[PATCH] platform/x86: dell-smbios-wmi: Unlock on error in dell_smbios_wmi_call()

[PATCH] platform/x86: dell-smbios-wmi: Unlock on error in dell_smbios_wmi_call()

[Dan Carpenter]

We have to unlock before returning if get_first_smbios_priv() fails.

Fixes: 1a258e670434 ("platform/x86: dell-smbios-wmi: Add new WMI dispatcher driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c
index 35c13815b24c..7b0e3ca74ca0 100644
--- a/drivers/platform/x86/dell-smbios-wmi.c
+++ b/drivers/platform/x86/dell-smbios-wmi.c
@@ -91,8 +91,10 @@ int dell_smbios_wmi_call(struct calling_interface_buffer *buffer)
 
 	mutex_lock(&call_mutex);
 	priv = get_first_smbios_priv();
-	if (!priv)
-		return -ENODEV;
+	if (!priv) {
+		ret = -ENODEV;
+		goto unlock;
+	}
 
 	size = sizeof(struct calling_interface_buffer);
 	difference = priv->req_buf_size - sizeof(u64) - size;
@@ -101,6 +103,7 @@ int dell_smbios_wmi_call(struct calling_interface_buffer *buffer)
 	memcpy(&priv->buf->std, buffer, size);
 	ret = run_smbios_call(priv->wdev);
 	memcpy(buffer, &priv->buf->std, size);
+unlock:
 	mutex_unlock(&call_mutex);
 
 	return ret;

RE: [PATCH] platform/x86: dell-smbios-wmi: Unlock on error in dell_smbios_wmi_call()

[Mario.Limonciello]

> -----Original Message-----
> From: Dan Carpenter [mailto:dan.carpenter@oracle.com]
> Sent: Monday, November 13, 2017 4:06 AM
> To: Limonciello, Mario <Mario_Limonciello@Dell.com>
> Cc: Darren Hart <dvhart@infradead.org>; Andy Shevchenko
> <andy@infradead.org>; platform-driver-x86@vger.kernel.org; kernel-
> janitors@vger.kernel.org
> Subject: [PATCH] platform/x86: dell-smbios-wmi: Unlock on error in
> dell_smbios_wmi_call()
> 
> We have to unlock before returning if get_first_smbios_priv() fails.
> 
> Fixes: 1a258e670434 ("platform/x86: dell-smbios-wmi: Add new WMI dispatcher
> driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-
> smbios-wmi.c
> index 35c13815b24c..7b0e3ca74ca0 100644
> --- a/drivers/platform/x86/dell-smbios-wmi.c
> +++ b/drivers/platform/x86/dell-smbios-wmi.c
> @@ -91,8 +91,10 @@ int dell_smbios_wmi_call(struct calling_interface_buffer
> *buffer)
> 
>  	mutex_lock(&call_mutex);
>  	priv = get_first_smbios_priv();
> -	if (!priv)
> -		return -ENODEV;
> +	if (!priv) {
> +		ret = -ENODEV;
> +		goto unlock;
> +	}
> 
>  	size = sizeof(struct calling_interface_buffer);
>  	difference = priv->req_buf_size - sizeof(u64) - size;
> @@ -101,6 +103,7 @@ int dell_smbios_wmi_call(struct calling_interface_buffer
> *buffer)
>  	memcpy(&priv->buf->std, buffer, size);
>  	ret = run_smbios_call(priv->wdev);
>  	memcpy(buffer, &priv->buf->std, size);
> +unlock:
>  	mutex_unlock(&call_mutex);
> 
>  	return ret;

Hi Dan,

Thanks for submitting.  This exact same fix is in the subsystem "testing" branch
but hasn't yet been promoted to -next.

http://git.infradead.org/users/dvhart/linux-platform-drivers-x86.git/commit/307ab2a99d190d3a7949258b8551b66887ce8cf4