From 24e4f21763343acbc1867b4c983b782d4781283a Mon Sep 17 00:00:00 2001
From: delphij <delphij@FreeBSD.org>
Date: Tue, 24 Jan 2017 07:48:36 +0000
Subject: [PATCH] Don't reference NULL pointer.

MFC after:	2 weeks
---
 usr.bin/mail/popen.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/usr.bin/mail/popen.c b/usr.bin/mail/popen.c
index 9cd4378245d4..7326f51bb64e 100644
--- a/usr.bin/mail/popen.c
+++ b/usr.bin/mail/popen.c
@@ -303,7 +303,7 @@ findchild(pid_t pid, int dont_alloc)
 	    cpp = &(*cpp)->link)
 			;
 	if (*cpp == NULL) {
-	if (dont_alloc)
+		if (dont_alloc)
 			return(NULL);
 		if (child_freelist) {
 			*cpp = child_freelist;
@@ -344,6 +344,8 @@ sigchild(int signo __unused)
 	save_errno = errno;
 	while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
 		cp = findchild(pid, 1);
+		if (cp == NULL)
+			continue;
 		if (cp->free)
 			delchild(cp);
 		else {