lkml.org 
[lkml]   [2012]   [Mar]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] futex: do not leak robust list to unprivileged process
On Wed, 28 Mar 2012, Kees Cook wrote:

> On Thu, Mar 22, 2012 at 4:46 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
> > On Tue, 20 Mar 2012, Ingo Molnar wrote:
> >> * Kees Cook <keescook@chromium.org> wrote:
> >> > On Tue, Mar 20, 2012 at 10:02 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> >> > > I really wonder why we have this syscall at all.
> >> >
> >> > The documentation I found yesterday while looking at this was:
> >> > http://linux.die.net/man/2/get_robust_list
> >> >
> >> > Which says "The system call is only available for debugging
> >> > purposes and is not needed for normal operations. Both system
> >> > calls are not available to application programs as functions;
> >> > they can be called using the syscall(3) function."
> >> >
> >> > Dropping the syscall entirely would certainly make it secure.
> >> > ;)
> >>
> >> The thinking was API completeness. In general it's possible for
> >> a sufficiently privileged task to figure out all the state of a
> >> task. We can query timers, fds - the robust list is such a
> >> resource as well. The information leakage was obviously not
> >> intended.
> >
> > So I think it's safe to take Kees' patch as is. On top of that we
> > should add a WARN_ONCE when the syscall is invoked and schedule the
> > sucker for removal.
>
> Can someone claim the first patch? It looks like not everyone agrees
> about removal, but I'd like to see at least the first one get in. :)

It's on my list for tomorrow.


\
 
 \ /
  Last update: 2012-03-28 23:27    [W:0.114 / U:1.932 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site