lkml.org 
[lkml]   [2011]   [Jun]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: How to temporary change 'current' (task)
From
Date
On Fri, 2011-06-17 at 12:36 +0400, Vasiliy Kulikov wrote:
> Hi,
>
> I wonder whether there is a simple way to temporary switch 'current' to
> another task and then switch it back with minimum side effects?

No.

> I need
> it to call "reversed" ptrace_may_access() with swapped current and
> target task. Introducing ptrace_task_may_access_me() would produce too
> much noise in LSM (it also needs reversed security_ptrace_access_check()),
> which is too loud for my needs.
>
> Specifically, I need it to filter taskstats and proc connector requests
> for a restriction of getting other processes' information:
>
> http://permalink.gmane.org/gmane.linux.kernel/1155354
>
> As the check is handled in the context of the ptrace target process,
> ptrace_may_access() doesn't fit my needs.

looking at __ptrace_may_access() it doesn't look too hard to make it
take two task arguments and use __task_cred() twice instead of
current_cred().

It of course needs extending security_ptrace_access_check() as well, but
that comes with the territory.


\
 
 \ /
  Last update: 2011-06-17 11:33    [W:0.781 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site