From patchwork Thu Apr 9 13:04:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206428 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 D90B4C38A24 for ; Thu, 9 Apr 2020 13:05:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B1001214DB for ; Thu, 9 Apr 2020 13:05:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586437519; bh=U7IetTerUYNpcR10zlJAkIrjjq2uos2SYYzL0HOR3ec=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RwT25FKLSssJsR/bYBYSSzbEIEF+4Rx5uP0yrydEB7GUk20HU7NNdrqyroP8YXmEs mKBZ7op6p7tDOSW0I9nNrbbNqxQ2wzVR8h8kW70/V6B2u6E36D7MNVFN2BX3v2VRaj Cpn4ZtvXSsVxWjXntYqRUdy5M5U7l0DxY7dOwGr0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726894AbgDINFP (ORCPT ); Thu, 9 Apr 2020 09:05:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:44108 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726890AbgDINFO (ORCPT ); Thu, 9 Apr 2020 09:05:14 -0400 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4A15B2145D; Thu, 9 Apr 2020 13:05:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586437514; bh=U7IetTerUYNpcR10zlJAkIrjjq2uos2SYYzL0HOR3ec=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xVivXXWyqayWq6D9G+GLJSsib5ank0YIP/DlXzSb3ojl9NUp29WtTFoTRjchC+1/w A28mpGBqaNA2Ho+J+3n77Wx/iwLrbFCH9nbhcihRObyk4M6yxnpXrPRX4CQSUuW4+l k3HlNVVBXb1Jhla4DRwvTMZyM51y1pURzKWFi2mc= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, Arnd Bergmann , Arvind Sankar , Borislav Petkov , Colin Ian King , Gary Lin , Jiri Slaby , Sergey Shatunov , Takashi Iwai Subject: [PATCH 7/9] efi/libstub/file: merge filename buffers to reduce stack usage Date: Thu, 9 Apr 2020 15:04:32 +0200 Message-Id: <20200409130434.6736-8-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200409130434.6736-1-ardb@kernel.org> References: <20200409130434.6736-1-ardb@kernel.org> Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Arnd reports that commit 9302c1bb8e47 ("efi/libstub: Rewrite file I/O routine") reworks the file I/O routines in a way that triggers the following warning: drivers/firmware/efi/libstub/file.c:240:1: warning: the frame size of 1200 bytes is larger than 1024 bytes [-Wframe-larger-than=] We can work around this issue dropping an instance of efi_char16_t[256] from the stack frame, and reusing the 'filename' field of the file info struct that we use to obtain file information from EFI (which contains the filename even though we already know it since we used it to open the file in the first place) Reported-by: Arnd Bergmann Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/file.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/drivers/firmware/efi/libstub/file.c b/drivers/firmware/efi/libstub/file.c index d4c7e5f59d2c..ea66b1f16a79 100644 --- a/drivers/firmware/efi/libstub/file.c +++ b/drivers/firmware/efi/libstub/file.c @@ -29,30 +29,31 @@ */ #define EFI_READ_CHUNK_SIZE SZ_1M +struct finfo { + efi_file_info_t info; + efi_char16_t filename[MAX_FILENAME_SIZE]; +}; + static efi_status_t efi_open_file(efi_file_protocol_t *volume, - efi_char16_t *filename_16, + struct finfo *fi, efi_file_protocol_t **handle, unsigned long *file_size) { - struct { - efi_file_info_t info; - efi_char16_t filename[MAX_FILENAME_SIZE]; - } finfo; efi_guid_t info_guid = EFI_FILE_INFO_ID; efi_file_protocol_t *fh; unsigned long info_sz; efi_status_t status; - status = volume->open(volume, &fh, filename_16, EFI_FILE_MODE_READ, 0); + status = volume->open(volume, &fh, fi->filename, EFI_FILE_MODE_READ, 0); if (status != EFI_SUCCESS) { pr_efi_err("Failed to open file: "); - efi_char16_printk(filename_16); + efi_char16_printk(fi->filename); efi_printk("\n"); return status; } - info_sz = sizeof(finfo); - status = fh->get_info(fh, &info_guid, &info_sz, &finfo); + info_sz = sizeof(struct finfo); + status = fh->get_info(fh, &info_guid, &info_sz, fi); if (status != EFI_SUCCESS) { pr_efi_err("Failed to get file info\n"); fh->close(fh); @@ -60,7 +61,7 @@ static efi_status_t efi_open_file(efi_file_protocol_t *volume, } *handle = fh; - *file_size = finfo.info.file_size; + *file_size = fi->info.file_size; return EFI_SUCCESS; } @@ -146,13 +147,13 @@ static efi_status_t handle_cmdline_files(efi_loaded_image_t *image, alloc_addr = alloc_size = 0; do { - efi_char16_t filename[MAX_FILENAME_SIZE]; + struct finfo fi; unsigned long size; void *addr; offset = find_file_option(cmdline, cmdline_len, optstr, optstr_size, - filename, ARRAY_SIZE(filename)); + fi.filename, ARRAY_SIZE(fi.filename)); if (!offset) break; @@ -166,7 +167,7 @@ static efi_status_t handle_cmdline_files(efi_loaded_image_t *image, return status; } - status = efi_open_file(volume, filename, &file, &size); + status = efi_open_file(volume, &fi, &file, &size); if (status != EFI_SUCCESS) goto err_close_volume;