Do not treat display names as globs for push rules.

changelog.d/7271.bugfix

@@ -0,0 +1 @@
+Do not treat display names as globs in push rules.

synapse/push/push_rule_evaluator.py

@@ -142,13 +142,21 @@ def _contains_display_name(self, display_name):
         if not body:
             return False
 
-        return _glob_matches(display_name, body, word_boundary=True)
+        # Similar to _glob_matches, but do not treat display_name as a glob.
+        r = regex_cache.get((display_name, False, True), None)
+        if not r:
+            r = re.escape(display_name)
+            r = _re_word_boundary(r)
+            r = re.compile(r, flags=re.IGNORECASE)
+            regex_cache[(display_name, False, True)] = r
+
+        return r.search(body)
 
     def _get_value(self, dotted_key):
         return self._value_cache.get(dotted_key, None)
 
 
-# Caches (glob, word_boundary) -> regex for push. See _glob_matches
+# Caches (string, is_glob, word_boundary) -> regex for push. See _glob_matches
 regex_cache = LruCache(50000 * CACHE_SIZE_FACTOR)
 register_cache("cache", "regex_push_cache", regex_cache)
 
@@ -167,10 +175,10 @@ def _glob_matches(glob, value, word_boundary=False):
     """
 
     try:
-        r = regex_cache.get((glob, word_boundary), None)
+        r = regex_cache.get((glob, True, word_boundary), None)
         if not r:
             r = _glob_to_re(glob, word_boundary)
-            regex_cache[(glob, word_boundary)] = r
+            regex_cache[(glob, True, word_boundary)] = r
         return r.search(value)
     except re.error:
         logger.warning("Failed to parse glob to regex: %r", glob)