Re: [OOPS][RESEND] 2.6.0-test4-mm4

[Andrew Morton <akpm@osdl.org>]

Andrew Morton <akpm@osdl.org> wrote:
>
> This should fix it up.

oops, that had a use-after-free as well.

I don't really see a sane way of maintaining kobj->k_name going into
t->release(), so the release() implementations will just have to handle a
NULL kobj->k_name.


diff -puN lib/kobject.c~kobject-unlimited-name-lengths-use-after-free-fix lib/kobject.c
--- 25/lib/kobject.c~kobject-unlimited-name-lengths-use-after-free-fix	2003-09-01 22:20:27.000000000 -0700
+++ 25-akpm/lib/kobject.c	2003-09-01 22:36:16.000000000 -0700
@@ -443,15 +443,20 @@ void kobject_cleanup(struct kobject * ko
 {
 	struct kobj_type * t = get_ktype(kobj);
 	struct kset * s = kobj->kset;
+	char *name = NULL;
 
 	pr_debug("kobject %s: cleaning up\n",kobject_name(kobj));
+
+	if (kobj->k_name != kobj->name)
+		name = kobj->k_name;
+	kobj->k_name = NULL;
 	if (t && t->release)
 		t->release(kobj);
 	if (s)
 		kset_put(s);
-	if (kobj->k_name != kobj->name)
-		kfree(kobj->k_name);
-	kobj->k_name = NULL;
+
+	if (name)
+		kfree(name);
 }
 
 /**

_