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=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 74511C11FEE for ; Tue, 6 Jul 2021 12:02:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EC0762119 for ; Tue, 6 Jul 2021 12:02:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240063AbhGFMFH (ORCPT ); Tue, 6 Jul 2021 08:05:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:47578 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237628AbhGFLgU (ORCPT ); Tue, 6 Jul 2021 07:36:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 37AAD61DCD; Tue, 6 Jul 2021 11:28:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625570934; bh=zGOVYjwyMffJLWfigNL2olJxhT7aPhNmZaFHOVgs7cA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VT023MvMIe+bxiAs30p4s1npQHaAidcagDSvQMct6pQYkWTH5cPt6GJV6/PVK1gAX Hbxjw5YfuzHpevLeeIhy9thE5Bp2OI1U+9MaxjuboKMLp/DswQsXW2zX2Ukog4xZL9 N2H/zhKhi2fWJhphgpzlTRTAoyjirg9qy7zsQsStyUl9rF4gpeaoaisEHfr405yn+K 7cMb05pddR6tLCgPm88W6W38NaVUeAki6aTH/6WFJDm2ln2p5eFSLg1pDdGOO/PYTR /UU9NyyP1LNyZTnvSfTWIy9OOpvBtteQ/c4Pf+8Ws9bMMZhpvyHwFqZ5B1GS18saGf BP0YkyMAfqjCg== 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 4.9 04/35] mISDN: fix possible use-after-free in HFC_cleanup() Date: Tue, 6 Jul 2021 07:28:16 -0400 Message-Id: <20210706112848.2066036-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210706112848.2066036-1-sashal@kernel.org> References: <20210706112848.2066036-1-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