Bug 2535322 (CVE-2026-90045)

Summary:	CVE-2026-90045 kernel: USB: gadget: ffs: fix mm lifetime handling
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 USB gadget functionfs (ffs) component. This vulnerability occurs because the `io_data` structure does not properly manage the lifetime of memory references during asynchronous requests. A local attacker could exploit this by causing a task to exit prematurely, leading to a use-after-free condition. This could result in a denial of service or potentially lead to arbitrary code execution.	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 12:02:48 UTC

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

USB: gadget: ffs: fix mm lifetime handling

io_data stores a pointer to the submitting task's mm_struct,
but does not currently hold a reference to it while async
requests are pending.

This can result in a use-after-free if the task exits before
completion handling finishes.

Take a reference with mmgrab() when queuing the read request
and release it with mmdrop() on request completion.

Comment 1 gkamathe 2026-09-17 08:38:29 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90045.mbox