lkml.org 
[lkml]   [2017]   [Jun]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1] shebang: restrict python interactive prompt/interpreter
On Mon, 12 Jun 2017 10:27:24 -0400
Mimi Zohar <zohar@linux.vnet.ibm.com> wrote:

> On Sun, 2017-06-11 at 22:32 -0400, Mimi Zohar wrote:
> > On Sun, 2017-06-11 at 13:44 +0200, Mickaël Salaün wrote:
>
> > > Using filesystem xattr seems like a good idea for this kind of
> > > exceptions and instead of a hardcoded interpreter path. Something like
> > > "security.tpe.interpreter=1|2" (bitmask for interpreter-only and/or CLI)
> > > and "security.tpe.environment=HOME,LOGNAME" would be quite flexible to
> > > configure a security policy for some binaries. This could also be
> > > protected by IMA/EVM, if needed.
> >
> > Checking for the existence of an xattr without caching is relatively
> > slow.  I'm not sure that we would want to go this route.
>  
> For identifying interpreters, xattrs would be too slow (without
> caching results), but once identified, using xattrs as you suggested,
> for specifying how interpreters can be invoked and limiting
> environment variables, is a good idea.  Perhaps the two xattrs could
> be combined?

It's not just #! you need to cover. If I can run ld.so for my arch format
then ld.so will helpfully let me load any ELF binary I like and run it.

Alan

\
 
 \ /
  Last update: 2017-06-14 16:11    [W:0.185 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site