CVE-2026-68370 usb: gadget: dummy_hcd: prevent fifo_req reuse during giveback

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: dummyhcd: prevent fiforeq reuse during giveback dummyhcd embeds a single shared usbrequest dum-fiforeq that the "emulated single-request FIFO" fast-path in dummyqueue reuses for small IN transfers: it copies the...