Fix out of bound writes to SafeArray data

Converting PHP arrays to Variants originally supported almost arbitrary
numeric arrays, possibly filling gaps with NULL values.  This is broken
as of PHP 7.0.0[1] so that the SafeArray only has as many elements as
the PHP array.  Thus, unless the array is a list, some elements may be
written outside of the SafeArray data.

To avoid breaking userland code after that long time, we do not restore
the original behavior, but instead only suppress the erroneous writes.

To avoid the need to split the regression test for 32bit and 64bit
Windows, we suppress the "max number 4294967295 of elements in safe
array exceeded" warning, which only occurs for 64bit versions.

[1] <c865472ef0>

Closes GH-16309.

NEWS

@@ -2,6 +2,9 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.2.26
 
+- COM:
+  . Fixed out of bound writes to SafeArray data. (cmb)
+
 - Curl:
   . Fixed bug GH-16302 (CurlMultiHandle holds a reference to CurlHandle if
     curl_multi_add_handle fails). (timwolla)

ext/com_dotnet/com_variant.c

@@ -26,8 +26,7 @@
 
 /* create an automation SafeArray from a PHP array.
  * Only creates a single-dimensional array of variants.
- * The keys of the PHP hash MUST be numeric.  If the array
- * is sparse, then the gaps will be filled with NULL variants */
+ * The keys of the PHP hash MUST be numeric. */
 static void safe_array_from_zval(VARIANT *v, zval *z, int codepage)
 {
 	SAFEARRAY *sa = NULL;
@@ -71,8 +70,10 @@ static void safe_array_from_zval(VARIANT *v, zval *z, int codepage)
 			break;
 		}
 		zend_hash_get_current_key_ex(Z_ARRVAL_P(z), &strindex, &intindex, &pos);
+		if (intindex < bound.cElements) {
 			php_com_variant_from_zval(&va[intindex], item, codepage);
 		}
+	}
 
 	/* Unlock it and stuff it into our variant */
 	SafeArrayUnaccessData(sa);

ext/com_dotnet/tests/variant_variation.phpt

@@ -0,0 +1,30 @@
+--TEST--
+Testing variant arrays
+--EXTENSIONS--
+com_dotnet
+--FILE--
+<?php
+$arrays = [
+    "order" => [2 => 1, 1 => 2, 0 => 3],
+    "off" => [2 => 1, 1 => 2, 3],
+    "negative" => [-1 => 42],
+];
+foreach ($arrays as $desc => $array) {
+    echo "-- $desc --\n";
+    $v = new variant($array);
+    foreach ($v as $val) {
+        var_dump($val);
+    }
+}
+?>
+--EXPECTF--
+-- order --
+int(3)
+int(2)
+int(1)
+-- off --
+NULL
+int(2)
+int(1)
+-- negative --
+%ANULL