From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15F1AC10F14 for ; Thu, 3 Oct 2019 15:57:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E039F21848 for ; Thu, 3 Oct 2019 15:57:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570118246; bh=cuZo9s602fDcrRD5mupxhsazaMcvhkTI6YHA7sdWTV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HrfvVCO6n5uwhhJQdtzlFax7PT77dVqHDrIvAmvGHIyLG+cUJpiAiKl3ROQ5Bfw/G gB2Ol2woT5HQmj533vxViHy217WrZX9Ly1SgBvi7R99tuYFRfi6DE2HBG/P89rXwnG p2T7UyiZd3D9ih382ilpMQDoO/QnG7mkyYacKKF4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730942AbfJCP5Z (ORCPT ); Thu, 3 Oct 2019 11:57:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:39682 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729191AbfJCP5T (ORCPT ); Thu, 3 Oct 2019 11:57:19 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 826C1207FF; Thu, 3 Oct 2019 15:57:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570118238; bh=cuZo9s602fDcrRD5mupxhsazaMcvhkTI6YHA7sdWTV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0LsSV2rAHKXgqr/dHPyTKM3DxLhGjnoA+O0IYTRnNxfX9zTCl8qP0ONN53NRcV/it 2rV62sRMFj0NqwIdpiUXCNc32K4F3SzHsciGK/d2Q3scTagLZ4uE2m++c7meVDoYlJ wc8pbx01IXTwE1SMmhzJm/e4WOJi39gpbEj3hwNs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Luke Nowakowski-Krijger , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , syzbot+aac8d0d7205f112045d2@syzkaller.appspotmail.com Subject: [PATCH 4.4 38/99] media: hdpvr: Add device num check and handling Date: Thu, 3 Oct 2019 17:53:01 +0200 Message-Id: <20191003154313.517231276@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154252.297991283@linuxfoundation.org> References: <20191003154252.297991283@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Luke Nowakowski-Krijger [ Upstream commit d4a6a9537bc32811486282206ecfb7c53754b74d ] Add hdpvr device num check and error handling We need to increment the device count atomically before we checkout a device to make sure that we do not reach the max count, otherwise we get out-of-bounds errors as reported by syzbot. Reported-and-tested-by: syzbot+aac8d0d7205f112045d2@syzkaller.appspotmail.com Signed-off-by: Luke Nowakowski-Krijger Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/usb/hdpvr/hdpvr-core.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/media/usb/hdpvr/hdpvr-core.c b/drivers/media/usb/hdpvr/hdpvr-core.c index 08f0ca7aa012e..924517b09fc9f 100644 --- a/drivers/media/usb/hdpvr/hdpvr-core.c +++ b/drivers/media/usb/hdpvr/hdpvr-core.c @@ -278,6 +278,7 @@ static int hdpvr_probe(struct usb_interface *interface, #endif size_t buffer_size; int i; + int dev_num; int retval = -ENOMEM; /* allocate memory for our device state and initialize it */ @@ -386,8 +387,17 @@ static int hdpvr_probe(struct usb_interface *interface, } #endif + dev_num = atomic_inc_return(&dev_nr); + if (dev_num >= HDPVR_MAX) { + v4l2_err(&dev->v4l2_dev, + "max device number reached, device register failed\n"); + atomic_dec(&dev_nr); + retval = -ENODEV; + goto reg_fail; + } + retval = hdpvr_register_videodev(dev, &interface->dev, - video_nr[atomic_inc_return(&dev_nr)]); + video_nr[dev_num]); if (retval < 0) { v4l2_err(&dev->v4l2_dev, "registering videodev failed\n"); goto reg_fail; -- 2.20.1