Bug 2540559 (CVE-2026-97434)

Summary:	CVE-2026-97434 kernel: dpaa2-switch: fix handling of NAPI on the remove path
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 dpaa2-switch network driver. During device removal, network packet polling instances (NAPI) shared across switch ports can be deleted before they are properly disabled. A local user with administrative privileges could trigger this issue during device teardown, potentially leading to kernel instability and a denial of service (system crash).	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-24 17:14:55 UTC

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

dpaa2-switch: fix handling of NAPI on the remove path

All the NAPI instances for a DPSW device are attached to the first
switch port's net_device but shared by all ports. The NAPI instances get
disabled only once the last port goes down.

This causes an issue on the .remove() path where each port is
unregistered and freed one at a time, causing the NAPI instances to be
deleted even though they are not disabled.

In order to avoid this, split up the unregister_netdev() calls from the
free_netdev() so that we make sure all ports go down before we attempt
a deletion of NAPI instances. Also, make the netif_napi_del() explicit
as it is on the .probe() path.

Comment 1 Mauro Matteo Cascella 2026-09-29 13:32:27 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97434.mbox