Re: [PATCH] lib/string_helpers: rework overflow-dependent code

[Justin Stitt]

On Mon, Aug 12, 2024 at 11:44 AM Kees Cook <kees@xxxxxxxxxx> wrote:
>
> On Thu, 08 Aug 2024 14:43:56 -0700, Justin Stitt wrote:
> > When @size is 0, the desired behavior is to allow unlimited bytes to be
> > parsed. Currently, this relies on some intentional arithmetic overflow
> > where --size gives us SIZE_MAX when size is 0.
> >
> > Explicitly spell out the desired behavior without relying on intentional
> > overflow/underflow.
> >
> > [...]
>
> Since we can't have allocations larger than INT_MAX, SIZE_MAX is
> sufficiently large for this use-case, and the "off by one" introduce
> here isn't meaningful. I prefer the improved readability and lack of
> wrapping pre-decrement.

Great! Thanks.

>
> Applied to for-next/hardening, thanks!
>
> [1/1] lib/string_helpers: rework overflow-dependent code
>       https://git.kernel.org/kees/c/5d6b91b74ccd
>
> Take care,
>
> --
> Kees Cook
>