From patchwork Sat Jun 6 16:55:22 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 30066 Received: from mail.tu-berlin.de ([130.149.7.33]) by www.linuxtv.org with esmtp (Exim 4.72) (envelope-from ) id 1Z1HO6-0003Cn-I9; Sat, 06 Jun 2015 18:56:02 +0200 X-tubIT-Incoming-IP: 209.132.180.67 Received: from vger.kernel.org ([209.132.180.67]) by mail.tu-berlin.de (exim-4.76/mailfrontend-7) with esmtp id 1Z1HO4-0003cX-1N; Sat, 06 Jun 2015 18:56:02 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752737AbbFFQzy (ORCPT + 1 other); Sat, 6 Jun 2015 12:55:54 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:19974 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751782AbbFFQzw (ORCPT ); Sat, 6 Jun 2015 12:55:52 -0400 Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id t56GtYVx007179 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sat, 6 Jun 2015 16:55:34 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserv0021.oracle.com (8.13.8/8.13.8) with ESMTP id t56GtWBg019662 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Sat, 6 Jun 2015 16:55:33 GMT Received: from abhmp0014.oracle.com (abhmp0014.oracle.com [141.146.116.20]) by userv0121.oracle.com (8.13.8/8.13.8) with ESMTP id t56GtWFT015063; Sat, 6 Jun 2015 16:55:32 GMT Received: from mwanda (/154.0.139.178) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sat, 06 Jun 2015 09:55:31 -0700 Date: Sat, 6 Jun 2015 19:55:22 +0300 From: Dan Carpenter To: Mauro Carvalho Chehab Cc: Shuah Khan , Akihiro Tsukada , Antti Palosaari , linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] [media] dvb-core: prevent some corruption the legacy ioctl Message-ID: <20150606165521.GB28331@mwanda> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-PMX-Version: 6.0.0.2142326, Antispam-Engine: 2.7.2.2107409, Antispam-Data: 2015.6.6.164216 X-PMX-Spam: Gauge=IIIIIIIII, Probability=9%, Report=' MULTIPLE_RCPTS 0.1, HTML_00_01 0.05, HTML_00_10 0.05, MSGID_ADDED_BY_MTA 0.05, BODYTEXTP_SIZE_3000_LESS 0, BODY_SIZE_1100_1199 0, BODY_SIZE_2000_LESS 0, BODY_SIZE_5000_LESS 0, BODY_SIZE_7000_LESS 0, INVALID_MSGID_NO_FQDN 0, URI_ENDS_IN_HTML 0, __ANY_URI 0, __CD 0, __CP_URI_IN_BODY 0, __CT 0, __CT_TEXT_PLAIN 0, __DATE_TZ_RU 0, __HAS_FROM 0, __HAS_MSGID 0, __HAS_X_MAILING_LIST 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __MULTIPLE_RCPTS_CC_X2 0, __SANE_MSGID 0, __SUBJ_ALPHA_END 0, __TO_MALFORMED_2 0, __URI_NO_WWW 0, __URI_NS , __USER_AGENT 0' Quite a few of the ->diseqc_send_master_cmd() implementations don't check cmd->msg_len so it can lead to memory corruption. Signed-off-by: Dan Carpenter --- I don't think it ever makes sense for ->msg_len to be longer than ->msg but I am a newbie to this code. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c index a894d4c..aa6b48f 100644 --- a/drivers/media/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb-core/dvb_frontend.c @@ -2403,7 +2403,13 @@ static int dvb_frontend_ioctl_legacy(struct file *file, case FE_DISEQC_SEND_MASTER_CMD: if (fe->ops.diseqc_send_master_cmd) { - err = fe->ops.diseqc_send_master_cmd(fe, (struct dvb_diseqc_master_cmd*) parg); + struct dvb_diseqc_master_cmd *cmd = parg; + + if (cmd->msg_len > sizeof(cmd->msg)) { + err = -EINVAL; + break; + } + err = fe->ops.diseqc_send_master_cmd(fe, cmd); fepriv->state = FESTATE_DISEQC; fepriv->status = 0; }