CVE-2026-64419

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description Reading the debugfs count file of a memcg-aware shrinker can cause the system to sleep inside an RCU read-side critical section. This occurs because the shrinker debugfs count show() function invokes the count objects() callback while holding an RCU lock. Specifically, the zswap callback flushes memcg stats via the css rstat flush() function, which may sleep and therefore must not execute under RCU. RCU (Read-Copy-Update) is a synchronization mechanism that allows multiple readers to access data while it is being updated, but it prohibits sleeping in read-side critical sections to avoid system instability.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.