Re: [PATCH] mempool: Use kmalloc_size_roundup() to match ksize() usage

[Kees Cook]

On Tue, Oct 18, 2022 at 03:51:37PM -0700, Andrew Morton wrote:
> On Tue, 18 Oct 2022 02:03:29 -0700 Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> 
> > Round up allocations with kmalloc_size_roundup() so that mempool's use
> > of ksize() is always accurate and no special handling of the memory is
> > needed by KASAN, UBSAN_BOUNDS, nor FORTIFY_SOURCE.
> 
> Confused.  If the special handling is not needed, why doesn't the patch
> removed the no longer needed special handling?

The special handling is in the ksize() implementation, so it can't be
removed[1] until all the ksize()-affected users are updated to see their
true allocation sizes first.

[1] https://lore.kernel.org/lkml/20220923202822.2667581-16-keescook@xxxxxxxxxxxx/

-- 
Kees Cook