From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753997AbdBEUCy (ORCPT + 2 others); Sun, 5 Feb 2017 15:02:54 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:28024 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753119AbdBETZM (ORCPT ); Sun, 5 Feb 2017 14:25:12 -0500 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Dmitry Vyukov , David Rientjes , One Thousand Gnomes , Greg Kroah-Hartman , Jiri Slaby , Peter Hurley , syzkaller@googlegroups.com, Willy Tarreau Subject: [PATCH 3.10 213/319] tty: limit terminal size to 4M chars Date: Sun, 5 Feb 2017 20:20:35 +0100 Message-Id: <1486322541-8206-114-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1486322541-8206-1-git-send-email-w@1wt.eu> References: <1486322541-8206-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 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: Willy Tarreau --- drivers/tty/vt/vt.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 6dff194..ee51acd 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -863,6 +863,8 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc, 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; -- 2.8.0.rc2.1.gbe9624a