iOS/macOS - Out-of-Bounds Timestamp Write in IOAccelCommandQueue2::processSegmentKernelCommand()

While investigating possible shared memory issues in AGXCommandQueue::processSegmentKernelCommand, I noticed that the size checks used to parse the IOAccelKernelCommand in IOAccelCommandQueue2::processSegmentKernelCommand are incorrect. The IOAccelKernelCommand contains an 8-byte header consistin...