From a0a5c4c7ecb0e50cbaced67d943f45bbf11374c5 Mon Sep 17 00:00:00 2001
From: mvs <mvs@openbsd.org>
Date: Thu, 18 May 2023 09:59:43 +0000
Subject: [PATCH] Revert ip_sysctl() unlocking. Lock order issue was triggered
 in UVM layer.

---
 sys/kern/uipc_domain.c | 8 +++-----
 sys/netinet/in_proto.c | 3 +--
 sys/netinet/ip_input.c | 9 +++------
 sys/sys/protosw.h      | 4 +---
 4 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/sys/kern/uipc_domain.c b/sys/kern/uipc_domain.c
index aa38e09d03a..ba9a69b96bd 100644
--- a/sys/kern/uipc_domain.c
+++ b/sys/kern/uipc_domain.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_domain.c,v 1.62 2023/05/16 19:36:00 mvs Exp $	*/
+/*	$OpenBSD: uipc_domain.c,v 1.63 2023/05/18 09:59:43 mvs Exp $	*/
 /*	$NetBSD: uipc_domain.c,v 1.14 1996/02/09 19:00:44 christos Exp $	*/
 
 /*
@@ -244,12 +244,10 @@ net_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 	protocol = name[1];
 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
 		if (pr->pr_protocol == protocol && pr->pr_sysctl) {
-			if ((pr->pr_flags & PR_MPSYSCTL) == 0)
-				KERNEL_LOCK();
+			KERNEL_LOCK();
 			error = (*pr->pr_sysctl)(name + 2, namelen - 2,
 			    oldp, oldlenp, newp, newlen);
-			if ((pr->pr_flags & PR_MPSYSCTL) == 0)
-				KERNEL_UNLOCK();
+			KERNEL_UNLOCK();
 			return (error);
 		}
 	return (ENOPROTOOPT);
diff --git a/sys/netinet/in_proto.c b/sys/netinet/in_proto.c
index 2a49df55c5d..526596eb6b8 100644
--- a/sys/netinet/in_proto.c
+++ b/sys/netinet/in_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_proto.c,v 1.100 2023/05/16 19:36:00 mvs Exp $	*/
+/*	$OpenBSD: in_proto.c,v 1.101 2023/05/18 09:59:43 mvs Exp $	*/
 /*	$NetBSD: in_proto.c,v 1.14 1996/02/18 18:58:32 christos Exp $	*/
 
 /*
@@ -177,7 +177,6 @@ u_char ip_protox[IPPROTO_MAX];
 const struct protosw inetsw[] = {
 {
   .pr_domain	= &inetdomain,
-  .pr_flags	= PR_MPSYSCTL,
   .pr_init	= ip_init,
   .pr_slowtimo	= ip_slowtimo,
   .pr_sysctl	= ip_sysctl
diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index cfa703cca3e..31c8a8eaf54 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_input.c,v 1.384 2023/05/16 19:36:00 mvs Exp $	*/
+/*	$OpenBSD: ip_input.c,v 1.385 2023/05/18 09:59:43 mvs Exp $	*/
 /*	$NetBSD: ip_input.c,v 1.30 1996/03/16 23:53:58 christos Exp $	*/
 
 /*
@@ -1704,11 +1704,8 @@ ip_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		return (ip_sysctl_ipstat(oldp, oldlenp, newp));
 #ifdef MROUTING
 	case IPCTL_MRTSTATS:
-		KERNEL_LOCK();
-		error = sysctl_rdstruct(oldp, oldlenp, newp,
-		    &mrtstat, sizeof(mrtstat));
-		KERNEL_UNLOCK();
-		return (error);
+		return (sysctl_rdstruct(oldp, oldlenp, newp,
+		    &mrtstat, sizeof(mrtstat)));
 	case IPCTL_MRTMFC:
 		if (newp)
 			return (EPERM);
diff --git a/sys/sys/protosw.h b/sys/sys/protosw.h
index 0456d320c05..bf17e7b78a8 100644
--- a/sys/sys/protosw.h
+++ b/sys/sys/protosw.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: protosw.h,v 1.61 2023/05/16 19:44:55 mvs Exp $	*/
+/*	$OpenBSD: protosw.h,v 1.62 2023/05/18 09:59:44 mvs Exp $	*/
 /*	$NetBSD: protosw.h,v 1.10 1996/04/09 20:55:32 cgd Exp $	*/
 
 /*-
@@ -131,8 +131,6 @@ struct protosw {
 #define PR_ABRTACPTDIS	0x0020		/* abort on accept(2) to disconnected
 					   socket */
 #define PR_SPLICE	0x0040		/* socket splicing is possible */
-#define PR_MPSYSCTL	0x0080		/* (*pr_sysctl)() doesn't require
-					   kernel lock */
 
 /*
  * The arguments to usrreq are:
-- 
2.20.1