Re: [alsa-devel] [RFC PATCH 06/40] soundwire: intel: prevent possible dereference in hw_params

From: Vinod Koul
Date: Fri Aug 02 2019 - 13:38:47 EST


On 02-08-19, 11:52, Pierre-Louis Bossart wrote:
>
>
> On 8/2/19 10:57 AM, Vinod Koul wrote:
> > On 02-08-19, 10:16, Pierre-Louis Bossart wrote:
> > >
> > >
> > > On 8/2/19 6:55 AM, Vinod Koul wrote:
> > > > On 25-07-19, 18:39, Pierre-Louis Bossart wrote:
> > > > > This should not happen in production systems but we should test for
> > > > > all callback arguments before invoking the config_stream callback.
> > > >
> > > > so you are saying callback arg is mandatory, if so please document that
> > > > assumption
> > >
> > > no, what this says is that if a config_stream is provided then it needs to
> > > have a valid argument.
> >
> > well typically args are not mandatory..
> >
> > > I am not sure what you mean by "document that assumption", comment in the
> > > code (where?) or SoundWire documentation?
> >
> > The callback documentation which in this is in include/linux/soundwire/sdw_intel.h
> >
>
> /**
> * struct sdw_intel_ops: Intel audio driver callback ops
> *
> * @config_stream: configure the stream with the hw_params
> */
> struct sdw_intel_ops {
> int (*config_stream)(void *arg, void *substream,
> void *dai, void *hw_params, int stream_num);
> };
>
> all parameters are mandatory really, not sure what you are trying to get at.

It would be good to make a note that argument is mandatory!

Thanks
--
~Vinod