efi_loader: check the status of disconnected drivers

efi_uninstall_protocol() calls efi_disconnect_all_drivers() but never
checks the return value.  Instead it tries to identify protocols that
are still open after closing the ones that were opened with
EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL, EFI_OPEN_PROTOCOL_GET_PROTOCOL
and EFI_OPEN_PROTOCOL_TEST_PROTOCOL.

Instead of doing that,  check the return value early and exit if
disconnecting the drivers failed.  Also reconnect all the drivers of
a handle if protocols are still found on the handle after disconnecting
controllers and closing the remaining protocols.

While at it fix a memory leak and properly free the opened protocol
information when closing a protocol.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 5e932ee..d294db9 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -1374,17 +1374,23 @@
 	if (r != EFI_SUCCESS)
 		goto out;
 	/* Disconnect controllers */
-	efi_disconnect_all_drivers(efiobj, protocol, NULL);
+	r = efi_disconnect_all_drivers(efiobj, protocol, NULL);
+	if (r != EFI_SUCCESS) {
+		r = EFI_ACCESS_DENIED;
+		goto out;
+	}
 	/* Close protocol */
 	list_for_each_entry_safe(item, pos, &handler->open_infos, link) {
 		if (item->info.attributes ==
 			EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL ||
 		    item->info.attributes == EFI_OPEN_PROTOCOL_GET_PROTOCOL ||
 		    item->info.attributes == EFI_OPEN_PROTOCOL_TEST_PROTOCOL)
-			list_del(&item->link);
+			efi_delete_open_info(item);
 	}
+	/* if agents didn't close the protocols properly */
 	if (!list_empty(&handler->open_infos)) {
 		r =  EFI_ACCESS_DENIED;
+		EFI_CALL(efi_connect_controller(handle, NULL, NULL, true));
 		goto out;
 	}
 	r = efi_remove_protocol(handle, protocol, protocol_interface);