rust: lockdep: Remove support for dynamically allocated LockClassKeys

commit 966944f3711665db13e214fef6d02982c49bb972 upstream.

Currently, dynamically allocated LockCLassKeys can be used from the Rust
side without having them registered. This is a soundness issue, so
remove them.

Fixes: 6ea5aa08857a ("rust: sync: introduce `LockClassKey`")
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Mitchell Levy <levymitchell0@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250307232717.1759087-11-boqun.feng@gmail.com
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mitchell Levy 2025-03-07 15:27:00 -08:00 committed by Greg Kroah-Hartman
parent 812080b01d
commit 50b22a98c1

View File

@ -26,11 +26,6 @@ pub struct LockClassKey(Opaque<bindings::lock_class_key>);
unsafe impl Sync for LockClassKey {}
impl LockClassKey {
/// Creates a new lock class key.
pub const fn new() -> Self {
Self(Opaque::uninit())
}
pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {
self.0.get()
}
@ -41,7 +36,10 @@ impl LockClassKey {
#[macro_export]
macro_rules! static_lock_class {
() => {{
static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new();
static CLASS: $crate::sync::LockClassKey =
// SAFETY: lockdep expects uninitialized memory when it's handed a statically allocated
// lock_class_key
unsafe { ::core::mem::MaybeUninit::uninit().assume_init() };
&CLASS
}};
}