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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 0FC18C43603 for ; Mon, 9 Dec 2019 16:14:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCF6620836 for ; Mon, 9 Dec 2019 16:14:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726826AbfLIQOs (ORCPT ); Mon, 9 Dec 2019 11:14:48 -0500 Received: from mx2.suse.de ([195.135.220.15]:48602 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726607AbfLIQOr (ORCPT ); Mon, 9 Dec 2019 11:14:47 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 40283ACE0; Mon, 9 Dec 2019 16:14:46 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 67BA4DA783; Mon, 9 Dec 2019 17:14:39 +0100 (CET) Date: Mon, 9 Dec 2019 17:14:39 +0100 From: David Sterba To: fdmanana@kernel.org Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH] Btrfs: fix removal logic of the tree mod log that leads to use-after-free issues Message-ID: <20191209161439.GK2734@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, fdmanana@kernel.org, linux-btrfs@vger.kernel.org References: <20191206122739.27195-1-fdmanana@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191206122739.27195-1-fdmanana@kernel.org> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Dec 06, 2019 at 12:27:39PM +0000, fdmanana@kernel.org wrote: > From: Filipe Manana > > When a tree mod log user no longer needs to use the tree it calls > btrfs_put_tree_mod_seq() to remove itself from the list of users and > delete all no longer used elements of the tree's red black tree, which > should be all elements with a sequence number less then our equals to > the caller's sequence number. However the logic is broken because it > can delete and free elements from the red black tree that have a > sequence number greater then the caller's sequence number: Added to misc-next, thanks.