From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755960AbbILXWU (ORCPT ); Sat, 12 Sep 2015 19:22:20 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:9261 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755313AbbILXM0 (ORCPT ); Sat, 12 Sep 2015 19:12:26 -0400 Message-Id: <20150912225608.249916338@1wt.eu> User-Agent: quilt/0.63-1 Date: Sun, 13 Sep 2015 00:56:45 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mauro Carvalho Chehab , Ben Hutchings , Willy Tarreau Subject: [PATCH 2.6.32 39/62] cx24116: fix a buffer overflow when checking userspace params MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 In-Reply-To: <08d3b586eb2e764308c3de9ee398a17c@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit 1fa2337a315a2448c5434f41e00d56b01a22283c upstream. The maximum size for a DiSEqC command is 6, according to the userspace API. However, the code allows to write up much more values: drivers/media/dvb-frontends/cx24116.c:983 cx24116_send_diseqc_msg() error: buffer overflow 'd->msg' 6 <= 23 Signed-off-by: Mauro Carvalho Chehab [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings (cherry picked from commit 729c8c5e3700410e3436573abfa5b68e8d3c89d6) Signed-off-by: Willy Tarreau --- drivers/media/dvb/frontends/cx24116.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/media/dvb/frontends/cx24116.c b/drivers/media/dvb/frontends/cx24116.c index 2410d8b..b7d4847 100644 --- a/drivers/media/dvb/frontends/cx24116.c +++ b/drivers/media/dvb/frontends/cx24116.c @@ -950,6 +950,10 @@ static int cx24116_send_diseqc_msg(struct dvb_frontend *fe, struct cx24116_state *state = fe->demodulator_priv; int i, ret; + /* Validate length */ + if (d->msg_len > sizeof(d->msg)) + return -EINVAL; + /* Dump DiSEqC message */ if (debug) { printk(KERN_INFO "cx24116: %s(", __func__); @@ -961,10 +965,6 @@ static int cx24116_send_diseqc_msg(struct dvb_frontend *fe, printk(") toneburst=%d\n", toneburst); } - /* Validate length */ - if (d->msg_len > (CX24116_ARGLEN - CX24116_DISEQC_MSGOFS)) - return -EINVAL; - /* DiSEqC message */ for (i = 0; i < d->msg_len; i++) state->dsec_cmd.args[CX24116_DISEQC_MSGOFS + i] = d->msg[i]; -- 1.7.12.2.21.g234cd45.dirty