inet: Don't lookup the socket if there's a socket attached to the skb

Use the socket cached in the skb if it's present.

Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 75a312d3888a..18f96708f3a6 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1324,6 +1324,18 @@ static inline void sk_change_net(struct sock *sk, struct net *net)
         sock_net_set(sk, hold_net(net));
 }
 
+static inline struct sock *skb_steal_sock(struct sk_buff *skb)
+{
+        if (unlikely(skb->sk)) {
+                struct sock *sk = skb->sk;
+
+                skb->destructor = NULL;
+                skb->sk = NULL;
+                return sk;
+        }
+        return NULL;
+}
+
 extern void sock_enable_timestamp(struct sock *sk);
 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
 extern int sock_get_timestampns(struct sock *, struct timespec __user *);