i915 utils: range_overflows*()

[Kees Cook]

On Fri, May 30, 2025 at 10:44:31AM +0300, Jani Nikula wrote:
> 
> Hi Kees -
> 
> drivers/gpu/drm/i915/i915_utils.h has a handful of helper macros for
> checking range overflows: range_overflows(), range_overflows_t(),
> range_overflows_end(), and range_overflows_end_t().
> 
> Looks like the first one has also been copy-pasted to
> include/drm/drm_buddy.h.
> 
> Feels like include/linux/overflow.h would be the right place for (some
> version of) them.
> 
> Thoughts?

Sure, yes! They need some documentation too. :) And probably some
renaming. It looks like range_overflows() is not end-inclusive, but
range_overflows_end() is? And the _t variants are forcing explicit
types (like max_t, but unlike struct_size_t).

-- 
Kees Cook