Mailinglist Archive: opensuse (2912 mails)

[Randall R Schulz <rschulz@xxxxxxxxx>]

Carlos,

On Tuesday 01 February 2005 11:42, Carlos E. R. wrote:
> The Tuesday 2005-02-01 at 08:11 -0800, Randall R Schulz wrote:
> > > Did anybody try setting the sticky bit?
> >
> > That doesn't seem likely to help. Presumably "/dev" is owned by and
> > only writable by root, so making it sticky isn't going to have any
> > real effect. Root was the only user that could have removed an
> > entry there and will still be able to even if the directory is
> > marked sticky.
>
> Probably, yes. Although I was thinking of the file, not the
> directory. I'm just hopping - I have never tried - that a "delete
> file" operation complains about the sticky bit having to be removed
> first. As I say, I don't know if that is the case, I'm just hoping.

The sticky bit has two interpretations, one ancient and, I think, 
obsolete and the other newer and still relevant:

1/old) The executable text (instructions) of pure binary executables 
with their sticky bit set remain in the swap space even when no process 
is executing them. Then instead of recreating their core image from 
scratch (from the executable file contents) the next time that program 
is executed, it can simply be swapped in again.

2/new) Directories whose sticky bit is set can be made writable by all 
while allowing only the owner of a file to remove it (more precisely, a 
directory entry referring to it) from that directory.

As ever, root is not subject to the restriction created by the second 
use of the sticky bit.

So I don't see how making /dev or a device entry therein sticky is going 
to have any actual effect on the operation of the system.


>        Carlos Robinson


Randall Schulz