Merge branch 'PHP-7.3' into PHP-7.4

* PHP-7.3:
  Fix #78814: strip_tags allows / in tag name => whitelist bypass

Author: cmb69

NEWS

@@ -30,6 +30,8 @@ PHP                                                                        NEWS
   . Fixed bug #78840 (imploding $GLOBALS crashes). (cmb)
   . Fixed bug #78833 (Integer overflow in pack causes out-of-bound access).
     (cmb)
+  . Fixed bug #78814 (strip_tags allows / in tag name => whitelist bypass).
+    (cmb)
 
 28 Nov 2019, PHP 7.4.0
 

ext/standard/string.c

@@ -5118,7 +5118,7 @@ int php_tag_find(char *tag, size_t len, const char *set) {
 					if (state == 0) {
 						state=1;
 					}
-					if (c != '/') {
+					if (c != '/' || (*(t-1) != '<' && *(t+1) != '>')) {
 						*(n++) = c;
 					}
 				} else {

ext/standard/tests/strings/bug78814.phpt

@@ -0,0 +1,8 @@
+--TEST--
+Bug #78814 (strip_tags allows / in tag name => whitelist bypass)
+--FILE--
+<?php
+echo strip_tags("<s/trong>b</strong>", "<strong>");
+?>
+--EXPECT--
+b</strong>