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 73013C636CE for ; Mon, 19 Jul 2021 15:11:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6185060551 for ; Mon, 19 Jul 2021 15:11:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244220AbhGSO32 (ORCPT ); Mon, 19 Jul 2021 10:29:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:37344 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244151AbhGSOYx (ORCPT ); Mon, 19 Jul 2021 10:24:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8CBD36113E; Mon, 19 Jul 2021 15:05:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626707121; bh=dHX1inVFLxX/mAZfDaFUbZKuIuq3XDpHsC/pHKJDIA0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ik5mKspZNrAEsUNQ3SoDEqhP+afohlln7HEQmCitrYDbkYY2d0PgtIMouequ7VHD/ Nt/Wzy16fI6HCJ/ZK8YO8ksKS+33ltRENSfhbz3MkWgh1G0l0uoGXd7YrwDa3LeHAs aOSTq3LTcen3/reftt/Cn5W+JANdblZmhZBfosMk= 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 4.9 038/245] media: v4l2-core: Avoid the dangling pointer in v4l2_fh_release Date: Mon, 19 Jul 2021 16:49:40 +0200 Message-Id: <20210719144941.623497768@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144940.288257948@linuxfoundation.org> References: <20210719144940.288257948@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 0c5e69070586..d44b289205b4 100644 --- a/drivers/media/v4l2-core/v4l2-fh.c +++ b/drivers/media/v4l2-core/v4l2-fh.c @@ -109,6 +109,7 @@ 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