validate grab serial for shell events

include/wlr/types/wlr_seat.h

@@ -509,4 +509,10 @@ int wlr_seat_touch_num_points(struct wlr_seat *seat);
  */
 bool wlr_seat_touch_has_grab(struct wlr_seat *seat);
 
+/**
+ * Check whether this serial is valid to start a grab action such as an
+ * interactive move or resize.
+ */
+bool wlr_seat_validate_grab_serial(struct wlr_seat *seat, uint32_t serial);
+
 #endif

rootston/wl_shell.c

@@ -43,7 +43,6 @@ static void handle_request_resize(struct wl_listener *listener, void *data) {
 	struct roots_input *input = view->desktop->server->input;
 	struct wlr_wl_shell_surface_resize_event *e = data;
 	struct roots_seat *seat = input_seat_from_wlr_seat(input, e->seat->seat);
-	// TODO verify input event
 	if (!seat || seat->cursor->mode != ROOTS_CURSOR_PASSTHROUGH) {
 		return;
 	}

types/wlr_seat.c

@@ -1216,3 +1216,8 @@ int wlr_seat_touch_num_points(struct wlr_seat *seat) {
 bool wlr_seat_touch_has_grab(struct wlr_seat *seat) {
 	return seat->touch_state.grab->interface != &default_touch_grab_impl;
 }
+
+bool wlr_seat_validate_grab_serial(struct wlr_seat *seat, uint32_t serial) {
+	return serial == seat->pointer_state.grab_serial ||
+		serial == seat->touch_state.grab_serial;
+}

types/wlr_wl_shell.c

@@ -112,6 +112,11 @@ static void shell_surface_protocol_move(struct wl_client *client,
 	struct wlr_seat_client *seat =
 		wl_resource_get_user_data(seat_resource);
 
+	if (!wlr_seat_validate_grab_serial(seat->seat, serial)) {
+		wlr_log(L_DEBUG, "invalid serial for grab");
+		return;
+	}
+
 	struct wlr_wl_shell_surface_move_event event = {
 		.surface = surface,
 		.seat = seat,
@@ -170,6 +175,11 @@ static void shell_surface_protocol_resize(struct wl_client *client,
 	struct wlr_seat_client *seat =
 		wl_resource_get_user_data(seat_resource);
 
+	if (!wlr_seat_validate_grab_serial(seat->seat, serial)) {
+		wlr_log(L_DEBUG, "invalid serial for grab");
+		return;
+	}
+
 	struct wlr_wl_shell_surface_resize_event event = {
 		.surface = surface,
 		.seat = seat,

types/wlr_xdg_shell_v6.c

@@ -565,6 +565,11 @@ static void xdg_toplevel_protocol_show_window_menu(struct wl_client *client,
 		return;
 	}
 
+	if (!wlr_seat_validate_grab_serial(seat->seat, serial)) {
+		wlr_log(L_DEBUG, "invalid serial for grab");
+		return;
+	}
+
 	struct wlr_xdg_toplevel_v6_show_window_menu_event event = {
 		.surface = surface,
 		.seat = seat,
@@ -590,6 +595,11 @@ static void xdg_toplevel_protocol_move(struct wl_client *client,
 		return;
 	}
 
+	if (!wlr_seat_validate_grab_serial(seat->seat, serial)) {
+		wlr_log(L_DEBUG, "invalid serial for grab");
+		return;
+	}
+
 	struct wlr_xdg_toplevel_v6_move_event event = {
 		.surface = surface,
 		.seat = seat,
@@ -613,6 +623,11 @@ static void xdg_toplevel_protocol_resize(struct wl_client *client,
 		return;
 	}
 
+	if (!wlr_seat_validate_grab_serial(seat->seat, serial)) {
+		wlr_log(L_DEBUG, "invalid serial for grab");
+		return;
+	}
+
 	struct wlr_xdg_toplevel_v6_resize_event event = {
 		.surface = surface,
 		.seat = seat,