Merge tag 'tty-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/gregkh/tty

Pull tty fixes from Greg KH:
 "Here are three small tty_io bugfixes for reported issues that Eric has
  resolved for 5.6-rc7

  All of these have been in linux-next with no reported issues"

* tag 'tty-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: fix compat TIOCGSERIAL checking wrong function ptr
  tty: fix compat TIOCGSERIAL leaking uninitialized memory
  tty: drop outdated comments about release_tty() locking

drivers/tty/tty_io.c

@@ -1589,9 +1589,7 @@ void tty_kclose(struct tty_struct *tty)
 	tty_debug_hangup(tty, "freeing structure\n");
 	/*
 	 * The release_tty function takes care of the details of clearing
-	 * the slots and preserving the termios structure. The tty_unlock_pair
-	 * should be safe as we keep a kref while the tty is locked (so the
-	 * unlock never unlocks a freed tty).
+	 * the slots and preserving the termios structure.
 	 */
 	mutex_lock(&tty_mutex);
 	tty_port_set_kopened(tty->port, 0);
@@ -1621,9 +1619,7 @@ void tty_release_struct(struct tty_struct *tty, int idx)
 	tty_debug_hangup(tty, "freeing structure\n");
 	/*
 	 * The release_tty function takes care of the details of clearing
-	 * the slots and preserving the termios structure. The tty_unlock_pair
-	 * should be safe as we keep a kref while the tty is locked (so the
-	 * unlock never unlocks a freed tty).
+	 * the slots and preserving the termios structure.
 	 */
 	mutex_lock(&tty_mutex);
 	release_tty(tty, idx);
@@ -2734,9 +2730,11 @@ static int compat_tty_tiocgserial(struct tty_struct *tty,
 	struct serial_struct32 v32;
 	struct serial_struct v;
 	int err;
-	memset(&v, 0, sizeof(struct serial_struct));
 
-	if (!tty->ops->set_serial)
+	memset(&v, 0, sizeof(v));
+	memset(&v32, 0, sizeof(v32));
+
+	if (!tty->ops->get_serial)
 		return -ENOTTY;
 	err = tty->ops->get_serial(tty, &v);
 	if (!err) {