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=-19.1 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=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 B4EBCC433ED for ; Thu, 20 May 2021 09:41:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 926E061939 for ; Thu, 20 May 2021 09:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233120AbhETJm3 (ORCPT ); Thu, 20 May 2021 05:42:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:41074 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232685AbhETJjr (ORCPT ); Thu, 20 May 2021 05:39:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 86E936142F; Thu, 20 May 2021 09:31:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621503089; bh=FioYxK1JVl1Z9iYz7eBh+7t5FbD8I6Vku1QOl4rzR48=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TsiYhktguPNa26XAv5tyOg5t5iU7NJczZiOttbJTCtHZ5tDraFjGhR2cOJMyXKjfI F0E4D915gWEBmAx8varWTGG2kROhl6btHHXmvijYPuLXMOafXKvPWy1kjlvK3tfSpi KUPhyXAP6opsvaPJnUmkrnGS4vKhgUNTxGBHb3T8= 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 4.19 062/425] media: adv7604: fix possible use-after-free in adv76xx_remove() Date: Thu, 20 May 2021 11:17:11 +0200 Message-Id: <20210520092133.476798135@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 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 fa56f5f1fe31c2050675fa63b84963ebd504a5b3 ] 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/adv7604.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c index a4b0a89c7e7e..04577d409e63 100644 --- a/drivers/media/i2c/adv7604.c +++ b/drivers/media/i2c/adv7604.c @@ -3560,7 +3560,7 @@ static int adv76xx_remove(struct i2c_client *client) io_write(sd, 0x6e, 0); io_write(sd, 0x73, 0); - cancel_delayed_work(&state->delayed_work_enable_hotplug); + cancel_delayed_work_sync(&state->delayed_work_enable_hotplug); v4l2_async_unregister_subdev(sd); media_entity_cleanup(&sd->entity); adv76xx_unregister_clients(to_state(sd)); -- 2.30.2