Messages in this thread | | | Date | Wed, 03 Jun 2009 12:36:25 -0400 | From | Rik van Riel <> | Subject | Re: Security fix for remapping of page 0 (was [PATCH] Change ZERO_SIZE_PTR to point at unmapped space) |
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Larry H. wrote:
> Christopher, crippling the system is truly not the way to fix this. > There are many legitimate users of private|fixed mappings at 0. In > addition, if you want to go ahead and break POSIX, at least make sure > your patch closes the loophole.
I suspect there aren't many at all, and restricting them through SELinux may be enough to mitigate the risk.
> If SELinux isn't present, that's not useful. If mmap_min_addr is > enabled, that still won't solve what my original, utterly simple patch > fixes.
Would anybody paranoid run their system without SELinux?
> The patch provides a no-impact, clean solution to prevent kmalloc(0) > situations from becoming a security hazard. Nothing else.
True, the changes in your patch only affect a few code paths.
-- All rights reversed.
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