8207750: Native handle leak in java.io.WinNTFileSystem.list()

Reviewed-by: bpb

src/windows/native/java/io/WinNTFileSystem_md.c

@@ -626,6 +626,7 @@ Java_java_io_WinNTFileSystem_list(JNIEnv *env, jobject this, jobject file)
     jstring name;
     jclass str_class;
     WCHAR *pathbuf;
+    DWORD err;
 
     str_class = JNU_ClassString(env);
     CHECK_NULL_RETURN(str_class, NULL);
@@ -687,8 +688,10 @@ Java_java_io_WinNTFileSystem_list(JNIEnv *env, jobject this, jobject file)
     len = 0;
     maxlen = 16;
     rv = (*env)->NewObjectArray(env, maxlen, str_class, NULL);
-    if (rv == NULL) // Couldn't allocate an array
+    if (rv == NULL) { // Couldn't allocate an array
+        FindClose(handle);
         return NULL;
+    }
     /* Scan the directory */
     do {
         if (!wcscmp(find_data.cFileName, L".")
@@ -696,13 +699,17 @@ Java_java_io_WinNTFileSystem_list(JNIEnv *env, jobject this, jobject file)
            continue;
         name = (*env)->NewString(env, find_data.cFileName,
                                  (jsize)wcslen(find_data.cFileName));
-        if (name == NULL)
-            return NULL; // error;
+        if (name == NULL) {
+            FindClose(handle);
+            return NULL; // error
+        }
         if (len == maxlen) {
             old = rv;
             rv = (*env)->NewObjectArray(env, maxlen <<= 1, str_class, NULL);
-            if (rv == NULL || JNU_CopyObjectArray(env, rv, old, len) < 0)
+            if (rv == NULL || JNU_CopyObjectArray(env, rv, old, len) < 0) {
+                FindClose(handle);
                 return NULL; // error
+            }
             (*env)->DeleteLocalRef(env, old);
         }
         (*env)->SetObjectArrayElement(env, rv, len++, name);
@@ -710,9 +717,11 @@ Java_java_io_WinNTFileSystem_list(JNIEnv *env, jobject this, jobject file)
 
     } while (FindNextFileW(handle, &find_data));
 
-    if (GetLastError() != ERROR_NO_MORE_FILES)
-        return NULL; // error
+    err = GetLastError();
     FindClose(handle);
+    if (err != ERROR_NO_MORE_FILES) {
+        return NULL; // error
+    }
 
     /* Copy the final results into an appropriately-sized array */
     old = rv;