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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 75AD7C10DCE for ; Fri, 13 Mar 2020 15:45:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E5D120753 for ; Fri, 13 Mar 2020 15:45:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="DjVyvdI6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726605AbgCMPpq (ORCPT ); Fri, 13 Mar 2020 11:45:46 -0400 Received: from mail-qk1-f193.google.com ([209.85.222.193]:37886 "EHLO mail-qk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727174AbgCMPpD (ORCPT ); Fri, 13 Mar 2020 11:45:03 -0400 Received: by mail-qk1-f193.google.com with SMTP id z25so8342251qkj.4 for ; Fri, 13 Mar 2020 08:45:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=gd+Y9n7g/izMwHOhUhGhejD80gYG0EI0lQyPcUpWVoU=; b=DjVyvdI63czycwj50bO5NaNC1KcMCvNq8F2IZG8BdGCJv5eyAPICWI2SqwE7VTUJoA jacA7C6vv5guxckuW6lNkj9DTv3CAVac0sX/o38VYPlEKImZchP6fLkKutUX10tRAJpf ka+JKju4nLNuGVZe6qoqovf80VH2No7Eqvj77oxL/3HhNi1M6KONajQAGAFCg4NrYurl 3+KBal/gUtY3EkdRLKW2fXxX1ieS/IqD6nEcPDodR4A3RH5fwwIfUXfuDYiTEgZai4QM WWo9FDHqYEatRKwsxcYDcgqN7NZ6wXKKENAP26B/l36sUNro4OC4UT7EY8QWJrVdc4Sj O42g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=gd+Y9n7g/izMwHOhUhGhejD80gYG0EI0lQyPcUpWVoU=; b=celd+b10l0Rnsgib87AND+eRI3jDKNe7ASsGiRuLuqIY27rup/hgTDY+Odjur6AHxJ wdQSfqQKUfvkqc/PS0mPdZVnU/k877XdwB9tGVCyEYkRYGwHzfqa3VVD4JRYBS0ga7p1 9I/jYnQoVg8agkSc/DAxZGi38FLl3KOt44wdtnBP4afdauYBreA7ebHGhxdnSxVAFFko mycnzw23yGZXolkjZp02PawVRwJuRAo+qBZb64ZOEmrnK3TA9Oqt0G5NTsdNdFQa00fH o0eeYlKF5wXc4XJuwyj2OdIf5bpckeWHCC0Zd9oZCcgHTv6kPdcXFydLA9jab2yiwMqV qKWg== X-Gm-Message-State: ANhLgQ0sxfk7xmxL7UV+/VEhzLal0pmXrW4/IComAiLiBCHyG1eBVOpl xjw1Dozgl6Bj1te6I9fJF0GP71aU0hE= X-Google-Smtp-Source: ADFU+vv6uCeSRa5ji26Z5a+b3yQDwsjoBjRzieOCo2NRlrRlIpn507RZvbpJf1yIH/K2F1niZvyyhg== X-Received: by 2002:ae9:dc04:: with SMTP id q4mr13836054qkf.216.1584114302226; Fri, 13 Mar 2020 08:45:02 -0700 (PDT) Received: from localhost ([107.15.81.208]) by smtp.gmail.com with ESMTPSA id h47sm11537453qtb.75.2020.03.13.08.45.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 Mar 2020 08:45:01 -0700 (PDT) From: Josef Bacik To: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 6/8] btrfs: clear BTRFS_ROOT_DEAD_RELOC_TREE before dropping the reloc root Date: Fri, 13 Mar 2020 11:44:46 -0400 Message-Id: <20200313154448.53461-7-josef@toxicpanda.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200313154448.53461-1-josef@toxicpanda.com> References: <20200313154448.53461-1-josef@toxicpanda.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Qu put this in place in order to avoid a use after free in init_reloc_root. However a previous patch in this series makes the use after free impossible because at this point we no longer have a reloc_control set on the fs_info. So move this to be coupled with clearing the root->reloc_root so we're consistent with all other operations of the reloc root. Signed-off-by: Josef Bacik --- fs/btrfs/relocation.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 9c8a4a4b2bde..5bbed0ea26e1 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -2291,18 +2291,19 @@ static int clean_dirty_subvols(struct reloc_control *rc) list_del_init(&root->reloc_dirty_list); root->reloc_root = NULL; - if (reloc_root) { - - ret2 = btrfs_drop_snapshot(reloc_root, NULL, 0, 1); - if (ret2 < 0 && !ret) - ret = ret2; - } /* * Need barrier to ensure clear_bit() only happens after * root->reloc_root = NULL. Pairs with have_reloc_root. */ smp_wmb(); clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); + + if (reloc_root) { + + ret2 = btrfs_drop_snapshot(reloc_root, NULL, 0, 1); + if (ret2 < 0 && !ret) + ret = ret2; + } btrfs_put_root(root); } else { /* Orphan reloc tree, just clean it up */ -- 2.24.1