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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E58EFC433F5 for ; Mon, 24 Jan 2022 20:39:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1387748AbiAXUhN (ORCPT ); Mon, 24 Jan 2022 15:37:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356214AbiAXUOw (ORCPT ); Mon, 24 Jan 2022 15:14:52 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E892C09B052; Mon, 24 Jan 2022 11:37:53 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 26BF8B81238; Mon, 24 Jan 2022 19:37:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A7D2C340E5; Mon, 24 Jan 2022 19:37:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643053070; bh=kEkyCNZBvcElxWMg8I/Xi3Hk6q+Di49XLMC0Q1kRaME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iuGGVG6wLLETne1DU8lgcs5UzwxuDc9Dndio352zTUQl6nFfAoy+WIRIUnBKiaxTX IvzFQSBBWsZIbNgVHl1xDl2vL1Gde0jAqTQS9zFVAbRpuqj653FV22taKLxScA7Yh2 rJnFr/8LufcM5NQZvpyuv2dmJwKsCy6inCCe8KzU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nikolay Borisov , Josef Bacik , David Sterba Subject: [PATCH 5.4 266/320] btrfs: check the root node for uptodate before returning it Date: Mon, 24 Jan 2022 19:44:10 +0100 Message-Id: <20220124184003.027352454@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183953.750177707@linuxfoundation.org> References: <20220124183953.750177707@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josef Bacik commit 120de408e4b97504a2d9b5ca534b383de2c73d49 upstream. Now that we clear the extent buffer uptodate if we fail to write it out we need to check to see if our root node is uptodate before we search down it. Otherwise we could return stale data (or potentially corrupt data that was caught by the write verification step) and think that the path is OK to search down. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Nikolay Borisov Signed-off-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/ctree.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -2658,12 +2658,9 @@ static struct extent_buffer *btrfs_searc { struct btrfs_fs_info *fs_info = root->fs_info; struct extent_buffer *b; - int root_lock; + int root_lock = 0; int level = 0; - /* We try very hard to do read locks on the root */ - root_lock = BTRFS_READ_LOCK; - if (p->search_commit_root) { /* * The commit roots are read only so we always do read locks, @@ -2701,6 +2698,9 @@ static struct extent_buffer *btrfs_searc goto out; } + /* We try very hard to do read locks on the root */ + root_lock = BTRFS_READ_LOCK; + /* * If the level is set to maximum, we can skip trying to get the read * lock. @@ -2727,6 +2727,17 @@ static struct extent_buffer *btrfs_searc level = btrfs_header_level(b); out: + /* + * The root may have failed to write out at some point, and thus is no + * longer valid, return an error in this case. + */ + if (!extent_buffer_uptodate(b)) { + if (root_lock) + btrfs_tree_unlock_rw(b, root_lock); + free_extent_buffer(b); + return ERR_PTR(-EIO); + } + p->nodes[level] = b; if (!p->skip_locking) p->locks[level] = root_lock;