Re: [PATCH] greybus: audio: bound the topology section sizes against the fetched size

[Dan Carpenter <error27@gmail.com>]

On Tue, Jun 16, 2026 at 12:01:30PM +0530, Greg Kroah-Hartman wrote:
> On Tue, Jun 16, 2026 at 01:06:12AM -0500, Bryam Vargas via B4 Relay wrote:
> > ---
> >  drivers/staging/greybus/audio_gb.c | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> > 
> > diff --git a/drivers/staging/greybus/audio_gb.c b/drivers/staging/greybus/audio_gb.c
> > index 9d8994fdb41a..144591f1a512 100644
> > --- a/drivers/staging/greybus/audio_gb.c
> > +++ b/drivers/staging/greybus/audio_gb.c
> > @@ -37,6 +37,19 @@ int gb_audio_gb_get_topology(struct gb_connection *connection,
> >  		return ret;
> >  	}
> >  
> > +	/*
> > +	 * The size_* fields are supplied by the module and are used by
> > +	 * gbaudio_tplg_parse_data() to compute offsets into the blob; make
> > +	 * sure the sections fit within the fetched topology, so walking it
> > +	 * cannot read out of bounds.
> > +	 */
> > +	if ((u64)le32_to_cpu(topo->size_dais) + le32_to_cpu(topo->size_controls) +
> > +	    le32_to_cpu(topo->size_widgets) + le32_to_cpu(topo->size_routes) >
> > +	    size - sizeof(*topo)) {
> 
> Are you sure these checks will not overflow?


Yep.  The cast to u64 ensures that.

regards,
dan carpenter