[PATCH] driver: make dev_set_name(, NULL) work

[Yinghai Lu <yinghai@kernel.org>]

while looking dev_set_name() calling, there is one
	dev_set_name(&dev->dev, NULL)
to used to try to free the device name, before kfree that device.

need to move the check for device_add in
| commit 8a577ffc75d9194fe8cdb7479236f2081c26ca1f
| Author: Kay Sievers <kay.sievers@vrfy.org>
| Date:   Sat Apr 18 15:05:45 2009 -0700
|
|    driver: dont update dev_name via device_add path
from kobject_set_name_vargs to kobject_add_vargs instead.

in kobject_set_name_vargs will check if fmt is NULL.

actually we need to use dev_set_name(,NULL) later on failing path
and release to prevent leaking

[ Impact: make dev_set_name(, NULL) could kfree old name ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 lib/kobject.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Index: linux-2.6/lib/kobject.c
===================================================================
--- linux-2.6.orig/lib/kobject.c
+++ linux-2.6/lib/kobject.c
@@ -218,8 +218,8 @@ int kobject_set_name_vargs(struct kobjec
 	const char *old_name = kobj->name;
 	char *s;
 
-	if (kobj->name && !fmt)
-		return 0;
+	if (!fmt)
+		goto out;
 
 	kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
 	if (!kobj->name)
@@ -229,6 +229,7 @@ int kobject_set_name_vargs(struct kobjec
 	while ((s = strchr(kobj->name, '/')))
 		s[0] = '!';
 
+out:
 	kfree(old_name);
 	return 0;
 }
@@ -301,11 +302,16 @@ static int kobject_add_varg(struct kobje
 {
 	int retval;
 
+	if (kobj->name && !fmt)
+		goto add_with_name;
+
 	retval = kobject_set_name_vargs(kobj, fmt, vargs);
 	if (retval) {
 		printk(KERN_ERR "kobject: can not set name properly!\n");
 		return retval;
 	}
+
+add_with_name:
 	kobj->parent = parent;
 	return kobject_add_internal(kobj);
 }