Security Advisory

CVE-2026-43376

CVE vulnerability detail - eXtreme Datacenter Security Operations

Published 2026-05-08 14:21:25
Last updated 2026-05-23 16:06:52
Assigner Linux
CVSS score 9.8
State PUBLISHED

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free by using call_rcu() for oplock_info ksmbd currently frees oplock_info immediately using kfree(), even though it is accessed under RCU read-side critical sections in places like opinfo_get() and proc_show_files(). Since there is no RCU grace period delay between nullifying the pointer and freeing the memory, a reader can still access oplock_info structure after it has been freed. This can leads to a use-after-free especially in opinfo_get() where atomic_inc_not_zero() is called on already freed memory. Fix this by switching to deferred freeing using call_rcu().