diff --git a/fs/ext4/ext4_write.c b/fs/ext4/ext4_write.c
index c42add9a7ea95d09543b4938d42668ed03128e73..648a59672c31eec1fcd0b409a185eb079670004a 100644
--- a/fs/ext4/ext4_write.c
+++ b/fs/ext4/ext4_write.c
@@ -840,7 +840,7 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
 	unsigned int ibmap_idx;
 	struct ext_filesystem *fs = get_fs();
 	ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
-	memset(filename, 0x00, sizeof(filename));
+	memset(filename, 0x00, 256);
 
 	g_parent_inode = zalloc(sizeof(struct ext2_inode));
 	if (!g_parent_inode)