Bug 2546365 (CVE-2026-98327)

Summary:	CVE-2026-98327 kernel: wifi: mac80211: mesh: reset the CSA state when leaving
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:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's mac80211 wireless mesh networking subsystem. When leaving or stopping a mesh network while a Channel Switch Announcement (CSA) is still pending, the kernel fails to reset the switch state and release allocated memory. A local privileged user could exploit this flaw to cause memory leaks and state inconsistency, potentially resulting in a Denial of Service (DoS).	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 2026-10-06 09:06:47 UTC

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

wifi: mac80211: mesh: reset the CSA state when leaving

ifmsh->csa is allocated in ieee80211_mesh_csa_beacon() and only freed
in ieee80211_mesh_finish_csa(), i.e. when the channel switch completes.
Leaving the mesh while a switch is still pending therefore leaks it.

Additionally, ifmsh->csa_role and ifmsh->chsw_ttl have their state leak
in this case, so things can get mixed up in addition to the memory
leak.

Refactor the reset and call it in ieee80211_stop_mesh() to fix it all.

Comment 1 gkamathe 2026-10-10 08:44:55 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98327.mbox