Re: SCSI device numbering (was: Re: Ideas for v2.1

Chris Evans (
Tue, 2 Jul 1996 18:50:47 +0100 (BST)

On Tue, 2 Jul 1996, Linus Torvalds wrote:

> The /proc filesystem is not meant to be able to handle complexities like
> this: it's meant to be a simple window to the kernel. It _looks_ trivial to
> have the /proc filesystem have default protections for the files, and
> then let the administrator override them with chmod/chown, but it gets
> very non-trivial indeed when you want to mount the /proc filesystem on
> multiple points on a machine at the same time (which _is_ possible, and
> _should_ be possible).

I am currently running 2.0 + a patch of my own design which adds a
(mode_t) variable to struct task. This variable represents the permission
on a /proc/<pid> directory, and is changeable via chmod() by the owner of
a given task. Works like a charm, a user does chmod og-rwx /proc/<pid>
and the process magically disappers from all displays of ps/top/etc.
executed by other users. Good for privacy. Option to use chmod on just
the cmdline of a process is provided too.

Since all instances of /proc will access just this _one_ variable
(p->procperm), will I escape the troubles outlined in the paragraph
quoted above..?