From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC647C433E9 for ; Mon, 22 Mar 2021 12:38:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A95236191C for ; Mon, 22 Mar 2021 12:38:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231378AbhCVMih (ORCPT ); Mon, 22 Mar 2021 08:38:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:56988 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231628AbhCVMeA (ORCPT ); Mon, 22 Mar 2021 08:34:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A35A061998; Mon, 22 Mar 2021 12:33:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1616416440; bh=ft9Lb4MR6Vk8OXPD4zVw5IuZdRbUn+8SmoXMMeTeq2s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gGs3WrlDtGeb0YmPbdm6l+UdK5/FUSeuH0XHZccM/9eN0ibu9RQRweIK7Xb9i0+RF EmcPLZKUmEYOKlkDoTNPJ6D0XCHDK7SyMeMtRf8cBb1VCjM7c0pmhtUOgYApxdjCf6 wha7Zseoj9mwubwGz5T54u+T7wmi2tSUdBSsbF98= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shawn Guo , Ard Biesheuvel Subject: [PATCH 5.11 106/120] efivars: respect EFI_UNSUPPORTED return from firmware Date: Mon, 22 Mar 2021 13:28:09 +0100 Message-Id: <20210322121933.205331003@linuxfoundation.org> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210322121929.669628946@linuxfoundation.org> References: <20210322121929.669628946@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shawn Guo commit 483028edacab374060d93955382b4865a9e07cba upstream. As per UEFI spec 2.8B section 8.2, EFI_UNSUPPORTED may be returned by EFI variable runtime services if no variable storage is supported by firmware. In this case, there is no point for kernel to continue efivars initialization. That said, efivar_init() should fail by returning an error code, so that efivarfs will not be mounted on /sys/firmware/efi/efivars at all. Otherwise, user space like efibootmgr will be confused by the EFIVARFS_MAGIC seen there, while EFI variable calls cannot be made successfully. Cc: # v5.10+ Signed-off-by: Shawn Guo Acked-by: Ard Biesheuvel Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/efi/vars.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -485,6 +485,10 @@ int efivar_init(int (*func)(efi_char16_t } break; + case EFI_UNSUPPORTED: + err = -EOPNOTSUPP; + status = EFI_NOT_FOUND; + break; case EFI_NOT_FOUND: break; default: