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=-19.4 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 20C02C433B4 for ; Mon, 10 May 2021 12:26:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D43A360FE3 for ; Mon, 10 May 2021 12:26:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235636AbhEJM1W (ORCPT ); Mon, 10 May 2021 08:27:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:49920 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237207AbhEJLLf (ORCPT ); Mon, 10 May 2021 07:11:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3F0C461883; Mon, 10 May 2021 11:08:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620644893; bh=kW+Kz7+iyT/blgzYJhQ6JJtZ8Tz4bngwHmfpwDRDbB8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T7Lt/xFx6nVyPmOfnyQi6CzOSeVsL7SThZ3pj5Kd8Zbpw5cGDziTtYgjgpnD5Bkvc UgAmTi00yiXZ14MUfXQ9rFMuM9qvC5mHRXNHFsXOVzEptXEXk0f+csrFBfYJey82/g 22crBTLa5GS7bclzk7zqytMtJ4MWIXxUuvMsHxUA= 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 5.12 233/384] media: i2c: adv7842: fix possible use-after-free in adv7842_remove() Date: Mon, 10 May 2021 12:20:22 +0200 Message-Id: <20210510102022.573929827@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102014.849075526@linuxfoundation.org> References: <20210510102014.849075526@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: 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 0855f648416d..f7d2b6cd3008 100644 --- a/drivers/media/i2c/adv7842.c +++ b/drivers/media/i2c/adv7842.c @@ -3586,7 +3586,7 @@ 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); -- 2.30.2