diff --git a/include/net/sock.h b/include/net/sock.h
index da0534d..43bd515 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -52,6 +52,7 @@
 #include <linux/mm.h>
 #include <linux/security.h>
 #include <linux/slab.h>
+#include <linux/uaccess.h>
 
 #include <linux/filter.h>
 #include <linux/rculist_nulls.h>
@@ -1389,6 +1390,58 @@
 	sk->sk_route_caps &= ~flags;
 }
 
+static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
+					   char __user *from, char *to,
+					   int copy)
+{
+	if (skb->ip_summed == CHECKSUM_NONE) {
+		int err = 0;
+		__wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
+		if (err)
+			return err;
+		skb->csum = csum_block_add(skb->csum, csum, skb->len);
+	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
+		if (!access_ok(VERIFY_READ, from, copy) ||
+		    __copy_from_user_nocache(to, from, copy))
+			return -EFAULT;
+	} else if (copy_from_user(to, from, copy))
+		return -EFAULT;
+
+	return 0;
+}
+
+static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
+				       char __user *from, int copy)
+{
+	int err;
+
+	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), copy);
+	if (err)
+		__skb_trim(skb, skb->len);
+
+	return err;
+}
+
+static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
+					   struct sk_buff *skb,
+					   struct page *page,
+					   int off, int copy)
+{
+	int err;
+
+	err = skb_do_copy_data_nocache(sk, skb, from,
+				       page_address(page) + off, copy);
+	if (err)
+		return err;
+
+	skb->len	     += copy;
+	skb->data_len	     += copy;
+	skb->truesize	     += copy;
+	sk->sk_wmem_queued   += copy;
+	sk_mem_charge(sk, copy);
+	return 0;
+}
+
 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
 				   struct sk_buff *skb, struct page *page,
 				   int off, int copy)