From: Eric Dumazet edumazet@google.com
[ Upstream commit 4c16128b6271e70c8743178e90cccee147858503 ]
At least UDP / TCP stacks can now cook skbs with a tstamp using MONOTONIC base (or arbitrary values with SCM_TXTIME)
Since loopback driver does not call (directly or indirectly) skb_scrub_packet(), we need to clear skb->tstamp so that net_timestamp_check() can eventually resample the time, using ktime_get_real().
Fixes: 80b14dee2bea ("net: Add a new socket option for a future transmit time.") Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet edumazet@google.com Cc: Willem de Bruijn willemb@google.com Cc: Soheil Hassas Yeganeh soheil@google.com Acked-by: Soheil Hassas Yeganeh soheil@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/loopback.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 30612497643c..d192936b76cf 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -75,6 +75,10 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, int len;
skb_tx_timestamp(skb); + + /* do not fool net_timestamp_check() with various clock bases */ + skb->tstamp = 0; + skb_orphan(skb);
/* Before queueing this packet to netif_rx(),