lkml.org 
[lkml]   [2016]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] binfmt_misc: allow selecting the interpreter based on xattr keywords
On Fri, 26 Aug 2016 17:26:18 -0400
James Bottomley <James.Bottomley@HansenPartnership.com> wrote:

> On Fri, 2016-08-26 at 22:12 +0100, One Thousand Gnomes wrote:
> > > A non-security use case would be to run the binary (without
> > > modification) with a different ELF interpreter (assuming this
> > > allows to override binfmt_elf, but self-sandboxing would need that
> > > as well). This would make it easier to use older or newer libcs
> > > for select binaries on the system. Right now, one has to write
> > > wrappers for that, and the explicit dynamic linker invocation is
> > > not completely transparent to the application.
> >
> > If it gets in I'll be using it to label CP/M COM files so that they
> > can be auto-run nicely when crossbuilding stuff in part with the
> > original tools but a modern build environment 8)
> >
> > Sandboxing is an obvious use but there are more bizarre ones such as
> > marking a file system image to get auto-run under a virtual machine
> > or make containers fire up as if they were commands.
>
> So I asked previously but didn't get an answer. If this is useful for
> sandboxing and being in the sandbox depends on the xattr value,
> shouldn't it be in one of the privileged xattr namespaces, not the
> user. one?

IMHO no

- because it's not giving additional rights, it is taking rights away
voluntarily
- because as a user I can simply cp the file to get an unsandboxed version

If it was a setuid like bit then yes it would matter.

Alan

\
 
 \ /
  Last update: 2016-09-17 09:58    [W:0.053 / U:0.344 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site