hso: Fix crashes on close.

Moved serial_open_count in hso_serial_open to
prevent crashes owing to the serial structure being made NULL
when hso_serial_close is called even though hso_serial_open
returned -ENODEV, Alan Cox pointed out this happens,
also put in sanity check in hso_serial_close
to check for a valid serial structure which should prevent
the most reproducable crash in the driver when the hso device
is disconnected while in use.

Signed-off-by: Denis Joseph Barrow <D.Barow@option.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Denis Joseph Barrow 2008-11-25 00:27:50 -08:00 committed by David S. Miller
parent bab04c3adb
commit 4a3e818181

View file

@ -1235,6 +1235,11 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
}
mutex_lock(&serial->parent->mutex);
/* check for port already opened, if not set the termios */
/* The serial->open count needs to be here as hso_serial_close
* will be called even if hso_serial_open returns -ENODEV.
*/
serial->open_count++;
result = usb_autopm_get_interface(serial->parent->interface);
if (result < 0)
goto err_out;
@ -1246,8 +1251,6 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
tty->driver_data = serial;
serial->tty = tty;
/* check for port already opened, if not set the termios */
serial->open_count++;
if (serial->open_count == 1) {
tty->low_latency = 1;
serial->rx_state = RX_IDLE;
@ -1285,6 +1288,10 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
u8 usb_gone;
D1("Closing serial port");
if (serial == NULL || serial->magic != HSO_SERIAL_MAGIC) {
D1("invalid serial structure bailing out.\n");
return;
}
mutex_lock(&serial->parent->mutex);
usb_gone = serial->parent->usb_gone;