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,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 5E57EC00454 for ; Tue, 10 Dec 2019 21:39:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 32B54208C3 for ; Tue, 10 Dec 2019 21:39:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576013965; bh=1babmQM4+K24X+5mb2qf7Srsl8X3oOursEsQlBCqiuA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=D8vezJ+Fu8eR/uVoOQbaFBOY0kDiXwA3S+02PJvojRiNquntHD0OQ4eIRedmbEaXx CQ/2yKjvHlOgNn8Zuf0wrAD5h/cb1vDeYZ3cH0a8JIGmN0aldBAPwF0wsUkEggKP+g DLCX/LsqszV13CdWUzvRPYc/IqWvJTQKz61OCfqc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727101AbfLJVjX (ORCPT ); Tue, 10 Dec 2019 16:39:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:40492 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729742AbfLJVfA (ORCPT ); Tue, 10 Dec 2019 16:35:00 -0500 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 2630F207FF; Tue, 10 Dec 2019 21:34:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576013699; bh=1babmQM4+K24X+5mb2qf7Srsl8X3oOursEsQlBCqiuA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JEoVc1hi+TyaFdTiynZr8IDWJRXdYmNmTNrOkpUADhEsyj4TaWaWh1s9usL8r/Byk pItubQs1Qvb3u2mnGxEsahSE33VmMsGtFHGDuQ3n0VvKUowM3vZb5ra7ab85OHp96a O4Kh6W8wvwWUGCAc2Mv7uK4RIJzY83iZD/rVaJuU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mike Isely , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 129/177] media: pvrusb2: Fix oops on tear-down when radio support is not present Date: Tue, 10 Dec 2019 16:31:33 -0500 Message-Id: <20191210213221.11921-129-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210213221.11921-1-sashal@kernel.org> References: <20191210213221.11921-1-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: 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 e53a80b589a15..04d334152eae2 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