ext/soap: Fix SOAP xsd:hexBinary odd-length decoding

NEWS

@@ -78,6 +78,8 @@ PHP                                                                        NEWS
 - SOAP:
   . Fixed bug GH-22585 (OOM on bailout with uninitialized
     do_request() parameters). (David Carlier)
+  . Fixed xsd:hexBinary decoding to reject odd-length values instead of
+    silently truncating the last nibble. (Weilin Du)
 
 - Standard:
   . Fixed sleep() and usleep() to reject values that overflow the underlying

ext/soap/php_encoding.c

@@ -766,6 +766,7 @@ static zval *to_zval_base64(zval *ret, encodeTypePtr type, xmlNodePtr data)
 static zval *to_zval_hexbin(zval *ret, encodeTypePtr type, xmlNodePtr data)
 {
 	zend_string *str;
+	size_t content_len;
 	size_t i, j;
 	unsigned char c;
 
@@ -778,7 +779,12 @@ static zval *to_zval_hexbin(zval *ret, encodeTypePtr type, xmlNodePtr data)
 			soap_error0(E_ERROR, "Encoding: Violation of encoding rules");
 			return ret;
 		}
-		str = zend_string_alloc(strlen((char*)data->children->content) / 2, 0);
+		content_len = strlen((char*) data->children->content);
+		if (content_len % 2 != 0) {
+			soap_error0(E_ERROR, "Encoding: Violation of encoding rules");
+			return ret;
+		}
+		str = zend_string_alloc(content_len / 2, 0);
 		for (i = j = 0; i < ZSTR_LEN(str); i++) {
 			c = data->children->content[j++];
 			if (c >= '0' && c <= '9') {

ext/soap/tests/hexbin_odd_length.phpt

@@ -0,0 +1,37 @@
+--TEST--
+SOAP rejects odd-length xsd:hexBinary values
+--EXTENSIONS--
+soap
+--FILE--
+<?php
+class TestSoapClient extends SoapClient {
+    public function __doRequest($request, $location, $action, $version, $one_way = false, ?string $uriParserClass = null): string {
+        return <<<'XML'
+<?xml version="1.0" encoding="UTF-8"?>
+<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
+                   xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <SOAP-ENV:Body>
+    <ns1:testResponse xmlns:ns1="urn:test">
+      <return xsi:type="xsd:hexBinary">ABC</return>
+    </ns1:testResponse>
+  </SOAP-ENV:Body>
+</SOAP-ENV:Envelope>
+XML;
+    }
+}
+
+$client = new TestSoapClient(null, [
+    'location' => 'test://',
+    'uri' => 'urn:test',
+    'exceptions' => true,
+]);
+
+try {
+    var_dump(bin2hex($client->test()));
+} catch (SoapFault $e) {
+    echo $e->faultstring, "\n";
+}
+?>
+--EXPECT--
+SOAP-ERROR: Encoding: Violation of encoding rules