lkml.org 
[lkml]   [2018]   [Feb]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC 3/3] seccomp: add a way to get a listener fd from ptrace
On Sun, Feb 4, 2018 at 2:49 AM, Tycho Andersen <tycho@tycho.ws> wrote:
> As an alternative to SECCOMP_FILTER_FLAG_GET_LISTENER, perhaps a ptrace()
> version which can acquire filters is useful. There are at least two reasons
> this is preferable, even though it uses ptrace:
>
> 1. You can control tasks that aren't cooperating with you
> 2. You can control tasks whose filters block sendmsg() and socket(); if the
> task installs a filter which blocks these calls, there's no way with
> SECCOMP_FILTER_FLAG_GET_LISTENER to get the fd out to the privileged task.

I got worried for a second that this would get us into a many-to-many
state, but I see init_listener enforces a single listener per filter.
Whew. Seems legit. :)

-Kees

--
Kees Cook
Pixel Security

\
 
 \ /
  Last update: 2018-02-13 22:33    [W:0.135 / U:0.956 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site