Francois Gouget : winetest: Avoid an infinite loop in vstrfmtmake() when the format is NULL.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: cac02872c6f3d8c286cfdb6201b200a6c5fa24ee
URL:    https://gitlab.winehq.org/wine/wine/-/commit/cac02872c6f3d8c286cfdb6201b200a...

Author: Francois Gouget <fgouget(a)codeweavers.com>
Date:   Mon Feb 13 19:17:57 2023 +0100

winetest: Avoid an infinite loop in vstrfmtmake() when the format is NULL.

When the format is NULL vsnprintf() always returns -1 so we keep
doubling the allocated memory until running out of memory.

---

 programs/winetest/util.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/programs/winetest/util.c b/programs/winetest/util.c
index a1320005841..bd5b584c3c4 100644
--- a/programs/winetest/util.c
+++ b/programs/winetest/util.c
@@ -56,6 +56,7 @@ static char *vstrfmtmake (size_t *lenp, const char *fmt, va_list ap)
     char *p;
     int n;
 
+    if (!fmt) fmt = "";
     p = xalloc(size);
     while (1) {
         n = vsnprintf (p, size, fmt, ap);