sock_diag: define destruction multicast groups

These groups will contain socket-destruction events for
AF_INET/AF_INET6, IPPROTO_TCP/IPPROTO_UDP.

Near the end of socket destruction, a check for listeners is
performed.  In the presence of a listener, rather than completely
cleanup the socket, a unit of work will be added to a private
work queue which will first broadcast information about the socket
and then finish the cleanup operation.

Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 1 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index 7063c32..1e1fe9a 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -131,6 +131,7 @@
 #include <linux/ipsec.h>
 #include <net/cls_cgroup.h>
 #include <net/netprio_cgroup.h>
+#include <linux/sock_diag.h>
 
 #include <linux/filter.h>
 
@@ -1423,7 +1424,7 @@ struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
 }
 EXPORT_SYMBOL(sk_alloc);
 
-static void __sk_free(struct sock *sk)
+void sk_destruct(struct sock *sk)
 {
 	struct sk_filter *filter;
 
@@ -1451,6 +1452,14 @@ static void __sk_free(struct sock *sk)
 	sk_prot_free(sk->sk_prot_creator, sk);
 }
 
+static void __sk_free(struct sock *sk)
+{
+	if (unlikely(sock_diag_has_destroy_listeners(sk)))
+		sock_diag_broadcast_destroy(sk);
+	else
+		sk_destruct(sk);
+}
+
 void sk_free(struct sock *sk)
 {
 	/*