Commit 51370e5b authored by Tilman Schmidt's avatar Tilman Schmidt Committed by David S. Miller
Browse files

gigaset: in file ops, check for device disconnect before anything else 



When the device is disconnected, the dev structure goes away, so
trying to report another error via dev_printk is bound to oops.
To avoid that, first check whether the device is still connected
and return quietly if it isn't.

Impact: error handling

Signed-off-by: default avatarTilman Schmidt <tilman@imap.cc>
Reported-by: default avatarPaul Bolle <pebolle@tiscali.nl>
Tested-by: default avatarPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 368fd81d

drivers/isdn/gigaset/interface.c

+30 −28
Original line number Diff line number Diff line
@@ -193,7 +193,9 @@ static void if_close(struct tty_struct *tty, struct file *filp) 


	mutex_lock(&cs->mutex);



	if (!cs->open_count)

	if (!cs->connected)

		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */

	else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else {

		if (!--cs->open_count) {
@@ -228,7 +230,10 @@ static int if_ioctl(struct tty_struct *tty, struct file *file, 
	if (mutex_lock_interruptible(&cs->mutex))

		return -ERESTARTSYS; // FIXME -EINTR?



	if (!cs->open_count)

	if (!cs->connected) {

		gig_dbg(DEBUG_IF, "not connected");

		retval = -ENODEV;

	} else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else {

		retval = 0;
@@ -248,13 +253,6 @@ static int if_ioctl(struct tty_struct *tty, struct file *file, 
				retval = put_user(int_arg, (int __user *) arg);

			break;

		case GIGASET_BRKCHARS:

			//FIXME test if MS_LOCKED

			if (!cs->connected) {

				gig_dbg(DEBUG_ANY,

				    "can't communicate with unplugged device");

				retval = -ENODEV;

				break;

			}

			retval = copy_from_user(&buf,

					(const unsigned char __user *) arg, 6)

				? -EFAULT : 0;
@@ -331,7 +329,7 @@ static int if_tiocmset(struct tty_struct *tty, struct file *file, 
		return -ERESTARTSYS; // FIXME -EINTR?



	if (!cs->connected) {

		gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");

		gig_dbg(DEBUG_IF, "not connected");

		retval = -ENODEV;

	} else {

		mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
@@ -360,14 +358,14 @@ static int if_write(struct tty_struct *tty, const unsigned char *buf, int count) 
	if (mutex_lock_interruptible(&cs->mutex))

		return -ERESTARTSYS; // FIXME -EINTR?



	if (!cs->open_count)

	if (!cs->connected) {

		gig_dbg(DEBUG_IF, "not connected");

		retval = -ENODEV;

	} else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else if (cs->mstate != MS_LOCKED) {

		dev_warn(cs->dev, "can't write to unlocked device\n");

		retval = -EBUSY;

	} else if (!cs->connected) {

		gig_dbg(DEBUG_ANY, "can't write to unplugged device");

		retval = -EBUSY; //FIXME

	} else {

		retval = cs->ops->write_cmd(cs, buf, count,

					    &cs->if_wake_tasklet);
@@ -394,14 +392,14 @@ static int if_write_room(struct tty_struct *tty) 
	if (mutex_lock_interruptible(&cs->mutex))

		return -ERESTARTSYS; // FIXME -EINTR?



	if (!cs->open_count)

	if (!cs->connected) {

		gig_dbg(DEBUG_IF, "not connected");

		retval = -ENODEV;

	} else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else if (cs->mstate != MS_LOCKED) {

		dev_warn(cs->dev, "can't write to unlocked device\n");

		retval = -EBUSY;

	} else if (!cs->connected) {

		gig_dbg(DEBUG_ANY, "can't write to unplugged device");

		retval = -EBUSY; //FIXME

	} else

		retval = cs->ops->write_room(cs);
@@ -426,14 +424,14 @@ static int if_chars_in_buffer(struct tty_struct *tty) 
	if (mutex_lock_interruptible(&cs->mutex))

		return -ERESTARTSYS; // FIXME -EINTR?



	if (!cs->open_count)

	if (!cs->connected) {

		gig_dbg(DEBUG_IF, "not connected");

		retval = -ENODEV;

	} else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else if (cs->mstate != MS_LOCKED) {

		dev_warn(cs->dev, "can't write to unlocked device\n");

		retval = -EBUSY;

	} else if (!cs->connected) {

		gig_dbg(DEBUG_ANY, "can't write to unplugged device");

		retval = -EBUSY; //FIXME

	} else

		retval = cs->ops->chars_in_buffer(cs);
@@ -456,7 +454,9 @@ static void if_throttle(struct tty_struct *tty) 


	mutex_lock(&cs->mutex);



	if (!cs->open_count)

	if (!cs->connected)

		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */

	else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else {

		//FIXME
@@ -479,7 +479,9 @@ static void if_unthrottle(struct tty_struct *tty) 


	mutex_lock(&cs->mutex);



	if (!cs->open_count)

	if (!cs->connected)

		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */

	else if (!cs->open_count)

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	else {

		//FIXME
@@ -506,13 +508,13 @@ static void if_set_termios(struct tty_struct *tty, struct ktermios *old) 


	mutex_lock(&cs->mutex);



	if (!cs->open_count) {

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

	if (!cs->connected) {

		gig_dbg(DEBUG_IF, "not connected");

		goto out;

	}



	if (!cs->connected) {

		gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");

	if (!cs->open_count) {

		dev_warn(cs->dev, "%s: device not opened\n", __func__);

		goto out;

	}

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