Re: [PATCH 0/2] Fatal signal handing within uaccess faults

From: Mark Rutland
Date: Tue Jul 11 2017 - 11:12:05 EST


On Tue, Jul 11, 2017 at 08:04:50AM -0700, Andy Lutomirski wrote:
> On Tue, Jul 11, 2017 at 7:16 AM, Mark Rutland <mark.rutland@xxxxxxx> wrote:
> > Hi,
> >
> > Arch maintainer tl;dr: most arch fault code doesn't handle fatal signals
> > correctly, allowing unprivileged users to create an unkillable task which can
> > lock up the system. Please check whether your arch is affected.
>
> I haven't tested for real, but brief inspection of the code suggests
> that x86 is okay.

AFAICT, yes.

As mentioned later on in the message, I beleive it's been ok since
commit:

26178ec11ef3c6c8 ("x86: mm: consolidate VM_FAULT_RETRY handling")

... and my test-case didn't trigger anything in local testing on my
desktop.

Mark.