driver core: check start node in klist_iter_init_node

klist_iter_init_node() takes a node as a start argument.
However, this node might not be valid anymore.
This patch updates the klist_iter_init_node() and
dependent functions to return an error if so.
All calling functions have been audited to check
for a return code here.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Greg Kroah-Hartmann <gregkh@linuxfoundation.org>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Stable Kernel <stable@kernel.org>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 6 insertions, 6 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 5ad17cccdd71..50429b911b21 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -128,7 +128,7 @@ struct subsys_dev_iter {
         struct klist_iter               ki;
         const struct device_type        *type;
 };
-void subsys_dev_iter_init(struct subsys_dev_iter *iter,
+int subsys_dev_iter_init(struct subsys_dev_iter *iter,
                          struct bus_type *subsys,
                          struct device *start,
                          const struct device_type *type);
@@ -380,10 +380,10 @@ int class_compat_create_link(struct class_compat *cls, struct device *dev,
 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
                               struct device *device_link);
 
-extern void class_dev_iter_init(struct class_dev_iter *iter,
-                                struct class *class,
-                                struct device *start,
-                                const struct device_type *type);
+extern int class_dev_iter_init(struct class_dev_iter *iter,
+                               struct class *class,
+                               struct device *start,
+                               const struct device_type *type);
 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
 extern void class_dev_iter_exit(struct class_dev_iter *iter);
 
diff --git a/include/linux/klist.h b/include/linux/klist.h
index a370ce57cf1d..9f633230f189 100644
--- a/include/linux/klist.h
+++ b/include/linux/klist.h
@@ -60,7 +60,7 @@ struct klist_iter {
 
 
 extern void klist_iter_init(struct klist *k, struct klist_iter *i);
-extern void klist_iter_init_node(struct klist *k, struct klist_iter *i,
+extern int klist_iter_init_node(struct klist *k, struct klist_iter *i,
                                  struct klist_node *n);
 extern void klist_iter_exit(struct klist_iter *i);
 extern struct klist_node *klist_next(struct klist_iter *i);