moxa: prevent opening unavailable ports

In moxa.c there are 32 minor numbers reserved for each device. The
number of ports actually available per device is stored in
moxa_board_conf->numPorts. This number is not considered in moxa_open().
Opening a port that is not available results in a kernel oops.
This patch adds a test to moxa_open() that prevents opening unavailable
ports.

Signed-off-by: Dirk Eibach <eibach@gdsys.de>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dirk Eibach 2009-06-11 14:56:44 +01:00 committed by Linus Torvalds
parent d7f8d437bd
commit f0e8527726

View file

@ -1184,6 +1184,11 @@ static int moxa_open(struct tty_struct *tty, struct file *filp)
return -ENODEV;
}
if (port % MAX_PORTS_PER_BOARD >= brd->numPorts) {
mutex_unlock(&moxa_openlock);
return -ENODEV;
}
ch = &brd->ports[port % MAX_PORTS_PER_BOARD];
ch->port.count++;
tty->driver_data = ch;