Coda File System

Re: spurious Permission denied offline on apparently working setup

From: Jan Harkes <jaharkes_at_cs.cmu.edu>
Date: Fri, 26 Jul 2002 09:18:24 -0400
On Fri, Jul 26, 2002 at 02:37:36PM +0200, Steffen Neumann wrote:
> I encountered the following strange behaviour 
> in the last days, and I'd like to know if it 
> is a bug with coda, or I got something wrong.
> 
> 0) I'm online. My homes volume is there,
>    Connected, I got a valid token
> 
> 1) I am hoarding my home volume
> 
> 2) At home I use my (expired) token -fromfile 
>    to login.
> 
> 3) All files are there. Fine.
> 
> 4) Sometimes (and here's the problem)
>    files in a directory are write protected,
>    whereas other directories in the same volume 
>    are not (Usually I copy the files to /home/user
>    and copy them back when I get back to college).
>    Those files were fine when I worked online.
> 
> What might cause this ? What can I do to examine the cause 
> for this behaviour ? Does it make a difference
> whether the files were hoarded by ma on console#1
> or me as root ('cause I didn't want to walk over
> to do the hoarding ...) ? I'd like to be prepared 
> when this happens the next time.

Permissions are cached during access. I'm not entirely sure, but I
believe I once noticed that the hoard daemon accesses objects with the
permissions of whoever executed the 'hoard walk' command (it should be
the user that originally added the hoard entry), so that 'root' will
have permission to modify the object, but your local user-id only has
System:AnyUser priviledges which are insufficient to actually do any
modifications.

I'll try to read through the hoarding code today to see if I can
identify any culprits of this identity confusion.

Jan
Received on 2002-07-26 09:19:54