Bug 2418819 (CVE-2025-40242)

Summary: CVE-2025-40242 kernel: gfs2: Fix unlikely race in gdlm_put_lock
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
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 2025-12-04 16:02:12 UTC 
In the Linux kernel, the following vulnerability has been resolved:

gfs2: Fix unlikely race in gdlm_put_lock

In gdlm_put_lock(), there is a small window of time in which the
DFL_UNMOUNT flag has been set but the lockspace hasn't been released,
yet.  In that window, dlm may still call gdlm_ast() and gdlm_bast().
To prevent it from dereferencing freed glock objects, only free the
glock if the lockspace has actually been released.
Comment 1 Alexander B 2025-12-05 16:31:39 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025120403-CVE-2025-40242-8f73@gregkh/T