From 5c3647b8a30d1ba3d2bb2b43bbb7b867dbcf28d6 Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Thu, 24 Oct 2019 21:03:49 +0200
Subject: [PATCH] TTY: MasterPTY should fail to ioctl() if slave is gone

Just fail with EIO in that case.
---
 Kernel/TTY/MasterPTY.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Kernel/TTY/MasterPTY.cpp b/Kernel/TTY/MasterPTY.cpp
index cace566a99..efd29a7f27 100644
--- a/Kernel/TTY/MasterPTY.cpp
+++ b/Kernel/TTY/MasterPTY.cpp
@@ -98,6 +98,8 @@ void MasterPTY::close()
 
 int MasterPTY::ioctl(FileDescription& description, unsigned request, unsigned arg)
 {
+    if (!m_slave)
+        return -EIO;
     if (request == TIOCSWINSZ || request == TIOCGPGRP)
         return m_slave->ioctl(description, request, arg);
     return -EINVAL;