Re: Re: Qualys Security Advisor -- The Stack Clash

[Jeff Law <law () redhat com>]

On 06/20/2017 12:44 AM, Daniel Micay wrote:

> I think it's also worth mentioning the segmented stack support in GCC
> and LLVM that was added for Go. It's possible to use it for C with the
> __morestack call set up to simply abort when stack space is exhausted.
>
> That's what Rust was doing after it dropped segmented stacks, but they
> wanted to move to stack probes for efficiency and prematurely dropped
> these function prelude checks.
>
> It's not efficient, but it works, unlike -fstack-check.
>
> I don't think it makes sense for general purpose distributions to adopt
> it but it's an available option for others with more concern about this
> issue.
Yup.  go's split-stacks are another option.  As you mention, probably
not performant enough for a general purpose distribution, but could be
interesting for more specialized needs.

jeff