From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755225AbdBOXXK (ORCPT ); Wed, 15 Feb 2017 18:23:10 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53843 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755099AbdBOXXF (ORCPT ); Wed, 15 Feb 2017 18:23:05 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "David Rientjes" , "Jiri Slaby" , "Greg Kroah-Hartman" , "One Thousand Gnomes" , "Dmitry Vyukov" , "Peter Hurley" , syzkaller@googlegroups.com Date: Wed, 15 Feb 2017 22:41:40 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 171/306] tty: limit terminal size to 4M chars In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.40-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Vyukov commit 32b2921e6a7461fe63b71217067a6cf4bddb132f upstream. Size of kmalloc() in vc_do_resize() is controlled by user. Too large kmalloc() size triggers WARNING message on console. Put a reasonable upper bound on terminal size to prevent WARNINGs. Signed-off-by: Dmitry Vyukov CC: David Rientjes Cc: One Thousand Gnomes Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Peter Hurley Cc: linux-kernel@vger.kernel.org Cc: syzkaller@googlegroups.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/tty/vt/vt.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -863,6 +863,8 @@ static int vc_do_resize(struct tty_struc if (new_cols == vc->vc_cols && new_rows == vc->vc_rows) return 0; + if (new_screen_size > (4 << 20)) + return -EINVAL; newscreen = kmalloc(new_screen_size, GFP_USER); if (!newscreen) return -ENOMEM;