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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 91044C433E0 for ; Fri, 12 Jun 2020 09:11:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 714FA20836 for ; Fri, 12 Jun 2020 09:11:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726506AbgFLJLC (ORCPT ); Fri, 12 Jun 2020 05:11:02 -0400 Received: from nautica.notk.org ([91.121.71.147]:36412 "EHLO nautica.notk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726302AbgFLJLB (ORCPT ); Fri, 12 Jun 2020 05:11:01 -0400 Received: by nautica.notk.org (Postfix, from userid 1001) id BC650C009; Fri, 12 Jun 2020 11:10:59 +0200 (CEST) Date: Fri, 12 Jun 2020 11:10:44 +0200 From: Dominique Martinet To: Wang Hai Cc: ericvh@gmail.com, lucho@ionkov.net, davem@davemloft.net, v9fs-developer@lists.sourceforge.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] 9p/trans_fd: Fix concurrency del of req_list in p9_fd_cancelled/p9_read_work Message-ID: <20200612091044.GA11129@nautica> References: <20200612090833.36149-1-wanghai38@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200612090833.36149-1-wanghai38@huawei.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wang Hai wrote on Fri, Jun 12, 2020: > p9_read_work and p9_fd_cancelled may be called concurrently. > In some cases, req->req_list may be deleted by both p9_read_work > and p9_fd_cancelled. > > We can fix it by ignoring replies associated with a cancelled > request and ignoring cancelled request if message has been received > before lock. > > Fixes: 60ff779c4abb ("9p: client: remove unused code and any reference to "cancelled" function") > Reported-by: syzbot+77a25acfa0382e06ab23@syzkaller.appspotmail.com > Signed-off-by: Wang Hai Thanks! looks good to me, I'll queue for 5.9 as well unless you're in a hurry. -- Dominique