kfifo: kfifo_copy_{to,from}_user: fix copied bytes calculation

'copied' and 'len' are in bytes, while 'ret' is in elements, so we need to
multiply 'ret' with the size of one element to get the correct result.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/kfifo.c b/lib/kfifo.c
index 7b7f830..d79b9d2 100644
--- a/lib/kfifo.c
+++ b/lib/kfifo.c
@@ -215,7 +215,7 @@
 	 * incrementing the fifo->in index counter
 	 */
 	smp_wmb();
-	*copied = len - ret;
+	*copied = len - ret * esize;
 	/* return the number of elements which are not copied */
 	return ret;
 }
@@ -275,7 +275,7 @@
 	 * incrementing the fifo->out index counter
 	 */
 	smp_wmb();
-	*copied = len - ret;
+	*copied = len - ret * esize;
 	/* return the number of elements which are not copied */
 	return ret;
 }