tcp: do not leak non zero tstamp in output packets

Usage of skb->tstamp should remain private to TCP stack
(only set on packets on write queue, not on cloned ones)

Otherwise, packets given to loopback interface with a non null tstamp
can confuse netif_rx() / net_timestamp_check()

Other possibility would be to clear tstamp in loopback_xmit(),
as done in skb_scrub_packet()

Fixes: 740b0f1841 ("tcp: switch rtt estimations to usec resolution")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2014-03-05 14:08:38 -08:00 committed by David S. Miller
parent 28f084cca3
commit 2196269242

View File

@ -882,6 +882,8 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
skb = skb_clone(skb, gfp_mask);
if (unlikely(!skb))
return -ENOBUFS;
/* Our usage of tstamp should remain private */
skb->tstamp.tv64 = 0;
}
inet = inet_sk(sk);