ipv6: only apply anti-spoofing checks to not-pointopoint tunnels

[ Upstream commit 5c29fb12e8fb8a8105ea048cb160fd79a85a52bb ]

Because of commit 218774dc341f219bfcf940304a081b121a0e8099 ("ipv6: add
anti-spoofing checks for 6to4 and 6rd") the sit driver dropped packets
for 2002::/16 destinations and sources even when configured to work as a
tunnel with fixed endpoint. We may only apply the 6rd/6to4 anti-spoofing
checks if the device is not in pointopoint mode.

This was an oversight from me in the above commit, sorry.  Thanks to
Roman Mamedov for reporting this!

Reported-by: Roman Mamedov <rm@romanrm.ru>
Cc: David Miller <davem@davemloft.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 335363478bbf..60df36d15390 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -589,7 +589,7 @@ static int ipip6_rcv(struct sk_buff *skb)
                                 tunnel->dev->stats.rx_errors++;
                                 goto out;
                         }
-                } else {
+                } else if (!(tunnel->dev->flags&IFF_POINTOPOINT)) {
                         if (is_spoofed_6rd(tunnel, iph->saddr,
                                            &ipv6_hdr(skb)->saddr) ||
                             is_spoofed_6rd(tunnel, iph->daddr,