Bug 2536582 (CVE-2026-90355)

Summary:	CVE-2026-90355 kernel: wifi: mt76: mt7996: clear stale link state on full reset
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:	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 Wi-Fi driver (mt76: mt7996) of the Linux kernel. After a full chip reset, the driver fails to properly clear stale link state information, causing the device to become inoperative. This issue arises because the system attempts to re-create device and station records while old link identifiers are still marked as valid. Furthermore, repeated full resets can lead to the exhaustion of Multi-Link Device (MLD) index space, preventing proper device functionality.	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 2026-09-17 18:31:35 UTC

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

wifi: mt76: mt7996: clear stale link state on full reset

After a full chip reset, mac80211 reconfig replays interface, link and
channel context setup. mt7996_vif_link_add() short-circuits when the
link_id is still marked in mvif->valid_links, a state introduced for
postponing link teardown to interface removal. The reset path frees the
link structures without clearing those bits, so the replayed setup never
re-creates dev_info/bss_info/STA records in the restarted firmware and
never re-registers the link wcid, leaving the device inoperative.

The reset path also leaks every allocated MLD index: per-link indices
and the per-vif group/remap indices are re-allocated from scratch during
reconfig, but the old bits stay set in the masks, so repeated full
resets exhaust the index space.

Clear valid_links in the reset vif iterator and reset the MLD index
masks alongside the existing omac_mask clearing.

Comment 1 gkamathe 2026-09-22 07:04:01 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90355.mbox