udp: Drop socket lock for encapsulated packets

The socket lock is there to protect the normal UDP receive path.
Encapsulation UDP sockets don't need that protection.  In fact
the locking is deadly for them as they may contain another UDP
packet within, possibly with the same addresses.

Also the nested bit was copied from TCP.  TCP needs it because
of accept(2) spawning sockets.  This simply doesn't apply to UDP
so I've removed it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 383d17359d01f1a81080df5aabef22266c1dd1c4..8e42fbbd57616316df2692a39379398f9486ac22 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -989,7 +989,9 @@ int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                    up->encap_rcv != NULL) {
                        int ret;
 
+                       bh_unlock_sock(sk);
                        ret = (*up->encap_rcv)(sk, skb);
+                       bh_lock_sock(sk);
                        if (ret <= 0) {
                                UDP_INC_STATS_BH(sock_net(sk),
                                                 UDP_MIB_INDATAGRAMS,
@@ -1092,7 +1094,7 @@ static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
                        if (skb1) {
                                int ret = 0;
 
-                               bh_lock_sock_nested(sk);
+                               bh_lock_sock(sk);
                                if (!sock_owned_by_user(sk))
                                        ret = udp_queue_rcv_skb(sk, skb1);
                                else
@@ -1194,7 +1196,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
 
        if (sk != NULL) {
                int ret = 0;
-               bh_lock_sock_nested(sk);
+               bh_lock_sock(sk);
                if (!sock_owned_by_user(sk))
                        ret = udp_queue_rcv_skb(sk, skb);
                else

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index d1477b350f761aa474f47c7444d3327d0a19bbe1..a6aecf76a71bb05eb8a551e52217fbcaa93d6035 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -379,7 +379,7 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
                                        uh->source, saddr, dif))) {
                struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC);
                if (buff) {
-                       bh_lock_sock_nested(sk2);
+                       bh_lock_sock(sk2);
                        if (!sock_owned_by_user(sk2))
                                udpv6_queue_rcv_skb(sk2, buff);
                        else
@@ -387,7 +387,7 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
                        bh_unlock_sock(sk2);
                }
        }
-       bh_lock_sock_nested(sk);
+       bh_lock_sock(sk);
        if (!sock_owned_by_user(sk))
                udpv6_queue_rcv_skb(sk, skb);
        else
@@ -508,7 +508,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
 
        /* deliver */
 
-       bh_lock_sock_nested(sk);
+       bh_lock_sock(sk);
        if (!sock_owned_by_user(sk))
                udpv6_queue_rcv_skb(sk, skb);
        else