udp: use limited socket backlog

Make udp adapt to the limited socket backlog change.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 608a5446d05b..e7eb47f338d4 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1371,8 +1371,10 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
         bh_lock_sock(sk);
         if (!sock_owned_by_user(sk))
                 rc = __udp_queue_rcv_skb(sk, skb);
-        else
-                sk_add_backlog(sk, skb);
+        else if (sk_add_backlog_limited(sk, skb)) {
+                bh_unlock_sock(sk);
+                goto drop;
+        }
         bh_unlock_sock(sk);
 
         return rc;