sysfs: Don't leak secdata when a sysfs_dirent is freed.

While refreshing my sysfs patches I noticed a leak in the secdata
implementation.  We don't free the secdata when we free the
sysfs dirent.

This is a bug in 2.6.32-rc5 that we really should close.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

fs/sysfs/dir.c

@@ -21,6 +21,7 @@
 #include <linux/completion.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/security.h>
 #include "sysfs.h"
 
 DEFINE_MUTEX(sysfs_mutex);
@@ -285,6 +286,9 @@ void release_sysfs_dirent(struct sysfs_dirent * sd)
 		sysfs_put(sd->s_symlink.target_sd);
 	if (sysfs_type(sd) & SYSFS_COPY_NAME)
 		kfree(sd->s_name);
+	if (sd->s_iattr && sd->s_iattr->ia_secdata)
+		security_release_secctx(sd->s_iattr->ia_secdata,
+					sd->s_iattr->ia_secdata_len);
 	kfree(sd->s_iattr);
 	sysfs_free_ino(sd->s_ino);
 	kmem_cache_free(sysfs_dir_cachep, sd);