net/ipv6/udp: UDP encapsulation: move socket locking into udpv6_queue_rcv_skb()
In order to make sure that when the encap_rcv() hook is introduced it is
not called with the socket lock held, move socket locking from callers into
udpv6_queue_rcv_skb(), matching what happens in IPv4.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 6c0367f..bc533ea 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -558,14 +558,25 @@
goto drop;
}
+ if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
+ goto drop;
+
skb_dst_drop(skb);
- rc = __udpv6_queue_rcv_skb(sk, skb);
+ 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 rc;
drop:
- atomic_inc(&sk->sk_drops);
UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+ atomic_inc(&sk->sk_drops);
kfree_skb(skb);
return -1;
}
@@ -614,37 +625,27 @@
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, sk->sk_rcvbuf)) {
- 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, sk->sk_rcvbuf)) {
- 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,
@@ -784,39 +785,29 @@
* 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;
+ /* a return value > 0 means to resubmit the input, but
+ * it wants the return to be -protocol, or 0
+ */
+ if (ret > 0)
+ return -ret;
- 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);
-
- kfree_skb(skb);
return 0;
}
- /* deliver */
+ if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+ goto discard;
- if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
- sock_put(sk);
+ if (udp_lib_checksum_complete(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, sk->sk_rcvbuf)) {
- atomic_inc(&sk->sk_drops);
- bh_unlock_sock(sk);
- sock_put(sk);
- 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: