Deps.rs

slab_allocator 0.3.5

[![dependency status](https://deps.rs/crate/slab_allocator/0.3.5/status.svg)](https://deps.rs/crate/slab_allocator/0.3.5)

This project might be open to known security vulnerabilities, which can be prevented by tightening the version range of affected dependencies. Find detailed information at the bottom.

Crate slab_allocator

Dependencies

(2 total, 2 outdated, 2 possibly insecure)

CrateRequiredLatestStatus
 linked_list_allocator ⚠️^0.6.30.10.5out of date
 spin ⚠️^0.4.90.9.8out of date

Security Vulnerabilities

spin: Wrong memory orderings in RwLock potentially violates mutual exclusion

RUSTSEC-2019-0013

Wrong memory orderings inside the RwLock implementation allow for two writers to acquire the lock at the same time. The drop implementation used Ordering::Relaxed, which allows the compiler or CPU to reorder a mutable access on the locked data after the lock has been yielded.

Only users of the RwLock implementation are affected. Users of Once (including users of lazy_static with the spin_no_std feature enabled) are NOT affected.

On strongly ordered CPU architectures like x86, the only real way that this would lead to a memory corruption is if the compiler reorders an access after the lock is yielded, which is possible but in practice unlikely. It is a more serious issue on weakly ordered architectures such as ARM which, except in the presence of certain instructions, allow the hardware to decide which accesses are seen at what times. Therefore on an ARM system it is likely that using the wrong memory ordering would result in a memory corruption, even if the compiler itself doesn't reorder the memory accesses in a buggy way.

The flaw was corrected by https://github.com/mvdnes/spin-rs/pull/66.

linked_list_allocator: Multiple vulnerabilities resulting in out-of-bounds writes

RUSTSEC-2022-0063

  • The heap initialization methods were missing a minimum size check for the given heap size argument. This could lead to out-of-bound writes when a heap was initialized with a size smaller than 3 * size_of::<usize> because of metadata write operations.
  • When calling Heap::extend with a size smaller than two usizes (e.g., 16 on x86_64), the size was erroneously rounded up to the minimum size, which could result in an out-of-bounds write.
  • Calling Heap::extend on an empty heap tried to construct a heap starting at address 0, which is also an out-of-bounds write.
    • One specific way to trigger this accidentally is to call Heap::new (or a similar constructor) with a heap size that is smaller than two usizes. This was treated as an empty heap as well.
  • Calling Heap::extend on a heap whose size is not a multiple of the size of two usizes resulted in unaligned writes. It also left the heap in an unexpected state, which might lead to subsequent issues. We did not find a way to exploit this undefined behavior yet (apart from DoS on platforms that fault on unaligned writes).