From patchwork Fri Dec 6 14:45:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 11276621 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 55D43138D for ; Fri, 6 Dec 2019 14:46:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3456921835 for ; Fri, 6 Dec 2019 14:46:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="X2noEWcL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726538AbfLFOqT (ORCPT ); Fri, 6 Dec 2019 09:46:19 -0500 Received: from mail-qt1-f194.google.com ([209.85.160.194]:46274 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726268AbfLFOqS (ORCPT ); Fri, 6 Dec 2019 09:46:18 -0500 Received: by mail-qt1-f194.google.com with SMTP id 38so7297379qtb.13 for ; Fri, 06 Dec 2019 06:46:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=oc0fPepNq7xu/SGSZfzXEwOFvheWAxvSaU04owUSiAc=; b=X2noEWcLaHYQFK9TBPYSvRHEOYkf1AG7KWe8Pc6FVKM1/RU87s9rPchklRDeeMDQEj 5jmK5Rdgey+E/FRKYQpZkNFndQZ+khWoDGqAbU+nBM4BCS5lRKOZmsXn0WccFS2KgUFM G2zmM0k+IzZJwOANjz2tZXdj5poyrorY1wsxpLJL76XkwkPkLopQhDHrnCho/y2jpy4e M01HKzT4PFrUdeIENernAASx8oB7NFZEXCsNvLr89RE9QySS5Egn4nXvJx+qrpyoWM4D JzUBfOljvbBhB6MyueBOLsYrRWZwCGZurXPFM0gjLBYEHZ+yvIi9+XNuyIu0vUsMGlwP gLpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=oc0fPepNq7xu/SGSZfzXEwOFvheWAxvSaU04owUSiAc=; b=aBAJd7egi2JK8c6d/TVP7W2+1oiMEVYwhT8N3YSrVaXgn30xV1NIgZkp0+zE0vYT10 CVMJQHdMj+NqSTuMeWqJH9yRnyhs8zg7F06+7FdahesyG3DCv/PndUJlEL/YRjsE8qMW aHQrzAt5+NxeZmOgOJGBwyRHiv6d4w6rxRRXtLHp/oXnU9ju+umZr7ZwFdBcY+Wt4v/M trPgPpaVb7IWhr3AQ17MZYg9M7lWbqK9m4VXtq4wKxkXRxsCICzDZw2dFuR16ZSDktBJ 0eZMLULS4OixMYOdRA6OCQCifCgWLiTeeiqmkhU7KIbdlswYqfMYRQnDfdallusqH2Xe 2qkA== X-Gm-Message-State: APjAAAW28EgpRoMnkOuUIAYzO4PdrPnDm2Wl++9QaPvaAgeFSwNLOYSL nQjTeCcU68Um3Y32792zhYKWRk3Zwdlf+w== X-Google-Smtp-Source: APXvYqx7Kh6RVIajzn1cJgAPDaoWvH3vh4IIr0rvy+rwbVlhATTJcslLS357WmOQO896O2fNcAtcuQ== X-Received: by 2002:ac8:6f3b:: with SMTP id i27mr13091419qtv.145.1575643576874; Fri, 06 Dec 2019 06:46:16 -0800 (PST) Received: from localhost ([107.15.81.208]) by smtp.gmail.com with ESMTPSA id e2sm2953368qkl.3.2019.12.06.06.46.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Dec 2019 06:46:16 -0800 (PST) From: Josef Bacik To: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 20/44] btrfs: hold a ref on the root in btrfs_search_path_in_tree_user Date: Fri, 6 Dec 2019 09:45:14 -0500 Message-Id: <20191206144538.168112-21-josef@toxicpanda.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191206144538.168112-1-josef@toxicpanda.com> References: <20191206144538.168112-1-josef@toxicpanda.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org We can wander into a different root, so grab a ref on the root we look up. Later on we make root = fs_info->tree_root so we need this separate out label to make sure we do the right cleanup only in the case we're looking up a different root. Signed-off-by: Josef Bacik --- fs/btrfs/ioctl.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index b8b5432423e6..2eb5a5dc07bd 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2432,6 +2432,10 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, ret = PTR_ERR(root); goto out; } + if (!btrfs_grab_fs_root(root)) { + ret = -ENOENT; + goto out; + } key.objectid = dirid; key.type = BTRFS_INODE_REF_KEY; @@ -2439,15 +2443,15 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) { - goto out; + goto out_put; } else if (ret > 0) { ret = btrfs_previous_item(root, path, dirid, BTRFS_INODE_REF_KEY); if (ret < 0) { - goto out; + goto out_put; } else if (ret > 0) { ret = -ENOENT; - goto out; + goto out_put; } } @@ -2461,7 +2465,7 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, total_len += len + 1; if (ptr < args->path) { ret = -ENAMETOOLONG; - goto out; + goto out_put; } *(ptr + len) = '/'; @@ -2472,10 +2476,10 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, ret = btrfs_previous_item(root, path, dirid, BTRFS_INODE_ITEM_KEY); if (ret < 0) { - goto out; + goto out_put; } else if (ret > 0) { ret = -ENOENT; - goto out; + goto out_put; } leaf = path->nodes[0]; @@ -2483,26 +2487,26 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, btrfs_item_key_to_cpu(leaf, &key2, slot); if (key2.objectid != dirid) { ret = -ENOENT; - goto out; + goto out_put; } temp_inode = btrfs_iget(sb, &key2, root); if (IS_ERR(temp_inode)) { ret = PTR_ERR(temp_inode); - goto out; + goto out_put; } ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC); iput(temp_inode); if (ret) { ret = -EACCES; - goto out; + goto out_put; } if (key.offset == upper_limit.objectid) break; if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { ret = -EACCES; - goto out; + goto out_put; } btrfs_release_path(path); @@ -2513,6 +2517,7 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, memmove(args->path, ptr, total_len); args->path[total_len] = '\0'; + btrfs_put_fs_root(root); btrfs_release_path(path); } @@ -2551,6 +2556,9 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, out: btrfs_free_path(path); return ret; +out_put: + btrfs_put_fs_root(root); + goto out; } static noinline int btrfs_ioctl_ino_lookup(struct file *file,