--- zzzz-none-000/linux-3.10.107/samples/kobject/kobject-example.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/samples/kobject/kobject-example.c	2021-02-04 17:41:59.000000000 +0000
@@ -36,12 +36,18 @@
 static ssize_t foo_store(struct kobject *kobj, struct kobj_attribute *attr,
 			 const char *buf, size_t count)
 {
-	sscanf(buf, "%du", &foo);
+	int ret;
+
+	ret = kstrtoint(buf, 10, &foo);
+	if (ret < 0)
+		return ret;
+
 	return count;
 }
 
+/* Sysfs attributes cannot be world-writable. */
 static struct kobj_attribute foo_attribute =
-	__ATTR(foo, 0666, foo_show, foo_store);
+	__ATTR(foo, 0664, foo_show, foo_store);
 
 /*
  * More complex function where we determine which variable is being accessed by
@@ -62,9 +68,12 @@
 static ssize_t b_store(struct kobject *kobj, struct kobj_attribute *attr,
 		       const char *buf, size_t count)
 {
-	int var;
+	int var, ret;
+
+	ret = kstrtoint(buf, 10, &var);
+	if (ret < 0)
+		return ret;
 
-	sscanf(buf, "%du", &var);
 	if (strcmp(attr->attr.name, "baz") == 0)
 		baz = var;
 	else
@@ -73,9 +82,9 @@
 }
 
 static struct kobj_attribute baz_attribute =
-	__ATTR(baz, 0666, b_show, b_store);
+	__ATTR(baz, 0664, b_show, b_store);
 static struct kobj_attribute bar_attribute =
-	__ATTR(bar, 0666, b_show, b_store);
+	__ATTR(bar, 0664, b_show, b_store);
 
 
 /*
@@ -133,5 +142,5 @@
 
 module_init(example_init);
 module_exit(example_exit);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Greg Kroah-Hartman <greg@kroah.com>");