On Thu, Jun 5, 2025 at 10:00 PM Andreas Hindborg <a.hindborg@xxxxxxxxxx> wrote: > > The current implementation of `ForeignOwnable` is leaking the type of the > opaque pointer to consumers of the API. This allows consumers of the opaque > pointer to rely on the information that can be extracted from the pointer > type. > > To prevent this, change the API to the version suggested by Maira > Canal (link below): Remove `ForeignOwnable::PointedTo` in favor of a > constant, which specifies the alignment of the pointers returned by > `into_foreign`. > > Suggested-by: Alice Ryhl <aliceryhl@xxxxxxxxxx> > Suggested-by: Maíra Canal <mcanal@xxxxxxxxxx> > Link: https://lore.kernel.org/r/20240309235927.168915-3-mcanal@xxxxxxxxxx > Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx> One nit below. With that and things other folks mentioned fixed, you may add: Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx> > diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs > index 22985b6f6982..025c619a2195 100644 > --- a/rust/kernel/types.rs > +++ b/rust/kernel/types.rs > @@ -21,15 +21,11 @@ > /// > /// # Safety > /// > -/// Implementers must ensure that [`into_foreign`] returns a pointer which meets the alignment > -/// requirements of [`PointedTo`]. > -/// > -/// [`into_foreign`]: Self::into_foreign > -/// [`PointedTo`]: Self::PointedTo > +/// Implementers must ensure that [`Self::into_foreign`] return pointers with alignment that is an > +/// integer multiple of [`Self::FOREIGN_ALIGN`]. We should require non-null: Implementers must ensure that [`Self::into_foreign`] returns pointers that are non-null and with alignment that is an integer multiple of [`Self::FOREIGN_ALIGN`]. Alice
