From 4283ce49aaeff967bb51251766311ad963ae0496 Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Wed, 27 Apr 2016 14:08:01 +0200 Subject: [PATCH] gre: reject GUE and FOU in collect metadata mode commit 946b636f1730c64e05ff7fe8cf7136422fa8ea70 upstream. The collect metadata mode does not support GUE nor FOU. This might be implemented later; until then, we should reject such config. I think this is okay to be changed. It's unlikely anyone has such configuration (as it doesn't work anyway) and we may need a way to distinguish whether it's supported or not by the kernel later. For backwards compatibility with iproute2, it's not possible to just check the attribute presence (iproute2 always includes the attribute), the actual value has to be checked, too. Fixes: 2e15ea390e6f4 ("ip_gre: Add support to collect tunnel metadata.") Signed-off-by: Jiri Benc Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_gre.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index f42af9460823..e5448570d648 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -937,6 +937,11 @@ static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) if (flags & (GRE_VERSION|GRE_ROUTING)) return -EINVAL; + if (data[IFLA_GRE_COLLECT_METADATA] && + data[IFLA_GRE_ENCAP_TYPE] && + nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) + return -EINVAL; + return 0; }