tcp: refresh skb timestamp at retransmit time

In the very unlikely case __tcp_retransmit_skb() can not use the cloning done in tcp_transmit_skb(), we need to refresh skb_mstamp before doing the copy and transmit, otherwise TCP TS val will be an exact copy of original transmit. Fixes: 7faee5c ("tcp: remove TCP_SKB_CB(skb)->when") Signed-off-by: Eric Dumazet <[email protected]> Cc: Yuchung Cheng <[email protected]> Acked-by: Yuchung Cheng <[email protected]> Signed-off-by: David S. Miller <[email protected]>
MaxKrummenacher · May 10, 2016 · 10a8198 · 10a8198
1 parent 3b0d190
commit 10a8198
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
@@ -2640,8 +2640,10 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
 	 */
 	if (unlikely((NET_IP_ALIGN && ((unsigned long)skb->data & 3)) ||
 		     skb_headroom(skb) >= 0xFFFF)) {
-		struct sk_buff *nskb = __pskb_copy(skb, MAX_TCP_HEADER,
-						   GFP_ATOMIC);
+		struct sk_buff *nskb;
+
+		skb_mstamp_get(&skb->skb_mstamp);
+		nskb = __pskb_copy(skb, MAX_TCP_HEADER, GFP_ATOMIC);
 		err = nskb ? tcp_transmit_skb(sk, nskb, 0, GFP_ATOMIC) :
 			     -ENOBUFS;
 	} else {