From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: [PATCH] vfs: Is mounted should be testing mnt_ns for NULL or error. Date: Mon, 20 Jan 2014 15:26:15 -0800 Message-ID: <87lhya6xrc.fsf@xmission.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , To: Al Viro Return-path: Received: from out01.mta.xmission.com ([166.70.13.231]:46826 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775AbaATX01 (ORCPT ); Mon, 20 Jan 2014 18:26:27 -0500 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: A bug was introduced with the is_mounted helper function in commit f7a99c5b7c8bd3d3f533c8b38274e33f3da9096e Author: Al Viro Date: Sat Jun 9 00:59:08 2012 -0400 get rid of ->mnt_longterm it's enough to set ->mnt_ns of internal vfsmounts to something distinct from all struct mnt_namespace out there; then we can just use the check for ->mnt_ns != NULL in the fast path of mntput_no_expire() Signed-off-by: Al Viro The intent was to test if the real_mount(vfsmount)->mnt_ns was NULL_OR_ERR but the code is actually testing real_mount(vfsmount) and always returning true. The result is d_absolute_path returning paths it should be hiding. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" --- fs/mount.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/fs/mount.h b/fs/mount.h index d64c594be6c4..a17458ca6f29 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -74,7 +74,7 @@ static inline int mnt_has_parent(struct mount *mnt) static inline int is_mounted(struct vfsmount *mnt) { /* neither detached nor internal? */ - return !IS_ERR_OR_NULL(real_mount(mnt)); + return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns); } extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *); -- 1.7.5.4