USB: omninet: fix potential tty NULL dereference

Add check for return value of tty_port_tty_get,
since it can return NULL after port hangup that may happen anytime.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexey Khoroshilov 2012-09-13 22:56:55 +04:00 committed by Greg Kroah-Hartman
parent 17e6791082
commit 8321652ae2

View file

@ -185,10 +185,12 @@ static void omninet_read_bulk_callback(struct urb *urb)
if (urb->actual_length && header->oh_len) {
struct tty_struct *tty = tty_port_tty_get(&port->port);
tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
if (tty) {
tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
header->oh_len);
tty_flip_buffer_push(tty);
tty_kref_put(tty);
tty_flip_buffer_push(tty);
tty_kref_put(tty);
}
}
/* Continue trying to always read */