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 0CF64C43603 for ; Tue, 10 Dec 2019 22:35:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D378C2073D for ; Tue, 10 Dec 2019 22:35:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017334; bh=WQ3Li1psb4hv/QIV9QWOgQ+DgDXxIcwAt7zduwsnj0s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0HhtT9oFsS/MV07vv+t4d597MjKwgqM9kNOquHDHerx1wiIIlz8MWBkz2yvqjiMKu mVklcqMkOXBrpZuJXdPGRm2y+OxOocCnjdx5JfSduft7hwxrFJCSj0ehRxL0ueoJ3t LYQETzjAkxRWHzmEmvuGeffP8K8jNJt5vci7Qm28= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730385AbfLJWed (ORCPT ); Tue, 10 Dec 2019 17:34:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:55652 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730240AbfLJWeS (ORCPT ); Tue, 10 Dec 2019 17:34:18 -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 4D8C0208C3; Tue, 10 Dec 2019 22:34:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017258; bh=WQ3Li1psb4hv/QIV9QWOgQ+DgDXxIcwAt7zduwsnj0s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ftmJPGBPdEA92M/Cwx9VcwKaUMygs1gsAnyRcRBwAw2pjnd7PyxgsVWGDxcORnfG4 GCsQkmC+beUaqXZpcz9ijONlBtttGj6DYtRzS3rDlUdXWEzGYDBM1G9q3MfZD0DESX ggBEaCH0heaZemNAaawozvmQYwfdyHxzZVWbuPlA= 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 4.4 52/71] media: pvrusb2: Fix oops on tear-down when radio support is not present Date: Tue, 10 Dec 2019 17:32:57 -0500 Message-Id: <20191210223316.14988-52-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210223316.14988-1-sashal@kernel.org> References: <20191210223316.14988-1-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 1c5f85bf7ed4b..2d6195e9a1953 100644 --- a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c +++ b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c @@ -886,8 +886,12 @@ 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); } @@ -961,7 +965,8 @@ 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