From 8af4352278c88da800df901e80a99dccc583cf56 Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@intel.com>
Date: Thu, 2 Oct 2014 16:34:31 +0300
Subject: [PATCH] tty/vt: don't set font mappings on vc not supporting this

commit 9e326f78713a4421fe11afc2ddeac07698fac131 upstream.

We can call this function for a dummy console that doesn't support
setting the font mapping, which will result in a null ptr BUG. So check
for this case and return error for consoles w/o font mapping support.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=59321
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/tty/vt/consolemap.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c
index 2978ca596a7ff..0e75d2a765115 100644
--- a/drivers/tty/vt/consolemap.c
+++ b/drivers/tty/vt/consolemap.c
@@ -540,6 +540,12 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
 
 	/* Save original vc_unipagdir_loc in case we allocate a new one */
 	p = (struct uni_pagedir *)*vc->vc_uni_pagedir_loc;
+
+	if (!p) {
+		err = -EINVAL;
+
+		goto out_unlock;
+	}
 	if (p->readonly) {
 		console_unlock();
 		return -EIO;
@@ -633,6 +639,7 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
 		set_inverse_transl(vc, p, i); /* Update inverse translations */
 	set_inverse_trans_unicode(vc, p);
 
+out_unlock:
 	console_unlock();
 	return err;
 }