The `#[pin_data]` macro uses some auxiliary traits to ensure that a user
does not implement `Drop` for the annotated struct, as that is unsound
and can lead to UB. However, if the struct that is annotated is
`!Sized`, the current bounds do not work, because `Sized` is an implicit
bound for generics.
This is *not* a soundness hole of pin-init, as it currently is
impossible to construct an unsized struct using pin-init.
Signed-off-by: Benno Lossin <lossin@kernel.org>
---
Changes in v2: none
---
rust/pin-init/internal/src/pin_data.rs | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/rust/pin-init/internal/src/pin_data.rs b/rust/pin-init/internal/src/pin_data.rs
index 3211fb522330..b35953b2daaa 100644
--- a/rust/pin-init/internal/src/pin_data.rs
+++ b/rust/pin-init/internal/src/pin_data.rs
@@ -228,7 +228,7 @@ fn drop(&mut self) {
// if it also implements `Drop`
trait MustNotImplDrop {}
#[expect(drop_bounds)]
- impl<T: ::core::ops::Drop> MustNotImplDrop for T {}
+ impl<T: ::core::ops::Drop + ?::core::marker::Sized> MustNotImplDrop for T {}
impl #impl_generics MustNotImplDrop for #ident #ty_generics
#whr
{}
@@ -237,7 +237,7 @@ impl #impl_generics MustNotImplDrop for #ident #ty_generics
// `PinnedDrop` as the parameter to `#[pin_data]`.
#[expect(non_camel_case_types)]
trait UselessPinnedDropImpl_you_need_to_specify_PinnedDrop {}
- impl<T: ::pin_init::PinnedDrop>
+ impl<T: ::pin_init::PinnedDrop + ?::core::marker::Sized>
UselessPinnedDropImpl_you_need_to_specify_PinnedDrop for T {}
impl #impl_generics
UselessPinnedDropImpl_you_need_to_specify_PinnedDrop for #ident #ty_generics
--
2.52.0