Chance protocol switch method pru_detach() so that it returns void

rather than an error.  Detaches do not "fail", they other occur or
the protocol flags SS_PROTOREF to take ownership of the socket.

soclose() no longer looks at so_pcb to see if it's NULL, relying
entirely on the protocol to decide whether it's time to free the
socket or not using SS_PROTOREF.  so_pcb is now entirely owned and
managed by the protocol code.  Likewise, no longer test so_pcb in
other socket functions, such as soreceive(), which have no business
digging into protocol internals.

Protocol detach routines no longer try to free the socket on detach,
this is performed in the socket code if the protocol permits it.

In rts_detach(), no longer test for rp != NULL in detach, and
likewise in other protocols that don't permit a NULL so_pcb, reduce
the incidence of testing for it during detach.

netinet and netinet6 are not fully updated to this change, which
will be in an upcoming commit.  In their current state they may leak
memory or panic.

MFC after:	3 months

3 files changed, 24 insertions, 30 deletions

diff --git a/sys/net/raw_cb.c b/sys/net/raw_cb.c
index 31566d1..f45be72 100644
--- a/sys/net/raw_cb.c
+++ b/sys/net/raw_cb.c
@@ -98,10 +98,9 @@ raw_detach(rp)
 {
 	struct socket *so = rp->rcb_socket;
 
-	ACCEPT_LOCK();
-	SOCK_LOCK(so);
-	so->so_pcb = 0;
-	sotryfree(so);
+	KASSERT(so->so_pcb == rp, ("raw_detach: so_pcb != rp"));
+
+	so->so_pcb = NULL;
 	mtx_lock(&rawcb_mtx);
 	LIST_REMOVE(rp, list);
 	mtx_unlock(&rawcb_mtx);
diff --git a/sys/net/raw_usrreq.c b/sys/net/raw_usrreq.c
index c6f1a7d..300dd91 100644
--- a/sys/net/raw_usrreq.c
+++ b/sys/net/raw_usrreq.c
@@ -178,16 +178,15 @@ raw_uconnect(struct socket *so, struct sockaddr *nam, struct thread *td)
 /* pru_connect2 is EOPNOTSUPP */
 /* pru_control is EOPNOTSUPP */
 
-static int
+static void
 raw_udetach(struct socket *so)
 {
 	struct rawcb *rp = sotorawcb(so);
 
 	if (rp == 0)
-		return EINVAL;
+		return;
 
 	raw_detach(rp);
-	return 0;
 }
 
 static int
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index ad64ef0..701662d 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -152,8 +152,8 @@ rts_attach(struct socket *so, int proto, struct thread *td)
 	struct rawcb *rp;
 	int s, error;
 
-	if (sotorawcb(so) != NULL)
-		return EISCONN;	/* XXX panic? */
+	KASSERT(so->so_pcb == NULL, ("rts_attach: so_pcb != NULL"));
+
 	/* XXX */
 	MALLOC(rp, struct rawcb *, sizeof *rp, M_PCB, M_WAITOK | M_ZERO);
 	if (rp == NULL)
@@ -214,32 +214,28 @@ rts_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 /* pru_connect2 is EOPNOTSUPP */
 /* pru_control is EOPNOTSUPP */
 
-static int
+static void
 rts_detach(struct socket *so)
 {
 	struct rawcb *rp = sotorawcb(so);
-	int s, error;
 
-	s = splnet();
-	if (rp != NULL) {
-		RTSOCK_LOCK();
-		switch(rp->rcb_proto.sp_protocol) {
-		case AF_INET:
-			route_cb.ip_count--;
-			break;
-		case AF_INET6:
-			route_cb.ip6_count--;
-			break;
-		case AF_IPX:
-			route_cb.ipx_count--;
-			break;
-		}
-		route_cb.any_count--;
-		RTSOCK_UNLOCK();
+	KASSERT(rp != NULL, ("rts_detach: rp == NULL"));
+
+	RTSOCK_LOCK();
+	switch(rp->rcb_proto.sp_protocol) {
+	case AF_INET:
+		route_cb.ip_count--;
+		break;
+	case AF_INET6:
+		route_cb.ip6_count--;
+		break;
+	case AF_IPX:
+		route_cb.ipx_count--;
+		break;
 	}
-	error = raw_usrreqs.pru_detach(so);
-	splx(s);
-	return error;
+	route_cb.any_count--;
+	RTSOCK_UNLOCK();
+	raw_usrreqs.pru_detach(so);
 }
 
 static int