From 49e9fc0a0d531c10d024ae0501ce56d9f19a74c9 Mon Sep 17 00:00:00 2001
From: Poul-Henning Kamp <phk@FreeBSD.org>
Date: Fri, 2 Jan 2004 19:02:28 +0000
Subject: [PATCH] Improve on POLA by populating DEVFS before doing devfs(8)
 rule ioctls.

PR:	60687
Spotted by:	Colin Percival <cperciva@daemonology.net>
---
 sys/fs/devfs/devfs_vnops.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c
index c9e6ad105b5..8f03714d5f4 100644
--- a/sys/fs/devfs/devfs_vnops.c
+++ b/sys/fs/devfs/devfs_vnops.c
@@ -279,7 +279,12 @@ devfs_ioctl(ap)
 	} */ *ap;
 {
 	int error;
+	struct devfs_mount *dmp;
 
+	dmp = VFSTODEVFS(ap->a_vp->v_mount);
+	lockmgr(&dmp->dm_lock, LK_SHARED, 0, curthread);
+	devfs_populate(dmp);
+	lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread);
 	error = devfs_rules_ioctl(ap->a_vp->v_mount, ap->a_command, ap->a_data,
 	    ap->a_td);
 	return (error);