Index: uspace/srv/fs/fat/fat_fat.c
===================================================================
--- uspace/srv/fs/fat/fat_fat.c	(revision a31c1ccf8d9b7b51789fe844a26f430af6ae24bd)
+++ uspace/srv/fs/fat/fat_fat.c	(revision dfd77382ed9624f5671e5680cd92fad49f395b3a)
@@ -183,5 +183,5 @@
 
 	/* zero out already allocated space */
-	for (o = nodep->size - 1; o < pos && o < boundary;
+	for (o = nodep->size; o < pos && o < boundary;
 	    o = ALIGN_DOWN(o + bps, bps)) {
 	    	int flags = (o % bps == 0) ?