Commit 8203e2d8 authored Dec 14, 2018 by Eric Dumazet Committed by David S. Miller Dec 15, 2018

net: clear skb->tstamp in forwarding paths



Sergey reported that forwarding was no longer working
if fq packet scheduler was used.

This is caused by the recent switch to EDT model, since incoming
packets might have been timestamped by __net_timestamp()

__net_timestamp() uses ktime_get_real(), while fq expects packets
using CLOCK_MONOTONIC base.

The fix is to clear skb->tstamp in forwarding paths.

Fixes: 80b14dee ("net: Add a new socket option for a future transmit time.")
Fixes: fb420d5d ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Sergey Matyukevich <geomatsi@gmail.com>
Tested-by: Sergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 15c6d8e5

net/ipv4/ip_forward.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -72,6 +72,7 @@ static int ip_forward_finish(struct net net, struct sock sk, struct sk_buff *s
		if (unlikely(opt->optlen))
		ip_forward_options(skb);

		skb->tstamp = 0;
		return dst_output(net, sk, skb);
		}

net/ipv6/ip6_output.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -378,6 +378,7 @@ static inline int ip6_forward_finish(struct net net, struct sock sk,
		__IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
		__IP6_ADD_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len);

		skb->tstamp = 0;
		return dst_output(net, sk, skb);
		}

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