diff --git a/tools/libinput-debug-tablet.c b/tools/libinput-debug-tablet.c
index 2848dc64..5e074261 100644
--- a/tools/libinput-debug-tablet.c
+++ b/tools/libinput-debug-tablet.c
@@ -277,8 +277,12 @@ handle_device_added(struct context *ctx, struct libinput_event *ev)
 	devnode = udev_device_get_devnode(udev_device);
 	if (devnode) {
 		int fd = open(devnode, O_RDONLY | O_NONBLOCK | O_CLOEXEC);
-		assert(fd != -1);
-		assert(libevdev_new_from_fd(fd, &ctx->evdev) == 0);
+		if (fd == -1)
+			return;
+		if (libevdev_new_from_fd(fd, &ctx->evdev) != 0) {
+			close(fd);
+			return;
+		}
 		ctx->fds[1].fd = fd;
 	}