Re: [PATCH v2 1/1] mseal: update mseal.rst

[Jeff Xu <jeffxu@chromium.org>]

Hi Randy

On Fri, Oct 4, 2024 at 4:52 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>
>
>
> On 10/4/24 9:52 AM, Jeff Xu wrote:
> >> above is not a sentence but I don't know how to fix it.
> >>
> > Would below work ?
> >
> > Certain destructive madvise behaviors, specifically MADV_DONTNEED,
> > MADV_FREE, MADV_DONTNEED_LOCKED, MADV_FREE, MADV_DONTFORK,
> > MADV_WIPEONFORK, can pose risks when applied to anonymous memory by
> > threads without write permissions. These behaviors have the potential
> > to modify region contents by discarding pages, effectively performing
> > a memset(0) operation on the anonymous memory.
>
> Yes, that works.
> Or at least it explains the problem, like Theo said.
>
I updated with :

Certain destructive madvise behaviors, specifically MADV_DONTNEED,
MADV_FREE, MADV_DONTNEED_LOCKED, and MADV_WIPEONFORK, can introduce
risks when applied to anonymous memory by threads lacking write
permissions. Consequently, these operations are prohibited under such
conditions. The aforementioned behaviors have the potential to modify
region contents by discarding pages, effectively performing a
memset(0) operation on the anonymous memory.

Thanks
-Jeff



> Thanks.
> --
> ~Randy