1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 71a9409c8d7e..eb26754b2e5d 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1068,6 +1068,8 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
 	/* We want to wait for the line discipline to sort out in this
 	   situation */
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return hung_up_tty_read(file, buf, count, ppos);
 	if (ld->ops->read)
 		i = ld->ops->read(tty, file, buf, count);
 	else
@@ -1242,6 +1244,8 @@ static ssize_t tty_write(struct file *file, const char __user *buf,
 	if (tty->ops->write_room == NULL)
 		tty_err(tty, "missing write_room method\n");
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return hung_up_tty_write(file, buf, count, ppos);
 	if (!ld->ops->write)
 		ret = -EIO;
 	else
@@ -2201,6 +2205,8 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait)
 		return 0;
 
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return hung_up_tty_poll(filp, wait);
 	if (ld->ops->poll)
 		ret = ld->ops->poll(tty, filp, wait);
 	tty_ldisc_deref(ld);
@@ -2290,6 +2296,8 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
 		return -EFAULT;
 	tty_audit_tiocsti(tty, ch);
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return -EIO;
 	ld->ops->receive_buf(tty, &ch, &mbz, 1);
 	tty_ldisc_deref(ld);
 	return 0;
@@ -2682,6 +2690,8 @@ static int tiocgetd(struct tty_struct *tty, int __user *p)
 	int ret;
 
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return -EIO;
 	ret = put_user(ld->ops->num, p);
 	tty_ldisc_deref(ld);
 	return ret;
@@ -2979,6 +2989,8 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 			return retval;
 	}
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return hung_up_tty_ioctl(file, cmd, arg);
 	retval = -EINVAL;
 	if (ld->ops->ioctl) {
 		retval = ld->ops->ioctl(tty, file, cmd, arg);
@@ -3007,6 +3019,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
 	}
 
 	ld = tty_ldisc_ref_wait(tty);
+	if (!ld)
+		return hung_up_tty_compat_ioctl(file, cmd, arg);
 	if (ld->ops->compat_ioctl)
 		retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
 	else