Bug 2388956 (CVE-2023-32246)

Summary: CVE-2023-32246 kernel: ksmbd: call rcu_barrier() in ksmbd_server_exit()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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Description OSIDB Bzimport 2025-08-16 14:01:12 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ksmbd: call rcu_barrier() in ksmbd_server_exit()

racy issue is triggered the bug by racing between closing a connection
and rmmod. In ksmbd, rcu_barrier() is not called at module unload time,
so nothing prevents ksmbd from getting unloaded while it still has RCU
callbacks pending. It leads to trigger unintended execution of kernel
code locally and use to defeat protections such as Kernel Lockdown
Comment 1 Vipul Nair 2025-08-18 05:44:29 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025081612-CVE-2023-32246-2e6d@gregkh/T