usb: typec: Copy everything from struct typec_capability during registration

Copying everything from struct typec_capability to struct
typec_port during port registration. This will make sure
that under no circumstances the driver can change the values
in the struct typec_capability that the port uses.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191104142435.29960-2-heikki.krogerus@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/class.c

@@ -52,6 +52,7 @@ struct typec_port {
 	struct typec_switch		*sw;
 	struct typec_mux		*mux;
 
+	const struct typec_capability	*orig_cap; /* to be removed */
 	const struct typec_capability	*cap;
 };
 
@@ -968,7 +969,7 @@ preferred_role_store(struct device *dev, struct device_attribute *attr,
 			return -EINVAL;
 	}
 
-	ret = port->cap->try_role(port->cap, role);
+	ret = port->cap->try_role(port->orig_cap, role);
 	if (ret)
 		return ret;
 
@@ -1014,7 +1015,7 @@ static ssize_t data_role_store(struct device *dev,
 		goto unlock_and_ret;
 	}
 
-	ret = port->cap->dr_set(port->cap, ret);
+	ret = port->cap->dr_set(port->orig_cap, ret);
 	if (ret)
 		goto unlock_and_ret;
 
@@ -1071,7 +1072,7 @@ static ssize_t power_role_store(struct device *dev,
 		goto unlock_and_ret;
 	}
 
-	ret = port->cap->pr_set(port->cap, ret);
+	ret = port->cap->pr_set(port->orig_cap, ret);
 	if (ret)
 		goto unlock_and_ret;
 
@@ -1119,7 +1120,7 @@ port_type_store(struct device *dev, struct device_attribute *attr,
 		goto unlock_and_ret;
 	}
 
-	ret = port->cap->port_type_set(port->cap, type);
+	ret = port->cap->port_type_set(port->orig_cap, type);
 	if (ret)
 		goto unlock_and_ret;
 
@@ -1184,7 +1185,7 @@ static ssize_t vconn_source_store(struct device *dev,
 	if (ret)
 		return ret;
 
-	ret = port->cap->vconn_set(port->cap, (enum typec_role)source);
+	ret = port->cap->vconn_set(port->orig_cap, (enum typec_role)source);
 	if (ret)
 		return ret;
 
@@ -1278,6 +1279,7 @@ static void typec_release(struct device *dev)
 	ida_destroy(&port->mode_ids);
 	typec_switch_put(port->sw);
 	typec_mux_put(port->mux);
+	kfree(port->cap);
 	kfree(port);
 }
 
@@ -1579,7 +1581,7 @@ struct typec_port *typec_register_port(struct device *parent,
 	mutex_init(&port->port_type_lock);
 
 	port->id = id;
-	port->cap = cap;
+	port->orig_cap = cap;
 	port->port_type = cap->type;
 	port->prefer_role = cap->prefer_role;
 
@@ -1590,6 +1592,12 @@ struct typec_port *typec_register_port(struct device *parent,
 	port->dev.type = &typec_port_dev_type;
 	dev_set_name(&port->dev, "port%d", id);
 
+	port->cap = kmemdup(cap, sizeof(*cap), GFP_KERNEL);
+	if (!port->cap) {
+		put_device(&port->dev);
+		return ERR_PTR(-ENOMEM);
+	}
+
 	port->sw = typec_switch_get(&port->dev);
 	if (IS_ERR(port->sw)) {
 		put_device(&port->dev);