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=-19.4 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=unavailable 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 351AAC46461 for ; Mon, 10 May 2021 12:16:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1BA81613C8 for ; Mon, 10 May 2021 12:16:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343744AbhEJMOR (ORCPT ); Mon, 10 May 2021 08:14:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:46276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236659AbhEJLIZ (ORCPT ); Mon, 10 May 2021 07:08:25 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0AADE619B2; Mon, 10 May 2021 11:02:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620644573; bh=Y7ekhyb+XSJ4OgJm7ILGcgfzw8TrCe8/USJ16LFGbGA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sbPMF7XcJhrQr3hOhuLT1eJZstS5uhw45IUpkx293UzQ+q6NBI3RKbdcIumJAnseG 6Wqxz7o9SCH1Hbg+6sWv6QV6MhOu+/3qm8WwsNKRTjEK0kkYhAx/SRysrhJfA0d52R 1bffjUSuUkGc0aWkAbyLH/DLCLQDezramo5KSwbo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Josef Bacik , David Sterba , Sasha Levin Subject: [PATCH 5.12 137/384] btrfs: do proper error handling in create_reloc_root Date: Mon, 10 May 2021 12:18:46 +0200 Message-Id: <20210510102019.410447094@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102014.849075526@linuxfoundation.org> References: <20210510102014.849075526@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 [ Upstream commit 84c50ba5214c2f3c1be4a931d521ec19f55dfdc8 ] We do memory allocations here, read blocks from disk, all sorts of operations that could easily fail at any given point. Instead of panicing the box, simply return the error back up the chain, all callers at this point have proper error handling. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/relocation.c | 34 ++++++++++++++++++++++++++++------ 1 file changed, 28 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index bf269ee17e68..b445b3073dea 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -733,10 +733,12 @@ static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, struct extent_buffer *eb; struct btrfs_root_item *root_item; struct btrfs_key root_key; - int ret; + int ret = 0; + bool must_abort = false; root_item = kmalloc(sizeof(*root_item), GFP_NOFS); - BUG_ON(!root_item); + if (!root_item) + return ERR_PTR(-ENOMEM); root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; root_key.type = BTRFS_ROOT_ITEM_KEY; @@ -748,7 +750,9 @@ static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, /* called by btrfs_init_reloc_root */ ret = btrfs_copy_root(trans, root, root->commit_root, &eb, BTRFS_TREE_RELOC_OBJECTID); - BUG_ON(ret); + if (ret) + goto fail; + /* * Set the last_snapshot field to the generation of the commit * root - like this ctree.c:btrfs_block_can_be_shared() behaves @@ -769,9 +773,16 @@ static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, */ ret = btrfs_copy_root(trans, root, root->node, &eb, BTRFS_TREE_RELOC_OBJECTID); - BUG_ON(ret); + if (ret) + goto fail; } + /* + * We have changed references at this point, we must abort the + * transaction if anything fails. + */ + must_abort = true; + memcpy(root_item, &root->root_item, sizeof(*root_item)); btrfs_set_root_bytenr(root_item, eb->start); btrfs_set_root_level(root_item, btrfs_header_level(eb)); @@ -789,14 +800,25 @@ static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, ret = btrfs_insert_root(trans, fs_info->tree_root, &root_key, root_item); - BUG_ON(ret); + if (ret) + goto fail; + kfree(root_item); reloc_root = btrfs_read_tree_root(fs_info->tree_root, &root_key); - BUG_ON(IS_ERR(reloc_root)); + if (IS_ERR(reloc_root)) { + ret = PTR_ERR(reloc_root); + goto abort; + } set_bit(BTRFS_ROOT_SHAREABLE, &reloc_root->state); reloc_root->last_trans = trans->transid; return reloc_root; +fail: + kfree(root_item); +abort: + if (must_abort) + btrfs_abort_transaction(trans, ret); + return ERR_PTR(ret); } /* -- 2.30.2