USB: serial: keyspan_pda: verify endpoints at probe

commit 5d9b0f859babe96175cd33d7162a9463a875ffde upstream.

Check for the expected endpoints in attach() and fail loudly if not
present.

Note that failing to do this appears to be benign since da280e3488
("USB: keyspan_pda: clean up write-urb busy handling") which prevents a
NULL-pointer dereference in write() by never marking a non-existent
write-urb as free.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2017-01-03 16:39:48 +01:00 committed by Greg Kroah-Hartman
parent c6aa86222e
commit 65d107038e

View file

@ -699,6 +699,19 @@ MODULE_FIRMWARE("keyspan_pda/keyspan_pda.fw");
MODULE_FIRMWARE("keyspan_pda/xircom_pgs.fw");
#endif
static int keyspan_pda_attach(struct usb_serial *serial)
{
unsigned char num_ports = serial->num_ports;
if (serial->num_bulk_out < num_ports ||
serial->num_interrupt_in < num_ports) {
dev_err(&serial->interface->dev, "missing endpoints\n");
return -ENODEV;
}
return 0;
}
static int keyspan_pda_port_probe(struct usb_serial_port *port)
{
@ -776,6 +789,7 @@ static struct usb_serial_driver keyspan_pda_device = {
.break_ctl = keyspan_pda_break_ctl,
.tiocmget = keyspan_pda_tiocmget,
.tiocmset = keyspan_pda_tiocmset,
.attach = keyspan_pda_attach,
.port_probe = keyspan_pda_port_probe,
.port_remove = keyspan_pda_port_remove,
};