lkml.org 
[lkml]   [2012]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Re: [PATCH] subsystem: pr??oc filesystem
On Sun, Dec 16, 2012 at 04:02:03PM +0400, tux2002@front.ru wrote:
> Not, this permissions saved for all users for later, check please.

... and that's why it's bogus. umask of whoever had done lookup for
/proc/<something> affects everybody else. For as long as the thing stays
in dcache. At which point it's up for grabs (in that sense) again.
Do (umask 777; ls -l /proc) with your kernel and watch the results.
Note that you don't need to be root to cause that - anyone can do it.

Realize that dentries and inodes in /proc/<pid>/* are created on demand
whenever somebody does a lookup. So running ps(1) suddenly makes you
a creator of a bunch of those. Unless somebody else had done ps(1) (or
ls -l /proc, or...) first. Basing any security decisions on _that_ is
insane.


\
 
 \ /
  Last update: 2012-12-16 16:01    [W:0.038 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site