8282628: Potential memory leak in sun.font.FontConfigManager.getFontConfig()

Reviewed-by: stuefe, dholmes, aivanov

Author: zhengyu123

src/java.desktop/unix/native/common/awt/fontpath.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2022, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -935,8 +935,10 @@ Java_sun_font_FontConfigManager_getFontConfig
         if (cacheDirs != NULL) {
             while ((cnt < max) && (cacheDir = (*FcStrListNext)(cacheDirs))) {
                 jstr = (*env)->NewStringUTF(env, (const char*)cacheDir);
-                JNU_CHECK_EXCEPTION(env);
-
+                if (IS_NULL(jstr)) {
+                    (*FcStrListDone)(cacheDirs);
+                    return;
+                }
                 (*env)->SetObjectArrayElement(env, cacheDirArray, cnt++, jstr);
                 (*env)->DeleteLocalRef(env, jstr);
             }