Going forward skb_dst_set will assert that skb dst_entry
is empty during skb_dst_set. skb_dstref_steal is added to reset
existing entry without doing refcnt. Switch to skb_dstref_steal
in ip[6]_route_me_harder and add a comment on why it's safe
to skip skb_dstref_restore.
Acked-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxxx>
---
net/ipv4/netfilter.c | 5 ++++-
net/ipv6/netfilter.c | 5 ++++-
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c
index 0565f001120d..e60e54e7945d 100644
--- a/net/ipv4/netfilter.c
+++ b/net/ipv4/netfilter.c
@@ -65,7 +65,10 @@ int ip_route_me_harder(struct net *net, struct sock *sk, struct sk_buff *skb, un
if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
xfrm_decode_session(net, skb, flowi4_to_flowi(&fl4), AF_INET) == 0) {
struct dst_entry *dst = skb_dst(skb);
- skb_dst_set(skb, NULL);
+ /* ignore return value from skb_dstref_steal, xfrm_lookup takes
+ * care of dropping the refcnt if needed.
+ */
+ skb_dstref_steal(skb);
dst = xfrm_lookup(net, dst, flowi4_to_flowi(&fl4), sk, 0);
if (IS_ERR(dst))
return PTR_ERR(dst);
diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c
index 45f9105f9ac1..46540a5a4331 100644
--- a/net/ipv6/netfilter.c
+++ b/net/ipv6/netfilter.c
@@ -63,7 +63,10 @@ int ip6_route_me_harder(struct net *net, struct sock *sk_partial, struct sk_buff
#ifdef CONFIG_XFRM
if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
xfrm_decode_session(net, skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
- skb_dst_set(skb, NULL);
+ /* ignore return value from skb_dstref_steal, xfrm_lookup takes
+ * care of dropping the refcnt if needed.
+ */
+ skb_dstref_steal(skb);
dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
if (IS_ERR(dst))
return PTR_ERR(dst);
--
2.50.1
