[tor-dev] TBB Memory Allocator choice fingerprint implications

[teor]

Hi,

> On 18 Aug 2019, at 08:35, Shawn Webb <shawn.webb at hardenedbsd.org> wrote:
> 
> Having the heap implementation selectable at runtime would enable
> users to make the determination for themselves, while also making
> future integration efforts easier through modularization/abstraction
> APIs (I'm making a silly, naive, and likely wrong, assumption that such
> APIs don't already exist.)
> 
> I hope I'm not coming off as "hey, do this." I'm just thinking out
> loud in an admittedly naive fashion.
> 
> Anyone have any thoughts?

Allowing users to select the allocator at runtime would split the anonymity set, *if* the allocator was detectable remotely.

This is why we try to use safe defaults, and avoid user-selected options. When we do give users options, we create a few well-defined settings (like the security slider).

T