From 73be5b3fa73e329ad0d9e12db427cd665e1a483c Mon Sep 17 00:00:00 2001
From: "xypron.glpk@gmx.de" <xypron.glpk@gmx.de>
Date: Sat, 15 Apr 2017 15:05:46 +0200
Subject: [PATCH] usbtty: avoid potential NULL pointer dereference
If current_urb is NULL it should not be dereferenced.
The problem was indicated by cppcheck.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
---
drivers/serial/usbtty.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/serial/usbtty.c b/drivers/serial/usbtty.c
index 2e19813643..29799dce93 100644
--- a/drivers/serial/usbtty.c
+++ b/drivers/serial/usbtty.c
@@ -850,6 +850,13 @@ static int write_buffer (circbuf_t * buf)
struct urb *current_urb = NULL;
current_urb = next_urb (device_instance, endpoint);
+
+ if (!current_urb) {
+ TTYERR ("current_urb is NULL, buf->size %d\n",
+ buf->size);
+ return 0;
+ }
+
/* TX data still exists - send it now
*/
if(endpoint->sent < current_urb->actual_length){
@@ -871,12 +878,6 @@ static int write_buffer (circbuf_t * buf)
*/
while (buf->size > 0) {
- if (!current_urb) {
- TTYERR ("current_urb is NULL, buf->size %d\n",
- buf->size);
- return total;
- }
-
dest = (char*)current_urb->buffer +
current_urb->actual_length;
--
2.39.5