From f74da371592dbe1e09495f48e79e77ec170a2c46 Mon Sep 17 00:00:00 2001
From: mvs <mvs@openbsd.org>
Date: Wed, 12 May 2021 08:09:33 +0000
Subject: [PATCH] Use local copy of `ps_rtableid' in ip{,6}_ctloutput() and
 mark `ps_rtableid' as atomic. This allows us to unlock setrtable(2).

ok claudio@ mpi@
---
 sys/netinet/ip_output.c   | 9 +++++----
 sys/netinet6/ip6_output.c | 9 +++++----
 sys/sys/proc.h            | 4 ++--
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index e9e41517e7b..396caa3ea13 100644
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_output.c,v 1.370 2021/03/30 08:37:11 sashan Exp $	*/
+/*	$OpenBSD: ip_output.c,v 1.371 2021/05/12 08:09:33 mvs Exp $	*/
 /*	$NetBSD: ip_output.c,v 1.28 1996/02/13 23:43:07 christos Exp $	*/
 
 /*
@@ -856,11 +856,13 @@ ip_ctloutput(int op, struct socket *so, int level, int optname,
 	int optval = 0;
 	struct proc *p = curproc; /* XXX */
 	int error = 0;
-	u_int rtid = 0;
+	u_int rtableid, rtid = 0;
 
 	if (level != IPPROTO_IP)
 		return (EINVAL);
 
+	rtableid = p->p_p->ps_rtableid;
+
 	switch (op) {
 	case PRCO_SETOPT:
 		switch (optname) {
@@ -1050,8 +1052,7 @@ ip_ctloutput(int op, struct socket *so, int level, int optname,
 			if (inp->inp_rtableid == rtid)
 				break;
 			/* needs privileges to switch when already set */
-			if (p->p_p->ps_rtableid != rtid &&
-			    p->p_p->ps_rtableid != 0 &&
+			if (rtableid != rtid && rtableid != 0 &&
 			    (error = suser(p)) != 0)
 				break;
 			/* table must exist */
diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index 28ed1c4aef2..e11ac43961b 100644
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_output.c,v 1.256 2021/03/10 10:21:49 jsg Exp $	*/
+/*	$OpenBSD: ip6_output.c,v 1.257 2021/05/12 08:09:33 mvs Exp $	*/
 /*	$KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $	*/
 
 /*
@@ -1059,7 +1059,7 @@ ip6_ctloutput(int op, struct socket *so, int level, int optname,
 	struct inpcb *inp = sotoinpcb(so);
 	int error, optval;
 	struct proc *p = curproc; /* For IPsec and rdomain */
-	u_int rtid = 0;
+	u_int rtableid, rtid = 0;
 
 	error = optval = 0;
 
@@ -1069,6 +1069,8 @@ ip6_ctloutput(int op, struct socket *so, int level, int optname,
 	if (level != IPPROTO_IPV6)
 		return (EINVAL);
 
+	rtableid = p->p_p->ps_rtableid;
+
 	switch (op) {
 	case PRCO_SETOPT:
 		switch (optname) {
@@ -1363,8 +1365,7 @@ do { \
 			if (inp->inp_rtableid == rtid)
 				break;
 			/* needs privileges to switch when already set */
-			if (p->p_p->ps_rtableid != rtid &&
-			    p->p_p->ps_rtableid != 0 &&
+			if (rtableid != rtid && rtableid != 0 &&
 			    (error = suser(p)) != 0)
 				break;
 			/* table must exist */
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 80585795c28..75ae18c541c 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.h,v 1.311 2021/03/17 14:06:54 visa Exp $	*/
+/*	$OpenBSD: proc.h,v 1.312 2021/05/12 08:09:33 mvs Exp $	*/
 /*	$NetBSD: proc.h,v 1.44 1996/04/22 01:23:21 christos Exp $	*/
 
 /*-
@@ -251,7 +251,7 @@ struct process {
 	vaddr_t	ps_sigcode;		/* User pointer to the signal code */
 	vaddr_t ps_sigcoderet;		/* User pointer to sigreturn retPC */
 	u_long	ps_sigcookie;
-	u_int	ps_rtableid;		/* Process routing table/domain. */
+	u_int	ps_rtableid;		/* [a] Process routing table/domain. */
 	char	ps_nice;		/* Process "nice" value. */
 
 	struct uprof {			/* profile arguments */
-- 
2.20.1