From: Eric Biggers ebiggers@google.com
commit 6e622cd8bd888c7fa3ee2b7dfb3514ab53b21570 upstream.
Commit 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start checking for the presence of the ->set_serial function pointer rather than ->get_serial. This appears to be a copy-and-paste error, since ->get_serial is the function pointer that is called as well as the pointer that is checked by the non-compat version of TIOCGSERIAL.
Fix this by checking the correct function pointer.
Fixes: 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Eric Biggers ebiggers@google.com Acked-by: Jiri Slaby jslaby@suse.cz Link: https://lore.kernel.org/r/20200224182044.234553-3-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/tty/tty_io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2738,7 +2738,7 @@ static int compat_tty_tiocgserial(struct memset(&v, 0, sizeof(v)); memset(&v32, 0, sizeof(v32));
- if (!tty->ops->set_serial) + if (!tty->ops->get_serial) return -ENOTTY; err = tty->ops->get_serial(tty, &v); if (!err) {