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=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 BC621C2D0CE for ; Sun, 29 Dec 2019 17:39:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97C45207FD for ; Sun, 29 Dec 2019 17:39:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577641167; bh=QiEcSKWtt9/YX+Rd2TW93R6G0pJTiBxnRk1De19FmmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iT0wiGSc8o7Mw7l5TgCE6EnUamWAhr8VCZEUAAYgli2XdGq6Uzxwa4wzpH+yIba7v 8YVhjbR6zxRIBGO1i2KBwNfq2EVswZmP2jAVBmh5PxChhdEuMAGyfPSpLF0CBktTG6 MhJDQKGEUEHt5ygSjv4vQggs0earI7b+fzq7YQTM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729718AbfL2RjT (ORCPT ); Sun, 29 Dec 2019 12:39:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:34880 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728631AbfL2RdT (ORCPT ); Sun, 29 Dec 2019 12:33:19 -0500 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 3F35C24125; Sun, 29 Dec 2019 17:33:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577640798; bh=QiEcSKWtt9/YX+Rd2TW93R6G0pJTiBxnRk1De19FmmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BblYJVIaJ1RDIL+ind1Gzdz5k0L1R4TfAU+yI9QbrNuc8wna/3dFawkIsuzhCZz0q FbiKzSVoFLdbnHHmFeChUwmgOGaRVWFy5iKxqNMdHekSvJxCIERuCRQKdgQCF7f/ZR zVe+w+QyOAGIoFtZ2RvGH7E7hnFRGyC7PmFP8Ics= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mike Isely , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.19 144/219] media: pvrusb2: Fix oops on tear-down when radio support is not present Date: Sun, 29 Dec 2019 18:19:06 +0100 Message-Id: <20191229162530.188135670@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229162508.458551679@linuxfoundation.org> References: <20191229162508.458551679@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mike Isely [ Upstream commit 7f404ae9cf2a285f73b3c18ab9303d54b7a3d8e1 ] In some device configurations there's no radio or radio support in the driver. That's OK, as the driver sets itself up accordingly. However on tear-down in these caes it's still trying to tear down radio related context when there isn't anything there, leading to dereferences through a null pointer and chaos follows. How this bug survived unfixed for 11 years in the pvrusb2 driver is a mystery to me. [hverkuil: fix two checkpatch warnings] Signed-off-by: Mike Isely Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/usb/pvrusb2/pvrusb2-v4l2.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c index e53a80b589a1..04d334152eae 100644 --- a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c +++ b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c @@ -916,8 +916,12 @@ static void pvr2_v4l2_internal_check(struct pvr2_channel *chp) pvr2_v4l2_dev_disassociate_parent(vp->dev_video); pvr2_v4l2_dev_disassociate_parent(vp->dev_radio); if (!list_empty(&vp->dev_video->devbase.fh_list) || - !list_empty(&vp->dev_radio->devbase.fh_list)) + (vp->dev_radio && + !list_empty(&vp->dev_radio->devbase.fh_list))) { + pvr2_trace(PVR2_TRACE_STRUCT, + "pvr2_v4l2 internal_check exit-empty id=%p", vp); return; + } pvr2_v4l2_destroy_no_lock(vp); } @@ -953,7 +957,8 @@ static int pvr2_v4l2_release(struct file *file) kfree(fhp); if (vp->channel.mc_head->disconnect_flag && list_empty(&vp->dev_video->devbase.fh_list) && - list_empty(&vp->dev_radio->devbase.fh_list)) { + (!vp->dev_radio || + list_empty(&vp->dev_radio->devbase.fh_list))) { pvr2_v4l2_destroy_no_lock(vp); } return 0; -- 2.20.1