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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 4E1D3C2BA19 for ; Thu, 23 Apr 2020 23:24:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 274E820784 for ; Thu, 23 Apr 2020 23:24:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729231AbgDWXYY (ORCPT ); Thu, 23 Apr 2020 19:24:24 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48316 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728148AbgDWXG3 (ORCPT ); Thu, 23 Apr 2020 19:06:29 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jRkvJ-0004aN-HG; Fri, 24 Apr 2020 00:06:25 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jRkvI-00E6gb-Jx; Fri, 24 Apr 2020 00:06:24 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Greg Kroah-Hartman" , "Jeff Mahoney" , "Liu Bo" , "Filipe Manana" , "Ben Hutchings" Date: Fri, 24 Apr 2020 00:04:18 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 031/245] Btrfs: fix BUG_ON in btrfs_mark_buffer_dirty In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Liu Bo commit ef85b25e982b5bba1530b936e283ef129f02ab9d upstream. This can only happen with CONFIG_BTRFS_FS_CHECK_INTEGRITY=y. Commit 1ba98d0 ("Btrfs: detect corruption when non-root leaf has zero item") assumes that a leaf is its root when leaf->bytenr == btrfs_root_bytenr(root), however, we should not use btrfs_root_bytenr(root) since it's mainly got updated during committing transaction. So the check can fail when doing COW on this leaf while it is a root. This changes to use "if (leaf == btrfs_root_node(root))" instead, just like how we check whether leaf is a root in __btrfs_cow_block(). Fixes: 1ba98d086fe3 (Btrfs: detect corruption when non-root leaf has zero item) Reported-by: Jeff Mahoney Signed-off-by: Liu Bo Reviewed-by: Filipe Manana Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- fs/btrfs/disk-io.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -533,13 +533,17 @@ static noinline int check_leaf(struct bt * open_ctree() some roots has not yet been set up. */ if (!IS_ERR_OR_NULL(check_root)) { + struct extent_buffer *eb; + + eb = btrfs_root_node(check_root); /* if leaf is the root, then it's fine */ - if (leaf->start != - btrfs_root_bytenr(&check_root->root_item)) { + if (leaf != eb) { CORRUPT("non-root leaf's nritems is 0", - leaf, root, 0); + leaf, check_root, 0); + free_extent_buffer(eb); return -EIO; } + free_extent_buffer(eb); } return 0; }