From 5f814682b48c59f07568d349f979eed4cf306703 Mon Sep 17 00:00:00 2001
From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 28 Sep 2011 22:07:58 -0400
Subject: don't crash on null strings in printf

passing null pointer for %s is UB but lots of broken programs do it anyway
---
 src/stdio/vfprintf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdio/vfprintf.c b/src/stdio/vfprintf.c
index 4c990e5e..b5001ff2 100644
--- a/src/stdio/vfprintf.c
+++ b/src/stdio/vfprintf.c
@@ -584,7 +584,7 @@ static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg,
 		case 'm':
 			if (1) a = strerror(errno); else
 		case 's':
-			a = arg.p;
+			a = arg.p ? arg.p : "(null)";
 			z = memchr(a, 0, p);
 			if (!z) z=a+p;
 			else p=z-a;
-- 
cgit v1.2.1