Re: [PATCH v2 2/8] misc: fastrpc: Fix DSP capabilities request

[Dmitry Baryshkov]

On Tue, May 28, 2024 at 04:59:48PM +0530, Ekansh Gupta wrote:
> Incorrect remote arguments are getting passed when requesting for
> capabilities from DSP. Also there is no requirement to update the
> PD type as it might cause problems for any PD other than user PD.
> In addition to this, the collected capability information is not
> getting copied properly to user. Add changes to address these
> problems and get correct DSP capabilities.

One commit per fix, please.

> 
> Also, DSP capabilities request is sending bad size to utilities skel
> call which is resulting in memory corruption. Pass proper size to
> avoid the corruption.
> 
> Fixes: 6c16fd8bdd40 ("misc: fastrpc: Add support to get DSP capabilities")
> Cc: stable <stable@xxxxxxxxxx>
> Signed-off-by: Ekansh Gupta <quic_ekangupt@xxxxxxxxxxx>
> ---
>  drivers/misc/fastrpc.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> index 4028cb96bcf2..3e1ab58038ed 100644
> --- a/drivers/misc/fastrpc.c
> +++ b/drivers/misc/fastrpc.c
> @@ -1695,14 +1695,14 @@ static int fastrpc_get_info_from_dsp(struct fastrpc_user *fl, uint32_t *dsp_attr
>  
>  	/* Capability filled in userspace */
>  	dsp_attr_buf[0] = 0;
> +	dsp_attr_buf_len -= 1;
>  
>  	args[0].ptr = (u64)(uintptr_t)&dsp_attr_buf_len;
>  	args[0].length = sizeof(dsp_attr_buf_len);
>  	args[0].fd = -1;
>  	args[1].ptr = (u64)(uintptr_t)&dsp_attr_buf[1];
> -	args[1].length = dsp_attr_buf_len;
> +	args[1].length = dsp_attr_buf_len * sizeof(uint32_t);
>  	args[1].fd = -1;
> -	fl->pd = USER_PD;
>  
>  	return fastrpc_internal_invoke(fl, true, FASTRPC_DSP_UTILITIES_HANDLE,
>  				       FASTRPC_SCALARS(0, 1, 1), args);
> @@ -1730,7 +1730,7 @@ static int fastrpc_get_info_from_kernel(struct fastrpc_ioctl_capability *cap,
>  	if (!dsp_attributes)
>  		return -ENOMEM;
>  
> -	err = fastrpc_get_info_from_dsp(fl, dsp_attributes, FASTRPC_MAX_DSP_ATTRIBUTES_LEN);
> +	err = fastrpc_get_info_from_dsp(fl, dsp_attributes, FASTRPC_MAX_DSP_ATTRIBUTES);
>  	if (err == DSP_UNSUPPORTED_API) {
>  		dev_info(&cctx->rpdev->dev,
>  			 "Warning: DSP capabilities not supported on domain: %d\n", domain);
> @@ -1783,7 +1783,7 @@ static int fastrpc_get_dsp_info(struct fastrpc_user *fl, char __user *argp)
>  	if (err)
>  		return err;
>  
> -	if (copy_to_user(argp, &cap.capability, sizeof(cap.capability)))
> +	if (copy_to_user(argp, &cap, sizeof(cap)))
>  		return -EFAULT;
>  
>  	return 0;
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry