CVE-2026-53170 accel/ethosu: reject DMA commands with uninitialized length

In the Linux kernel, the following vulnerability has been resolved: accel/ethosu: reject DMA commands with uninitialized length cmdstateinit initializes the command state with memset0xff, leaving dma-len at U64MAX to signal missing setup. The only setter is NPUSETDMA0LEN; if userspace omits this...