Re: [PATCH RFC] mm: protect suid binaries against rowhammer with copy-on-read mappings

From: Kirill A. Shutemov
Date: Wed Mar 18 2015 - 05:57:57 EST


On Wed, Mar 18, 2015 at 11:30:40AM +0300, Konstantin Khlebnikov wrote:
> From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
>
> Each user gets private copy of the code thus nobody will be able to exploit
> pages in the page cache. This works for statically-linked binaries. Shared
> libraries are still vulnerable, but setting suid bit will protect them too.

Hm. Do we have suid/sgid semantic defiend for non-executables?

To me we should do this for all file private mappings of the suid process
or don't do it at all.

And what about forked suid process which dropped privilages. We still have
code pages shared.

I don't think it worth it. The only right way to fix the problem is ECC
memory.

--
Kirill A. Shutemov
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