i2c: virtio: Constify struct i2c_algorithm and struct virtio_device_id
authorChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Sun, 8 Sep 2024 06:52:07 +0000 (08:52 +0200)
committerAndi Shyti <andi.shyti@kernel.org>
Mon, 9 Sep 2024 22:36:50 +0000 (00:36 +0200)
'struct i2c_algorithm' and 'struct virtio_device_id' are not modified in
this driver.

Constifying this structure moves some data to a read-only section, so
increase overall security, especially when the structure holds some
function pointers, which is the case for struct i2c_algorithm.

On a x86_64, with allmodconfig:
Before:
======
   text    data     bss     dec     hex filename
   6663     568      16    7247    1c4f drivers/i2c/busses/i2c-virtio.o

After:
=====
   text    data     bss     dec     hex filename
   6735     472      16    7223    1c37 drivers/i2c/busses/i2c-virtio.o

--
Compile tested only

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
drivers/i2c/busses/i2c-virtio.c

index 52ba1e0845ca78480592b58b1d8ab2744ee9a9ab..2a351f961b89932f770db00d22fc78ee35c2f655 100644 (file)
@@ -182,7 +182,7 @@ static u32 virtio_i2c_func(struct i2c_adapter *adap)
        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 }
 
-static struct i2c_algorithm virtio_algorithm = {
+static const struct i2c_algorithm virtio_algorithm = {
        .xfer = virtio_i2c_xfer,
        .functionality = virtio_i2c_func,
 };
@@ -237,7 +237,7 @@ static void virtio_i2c_remove(struct virtio_device *vdev)
        virtio_i2c_del_vqs(vdev);
 }
 
-static struct virtio_device_id id_table[] = {
+static const struct virtio_device_id id_table[] = {
        { VIRTIO_ID_I2C_ADAPTER, VIRTIO_DEV_ANY_ID },
        {}
 };