Re: [PATCH 1/2] rust: lockdep: Remove support for dynamically allocated LockClassKeys

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am 05.10.24 um 00:01 schrieb Mitchell Levy via B4 Relay:
From: Mitchell Levy <levymitchell0@xxxxxxxxx>

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

Suggested-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Link: https://lore.kernel.org/rust-for-linux/20240815074519.2684107-3-nmi@xxxxxxxxxxxx/
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mitchell Levy <levymitchell0@xxxxxxxxx>
---
  rust/kernel/lib.rs  |  2 +-
  rust/kernel/sync.rs | 14 ++------------
  2 files changed, 3 insertions(+), 13 deletions(-)

diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 22a3bfa5a9e9..b5f4b3ce6b48 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -44,8 +44,8 @@
  pub mod page;
  pub mod prelude;
  pub mod print;
-pub mod sizes;
  pub mod rbtree;
+pub mod sizes;
  mod static_assert;
  #[doc(hidden)]
  pub mod std_vendor;


This is fixed already

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/rust/kernel/lib.rs?id=ece207a83e464af710d641f29e32b7a144c48e79

and can be dropped here.


diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index 0ab20975a3b5..d270db9b9894 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -27,28 +27,18 @@
  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()
      }
  }
-impl Default for LockClassKey {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
  /// Defines a new static lock class and returns a pointer to it.
  #[doc(hidden)]
  #[macro_export]
  macro_rules! static_lock_class {
      () => {{
-        static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new();


Should the SAFETY comment added in the 2nd patch go to here?

+ // SAFETY: lockdep expects uninitialized memory when it's handed a statically allocated
+        // lock_class_key


+        static CLASS: $crate::sync::LockClassKey =
+            unsafe { ::core::mem::MaybeUninit::uninit().assume_init() };
          &CLASS
      }};
  }






[Index of Archives]     [Linux RAID]     [Linux SCSI]     [Linux ATA RAID]     [IDE]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Device Mapper]

  Powered by Linux