usb: gadget: configfs: Constify struct config_item_type

Commit Message

Christophe JAILLET Aug. 10, 2024, 9:05 p.m. UTC

'struct config_item_type' is not modified in this file.

Apparently, these structures are only used with
config_group_init_type_name() which takes a const struct config_item_type*
as a 3rd argument.

Constifying this structure moves some data to a read-only section, so
increase overall security, especially when the structure holds some
function pointers.

On a x86_64, with allmodconfig:
Before:
======
   text	   data	    bss	    dec	    hex	filename
  40834	   5112	     64	  46010	   b3ba	drivers/usb/gadget/configfs.o

After:
=====
   text	   data	    bss	    dec	    hex	filename
  41218	   4728	     64	  46010	   b3ba	drivers/usb/gadget/configfs.o

Signed-off-by: Christophe JAILLET <[e-mail]>
---
Compile tested-only.
---
 drivers/usb/gadget/configfs.c       | 8 ++++----
 include/linux/usb/gadget_configfs.h | 4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

Patch

diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index e0bf2b2bfc01..5cba3e8d626c 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -902,7 +902,7 @@  static struct configfs_group_operations gadget_language_langid_group_ops = {
 	.drop_item		= gadget_language_string_drop,
 };
 
-static struct config_item_type gadget_language_type = {
+static const struct config_item_type gadget_language_type = {
 	.ct_item_ops	= &gadget_language_langid_item_ops,
 	.ct_group_ops	= &gadget_language_langid_group_ops,
 	.ct_attrs	= gadget_language_langid_attrs,
@@ -961,7 +961,7 @@  static struct configfs_group_operations gadget_language_group_ops = {
 	.drop_item      = &gadget_language_drop,
 };
 
-static struct config_item_type gadget_language_strings_type = {
+static const struct config_item_type gadget_language_strings_type = {
 	.ct_group_ops   = &gadget_language_group_ops,
 	.ct_owner       = THIS_MODULE,
 };
@@ -1106,7 +1106,7 @@  static struct configfs_attribute *webusb_attrs[] = {
 	NULL,
 };
 
-static struct config_item_type webusb_type = {
+static const struct config_item_type webusb_type = {
 	.ct_attrs	= webusb_attrs,
 	.ct_owner	= THIS_MODULE,
 };
@@ -1263,7 +1263,7 @@  static struct configfs_item_operations os_desc_ops = {
 	.drop_link		= os_desc_unlink,
 };
 
-static struct config_item_type os_desc_type = {
+static const struct config_item_type os_desc_type = {
 	.ct_item_ops	= &os_desc_ops,
 	.ct_attrs	= os_desc_attrs,
 	.ct_owner	= THIS_MODULE,
diff --git a/include/linux/usb/gadget_configfs.h b/include/linux/usb/gadget_configfs.h
index 6a552dd4dec9..6b5d6838f865 100644
--- a/include/linux/usb/gadget_configfs.h
+++ b/include/linux/usb/gadget_configfs.h
@@ -34,7 +34,7 @@  static struct configfs_item_operations struct_in##_langid_item_ops = {	\
 	.release                = struct_in##_attr_release,		\
 };									\
 									\
-static struct config_item_type struct_in##_langid_type = {		\
+static const struct config_item_type struct_in##_langid_type = {	\
 	.ct_item_ops	= &struct_in##_langid_item_ops,			\
 	.ct_attrs	= struct_in##_langid_attrs,			\
 	.ct_owner	= THIS_MODULE,					\
@@ -91,7 +91,7 @@  static struct configfs_group_operations struct_in##_strings_ops = {	\
 	.drop_item      = &struct_in##_strings_drop,			\
 };									\
 									\
-static struct config_item_type struct_in##_strings_type = {		\
+static const struct config_item_type struct_in##_strings_type = {	\
 	.ct_group_ops   = &struct_in##_strings_ops,			\
 	.ct_owner       = THIS_MODULE,					\
 }