diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index c83938b8fcb1201ddf403c6423cd83790397595b..f745095196f7bbd4fb10c7032fb669187e0f5574 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -578,7 +578,7 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
 	struct tcphdr *th = skb->h.th;
 	struct {
 		struct tcphdr th;
-		u32 tsopt[3];
+		u32 tsopt[TCPOLEN_TSTAMP_ALIGNED >> 2];
 	} rep;
 	struct ip_reply_arg arg;
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 3b6575478fcc381aae64ee2c0d7b2b791d5f1846..34e004bdeab0fa94dab33ffd1eada1a39ef00b92 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -653,7 +653,7 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32
 	int tot_len = sizeof(struct tcphdr);
 
 	if (ts)
-		tot_len += 3*4;
+		tot_len += TCPOLEN_TSTAMP_ALIGNED;
 
 	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
 			 GFP_ATOMIC);