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=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 29671C43603 for ; Tue, 10 Dec 2019 21:20:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1EE820828 for ; Tue, 10 Dec 2019 21:20:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576012822; bh=k7/LvRIg+FVurNHsLIAF9XCyp1knTfLcFUKzl/naCUw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EW9Gvmp/2kdOVG87QC4GDaETENFV0tpaCZGPhUyszR6dnI3WNWDDXoqflc5RNRT0K 6F9DzW1h9K5qQlaotY4aGxn7Awem1ctCCTGTIUu2C2UbxQeF9zIEAaeIXKsyEkqUj0 IZ1lbNUM2uw5xjTm4VwK/xM7OvqdUiVxapAYIiyY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728523AbfLJVMK (ORCPT ); Tue, 10 Dec 2019 16:12:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:35276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728883AbfLJVL7 (ORCPT ); Tue, 10 Dec 2019 16:11:59 -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 D3CAC24697; Tue, 10 Dec 2019 21:11:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576012318; bh=k7/LvRIg+FVurNHsLIAF9XCyp1knTfLcFUKzl/naCUw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UQw/wknF5eI4tOnh5/N+b0fQz6zDIJ4bkJAcq25ssWJweYRZmCF9qOlJomcqWH5s/ QEtKBlA4Au38torxja+IhfaZVpxhfAlnlZ8AgfgC11VgPZPld0JXBue6hkZajz+tgJ Dy+sIrUOsZ79FCF9yEIc/+eDkMEImx6NWk9rB7Zo= 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 5.4 252/350] media: pvrusb2: Fix oops on tear-down when radio support is not present Date: Tue, 10 Dec 2019 16:05:57 -0500 Message-Id: <20191210210735.9077-213-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210210735.9077-1-sashal@kernel.org> References: <20191210210735.9077-1-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 a34717eba409b..eaa08c7999d4f 100644 --- a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c +++ b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c @@ -898,8 +898,12 @@ 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); } @@ -935,7 +939,8 @@ 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