Am Montag, den 21.09.2009, 06:09 +0200 schrieb Markus Rechberger:
> On Mon, Sep 21, 2009 at 5:46 AM, hermann pitton <hermann-pitton@xxxxxxxx> wrote:
> >
> > Am Montag, den 21.09.2009, 05:40 +0200 schrieb Markus Rechberger:
> >> while porting the S2api to userspace I came accross the S2-API definition itself
> >>
> >> #define FE_SET_PROPERTY _IOW('o', 82, struct dtv_properties)
> >> #define FE_GET_PROPERTY _IOR('o', 83, struct dtv_properties)
> >>
> >> while looking at this, FE_GET_PROPERTY should very likely be _IOWR
> >>
> >> in dvb-frontend.c:
> >> ----
> >> if(cmd == FE_GET_PROPERTY) {
> >>
> >> tvps = (struct dtv_properties __user *)parg;
> >>
> >> dprintk("%s() properties.num = %d\n", __func__, tvps->num);
> >> dprintk("%s() properties.props = %p\n", __func__, tvps->props);
> >> ...
> >> if (copy_from_user(tvp, tvps->props, tvps->num *
> >> sizeof(struct dtv_property)))
> >> ----
> >>
> >> Regards,
> >> Markus
> >
> > Seems to be a big issue.
> >
> > Why you ever want to write to a get property?
> >
>
> to read out the API version for example.
> tvps->num is also used in order to check the boundaries of the property array.
>
> Markus
Their are no writes allowed to manipulate get properties.
Cheers,
Hermann
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
