From c3d5404bbe9b51c8373832a220b2568fc8b806fe Mon Sep 17 00:00:00 2001
From: gnn <gnn@FreeBSD.org>
Date: Thu, 24 Mar 2016 07:54:56 +0000
Subject: FreeBSD previously provided route caching for TCP (and UDP). Re-add
 route caching for TCP, with some improvements. In particular, invalidate the
 route cache if a new route is added, which might be a better match. The cache
 is automatically invalidated if the old route is deleted.

Submitted by:	Mike Karels
Reviewed by:	gnn
Differential Revision:	https://reviews.freebsd.org/D4306
---
 sys/netinet/udp_usrreq.c | 42 ++++++++++++++++++++++++++++++------------
 1 file changed, 30 insertions(+), 12 deletions(-)

(limited to 'sys/netinet/udp_usrreq.c')

diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index f474a54..ecd1e0c 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -740,6 +740,11 @@ udp_notify(struct inpcb *inp, int errno)
 	 * or a write lock, but a read lock is sufficient.
 	 */
 	INP_LOCK_ASSERT(inp);
+	if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
+	     errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
+		RTFREE(inp->inp_route.ro_rt);
+		inp->inp_route.ro_rt = (struct rtentry *)NULL;
+	}
 
 	inp->inp_socket->so_error = errno;
 	sorwakeup(inp->inp_socket);
@@ -761,11 +766,11 @@ udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 	if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 		return;
 
-	/*
-	 * Redirects don't need to be handled up here.
-	 */
-	if (PRC_IS_REDIRECT(cmd))
+	if (PRC_IS_REDIRECT(cmd)) {
+		/* signal EHOSTDOWN, as it flushes the cached route */
+		in_pcbnotifyall(&udbinfo, faddr, EHOSTDOWN, udp_notify);
 		return;
+	}
 
 	/*
 	 * Hostdead is ugly because it goes linearly through all PCBs.
@@ -1116,7 +1121,7 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 	int error = 0;
 	int ipflags;
 	u_short fport, lport;
-	int unlock_udbinfo;
+	int unlock_udbinfo, unlock_inp;
 	u_char tos;
 	uint8_t pr;
 	uint16_t cscov = 0;
@@ -1137,7 +1142,15 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 	}
 
 	src.sin_family = 0;
-	INP_RLOCK(inp);
+	sin = (struct sockaddr_in *)addr;
+	if (sin == NULL ||
+	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
+		INP_WLOCK(inp);
+		unlock_inp = UH_WLOCKED;
+	} else {
+		INP_RLOCK(inp);
+		unlock_inp = UH_RLOCKED;
+	}
 	tos = inp->inp_ip_tos;
 	if (control != NULL) {
 		/*
@@ -1145,7 +1158,10 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 		 * stored in a single mbuf.
 		 */
 		if (control->m_next) {
-			INP_RUNLOCK(inp);
+			if (unlock_inp == UH_WLOCKED)
+				INP_WUNLOCK(inp);
+			else
+				INP_RUNLOCK(inp);
 			m_freem(control);
 			m_freem(m);
 			return (EINVAL);
@@ -1220,7 +1236,10 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 		m_freem(control);
 	}
 	if (error) {
-		INP_RUNLOCK(inp);
+		if (unlock_inp == UH_WLOCKED)
+			INP_WUNLOCK(inp);
+		else
+			INP_RUNLOCK(inp);
 		m_freem(m);
 		return (error);
 	}
@@ -1246,8 +1265,6 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 	sin = (struct sockaddr_in *)addr;
 	if (sin != NULL &&
 	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
-		INP_RUNLOCK(inp);
-		INP_WLOCK(inp);
 		INP_HASH_WLOCK(pcbinfo);
 		unlock_udbinfo = UH_WLOCKED;
 	} else if ((sin != NULL && (
@@ -1514,9 +1531,10 @@ udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 	else if (unlock_udbinfo == UH_RLOCKED)
 		INP_HASH_RUNLOCK(pcbinfo);
 	UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
-	error = ip_output(m, inp->inp_options, NULL, ipflags,
+	error = ip_output(m, inp->inp_options,
+	    (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
 	    inp->inp_moptions, inp);
-	if (unlock_udbinfo == UH_WLOCKED)
+	if (unlock_inp == UH_WLOCKED)
 		INP_WUNLOCK(inp);
 	else
 		INP_RUNLOCK(inp);
-- 
cgit v1.1


From a460d0156798a8e88ab4f60947b9180e7a9c13b5 Mon Sep 17 00:00:00 2001
From: bz <bz@FreeBSD.org>
Date: Thu, 24 Mar 2016 11:40:10 +0000
Subject: Fix compile errors after r297225:

- properly V_irtualise variable access unbreaking VIMAGE kernels.
- remove the volatile from the function return type to make architecture
  using gcc happy [-Wreturn-type]
  "type qualifiers ignored on function return type"
  I am not entirely happy with this solution putting the u_int there
  but it will do for now.
---
 sys/netinet/udp_usrreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'sys/netinet/udp_usrreq.c')

diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index ecd1e0c..56aa56f 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -768,7 +768,7 @@ udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 
 	if (PRC_IS_REDIRECT(cmd)) {
 		/* signal EHOSTDOWN, as it flushes the cached route */
-		in_pcbnotifyall(&udbinfo, faddr, EHOSTDOWN, udp_notify);
+		in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 		return;
 	}
 
-- 
cgit v1.1