[patch 2/2 v2] USB: keyspan: add a sanity test on "len"

Dan Carpenter
2013-04-05T05:43:20Z

"len" comes from the USB transfer and it's probably correct. The thing
is that we already have similar checks like:

if (data[i] >= serial->num_ports) {

So adding a sanity test here matches the rest of the code and is a good
idea.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: No change. Rebased.

diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c
index 3d303f0..eb30d7b 100644
--- a/drivers/usb/serial/keyspan.c
+++ b/drivers/usb/serial/keyspan.c
@@ -727,14 +727,15 @@ static void usa49wg_indat_callback(struct urb *urb)
if ((data[i] & 0x80) = 0) {
/* no error on any byte */
i++;
- for (x = 1; x < len ; ++x)
+ for (x = 1; x < len && i < urb->actual_length; ++x)
tty_insert_flip_char(&port->port,
data[i++], 0);
} else {
/*
* some bytes had errors, every byte has status
*/
- for (x = 0; x + 1 < len; x += 2) {
+ for (x = 0; x + 1 < len &&
+ i + 1 < urb->actual_length; x += 2) {
int stat = data[i], flag = 0;

if (stat & RXERROR_OVERRUN)