diff --git a/source/ff.c b/source/ff.c
index c57a320..4293e38 100644
--- a/source/ff.c
+++ b/source/ff.c
@@ -4841,6 +4841,7 @@ FRESULT f_mkdir (
 {
 	FRESULT res;
 	DIR dj;
+	FFOBJID sobj;
 	FATFS *fs;
 	BYTE *dir;
 	DWORD dcl, pcl, tm;
@@ -4858,13 +4859,12 @@ FRESULT f_mkdir (
 			res = FR_INVALID_NAME;
 		}
 		if (res == FR_NO_FILE) {				/* Can create a new directory */
-			dcl = create_chain(&dj.obj, 0);		/* Allocate a cluster for the new directory table */
-			dj.obj.objsize = (DWORD)fs->csize * SS(fs);
+			sobj.fs = fs;						/* New object id to create a new chain */
+			dcl = create_chain(&sobj, 0);		/* Allocate a cluster for the new directory */
 			res = FR_OK;
 			if (dcl == 0) res = FR_DENIED;		/* No space to allocate a new cluster */
 			if (dcl == 1) res = FR_INT_ERR;
 			if (dcl == 0xFFFFFFFF) res = FR_DISK_ERR;
-			if (res == FR_OK) res = sync_window(fs);	/* Flush FAT */
 			tm = GET_FATTIME();
 			if (res == FR_OK) {					/* Initialize the new directory table */
 				res = dir_clear(fs, dcl);		/* Clean up the new table */
@@ -4889,8 +4889,8 @@ FRESULT f_mkdir (
 				if (fs->fs_type == FS_EXFAT) {	/* Initialize directory entry block */
 					st_dword(fs->dirbuf + XDIR_ModTime, tm);	/* Created time */
 					st_dword(fs->dirbuf + XDIR_FstClus, dcl);	/* Table start cluster */
-					st_dword(fs->dirbuf + XDIR_FileSize, (DWORD)dj.obj.objsize);	/* File size needs to be valid */
-					st_dword(fs->dirbuf + XDIR_ValidFileSize, (DWORD)dj.obj.objsize);
+					st_dword(fs->dirbuf + XDIR_FileSize, (DWORD)fs->csize * SS(fs));	/* File size needs to be valid */
+					st_dword(fs->dirbuf + XDIR_ValidFileSize, (DWORD)fs->csize * SS(fs));
 					fs->dirbuf[XDIR_GenFlags] = 3;				/* Initialize the object flag */
 					fs->dirbuf[XDIR_Attr] = AM_DIR;				/* Attribute */
 					res = store_xdir(&dj);