Array::insert violates exception safety if compare function panics, leading to potential Double-Free
In affected versions of this crate, Array::insert is not exception safe. In the UPSERT path, key and value's snapshot is written to self.data_block, and after the insertion is completed, key and value are mem::forget in order to prevent double free. However, during the insertion, K::compare is invoked, which is a user-provided method. If user deliberately call panic in this function, during unwinding, the destructors of key, value, and self will all be called (since the mem::forget has not been called yet), leading to Double Free. Similar issues happens in the !UPSERT path.
The soundness issue was fixed in version 3.8.4 by using ManuallyDrop instead of mem::forget, and separating fallible code from infallible code during a node split - insert = insert_try -> insert_unchecked.
See advisory page for additional details.
scc2.4.0In affected versions of this crate,
Array::insertis not exception safe. In theUPSERTpath,keyandvalue's snapshot is written toself.data_block, and after the insertion is completed,keyandvaluearemem::forgetin order to prevent double free. However, during the insertion,K::compareis invoked, which is a user-provided method. If user deliberately call panic in this function, during unwinding, the destructors ofkey,value, andselfwill all be called (since themem::forgethas not been called yet), leading to Double Free. Similar issues happens in the!UPSERTpath.The soundness issue was fixed in version
3.8.4by usingManuallyDropinstead ofmem::forget, and separating fallible code from infallible code during a node split - insert = insert_try -> insert_unchecked.See advisory page for additional details.