Index: sys/fs/msdosfs/denode.h
===================================================================
--- sys/fs/msdosfs/denode.h
+++ sys/fs/msdosfs/denode.h
@@ -194,6 +194,10 @@
 	 (dep)->de_FileSize = getulong((dp)->deFileSize), \
 	 (FAT32((dep)->de_pmp) ? DE_INTERNALIZE32((dep), (dp)) : 0))
 
+#define DE_EXTERNALIZE32(dp, dep)			\
+	putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16)
+#define DE_EXTERNALIZE16(dp, dep)			\
+	putushort((dp)->deHighClust, 0)
 #define DE_EXTERNALIZE(dp, dep)				\
 	(memcpy((dp)->deName, (dep)->de_Name, 11),	\
 	 (dp)->deAttributes = (dep)->de_Attributes,	\
@@ -207,7 +211,7 @@
 	 putushort((dp)->deStartCluster, (dep)->de_StartCluster), \
 	 putulong((dp)->deFileSize,			\
 	     ((dep)->de_Attributes & ATTR_DIRECTORY) ? 0 : (dep)->de_FileSize), \
-	 putushort((dp)->deHighClust, (dep)->de_StartCluster >> 16))
+	 (FAT32((dep)->de_pmp) ? DE_EXTERNALIZE32((dp), (dep)) : DE_EXTERNALIZE16((dp), (dep))))
 
 #if defined(_KERNEL) || defined(MAKEFS)