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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 F1451C433E0 for ; Mon, 1 Jun 2020 13:17:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7279207DF for ; Mon, 1 Jun 2020 13:17:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591017448; bh=+xwGWIPiODPg1efNkqYPRoU0HTU1z1g9o1KdnrJRx78=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=kTerv0O5x+4Uxq8sTkBmTXd6gG3Ej51WH1z/fHrjs/kB7afo6HKpV/UYAI6J6IA+X aFKxSXLOknb/GukOjYRcMANZrTR6xoqVLOIcQtMkr8k4iZFW8aKVDDhHwDXZsy3MBZ X9jgGZ/5g2rqBp0DdIH5MIn6+ZcjEW2qJBA5V2kY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726287AbgFANR2 (ORCPT ); Mon, 1 Jun 2020 09:17:28 -0400 Received: from mail-pj1-f67.google.com ([209.85.216.67]:53621 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726075AbgFANR1 (ORCPT ); Mon, 1 Jun 2020 09:17:27 -0400 Received: by mail-pj1-f67.google.com with SMTP id i12so970071pju.3 for ; Mon, 01 Jun 2020 06:17:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=hFZ6VmcYqyPM08PfvBVOlGIssxARKDDkBROacFfg5Ck=; b=hvqaUx7Qhk53+L19sg0UtST4epmx5BK+FtEJ/EFthOIpppJmgNPyISTCIbEKngWbGr QDDCL8DbS/usjHdiKh7PXrvX0RS4J4Yi7kUtpctH8hXv+LF4oHMlH7WYa10LkYI4DKl4 oKr5BNWBf3l+auJjM202EQkQM/wxxGYar4bUqo67zta9xaNjyHOJg0D731A3c7xLok1g Gz3qRoPaggIprx9DwvFIk3nc14uFrS39xh/obD3mqsAjX/aMT5JfAQSpVcod76tDnN4m JeVdwPCwbbuUy3ZlfIGuBs7+axngpbS17jNDduYUa+z7WocjQohgZ1kKuyRjawKQz0qC FgIw== X-Gm-Message-State: AOAM533RVtYbpW3fyLigNqLI/sQ2w1E0Gbb+KKIA9+lgtO+8lZPOA+23 nqUjb3ky4cqAwWDfeLWNrys= X-Google-Smtp-Source: ABdhPJxw2rn3wia9BIDzDW1zUAIYizzEPtrFPk5f1QOIArACW42sqTfGX6xND0ZcqRubWo1Br/ii4A== X-Received: by 2002:a17:90a:8594:: with SMTP id m20mr1189463pjn.38.1591017447030; Mon, 01 Jun 2020 06:17:27 -0700 (PDT) Received: from 42.do-not-panic.com (42.do-not-panic.com. [157.230.128.187]) by smtp.gmail.com with ESMTPSA id b1sm4969011pjc.33.2020.06.01.06.17.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Jun 2020 06:17:25 -0700 (PDT) Received: by 42.do-not-panic.com (Postfix, from userid 1000) id 84F2740251; Mon, 1 Jun 2020 13:17:24 +0000 (UTC) Date: Mon, 1 Jun 2020 13:17:24 +0000 From: Luis Chamberlain To: Boris Sukholitko Cc: "Eric W. Biederman" , Andrew Morton , linux-fsdevel@vger.kernel.org, keescook@chromium.org, yzaikin@google.com Subject: Re: [PATCH] __register_sysctl_table: do not drop subdir Message-ID: <20200601131724.GK11244@42.do-not-panic.com> References: <20200527104848.GA7914@nixbox> <20200527125805.GI11244@42.do-not-panic.com> <20200528080812.GA21974@noodle> <874ks02m25.fsf@x220.int.ebiederm.org> <20200528142045.GP11244@42.do-not-panic.com> <20200531114432.GB22327@noodle> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200531114432.GB22327@noodle> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Sun, May 31, 2020 at 02:44:32PM +0300, Boris Sukholitko wrote: > On Thu, May 28, 2020 at 02:20:45PM +0000, Luis Chamberlain wrote: > > On Thu, May 28, 2020 at 09:04:02AM -0500, Eric W. Biederman wrote: > > > I see some recent (within the last year) fixes to proc_sysctl.c in this > > > area. Do you have those? It looks like bridge up and down is stressing > > > this code. Either those most recent fixes are wrong, your kernel is > > > missing them or this needs some more investigation. > > > > Thanks for the review Eric. > > > > Seconded. My first try at fixing it was incorrect, hopefully the new > attempt ([PATCH] get_subdir: do not drop new subdir if returning it) > I've just sent will fare better. > > > Boris, the elaborate deatils you provided would also be what would be > > needed for a commit log, specially since this is fixing a crash. If > > you confirm this is still present upstream by reproducing with a test > > case it would be wonderful. > > Yes. It is present in the upstream kernel. In my patch I've added > warning to catch this bad condition. The warning fires easily during > boot. Can you add a test case for this to reproduce in lib/test_sysct.c? Luis