sysctl: An easier to read version of find_subdir

Suggested-by:  Lucian Adrian Grijincu <lucian.grijincu@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 27e265b..ebe8b30 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -833,9 +833,9 @@
 	entry = find_entry(&head, dir, name, namelen);
 	if (!entry)
 		return ERR_PTR(-ENOENT);
-	if (S_ISDIR(entry->mode))
-		return container_of(head, struct ctl_dir, header);
-	return ERR_PTR(-ENOTDIR);
+	if (!S_ISDIR(entry->mode))
+		return ERR_PTR(-ENOTDIR);
+	return container_of(head, struct ctl_dir, header);
 }
 
 static struct ctl_dir *new_dir(struct ctl_table_set *set,