Validate pattern against mbregex encoding

Oniguruma does not consistently perform this validation itself (at least
on older versions), so make sure we check pattern encoding validity on the
PHP side.

Author: nikic

ext/mbstring/php_mbregex.c

@@ -451,13 +451,18 @@ static php_mb_regex_t *php_mbregex_compile_pattern(const char *pattern, int patl
 	OnigErrorInfo err_info;
 	OnigUChar err_str[ONIG_MAX_ERROR_MESSAGE_LEN];
 
+	if (!php_mb_check_encoding(pattern, patlen, _php_mb_regex_mbctype2name(enc))) {
+		php_error_docref(NULL, E_WARNING,
+			"Pattern is not valid under %s encoding", _php_mb_regex_mbctype2name(enc));
+		return NULL;
+	}
+
 	rc = zend_hash_str_find_ptr(&MBREX(ht_rc), (char *)pattern, patlen);
 	if (!rc || onig_get_options(rc) != options || onig_get_encoding(rc) != enc || onig_get_syntax(rc) != syntax) {
 		if ((err_code = onig_new(&retval, (OnigUChar *)pattern, (OnigUChar *)(pattern + patlen), options, enc, syntax, &err_info)) != ONIG_NORMAL) {
 			onig_error_code_to_str(err_str, err_code, &err_info);
 			php_error_docref(NULL, E_WARNING, "mbregex compile err: %s", err_str);
-			retval = NULL;
-			goto out;
+			return NULL;
 		}
 		if (rc == MBREX(search_re)) {
 			/* reuse the new rc? see bug #72399 */
@@ -467,7 +472,6 @@ static php_mb_regex_t *php_mbregex_compile_pattern(const char *pattern, int patl
 	} else {
 		retval = rc;
 	}
-out:
 	return retval;
 }
 /* }}} */

ext/mbstring/tests/bug72994.phpt

@@ -13,5 +13,7 @@ var_dump($var1);
 ===DONE===
 --EXPECTF--
 Notice: Undefined variable: var in %s on line %d
-string(0) ""
+
+Warning: mbereg_replace(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)
 ===DONE===

ext/mbstring/tests/bug77370.phpt

@@ -6,8 +6,6 @@ Bug #77370 (Buffer overflow on mb regex functions - fetch_token)
 <?php
 var_dump(mb_split("   \xfd",""));
 ?>
---EXPECT--
-array(1) {
-  [0]=>
-  string(0) ""
-}
+--EXPECTF--
+Warning: mb_split(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)

ext/mbstring/tests/bug77371.phpt

@@ -6,5 +6,6 @@ Bug #77371 (heap buffer overflow in mb regex functions - compile_string_node)
 <?php
 var_dump(mb_ereg("()0\xfc00000\xfc00000\xfc00000\xfc",""));
 ?>
---EXPECT--
-bool(false)
+--EXPECTF--
+Warning: mb_ereg(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)

ext/mbstring/tests/bug77381.phpt

@@ -9,8 +9,15 @@ var_dump(mb_ereg("(?i)000000000000000000000\xf0",""));
 var_dump(mb_ereg("0000\\"."\xf5","0"));
 var_dump(mb_ereg("(?i)FFF00000000000000000\xfd",""));
 ?>
---EXPECT--
-int(1)
+--EXPECTF--
+Warning: mb_ereg(): Pattern is not valid under UTF-8 encoding in %s on line %d
 bool(false)
+
+Warning: mb_ereg(): Pattern is not valid under UTF-8 encoding in %s on line %d
 bool(false)
+
+Warning: mb_ereg(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)
+
+Warning: mb_ereg(): Pattern is not valid under UTF-8 encoding in %s on line %d
 bool(false)

ext/mbstring/tests/mb_ereg_replace_variation1.phpt

@@ -109,13 +109,17 @@ string(10) "string_val"
 string(10) "string_val"
 
 -- Iteration 4 --
-string(10) "string_val"
+
+Warning: mb_ereg_replace(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)
 
 -- Iteration 5 --
 string(10) "string_val"
 
 -- Iteration 6 --
-string(10) "string_val"
+
+Warning: mb_ereg_replace(): Pattern is not valid under UTF-8 encoding in %s on line %d
+bool(false)
 
 -- Iteration 7 --
 string(10) "string_val"