From: Paolo Abeni <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== [ Upstream commit b5c2d49544e5930c96e2632a7eece3f4325a1888 ] 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 <[email protected]> Cc: Liam McBirnie <[email protected]> Acked-by: Hannes Frederic Sowa <[email protected]> Signed-off-by: Paolo Abeni <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- 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 cfdb663e0259..9a625b1ae10f 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -950,12 +950,21 @@ static int ip6_tnl_xmit2(struct sk_buff *skb, struct ipv6_tel_txoption opt; struct dst_entry *dst = NULL, *ndst = NULL; struct net_device *tdev; + bool use_cache = false; int mtu; unsigned int max_headroom = sizeof(struct ipv6hdr); u8 proto; int err = -1; - if (!fl6->flowi6_mark) + 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 = ip6_tnl_dst_check(t); if (!dst) { ndst = ip6_route_output(net, NULL, fl6); @@ -1013,7 +1022,7 @@ static int ip6_tnl_xmit2(struct sk_buff *skb, consume_skb(skb); skb = new_skb; } - if (fl6->flowi6_mark) { + if (!use_cache) { skb_dst_set(skb, dst); ndst = NULL; } else { -- 2.11.0
