staging: ion: Store a copy of the client name on client creation

Currently, we copy the pointer passed in to ion_client_create without
making a copy of the string itself. This approach is problematic since
it relies on the client keeping the name string in working order.

Cc: Colin Cross <ccross@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
[jstultz: Minor commit subject tweaks]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ion/ion.c

@@ -735,19 +735,18 @@ struct ion_client *ion_client_create(struct ion_device *dev,
 	task_unlock(current->group_leader);
 
 	client = kzalloc(sizeof(struct ion_client), GFP_KERNEL);
-	if (!client) {
-		if (task)
-			put_task_struct(current->group_leader);
-		return ERR_PTR(-ENOMEM);
-	}
+	if (!client)
+		goto err_put_task_struct;
 
 	client->dev = dev;
 	client->handles = RB_ROOT;
 	idr_init(&client->idr);
 	mutex_init(&client->lock);
-	client->name = name;
 	client->task = task;
 	client->pid = pid;
+	client->name = kstrdup(name, GFP_KERNEL);
+	if (!client->name)
+		goto err_free_client;
 
 	down_write(&dev->lock);
 	p = &dev->clients.rb_node;
@@ -776,6 +775,13 @@ struct ion_client *ion_client_create(struct ion_device *dev,
 	up_write(&dev->lock);
 
 	return client;
+
+err_free_client:
+	kfree(client);
+err_put_task_struct:
+	if (task)
+		put_task_struct(current->group_leader);
+	return ERR_PTR(-ENOMEM);
 }
 EXPORT_SYMBOL(ion_client_create);
 
@@ -800,6 +806,7 @@ void ion_client_destroy(struct ion_client *client)
 	debugfs_remove_recursive(client->debug_root);
 	up_write(&dev->lock);
 
+	kfree(client->name);
 	kfree(client);
 }
 EXPORT_SYMBOL(ion_client_destroy);