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>
This commit is contained in:
xypron.glpk@gmx.de 2017-04-15 15:05:46 +02:00 committed by Tom Rini
parent 6568c731c4
commit 73be5b3fa7

View File

@ -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;