Bug 2555250 (CVE-2026-98833)

Summary:	CVE-2026-98833 kernel: mtd: core: call _get_device() with the master MTD
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 Memory Technology Device (MTD) subsystem. When accessing certain partitions, the kernel improperly passes a partition device reference instead of the master device structure to the driver callback. A local user could exploit this flaw during device access operations to cause invalid memory references, resulting in a system crash and 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 2026-10-18 16:04:44 UTC

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

mtd: core: call _get_device() with the master MTD

__get_mtd_device() calls the master's _get_device() callback with mtd,
which may be a partition. __put_mtd_device() passes the master.

This breaks gluebi partitions because gluebi_get_device() uses
container_of() and therefore requires the master MTD. Pass the master
to _get_device(), matching _put_device().

Comment 1 Mauro Matteo Cascella 2026-10-23 21:03:23 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98833.mbox