Re: [kernel-hardening] [PATCH] move RLIMIT_NPROC check from set_user() to do_execve_common()

Vasiliy Kulikov
2011-07-24T18:02:31Z

Solar,

On Sun, Jul 24, 2011 at 18:32 +0400, Solar Designer wrote:
> On Thu, Jul 21, 2011 at 04:48:30PM +0400, Solar Designer wrote:
> > Here's my current proposal:
> >
> > 1. Apply Vasiliy's patch to move the RLIMIT_NPROC check from setuid() to
> > execve(), optionally enhanced with setting PF_SETUSER_FAILED on
> > would-be-failed setuid() and checking this flag in execve() (in addition
> > to repeating the RLIMIT_NPROC check).
> >
> > 2. With a separate patch, add a prctl() to read the PF_SETUSER_FAILED flag.
> > Android will be able to use this if it wants to.
>
> Can you please implement these two patches and post them to LKML?
> (Include the PF_SETUSER_FAILED implementation in the first patch.)

I think (2) is too compicated. IIRC, application already may read
process flags via procfs. I'll prepare and test (1).

Thanks,

--
Vasiliy