Re: [PATCH] ASoC: SOF: ipc4-mtrace: prevent underflow in sof_ipc4_priority_mask_dfs_write()

["Péter Ujfalusi" <peter.ujfalusi@linux.intel.com>]

On 19/01/2023 16:58, Dan Carpenter wrote:
> The "id" comes from the user.  Change the type to unsigned to prevent
> an array underflow.
> 
> Fixes: f4ea22f7aa75 ("ASoC: SOF: ipc4: Add support for mtrace log extraction")
> Signed-off-by: Dan Carpenter <error27@gmail.com>

Acked-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

> ---
>  sound/soc/sof/ipc4-mtrace.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/sound/soc/sof/ipc4-mtrace.c b/sound/soc/sof/ipc4-mtrace.c
> index 70dea8ae706e..0ec6ef681012 100644
> --- a/sound/soc/sof/ipc4-mtrace.c
> +++ b/sound/soc/sof/ipc4-mtrace.c
> @@ -344,9 +344,10 @@ static ssize_t sof_ipc4_priority_mask_dfs_write(struct file *file,
>  						size_t count, loff_t *ppos)
>  {
>  	struct sof_mtrace_priv *priv = file->private_data;
> -	int id, ret;
> +	unsigned int id;
>  	char *buf;
>  	u32 mask;
> +	int ret;
>  
>  	/*
>  	 * To update Nth mask entry, write:
> @@ -357,9 +358,9 @@ static ssize_t sof_ipc4_priority_mask_dfs_write(struct file *file,
>  	if (IS_ERR(buf))
>  		return PTR_ERR(buf);
>  
> -	ret = sscanf(buf, "%d,0x%x", &id, &mask);
> +	ret = sscanf(buf, "%u,0x%x", &id, &mask);
>  	if (ret != 2) {
> -		ret = sscanf(buf, "%d,%x", &id, &mask);
> +		ret = sscanf(buf, "%u,%x", &id, &mask);
>  		if (ret != 2) {
>  			ret = -EINVAL;
>  			goto out;

-- 
Péter