Re: [PATCH 0/2] maple_tree: Fix mas_prev() state regression.

From: Andrew Morton
Date: Thu Sep 21 2023 - 19:27:53 EST


On Thu, 21 Sep 2023 20:23:11 +0100 Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:

> > > It isn't clear what are the user-visible effects of this flaw? Please
> > > send this along and I'll paste it in.
> >
> >
> > User may notice that mas_prev() or mas_next() calls that result in going
> > outside of the limit passed to the call will cause incorrect returns on
> > subsequent calls using that maple state, such as mas_find() skipping an
> > entry.
>
> When Andrew says "User visible" he means "userspace visible". Not
> "in kernel user visible". What are the _consequences_.

Thanks ;)

We have a Link:
(https://gist.github.com/heatd/85d2971fae1501b55b6ea401fbbe485b) but it
takes us to the reproducer code. If it took us to Pedro's initial bug
report then the sun would shine and birds would sing.