diff options
| author | Shmulik Ladkani <shmulik.ladkani@gmail.com> | 2016-06-29 21:47:03 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-06-30 09:02:48 -0400 |
| commit | fedbb6b4ff341c1e2120f4ffbf367fd78ac3e8f3 (patch) | |
| tree | aec9b6ddce0a103d82704f52a693f1d3cd238dbb /include/net/ip.h | |
| parent | 5ab0d6a016b19d8cbd503eafd0ef701cfd854402 (diff) | |
ipv4: Fix ip_skb_dst_mtu to use the sk passed by ip_finish_output
ip_skb_dst_mtu uses skb->sk, assuming it is an AF_INET socket (e.g. it
calls ip_sk_use_pmtu which casts sk as an inet_sk).
However, in the case of UDP tunneling, the skb->sk is not necessarily an
inet socket (could be AF_PACKET socket, or AF_UNSPEC if arriving from
tun/tap).
OTOH, the sk passed as an argument throughout IP stack's output path is
the one which is of PMTU interest:
- In case of local sockets, sk is same as skb->sk;
- In case of a udp tunnel, sk is the tunneling socket.
Fix, by passing ip_finish_output's sk to ip_skb_dst_mtu.
This augments 7026b1ddb6 'netfilter: Pass socket pointer down through okfn().'
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/ip.h')
| -rw-r--r-- | include/net/ip.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/include/net/ip.h b/include/net/ip.h index 37165fba3741..08f36cd2b874 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -313,10 +313,9 @@ static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, return min(dst->dev->mtu, IP_MAX_MTU); } -static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb) +static inline unsigned int ip_skb_dst_mtu(struct sock *sk, + const struct sk_buff *skb) { - struct sock *sk = skb->sk; - if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; |