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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 212A8C3A5A8 for ; Wed, 4 Sep 2019 18:24:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA4C820870 for ; Wed, 4 Sep 2019 18:24:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567621457; bh=OB04hPq4goy2WxzaUI+Dt3CGXgwKpr20c1CJuDud7zY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ihPTipdD4YL5dj9Tc9+ScCVvG1flpowy9JuzVbrtBUc5VSuWIYDPCix7i6Szq0dSJ MSsVki8CXfqfjr5n/AlRd8DtOG+Il/dkUGD9Anq6vC9h38ldH082gIul7MppndcvcH QLd9ACLZJtrcalZSLeF5RiHEXDpqJCndwfY8wCT4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387617AbfIDSBu (ORCPT ); Wed, 4 Sep 2019 14:01:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:41480 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729626AbfIDSBt (ORCPT ); Wed, 4 Sep 2019 14:01:49 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AC94022CF7; Wed, 4 Sep 2019 18:01:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620108; bh=OB04hPq4goy2WxzaUI+Dt3CGXgwKpr20c1CJuDud7zY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ryjHXyFt/w+9hWDeZ7z3Lpdk5duKx9ZHI+OLI7PJKIryvUJF3uUduE6/pG2Xhv68P QxQWgCXWS/DHFHpJULFWZy8Kel2sXWLu4pDE4iVegf3EVdRnSNLaSSNcIbVxI3bOXr FD0AM0DL+yIMfuyotFDFSVu+y8Py11JAhXaHXusU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Gleixner , "H. Peter Anvin" , John Hubbard Subject: [PATCH 4.9 35/83] x86/boot: Save fields explicitly, zero out everything else Date: Wed, 4 Sep 2019 19:53:27 +0200 Message-Id: <20190904175306.963508734@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904175303.488266791@linuxfoundation.org> References: <20190904175303.488266791@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: John Hubbard commit a90118c445cc7f07781de26a9684d4ec58bfcfd1 upstream. Recent gcc compilers (gcc 9.1) generate warnings about an out of bounds memset, if the memset goes accross several fields of a struct. This generated a couple of warnings on x86_64 builds in sanitize_boot_params(). Fix this by explicitly saving the fields in struct boot_params that are intended to be preserved, and zeroing all the rest. [ tglx: Tagged for stable as it breaks the warning free build there as well ] Suggested-by: Thomas Gleixner Suggested-by: H. Peter Anvin Signed-off-by: John Hubbard Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190731054627.5627-2-jhubbard@nvidia.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/bootparam_utils.h | 59 +++++++++++++++++++++++++-------- 1 file changed, 46 insertions(+), 13 deletions(-) --- a/arch/x86/include/asm/bootparam_utils.h +++ b/arch/x86/include/asm/bootparam_utils.h @@ -17,6 +17,20 @@ * Note: efi_info is commonly left uninitialized, but that field has a * private magic, so it is better to leave it unchanged. */ + +#define sizeof_mbr(type, member) ({ sizeof(((type *)0)->member); }) + +#define BOOT_PARAM_PRESERVE(struct_member) \ + { \ + .start = offsetof(struct boot_params, struct_member), \ + .len = sizeof_mbr(struct boot_params, struct_member), \ + } + +struct boot_params_to_save { + unsigned int start; + unsigned int len; +}; + static void sanitize_boot_params(struct boot_params *boot_params) { /* @@ -35,19 +49,38 @@ static void sanitize_boot_params(struct */ if (boot_params->sentinel) { /* fields in boot_params are left uninitialized, clear them */ - memset(&boot_params->ext_ramdisk_image, 0, - (char *)&boot_params->efi_info - - (char *)&boot_params->ext_ramdisk_image); - memset(&boot_params->kbd_status, 0, - (char *)&boot_params->hdr - - (char *)&boot_params->kbd_status); - memset(&boot_params->_pad7[0], 0, - (char *)&boot_params->edd_mbr_sig_buffer[0] - - (char *)&boot_params->_pad7[0]); - memset(&boot_params->_pad8[0], 0, - (char *)&boot_params->eddbuf[0] - - (char *)&boot_params->_pad8[0]); - memset(&boot_params->_pad9[0], 0, sizeof(boot_params->_pad9)); + static struct boot_params scratch; + char *bp_base = (char *)boot_params; + char *save_base = (char *)&scratch; + int i; + + const struct boot_params_to_save to_save[] = { + BOOT_PARAM_PRESERVE(screen_info), + BOOT_PARAM_PRESERVE(apm_bios_info), + BOOT_PARAM_PRESERVE(tboot_addr), + BOOT_PARAM_PRESERVE(ist_info), + BOOT_PARAM_PRESERVE(hd0_info), + BOOT_PARAM_PRESERVE(hd1_info), + BOOT_PARAM_PRESERVE(sys_desc_table), + BOOT_PARAM_PRESERVE(olpc_ofw_header), + BOOT_PARAM_PRESERVE(efi_info), + BOOT_PARAM_PRESERVE(alt_mem_k), + BOOT_PARAM_PRESERVE(scratch), + BOOT_PARAM_PRESERVE(e820_entries), + BOOT_PARAM_PRESERVE(eddbuf_entries), + BOOT_PARAM_PRESERVE(edd_mbr_sig_buf_entries), + BOOT_PARAM_PRESERVE(edd_mbr_sig_buffer), + BOOT_PARAM_PRESERVE(eddbuf), + }; + + memset(&scratch, 0, sizeof(scratch)); + + for (i = 0; i < ARRAY_SIZE(to_save); i++) { + memcpy(save_base + to_save[i].start, + bp_base + to_save[i].start, to_save[i].len); + } + + memcpy(boot_params, save_base, sizeof(*boot_params)); } }