static uint64_t cirrus_mmio_read(void *opaque, hwaddr addr,
                                 unsigned size)
{
    CirrusVGAState *s = opaque;

    if (addr >= 0x100) {
        return cirrus_mmio_blt_read(s, addr - 0x100);
    } else {
        return cirrus_vga_ioport_read(s, addr + 0x10, size);
    }
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.