2024-06-14 21:07:06

by Christophe JAILLET

[permalink] [raw]
Subject: [PATCH] ocfs2: Constify struct ocfs2_stack_operations

"struct ocfs2_stack_operations" are not modified in this driver.

Constifying this structure moves some data to a read-only section, so
increase overall security.

In order to do it, "struct ocfs2_stack_plugin" also needs to be adjusted to
this new const qualifier.

On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
6241 644 0 6885 1ae5 fs/ocfs2/stack_o2cb.o

After:
=====
text data bss dec hex filename
6337 548 0 6885 1ae5 fs/ocfs2/stack_o2cb.o

Signed-off-by: Christophe JAILLET <[email protected]>
---
fs/ocfs2/stack_o2cb.c | 2 +-
fs/ocfs2/stack_user.c | 2 +-
fs/ocfs2/stackglue.h | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/ocfs2/stack_o2cb.c b/fs/ocfs2/stack_o2cb.c
index c973c03f6fd8..10157d9d7a9c 100644
--- a/fs/ocfs2/stack_o2cb.c
+++ b/fs/ocfs2/stack_o2cb.c
@@ -404,7 +404,7 @@ static int o2cb_cluster_this_node(struct ocfs2_cluster_connection *conn,
return 0;
}

-static struct ocfs2_stack_operations o2cb_stack_ops = {
+static const struct ocfs2_stack_operations o2cb_stack_ops = {
.connect = o2cb_cluster_connect,
.disconnect = o2cb_cluster_disconnect,
.this_node = o2cb_cluster_this_node,
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index c11406cd87a8..77edcd70f72c 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -1065,7 +1065,7 @@ static int user_cluster_this_node(struct ocfs2_cluster_connection *conn,
return 0;
}

-static struct ocfs2_stack_operations ocfs2_user_plugin_ops = {
+static const struct ocfs2_stack_operations ocfs2_user_plugin_ops = {
.connect = user_cluster_connect,
.disconnect = user_cluster_disconnect,
.this_node = user_cluster_this_node,
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index 3636847fae19..02ab072c528a 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -223,7 +223,7 @@ struct ocfs2_stack_operations {
*/
struct ocfs2_stack_plugin {
char *sp_name;
- struct ocfs2_stack_operations *sp_ops;
+ const struct ocfs2_stack_operations *sp_ops;
struct module *sp_owner;

/* These are managed by the stackglue code. */
--
2.45.2