@@ -477,7 +477,16 @@ static inline struct dst_entry *xfrm_lookup(struct net *net,
int flags)
{
return dst_orig;
-}
+}
+
+static inline struct dst_entry *xfrm_lookup_route(struct net *net,
+ struct dst_entry *dst_orig,
+ const struct flowi *fl,
+ struct sock *sk,
+ int flags)
+{
+ return dst_orig;
+}
static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
{
@@ -489,6 +498,10 @@ struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
const struct flowi *fl, struct sock *sk,
int flags);
+struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
+ const struct flowi *fl, struct sock *sk,
+ int flags);
+
/* skb attached with this dst needs transformation if dst->xfrm is valid */
static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
{
@@ -2270,9 +2270,9 @@ struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
return rt;
if (flp4->flowi4_proto)
- rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
- flowi4_to_flowi(flp4),
- sk, 0);
+ rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst,
+ flowi4_to_flowi(flp4),
+ sk, 0);
return rt;
}
@@ -991,7 +991,7 @@ struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
if (can_sleep)
fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
- return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
+ return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
}
EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
@@ -1027,7 +1027,7 @@ struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
if (can_sleep)
fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
- return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
+ return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
}
EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
@@ -2150,7 +2150,7 @@ restart:
xfrm_pols_put(pols, drop_pols);
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
- return make_blackhole(net, family, dst_orig);
+ return ERR_PTR(-EREMOTE);
}
if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) {
DECLARE_WAITQUEUE(wait, current);
@@ -2222,6 +2222,22 @@ dropdst:
}
EXPORT_SYMBOL(xfrm_lookup);
+/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
+ * Otherwise we may send out blackholed packets.
+ */
+struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
+ const struct flowi *fl,
+ struct sock *sk, int flags)
+{
+ struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, flags);
+
+ if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
+ return make_blackhole(net, dst_orig->ops->family, dst_orig);
+
+ return dst;
+}
+EXPORT_SYMBOL(xfrm_lookup_route);
+
static inline int
xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
{
This is a note to let you know that I have just added a patch titled xfrm: Generate blackhole routes only from route lookup functions to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.11. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 7705ff4112e432c6dbbefa39a0428ca3d6caf897 Mon Sep 17 00:00:00 2001 From: Steffen Klassert <steffen.klassert@secunet.com> Date: Tue, 16 Sep 2014 10:08:40 +0200 Subject: xfrm: Generate blackhole routes only from route lookup functions [ Upstream commit f92ee61982d6da15a9e49664ecd6405a15a2ee56 ] Currently we genarate a blackhole route route whenever we have matching policies but can not resolve the states. Here we assume that dst_output() is called to kill the balckholed packets. Unfortunately this assumption is not true in all cases, so it is possible that these packets leave the system unwanted. We fix this by generating blackhole routes only from the route lookup functions, here we can guarantee a call to dst_output() afterwards. Fixes: 2774c131b1d ("xfrm: Handle blackhole route creation via afinfo.") Reported-by: Konstantinos Kolelis <k.kolelis@sirrix.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- include/net/dst.h | 15 ++++++++++++++- net/ipv4/route.c | 6 +++--- net/ipv6/ip6_output.c | 4 ++-- net/xfrm/xfrm_policy.c | 18 +++++++++++++++++- 4 files changed, 36 insertions(+), 7 deletions(-) -- 1.9.1