Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754323AbbFJQFP (ORCPT ); Wed, 10 Jun 2015 12:05:15 -0400 Received: from ip4-83-240-67-251.cust.nbox.cz ([83.240.67.251]:36027 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933799AbbFJP1m (ORCPT ); Wed, 10 Jun 2015 11:27:42 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, "Eric W. Biederman" , Jiri Slaby Subject: [PATCH 3.12 011/111] mnt: Fail collect_mounts when applied to unmounted mounts Date: Wed, 10 Jun 2015 17:26:00 +0200 Message-Id: <6ab282fe6d43027b3b1ef820b3798aae8fdb432b.1433943052.git.jslaby@suse.cz> X-Mailer: git-send-email 2.4.2 In-Reply-To: <93091169a673f49c2574cddf1ef858cf0704f646.1433943052.git.jslaby@suse.cz> References: <93091169a673f49c2574cddf1ef858cf0704f646.1433943052.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2004 Lines: 58 From: "Eric W. Biederman" 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit cd4a40174b71acd021877341684d8bb1dc8ea4ae upstream. The only users of collect_mounts are in audit_tree.c In audit_trim_trees and audit_add_tree_rule the path passed into collect_mounts is generated from kern_path passed an audit_tree pathname which is guaranteed to be an absolute path. In those cases collect_mounts is obviously intended to work on mounted paths and if a race results in paths that are unmounted when collect_mounts it is reasonable to fail early. The paths passed into audit_tag_tree don't have the absolute path check. But are used to play with fsnotify and otherwise interact with the audit_trees, so again operating only on mounted paths appears reasonable. Avoid having to worry about what happens when we try and audit unmounted filesystems by restricting collect_mounts to mounts that appear in the mount tree. Signed-off-by: "Eric W. Biederman" Signed-off-by: Jiri Slaby --- fs/namespace.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/fs/namespace.c b/fs/namespace.c index 247f34d43dda..185cd1aefa14 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1467,8 +1467,11 @@ struct vfsmount *collect_mounts(struct path *path) { struct mount *tree; namespace_lock(); - tree = copy_tree(real_mount(path->mnt), path->dentry, - CL_COPY_ALL | CL_PRIVATE); + if (!check_mnt(real_mount(path->mnt))) + tree = ERR_PTR(-EINVAL); + else + tree = copy_tree(real_mount(path->mnt), path->dentry, + CL_COPY_ALL | CL_PRIVATE); namespace_unlock(); if (IS_ERR(tree)) return ERR_CAST(tree); -- 2.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/