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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 26874C433ED for ; Mon, 3 May 2021 17:07:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC45B6100A for ; Mon, 3 May 2021 17:07:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236318AbhECRG0 (ORCPT ); Mon, 3 May 2021 13:06:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:43040 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235298AbhECQ4K (ORCPT ); Mon, 3 May 2021 12:56:10 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3F11861962; Mon, 3 May 2021 16:43:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620060199; bh=+fXdL/7vNmQLpNMjy3WhSp3t8ZHg4Y0vuI8idMut46Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OEqXT15jc5GsmHwEZ1mgnT7ZS9/rmMMdlnwr6jz61llt+s1qnS2O/d0fDAH2Goz6Z Y1kmDPLCdSfSqIVsAv6pkCMQV71+lVnZrHdcHAwuZe/DMjvnescwKuCtTNMpE40sI1 hey0DBaM8sQLqZoW90IJ7vNOcHfRSakDJCazaHj51WKwZCggBk6UhhWE9pDBh/RIGr b3Sk4EzgT8VSJMWyFa6hmFSoNS0pj9dVYNhyGutZan/EGgtnx0L1BUqQvk2KP/jLsy UwnrolqEEG2bXa6dzWZd+P/uKFsMwa8/sryrptXop1zhsqE/AZJ82ICic18UT914QV 5R7OacCEfY55w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yang Yingliang , Hulk Robot , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 18/24] media: i2c: adv7842: fix possible use-after-free in adv7842_remove() Date: Mon, 3 May 2021 12:42:46 -0400 Message-Id: <20210503164252.2854487-18-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210503164252.2854487-1-sashal@kernel.org> References: <20210503164252.2854487-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 cf3b42c9417e..d7af4fbcb84b 100644 --- a/drivers/media/i2c/adv7842.c +++ b/drivers/media/i2c/adv7842.c @@ -3598,7 +3598,7 @@ 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