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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 5 Jul 2017 16:55:16 -0700
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Subject: Re: [PATCH] mm: larger stack guard gap, between vmas
To: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>, Michal Hocko <mhocko@kernel.org>,
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On Wed, Jul 5, 2017 at 4:50 PM, Kees Cook <keescook@chromium.org> wrote:
>
> As part of that should we put restrictions on the environment of
> set*id exec too?

I'm not seeing what sane limits you could use.

I think the concept of "reset as much of the environment to sane
things when running suid binaries" is a good concepr.

But we simply don't have any sane values to reset things to.

                Linus