From 711fe4468e09a42d4276e7a2465b476e1fd18191 Mon Sep 17 00:00:00 2001
From: thorpej <thorpej@NetBSD.org>
Date: Sat, 26 May 2018 21:15:46 +0000
Subject: [PATCH] Avoid dereferencing NULL if we attempt to look up an known
 unit type.

---
 sys/dev/sysmon/sysmon_envsys.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sys/dev/sysmon/sysmon_envsys.c b/sys/dev/sysmon/sysmon_envsys.c
index c957041465ef..b46059f9744b 100644
--- a/sys/dev/sysmon/sysmon_envsys.c
+++ b/sys/dev/sysmon/sysmon_envsys.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: sysmon_envsys.c,v 1.142 2018/05/05 00:14:28 pgoyette Exp $	*/
+/*	$NetBSD: sysmon_envsys.c,v 1.143 2018/05/26 21:15:46 thorpej Exp $	*/
 
 /*-
  * Copyright (c) 2007, 2008 Juan Romero Pardines.
@@ -64,7 +64,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sysmon_envsys.c,v 1.142 2018/05/05 00:14:28 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sysmon_envsys.c,v 1.143 2018/05/26 21:15:46 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -578,7 +578,7 @@ sysmon_envsys_sensor_attach(struct sysmon_envsys *sme, envsys_data_t *edata)
 	 * Find the correct units for this sensor.
 	 */
 	sdt_units = sme_find_table_entry(SME_DESC_UNITS, edata->units);
-	if (sdt_units->type == -1)
+	if (sdt_units == NULL || sdt_units->type == -1)
 		return EINVAL;
 
 	/*