From patchwork Fri Mar 10 08:45:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 661899 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9AAAC6FD1E for ; Fri, 10 Mar 2023 08:48:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231394AbjCJIsW (ORCPT ); Fri, 10 Mar 2023 03:48:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231315AbjCJIrl (ORCPT ); Fri, 10 Mar 2023 03:47:41 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62F3B3CE24 for ; Fri, 10 Mar 2023 00:45:47 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 16751B821F2 for ; Fri, 10 Mar 2023 08:45:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C672BC4339E; Fri, 10 Mar 2023 08:45:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678437944; bh=kOTi1Srm5yOU6EhaUForql09xCQCj7l7d9TwDjow/4o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TIYiSTcaX//AKw+YwwVigxd/dY0UaY2Pj6YCbjvn59MuFz5EvDf/X2jSRkYq4gzxU /wO+0l8hLXO/+/CxcldV7Coz/SD1f2dvPAgR10gs2ODpNu3voIzP+g+U8MeENi3NRJ LzoIi5xOZgw0qKinxlun1DGr1I9LEnBOT5NnFYRW5EAk1MQoZd9C6ZISQYv0w6FTac Cyzdbyqp3RO11DB8a7GWj+GECOkEM7zaYSO9DOw77vFfDkAnMgLQXx5gVGlLgJmHlB TnlEqVPNubMkid7U+zdGDoHluiOZTJN8g5N+hr0wuEyGMWu8xK6oD0Mws5wMDVLsqt 60eufSCEthWsA== From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: Ard Biesheuvel , Michael Brown , Ilias Apalodimas Subject: [PATCH 2/2] efi: libstub: Look for initrd LoadFile2 protocol on image handle Date: Fri, 10 Mar 2023 09:45:29 +0100 Message-Id: <20230310084529.3229983-3-ardb@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310084529.3229983-1-ardb@kernel.org> References: <20230310084529.3229983-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=6052; i=ardb@kernel.org; h=from:subject; bh=kOTi1Srm5yOU6EhaUForql09xCQCj7l7d9TwDjow/4o=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIYXrnSYXY5doj9/sbedVr6pdFkjZMCe55sqcla2Om1947 3aZUxXWUcrCIMbBICumyCIw+++7nacnStU6z5KFmcPKBDKEgYtTACbyfS3DH77YJ7G3NT6UXliy mcNGfUPgrladvxY3r9+M+NX78tqMBVcYGZ6o2E+rbs7onrno1IpJ8x8LWTgxX3vtkHJz506vzxP s9XkB X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org The use of a global singleton device path for describing the initrd to be loaded by the kernel implies that only a single handle can exist that carries the initrd LoadFile2 protocol implementation. This avoids the need on the part of the EFI stub to reason about which initrd is the preferred one when several are being provided - we already have initrd loading via the setup header on x86 and via DT on other architectures, in addition to the initrd= command line option, and so having a single loader provided initrd that supersedes all of them was deemed preferable over having multiple sources. However, this means that intermediate loader stages cannot simply install the LoadFile2 initrd device path, and will need to check for failures and deal with them. It also means that such stages will have to reason about whether or not the subsequent stage being loaded is the final one, or whether it may attempt to install the initrd device path itself. We can solve this by associating the initrd LoadFile2 protocol with the loaded image instead of with a global singleton device path. That way, each stage can associate any initrd it provides with the image that it is loading. Signed-off-by: Ard Biesheuvel Tested-by: Ilias Apalodimas Reviewed-by: Ilias Apalodimas --- drivers/firmware/efi/libstub/efi-stub-helper.c | 42 ++++++++++++-------- include/linux/efi.h | 2 +- include/linux/pe.h | 2 +- 3 files changed, 28 insertions(+), 18 deletions(-) diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index d47aa855398b39a6..a97c95a1d99e0b9d 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -482,10 +482,11 @@ static const struct { }; /** - * efi_load_initrd_dev_path() - load the initrd from the Linux initrd device path - * @initrd: pointer of struct to store the address where the initrd was loaded - * and the size of the loaded initrd - * @max: upper limit for the initrd memory allocation + * efi_load_initrd_lf2() - load the initrd from the Linux initrd device path + * @image_handle: EFI handle of the loaded image + * @initrd: pointer of struct to store the address where the initrd was + * loaded and the size of the loaded initrd + * @max: upper limit for the initrd memory allocation * * Return: * * %EFI_SUCCESS if the initrd was loaded successfully, in which @@ -495,24 +496,33 @@ static const struct { * * %EFI_LOAD_ERROR in all other cases */ static -efi_status_t efi_load_initrd_dev_path(struct linux_efi_initrd *initrd, - unsigned long max) +efi_status_t efi_load_initrd_lf2(efi_handle_t image_handle, + struct linux_efi_initrd *initrd, + unsigned long max) { efi_guid_t lf2_proto_guid = EFI_LOAD_FILE2_PROTOCOL_GUID; + efi_guid_t initrd_lf2_proto_guid = LINUX_EFI_INITRD_LF2_PROTOCOL_GUID; efi_device_path_protocol_t *dp; efi_load_file2_protocol_t *lf2; efi_handle_t handle; efi_status_t status; - dp = (efi_device_path_protocol_t *)&initrd_dev_path; - status = efi_bs_call(locate_device_path, &lf2_proto_guid, &dp, &handle); - if (status != EFI_SUCCESS) - return status; - - status = efi_bs_call(handle_protocol, handle, &lf2_proto_guid, + /* first look for a initrd loading protocol specific to this image */ + status = efi_bs_call(handle_protocol, image_handle, &initrd_lf2_proto_guid, (void **)&lf2); - if (status != EFI_SUCCESS) - return status; + if (status != EFI_SUCCESS) { + /* look for the global singleton initrd loading protocol */ + dp = (efi_device_path_protocol_t *)&initrd_dev_path; + status = efi_bs_call(locate_device_path, &lf2_proto_guid, &dp, + &handle); + if (status != EFI_SUCCESS) + return status; + + status = efi_bs_call(handle_protocol, handle, &lf2_proto_guid, + (void **)&lf2); + if (status != EFI_SUCCESS) + return status; + } initrd->size = 0; status = efi_call_proto(lf2, load_file, dp, false, &initrd->size, NULL); @@ -567,9 +577,9 @@ efi_status_t efi_load_initrd(efi_handle_t handle, if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD) || efi_noinitrd) return EFI_SUCCESS; - status = efi_load_initrd_dev_path(&initrd, hard_limit); + status = efi_load_initrd_lf2(handle, &initrd, hard_limit); if (status == EFI_SUCCESS) { - efi_info("Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path\n"); + efi_info("Loaded initrd using LoadFile2 protocol\n"); if (initrd.size > 0 && efi_measure_tagged_event(initrd.base, initrd.size, EFISTUB_EVT_INITRD) == EFI_SUCCESS) diff --git a/include/linux/efi.h b/include/linux/efi.h index 04a733f0ba956211..83643d6aee755d85 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -417,7 +417,7 @@ void efi_native_runtime_setup(void); #define LINUX_EFI_MOK_VARIABLE_TABLE_GUID EFI_GUID(0xc451ed2b, 0x9694, 0x45d3, 0xba, 0xba, 0xed, 0x9f, 0x89, 0x88, 0xa3, 0x89) #define LINUX_EFI_COCO_SECRET_AREA_GUID EFI_GUID(0xadf956ad, 0xe98c, 0x484c, 0xae, 0x11, 0xb5, 0x1c, 0x7d, 0x33, 0x64, 0x47) #define LINUX_EFI_BOOT_MEMMAP_GUID EFI_GUID(0x800f683f, 0xd08b, 0x423a, 0xa2, 0x93, 0x96, 0x5c, 0x3c, 0x6f, 0xe2, 0xb4) - +#define LINUX_EFI_INITRD_LF2_PROTOCOL_GUID EFI_GUID(0xf9e3378e, 0xb3b1, 0x423a, 0xbd, 0x9a, 0x2d, 0x08, 0x60, 0x28, 0x7f, 0x72) #define RISCV_EFI_BOOT_PROTOCOL_GUID EFI_GUID(0xccd15fec, 0x6f73, 0x4eec, 0x83, 0x95, 0x3e, 0x69, 0xe4, 0xb9, 0x40, 0xbf) /* diff --git a/include/linux/pe.h b/include/linux/pe.h index 6ffabf1e6d039e67..934e3a15ea7ddc07 100644 --- a/include/linux/pe.h +++ b/include/linux/pe.h @@ -29,7 +29,7 @@ * handover_offset and xloadflags fields in the bootparams structure. */ #define LINUX_EFISTUB_MAJOR_VERSION 0x1 -#define LINUX_EFISTUB_MINOR_VERSION 0x1 +#define LINUX_EFISTUB_MINOR_VERSION 0x2 /* * LINUX_PE_MAGIC appears at offset 0x38 into the MS-DOS header of EFI bootable