diff --git a/src/system_info.c b/src/system_info.c
index 9be2b03..af7cb40 100644
--- a/src/system_info.c
+++ b/src/system_info.c
@@ -886,7 +886,7 @@ static int get_block_size_by_write(const char *path, int *block_size)
 
     snprintf(tmp_filename, sizeof(tmp_filename),
             "%s/.blksize-test.tmp", path);
-    if ((fd=open(tmp_filename, O_WRONLY | O_CREAT | O_DIRECT)) < 0) {
+    if ((fd=open(tmp_filename, O_WRONLY | O_CREAT | O_DIRECT, 0755)) < 0) {
         result = errno != 0 ? errno : ENOENT;
         logError("file: "__FILE__", line: %d, "
                 "open file %s fail, errno: %d, error info: %s",