
+    $z = serialize($m);
+    $z = str_replace("aaa", "123", $z);
+    $z = str_replace("bbb", "123", $z);
+    $y = unserialize($z);
+    $z = serialize($y);
+}
+?>
+===DONE===
+--EXPECTF--
+===DONE===

ext/standard/var_unserializer.c

@@ -343,7 +343,7 @@ static inline int process_nested_data(UNSERIALIZE_PARAMETER, HashTable *ht, long
 		} else {
 			/* object properties should include no integers */
 			convert_to_string(key);
-			if (zend_symtable_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
+			if (zend_hash_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
 				var_push_dtor(var_hash, old_data);
 			}
 			zend_hash_update(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, &data,

ext/standard/var_unserializer.re

@@ -347,7 +347,7 @@ static inline int process_nested_data(UNSERIALIZE_PARAMETER, HashTable *ht, long
 		} else {
 			/* object properties should include no integers */
 			convert_to_string(key);
-			if (zend_symtable_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
+			if (zend_hash_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
 				var_push_dtor(var_hash, old_data);
 			}
 			zend_hash_update(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, &data,