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=-20.4 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=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 B1789C07E96 for ; Tue, 6 Jul 2021 12:11:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EDD3621B5 for ; Tue, 6 Jul 2021 12:11:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238821AbhGFMNY (ORCPT ); Tue, 6 Jul 2021 08:13:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:47550 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234370AbhGFLhB (ORCPT ); Tue, 6 Jul 2021 07:37:01 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D60FF61F28; Tue, 6 Jul 2021 11:29:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625570977; bh=zGOVYjwyMffJLWfigNL2olJxhT7aPhNmZaFHOVgs7cA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EEu1l0kMfTWOn5gD1BHaEHrOQgiHzVApKcu24u2ulmpLrbQUhAvIWoOQz1O9OF6KY tnFtMLOR6u/545I9qJGq0RNiVOo5MCxWnwj6/AQfO4bpu656wSLROOHC/k1XqQuLSX 6iJJlD18rK6IXQXYhOYPnuDbadlaTt4GIz5IY5U5sSnm9WYkoICYCSvN+ZQ8Xql6Dh dxE8XVmzGMD1OIrWMX/dSn4objInjzIFCHKFjyK44d3jsN87y9sFqRyVRDEscdZffi jTKRDoblvbNDHaW13F69gXb4w1D5b6vX5Zie11wojkUfoc/eg/X7bnlJ7Aev1geJke 6E1EqPHI7vk/A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zou Wei , Hulk Robot , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 04/31] mISDN: fix possible use-after-free in HFC_cleanup() Date: Tue, 6 Jul 2021 07:29:04 -0400 Message-Id: <20210706112931.2066397-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210706112931.2066397-1-sashal@kernel.org> References: <20210706112931.2066397-1-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: 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 ff48da61c94c..89cf1d695a01 100644 --- a/drivers/isdn/hardware/mISDN/hfcpci.c +++ b/drivers/isdn/hardware/mISDN/hfcpci.c @@ -2352,7 +2352,7 @@ 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