From 017a5e581a4eabf0ba0d10ea5bb168ce0e00946a Mon Sep 17 00:00:00 2001
From: "Andrey V. Elsukov" <ae@FreeBSD.org>
Date: Sun, 11 Mar 2018 19:14:01 +0000
Subject: [PATCH] Rework key_sendup_mbuf() a bit:

o count in_nomem counter when we have failed to allocate mbuf for
  promisc socket;
o count in_msgtarget counter when we have secussfully sent data to socket;
o Since we are sending messages in a loop, returning error on first fail
  interrupts the loop, and all remaining sockets will not receive this
  message. So, do not return error when we have failed to send data to ALL
  or REGISTERED target. Return error only for KEY_SENDUP_ONE case. Now,
  when some socket has overfilled its receive buffer, this will not break
  other sockets.

MFC after:	2 weeks
---
 sys/netipsec/keysock.c | 60 ++++++++++++++----------------------------
 1 file changed, 20 insertions(+), 40 deletions(-)

diff --git a/sys/netipsec/keysock.c b/sys/netipsec/keysock.c
index fc17113992e8..7f8b0e51c59e 100644
--- a/sys/netipsec/keysock.c
+++ b/sys/netipsec/keysock.c
@@ -178,7 +178,6 @@ key_sendup_mbuf(struct socket *so, struct mbuf *m, int target)
 {
 	struct mbuf *n;
 	struct keycb *kp;
-	int sendup;
 	struct rawcb *rp;
 	int error = 0;
 
@@ -217,69 +216,50 @@ key_sendup_mbuf(struct socket *so, struct mbuf *m, int target)
 			continue;
 		}
 
-		kp = (struct keycb *)rp;
-
 		/*
 		 * If you are in promiscuous mode, and when you get broadcasted
 		 * reply, you'll get two PF_KEY messages.
 		 * (based on pf_key@inner.net message on 14 Oct 1998)
 		 */
-		if (((struct keycb *)rp)->kp_promisc) {
-			if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
-				(void)key_sendup0(rp, n, 1);
-				n = NULL;
-			}
+		kp = (struct keycb *)rp;
+		if (kp->kp_promisc) {
+			n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
+			if (n != NULL)
+				key_sendup0(rp, n, 1);
+			else
+				PFKEYSTAT_INC(in_nomem);
 		}
 
 		/* the exact target will be processed later */
 		if (so && sotorawcb(so) == rp)
 			continue;
 
-		sendup = 0;
-		switch (target) {
-		case KEY_SENDUP_ONE:
-			/* the statement has no effect */
-			if (so && sotorawcb(so) == rp)
-				sendup++;
-			break;
-		case KEY_SENDUP_ALL:
-			sendup++;
-			break;
-		case KEY_SENDUP_REGISTERED:
-			if (kp->kp_registered)
-				sendup++;
-			break;
-		}
-		PFKEYSTAT_INC(in_msgtarget[target]);
-
-		if (!sendup)
+		if (target == KEY_SENDUP_ONE || (
+		    target == KEY_SENDUP_REGISTERED && kp->kp_registered == 0))
 			continue;
 
-		if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) {
-			m_freem(m);
+		/* KEY_SENDUP_ALL + KEY_SENDUP_REGISTERED */
+		n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
+		if (n == NULL) {
 			PFKEYSTAT_INC(in_nomem);
-			mtx_unlock(&rawcb_mtx);
-			return ENOBUFS;
+			/* Try send to another socket */
+			continue;
 		}
 
-		if ((error = key_sendup0(rp, n, 0)) != 0) {
-			m_freem(m);
-			mtx_unlock(&rawcb_mtx);
-			return error;
-		}
-
-		n = NULL;
+		if (key_sendup0(rp, n, 0) == 0)
+			PFKEYSTAT_INC(in_msgtarget[target]);
 	}
 
-	if (so) {
+	if (so)	{ /* KEY_SENDUP_ONE */
 		error = key_sendup0(sotorawcb(so), m, 0);
-		m = NULL;
+		if (error == 0)
+			PFKEYSTAT_INC(in_msgtarget[KEY_SENDUP_ONE]);
 	} else {
 		error = 0;
 		m_freem(m);
 	}
 	mtx_unlock(&rawcb_mtx);
-	return error;
+	return (error);
 }
 
 /*