[PATCH] block/rnbd: Constify struct kobj_type

From: Christophe JAILLET
Date: Mon Jul 08 2024 - 14:46:39 EST


'struct kobj_type' is not modified in this driver. It is only used with
kobject_init_and_add() which takes a "const struct kobj_type *" parameter.

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

On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
4082 792 8 4882 1312 drivers/block/rnbd/rnbd-srv-sysfs.o

After:
=====
text data bss dec hex filename
4210 672 8 4890 131a drivers/block/rnbd/rnbd-srv-sysfs.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Compile tested-only
---
drivers/block/rnbd/rnbd-clt-sysfs.c | 2 +-
drivers/block/rnbd/rnbd-srv-sysfs.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 39887556cf95..6ea7c12e3a87 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -475,7 +475,7 @@ void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev)
}
}

-static struct kobj_type rnbd_dev_ktype = {
+static const struct kobj_type rnbd_dev_ktype = {
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = rnbd_dev_groups,
};
diff --git a/drivers/block/rnbd/rnbd-srv-sysfs.c b/drivers/block/rnbd/rnbd-srv-sysfs.c
index cba6ba43c2c2..64780094442c 100644
--- a/drivers/block/rnbd/rnbd-srv-sysfs.c
+++ b/drivers/block/rnbd/rnbd-srv-sysfs.c
@@ -33,7 +33,7 @@ static void rnbd_srv_dev_release(struct kobject *kobj)
kfree(dev);
}

-static struct kobj_type dev_ktype = {
+static const struct kobj_type dev_ktype = {
.sysfs_ops = &kobj_sysfs_ops,
.release = rnbd_srv_dev_release
};
@@ -184,7 +184,7 @@ static void rnbd_srv_sess_dev_release(struct kobject *kobj)
rnbd_destroy_sess_dev(sess_dev, sess_dev->keep_id);
}

-static struct kobj_type rnbd_srv_sess_dev_ktype = {
+static const struct kobj_type rnbd_srv_sess_dev_ktype = {
.sysfs_ops = &kobj_sysfs_ops,
.release = rnbd_srv_sess_dev_release,
};
--
2.45.2