Bug 2482600 (CVE-2026-46137)

Summary:	CVE-2026-46137 kernel: mptcp: pm: ADD_ADDR rtx: fix potential data-race
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:	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 Linux kernel, specifically within the Multipath TCP (MPTCP) implementation. The mptcp_pm_add_timer() helper, which is executed as a timer callback, does not properly hold the socket lock when operating in a softirq context. This oversight can lead to a potential data race, which may result in unpredictable system behavior or instability.	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 2026-05-28 11:05:14 UTC

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

mptcp: pm: ADD_ADDR rtx: fix potential data-race

This mptcp_pm_add_timer() helper is executed as a timer callback in
softirq context. To avoid any data races, the socket lock needs to be
held with bh_lock_sock().

If the socket is in use, retry again soon after, similar to what is done
with the keepalive timer.

Comment 1 Keith Grant 2026-05-28 17:06:56 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052819-CVE-2026-46137-eb9d@gregkh/T