From: kettenis <kettenis@openbsd.org>
Date: Wed, 19 May 2021 18:10:45 +0000 (+0000)
Subject: In ttyinfo() check that ps_vmspace isn't NULL before calculating the
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=2c417a9eed782cc86302610b11dd2650081be304;p=openbsd

In ttyinfo() check that ps_vmspace isn't NULL before calculating the
resident set size.  This replicates what the sysctl code does and fixes
a kernel crash reported by robert@

ok deraadt@
---

diff --git a/sys/kern/tty.c b/sys/kern/tty.c
index 169c3d1cdf7..7f41b2bf923 100644
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tty.c,v 1.168 2021/05/16 15:10:20 deraadt Exp $	*/
+/*	$OpenBSD: tty.c,v 1.169 2021/05/19 18:10:45 kettenis Exp $	*/
 /*	$NetBSD: tty.c,v 1.68.4.2 1996/06/06 16:04:52 thorpej Exp $	*/
 
 /*-
@@ -2157,7 +2157,7 @@ empty:		ttyprintf(tp, "empty foreground process group\n");
 		fixpt_t pctcpu, pctcpu2;
 		int run, run2;
 		int calc_pctcpu;
-		long rss;
+		long rss = 0;
 
 		/*
 		 * Pick the most active process:
@@ -2194,8 +2194,9 @@ update_pickpr:
 
 		/* Calculate percentage cpu, resident set size. */
 		calc_pctcpu = (pctcpu * 10000 + FSCALE / 2) >> FSHIFT;
-		rss = (pickpr->ps_flags & (PS_EMBRYO | PS_ZOMBIE)) ? 0 :
-		    vm_resident_count(pickpr->ps_vmspace);
+		if ((pickpr->ps_flags & (PS_EMBRYO | PS_ZOMBIE)) == 0 &&
+		    pickpr->ps_vmspace != NULL)
+			rss = vm_resident_count(pickpr->ps_vmspace);
 
 		calctsru(&pickpr->ps_tu, &utime, &stime, NULL);