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

sysfs: fix drivers/base so if an attribute doesn't implement
       show or store method read/write will return -EIO
       instead of 0.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 32f3f09..a293a78 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -36,7 +36,7 @@
 {
 	struct device_attribute * dev_attr = to_dev_attr(attr);
 	struct device * dev = to_dev(kobj);
-	ssize_t ret = 0;
+	ssize_t ret = -EIO;
 
 	if (dev_attr->show)
 		ret = dev_attr->show(dev, buf);
@@ -49,7 +49,7 @@
 {
 	struct device_attribute * dev_attr = to_dev_attr(attr);
 	struct device * dev = to_dev(kobj);
-	ssize_t ret = 0;
+	ssize_t ret = -EIO;
 
 	if (dev_attr->store)
 		ret = dev_attr->store(dev, buf, count);