From 3c576260f23b4bf9dc311a622f07be93d8a37250 Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Fri, 17 Apr 2026 10:12:42 +1000
Subject: [PATCH] os/access: fix off-by-one in hostname character validation
 range

In siHostnameCheckAddr(), the digit validation range was 0x30-0x3A, but
0x3A is the colon character (':'). The ASCII range for digits 0-9 is
0x30-0x39.

Colons in hostnames violate RFC 2396 section 3.2.2 and we're not parsing
the host:port notation here.

Assisted-by: Claude:claude-claude-opus-4-6
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2200>
---
 os/access.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/os/access.c b/os/access.c
index 1daa36162..616a84b94 100644
--- a/os/access.c
+++ b/os/access.c
@@ -1879,7 +1879,7 @@ siHostnameCheckAddr(const char *valueString, int length, void *typePriv)
                     dotAllowed = FALSE;
                 }
             }
-            else if (((c >= 0x30) && (c <= 0x3A)) /* 0-9 */ ||
+            else if (((c >= 0x30) && (c <= 0x39)) /* 0-9 */ ||
                      ((c >= 0x61) && (c <= 0x7A)) /* a-z */ ||
                      ((c >= 0x41) && (c <= 0x5A)) /* A-Z */ ) {
                 dotAllowed = TRUE;