Bug 2536789 (CVE-2026-90425)

Summary:	CVE-2026-90425 kernel: iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID
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, specifically within the IOMMU (Input/Output Memory Management Unit) Tegra241 command queue driver. This vulnerability arises from improper handling of virtual Stream IDs (vSID) when a device has either multiple or no physical Stream IDs. A malicious guest operating system could exploit this to trigger an out-of-bounds read, which may lead to a system crash (Denial of Service) or the disclosure of sensitive information.	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 19:33:51 UTC

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

iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID

tegra241_vintf_init_vsid() maps a guest vSID to a single physical Stream ID
taken from master->streams[0], and only warns when the device does not have
exactly one stream. A device with several streams gets only its first one
mapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB
entries; a device with none makes master->streams a ZERO_SIZE_PTR, read out
of bounds.

Reject the mapping with -EOPNOTSUPP if master->num_streams is not one.

Comment 1 gkamathe 2026-09-21 13:48:00 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90425.mbox