prevent php from crashing when serializing circular data.

Shane Caraveo · Shane Caraveo · commit ff4dfc56f287 · 2001-07-11T05:57:18.000Z
This script produced the crash.
&lt;?
$hash["test_key"] = "test_value";
$hash["hash_key"] = &amp;$hash;
echo serialize($hash);
?&gt;
diff --git a/ext/standard/var.c b/ext/standard/var.c
@@ -342,6 +342,7 @@ PHPAPI void php_var_serialize(zval *buf, zval **struc, HashTable *var_hash)
 							FREE_ZVAL(d);
 							break;
 					}
+					if (data == struc) return;
 					php_var_serialize(buf, data, var_hash);
 				}
 			}

Original file line number	Diff line number	Diff line change
`@@ -342,6 +342,7 @@ PHPAPI void php_var_serialize(zval buf, zval struc, HashTable var_hash)`
`342`	`342`	`FREE_ZVAL(d);`
`343`	`343`	`break;`
`344`	`344`	`}`
	`345`	`+ if (data == struc) return;`
`345`	`346`	`php_var_serialize(buf, data, var_hash);`
`346`	`347`	`}`
`347`	`348`	`}`