From patchwork Mon Mar 29 07:56:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 411362 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=-19.0 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 E554AC433E3 for ; Mon, 29 Mar 2021 08:34:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF31C619CA for ; Mon, 29 Mar 2021 08:34:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233381AbhC2IeE (ORCPT ); Mon, 29 Mar 2021 04:34:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:52660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234528AbhC2IdR (ORCPT ); Mon, 29 Mar 2021 04:33:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C165961601; Mon, 29 Mar 2021 08:32:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617006725; bh=/2fTOAQOoXW4vjMQADVMxZOcP011X+DBEPZprpL4H5M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1WQjfWdCLL0NyD4xTee/xhqeqECPm9vj1576g4CqGQ+QmF+yTrf3MA4Q4dxXMrFyr UKEeb119gcNTBMyDFBxJ9Zv45xr6yJAuJHC0Sp/cE3UKY+2bAEsz3wi7ZOPPHa/QbU 0fvH3J2+BT3wCNKldKDZTPrtZoVckSZQfwxi+3iI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Neal Gompa , Josef Bacik , David Sterba Subject: [PATCH 5.11 068/254] btrfs: do not initialize dev replace for bad dev root Date: Mon, 29 Mar 2021 09:56:24 +0200 Message-Id: <20210329075635.388141565@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210329075633.135869143@linuxfoundation.org> References: <20210329075633.135869143@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 3cb894972f1809aa8d087c42e5e8b26c64b7d508 upstream. While helping Neal fix his broken file system I added a debug patch to catch if we were calling btrfs_search_slot with a NULL root, and this stack trace popped: we tried to search with a NULL root CPU: 0 PID: 1760 Comm: mount Not tainted 5.11.0-155.nealbtrfstest.1.fc34.x86_64 #1 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/22/2020 Call Trace: dump_stack+0x6b/0x83 btrfs_search_slot.cold+0x11/0x1b ? btrfs_init_dev_replace+0x36/0x450 btrfs_init_dev_replace+0x71/0x450 open_ctree+0x1054/0x1610 btrfs_mount_root.cold+0x13/0xfa legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x131/0x3d0 ? legacy_get_tree+0x27/0x40 ? btrfs_show_options+0x640/0x640 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 path_mount+0x441/0xa80 __x64_sys_mount+0xf4/0x130 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f644730352e Fix this by not starting the device replace stuff if we do not have a NULL dev root. Reported-by: Neal Gompa CC: stable@vger.kernel.org # 5.11+ Signed-off-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/dev-replace.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -80,6 +80,9 @@ int btrfs_init_dev_replace(struct btrfs_ struct btrfs_dev_replace_item *ptr; u64 src_devid; + if (!dev_root) + return 0; + path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM;