diff options
| author | Lance Richardson <lrichard@redhat.com> | 2016-11-02 21:36:17 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-11-03 21:10:26 +0100 |
| commit | 9ee6c5dc816aa8256257f2cd4008a9291ec7e985 (patch) | |
| tree | b52ae6938861f8a9ce99c46db958b28a7ac321fd /net/ipv4/ip_forward.c | |
| parent | net: tcp: check skb is non-NULL for exact match on lookups (diff) | |
| download | linux-9ee6c5dc816aa8256257f2cd4008a9291ec7e985.tar.xz linux-9ee6c5dc816aa8256257f2cd4008a9291ec7e985.zip | |
ipv4: allow local fragmentation in ip_finish_output_gso()
Some configurations (e.g. geneve interface with default
MTU of 1500 over an ethernet interface with 1500 MTU) result
in the transmission of packets that exceed the configured MTU.
While this should be considered to be a "bad" configuration,
it is still allowed and should not result in the sending
of packets that exceed the configured MTU.
Fix by dropping the assumption in ip_finish_output_gso() that
locally originated gso packets will never need fragmentation.
Basic testing using iperf (observing CPU usage and bandwidth)
have shown no measurable performance impact for traffic not
requiring fragmentation.
Fixes: c7ba65d7b649 ("net: ip: push gso skb forwarding handling down the stack")
Reported-by: Jan Tluka <jtluka@redhat.com>
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_forward.c')
| -rw-r--r-- | net/ipv4/ip_forward.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 8b4ffd216839..9f0a7b96646f 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -117,7 +117,7 @@ int ip_forward(struct sk_buff *skb) if (opt->is_strictroute && rt->rt_uses_gateway) goto sr_failed; - IPCB(skb)->flags |= IPSKB_FORWARDED | IPSKB_FRAG_SEGS; + IPCB(skb)->flags |= IPSKB_FORWARDED; mtu = ip_dst_mtu_maybe_forward(&rt->dst, true); if (ip_exceeds_mtu(skb, mtu)) { IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); |