Re: [PATCH 1/2] ASoC: SOF: ipc-msg-injector: Propagate write errors correctly

From: "Péter Ujfalusi" <peter.ujfalusi@linux.intel.com>
To: Dan Carpenter <dan.carpenter@oracle.com>,
	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: alsa-devel@alsa-project.org,
	Kai Vehmanen <kai.vehmanen@linux.intel.com>,
	Bard Liao <yung-chuan.liao@linux.intel.com>,
	Takashi Iwai <tiwai@suse.com>,
	kernel-janitors@vger.kernel.org,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	Ranjani Sridharan <ranjani.sridharan@linux.intel.com>,
	Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>,
	Rander Wang <rander.wang@intel.com>,
	Daniel Baluta <daniel.baluta@nxp.com>,
	sound-open-firmware@alsa-project.org
Subject: Re: [PATCH 1/2] ASoC: SOF: ipc-msg-injector: Propagate write errors correctly
Date: Fri, 3 Jun 2022 12:48:13 +0300	[thread overview]
Message-ID: <c756fc79-281e-9c41-6070-c79ca6eb7c32@linux.intel.com> (raw)
In-Reply-To: <Yph+Cd+JrfOH0i7z@kili>

On 02/06/2022 12:08, Dan Carpenter wrote:
> This code is supposed to propagate errors from simple_write_to_buffer()
> or return -EFAULT if "size != count".  However "size" needs to be signed
> for the code to work correctly and the case where "size == 0" is not
> handled correctly.

Thanks Dan!

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

> Fixes: 066c67624d8c ("ASoC: SOF: ipc-msg-injector: Add support for IPC4 messages")
> Fixes: 2f0b1b013bbc ("ASoC: SOF: debug: Add support for IPC message injection")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
>  sound/soc/sof/sof-client-ipc-msg-injector.c | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/sound/soc/sof/sof-client-ipc-msg-injector.c b/sound/soc/sof/sof-client-ipc-msg-injector.c
> index 03490a4d4ae7..030cb97d7713 100644
> --- a/sound/soc/sof/sof-client-ipc-msg-injector.c
> +++ b/sound/soc/sof/sof-client-ipc-msg-injector.c
> @@ -150,7 +150,7 @@ static ssize_t sof_msg_inject_dfs_write(struct file *file, const char __user *bu
>  {
>  	struct sof_client_dev *cdev = file->private_data;
>  	struct sof_msg_inject_priv *priv = cdev->data;
> -	size_t size;
> +	ssize_t size;
>  	int ret;
>  
>  	if (*ppos)
> @@ -158,8 +158,10 @@ static ssize_t sof_msg_inject_dfs_write(struct file *file, const char __user *bu
>  
>  	size = simple_write_to_buffer(priv->tx_buffer, priv->max_msg_size,
>  				      ppos, buffer, count);
> +	if (size < 0)
> +		return size;
>  	if (size != count)
> -		return size > 0 ? -EFAULT : size;
> +		return -EFAULT;
>  
>  	memset(priv->rx_buffer, 0, priv->max_msg_size);
>  
> @@ -179,7 +181,7 @@ static ssize_t sof_msg_inject_ipc4_dfs_write(struct file *file,
>  	struct sof_client_dev *cdev = file->private_data;
>  	struct sof_msg_inject_priv *priv = cdev->data;
>  	struct sof_ipc4_msg *ipc4_msg = priv->tx_buffer;
> -	size_t size;
> +	ssize_t size;
>  	int ret;
>  
>  	if (*ppos)
> @@ -192,8 +194,10 @@ static ssize_t sof_msg_inject_ipc4_dfs_write(struct file *file,
>  	size = simple_write_to_buffer(&ipc4_msg->header_u64,
>  				      sizeof(ipc4_msg->header_u64),
>  				      ppos, buffer, count);
> +	if (size < 0)
> +		return size;
>  	if (size != sizeof(ipc4_msg->header_u64))
> -		return size > 0 ? -EFAULT : size;
> +		return -EFAULT;
>  
>  	count -= size;
>  	if (!count) {
> @@ -201,8 +205,10 @@ static ssize_t sof_msg_inject_ipc4_dfs_write(struct file *file,
>  		size = simple_write_to_buffer(ipc4_msg->data_ptr,
>  					      priv->max_msg_size, ppos, buffer,
>  					      count);
> +		if (size < 0)
> +			return size;
>  		if (size != count)
> -			return size > 0 ? -EFAULT : size;
> +			return -EFAULT;
>  	}
>  
>  	ipc4_msg->data_size = count;

-- 
Péter