[PATCH 2/2] kasan: apply store-only mode in kasan kunit testcases

[Andrey Konovalov]

On Tue, Aug 12, 2025 at 6:57 PM Yeoreum Yun <yeoreum.yun at arm.com> wrote:
>
> > Right now, KASAN tests are crafted to avoid/self-contain harmful
> > memory corruptions that they do (e.g. make sure that OOB write
> > accesses land in in-object kmalloc training space, etc.). If you turn
> > read accesses in tests into write accesses, memory corruptions caused
> > by the earlier tests will crash the kernel or the latter tests.
>
> That's why I run the store-only test when this mode is "sync"
> In case of "async/asymm" as you mention since it reports "after",
> there will be memory corruption.
>
> But in case of sync, when the MTE fault happens, it doesn't
> write to memory so, I think it's fine.

Does it not? I thought MTE gets disabled and we return from the fault
handler and let the write instruction execute. But my memory on this
is foggy. And I don't have a setup right now to test.