2 files changed, 3 insertions, 0 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index e11eaf4cc269..a091a99ad263 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -504,6 +504,7 @@ void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
         if (skb->ip_summed == CHECKSUM_PARTIAL) {
                 th->check = ~tcp_v4_check(len, inet->saddr,
                                           inet->daddr, 0);
+                skb->csum_start = skb_transport_header(skb) - skb->head;
                 skb->csum_offset = offsetof(struct tcphdr, check);
         } else {
                 th->check = tcp_v4_check(len, inet->saddr, inet->daddr,
@@ -526,6 +527,7 @@ int tcp_v4_gso_send_check(struct sk_buff *skb)
 
         th->check = 0;
         th->check = ~tcp_v4_check(skb->len, iph->saddr, iph->daddr, 0);
+        skb->csum_start = skb_transport_header(skb) - skb->head;
         skb->csum_offset = offsetof(struct tcphdr, check);
         skb->ip_summed = CHECKSUM_PARTIAL;
         return 0;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 71b0b60ba538..5ad7a26e3091 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -427,6 +427,7 @@ static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
                 /*
                  * Only one fragment on the socket.
                  */
+                skb->csum_start = skb_transport_header(skb) - skb->head;
                 skb->csum_offset = offsetof(struct udphdr, check);
                 uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0);
         } else {