A NET_LOCK() was is missing in tcp_sysctl() which shows up as spl

softnet assert failures.  It is better to place the lock into
net_sysctl() where all the protocol sysctls are called via pr_sysctl.
As calling sysctl(2) is in the slow path, doing fine grained locking
has no benefit.  Many sysctl cases copy out a struct.  Having a
lock around that keeps the struct consistent.  Put assertions in
the protocol sysctls that need it.
OK mpi@

2 files changed, 10 insertions, 17 deletions

diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index 3643cedd8ea..ee25a811a43 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_input.c,v 1.171 2016/12/19 08:36:50 mpi Exp $	*/
+/*	$OpenBSD: ip6_input.c,v 1.172 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $	*/
 
 /*
@@ -1369,7 +1369,9 @@ ip6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 	extern int ip6_mrtproto;
 	extern struct mrt6stat mrt6stat;
 #endif
-	int error, s;
+	int error;
+
+	NET_ASSERT_LOCKED();
 
 	/* Almost all sysctl names at this level are terminal. */
 	if (namelen != 1 && name[0] != IPV6CTL_IFQUEUE)
@@ -1409,12 +1411,9 @@ ip6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 	case IPV6CTL_MTUDISCTIMEOUT:
 		error = sysctl_int(oldp, oldlenp, newp, newlen,
 		   &ip6_mtudisc_timeout);
-		if (icmp6_mtudisc_timeout_q != NULL) {
-			s = splsoftnet();
+		if (icmp6_mtudisc_timeout_q != NULL)
 			rt_timer_queue_change(icmp6_mtudisc_timeout_q,
 					      ip6_mtudisc_timeout);
-			splx(s);
-		}
 		return (error);
 	case IPV6CTL_IFQUEUE:
 		return (sysctl_niq(name + 1, namelen - 1,
diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 0f0c83b2400..cf59c02f31e 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nd6.c,v 1.198 2016/12/19 08:36:50 mpi Exp $	*/
+/*	$OpenBSD: nd6.c,v 1.199 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$KAME: nd6.c,v 1.280 2002/06/08 19:52:07 itojun Exp $	*/
 
 /*
@@ -1639,6 +1639,8 @@ nd6_sysctl(int name, void *oldp, size_t *oldlenp, void *newp, size_t newlen)
 	size_t ol;
 	int error;
 
+	NET_ASSERT_LOCKED();
+
 	error = 0;
 
 	if (newp)
@@ -1678,14 +1680,12 @@ nd6_sysctl(int name, void *oldp, size_t *oldlenp, void *newp, size_t newlen)
 int
 fill_drlist(void *oldp, size_t *oldlenp, size_t ol)
 {
-	int error = 0, s;
+	int error = 0;
 	struct in6_defrouter *d = NULL, *de = NULL;
 	struct nd_defrouter *dr;
 	time_t expire;
 	size_t l;
 
-	s = splsoftnet();
-
 	if (oldp) {
 		d = (struct in6_defrouter *)oldp;
 		de = (struct in6_defrouter *)((caddr_t)oldp + *oldlenp);
@@ -1721,22 +1721,18 @@ fill_drlist(void *oldp, size_t *oldlenp, size_t ol)
 	} else
 		*oldlenp = l;
 
-	splx(s);
-
 	return (error);
 }
 
 int
 fill_prlist(void *oldp, size_t *oldlenp, size_t ol)
 {
-	int error = 0, s;
+	int error = 0;
 	struct nd_prefix *pr;
 	char *p = NULL, *ps = NULL;
 	char *pe = NULL;
 	size_t l;
 
-	s = splsoftnet();
-
 	if (oldp) {
 		ps = p = (char *)oldp;
 		pe = (char *)oldp + *oldlenp;
@@ -1817,7 +1813,5 @@ fill_prlist(void *oldp, size_t *oldlenp, size_t ol)
 	} else
 		*oldlenp = l;
 
-	splx(s);
-
 	return (error);
 }