From mboxrd@z Thu Jan 1 00:00:00 1970 From: "William A.(Andy) Adamson" Subject: Re: NFS4 crack Date: Tue, 20 Sep 2005 11:10:31 -0400 Message-ID: <20050920151031.B15011BAC2@citi.umich.edu> References: <20050918102100.GA23463@lst.de> <20050918143615.GA3428@fieldses.org> <20050919103547.GA8998@lst.de> <20050919203143.GC26122@fieldses.org> <20050920124908.GA30842@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "J. Bruce Fields" , Christoph Hellwig , akpm@osdl.org, neilb@cse.unsw.edu.au, andros@citi.umich.edu, linux-fsdevel@vger.kernel.org, andros@citi.umich.edu Return-path: Received: from citi.umich.edu ([141.211.133.111]:62802 "EHLO citi.umich.edu") by vger.kernel.org with ESMTP id S964904AbVITPKc (ORCPT ); Tue, 20 Sep 2005 11:10:32 -0400 To: Greg KH In-reply-to: <20050920124908.GA30842@kroah.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org > On Mon, Sep 19, 2005 at 04:31:43PM -0400, J. Bruce Fields wrote: > > We'd need two pieces of user<->kernel interface: > > > > 1. An upcall to userspace to tell it about new client state. We > > also need to be able to wait for userspace to commit something > > to disk, as the information has to survive a reboot. > > 2. A way for userspace to dump recorded state to the kernel the > > next time nfsd starts up. > > > > Number 1 could be done with something like hotplug, I guess. (It can be > > told to wait for the userspace helper to exit, right?) > > Well, calling /sbin/hotplug itself can't be told to wait, especially as > that value is being set to NULL by most distros these days, as they are > using netlink instead. > call_usermodehelper_keys() with the wait status is what we are thinking of using for #1. note that the keyring code which uses call_usermodehelper_keys also hard codes an executable name. security/keys/request_key.c: /* set up the argument list */ i = 0; argv[i++] = "/sbin/request-key"; argv[i++] = (char *) op; -->Andy