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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 44DD6C6377B for ; Mon, 19 Jul 2021 14:57:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2EDD8610D2 for ; Mon, 19 Jul 2021 14:57:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241616AbhGSORE (ORCPT ); Mon, 19 Jul 2021 10:17:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:49004 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241676AbhGSOQo (ORCPT ); Mon, 19 Jul 2021 10:16:44 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B7B24610F7; Mon, 19 Jul 2021 14:57:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626706644; bh=FSyh4ATv5z5J1QHnSLtm7oz7ME9uM7NWV2nCpkUkoMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DCE4v99kvHHI5bgHYN30sV8Hp07i/7mLN6HhWpX6L77TMVKK+B9kvCA+mNzre9st3 /SWi0PEIKDdvBTT0n4JsNqFOh/ld1//0m2BvMg9oqleYwtEbeVQTScN0VLCnqKtBt2 PgKq7zH43TkSh2h3afWqigV95ifeor55wa7VB7b4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lv Yunlong , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.4 034/188] media: v4l2-core: Avoid the dangling pointer in v4l2_fh_release Date: Mon, 19 Jul 2021 16:50:18 +0200 Message-Id: <20210719144921.033366722@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144913.076563739@linuxfoundation.org> References: <20210719144913.076563739@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lv Yunlong [ Upstream commit 7dd0c9e547b6924e18712b6b51aa3cba1896ee2c ] A use after free bug caused by the dangling pointer filp->privitate_data in v4l2_fh_release. See https://lore.kernel.org/patchwork/patch/1419058/. My patch sets the dangling pointer to NULL to provide robust. Signed-off-by: Lv Yunlong Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/v4l2-core/v4l2-fh.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/media/v4l2-core/v4l2-fh.c b/drivers/media/v4l2-core/v4l2-fh.c index 1d076deb05a9..ce844ecc3340 100644 --- a/drivers/media/v4l2-core/v4l2-fh.c +++ b/drivers/media/v4l2-core/v4l2-fh.c @@ -107,6 +107,7 @@ int v4l2_fh_release(struct file *filp) v4l2_fh_del(fh); v4l2_fh_exit(fh); kfree(fh); + filp->private_data = NULL; } return 0; } -- 2.30.2