diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 228bf0c5ff195daed1e24bf5128c68d7e6110a04..ea92f23ffaf120d781fee977c20072398e796d36 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4535,26 +4535,13 @@ tcp_collapse(struct sock *sk, struct sk_buff_head *list,
 		return;
 
 	while (before(start, end)) {
+		int copy = min_t(int, SKB_MAX_ORDER(0, 0), end - start);
 		struct sk_buff *nskb;
-		unsigned int header = skb_headroom(skb);
-		int copy = SKB_MAX_ORDER(header, 0);
 
-		/* Too big header? This can happen with IPv6. */
-		if (copy < 0)
-			return;
-		if (end - start < copy)
-			copy = end - start;
-		nskb = alloc_skb(copy + header, GFP_ATOMIC);
+		nskb = alloc_skb(copy, GFP_ATOMIC);
 		if (!nskb)
 			return;
 
-		skb_set_mac_header(nskb, skb_mac_header(skb) - skb->head);
-		skb_set_network_header(nskb, (skb_network_header(skb) -
-					      skb->head));
-		skb_set_transport_header(nskb, (skb_transport_header(skb) -
-						skb->head));
-		skb_reserve(nskb, header);
-		memcpy(nskb->head, skb->head, header);
 		memcpy(nskb->cb, skb->cb, sizeof(skb->cb));
 		TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start;
 		__skb_queue_before(list, skb, nskb);