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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 E187DC3A5A2 for ; Sun, 22 Sep 2019 19:04:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B30DA2070C for ; Sun, 22 Sep 2019 19:04:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569179091; bh=cuZo9s602fDcrRD5mupxhsazaMcvhkTI6YHA7sdWTV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YrVaZ8S/jp/WYJ3PwZx2ME8HJnF4GOZnZkBW//X00fp/VnxaBsddhyD8CkwLi87ab 31DKs+sam+sRiN1YfYCi2Rw5yJfezJE6c+r87PiwSaN71OQAT+4EZec++WNGKSGXqT PssU7ppnhZWhH78gCUtN5rKiQ/182bvtY2PtP3TA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729895AbfIVTEp (ORCPT ); Sun, 22 Sep 2019 15:04:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:37296 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725820AbfIVTBM (ORCPT ); Sun, 22 Sep 2019 15:01:12 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 04BAE214D9; Sun, 22 Sep 2019 19:01:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569178871; bh=cuZo9s602fDcrRD5mupxhsazaMcvhkTI6YHA7sdWTV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1w4N9ctZPXmo4J7WgJwqEVW73Da7az6l2rGD9eTJQOCcfQdDHh0SrzHgBM56cIP5O IB+Qd9NXlure/DvSxsoZqLDgbYCY9VhhX2jZVQ6edY8COXRPd9lNUD2VwRNzDOYhdC NxnNGNQgCYHeFVG54wOhF95zLEHKrv4ItgQPHEYI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Luke Nowakowski-Krijger , syzbot+aac8d0d7205f112045d2@syzkaller.appspotmail.com, Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 06/44] media: hdpvr: Add device num check and handling Date: Sun, 22 Sep 2019 15:00:24 -0400 Message-Id: <20190922190103.4906-6-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190922190103.4906-1-sashal@kernel.org> References: <20190922190103.4906-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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