Bug 2525468 (CVE-2026-80715)

Summary:	CVE-2026-80715 kernel: igc: remove napi_synchronize() in igc_down()
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:	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's igc network driver. When an application using AF_XDP, a high-performance network data path, is abruptly terminated, a synchronization issue can occur. This prevents the network interface from properly shutting down. A local attacker could exploit this to cause a Denial of Service (DoS) by making the system unresponsive.	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 2026-08-28 07:46:31 UTC

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

igc: remove napi_synchronize() in igc_down()

When an AF_XDP zero-copy application is killed abruptly, the XSK pool is
torn down but NAPI keeps polling. igc_clean_rx_irq_zc() then returns the
full budget on every poll, so napi_complete_done() never clears
NAPI_STATE_SCHED.

igc_down() calls napi_synchronize() before napi_disable(), so it spins
forever waiting for that bit and the interface never goes down. Drop the
napi_synchronize() and let napi_disable() do the job -- it sets
NAPI_STATE_DISABLE, which forces the stuck poll to complete. Reorder it
ahead of igc_set_queue_napi() so the NAPI mapping is cleared only after
polling has stopped, matching the recent igb fix b1e067240379.

Comment 1 gkamathe 2026-09-01 07:10:20 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026082809-CVE-2026-80715-1a74@gregkh/T