From 030c1d2bfcc2187650fb975456ca0b61a5bb77f4 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 8 May 2008 14:41:00 -0700 Subject: kobject: Fix kobject_rename and !CONFIG_SYSFS When looking at kobject_rename I found two bugs with that exist when sysfs support is disabled in the kernel. kobject_rename does not change the name on the kobject when sysfs support is not compiled in. kobject_rename without locking attempts to check the validity of a rename operation, which the kobject layer simply does not have the infrastructure to do. This patch documents the previously unstated requirement of kobject_rename that is the responsibility of the caller to provide mutual exclusion and to be certain that the new_name for the kobject is valid. This patch modifies sysfs_rename_dir in !CONFIG_SYSFS case to call kobject_set_name to actually change the kobject_name. This patch removes the bogus and misleading check in kobject_rename that attempts to see if a rename is valid. The check is bogus because we do not have the proper locking. The check is misleading because it looks like we can and do perform checking at the kobject level that we don't. Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman --- lib/kobject.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) (limited to 'lib') diff --git a/lib/kobject.c b/lib/kobject.c index fbf0ae2..ae6bb90 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -387,6 +387,11 @@ EXPORT_SYMBOL_GPL(kobject_init_and_add); * kobject_rename - change the name of an object * @kobj: object in question. * @new_name: object's new name + * + * It is the responsibility of the caller to provide mutual + * exclusion between two different calls of kobject_rename + * on the same kobject and to ensure that new_name is valid and + * won't conflict with other kobjects. */ int kobject_rename(struct kobject *kobj, const char *new_name) { @@ -401,19 +406,6 @@ int kobject_rename(struct kobject *kobj, const char *new_name) if (!kobj->parent) return -EINVAL; - /* see if this name is already in use */ - if (kobj->kset) { - struct kobject *temp_kobj; - temp_kobj = kset_find_obj(kobj->kset, new_name); - if (temp_kobj) { - printk(KERN_WARNING "kobject '%s' cannot be renamed " - "to '%s' as '%s' is already in existence.\n", - kobject_name(kobj), new_name, new_name); - kobject_put(temp_kobj); - return -EINVAL; - } - } - devpath = kobject_get_path(kobj, GFP_KERNEL); if (!devpath) { error = -ENOMEM; -- cgit v1.1