From 5dbd073b045c8e98730c025a4acf2279be26c33e Mon Sep 17 00:00:00 2001
From: Ed Maste <emaste@FreeBSD.org>
Date: Fri, 14 Apr 2023 10:49:05 -0400
Subject: [PATCH] awk: errror on printf format strings lacking conversion
 specifier

Reported by:	phk
Reviewed by:	imp, markj
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D39573
---
 contrib/one-true-awk/run.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/contrib/one-true-awk/run.c b/contrib/one-true-awk/run.c
index 117fb0748bd8..b81dafba35e6 100644
--- a/contrib/one-true-awk/run.c
+++ b/contrib/one-true-awk/run.c
@@ -912,6 +912,9 @@ int format(char **pbuf, int *pbufsize, const char *s, Node *a)	/* printf-like co
 		case 'c':
 			flag = 'c';
 			break;
+		case '\0':
+			FATAL("missing printf conversion specifier");
+			break;
 		default:
 			WARNING("weird printf conversion %s", fmt);
 			flag = '?';