Fix segfaults in wlr_surface_is_*

types/wlr_wl_shell.c

@@ -13,7 +13,8 @@
 static const char *wlr_wl_shell_surface_role = "wl-shell-surface";
 
 bool wlr_surface_is_wl_shell_surface(struct wlr_surface *surface) {
-	return strcmp(surface->role, wlr_wl_shell_surface_role) == 0;
+	return surface->role != NULL &&
+		strcmp(surface->role, wlr_wl_shell_surface_role) == 0;
 }
 
 struct wlr_wl_surface *wlr_wl_shell_surface_from_wlr_surface(

types/wlr_xdg_shell.c

@@ -17,8 +17,9 @@ static const char *wlr_desktop_xdg_toplevel_role = "xdg_toplevel";
 static const char *wlr_desktop_xdg_popup_role = "xdg_popup";
 
 bool wlr_surface_is_xdg_surface(struct wlr_surface *surface) {
-	return strcmp(surface->role, wlr_desktop_xdg_toplevel_role) == 0 ||
-		strcmp(surface->role, wlr_desktop_xdg_popup_role) == 0;
+	return surface->role != NULL &&
+		(strcmp(surface->role, wlr_desktop_xdg_toplevel_role) == 0 ||
+		strcmp(surface->role, wlr_desktop_xdg_popup_role) == 0);
 }
 
 struct wlr_xdg_surface *wlr_xdg_surface_from_wlr_surface(

types/wlr_xdg_shell_v6.c

@@ -17,8 +17,9 @@ static const char *wlr_desktop_xdg_toplevel_role = "xdg_toplevel_v6";
 static const char *wlr_desktop_xdg_popup_role = "xdg_popup_v6";
 
 bool wlr_surface_is_xdg_surface_v6(struct wlr_surface *surface) {
-	return strcmp(surface->role, wlr_desktop_xdg_toplevel_role) == 0 ||
-		strcmp(surface->role, wlr_desktop_xdg_popup_role) == 0;
+	return surface->role != NULL &&
+		(strcmp(surface->role, wlr_desktop_xdg_toplevel_role) == 0 ||
+		strcmp(surface->role, wlr_desktop_xdg_popup_role) == 0);
 }
 
 struct wlr_xdg_surface_v6 *wlr_xdg_surface_v6_from_wlr_surface(

xwayland/xwm.c

@@ -80,7 +80,8 @@ const char *atom_map[ATOM_LAST] = {
 const char *wlr_xwayland_surface_role = "wlr_xwayland_surface";
 
 bool wlr_surface_is_xwayland_surface(struct wlr_surface *surface) {
-	return strcmp(surface->role, wlr_xwayland_surface_role) == 0;
+	return surface->role != NULL &&
+		strcmp(surface->role, wlr_xwayland_surface_role) == 0;
 }
 
 struct wlr_xwayland_surface *wlr_xwayland_surface_from_wlr_surface(