net/ipv6/udp: UDP encapsulation: move socket locking into udpv6_queue_rcv_skb()

[linux-beck.git] / net / ipv6 / udp.c

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 37b0699e95e5331dffb186f6971411d2d16c88c8..bc533ea8fc686a92af2dd4806392bba899652dc2 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -496,6 +496,28 @@ out:
        sock_put(sk);
 }
 
+static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+       int rc;
+
+       if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
+               sock_rps_save_rxhash(sk, skb);
+
+       rc = sock_queue_rcv_skb(sk, skb);
+       if (rc < 0) {
+               int is_udplite = IS_UDPLITE(sk);
+
+               /* Note that an ENOMEM error is charged twice */
+               if (rc == -ENOMEM)
+                       UDP6_INC_STATS_BH(sock_net(sk),
+                                       UDP_MIB_RCVBUFERRORS, is_udplite);
+               UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+               kfree_skb(skb);
+               return -1;
+       }
+       return 0;
+}
+
 static __inline__ void udpv6_err(struct sk_buff *skb,
                                 struct inet6_skb_parm *opt, u8 type,
                                 u8 code, int offset, __be32 info     )
@@ -503,15 +525,12 @@ static __inline__ void udpv6_err(struct sk_buff *skb,
        __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
 }
 
-int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
+int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
        struct udp_sock *up = udp_sk(sk);
        int rc;
        int is_udplite = IS_UDPLITE(sk);
 
-       if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
-               sock_rps_save_rxhash(sk, skb);
-
        if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
                goto drop;
 
@@ -539,21 +558,25 @@ int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                        goto drop;
        }
 
+       if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
+               goto drop;
+
        skb_dst_drop(skb);
-       rc = sock_queue_rcv_skb(sk, skb);
-       if (rc < 0) {
-               /* Note that an ENOMEM error is charged twice */
-               if (rc == -ENOMEM)
-                       UDP6_INC_STATS_BH(sock_net(sk),
-                                       UDP_MIB_RCVBUFERRORS, is_udplite);
-               goto drop_no_sk_drops_inc;
+
+       bh_lock_sock(sk);
+       rc = 0;
+       if (!sock_owned_by_user(sk))
+               rc = __udpv6_queue_rcv_skb(sk, skb);
+       else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
+               bh_unlock_sock(sk);
+               goto drop;
        }
+       bh_unlock_sock(sk);
 
-       return 0;
+       return rc;
 drop:
-       atomic_inc(&sk->sk_drops);
-drop_no_sk_drops_inc:
        UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+       atomic_inc(&sk->sk_drops);
        kfree_skb(skb);
        return -1;
 }
@@ -602,37 +625,27 @@ static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
 static void flush_stack(struct sock **stack, unsigned int count,
                        struct sk_buff *skb, unsigned int final)
 {
-       unsigned int i;
+       struct sk_buff *skb1 = NULL;
        struct sock *sk;
-       struct sk_buff *skb1;
+       unsigned int i;
 
        for (i = 0; i < count; i++) {
-               skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
-
                sk = stack[i];
-               if (skb1) {
-                       if (sk_rcvqueues_full(sk, skb1)) {
-                               kfree_skb(skb1);
-                               goto drop;
-                       }
-                       bh_lock_sock(sk);
-                       if (!sock_owned_by_user(sk))
-                               udpv6_queue_rcv_skb(sk, skb1);
-                       else if (sk_add_backlog(sk, skb1)) {
-                               kfree_skb(skb1);
-                               bh_unlock_sock(sk);
-                               goto drop;
-                       }
-                       bh_unlock_sock(sk);
-                       continue;
+               if (likely(skb1 == NULL))
+                       skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
+               if (!skb1) {
+                       atomic_inc(&sk->sk_drops);
+                       UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
+                                         IS_UDPLITE(sk));
+                       UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
+                                         IS_UDPLITE(sk));
                }
-drop:
-               atomic_inc(&sk->sk_drops);
-               UDP6_INC_STATS_BH(sock_net(sk),
-                               UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk));
-               UDP6_INC_STATS_BH(sock_net(sk),
-                               UDP_MIB_INERRORS, IS_UDPLITE(sk));
+
+               if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
+                       skb1 = NULL;
        }
+       if (unlikely(skb1))
+               kfree_skb(skb1);
 }
 /*
  * Note: called only from the BH handler context,
@@ -772,39 +785,29 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
         * for sock caches... i'll skip this for now.
         */
        sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
+       if (sk != NULL) {
+               int ret = udpv6_queue_rcv_skb(sk, skb);
+               sock_put(sk);
 
-       if (sk == NULL) {
-               if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
-                       goto discard;
-
-               if (udp_lib_checksum_complete(skb))
-                       goto discard;
-               UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS,
-                               proto == IPPROTO_UDPLITE);
-
-               icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
+               /* a return value > 0 means to resubmit the input, but
+                * it wants the return to be -protocol, or 0
+                */
+               if (ret > 0)
+                       return -ret;
 
-               kfree_skb(skb);
                return 0;
        }
 
-       /* deliver */
-
-       if (sk_rcvqueues_full(sk, skb)) {
-               sock_put(sk);
+       if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
                goto discard;
-       }
-       bh_lock_sock(sk);
-       if (!sock_owned_by_user(sk))
-               udpv6_queue_rcv_skb(sk, skb);
-       else if (sk_add_backlog(sk, skb)) {
-               atomic_inc(&sk->sk_drops);
-               bh_unlock_sock(sk);
-               sock_put(sk);
+
+       if (udp_lib_checksum_complete(skb))
                goto discard;
-       }
-       bh_unlock_sock(sk);
-       sock_put(sk);
+
+       UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
+       icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
+
+       kfree_skb(skb);
        return 0;
 
 short_packet:
@@ -1471,7 +1474,7 @@ struct proto udpv6_prot = {
        .getsockopt        = udpv6_getsockopt,
        .sendmsg           = udpv6_sendmsg,
        .recvmsg           = udpv6_recvmsg,
-       .backlog_rcv       = udpv6_queue_rcv_skb,
+       .backlog_rcv       = __udpv6_queue_rcv_skb,
        .hash              = udp_lib_hash,
        .unhash            = udp_lib_unhash,
        .rehash            = udp_v6_rehash,