platform/x86: dell: dcdbas: Constify 'struct bin_attribute'

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

While at it switch from the custom DCDBAS_BIN_ATTR_RW() to the identical
BIN_ATTR_RW() macro.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20241202-sysfs-const-bin_attr-pdx86-v1-1-9ab204c2a814@weissschuh.net
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/dell/dcdbas.c b/drivers/platform/x86/dell/dcdbas.c
index 0aeb8149c16bfcb5df3cad77b69d7e5978ce6536..8149be25fa267ca027d809c45fe1c3f47fcfd453 100644 (file)
--- a/drivers/platform/x86/dell/dcdbas.c
+++ b/drivers/platform/x86/dell/dcdbas.c
@@ -163,7 +163,7 @@ static ssize_t smi_data_buf_size_store(struct device *dev,
 }
 
 static ssize_t smi_data_read(struct file *filp, struct kobject *kobj,
-                            struct bin_attribute *bin_attr,
+                            const struct bin_attribute *bin_attr,
                             char *buf, loff_t pos, size_t count)
 {
        ssize_t ret;
@@ -176,7 +176,7 @@ static ssize_t smi_data_read(struct file *filp, struct kobject *kobj,
 }
 
 static ssize_t smi_data_write(struct file *filp, struct kobject *kobj,
-                             struct bin_attribute *bin_attr,
+                             const struct bin_attribute *bin_attr,
                              char *buf, loff_t pos, size_t count)
 {
        ssize_t ret;
@@ -636,9 +636,9 @@ static struct notifier_block dcdbas_reboot_nb = {
        .priority = INT_MIN
 };
 
-static DCDBAS_BIN_ATTR_RW(smi_data);
+static const BIN_ATTR_ADMIN_RW(smi_data, 0);
 
-static struct bin_attribute *dcdbas_bin_attrs[] = {
+static const struct bin_attribute *const dcdbas_bin_attrs[] = {
        &bin_attr_smi_data,
        NULL
 };
@@ -662,7 +662,7 @@ static struct attribute *dcdbas_dev_attrs[] = {
 
 static const struct attribute_group dcdbas_attr_group = {
        .attrs = dcdbas_dev_attrs,
-       .bin_attrs = dcdbas_bin_attrs,
+       .bin_attrs_new = dcdbas_bin_attrs,
 };
 
 static int dcdbas_probe(struct platform_device *dev)

diff --git a/drivers/platform/x86/dell/dcdbas.h b/drivers/platform/x86/dell/dcdbas.h
index 942a23ddded0592d2279da2dfee05113e8f4dbff..a05d7f667586310e379e38601309acdfad25645a 100644 (file)
--- a/drivers/platform/x86/dell/dcdbas.h
+++ b/drivers/platform/x86/dell/dcdbas.h
@@ -56,14 +56,6 @@
 #define DCDBAS_DEV_ATTR_WO(_name) \
        DEVICE_ATTR(_name,0200,NULL,_name##_store);
 
-#define DCDBAS_BIN_ATTR_RW(_name) \
-struct bin_attribute bin_attr_##_name = { \
-       .attr =  { .name = __stringify(_name), \
-                  .mode = 0600 }, \
-       .read =  _name##_read, \
-       .write = _name##_write, \
-}
-
 struct smi_cmd {
        __u32 magic;
        __u32 ebx;