Fix EG(current_execute_data) introduced in 1292037

Fixes OSS-Fuzz #456317305

Author: iluuu1994

Zend/tests/oss_fuzz_456317305.phpt

@@ -0,0 +1,25 @@
+--TEST--
+OSS-Fuzz #456317305: EG(current_execute_data) NULL pointer violation
+--FILE--
+<?php
+
+class C {
+    public function __destruct() {
+        static $again = true;
+        if ($again) {
+            $again = false;
+            $c = new C;
+        }
+        throw new Exception;
+    }
+}
+
+$c = new C;
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Exception in %s:%d
+Stack trace:
+#0 [internal function]: C->__destruct()
+#1 {main}
+  thrown in %s on line %d

Zend/zend_generators.c

@@ -321,9 +321,11 @@ static void zend_generator_dtor_storage(zend_object *object) /* {{{ */
 			zend_object *old_exception = NULL;
 			const zend_op *old_opline_before_exception = NULL;
 			if (EG(exception)) {
-				EG(current_execute_data)->opline = EG(opline_before_exception);
+				if (EG(current_execute_data)) {
+					EG(current_execute_data)->opline = EG(opline_before_exception);
+					old_opline_before_exception = EG(opline_before_exception);
+				}
 				old_exception = EG(exception);
-				old_opline_before_exception = EG(opline_before_exception);
 				EG(exception) = NULL;
 			}
 
@@ -335,8 +337,10 @@ static void zend_generator_dtor_storage(zend_object *object) /* {{{ */
 			zend_generator_resume(generator);
 
 			if (old_exception) {
-				EG(current_execute_data)->opline = EG(exception_op);
-				EG(opline_before_exception) = old_opline_before_exception;
+				if (EG(current_execute_data)) {
+					EG(current_execute_data)->opline = EG(exception_op);
+					EG(opline_before_exception) = old_opline_before_exception;
+				}
 				if (EG(exception)) {
 					zend_exception_set_previous(EG(exception), old_exception);
 				} else {

Zend/zend_objects.c

@@ -100,7 +100,7 @@ ZEND_API void zend_objects_destroy_object(zend_object *object)
 
 	if (destructor) {
 		zend_object *old_exception;
-		const zend_op *old_opline_before_exception;
+		const zend_op *old_opline_before_exception = NULL;
 
 		if (destructor->op_array.fn_flags & (ZEND_ACC_PRIVATE|ZEND_ACC_PROTECTED)) {
 			if (destructor->op_array.fn_flags & ZEND_ACC_PRIVATE) {
@@ -159,23 +159,26 @@ ZEND_API void zend_objects_destroy_object(zend_object *object)
 			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));
+				if (EG(current_execute_data)) {
+					if (EG(current_execute_data)->func
+					 && ZEND_USER_CODE(EG(current_execute_data)->func->common.type)) {
+						zend_rethrow_exception(EG(current_execute_data));
+					}
+					EG(current_execute_data)->opline = EG(opline_before_exception);
+					old_opline_before_exception = EG(opline_before_exception);
 				}
-				EG(current_execute_data)->opline = EG(opline_before_exception);
 				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(current_execute_data)->opline = EG(exception_op);
-			EG(opline_before_exception) = old_opline_before_exception;
+			if (EG(current_execute_data)) {
+				EG(current_execute_data)->opline = EG(exception_op);
+				EG(opline_before_exception) = old_opline_before_exception;
+			}
 			if (EG(exception)) {
 				zend_exception_set_previous(EG(exception), old_exception);
 			} else {