From patchwork Thu May 20 09:17:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 444539 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=-19.1 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=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 B7693C433B4 for ; Thu, 20 May 2021 09:40:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DB896100A for ; Thu, 20 May 2021 09:40:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232558AbhETJmO (ORCPT ); Thu, 20 May 2021 05:42:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:41238 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232919AbhETJkQ (ORCPT ); Thu, 20 May 2021 05:40:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EFDA360FDB; Thu, 20 May 2021 09:31:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621503093; bh=evni02BbwAdeZIzay0TcfA75MDlrzK9isldoS+5pYSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fl8+RJfIE8JpNfoaGQ/X893X8dZ7gCF+ZUjk1CJiAdPohcMLOU5rocdqTu5/PWLRO s0o1PIvyYY4NmI5QYZgJIihKRakCETSNFcliseB5kUUTvTuXnoG8GF6TsAbcKZecVP w2yfTRkF2xaw5tAqOUaUqhHrhz/fIpeOAUfC5G68= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hulk Robot , Yang Yingliang , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.19 064/425] media: i2c: adv7842: fix possible use-after-free in adv7842_remove() Date: Thu, 20 May 2021 11:17:13 +0200 Message-Id: <20210520092133.551140389@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092131.308959589@linuxfoundation.org> References: <20210520092131.308959589@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yang Yingliang [ Upstream commit 4a15275b6a18597079f18241c87511406575179a ] This driver's remove path calls cancel_delayed_work(). However, that function does not wait until the work function finishes. This means that the callback function may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling cancel_delayed_work_sync(), which ensures that the work is properly cancelled, no longer running, and unable to re-schedule itself. Reported-by: Hulk Robot Signed-off-by: Yang Yingliang Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/i2c/adv7842.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/i2c/adv7842.c b/drivers/media/i2c/adv7842.c index 58662ba92d4f..d0ed20652ddb 100644 --- a/drivers/media/i2c/adv7842.c +++ b/drivers/media/i2c/adv7842.c @@ -3585,7 +3585,7 @@ static int adv7842_remove(struct i2c_client *client) struct adv7842_state *state = to_state(sd); adv7842_irq_enable(sd, false); - cancel_delayed_work(&state->delayed_work_enable_hotplug); + cancel_delayed_work_sync(&state->delayed_work_enable_hotplug); v4l2_device_unregister_subdev(sd); media_entity_cleanup(&sd->entity); adv7842_unregister_clients(sd);