Bug 2393162 (CVE-2025-38717)

Summary: CVE-2025-38717 kernel: net: kcm: Fix race condition in kcm_unattach()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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OS: Linux   
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Description OSIDB Bzimport 2025-09-04 16:01:55 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: kcm: Fix race condition in kcm_unattach()

syzbot found a race condition when kcm_unattach(psock)
and kcm_release(kcm) are executed at the same time.

kcm_unattach() is missing a check of the flag
kcm->tx_stopped before calling queue_work().

If the kcm has a reserved psock, kcm_unattach() might get executed
between cancel_work_sync() and unreserve_psock() in kcm_release(),
requeuing kcm->tx_work right before kcm gets freed in kcm_done().

Remove kcm->tx_stopped and replace it by the less
error-prone disable_work_sync().
Comment 1 Jon Moroney 2025-09-04 19:59:23 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025090459-CVE-2025-38717-fbf6@gregkh/T