Bug 2535201 (CVE-2026-90020)

Summary:	CVE-2026-90020 kernel: USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl()
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
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 USB gadget subsystem. A race condition in the `gadget_dev_ioctl()` function, where a pointer is read before a lock is acquired, can lead to a null pointer dereference. A local attacker could exploit this timing issue during a concurrent bind operation, potentially causing a system crash and leading to a denial of service.	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 2026-09-16 11:25:53 UTC

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

USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl()

gadget_dev_ioctl() reads dev->gadget before acquiring dev->lock, but
dev->state is checked after acquiring the lock. Therefore a concurrent
bind can change the device state between these operations, which can
leave ioctl with a stale NULL gadget pointer and causing a NULL pointer
dereference at gadget->ops->ioctl.

Read dev->gadget while holding dev->lock so that the gadget pointer
and device state are sampled consistently.

Comment 1 Keith Grant 2026-09-16 23:17:13 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90020.mbox