File u_xkb-Check-for-tbGetBuffer-failure.patch of Package xorg-x11-server.5551

Patch-mainline: To be upstreamed
Author: Michal Srb <msrb@suse.com>
Subject: xkb: Check for tbGetBuffer failure.
References: bnc#1051150 CVE-2017-13723

The requested length can be longer than the length of the input string because
of escaping.
---
It can be triggered by a long string containing characters that need escaping.

 xkb/xkbtext.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/xkb/xkbtext.c b/xkb/xkbtext.c
index 6dd979409..d77f7c9ed 100644
--- a/xkb/xkbtext.c
+++ b/xkb/xkbtext.c
@@ -580,6 +580,11 @@ XkbStringText(char *str, unsigned format)
     if (ok)
         return str;
     buf = tbGetBuffer(len + 1);
+    if (!buf) {
+        buf = tbGetBuffer(2);
+        buf[0] = '\0';
+        return buf;
+    }
     for (in = str, out = buf; *in != '\0'; in++) {
         if (isprint(*in))
             *out++ = *in;
-- 
2.12.3