Bug 2559581 (CVE-2026-98908)

Summary:	CVE-2026-98908 kernel: net: microchip: sparx5: clean up PSFP resources on flower setup failure
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
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 Microchip Sparx5 network driver. When configuring traffic control rules with Per-Stream Filtering and Policing (PSFP), the driver fails to properly unwind allocated resources and correct reference counts if a setup step fails. A privileged local user could exploit this flaw by repeatedly triggering failed setup operations, causing a resource leak that may lead to 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 2026-10-23 12:13:47 UTC

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

net: microchip: sparx5: clean up PSFP resources on flower setup failure

sparx5_tc_flower_psfp_setup() allocates PSFP stream gate, flow meter and
stream filter resources before adding VCAP actions. If a later step
fails, the resources allocated earlier in the function are not unwound.

Add error paths to release the stream filter, flow meter and stream gate
when setup fails after they have been acquired.

Also make sparx5_psfp_fm_add() return the acquired flow-meter id before
the existing-flow-meter early return. When an existing flow meter is
reused, sparx5_psfp_fm_get() increments its pool reference count, but the
caller previously kept psfp_fmid as 0. If a later setup step failed, the
error path could try to delete flow-meter id 0 instead of the reused flow
meter, leaving the incremented reference behind.

Comment 1 Mauro Matteo Cascella 2026-10-26 18:26:23 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98908.mbox