From 219626924222b6b41bf2264896b34a6abaaeecf0 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 5 Mar 2014 14:08:38 -0800 Subject: [PATCH] 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: 740b0f1841f6 ("tcp: switch rtt estimations to usec resolution") Signed-off-by: Eric Dumazet Reported-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/ipv4/tcp_output.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index a02c884d4321..bc0fb0fc7552 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -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); -- 2.30.2