[PATCH 3.16.y-ckt 41/94] iio: accel: sca3000: memory corruption in sca3000_read_first_n_hw_rb()

[Luis Henriques]

3.16.7-ckt20 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter at oracle.com>

commit eda7d0f38aaf50dbb2a2de15e8db386c4f6f65fc upstream.

"num_read" is in byte units but we are write u16s so we end up write
twice as much as intended.

Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: Jonathan Cameron <jic23 at kernel.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/staging/iio/accel/sca3000_ring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/iio/accel/sca3000_ring.c b/drivers/staging/iio/accel/sca3000_ring.c
index 198710651e0e..737ce026029b 100644
--- a/drivers/staging/iio/accel/sca3000_ring.c
+++ b/drivers/staging/iio/accel/sca3000_ring.c
@@ -116,7 +116,7 @@ static int sca3000_read_first_n_hw_rb(struct iio_buffer *r,
 	if (ret)
 		goto error_ret;
 
-	for (i = 0; i < num_read; i++)
+	for (i = 0; i < num_read / sizeof(u16); i++)
 		*(((u16 *)rx) + i) = be16_to_cpup((u16 *)rx + i);
 
 	if (copy_to_user(buf, rx, num_read))