On Tue, Sep 1, 2020 at 5:58 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> On 7/30/20 4:31 PM, Divya Bharathi wrote:
...
> > +bool get_pending_changes(void)
> > +{
> > + struct wmi_interface_priv *priv;
> > +
> > + priv = get_first_interface_priv();
> > + if (priv)
> > + return priv->pending_changes;
> > + return 0;
0 is not boolean.
> > +}
...
> > +int set_attribute(const char *a_name, const char *a_value)
> > +{
> > + int ret = -1;
> > + int i;
> > + u8 *name_len, *value_len;
> > + char *current_password, *attribute_name, *attribute_value;
> > + size_t security_area_size;
> > + size_t string_area_size;
> > + size_t buffer_size;
> > + struct wmi_interface_priv *priv;
> > + char *buffer;
Consider to use reversed xmas tree order. And what -1 means?
> > + /* look up if user set a password for the requests */
> > + current_password = get_current_password("Admin");
> > + if (!current_password)
> > + return -ENODEV;
>
> Can we instead of passing "Admin" and "System" to this function
> just have 2 separate get_current_admin_password and get_current_system_password
> helpers and then drop the error handling ?
>
> > +
> > + /* password is set */
> > + if (strlen(current_password) > 0)
> > + security_area_size = (sizeof(u32) * 2) + strlen(current_password) +
> > + strlen(current_password) % 2;
> > + /* password not set */
> > + else
> > + security_area_size = sizeof(u32) * 2;
>
> Since you are using more then 1 line here please use {} around the state-ments,
> also please put the /* password not set */ after the else:
>
> ...
> } else { /* password not set */
> ...
>
> > + string_area_size = (strlen(a_name) + strlen(a_value))*2;
> > + buffer_size = security_area_size + string_area_size + sizeof(u16) * 2;
> > +
> > + buffer = kzalloc(buffer_size, GFP_KERNEL);
Actually above looks like home grown kasprintf() implementation.
> > + if (!buffer)
> > + return -ENOMEM;
> > +
> > + /* build security area */
> > + if (strlen(current_password) > 0)
> > + populate_security_buffer(buffer, current_password);
> > + name_len = buffer + security_area_size;
> > + attribute_name = name_len + sizeof(u16);
> > + value_len = attribute_name + strlen(a_name)*2;
> > + attribute_value = value_len + sizeof(u16);
> > +
> > + /* turn into UTF16 strings, no NULL terminator */
> > + *name_len = strlen(a_name)*2;
> > + *value_len = strlen(a_value)*2;
> > + for (i = 0; i < strlen(a_name); i++)
> > + attribute_name[i*2] = a_name[i];
> > + for (i = 0; i < strlen(a_value); i++)
> > + attribute_value[i*2] = a_value[i];
>
> This assumes the incoming string is ASCII only and won't
> work when the incoming string is UTF-8. It is probably
> better to use the utf8s_to_utf16s() helper from the nls
> code, this will mean adding a dependency on CONFIG_NLS
> which typically is used for filesystem code, but I think
> that that will be fine.
+1. Also my thought.
> > + mutex_lock(&call_mutex);
> > + priv = get_first_interface_priv();
> > + if (!priv) {
> > + ret = -ENODEV;
> > + pr_err(DRIVER_NAME ": no WMI backend bound");
If you wish, define pr_fmt() rather than putting this DRIVER_NAME to
each of the pr_*() call.
> > + goto out_set_attribute;
> > + }
> > +
> > + ret = call_biosattributes_interface(priv->wdev, buffer, buffer_size,
> > + SETATTRIBUTE_METHOD_ID);
> > + if (ret == -EOPNOTSUPP)
> > + dev_err(&priv->wdev->dev, "admin password must be configured");
> > + else if (ret == -EACCES)
> > + dev_err(&priv->wdev->dev, "invalid password");
> > +
> > + priv->pending_changes = 1;
> > +out_set_attribute:
> > + kfree(buffer);
> > + mutex_unlock(&call_mutex);
> > +
> > + return ret;
> > +}
Above comments, as a rule of thumb, should be considered against
entire code (where appropriate and applicable).
--
With Best Regards,
Andy Shevchenko
