Bug 2535317 (CVE-2026-89817)

Summary: CVE-2026-89817 kernel: drm/gud: NUL-terminate TV mode names read from the device
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
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's drm/gud component. The `gud_connector_add_tv_mode()` function reads TV mode names from a USB device. These names are not guaranteed to be null-terminated, which can cause the system to read beyond the allocated buffer when processing them. This out-of-bounds read could lead to information disclosure or a denial of service.
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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 12:02:02 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/gud: NUL-terminate TV mode names read from the device

gud_connector_add_tv_mode() reads a buffer of fixed-size mode names from
the USB device and passes pointers into it to
drm_mode_create_tv_properties_legacy(), which calls strlen() on each one.
Nothing guarantees the device NUL-terminates a name, so strlen() can run
past the end of a slot and, for the last mode, past the end of the
allocation.

Terminate each name at the end of its slot before use.
Comment 1 gkamathe 2026-09-17 07:44:21 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89817.mbox