Merge branch 'master' into for-next

1 files changed, 16 insertions, 2 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 6cb1676e409..b4603cd54fc 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -51,6 +51,7 @@
 #include <linux/skbuff.h>	/* struct sk_buff */
 #include <linux/mm.h>
 #include <linux/security.h>
+#include <linux/slab.h>
 
 #include <linux/filter.h>
 #include <linux/rculist_nulls.h>
@@ -253,6 +254,8 @@ struct sock {
 	struct {
 		struct sk_buff *head;
 		struct sk_buff *tail;
+		int len;
+		int limit;
 	} sk_backlog;
 	wait_queue_head_t	*sk_sleep;
 	struct dst_entry	*sk_dst_cache;
@@ -589,8 +592,8 @@ static inline int sk_stream_memory_free(struct sock *sk)
 	return sk->sk_wmem_queued < sk->sk_sndbuf;
 }
 
-/* The per-socket spinlock must be held here. */
-static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
+/* OOB backlog add */
+static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 {
 	if (!sk->sk_backlog.tail) {
 		sk->sk_backlog.head = sk->sk_backlog.tail = skb;
@@ -601,6 +604,17 @@ static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 	skb->next = NULL;
 }
 
+/* The per-socket spinlock must be held here. */
+static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
+{
+	if (sk->sk_backlog.len >= max(sk->sk_backlog.limit, sk->sk_rcvbuf << 1))
+		return -ENOBUFS;
+
+	__sk_add_backlog(sk, skb);
+	sk->sk_backlog.len += skb->truesize;
+	return 0;
+}
+
 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 {
 	return sk->sk_backlog_rcv(sk, skb);