path: root/net/ipv4/ip_input.c
diff options
authorThomas Graf <tgraf@suug.ch>2015-07-21 10:43:56 +0200
committerDavid S. Miller <davem@davemloft.net>2015-07-21 10:39:05 -0700
commitf38a9eb1f77b296ff07e000823884a0f64d67b2a (patch)
treef1404a06ffc6ce0f2bfc8a24e12a1faa7bc0db57 /net/ipv4/ip_input.c
parenticmp: Don't leak original dst into ip_route_input() (diff)
dst: Metadata destinations
Introduces a new dst_metadata which enables to carry per packet metadata between forwarding and processing elements via the skb->dst pointer. The structure is set up to be a union. Thus, each separate type of metadata requires its own dst instance. If demand arises to carry multiple types of metadata concurrently, metadata dst entries can be made stackable. The metadata dst entry is refcnt'ed as expected for now but a non reference counted use is possible if the reference is forced before queueing the skb. In order to allow allocating dsts with variable length, the existing dst_alloc() is split into a dst_alloc() and dst_init() function. The existing dst_init() function to initialize the subsystem is being renamed to dst_subsys_init() to make it clear what is what. The check before ip_route_input() is changed to ignore metadata dsts and drop the dst inside the routing function thus allowing to interpret metadata in a later commit. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 2db4c8773c1b..f4fc8a77aaa7 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -146,6 +146,7 @@
#include <net/xfrm.h>
#include <linux/mroute.h>
#include <linux/netlink.h>
+#include <net/dst_metadata.h>
* Process Router Attention IP option (RFC 2113)
@@ -331,7 +332,7 @@ static int ip_rcv_finish(struct sock *sk, struct sk_buff *skb)
* Initialise the virtual path cache for the packet. It describes
* how the packet travels inside Linux networking.
- if (!skb_dst(skb)) {
+ if (!skb_valid_dst(skb)) {
int err = ip_route_input_noref(skb, iph->daddr, iph->saddr,
iph->tos, skb->dev);
if (unlikely(err)) {