Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753224AbdFGXqX (ORCPT ); Wed, 7 Jun 2017 19:46:23 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:50565 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752946AbdFGXEU (ORCPT ); Wed, 7 Jun 2017 19:04:20 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Willy Tarreau , Ben Hutchings Subject: [PATCH 3.10 250/250] char: lp: fix possible integer overflow in lp_setup() Date: Thu, 8 Jun 2017 01:00:36 +0200 Message-Id: <1496876436-32402-251-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1496876436-32402-1-git-send-email-w@1wt.eu> References: <1496876436-32402-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1047 Lines: 32 commit 3e21f4af170bebf47c187c1ff8bf155583c9f3b1 upstream. The lp_setup() code doesn't apply any bounds checking when passing "lp=none", and only in this case, resulting in an overflow of the parport_nr[] array. All versions in Git history are affected. Reported-By: Roee Hay Cc: Ben Hutchings Signed-off-by: Willy Tarreau --- drivers/char/lp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/char/lp.c b/drivers/char/lp.c index 0913d79..6b61910 100644 --- a/drivers/char/lp.c +++ b/drivers/char/lp.c @@ -857,7 +857,11 @@ static int __init lp_setup (char *str) } else if (!strcmp(str, "auto")) { parport_nr[0] = LP_PARPORT_AUTO; } else if (!strcmp(str, "none")) { - parport_nr[parport_ptr++] = LP_PARPORT_NONE; + if (parport_ptr < LP_NO) + parport_nr[parport_ptr++] = LP_PARPORT_NONE; + else + printk(KERN_INFO "lp: too many ports, %s ignored.\n", + str); } else if (!strcmp(str, "reset")) { reset = 1; } -- 2.8.0.rc2.1.gbe9624a