Re: [PATCH v5 3/5] misc: fastrpc: Fail Audio PD init when reserved memory is missing

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

On Fri, May 15, 2026 at 08:42:15PM +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: stable@kernel.org
> Signed-off-by: Jianping Li <jianping.li@oss.qualcomm.com>
> ---
>  drivers/misc/fastrpc.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> index 3c7c3b410d7d..a0337cce77f3 100644
> --- a/drivers/misc/fastrpc.c
> +++ b/drivers/misc/fastrpc.c
> @@ -1363,6 +1363,12 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
>  	args[1].length = inbuf.namelen;
>  	args[1].fd = -1;
>  
> +	if (!fl->cctx->remote_heap ||
> +	    !fl->cctx->remote_heap->dma_addr ||
> +	    !fl->cctx->remote_heap->size) {

I guess that !dma_addr || !size should fail much earlier than here.

> +		err = -ENOMEM;
> +		goto err;
> +	}
>  	pages[0].addr = fl->cctx->remote_heap->dma_addr;
>  	pages[0].size = fl->cctx->remote_heap->size;
>  
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry