Bug 2513421 (CVE-2026-68153)

Summary:	CVE-2026-68153 kernel: libceph: remove debugfs files before client teardown
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's libceph component. During the process of tearing down a client, the monitor client is stopped before its associated debugfs files are removed. This timing issue allows a concurrent read of the `monmap` debugfs file to access memory that has already been freed, leading to a use-after-free vulnerability. This type of flaw can potentially lead to system instability or a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-08-10 12:36:23 UTC

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

libceph: remove debugfs files before client teardown

ceph_destroy_client() tears down the monitor client before removing
the per-client debugfs files. A concurrent read of the monmap debugfs
file can enter monmap_show() after ceph_monc_stop() has freed
monc->monmap, triggering a use-after-free.

Remove the debugfs files before stopping the OSD and monitor clients.
debugfs_remove() drains active handlers and prevents new accesses, so
the debugfs callbacks can no longer race the rest of client teardown.

Comment 1 Mauro Matteo Cascella 2026-08-11 14:12:33 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081002-CVE-2026-68153-55a7@gregkh/T