From d204af1e414662d5947241d853b4355db116e8f6 Mon Sep 17 00:00:00 2001
From: Ed Maste <emaste@FreeBSD.org>
Date: Wed, 5 Apr 2017 20:11:05 +0000
Subject: [PATCH] bsdgrep: Handle special case of single-byte NUL pattern

PR:		202022
Submitted by:	Kyle Evans <kevans91 at ksu.edu>
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D10102
---
 usr.bin/grep/grep.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/usr.bin/grep/grep.c b/usr.bin/grep/grep.c
index 4961c5b009a2..c9a8d71a3c97 100644
--- a/usr.bin/grep/grep.c
+++ b/usr.bin/grep/grep.c
@@ -314,8 +314,12 @@ read_patterns(const char *fn)
 	}
 	len = 0;
 	line = NULL;
-	while ((rlen = getline(&line, &len, f)) != -1)
+	while ((rlen = getline(&line, &len, f)) != -1) {
+		if (line[0] == '\0')
+			continue;
 		add_pattern(line, line[0] == '\n' ? 0 : (size_t)rlen);
+	}
+
 	free(line);
 	if (ferror(f))
 		err(2, "%s", fn);