CheckMotion(DeviceEvent *ev, DeviceIntPtr pDev)
{
    WindowPtr prevSpriteWin, newSpriteWin;
    SpritePtr pSprite = pDev->spriteInfo->sprite;

    verify_internal_event((InternalEvent *) ev);

    prevSpriteWin = pSprite->win;

    if (ev && !syncEvents.playingEvents) {
        /* GetPointerEvents() guarantees that pointer events have the correct
           rootX/Y set already. */
        switch (ev->type) {
        case ET_ButtonPress:
        case ET_ButtonRelease:
        case ET_Motion:
        case ET_TouchBegin:
        case ET_TouchUpdate:
        case ET_TouchEnd:
            break;
        default:
            /* all other events return FALSE */
            return FALSE;
        }

#ifdef PANORAMIX
        if (!noPanoramiXExtension) {
            /* Motion events entering DIX get translated to Screen 0
               coordinates.  Replayed events have already been
               translated since they've entered DIX before */
            ev->root_x += pSprite->screen->x - screenInfo.screens[0]->x;
            ev->root_y += pSprite->screen->y - screenInfo.screens[0]->y;
        }
        else
#endif
        {
            if (pSprite->hot.pScreen != pSprite->hotPhys.pScreen) {
                pSprite->hot.pScreen = pSprite->hotPhys.pScreen;
                RootWindow(pDev->spriteInfo->sprite) =
                    pSprite->hot.pScreen->root;
            }
        }

        pSprite->hot.x = ev->root_x;
        pSprite->hot.y = ev->root_y;
        if (pSprite->hot.x < pSprite->physLimits.x1)
            pSprite->hot.x = pSprite->physLimits.x1;
        else if (pSprite->hot.x >= pSprite->physLimits.x2)
            pSprite->hot.x = pSprite->physLimits.x2 - 1;
        if (pSprite->hot.y < pSprite->physLimits.y1)
            pSprite->hot.y = pSprite->physLimits.y1;
        else if (pSprite->hot.y >= pSprite->physLimits.y2)
            pSprite->hot.y = pSprite->physLimits.y2 - 1;
        if (pSprite->hotShape)
            ConfineToShape(pDev, pSprite->hotShape, &pSprite->hot.x,
                           &pSprite->hot.y);
        pSprite->hotPhys = pSprite->hot;

        if ((pSprite->hotPhys.x != ev->root_x) ||
            (pSprite->hotPhys.y != ev->root_y)) {
#ifdef PANORAMIX
            if (!noPanoramiXExtension) {
                XineramaSetCursorPosition(pDev, pSprite->hotPhys.x,
                                          pSprite->hotPhys.y, FALSE);
            }
            else
#endif
            {
                (*pSprite->hotPhys.pScreen->SetCursorPosition) (pDev,
                                                                pSprite->
                                                                hotPhys.pScreen,
                                                                pSprite->
                                                                hotPhys.x,
                                                                pSprite->
                                                                hotPhys.y,
                                                                FALSE);
            }
        }

        ev->root_x = pSprite->hot.x;
        ev->root_y = pSprite->hot.y;
    }

    newSpriteWin = XYToWindow(pSprite, pSprite->hot.x, pSprite->hot.y);

    if (newSpriteWin != prevSpriteWin) {
        int sourceid;

        if (!ev) {
            UpdateCurrentTimeIf();
            sourceid = pDev->id;        /* when from WindowsRestructured */
        }
        else
            sourceid = ev->sourceid;

        if (prevSpriteWin != NullWindow) {
            if (!ActivateEnterGrab(pDev, prevSpriteWin, newSpriteWin))
                DoEnterLeaveEvents(pDev, sourceid, prevSpriteWin,
                                   newSpriteWin, NotifyNormal);
        }
        /* set pSprite->win after ActivateEnterGrab, otherwise
           sprite window == grab_window and no enter/leave events are
           sent. */
        pSprite->win = newSpriteWin;
        PostNewCursor(pDev);
        return FALSE;
    }
    return TRUE;
}

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.