Fix a regression introduced in r179289 splitting up ip6_savecontrol()

into v4-only vs. v6-only inp_flags processing.
When ip6_savecontrol_v4() is called from ip6_savecontrol() we
were not passing back the **mp thus the information will be missing
in userland.
Istead of going with a *** as suggested in the PR we are returning
**mp now and passing in the v4only flag as a pointer argument.

PR:		kern/126349
Reviewed by:	rwatson, dwmalone

3 files changed, 17 insertions, 8 deletions

diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index 715599e..c9cf5d4 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -216,7 +216,7 @@ udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 	    inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 #ifdef INET6
 		if (inp->inp_vflag & INP_IPV6)
-			ip6_savecontrol_v4(inp, n, &opts);
+			(void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 		else
 #endif
 			ip_savecontrol(inp, &opts, ip, n);
diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index 7b4e4dc..e6ca375 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -1042,8 +1042,9 @@ ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
  * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
  * options and handle the v6-only ones itself.
  */
-int
-ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp)
+struct mbuf **
+ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
+    int *v4only)
 {
 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 
@@ -1059,8 +1060,11 @@ ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp)
 	}
 #endif
 
-	if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION)
-		return (1);
+	if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
+		if (v4only != NULL)
+			*v4only = 1;
+		return (mp);
+	}
 
 #define IS2292(inp, x, y)	(((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
 	/* RFC 2292 sec. 5 */
@@ -1089,15 +1093,19 @@ ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp)
 			mp = &(*mp)->m_next;
 	}
 
-	return (0);
+	if (v4only != NULL)
+		*v4only = 0;
+	return (mp);
 }
 
 void
 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp)
 {
 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
+	int v4only = 0;
 
-	if (ip6_savecontrol_v4(in6p, m, mp) != 0)
+	mp = ip6_savecontrol_v4(in6p, m, mp, &v4only);
+	if (v4only)
 		return;
 
 	if ((in6p->in6p_flags & IN6P_TCLASS) != 0) {
diff --git a/sys/netinet6/ip6_var.h b/sys/netinet6/ip6_var.h
index 2370737..f13ea34 100644
--- a/sys/netinet6/ip6_var.h
+++ b/sys/netinet6/ip6_var.h
@@ -350,7 +350,8 @@ extern int	(*ip6_mforward)(struct ip6_hdr *, struct ifnet *,
 
 int	ip6_process_hopopts __P((struct mbuf *, u_int8_t *, int, u_int32_t *,
 				 u_int32_t *));
-int	ip6_savecontrol_v4(struct inpcb *, struct mbuf *, struct mbuf **);
+struct mbuf	**ip6_savecontrol_v4(struct inpcb *, struct mbuf *,
+	    struct mbuf **, int *);
 void	ip6_savecontrol __P((struct inpcb *, struct mbuf *, struct mbuf **));
 void	ip6_notify_pmtu __P((struct inpcb *, struct sockaddr_in6 *,
 			     u_int32_t *));