Re: CVE-2014-4699: Linux ptrace bug

[Marc Deslauriers <marc.deslauriers () canonical com>]

On 14-07-05 05:22 PM, Yves-Alexis Perez wrote:
> On sam., 2014-07-05 at 22:25 +0400, Solar Designer wrote:
> > Here are some distro vendor status pages on this bug:
> >
> > "x86_64,ptrace: Enforce RIP <= TASK_SIZE_MAX (CVE-2014-4699)"
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1337339
> >
> > Ubuntu has just sent out 7 update announcements (for different of
> > their
> > supported distros/kernels), USN-2266-1 through USN-2272-1.
> >
> > "ptrace,x86: force IRET path after a ptrace_stop()"
> > http://kernel.opensuse.org/cgit/kernel/commit/?h=openSUSE-13.1&id=d1f26676dad578a65c94782f0c2bd00b7aa68f1b
> >
> > "CVE-2014-4699 Kernel: x86_64,ptrace: Enforce RIP <= TASK_SIZE_MAX"
> > https://bugzilla.redhat.com/show_bug.cgi?id=1115927
>
> Hmhm, what are the reasons why the mainline (and opensuse) fix
> (b9cd18de4db3c9ffa7e17b0dc0ca99ed5aa4d43a) is to force using IRET
> instead of SYSRET, while distros like Ubuntu and Redhat seem to “only”
> make sure RIP is canonical?
>
> Regards,

AFAIK, our plan is to switch to the upstream fix for the next kernel updates.

Marc.