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@

7 files changed, 43 insertions, 47 deletions

diff --git a/sys/kern/uipc_domain.c b/sys/kern/uipc_domain.c
index fb0cf9f46dc..34c7aa66e7f 100644
--- a/sys/kern/uipc_domain.c
+++ b/sys/kern/uipc_domain.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_domain.c,v 1.46 2016/11/22 10:32:31 mpi Exp $	*/
+/*	$OpenBSD: uipc_domain.c,v 1.47 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$NetBSD: uipc_domain.c,v 1.14 1996/02/09 19:00:44 christos Exp $	*/
 
 /*
@@ -165,7 +165,7 @@ net_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 {
 	struct domain *dp;
 	struct protosw *pr;
-	int family, protocol;
+	int s, error, family, protocol;
 
 	/*
 	 * All sysctl names at this level are nonterminal.
@@ -199,18 +199,26 @@ net_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 #ifdef MPLS
 	/* XXX WARNING: big fat ugly hack */
 	/* stupid net.mpls is special as it does not have a protocol */
-	if (family == PF_MPLS)
-		return (dp->dom_protosw[0].pr_sysctl(name + 1, namelen - 1,
-		    oldp, oldlenp, newp, newlen));
+	if (family == PF_MPLS) {
+		NET_LOCK(s);
+		error = (dp->dom_protosw[0].pr_sysctl)(name + 1, namelen - 1,
+		    oldp, oldlenp, newp, newlen);
+		NET_UNLOCK(s);
+		return (error);
+	}
 #endif
 
 	if (namelen < 3)
 		return (EISDIR);		/* overloaded */
 	protocol = name[1];
 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
-		if (pr->pr_protocol == protocol && pr->pr_sysctl)
-			return ((*pr->pr_sysctl)(name + 2, namelen - 2,
-			    oldp, oldlenp, newp, newlen));
+		if (pr->pr_protocol == protocol && pr->pr_sysctl) {
+			NET_LOCK(s);
+			error = (*pr->pr_sysctl)(name + 2, namelen - 2,
+			    oldp, oldlenp, newp, newlen);
+			NET_UNLOCK(s);
+			return (error);
+		}
 	return (ENOPROTOOPT);
 }
 
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index 92504f51f3d..d56a8f5cbea 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtsock.c,v 1.211 2016/12/19 08:36:49 mpi Exp $	*/
+/*	$OpenBSD: rtsock.c,v 1.212 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$NetBSD: rtsock.c,v 1.18 1996/03/29 00:32:10 cgd Exp $	*/
 
 /*
@@ -1563,12 +1563,14 @@ int
 sysctl_rtable(int *name, u_int namelen, void *where, size_t *given, void *new,
     size_t newlen)
 {
-	int			 i, s, error = EINVAL;
+	int			 i, error = EINVAL;
 	u_char  		 af;
 	struct walkarg		 w;
 	struct rt_tableinfo	 tableinfo;
 	u_int			 tableid = 0;
 
+	NET_ASSERT_LOCKED();
+
 	if (new)
 		return (EPERM);
 	if (namelen < 3 || namelen > 4)
@@ -1588,7 +1590,6 @@ sysctl_rtable(int *name, u_int namelen, void *where, size_t *given, void *new,
 	} else
 		tableid = curproc->p_p->ps_rtableid;
 
-	s = splsoftnet();
 	switch (w.w_op) {
 	case NET_RT_DUMP:
 	case NET_RT_FLAGS:
@@ -1611,25 +1612,20 @@ sysctl_rtable(int *name, u_int namelen, void *where, size_t *given, void *new,
 	case NET_RT_STATS:
 		error = sysctl_rdstruct(where, given, new,
 		    &rtstat, sizeof(rtstat));
-		splx(s);
 		return (error);
 	case NET_RT_TABLE:
 		tableid = w.w_arg;
-		if (!rtable_exists(tableid)) {
-			splx(s);
+		if (!rtable_exists(tableid))
 			return (ENOENT);
-		}
 		tableinfo.rti_tableid = tableid;
 		tableinfo.rti_domainid = rtable_l2(tableid);
 		error = sysctl_rdstruct(where, given, new,
 		    &tableinfo, sizeof(tableinfo));
-		splx(s);
 		return (error);
 	case NET_RT_IFNAMES:
 		error = sysctl_ifnames(&w);
 		break;
 	}
-	splx(s);
 	free(w.w_tmem, M_RTABLE, 0);
 	w.w_needed += w.w_given;
 	if (where) {
diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c
index 56df4adc6d0..35db6be43ea 100644
--- a/sys/netinet/ip_icmp.c
+++ b/sys/netinet/ip_icmp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_icmp.c,v 1.158 2016/12/19 08:36:49 mpi Exp $	*/
+/*	$OpenBSD: ip_icmp.c,v 1.159 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$NetBSD: ip_icmp.c,v 1.19 1996/02/13 23:42:22 christos Exp $	*/
 
 /*
@@ -878,13 +878,14 @@ int
 icmp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
     size_t newlen)
 {
-	int s, error;
+	int error;
+
+	NET_ASSERT_LOCKED();
 
 	/* All sysctl names at this level are terminal. */
 	if (namelen != 1)
 		return (ENOTDIR);
 
-	NET_LOCK(s);
 	switch (name[0]) {
 	case ICMPCTL_REDIRTIMEOUT:
 
@@ -921,7 +922,6 @@ icmp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		error = ENOPROTOOPT;
 		break;
 	}
-	NET_UNLOCK(s);
 
 	return (error);
 }
diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index c03b2ae39ac..5243e38b6b3 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_input.c,v 1.290 2016/12/19 09:22:24 rzalamena Exp $	*/
+/*	$OpenBSD: ip_input.c,v 1.291 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$NetBSD: ip_input.c,v 1.30 1996/03/16 23:53:58 christos Exp $	*/
 
 /*
@@ -1557,12 +1557,14 @@ int
 ip_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
     size_t newlen) 
 {
-	int s, error;
+	int error;
 #ifdef MROUTING
 	extern int ip_mrtproto;
 	extern struct mrtstat mrtstat;
 #endif
 
+	NET_ASSERT_LOCKED();
+
 	/* Almost all sysctl names at this level are terminal. */
 	if (namelen != 1 && name[0] != IPCTL_IFQUEUE)
 		return (ENOTDIR);
@@ -1587,21 +1589,16 @@ ip_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 			ip_mtudisc_timeout_q =
 			    rt_timer_queue_create(ip_mtudisc_timeout);
 		} else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) {
-			NET_LOCK(s);
 			rt_timer_queue_destroy(ip_mtudisc_timeout_q);
 			ip_mtudisc_timeout_q = NULL;
-			NET_UNLOCK(s);
 		}
 		return error;
 	case IPCTL_MTUDISCTIMEOUT:
 		error = sysctl_int(oldp, oldlenp, newp, newlen,
 		   &ip_mtudisc_timeout);
-		if (ip_mtudisc_timeout_q != NULL) {
-			NET_LOCK(s);
+		if (ip_mtudisc_timeout_q != NULL)
 			rt_timer_queue_change(ip_mtudisc_timeout_q,
 					      ip_mtudisc_timeout);
-			NET_UNLOCK(s);
-		}
 		return (error);
 	case IPCTL_IPSEC_ENC_ALGORITHM:
 	        return (sysctl_tstring(oldp, oldlenp, newp, newlen,
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
index ed781bafdd7..5cd71d38c04 100644
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tcp_usrreq.c,v 1.138 2016/12/20 14:10:00 mpi Exp $	*/
+/*	$OpenBSD: tcp_usrreq.c,v 1.139 2016/12/20 18:33:43 bluhm Exp $	*/
 /*	$NetBSD: tcp_usrreq.c,v 1.20 1996/02/13 23:44:16 christos Exp $	*/
 
 /*
@@ -846,6 +846,8 @@ tcp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 {
 	int error, nval;
 
+	NET_ASSERT_LOCKED();
+
 	/* All sysctl names at this level are terminal. */
 	if (namelen != 1)
 		return (ENOTDIR);
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);
 }