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,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 E5778C433F5 for ; Fri, 17 Sep 2021 02:36:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2A9761108 for ; Fri, 17 Sep 2021 02:36:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243459AbhIQChu (ORCPT ); Thu, 16 Sep 2021 22:37:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:34322 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243433AbhIQCgb (ORCPT ); Thu, 16 Sep 2021 22:36:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 39D7061139; Fri, 17 Sep 2021 02:35:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631846110; bh=c3XCtVyOOmSN8//YWlQxWHyl3bALKGKJUAe/8BgASdE=; h=From:To:Cc:Subject:Date:From; b=WW56fg2DEIBXn6QuZKh5v44CDC+eBZrYk+P7TzbcmHtRKAPjrVK526CA3Vo9vRkl/ d3j8ZZoTHmzw9eIxMn765ZrH275omKrfH+kuDTfXZSIxZTNx/k0QUdsONRqUUD8E/7 nsckq/HSOwAYlRbLu2Yml9CaH4iDPRwXYv+YLT12dXaNeJEQgY6/fatXsI3My7yHXj +EUHkKZ8gZH4bt3jOpMXFClPptbscn2IBT+s3sqmB7LGiKiwIa/STu2TqG9Y4xToG5 Ki6AZ3g7boIoR2JQL7M62lJ1Rq9LB77z1x+EDqJaktihdL7YXN2rtZXtgWuz97Bmh3 vKBvx1nauHuOA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Li Jinlin , Jens Axboe , Sasha Levin , tj@kernel.org, cgroups@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH AUTOSEL 4.9] blk-throttle: fix UAF by deleteing timer in blk_throtl_exit() Date: Thu, 16 Sep 2021 22:35:08 -0400 Message-Id: <20210917023508.816980-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 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: Li Jinlin [ Upstream commit 884f0e84f1e3195b801319c8ec3d5774e9bf2710 ] The pending timer has been set up in blk_throtl_init(). However, the timer is not deleted in blk_throtl_exit(). This means that the timer handler may still be running after freeing the timer, which would result in a use-after-free. Fix by calling del_timer_sync() to delete the timer in blk_throtl_exit(). Signed-off-by: Li Jinlin Link: https://lore.kernel.org/r/20210907121242.2885564-1-lijinlin3@huawei.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-throttle.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 3a4c9a3c1427..6435dc25be0a 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1584,6 +1584,7 @@ int blk_throtl_init(struct request_queue *q) void blk_throtl_exit(struct request_queue *q) { BUG_ON(!q->td); + del_timer_sync(&q->td->service_queue.pending_timer); throtl_shutdown_wq(q); blkcg_deactivate_policy(q, &blkcg_policy_throtl); kfree(q->td); -- 2.30.2