Refrain from listener rebinding when address families differ

changes/bug27928

@@ -0,0 +1,4 @@
+  o Minor bugfixes (networking):
+    - Refrain from attempting socket rebinding when old
+      and new listeners are in different address families.
+      Fixes bug 27928; bugfix on 0.3.5.1-alpha.

src/core/mainloop/connection.c

@@ -2798,6 +2798,7 @@ retry_listener_ports(smartlist_t *old_conns,
         }
 #ifdef ENABLE_LISTENER_REBIND
         const int may_need_rebind =
+          tor_addr_family(&wanted->addr) == tor_addr_family(&conn->addr) &&
           port_matches_exact && bool_neq(tor_addr_is_null(&wanted->addr),
                                          tor_addr_is_null(&conn->addr));
         if (replacements && may_need_rebind) {