Bug 2536507 (CVE-2026-90421)

Summary:	CVE-2026-90421 kernel: PCI: Fix UAF when probe runs concurrent to dyn ID removal
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:
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Doc Text:	A flaw was found in the Linux kernel's Peripheral Component Interconnect (PCI) subsystem. This Use-After-Free (UAF) vulnerability arises when a PCI device probe operation occurs concurrently with the removal of a dynamic ID. This timing issue could allow a local attacker to cause a system crash, leading to a denial of service, or potentially gain unauthorized access to sensitive information or execute arbitrary code.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-17 18:14:46 UTC

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

PCI: Fix UAF when probe runs concurrent to dyn ID removal

Dynamic IDs are only guaranteed to be valid when dynids.lock is held,
as remove_id_store() can free the node. Thus, make a copy in
pci_match_device(). Also, clarify that the id parameter is only valid
during probe.

Comment 1 gkamathe 2026-09-21 13:05:42 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90421.mbox