On 07/29/2015 12:06 AM, Paul Eggert wrote:
> Daniel Colascione wrote:
>> What's wrong with just mprotecting a guard page at the end of the stack,
>> and on overflow, giving that region normal protection, unwinding as
>> normal, then, at top level, restoring the guard page?
> 
> Unwinding can grow the stack.

Sure. That's why you open up more stack to do the unwinding. Having done
that, if you still overflow, just abort. At that point, you can't
guarantee correct program semantics.