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=-20.2 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 68998C433EF for ; Fri, 24 Sep 2021 12:49:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51B9F6135D for ; Fri, 24 Sep 2021 12:49:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344585AbhIXMut (ORCPT ); Fri, 24 Sep 2021 08:50:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:45754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343965AbhIXMtP (ORCPT ); Fri, 24 Sep 2021 08:49:15 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 02DCF61164; Fri, 24 Sep 2021 12:47:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632487662; bh=aJQe5lCArK09m0hsV83U8kMbXwdCnposyjYAP3kZq/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=weBHuNVdFHClkU84CNKd9rZ5eT5IOcx+UTjt6Kkyxsn+9NYnkgR9oBH/gfE1JtfRl hFYZr/fOnZ0hlw5+F8m5WMV3OvBykM7hnP9xjJLqrrqsBfIBIAAjP2GNbVhPKn4koH CY3wWJt6iRnxg2Uw+oJXI7G3suw4THG+C0d0lj3M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Li Jinlin , Jens Axboe , Sasha Levin Subject: [PATCH 4.14 26/27] blk-throttle: fix UAF by deleteing timer in blk_throtl_exit() Date: Fri, 24 Sep 2021 14:44:20 +0200 Message-Id: <20210924124330.053225617@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210924124329.173674820@linuxfoundation.org> References: <20210924124329.173674820@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: stable@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 a8cd7b3d9647..fcbbe2e45a2b 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -2414,6 +2414,7 @@ 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); free_percpu(q->td->latency_buckets); -- 2.33.0