[PATCH 3.12 28/38] ip6_tunnel: disable caching when the traffic class is inherited
From: Jiri Slaby <hidden>
Date: 2016-12-13 19:55:14
Also in:
lkml
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
From: Paolo Abeni <pabeni@redhat.com> 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 <redacted> Cc: Liam McBirnie <redacted> Acked-by: Hannes Frederic Sowa <redacted> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jiri Slaby <redacted> --- 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