ipv4: mentions skb_gro_postpull_rcsum() in inet_gro_receive()

Proper CHECKSUM_COMPLETE support needs to adjust skb->csum
when we remove one header. Its done using skb_gro_postpull_rcsum()

In the case of IPv4, we know that the adjustment is not really needed,
because the checksum over IPv4 header is 0. Lets add a comment to
ease code comprehension and avoid copy/paste errors.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 28e589c5f32d..92db7a69f2b9 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1369,6 +1369,9 @@ static struct sk_buff **inet_gro_receive(struct sk_buff **head,
          * immediately following this IP hdr.
          */
 
+        /* Note : No need to call skb_gro_postpull_rcsum() here,
+         * as we already checked checksum over ipv4 header was 0
+         */
         skb_gro_pull(skb, sizeof(*iph));
         skb_set_transport_header(skb, skb_gro_offset(skb));