If an ip6 tunnel is configured to inherit the traffic class from
the inner header, the dst_cache must be disabled or it will foul
the policy routing.
The issue is apprently there since at leat Linux-2.6.12-rc2.
Reported-by: Liam McBirnie <liam.mcbir...@boeing.com>
Cc: Liam McBirnie <liam.mcbir...@boeing.com>
Acked-by: Hannes Frederic Sowa <han...@stressinduktion.org>
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
net/ipv6/ip6_tunnel.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 8778456..0a4759b 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1034,6 +1034,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device
*dev, __u8 dsfield,
int mtu;
unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
unsigned int max_headroom = psh_hlen;
+ bool use_cache = false;
u8 hop_limit;
int err = -1;
@@ -1066,7 +1067,15 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device
*dev, __u8 dsfield,
memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
neigh_release(neigh);
- } else if (!fl6->flowi6_mark)
+ } else if (!(t->parms.flags &
+ (IP6_TNL_F_USE_ORIG_TCLASS | IP6_TNL_F_USE_ORIG_FWMARK))) {
+ /* enable the cache only only if the routing decision does
+ * not depend on the current inner header value
+ */
+ use_cache = true;
+ }
+
+ if (use_cache)
dst = dst_cache_get(&t->dst_cache);
if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
@@ -1150,7 +1159,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device
*dev, __u8 dsfield,
if (t->encap.type != TUNNEL_ENCAP_NONE)
goto tx_err_dst_release;
} else {
- if (!fl6->flowi6_mark && ndst)
+ if (use_cache && ndst)
dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
}
skb_dst_set(skb, dst);
--
1.8.3.1
