From patchwork Mon Jul 26 14:51:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 486030 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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 F2EAFC41537 for ; Mon, 26 Jul 2021 14:52:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFACA60F59 for ; Mon, 26 Jul 2021 14:52:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234606AbhGZOLo (ORCPT ); Mon, 26 Jul 2021 10:11:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:53118 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234679AbhGZOLj (ORCPT ); Mon, 26 Jul 2021 10:11:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D4A8060F55; Mon, 26 Jul 2021 14:52:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627311128; bh=FL4XscM/XE1HlSxzzIgal5E9ANumuP+Cm/xIkiJYOxg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MtiPxwUzhbv1NycIDYzPr/+wphukJlZG1AllhC03Y+kim9P5uVjKZS6EuiX6eBAir JJipAXDq/lcGVSbubMsqCQvZyXj0hMYl83O0jrOhbI0VoWwtoMXhdMV5VjvppBQqlG c1kLrcgwDoxR38YEnQHSEnSvgqIcXEbCvNTIA734Ce61rZgloe93ONK4xnDgrOVIVg GibqZlTfGdRLPGbdQR9B2JROk2BxwmJ8wdMi7Bu3WmdoFYUv7UuIvRjj6bgCTdWj63 xG2/kK2mu0KfQuCHQRIJITSTTmA2FexD9KwRXeo5TFZlIU8xg9/Z00ELLQtyuWF1vL 51lZvu79s1/iQ== From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Ard Biesheuvel Subject: [PATCH v3 3/4] efi/libstub: arm64: Warn when efi_random_alloc() fails Date: Mon, 26 Jul 2021 16:51:55 +0200 Message-Id: <20210726145156.12006-4-ardb@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210726145156.12006-1-ardb@kernel.org> References: <20210726145156.12006-1-ardb@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Randomization of the physical load address of the kernel image relies on efi_random_alloc() returning successfully, and currently, we ignore any failures and just carry on, using the ordinary, non-randomized page allocator routine. This means we never find out if a failure occurs, which could harm security, so let's at least warn about this condition. Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/arm64-stub.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 6f214c9c303e..010564f8bbc4 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -130,6 +130,8 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, */ status = efi_random_alloc(*reserve_size, min_kimg_align, reserve_addr, phys_seed); + if (status != EFI_SUCCESS) + efi_warn("efi_random_alloc() failed: 0x%lx\n", status); } else { status = EFI_OUT_OF_RESOURCES; }