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 BDFF2C6377C for ; Thu, 15 Jul 2021 19:23:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94EF2613E4 for ; Thu, 15 Jul 2021 19:23:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344047AbhGOTZB (ORCPT ); Thu, 15 Jul 2021 15:25:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:45628 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242669AbhGOTIM (ORCPT ); Thu, 15 Jul 2021 15:08:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8BA11613DB; Thu, 15 Jul 2021 19:04:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626375846; bh=9upz0cKdc/qYU4JjyOzTGWrs6l3cCYP97s9qfpHPtkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vKQG9fTcAxv/kUh//076ZFrj4DMlhYpIUeUbO0s/OdQzel4pmW+5TfEwmMMRdgLiA 4TnzM3wzeLNuTwBME5zIDh9n9ZE09FAe4hdPCf+DznRutbeVyapb5fNt8EPFM7GOVI sS9CuUxcxJriICdQIlqR/aNFOFrf3Y/QMVlQBA9g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hulk Robot , Zou Wei , "David S. Miller" , Sasha Levin Subject: [PATCH 5.13 019/266] mISDN: fix possible use-after-free in HFC_cleanup() Date: Thu, 15 Jul 2021 20:36:14 +0200 Message-Id: <20210715182617.280276704@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182613.933608881@linuxfoundation.org> References: <20210715182613.933608881@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: Zou Wei [ Upstream commit 009fc857c5f6fda81f2f7dd851b2d54193a8e733 ] This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself. Reported-by: Hulk Robot Signed-off-by: Zou Wei Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/isdn/hardware/mISDN/hfcpci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/isdn/hardware/mISDN/hfcpci.c b/drivers/isdn/hardware/mISDN/hfcpci.c index 56bd2e9db6ed..e501cb03f211 100644 --- a/drivers/isdn/hardware/mISDN/hfcpci.c +++ b/drivers/isdn/hardware/mISDN/hfcpci.c @@ -2342,7 +2342,7 @@ static void __exit HFC_cleanup(void) { if (timer_pending(&hfc_tl)) - del_timer(&hfc_tl); + del_timer_sync(&hfc_tl); pci_unregister_driver(&hfc_driver); } -- 2.30.2