+#ifdef CONFIG_PPP_FILTER
+static int get_filter(void __user *arg, struct sock_filter **p)
+{
+ struct sock_fprog uprog;
+ struct sock_filter *code = NULL;
+ int len, err;
+
+ if (copy_from_user(&uprog, arg, sizeof(uprog)))
+ return -EFAULT;
+
+ if (uprog.len > BPF_MAXINSNS)
+ return -EINVAL;
+
+ if (!uprog.len) {
+ *p = NULL;
+ return 0;
+ }
+
+ len = uprog.len * sizeof(struct sock_filter);
+ code = kmalloc(len, GFP_KERNEL);
+ if (code == NULL)
+ return -ENOMEM;
+
+ if (copy_from_user(code, uprog.filter, len)) {
+ kfree(code);
+ return -EFAULT;
+ }
+
+ err = sk_chk_filter(code, uprog.len);
+ if (err) {
+ kfree(code);
+ return err;
+ }
+
+ *p = code;
+ return uprog.len;
+}
+#endif /* CONFIG_PPP_FILTER */
+