From patchwork Thu May 20 09:20:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 444158 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 280C2C43460 for ; Thu, 20 May 2021 10:51:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D85761001 for ; Thu, 20 May 2021 10:51:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238600AbhETKwW (ORCPT ); Thu, 20 May 2021 06:52:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:48252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238820AbhETKuU (ORCPT ); Thu, 20 May 2021 06:50:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 44EEE61CC5; Thu, 20 May 2021 09:59:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621504771; bh=4z/ycUZ7/q9+pbbzp4P379DE3gn4uLBgDMv3QLkQ/dc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iwPDig/0ZhRyVpiB38lvhTG0MfnwAQqbQ+iUkO6hXLhZoT4321mP2wYZRp10DXxaZ GgCWQaC3wSC7eYi6B7Wn23SJwm+I+U2X26YkePEjTW6jmCnBAjt9sJ5t5T9jhmd9HC JqE1oWt/6vEvk+eg85z0RpSz1XAKbkKWmSJpOdwQ= 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 4.9 040/240] media: i2c: adv7511-v4l2: fix possible use-after-free in adv7511_remove() Date: Thu, 20 May 2021 11:20:32 +0200 Message-Id: <20210520092109.999724552@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092108.587553970@linuxfoundation.org> References: <20210520092108.587553970@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 2c9541720c66899adf6f3600984cf3ef151295ad ] 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/adv7511-v4l2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/i2c/adv7511-v4l2.c b/drivers/media/i2c/adv7511-v4l2.c index b87c9e7ff146..e81c4cca50c6 100644 --- a/drivers/media/i2c/adv7511-v4l2.c +++ b/drivers/media/i2c/adv7511-v4l2.c @@ -1976,7 +1976,7 @@ static int adv7511_remove(struct i2c_client *client) adv7511_set_isr(sd, false); adv7511_init_setup(sd); - cancel_delayed_work(&state->edid_handler); + cancel_delayed_work_sync(&state->edid_handler); i2c_unregister_device(state->i2c_edid); if (state->i2c_cec) i2c_unregister_device(state->i2c_cec);