Bug 2535191 (CVE-2026-90019)

Summary: CVE-2026-90019 kernel: usb: gadget: fix null pointer dereference in usb_put_function_instance()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: 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   
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Doc Text:
A flaw was found in the Linux kernel. A null pointer dereference can occur in the `usb_put_function_instance()` function within the USB gadget subsystem. This issue arises because a file descriptor (`fd`) is not allocated before being dereferenced in an error path, which can lead to a system crash. A local attacker could exploit this vulnerability to cause a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-16 11:19:54 UTC 
In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: fix null pointer dereference in usb_put_function_instance()

usb_put_function_instance() attempts to dereference fd inside fi struct
to get mod in uvc_alloc_inst() error path. However, fd is not allocated
until later in try_get_usb_function_instance() after allocating fi in
uvc_alloc_inst() and thus guranteed to be null in error path. Fix this
by adding a null check for fi->fd that returns if fd is null.
Comment 1 Keith Grant 2026-09-16 23:13:41 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90019.mbox