diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index 8c295f40d2ac..4281f3e0cf7f 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -275,12 +275,10 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size)
 
 	/* Setup the MTD structure */
 	/* make the name contain the block device in */
-	name = kmalloc(sizeof("block2mtd: ") + strlen(devname) + 1,
-			GFP_KERNEL);
+	name = kasprintf(GFP_KERNEL, "block2mtd: %s", devname);
 	if (!name)
 		goto devinit_err;
 
-	sprintf(name, "block2mtd: %s", devname);
 	dev->mtd.name = name;
 
 	dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK;