From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161768AbdEWVAL (ORCPT ); Tue, 23 May 2017 17:00:11 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:55926 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161738AbdEWVAD (ORCPT ); Tue, 23 May 2017 17:00:03 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sri Deevi , Johan Hovold , Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.4 077/103] [media] cx231xx-audio: fix NULL-deref at probe Date: Tue, 23 May 2017 22:09:43 +0200 Message-Id: <20170523200902.883688307@linuxfoundation.org> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20170523200856.903752266@linuxfoundation.org> References: <20170523200856.903752266@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 65f921647f4c89a2068478c89691f39b309b58f7 upstream. Make sure to check the number of endpoints to avoid dereferencing a NULL-pointer or accessing memory beyond the endpoint array should a malicious device lack the expected endpoints. Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Cc: Sri Deevi Signed-off-by: Johan Hovold Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/usb/cx231xx/cx231xx-audio.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) --- a/drivers/media/usb/cx231xx/cx231xx-audio.c +++ b/drivers/media/usb/cx231xx/cx231xx-audio.c @@ -698,6 +698,11 @@ static int cx231xx_audio_init(struct cx2 hs_config_info[0].interface_info. audio_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) { + err = -ENODEV; + goto err_free_card; + } + adev->end_point_addr = uif->altsetting[0].endpoint[isoc_pipe].desc. bEndpointAddress; @@ -713,8 +718,14 @@ static int cx231xx_audio_init(struct cx2 } for (i = 0; i < adev->num_alt; i++) { - u16 tmp = - le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc. + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) { + err = -ENODEV; + goto err_free_pkt_size; + } + + tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc. wMaxPacketSize); adev->alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1); @@ -725,6 +736,8 @@ static int cx231xx_audio_init(struct cx2 return 0; +err_free_pkt_size: + kfree(adev->alt_max_pkt_size); err_free_card: snd_card_free(card);