Bug 2541318 (CVE-2026-98112)

Summary:	CVE-2026-98112 kernel: ksmbd: fix listener task lifetime on netdev events
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
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Doc Text:	A flaw was found in the Linux kernel's ksmbd module. When handling network device events or connection teardown, a timing issue allows a background listener task to be freed before it is properly stopped, resulting in a use-after-free condition. A local attacker capable of triggering network interface state changes could exploit this vulnerability to crash the system, leading to a Denial of Service (DoS).	Story Points:	---
Clone Of:		Environment:
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-25 11:22:54 UTC

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix listener task lifetime on netdev events

The listener thread exits when its listening socket is shutdown. The
netdevice notifier shuts down the socket before calling kthread_stop(), so
the task_struct can be freed before kthread_stop() gets its reference.

Create the listener in a stopped state and hold an extra task_struct
reference until kthread_stop_put() completes. Also stop and release
listeners before freeing their interface records during TCP teardown.

Comment 1 Keith Grant 2026-09-28 12:31:31 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98112.mbox