From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Roee Hay , Ben Hutchings , Willy Tarreau Subject: [PATCH 3.18 03/59] char: lp: fix possible integer overflow in lp_setup() Date: Tue, 23 May 2017 22:09:31 +0200 Message-Id: <20170523200849.481925444@linuxfoundation.org> In-Reply-To: <20170523200849.241966497@linuxfoundation.org> References: <20170523200849.241966497@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Willy Tarreau 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 Signed-off-by: Greg Kroah-Hartman --- drivers/char/lp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/char/lp.c +++ b/drivers/char/lp.c @@ -859,7 +859,11 @@ 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; }