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| author | David S. Miller <davem@davemloft.net> | 2019-12-24 22:28:55 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-12-24 22:28:55 -0800 |
| commit | 47d0b2fe23d840ecbfc187d9ef0ee9e1a229a332 (patch) | |
| tree | d45b1c2d62ee09cf5b45f1ea9f6f2a9d17aacccb /include | |
| parent | ff43ae4bd5aab8acd3a4a9cf49a2a99cbb1719fb (diff) | |
| parent | f081042d128a0c7acbd67611def62e1b52e2d294 (diff) | |
Merge branch 'disable-neigh-update-for-tunnels-during-pmtu-update'
Hangbin Liu says:
====================
disable neigh update for tunnels during pmtu update
When we setup a pair of gretap, ping each other and create neighbour cache.
Then delete and recreate one side. We will never be able to ping6 to the new
created gretap.
The reason is when we ping6 remote via gretap, we will call like
gre_tap_xmit()
- ip_tunnel_xmit()
- tnl_update_pmtu()
- skb_dst_update_pmtu()
- ip6_rt_update_pmtu()
- __ip6_rt_update_pmtu()
- dst_confirm_neigh()
- ip6_confirm_neigh()
- __ipv6_confirm_neigh()
- n->confirmed = now
As the confirmed time updated, in neigh_timer_handler() the check for
NUD_DELAY confirm time will pass and the neigh state will back to
NUD_REACHABLE. So the old/wrong mac address will be used again.
If we do not update the confirmed time, the neigh state will go to
neigh->nud_state = NUD_PROBE; then go to NUD_FAILED and re-create the
neigh later, which is what IPv4 does.
We couldn't remove the ip6_confirm_neigh() directly as we still need it
for TCP flows. To fix it, we have to pass a bool parameter to
dst_ops.update_pmtu() and only disable neighbor update for tunnels.
v5: No code change, upate some commits description
v4: No code change, upate some commits description
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
dst_ops.update_pmtu to control whether we should do neighbor confirm.
Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/dst.h | 13 | ||||
| -rw-r--r-- | include/net/dst_ops.h | 3 |
2 files changed, 13 insertions, 3 deletions
diff --git a/include/net/dst.h b/include/net/dst.h index 8224dad2ae94..3448cf865ede 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -516,7 +516,16 @@ static inline void skb_dst_update_pmtu(struct sk_buff *skb, u32 mtu) struct dst_entry *dst = skb_dst(skb); if (dst && dst->ops->update_pmtu) - dst->ops->update_pmtu(dst, NULL, skb, mtu); + dst->ops->update_pmtu(dst, NULL, skb, mtu, true); +} + +/* update dst pmtu but not do neighbor confirm */ +static inline void skb_dst_update_pmtu_no_confirm(struct sk_buff *skb, u32 mtu) +{ + struct dst_entry *dst = skb_dst(skb); + + if (dst && dst->ops->update_pmtu) + dst->ops->update_pmtu(dst, NULL, skb, mtu, false); } static inline void skb_tunnel_check_pmtu(struct sk_buff *skb, @@ -526,7 +535,7 @@ static inline void skb_tunnel_check_pmtu(struct sk_buff *skb, u32 encap_mtu = dst_mtu(encap_dst); if (skb->len > encap_mtu - headroom) - skb_dst_update_pmtu(skb, encap_mtu - headroom); + skb_dst_update_pmtu_no_confirm(skb, encap_mtu - headroom); } #endif /* _NET_DST_H */ diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h index 5ec645f27ee3..443863c7b8da 100644 --- a/include/net/dst_ops.h +++ b/include/net/dst_ops.h @@ -27,7 +27,8 @@ struct dst_ops { struct dst_entry * (*negative_advice)(struct dst_entry *); void (*link_failure)(struct sk_buff *); void (*update_pmtu)(struct dst_entry *dst, struct sock *sk, - struct sk_buff *skb, u32 mtu); + struct sk_buff *skb, u32 mtu, + bool confirm_neigh); void (*redirect)(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb); int (*local_out)(struct net *net, struct sock *sk, struct sk_buff *skb); |