From patchwork Mon Mar 1 16:13:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 390188 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=-18.8 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 EF4AEC43333 for ; Mon, 1 Mar 2021 16:44:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBCAA65033 for ; Mon, 1 Mar 2021 16:44:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235145AbhCAQnJ (ORCPT ); Mon, 1 Mar 2021 11:43:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:41538 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232781AbhCAQgl (ORCPT ); Mon, 1 Mar 2021 11:36:41 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 405D964F3F; Mon, 1 Mar 2021 16:26:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614615995; bh=vADTKI8wPLnKUNC2dzoozutChBFw9DZD3N3wCUHYUAg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CWX9cOzYZqnmr304TFEjn0SqYGZDdfzi8mo+4P7kbxk8I2yPk0Qgx1QiZ+C6HD3LP w0GH++cRqk84cU2PhBdzxqwt35NijNNDf1rDEAOKbRG8SmEGu7FMl1oE+GOBxzgz86 aUpbCRZQlF8OQWpOuiVr8gnBVDBllMueQm2icgVk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Josef Bacik , David Sterba Subject: [PATCH 4.9 103/134] btrfs: fix reloc root leak with 0 ref reloc roots on recovery Date: Mon, 1 Mar 2021 17:13:24 +0100 Message-Id: <20210301161018.637561519@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161013.585393984@linuxfoundation.org> References: <20210301161013.585393984@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Josef Bacik commit c78a10aebb275c38d0cfccae129a803fe622e305 upstream. When recovering a relocation, if we run into a reloc root that has 0 refs we simply add it to the reloc_control->reloc_roots list, and then clean it up later. The problem with this is __del_reloc_root() doesn't do anything if the root isn't in the radix tree, which in this case it won't be because we never call __add_reloc_root() on the reloc_root. This exit condition simply isn't correct really. During normal operation we can remove ourselves from the rb tree and then we're meant to clean up later at merge_reloc_roots() time, and this happens correctly. During recovery we're depending on free_reloc_roots() to drop our references, but we're short-circuiting. Fix this by continuing to check if we're on the list and dropping ourselves from the reloc_control root list and dropping our reference appropriately. Change the corresponding BUG_ON() to an ASSERT() that does the correct thing if we aren't in the rb tree. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/relocation.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -1335,9 +1335,7 @@ static void __del_reloc_root(struct btrf RB_CLEAR_NODE(&node->rb_node); } spin_unlock(&rc->reloc_root_tree.lock); - if (!node) - return; - BUG_ON((struct btrfs_root *)node->data != root); + ASSERT(!node || (struct btrfs_root *)node->data == root); } spin_lock(&root->fs_info->trans_lock);