From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753520Ab3EHCks (ORCPT ); Tue, 7 May 2013 22:40:48 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:53932 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752133Ab3EHCkq (ORCPT ); Tue, 7 May 2013 22:40:46 -0400 X-Sasl-enc: vmVQgMJFeaZwIniDaYzIlSePm4pDfgS09ogegV8t1oCJ 1367980845 Subject: [PATCH] autofs4: translate pids to the right namespace for the daemon To: Linus Torvalds From: Ian Kent Cc: Serge Hallyn , Miklos Szeredi , autofs mailing list , Kernel Mailing List , Sukadev Bhattiprolu , Eric Biederman Date: Wed, 08 May 2013 10:40:42 +0800 Message-ID: <20130508024041.4314.4134.stgit@perseus.fritz.box> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Miklos Szeredi The PID and the TGID of the process tringgering the mount are sent to the daemon. Currently the global pid values are sent (ones valid in the initial pid namespace) but this is wrong if the autofs daemon itself is not running in the initial pid namespace. So send the pid values that are valid in the namespace of the autofs daemon. The namespace to use is taken from the oz_pgrp pid pointer, which was set at mount time to the mounting process' pid namespace. If the pid translation fails (the triggering process is in an unrelated pid namespace) then the automount fails with ENOENT. Signed-off-by: Miklos Szeredi Acked-by: Serge Hallyn Cc: Eric Biederman --- fs/autofs4/waitq.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 3db70da..309ca6b 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -353,11 +353,23 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, struct qstr qstr; char *name; int status, ret, type; + pid_t pid; + pid_t tgid; /* In catatonic mode, we don't wait for nobody */ if (sbi->catatonic) return -ENOENT; + /* + * Try translating pids to the namespace of the daemon. + * + * Zero means failure: we are in an unrelated pid namespace. + */ + pid = task_pid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); + tgid = task_tgid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); + if (pid == 0 || tgid == 0) + return -ENOENT; + if (!dentry->d_inode) { /* * A wait for a negative dentry is invalid for certain @@ -423,8 +435,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, wq->ino = autofs4_get_ino(sbi); wq->uid = current_uid(); wq->gid = current_gid(); - wq->pid = current->pid; - wq->tgid = current->tgid; + wq->pid = pid; + wq->tgid = tgid; wq->status = -EINTR; /* Status return if interrupted */ wq->wait_ctr = 2; mutex_unlock(&sbi->wq_mutex);