From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933538AbeE1QJV (ORCPT ); Mon, 28 May 2018 12:09:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:33944 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965568AbeE1KOD (ORCPT ); Mon, 28 May 2018 06:14:03 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 3.18 174/185] media: cx25821: prevent out-of-bounds read on array card Date: Mon, 28 May 2018 12:03:35 +0200 Message-Id: <20180528100114.399836453@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180528100050.700971285@linuxfoundation.org> References: <20180528100050.700971285@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Colin Ian King [ Upstream commit 67300abdbe9f1717532aaf4e037222762716d0f6 ] Currently an out of range dev->nr is detected by just reporting the issue and later on an out-of-bounds read on array card occurs because of this. Fix this by checking the upper range of dev->nr with the size of array card (removes the hard coded size), move this check earlier and also exit with the error -ENOSYS to avoid the later out-of-bounds array read. Detected by CoverityScan, CID#711191 ("Out-of-bounds-read") Fixes: commit 02b20b0b4cde ("V4L/DVB (12730): Add conexant cx25821 driver") Signed-off-by: Colin Ian King Signed-off-by: Hans Verkuil [hans.verkuil@cisco.com: %ld -> %zd] Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/media/pci/cx25821/cx25821-core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/media/pci/cx25821/cx25821-core.c +++ b/drivers/media/pci/cx25821/cx25821-core.c @@ -871,6 +871,10 @@ static int cx25821_dev_setup(struct cx25 dev->nr = ++cx25821_devcount; sprintf(dev->name, "cx25821[%d]", dev->nr); + if (dev->nr >= ARRAY_SIZE(card)) { + CX25821_INFO("dev->nr >= %zd", ARRAY_SIZE(card)); + return -ENODEV; + } if (dev->pci->device != 0x8210) { pr_info("%s(): Exiting. Incorrect Hardware device = 0x%02x\n", __func__, dev->pci->device); @@ -887,9 +891,6 @@ static int cx25821_dev_setup(struct cx25 dev->channels[i].sram_channels = &cx25821_sram_channels[i]; } - if (dev->nr > 1) - CX25821_INFO("dev->nr > 1!"); - /* board config */ dev->board = 1; /* card[dev->nr]; */ dev->_max_num_decoders = MAX_DECODERS;