CVE-2026-64233CVE-2026-64233

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: hold opts->lock across XU walks in uvc_function_bind uvc_function_bind() walks &opts->extension_units twice without holding opts->lock: - directly, for the iExtension string-descriptor fixup loop; - indirectly, four times via uvc_copy_descriptors() (once per speed), where the helper iterates uvc->desc.extension_units (which aliases &opts->extension_units) to size and emit XU descriptors. The configfs side (uvcg_extension_make / uvcg_extension_drop, in drivers/usb/gadget/function/uvc_configfs.c) takes opts->lock around its list_add_tail / list_del operations. A privileged userspace process that holds the configfs subtree open and writes the gadget UDC name to bind the function while concurrently rmdir()'ing an extensions subdir can race uvcg_extension_drop() against the bind-time list walks and dereference a freed struct uvcg_extension. Hold opts->lock from the start of the XU string-