Fix #78762: Failing FFI::cast() may leak memory

We have to release objects when we're done with them.

Author: cmb69

NEWS

@@ -18,6 +18,7 @@ PHP NEWS
 - FFI:
  . Fixed bug #78716 (Function name mangling is wrong for some parameter 
  types). (cmb)
+ . Fixed bug #78762 (Failing FFI::cast() may leak memory). (cmb)
  . Implement FR #78270 (Support __vectorcall convention with FFI). (cmb)
 
 - FPM:

ext/ffi/ffi.c

@@ -3882,6 +3882,7 @@ ZEND_METHOD(FFI, cast) /* {{{ */
 cdata->ptr = &cdata->ptr_holder;
 cdata->ptr_holder = old_cdata->ptr;
 } else if (type->size > old_type->size) {
+zend_object_release(&cdata->std);
 zend_throw_error(zend_ffi_exception_ce, "attempt to cast to larger type");
 return;
 } else if (ptr != &old_cdata->ptr_holder) {

ext/ffi/tests/bug78762.phpt

@@ -0,0 +1,14 @@
+--TEST--
+Bug #78762 (Failing FFI::cast() may leak memory)
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+try {
+ FFI::cast('char[10]', FFI::new('char[1]'));
+} catch (FFI\Exception $ex) {
+ echo $ex->getMessage(), PHP_EOL;
+}
+?>
+--EXPECT--
+attempt to cast to larger type