Bug 2461447 (CVE-2026-31639)

Summary:	CVE-2026-31639 kernel: rxrpc: Fix key reference count leak from call->key
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the rxrpc subsystem of the Linux kernel. When a client call is created, a reference to a key is obtained but not properly released when the call is destroyed. This oversight leads to a key reference count leak, which can accumulate over time. This resource exhaustion could eventually allow a local attacker to cause a Denial of Service (DoS) by consuming available system resources.	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 2026-04-24 15:02:00 UTC

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

rxrpc: Fix key reference count leak from call->key

When creating a client call in rxrpc_alloc_client_call(), the code obtains
a reference to the key.  This is never cleaned up and gets leaked when the
call is destroyed.

Fix this by freeing call->key in rxrpc_destroy_call().

Before the patch, it shows the key reference counter elevated:

$ cat /proc/keys | grep afs@54321
1bffe9cd I--Q--i 8053480 4169w 3b010000  1000  1000 rxrpc     afs@54321: ka
$

After the patch, the invalidated key is removed when the code exits:

$ cat /proc/keys | grep afs@54321
$

Comment 1 Keith Grant 2026-04-24 21:19:15 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026042456-CVE-2026-31639-ef94@gregkh/T