DeliverRawEvent(RawDeviceEvent *ev, DeviceIntPtr device)
{
    GrabPtr grab = device->deviceGrab.grab;
    xEvent *xi;
    int i, rc;
    int filter;

    rc = EventToXI2((InternalEvent *) ev, (xEvent **) &xi);
    if (rc != Success) {
        ErrorF("[Xi] %s: XI2 conversion failed in %s (%d)\n",
               __func__, device->name, rc);
        return;
    }

    if (grab)
        DeliverGrabbedEvent((InternalEvent *) ev, device, FALSE);

    filter = GetEventFilter(device, xi);

    for (i = 0; i < screenInfo.numScreens; i++) {
        WindowPtr root;
        InputClients *inputclients;

        root = screenInfo.screens[i]->root;
        if (!GetClientsForDelivery(device, root, xi, filter, &inputclients))
            continue;

        for (; inputclients; inputclients = inputclients->next) {
            ClientPtr c;        /* unused */
            Mask m;             /* unused */
            InputClients ic = *inputclients;

            /* Because we run through the list manually, copy the actual
             * list, shorten the copy to only have one client and then pass
             * that down to DeliverEventToInputClients. This way we avoid
             * double events on XI 2.1 clients that have a grab on the
             * device.
             */
            ic.next = NULL;

            if (!FilterRawEvents(rClient(&ic), grab, root))
                DeliverEventToInputClients(device, &ic, root, xi, 1,
                                           filter, NULL, &c, &m);
        }
    }

    free(xi);
}

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.