From b4adfcf2f4ae75ca472941bff0eef710ec3b6abe Mon Sep 17 00:00:00 2001
From: Brian Feldman <green@FreeBSD.org>
Date: Fri, 11 Jun 2004 02:20:37 +0000
Subject: [PATCH] Make sysctl_wire_old_buffer() respect ENOMEM from vslock() by
 marking the valid length as 0.  This prevents vsunlock() from removing a
 system wire from memory that was not successfully wired (by us).

Submitted by:	tegge
---
 sys/kern/kern_sysctl.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 79e99a664a2..39214de4d0c 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1101,8 +1101,11 @@ sysctl_wire_old_buffer(struct sysctl_req *req, size_t len)
 	    req->oldfunc == sysctl_old_user) {
 		if (wiredlen != 0) {
 			ret = vslock(req->oldptr, wiredlen);
-			if (ret != 0 && ret != ENOMEM)
-				return (ret);
+			if (ret != 0) {
+				if (ret != ENOMEM)
+					return (ret);
+				wiredlen = 0;
+			}
 		}
 		req->lock = REQ_WIRED;
 		req->validlen = wiredlen;