From e7577d57cdae2e702961455bbe25ff02452f2ea0 Mon Sep 17 00:00:00 2001
From: Scott MacVicar <scottmac@php.net>
Date: Thu, 10 May 2007 13:16:54 +0000
Subject: [PATCH] Fixed bug #41347 (checkdnsrr() segfaults on empty hostname).

---
 NEWS                                     |  1 +
 ext/standard/dns.c                       | 12 ++++++++++++
 ext/standard/tests/network/bug41347.phpt | 19 +++++++++++++++++++
 3 files changed, 32 insertions(+)
 create mode 100644 ext/standard/tests/network/bug41347.phpt

diff --git a/NEWS b/NEWS
index 5801c863f50..5d9b9b169a2 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ PHP                                                                        NEWS
   (Ilia)
 - Fixed altering $this via argument named "this". (Dmitry)
 - Fixed PHP CLI to use the php.ini from the binary location. (Hannes)
+- Fixed bug #41347 (checkdnsrr() segfaults on empty hostname). (Scott)
 - Fixed bug #41326 (Writing empty tags with Xmlwriter::WriteElement[ns])
   (Pierre)
 - Fixed bug #41321 (downgrade read errors in getimagesize() to E_NOTICE).
diff --git a/ext/standard/dns.c b/ext/standard/dns.c
index fd408061678..4e4242458b4 100644
--- a/ext/standard/dns.c
+++ b/ext/standard/dns.c
@@ -264,6 +264,12 @@ PHP_FUNCTION(dns_check_record)
 			}
 			type = T_MX;
 			convert_to_string_ex(arg1);
+			
+			if (Z_STRLEN_PP(arg1) == 0)
+			{
+				php_error_docref(NULL TSRMLS_CC, E_WARNING, "Host cannot be empty");
+				RETURN_FALSE;
+			}
 			break;
 
 		case 2:
@@ -273,6 +279,12 @@ PHP_FUNCTION(dns_check_record)
 			convert_to_string_ex(arg1);
 			convert_to_string_ex(arg2);
 
+			if (Z_STRLEN_PP(arg1) == 0 || Z_STRLEN_PP(arg2) == 0)
+			{
+				php_error_docref(NULL TSRMLS_CC, E_WARNING, "Host and type cannot be empty");
+				RETURN_FALSE;
+			}
+
 			if (!strcasecmp("A", Z_STRVAL_PP(arg2))) type = T_A;
 			else if (!strcasecmp("NS",    Z_STRVAL_PP(arg2))) type = DNS_T_NS;
 			else if (!strcasecmp("MX",    Z_STRVAL_PP(arg2))) type = DNS_T_MX;
diff --git a/ext/standard/tests/network/bug41347.phpt b/ext/standard/tests/network/bug41347.phpt
new file mode 100644
index 00000000000..ef93a202bc5
--- /dev/null
+++ b/ext/standard/tests/network/bug41347.phpt
@@ -0,0 +1,19 @@
+--TEST--
+dns_check_record() segfault with empty host
+--SKIPIF--
+<?php
+if (substr(PHP_OS, 0, 3) == 'WIN') {
+    die('No windows support');
+}
+?>
+--FILE--
+<?php
+var_dump(dns_check_record(''));
+var_dump(dns_check_record('', ''));
+?>
+--EXPECTF--
+Warning: dns_check_record(): Host cannot be empty in %s on line %d
+bool(false)
+
+Warning: dns_check_record(): Host and type cannot be empty in %s on line %d
+bool(false)