On Mon, Jun 08, 2026 at 02:29:13PM +0800, Jianping Li wrote:
>
> On 6/8/2026 2:11 PM, Dmitry Baryshkov wrote:
> > On Tue, Jun 02, 2026 at 03:17:48PM +0800, Jianping Li wrote:
> > > Audio PD static process creation assumes that a reserved-memory
> > > region is defined in DT and exposed via cctx->remote_heap.
> > >
> > > If reserved-memory is missing or incomplete, the driver may pass
> > > invalid address/size information to the DSP, leading to undefined
> > > behavior or crashes.
> > >
> > > Add explicit validation for remote_heap presence and size before
> > > sending the memory to DSP, and fail early if the configuration is
> > > invalid.
> > >
> > > Fixes: 0871561055e66 ("misc: fastrpc: Add support for audiopd")
> > > Cc: [email protected]
> > > Signed-off-by: Jianping Li <[email protected]>
> > > ---
> > > drivers/misc/fastrpc.c | 7 +++++++
> > > 1 file changed, 7 insertions(+)
> > >
> > > diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> > > index a8a58f889d07..f46a8f53970d 100644
> > > --- a/drivers/misc/fastrpc.c
> > > +++ b/drivers/misc/fastrpc.c
> > > @@ -1354,6 +1354,13 @@ static int
> > > fastrpc_init_create_static_process(struct fastrpc_user *fl,
> > > } inbuf;
> > > u32 sc;
> > > + if (!fl->cctx->remote_heap ||
> > > + !fl->cctx->remote_heap->dma_addr ||
> > > + !fl->cctx->remote_heap->size) {
> > > + err = -ENOMEM;
> > > + dev_dbg(fl->sctx->dev, "remote heap memory region is not
> > > added\n");
> > > + return err;
> > > + }
> > Won't this check without the next commit break the kernel? I don't see
> > where else the remote heap is being allocated.
>
> Yes, this check depends on remote_heap being populated during rpmsg
> probe from the reserved-memory region, introduced in a subsequent
> patch in this series.
>
> If there is no dependency on the next series, the remote_heap allocation here
> after the if check.
> The logic will be wrong.
So, at least you need to squash those two together.
>
> >
> > > args = kzalloc_objs(*args, FASTRPC_CREATE_STATIC_PROCESS_NARGS);
> > > if (!args)
> > > return -ENOMEM;
> > > --
> > > 2.43.0
> > >
--
With best wishes
Dmitry
