[PATCH] sysfs: (rest) if show/store is missing return -EIO

sysfs: fix the rest of the kernel so if an attribute doesn't
       implement show or store method read/write will return
       -EIO instead of 0 or -EINVAL or -EPERM.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

7 files changed, 12 insertions, 12 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 119c94093a13..e85885593280 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -65,14 +65,14 @@ static ssize_t acpi_device_attr_show(struct kobject *kobj,
 {
         struct acpi_device *device = to_acpi_device(kobj);
         struct acpi_device_attribute *attribute = to_handle_attr(attr);
-        return attribute->show ? attribute->show(device, buf) : 0;
+        return attribute->show ? attribute->show(device, buf) : -EIO;
 }
 static ssize_t acpi_device_attr_store(struct kobject *kobj,
                 struct attribute *attr, const char *buf, size_t len)
 {
         struct acpi_device *device = to_acpi_device(kobj);
         struct acpi_device_attribute *attribute = to_handle_attr(attr);
-        return attribute->store ? attribute->store(device, buf, len) : len;
+        return attribute->store ? attribute->store(device, buf, len) : -EIO;
 }
 
 static struct sysfs_ops acpi_device_sysfs_ops = {
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 03b5fb2ddcf4..bf62dfe4976a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -521,7 +521,7 @@ static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
         policy = cpufreq_cpu_get(policy->cpu);
         if (!policy)
                 return -EINVAL;
-        ret = fattr->show ? fattr->show(policy,buf) : 0;
+        ret = fattr->show ? fattr->show(policy,buf) : -EIO;
         cpufreq_cpu_put(policy);
         return ret;
 }
@@ -535,7 +535,7 @@ static ssize_t store(struct kobject * kobj, struct attribute * attr,
         policy = cpufreq_cpu_get(policy->cpu);
         if (!policy)
                 return -EINVAL;
-        ret = fattr->store ? fattr->store(policy,buf,count) : 0;
+        ret = fattr->store ? fattr->store(policy,buf,count) : -EIO;
         cpufreq_cpu_put(policy);
         return ret;
 }
diff --git a/drivers/firmware/edd.c b/drivers/firmware/edd.c
index 33b669e6f977..6996476669f1 100644
--- a/drivers/firmware/edd.c
+++ b/drivers/firmware/edd.c
@@ -115,7 +115,7 @@ edd_attr_show(struct kobject * kobj, struct attribute *attr, char *buf)
 {
         struct edd_device *dev = to_edd_device(kobj);
         struct edd_attribute *edd_attr = to_edd_attr(attr);
-        ssize_t ret = 0;
+        ssize_t ret = -EIO;
 
         if (edd_attr->show)
                 ret = edd_attr->show(dev, buf);
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 0287ff65963b..a3451cb94004 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -352,7 +352,7 @@ static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
 {
         struct efivar_entry *var = to_efivar_entry(kobj);
         struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
-        ssize_t ret = 0;
+        ssize_t ret = -EIO;
 
         if (!capable(CAP_SYS_ADMIN))
                 return -EACCES;
@@ -368,7 +368,7 @@ static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
 {
         struct efivar_entry *var = to_efivar_entry(kobj);
         struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
-        ssize_t ret = 0;
+        ssize_t ret = -EIO;
 
         if (!capable(CAP_SYS_ADMIN))
                 return -EACCES;
diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c
index 5febd6d8b885..90d51b179abe 100644
--- a/drivers/infiniband/core/sysfs.c
+++ b/drivers/infiniband/core/sysfs.c
@@ -71,7 +71,7 @@ static ssize_t port_attr_show(struct kobject *kobj,
         struct ib_port *p = container_of(kobj, struct ib_port, kobj);
 
         if (!port_attr->show)
-                return 0;
+                return -EIO;
 
         return port_attr->show(p, port_attr, buf);
 }
diff --git a/kernel/params.c b/kernel/params.c
index 5513844bec13..d586c35ef8fc 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -629,7 +629,7 @@ static ssize_t module_attr_show(struct kobject *kobj,
         mk = to_module_kobject(kobj);
 
         if (!attribute->show)
-                return -EPERM;
+                return -EIO;
 
         if (!try_module_get(mk->mod))
                 return -ENODEV;
@@ -653,7 +653,7 @@ static ssize_t module_attr_store(struct kobject *kobj,
         mk = to_module_kobject(kobj);
 
         if (!attribute->store)
-                return -EPERM;
+                return -EIO;
 
         if (!try_module_get(mk->mod))
                 return -ENODEV;
diff --git a/security/seclvl.c b/security/seclvl.c
index 8a0ab0d7949e..c8e87b22c9bd 100644
--- a/security/seclvl.c
+++ b/security/seclvl.c
@@ -155,7 +155,7 @@ seclvl_attr_store(struct kobject *kobj,
         struct seclvl_obj *obj = container_of(kobj, struct seclvl_obj, kobj);
         struct seclvl_attribute *attribute =
             container_of(attr, struct seclvl_attribute, attr);
-        return (attribute->store ? attribute->store(obj, buf, len) : 0);
+        return attribute->store ? attribute->store(obj, buf, len) : -EIO;
 }
 
 static ssize_t
@@ -164,7 +164,7 @@ seclvl_attr_show(struct kobject *kobj, struct attribute *attr, char *buf)
         struct seclvl_obj *obj = container_of(kobj, struct seclvl_obj, kobj);
         struct seclvl_attribute *attribute =
             container_of(attr, struct seclvl_attribute, attr);
-        return (attribute->show ? attribute->show(obj, buf) : 0);
+        return attribute->show ? attribute->show(obj, buf) : -EIO;
 }
 
 /**