With its original introduction, GNTTAB_cache_flush was made available uniformly. XSA-232 (CVE-2017-14318) then covered an omitted NULL pointer check, yet the addition of that check failed to adjust the subsequent error path. That error path fails to drop a page reference in case the specified page is owned by a special system domain (DOM_IO and DOM_COW are system domains which can have memory pages assigned to them.)
Weakness
The product does not release or incorrectly releases a resource before it is made available for re-use.
Potential Mitigations
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, languages such as Java, Ruby, and Lisp perform automatic garbage collection that releases memory for objects that have been deallocated.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/125.html
- https://cwe.mitre.org/data/definitions/130.html
- https://cwe.mitre.org/data/definitions/131.html
- https://cwe.mitre.org/data/definitions/494.html
- https://cwe.mitre.org/data/definitions/495.html
- https://cwe.mitre.org/data/definitions/496.html
- https://cwe.mitre.org/data/definitions/666.html