CVE-2026-64456 hwrng: virtio: clamp device-reported used.len at copy_data()

In the Linux kernel, the following vulnerability has been resolved: hwrng: virtio: clamp device-reported used.len at copydata randomrecvdone stores the device-reported used.len directly into vi-dataavail. copydata then indexes vi-data using vi-dataidx advanced by previous copydata calls and issue...